Fish Culture in Undrainable Ponds

1.INTRODUCTION Fish culture is the rational cultivation of fish in a confined water area where the practices of both agriculture and animal husbandry are applicable. The soil and water management aspect of fish culture practice involving application of organic manures and inorganic fertilizers for the production of microscopic plants, the phytoplankton, is basically similar to agriculture while husbandry of fish such as feeding, breeding and health care is more or less similar to a livestock farming system. This farming system is also unique in that the farmed animal is cold-blooded or poikilothermic and lives in a water medium. Although this fish farming is appro imately ! """ years old, the importance of it has been realized only recently in the face of mounting pressure on land resources and scarcity of animal protein for the ever increasing human population. #hile introducing fish culture, it seems reasonable to discuss certain important aspects of fish farming systems and their relevance to the rural development programme of developing countries. 1.1 Fish as Food $alnutrition and starvation are the two serious problems being faced by millions of rural poor in most of the developing countries. The problem of malnutrition is in fact more serious and of a bigger dimension than the starvation problem and is caused mainly due to animal protein-deficient diets. Animal protein is essential for proper growth, repair and maintenance of body organs and tissues. Fish contain about %&'!"( protein compared to about %!( in egg, ).*( in milk and &'+( in rice and wheat. $oreover, it is wholesome, tasty, highly nutritive and an e cellent source of essential minerals, vitamins and essential amino acids. At present about )%( of the total animal protein supply in the Asian region is in the form of fish protein. For the poorest segments of the population, fish is not only the most important animal protein source, but often the only one. 1.2 High Multiplication Capacity and Minimal Wat ! R "ui! m nt The reproductive potential of fish compared to any other farmed animal is also very high. A kilogram of female cultivable carp species yields on an average about ".% million eggs, each of which has the potential to become % kg fish in about a year. ,o livestock animal possesses this magnitude of fecundity. Although fish needs water as a medium to survive and grow, it consumes minimal quantity of water compared with any livestock or agricultural crop. Fish also enriches the water with its voided metabolites thus making the water more productive for agriculture. 1.# $o% &n !gy R "ui! m nt 'o! (!ot in (!oduction Fish culture systems require a relatively less amount of energy for protein production than any other farming system. -arp culture, depending upon culture practices, requires energy at the rate of !!'.&+ /01g of protein production while a land animal farming system needs over **" to ) ."" /01g. 1.) Wa!m Wat ! 'a*ou!s Fish +!o%th Fish are cold blooded or poikilothermic animals. 2n other words they cannot maintain a constant and high body temperature like other livestock animals. 2nstead, their body temperature fluctuates according to the surrounding temperature. 2n warmer climates, their metabolism accelerates and they grow faster, while in colder climates, the metabolic rate slows down, resulting in a reduced rate of growth. 2n this way they save energy by not spending it for maintaining a higher and constant body temperature. 1., -"uacultu! (!oduction (ot ntial Although the world3s total marine production now stands at more than +" million tons per year, all trends indicate that a saturation point is quickly approaching. 4uring the past decade the growth rate hovered around !(, much lower than earlier decades. 5n the other hand, tremendous potential e ists in aquaculture. Aquaculture presently produces over + million tonnes of fish and shellfish annually. 2t is estimated that Asian aquaculture production could be raised to !"')" million tonnes a year by the end of the century. Aquaculture production has increased at an annual growth rate of nearly 6( between %76*'+.. 1.. &mploym nt (ot ntial Aquaculture is also considered to be a potential source of employment for poor farmers and displaced capture fishermen. 8apid development of aquaculture has already generated considerable employment through culture of marketable fish, fish seed production, and marketing of fish and fish seed. The ,ational Agriculture -ommission of 2ndia while estimating the employment potential of fish culture has indicated that every tonne of fish produced provides employment to !.* persons. The other important advantages of fish farming are that the production is carried out within easy reach of consumers and also the harvesting can be ad9usted to demand, thus minimising distribution problems and spoilage. 8ural ponds in Asia, hitherto producing at subsistence level, have succeeded in increasing production per unit area through improved culture practices involving higher stocking densities, polyculture combinations, pond manuring and feeding. The switch over from monoculture practice to polyculture has significantly contributed toward higher production and the prospect of polyculture appears very bright as the fish seed of desired species is becoming easily available due to the establishment of a large number of hatcheries. 4uring recent years, advances have also been made in traditional aquaculture systems practised in rural 2ndia by the development of composite fish culture, a system of polyculture of a group of complementary and supplementary freshwater species of fast growing carps in undrainable ponds. #ith the successful demonstration in different agroclimatic zones of 2ndia, gradual improvements in technology have been made and it is now possible to obtain a production rate of over %" t1ha1yr in e perimental ponds and up to about * t1ha1yr in farmers3 ponds against the traditional average rate of production of &"" kg1ha1yr. To meet the increasing demand of seed of culturable carps, hypophysation techniques have also been developed for both 2ndian and -hinese carps and as a result they are now being bred in captivity even by fish farmers in remote villages. The emergence of this culture technology suitable for undrainable ponds and the simultaneous development of hypophysation techniques for fish seed production has completely revolutionized fish farm productivity. This manual intends to provide the basic concept and practical guidelines of fish culture in undrainable ponds. :ince it is prepared especially for e tension agents and field workers, certain important things have been repeated and at times e perimental results have been simplified with a view to making it more practical, simple and illustrative. 2t outlines the practices of procurement and propagation of fish seed, rearing of spawn to fry and fingerling stage, and production of table-size fish following simple sequential steps. ;ike other farming systems this culture system is also prone to certain une pected hazards for which one has to be prepared and properly equipped. :uch hazards are disease outbreaks, o ygen depletion, pollution, flood, drought, poaching, etc. The content of this manual is a synthesis of the author3s personal field e perience, the information gathered from published literature, and the observations of other workers in 2ndia. <ased upon 2ndian e perience, water resources in other developing countries with similar agroclimatic conditions may be utilized for the development of fish culture. 2t is hoped that this manual will serve as a practical guide to e tension workers in popularizing freshwater fish culture in undrainable ponds. 2. (RINCI($&/ OF FR&/HW-T&R FI/H CU$TUR& An understanding of the following basic principles of freshwater pond fish culture is essential. 2.1 (ond cosyst m ;ike agriculture, fish culture is also based on a series of processes involving reception and transformation of solar energy. 2n the pond ecosystem solar energy is utilized for primary production by chlorophyll-bearing plants such as planktonic algae and macrophytes. This conversion of solar energy into chemical energy =food> is guided by the photosynthetic and chemosynthetic activities going on in the aquatic plant community and the rate at which this is carried out is called primary productivity of that ecosystem. A part of the primary production is cycled through different trophic levels resulting in fish production. ?ere comes the community of consumers that comprise microscopic as well as large animals, which are unable to synthesize their own food and feed upon primary producers. 4ifferent forms of pond life are linked together through predator-prey relationship =Fig.%>. This chain of food production, which follows a general pattern, primary producers herbivores-carnivores - appears too simple and straight. <ut, in fact, it is a comple food web with various cross linkages. Fish populations may be classified into several trophic levels, depending upon their position in this food chain. @hytophagous fish such as grass carp and silver carp belong to the second trophic level as they feed upon the first trophic level organisms. ;ikewise, zooplankton, feeding upon phytoplankton, also belong to the same category. -arnivorous fish communities thriving upon zooplankton or herbivorous fishes occupy the third trophic level while other predatory fishes preying upon carnivorous fishes belong to the fourth trophic level =Fig. !>. A relatively simple food chain operates in fish ponds, but a comple one occurs in lakes and other larger aquatic ecosystems. The picture becomes even more complicated in large water bodies such as rivers and seas where comple food chains are referred to as food webs which in fact represent several interconnected food chains. There are some fishes which occupy mi ed positions, between different trophic levels. They consume both plants and animals and as such, cannot be naturally categorised into any one particular trophic level. A properly managed pond presents an e ample of a simple food chain under simple conditions. ?ere the number of food chains is reduced by encouraging the growth of phytoplankton. The macrophytes such as rooted green plants, floating plants, etc., are not allowed to grow. @hytoplankton is consumed by the zooplankton in the water column, whereas its detritus is utilized by benthic invertebrates. @hytoplankton, zooplankton, detritus and benthic organisms serve as food for the stocked fishes such as the desired carp species. Thus, as much of the available solar energy as possible is utilized for fish production by proper pond management. @rimary productivity is dependent on light, carbon dio ide, temperature and essential nutrients, each of which can be a limiting factor. 5f these factors affecting primary production in ponds, the one that can be manipulated easily is the quantity of nutrient elements through the application of nitrogenous, phosphatic and potassic fertilizers, as in agriculture. 2n ponds, only the top ! to * cm of soil is concerned with nutriention e change, and the soil below plays a negligible role in the production cycle. Andrainable ponds receive dissolved nutrients and sedimentary particles carried by rain water from the catchment area. <esides, production and decomposition of minute plant and animal organisms in ponds also modify the properties of the pond bottom to a great e tent. The nature and quantity of fertilizers determines the species composition to be used in a culture system. At low phosphate concentration, diatoms are common, but with increasing concentrations green algae become more frequent, eventually giving way to blue-green algae. 2n addition, e cessive phosphate gives rise to phytoplankton blooms which check the light penetration and thus lower the pond productivity through BautoshadingC =@rowse, %7&+>. Figure %. @ond Dcosystem . it is partially reflected and partially transmitted into the water where part of it is utilized in the process of photosynthesis and the rest is scattered or absorbed by suspended particles.*& 7. suffers from o ygen depletion causing critical stress conditions for the fish.+& 6. it is important that primary producers must provide o ygen to support the total biological respiration during darkness and also during the less favourable =warmer. overcast or rainy> days apart from providing food for the second and third trophic-level fish. %7+"> T mp !atu! 01C2 %* %& %6 7.)6 /olu3ility o' o4yg n 0mg5l2 !& !6 !+ T mp !atu! 01C2 6. Thus.6* /olu3ility o' o4yg n 0mg5l2 . 2n turbid waters. Food @yramid . thus allowing the light penetration only to shallow depths.77 6. #hen incident light strikes the water surface.6& 7. The bottom layer of water. being devoid of photosynthetic plants and also being in close contact with the decaying organic matter. Table % :olubility of o ygen under different temperatures at 6&" mm of ?g pressure =Adapted from A@?A.ight energy is one of the ma9or inputs in primary production and hence the success of fish culture depends largely on the efficient utilization of incident light. The rapid disappearance of light in such waters affects adversely the growth of diatoms. more light is scattered or absorbed.Figure !. #@-F. A##A. light is the most essential source in photosynthesis where penetration into the water column is regulated to a large e tent by suspended or colloidal particles =turbidity> and also by dense plankton levels.water temperature is more than that at )"H. Transfer of o ygen from air to water will occur when water is undersaturated with 45. phytoplankton blooms or algal scums limit light penetration causing reduction in photosynthetic rates. including undrainable fish ponds.".+. thereby reducing the availability of o ygen to fish.%+ %7 !" !% !! !) !. the diffusion of o ygen into the pond water is very slow. and chemical processes =Fig. a greater proportion of o ygen is used up for their respiration. they also respire and consume o ygen. 2n natural waters.)+ +. 6.&. 5 ygen production by phytoplankton is greatest near the surface and decreases with the increase in depth because of self-shading. The saturation value for dissolved o ygen available for fish life at !"H. even in waters with adequate nutrient concentrations. The air above the pond water surface may be considered to have a more or less constant percentage of o ygen.! 6. 45 values are constantly changing because of biological. Thus. it creates a wide fluctuation in the . Eariations in concentration of dissolved o ygen may occur due to the following three important factorsF • • • the saturation level of o ygen in water decreases as the temperature risesG supersaturation is an unstable state.&+ +.%+ 7. they also respire and consume o ygen throughout day and night. hence the most important source of o ygen is that generated during photosynthesis. At times the pondwater is supersaturated with o ygen during the day.%% !7 )" )% )! )) ). physical. !* 7.*) 6. while during the night. 4issolved o ygen =4o> concentration is always high at lower temperatures and gradually decreases with increase in temperature."% +. 5n the other hand. and o ygen will diffuse from water to air when water is supersaturated with o ygen.2 O4yg n 3udg t The concentration of dissolved o ygen in the water.%) 6. )>.. ?owever. which depends on the temperature.!* +. and plants not only photosynthesize to produce o ygen. the partial pressure of o ygen in the air may vary slightly at a given location because of differences in atmospheric pressure. :ometimes. +. ?owever. the situation becomes much more comple . 2. is an essential component of the aquatic environment to govern the carrying capacity of a pond. e cept under conditions of strong turbulence. these are additional sources of o ygen at daytimeG but on the other hand.)! 6. which is a highly unstable state. As discussed earlier. )* 6.at a particular atmospheric pressure =Table %>.*) +.!! 6. #hen heavy infestation of aquatic weeds and dense bloom of plankton occur. Ander aerobic condition. with a simultaneous depletion of 45. adversely affecting fish life. Therefore.level of dissolved o ygen. decomposition also occurs under anaerobic conditions. Aerobic decomposition of organic matter by bacteria is also an important drain on the o ygen supply in ponds. the situation in terms of availability of 45 becomes worse. Figure * shows a situation created by algal bloom or weed infestation where wide variations between actual and e pected o ygen production do occur =Figs. but at night this surplus level drops down to critical level. At times high rate of bacterial decomposition of dead organisms and other organic bottom deposits lead to a condition favouring the increase of the level of carbon dio ide and other abno ious gases. ?owever.. the end product of decomposition is primarily carbon dio ide. but the rate of degradation of organic matter is not as rapid and complete as under aerobic conditions. resulting in fish kills and planktonic collapses =8adheyshyam et al. 4uring cloudy days. . and *>. . &>. Aerobic decomposition requires a continuous supply of o ygen and proceeds more rapidly when 45 concentrations are near saturation. under such situations o ygen production increases to its ma imum during the daytime leaving surplus for the fish even after consuming for their own respiration. when the incident light is inadequate for phytosynthesis. 2n fact. Ander conditions of heavy algal blooms and weed infestation. %7+&>. the phytoplankton and aquatic weeds actually consume more available o ygen during day and night than they produce during the whole day =Fig. it is important that the pond water should provide adequate o ygen to support the total biological respiration during the hours of darkness. Figure ). 5 ygen -ycle in @ond . Dffect of Algal <loom on 5 ygen @roduction .Figure .. 4ial 5 ygen @roduction1-onsumption @attern under Algal <loom1#eed 2nfestation .Figure *. :election of the species should be based on the productivity of a pond. The principal considerations in species combination are that they have complementary feeding habits. they occupy different ecological niches.# D si!a3l 'ish sp ci s 'o! cultu! The choice of fish species is very important in ma imizing production. 2t is obvious that any single species cannot utilize all the available food in a pond because of its specific feeding habit and hence a combination of compatible species with complementary feeding habits are usually stocked to make better use of the natural food available in the pond. availability of artificial food resources. :ince considerable amount of energy is lost in successive trophic levels of the food chain.Figure &. the latter being mostly e cluded because of their longer food chains. <ecause of this. both in terms of quantity and quality. $i ed species farming or polyculture yields a higher production than single species farming. 8elation between :tocking 4ensity and @roduction 2. herbivorous fishes are always preferred to carnivorous fishes. efficient fish culture always aims at making the chain as short as possible. availability of seed and the marketing prospects. they . #ith efficient removal of such metabolites by aerating the pond water. as there is better utilization of the available food. si species of fish viz. water tends to stagnate and in hot weather tends to heat up quickly. catla =-atla catla>. and most profitable. better cooling action by wind. 2n smaller ponds. 2n undrainable ponds. the total crop becomes dependent on the primary production and in such cases simply by increasing the stocking density. 5ther similar combinations may work 9ust as well. but in such cases the individual weight and size is reduced.ormally fish production increases with the increase in the number of fish stocked per unit area upto a level and then starts decreasing =Fig. silver carp and common carp =-yprinus carpio> are stocked together so as to utilize most of the fish food organisms present in the pond =. @untius sp. under composite fish culture. %76%>. and monose Tilapiamossambica grew bigger in ponds of a larger area indicating the living space phenomenon =-hen and @rowse. 2ncrease in stocking density simultaneously increases the total o ygen demand with obvious dangers. the zooplankton feeders are included in the combination.! ha pond will be more than double that of a ". /toc6ing d nsity7 . the zooplankton-feeding bighead carp =Aristichthys nobilis> and the weed-eating grass carp =-tenopharyngodon idella> is well known in -hina and :outheast Asia. ?igher stocking density results in increased total production. the rate of production in a ". Fish under stress e hibit decreased feed consumption and slow growth and are predisposed to many parasitic and microbial infections. 5n the other hand. %76%G :inha et al. despite the fact that the stocking rate per unit area is the same and all other management components including the genotype of the stocking materials and ecological conditions remain the same. The combination of the phytoplankton-feeding silver carp =?ypophthalmichthys molitri >. . . thereby enhancing production. 2n other words. the stocking rate can be increased further.abeo rohita> and mrigal =-irrhinusmrigala> along with three -hinese carps such as grass carp. but the most important aspect is to try to establish a balance between the species based on the food spectrum of the pond =:inha. The ponds having larger surface area are sub9ected more often to wind action resulting in greater rate of diffusion of atmospheric o ygen into the water. Dven with supplementary feeding the scope of increasing stocking density and fish yield is limitedG it increases to an optimum level and then starts decreasing.) $i*ing spac 2t has been observed that under identical conditions of management levels and stocking density fish grow bigger in larger ponds. in a production which is highest in quantity and quality of fish.% ha pond.arger ponds have other advantages also.akshmanan et al. 2n $alaysia.. grass carp. viz. 2n ponds where no artificial feed is used. the increase in the total production is not possible. %76&>. rohu =. usually a year. 2n 2ndia. and they be non-predatory in nature. lower stocking density yields larger individual fish. %76)G -haudhuri et al. Ander crowded conditions fish compete for food and space and are stressed due to aggressive interaction. 2.attain marketable size at more or less the same time.. %7&&>. accumulation of e cretory products of the fish population also suppresses their growth rate. @roper stocking rate for a pond is that optimum level which results in a given time. they tolerate each other.. A combination of plankton and macrophyte feeders is most usual. Angrazed phytoplankton is fed upon by zooplankton and to utilize them. &>. arge ponds are difficult to fill and even more difficult to harvest. the use of ammonium sulphate in low doses is usually recommended. supplementary feeding is indispensable. . viz. 8ecommended optimum size is ". Though there is a considerable loss of nitrogen from the ammoniacal form in alkaline soil. (ond ' !tility 5rganic matter and mineral constituents of the pond soil supply the required nutrients for chemical and biochemical production processes. since it is brought to the soil by different processes. Iet. This is the single most important management component for increasing production... :ometimes such nutrients are not available in sufficient quantity in the pond and hence they are added from outside in the form of fertilizers. the ratio of organic carbon to total nitrogen =-1. ammoniacal or nitrate is also very important. There must be an optimum size and shape of the pond to balance size with practicability of management. a little potassium when added to the pond. 2n intensive and semi-intensive culture of fishes.. 2n this conte t. atmospheric electric discharges and photochemical fi ation are some of the potential sources of pond nitrogen. %7+*>. when nitrogen is added from outside. the . there is a physical limitation. stimulates the production of plankton. ?owever. . the fi ation of atmospheric nitrogen by blue-green algae is of considerable importance. 5rganic matter of the pond sediment is also an essential factor regulating the bacterial activity. The quantity of feed and the form in which it is offered affect the rate of consumption. 2t is advisable to use the ammoniacal form of nitrogen in acid and neutral soils and the nitrate form in alkaline soil =:aha. ha ' %. Temperature. affect the rate of food consumption.. etc. /uppl m nta!y ' ding #ith the increase in carrying capacity of the pond either by aeration or circulation of water. keeping in view the role of sulphate in reducing the soil alkalinity. :ince plankton production is often limited by inadequate quantity of phosphorus which is essential for the assimilation of nitrogen into cellular matter.e. phosphatic fertilizers are widely used in fish culture." ha =:inha and 8amachandran. ratio> is important. 2. 2n a tropical climate. fish growth can be increased further by supplementing the natural food with some artificial feed. 2n ponds it is easily available both in soil and water and does not form insoluble salts and is rarely deficient e cept in acid peaty soil. availability of nitrogen does not depend on the inherent status of soil. @eriodic application of organic manures ensures to a certain e tent replenishment of nutrients and also provides an energy base for bacterial activities. Anlike phosphorus. The pond bottom also provides a suitable environment for the decomposers like bacteria and fungi to mineralise organic components of the pond sediment and release soluble nutrients. large enough to allow proper growth of fish. crowding and health condition. its form. dissolved o ygen level.Though it is preferable to have ponds of a large size. i. 2. bluegreen algae. Apart from this.. %7&7>.itrogen fi ation by azotobacteria. @otassium is the other essential nutrient for plant growth. but at the same time small enough to be manageable. The above basic facts need careful consideration while planning for freshwater pond fish culture. All such factors affect fish health and contribute to the risk of disease outbreaks. 4rainability imparts a very desirable feature to a pond and some authors prefer to call only the drainable type of ponds as fish ponds. They may be further classified as drainable ponds and undrainable ponds. if they do so seasonally. ranging from supplying drinking water for human population. ?ence. 2. The habitat of an undrainable pond is very varied and dynamic. 2ndian e perience has shown that e perimental fish production to the tune of over %" tonnes1ha1yr can be achieved even from such undrainable ponds through a proper understanding of the biotic and abiotic components of the ecosystem and adoption of suitable culture technologies. shallow and seasonal ponds get filled or dry. <oth flood1 rain and drought influence the ecosystem of the ponds on such lands. etc. sometimes result in nutrient accumulation. increased feeding. left-out feed materials and organic load of the pond bottom can affect certain e posed vital organs and tissues of fish. #ith the onset of monsoon. frequent appearance of algal blooms.organic matter and the bacterial flora are also directly consumed by zooplankton and some fish species. . torrential downpours sweep across the land and the amount and frequency of rain decrease towards the end of the monsoon. before adopting any culture technology. CH-R-CT&RI/TIC/ OF UNDR-IN-9$& -ND DR-IN-9$& (OND/ 2n 2ndia ponds are relatively small and shallow bodies of impounded water with limited wind action. A fish farming system is unique in that the farmed animal is poikilothermic and lives in water where respiratory o ygen level compared to air is limited and becomes critical at times. etc. As a result of such water quality and environmental problems. community structure and community metabolism. depending upon the drainage facility by gravity. live stock.. They may be called perennial if they retain water the year round or temporary1seasonal. the infectious diseases and their control assume importance. dissolved o ygen deficiency and other water quality problems in undrainable ponds.. to supplying water for agriculture. but can be monitored and managed for increasing fish production. whereas deeper perennial ponds e hibit considerable fluctuations in water levels accordingly. #. it is imperative to have an idea about the basic biology of the pond types in terms of environmental factors. Further. ?owever.8 Dis as s and th i! cont!ol Earious intensification approaches such as increased stocking rates. #. :evere floods may occur. fertilization programmes. :mall. whereas a late monsoon or early monsoon of short duration may result in serious drought.1 Und!aina3l ponds The periods of Bplenty rainC and Bno rainC usually prevail in regions having undrainable ponds. Though these ponds are basically constructed for storing water in such areas for multiple uses. metabolic waste products. recent trend is to utilize them for fish culture. The description of the undrainable ponds is based upon the studies conducted at the -entral 2nstitute of Freshwater Aquaculture, 4hauli, <hubaneswar, 2ndia, under an e tensive environmental monitoring programme of rural undrainable ponds. #.1.1 + n !al mo!phom t!y Andrainable ponds in general are relatively small, perennial or seasonal water bodies constructed or e cavated for multiple uses. :ome of these ponds have proper embankments. They greatly vary in their dimensions ranging from "."! ha to over !.* ha in water surface area and *" cm to !*" cm in depth. ;arger ponds are relatively deeper while smaller and seasonal ponds are shallower. Anlike shallow seasonal ponds, the bottom of the perennial ponds is never e posed to sunlight and therefore the whole ecosystem of such ponds is quite different from those of shallow and seasonal ponds. Ase of these ponds by villagers for multipurpose provides the source of organic enrichment. Asually the only source of water for these undrainable ponds is the heavy rainfall during the monsoons. ?owever, in some cases, the pond bottom is cut below the water table so that ground water enters the ponds. As soon as the monsoon ceases, the water level starts decreasing gradually and shortage of water is quite common during the pre-monsoon season. #ater is lost from the pond through evaporation, seepage and transpiration by aquatic macrophytes and the trees and shrubs planted along the pond sides. $acrophytes tend to appear in both perennial and seasonal types of ponds but with increased intensity in shallower ponds. @resence of thick sediment layers in the bottom is the most characteristic feature of these ponds which gradually get accumulated during the course of time and vary between a few centimeters to over a meter and half in thickness. The quality and quantity of sediment deposition depend mainly upon the original soil, method of construction, nature of embankments, macrophyte cover, pond productivity, organic and inorganic additions, species cultured, etc. Although sedimentation is relatively faster in smaller ponds, there is a positive correlation between the age of a pond and its sediment thickness. #.1.2 (hysico:ch mical n*i!onm nt The water depth and total volume of water available for individual fish are crucial in fish culture systems. Adequate water depth is needed not only for optimum growth, but also to provide enough space and o ygen for fish life. #ater levels in these ponds are mainly dependent upon monsoon rains. After the monsoon season, the water level starts decreasing gradually and shortage of water is quite common during the summer season which is the most crucial time for fish culture since the fish growth rate is faster in this period. 2n fact, during the time of lowest water level the ponds contain the ma imum biomass. 2n shallow and seasonal ponds, sufficient phytoplankton population fails to appear and the soft sediment layer is vigorously stirred up by fish, making the water more turbid, thereby reducing the photosynthetic process by limiting light penetration. Dventually, the total amount of available dissolved o ygen may not be, at times, sufficient to meet the demand for total community respiration and the chemical o ygen demand of the sediment, resulting sometimes in mass fish kill and planktonic collapse =8adheyshyam etal., %7+&>. 5n the other hand, in deeper perennial ponds where the water column is more than ) m, fish life is again adversely affected. 2n such ponds the photosynthetic or o ygen producing zone is less in comparison with the o ygen consuming layer. 2n addition, the sediment proper and the sediment community also consume a considerable amount of o ygen. All such conditions lead to a negative o ygen balance. The water in most of these ponds remains slightly alkaline =p? 6."'7.">. The ,? .-, =ammonia-nitrogen> content of the waters remain below "."! mg1l with even lesser quantities of ,o)-, =nitrate-nitrogen>. The @o.-@ =phosphate> concentrations remain low and these chemical features of such ponds suggest that these waters are highly nutrientdeficient, particularly in nitrogen. 5n the contrary, the pond sediment is rich in organic and inorganic nutrients. The organic carbon ranges between ) =in newly e cavated ponds> and *" mg1g dry sediment weight =in older ponds>. The nutrient status of the sediment differs completely from that found in the overlaying water column =5lah, %7+)>. 2n general, all the basic nutrients in the pond sediment are about thousand times higher than in their respective water column. -arbon dio ide and o ygen are the most important gases affecting the pond community including fish. 4uring the photosynthetic activity, carbon dio ide is usually at zero level while during the darker period its concentration increases. At higher concentrations it may be to ic to fish life. -arbon dio ide to icity increases with decreasing level of dissolved o ygen. -arbon dio ide concentration can be tolerated upto !"')" ppm in these ponds provided o ygen is near saturation. #.1.# Community st!uctu! and 'unction <acterioplankton and phytoplankton constitute the basic food for the fine filter feeder fish species and also for the zooplankton which form the main food of the rough filter-feeder species. The bacterioplankton population is always higher in those ponds which are associated with the activities of larger human and livestock populations. $ost of the relatively older ponds with frequent appearance of $icrocystis bloom have higher levels of bacterioplankton population =)'%" million1ml>. 5n the contrary, the newly constructed and recently desilted ponds have less dense bacterioplanktonic community, around %'! million1ml. $acrophytic infestation also significantly limits the bacterioplankton production. The planktonic detritus originates mainly from decomposing fragments of the phytoplankton and zooplankton and has generally a concentration range of ! """ ' !" """ number1l. The main groups of phytoplanktonic population are $y ophyceae, -hlorophyceae, Duglenophyceae and <acillariophyceaeG whereas copepods, cladocerans and rotifers constitute the ma9ority of zooplanktonic population. :ome of the very old ponds having e cessively thick sediment layer face $icrocystis blooming. 2n such ponds the benthic animal fauna is represented by a very small number. 2n the ma9ority of the ponds the benthic animal communities are dominated by red chironomids and oligochaetes indicating the general o ygen deficiency in the sediment layer. The bacterial decomposition and nutrient recycling in ponds are greatly influenced by the anaerobic nature of the sediment. At the initial stage of $icrocystis bloom in older ponds, the o ygen production has been found to be the highest =%> =over %* g 5 !1m >, whereas the total community respiration remains considerably low =!> =below %" g 5 !1m >. ?owever, during the active decomposition stage of $icrocystis =plantonic collapse stage> the total o ygen production level goes lower =)> =*'& g 5 !1m > than that of the community o ygen consumption =.> =&'6 g 5!1m >. 2n older ponds, especially those having thick anaerobic sediment, the biochemical o ygen demand ranged between 6"( and 7"( of the total o ygen production, ultimately causing ano ic condition leading to fish kills. ! ! ! ! The ma9ority of rural undrainable ponds are characterized by anaerobic benthic sediments. The dead and decaying organic matter settles down to the pond bottom =sedimentation> where it is sub9ected to further decomposition and mineralisation. The upper layer of the sediment remains aerobic while the deeper layers are deficient in o ygen and thus anaerobic. :ome of the distinguishing features of drainable and undrainable ponds are summarised in Table ). These perennial undrainable ponds in tropical monsoon lands with yearround warm water under plenty of light offer an e cellent possibility for fish culture. $ost of the species cultured greatly depend upon natural fish food resources and with a limited dependence upon artificial supplementary feed. ?owever, without proper environmental management, the water remains infertile due to the overall nutrient deficiency with a very pronounced nitrogen limitation, although they possess a very high production potential. 5n the contrary, the pond sediments have e tremely high level of organic nutrients in almost locked-up conditions which remain unutilized due to the anaerobic nature of the pond bottom =Fig. 6>. ?owever, though regular raking up of the pond sediment, either by manual or biological means, the organic nutrients could be released for making the pond water more productive. @roper management methods can optimise fish production in perennial ponds at most economical rates while seasonal ponds can suitably be utilized for fish seed rearing and also for short-term fish production depending upon the duration of water retention. The general feature of the properly managed and ill-managed undrainable fish ponds are shown in Figures +a and +b. #.2 D!aina3l ponds @onds which can be supplied with water and drained of its water according to the requirements of the fish farming operation are known as drainable ponds. These ponds require suitable ground with proper embankments, inlet and outlet structures and adequate supply of water on regular basis. :tudies conducted on the filling up of ponds from various sources of water supply showed the following cost figures =Table !>. Figure 6. $icrobial 4ecomposition @rocess at the :ediment - #ater 2nterface #ell $anaged @ond .Figure +a. > (a!am t !s #ater p? Total alkalinity =mg1l> Ammonia-nitrogen =mg1l> ."!" ".itrate nitrogen =mg1l> @hosphorus =@5.""* ' "." ' 7.""* ' ".!* .! ++ ' !"" ."*" D!aina3l ponds 0co%dung t! at d2 6. %7+)G 8adheyshyam.Figure +b.%&" .-@> =mg1l> @lankton Und!aina3l ponds 0natu!al condition2 6.!" ".6 ' +. biological and functional characteristics of undrainable and drainable rural fish ponds in 5rissa province of 2ndia =5lah.""* ' ". <adly $anaged @ond Table ) -hemical." *" ' !*" ." ' ".)"" .comm.""% ' ".". pers.""* ' ". 6 !"" kg1ha1+ months and over %" tonnes1ha1yr have been achieved in composite fish culture trials conducted in different agroclimatic conditions of 2ndia.).et production =g carbon1m!1day> -ommunity respiration =g carbon1m!1day> :ediment o ygen consumption =g o ygen1m!1day> *7 ' ) 7%% %!. .%6&& ' ).)+* ' !.%* ' %7 "77 !.&& ' %%. supplementary feeding and health care.+6* !.1 Ca!p cultu! The most successful system of pond fish culture is the polyculture of three 2ndian ma9or carp species . ). modifications are often made in stocking density.77 %.+. 5n the basis of growth performance of different species. silver carp.)6 ' !.7 " ' ! &&" ) ' +&" %% ' !"7 %..!&% ' &.+* ' +. ?igh rates of fish production to the tune of over * *"" kg1ha1& months.catla. The best results in terms of fish production in this system results not only through a 9udicious combination of species.@hytoplankton =number1l> Jooplankton =number1l> <acterioplankton =million1ml> <enthos =number1m!.%% =->!. species ratio."! ' %".6& ' %". but also due to appropriate management techniques including pond fertilization. ' ! 66" %. loss1day> <ottom =( dry wt.. The carp culture system as a whole is operated as a three-tier culture system where the practices are adopted for rearing fish during their different stages till they are harvested. 2n 2ndia this is commonly known as composite fish culture. loss1day> Kross production =g carbon1m!1day> ."6% ". fertilization schedule and supplementary feeding programme in different agroclimatic conditions.> 4ecomposition rate of Dichornia leavesF :urface =( dry wt.77 =->%. grass carp and common carp.++ ' ). ' %.*.)* %. .*%.+& %.) !.! ' %!. %. ' !..)%! % .++6 ' 6.+& . (R&/&NT (R-CTIC&/ OF FI/H CU$TUR& IN (OND/ ).!7 ' %. rohu and mrigal along with three -hinese carps viz.7. 8elatively smaller. Fry raised in nurseries are reared upto fingerlings in slightly bigger ponds =".. The fish not only utilize spilled animal feed but also directly feed on fresh animal e creta which is partially digested and is rich in nutrients.2 Int g!at d ca!p 'a!ming An integrated approach of composite fish culture together with compatible combination=s> with poultry. """'* """ kg pig meat Fish p!oduction -nimal p!oduction 0li* % ight2 The salient features of the various types of livestock1carp integrated culture systems are described below.'* ton1ha &" """'6" """ eggs L % *""' ! """ kg meat ) ' ."* ' ". Annual production through integrated carp livestock farming Int g!ation Fish L @ig farming Fish L 4uck farming Fish L @oultry farming .:pawn =post larvae> are reared upto fry =!') cm> stage in nursery ponds.> of fry are usually taken during the season. Table . poultry. %767G %767a>. fry to fingerlings =+'%! cm> in rearing ponds and finally fingerlings to table-size fish in composite fish culture ponds or stocking ponds. ). @roduction potential through integrated carp farming is summarised in Table . are integrated with composite fish culture by siting animal housing units on the pond embankments in such a way that the animal wastes and washings are diverted into fish ponds for recycling. :everal crops =)'. Fertilizers and supplementary feed are not used.. seasonal ponds are mainly used for rearing spawn to fry stage and harvested after !') weeks. resulting in drastic cost reduction =:harma et al. Fingerlings are removed after ) months and stocked in composite fish culture ponds. ducks.1 Int g!at d 'ish : pig 'a!ming @igstyes are constructed either on the pond embankment or near the pond to facilitate easy drainage of waste directly into the pond which acts as pond fertilizer and supports dense . viz. pig rearing and cattle raising is now being adopted.. etc. Ander this system of farming small livestock and farm yard animals. pigs. ton1ha *"" kg duck meat L %6 """'!" """ eggs & ' 6 ton1ha .2. :urplus e creta supports the rich growth of planktonic fauna. ).% ha> of seasonal or perennial in nature. duckery. @ond fertilization by cattle manure and feeding with %F% mi ture of oil cakes and rice bran is the usual practice. ormally !') months old ducklings are preferred. $arketable size fish are sold by partial harvesting while final harvesting is done only after %! months of farming. . #hen given free range. fish also feed directly on the pig e creta. The duck droppings like pig e creta act as fertilizer. About ! months-old weaned piglets are fattened for si months when they attain slaughter size =&"'6" kg> and similarly a second crop is raised within the ne t si months. A duck house is normally constructed on the pond embankment or on the pond water on a floating platform =Figs. weeds. etc."F!"F)"F%". bottom feeders and grass carp in the ratio of . column. @onds are prepared and stocked with fingerlings of all the si carp species at & """ ha with surface. About !""'. ). column.2. %"A and %"<>.%> and stocked with fingerlings of all the si species of carps cultured under composite fish culture at higher of + """'7 """1ha with surface. . About )"' . 4ucks start laying after *'& months and continue for ! years.o other feed or fertilizer is applied to the pond. Fingerlings of over %" cm are preferred for stocking."F!"F)"F%". <esides. they are also provided with duck feed at the rate of %"" g1bird1day. Krass with interlocked soil in root system =sod> are provided once a week to avoid mineral deficiency. Although ducks are able to feed upon natural food from the pond. Fish yields ranging from ) """'* """ kg1ha1yr are generally obtained. @ond preparation technique is basically the same. tadpoles. @igs are fed on mash at an average rate of % kg1day. bottom feeder and grass carp in the ratio of . ducks feed on aquatic organisms such as insect larvae.7A and 7<>. ."" ducks are sufficient to adequately fertilize a l ha pond. Fish yields ranging from & """'6 """ kg1ha1yr are generally obtained. Kreen grasses or animal fodder is also provided. A pond is prepared by following the usual pond preparation techniques =:ection 7. Krass carp is fed with aquatic weeds or green animal fodder." pigs should be kept for proper fertilization of the pond.growth of natural fish food organisms =Figs. molluscs.2 Int g!at d 'ish : duc6 'a!ming This is also an efficient integrated system based on the principle of waste recycling. Figure 7a. Fish-cum-pig farming =wooden pigsty> . Fish-cum-pig farming =concrete pigsty> .Figure 7b. Figure %"a. Fish-cum-duck farming =duck house in pond> . this system of freshwater fish culture has assumed greater significance in view of its potential role in recycling of organic wastes and in integrated rural development =:inha.ft. The chicken house can also be built directly over the pond water so that the e creta may fall in the pond water underneath. The droppings of the birds fall on the floor from where these are collected and applied to the pond. %7+%>. per bird. .Figure %"b. The space requirement in such a system of poultry raising is about % sq. 2n 2ndia.o feed or fertilizer is applied in the pond. there are many low-lying areas which become waterlogged during the rainy season. . Fish production at the rate of .2. 2n course of time these areas get infested with dense aquatic vegetation and turn into swamps. :wamps are also formed along the irrigation canals due to profuse seepage. Asually.""'&"" chickens1ha of pond water surface are used.'* t1ha is possible using this system. These areas are best suited for culturing airbreathing fishes such as . Fish-cum-duck farming =duck house in pond dyke> ). ). e cept aquatic vegetation for the grass carp.# -i!:3! athing 'ish cultu! <esides freshwater ponds.# Int g!at d 'ish : poult!y 'a!ming Ander this system of integration the poultry birds are raised in cages under a shed normally constructed over the pond embankments or in the vicinity of the pond. 2n intensive system of monoculture of magur and singhi with frequent change of water. ).etc. such ponds receive huge amounts of feed. -hanna striatus and -hanna punctatus> and /oi =Anabas testudineus>. but also encourage the growth of insects which are consumed by the fish. 4uring the course of culture operations.* m. 4uring raising of marketable size fish. The common culturable species are magur =-larias batrachus>. replenishment of water becomes an essential input in case of intensive system of culture in ponds where very high stocking rate and intensive feeding is practised to obtain very high yields =4ehadrai./oi =Anabas testudineus>./. The sewage fed ponds are generally dewatered completely during summer so as to remove all the carnivorous fishes.-a. 2n 2ndia itself there are about %*" sewage-fed fish farms covering an area of about %! """ ha. $onoculture as well as polyculture of these fishes are commonly undertaken. fertilizers and manures as critical inputs. $agur =-larias batrachus> and $urrels =-hanna sp. Fingerlings =&'%" g> and feed are the two material inputs used in the culture system. @roduction at the rate of over ) """ kg1ha1+ months is possible through monoculture of -hannamarulius in swampy ponds. #ithin a month the pond stabilises with respect to dissolved o ygen and becomes suitable for stocking with fish seed. @resence of naturally occurring weeds in airbreathing fish culture ponds not only provide protection against poachers. semi-intensive culture and intensive culture depending on inputs and level of management =4ehadrai. yields of over %* t1ha1yr have been obtained.. /amal and 4as.. %7+*>. Eery high production in the order of 6'%" tonnes1ha1yr has been obtained from ponds fed with sewage which invariably contains high percentage of .@. including sewage and waste water produced by the human community hold high potential for fish production. An average production of about 6 t1ha1yr is easily obtained using a mi culture of * carp species =Khosh et al. A portion of the organic production in the pond also undergoes death and decay and gradually adds to the pond bottom sediment.-TION OF &<I/TIN+ (OND/ The ma9ority of freshwater fish ponds in the 2ndian subcontinent are the dugout ponds of an undrainable nature which at times lack proper embankments. but due to slow bacterial action under prevailing anaerobic conditions the . singhi =?eteropneustesfossilis>. There are three levels of culture practices viz. R&NO. Fertilizer is not used. and sediment particles carried down by rain water from the catchment area. %7+*>. Thus. a thick sediment layer is formed reducing the depth of the pond. %767>. . murrels =-hanna marulius. ?owever.. low cost culture. $urugesen and @athak.) / %ag :' d 'ish cultu! The wastes. The pond is initially fertilized by introducing partially treated sewage effluent upto about 6*'+" cm and then clean water is pumped in to raise the pond water level to %.> without getting involved in costly processes of their reclamation essentially needed for carp culture. yielding production to the tune of ) """ to 6 """ kg1ha1yr. :inghi =?eteropneustes fossilis>. They are quite rich in organic and inorganic nutrients. additional fertilization with sewage effluent is carried out in small doses every month and the pond is netted frequently to help o ygenate the water and in course of netting the marketable size fish are also harvested. with the advancement of time. large floating weeds such as water hyacinth should be eradicated by pulling them out manually or mechanically.. This phenomenon of subsurface secretion is called percolation. 2n this period pond renovation can be carried out efficiently and economically. 2f the water table in the surrounding area is high. . etc. . several furrows or ditches may be made towards the lowest contour point where a pit may be dug out to drain all the percolated water =Fig. in order to make the ponds more suitable and to regain their fertility. . Thus. laborious and e pensive. 5ther rooted emergent or submerged weeds can be taken care of only after draining the pond. %%>. redressing and repairing the dykes. collection and removal of such weeds will require more labour and time. 2t is done by taking the level measurements at certain spots on the pond bed.'& years by removing sediment from the pond bottom. the following practical measures are recommended.) Contou!ing #here the bed is found to be uneven... .1 Wh n to ta6 up th ! no*ation %o!6 As soon as the water table of the area surrounding the pond goes down the renovation work can be initiated. <efore dewatering the pond.nutrients are almost locked up in the sediment and are not available for primary production. 5therwise. Further. contouring is necessary to estimate the amount of silt to be removed. :ummer is the most suitable period for this @urpose as complete drying of the water body is possible. For this... the anaerobic decomposition of the organic matter accumulated in the sediment releases harmful gases and depletes dissolved o ygen level in the water. 8emoval of slushy silt from the partially dried pond bottom is difficult. it becomes necessary to renovate the e isting ponds periodically every . @eriodical pumping of water from the pit facilitates keeping the bed dry. 2t will also help in redesigning the pond taking into consideration the highest flood level and ma imum rain water level.2 D % ding 2t has been observed that most of the rural ponds are not properly managed and become weed-infested in course of time. . 2n case the rate of percolation is high.# D %at !ing and d!ying 4ewatering of the e isting pond is possible either by draining the water after cutting a portion of the embankment or by pumping out. there is considerable inflow of water from the pond bottom. it would be better if they are connected temporarily to nearby natural or man-made drainage systems having relatively lower bed level for complete dewatering by gravity and making the entire area completely dry.. walking platforms made up of bamboos or wooden planks may be put on the slushy bed to facilitate desilting work.. R clamation o' d ! lict %at ! 3odi s 4erelict waters in millions of hectares. 2n some larger ponds it becomes difficult to dry the central portion of the pond bottom as it is nearer to underground water table. 2n case of larger water areas. are common sights in most of the :outh Asian countries. At this stage dried silt is cut and removed manually or mechanically and heaped at a suitable place for its utilization in agricultural fields. 4rained-out pond with furrows .. The te ture of silt is different from that of the bottom hard soil and cracks quickly. :uch untapped water bodies with potential for aquacultural production may be reclaimed and made suitable for fish culture by adopting more or less similar procedures. This helps in drying the silt and easy removal thereafter.. D silting After complete dewatering.Figure %%. . . #here complete drying is not possible due to high rate of percolation. lying unutilized. the pond bed is allowed to dry and develop cracks in the silt mass. 2n such cases the slushy and loose silt should be scrapped and spread to the sides with the help of wooden planks tied with ropes for pulling. the top width may be kept at a minimum of %. etc. 2t is necessary to provide permanent inlet structures wherever is possible. it is unsuitable for making dykes as it may be washed back in the pond. #hile raising the dykes. predators and unwanted species to enter and at times results in mass fish kills due to pesticide pollution. claylime mi ture or any other locally cheap cementing material. such spots should be properly repaired by stuffing binding clay. if such topographic facilities are not available. .. 4uring high rainfall or peak irrigation periods in canal-irrigated areas such ponds get inundated with water from the neighbouring agricultural fields causing stocked fish to escape. and especially at the time of renovation. CON/TRUCTION OF N&W (OND/ -ND F-RM/ Eillage ponds. The silt mass is very rich in organic and inorganic nutrients making it most suitable for application in agriculture and horticulture. 8ats and crabs cause great harm to pond dykes by making holes. 2t has been e perienced that such areas can also be successfully reclaimed and renovated by partitioning into smaller units by raising cross bundhs. D isting pond dykes should be repaired every year after the monsoon. <eing non-cohesive and unstable. levelled. :uch holes allow serious leakage and if not checked immediately.?owever. 4ue to poor consolidation. . homestead or backyard kitchen ponds. $oreover. may endanger the stability of the dykes. wave action due to wind also causes large-scale dyke erosion. ?ence. <y putting large floating aquatic plants such as water hyacinth along the sides of the dykes e posed to wave action during the windy season such erosion can be checked. rural ponds lack proper embankments. which however creates many management problems.8 Maint nanc o' dy6 s 2n general. farm roads. 2n relatively larger ponds. These areas should be covered with earth. -utting the dyke to allow water into the pond from the surrounding area without any secured screening is a normal practice. garden or farm ponds.* m with !F% slope =horizontalF vertical>. 2n e tensively large areas dewatering by draining or by pumping is not feasible. Dach newly formed unit then can be dewatered. occupy enormous . 4etails about inlet and spillway structures are described in :ection &. irrigation ponds and occasional ponds such as brick mine pits and quarries. heavy duty water pumps may be put into use for quicker dewatering. overflow of water occurs during heavy rains or flood. thoroughly rammed and grass turfed. These dykes should be properly raised and the height may be kept at a minimum of one meter above the ma imum water level recorded in that area. provision of proper dykes is a must. the dry period of the year also may not last long enough to permit the work to be completed. $ost of the traditional pond dykes are below the required heightG as a result. dried and desilted. etc. Frequent erosion in steep dykes during heavy rain or wind can be avoided by strengthening the inner sides of the dykes with poles or bamboos or corrugated cement planks. erosion from the top of the dyke during heavy rains usually results in grooving out of small channels... @eriodically. There are. A saucer-shaped area may be an ideal site for a large dug-out pond. The following three essential conditions guide the proper site selectionF • • • Topography :ource of water and its quality :oil type . even for undrainable ponds. 2n such areas construction cost is relatively low mainly due to limited earth cutting. . ?owever. .1 /it s l ction :election of suitable sites for fish farm construction is very important. The site should be easily approachable so that there may not be any difficulty in the transportation of input materials and in the marketing of the produce. it is mainly the topography of the site which determines the basic design of the pond1farm. The surface features of the area proposed for the pond or the farm is also equally important. :iting fish ponds near the farmer3s other agricultural or livestock farming activities makes it easier to integrate all the farming activities. undrainable ponds require 9ust . a pond of %"" m M . but for a big area proposed for farm construction with a number of ponds for different purposes and of different sizes. m of earth to construct around a dyke of ! m high above ground level =K.% m depth of cutting. however.* m. if possible. Although certain well-defined guidelines do e ist for the construction of fish ponds. ponds designed and constructed for fish culture are easier to manage and are e pected to give higher production. The labour and materials required for construction and operation should also be locally available as far as possible. because it may hold appreciable quantity of water with a small amount of earthwork.1 Topog!aphy 2t is economical and convenient to construct ponds in waterlogged areas. it is essential to conduct contour survey for determining the topography and land configuration.1. 2t also reduces the risk of poaching. From an efficient management point of view the pond site should. This limited depth of cutting reduces the construction cost considerably... ha> of water area requires only ) !)..1.freshwater areas in the tropics and are used for fish culture with minor improvements. certain basic principles to be considered when choosing a site and deciding the method of pond construction. ?owever. full consideration should also be given to the possible effects of flood.> with side slope ratio of !F% and top width of %. This quantity of earth may be obtained only from %. ) For smaller and flat areas eye estimation is enough. be within the sight of the farmer3s house. irrigation command areas or in marginal lands. unlike drainable ponds. For e ample.2 /ou!c o' %at ! and its "uality A dependable source of water supply must be available within or near the site.." m =". ?owever. stream. alternative arrangements of water supply should be made for dry season either from a deep tube well or irrigation canal or from perennial sources like spring.sufficient water to fill the ponds and to compensate the water loss through seepage and surface evaporation thereafter. The farmer will need huge quantity of lime to neutralize it while highly alkaline water may cause the precipitation of both phosphate and iron. also helps in maintaining water level in undrainable ponds =:ahoo. is most suitable for carps. ?owever. it collects nutrient salts from the ground surface of the catchment area. %7+. ?owever. #ater should be clear as far as possible. ranging between %*H. thus reducing primary productivity of the pond. 1979) Soil type -lay -lay loam :ilty loam :andy loam %'* *'%" %"'!" !"')" Infiltration rate (mm/ha) .>.. Table 5 Infiltration rates of different types of soil (Stern. #ater temperature also significantly influences the feeding and growth of fish. 8ain water does not carry any dissolved salts. Table * shows the filtration rate of different types of soils. The best soils for our purpose are thus the impermeable clay which can be easily compacted and made leak proof.in tropical areas. The chemical quality of water depends on its content of dissolved salts.and )*H. The water should be neither too acid nor too alkalineG neutral or slightly alkaline waters are most suitable for fish culture and hence acid water should be limed to make it neutral. it may be harmful to fish. :oils with a low infiltration rate are most suitable for fish pond. The water supply to the pond should as far as possible be natural. The quality of the available water is also equally important for fish culture.# /oil typ @ond soil must retain water. #aters with p values below *. etc.* are not proper for fish culture. @onds should be on the lower lands to allow accumulation of surface runoff from a larger catchment area. preferably rain water. @ond fish production is influenced by the physical and chemical properties of the water.1. Turbid waters which carry suspended solids cut the light penetration. in addition to absorption from rain water. A higher subsoil water table due to irrigation in surrounding fields and percolation from artificial or natural channels. and if it remains continuously above p 7. river.* or over +. ? ? . ?owever. @revailing water temperature. D cess of suspended solids also adhere closely to the gill filaments and cause breathing problems. care should be taken to provide proper bypass or spillway to avoid flooding. Dqually important is the need for avoiding e cess water and hence there must be arrangement for the e cess water to escape through a bypass channel or a spillway. . An arbitrary soil profile chart is presented =Fig.. although they tend to seal themselves with time. but if they are the only ones available they must be made impermeable with a thick coating of clay or with polythene sheeting. The layout of a complete farm is given in Figure %). the following additional points are also to be considered.oamy soils can also be used. the detailed designing and layout of the ponds1farm are done. while the organic matter decomposition may lead to dissolved o ygen deficiency. only nursery and rearing ponds are to be constructed with a small area for few stocking ponds to be used for raising the brood fish. Treated areas should be kept moist for !') days by gently sprinkling water to avoid cracking and finally the pond is filled with water =:ahoo. Accurate determination of the composition of the soil and its waterholding character is possible by hydrometer method.>.2 D signing <ased upon the survey on topography. :andy and gravelly soils should be avoided. :everal test holes may be made across the site and soil samples may be collected vertically from every ". @eat soils have special problems. To attain this size.. :oil impermeability can also be achieved by soil compaction at the pond bottom and dyke with either a mi ture of soil L %' *( cement or soil L %"'!"( cowdung. and may leak slightly in the early stages.1 Wat ! a! a !atio among pond typ s The production or stocking ponds are stocked with large size fingerlings of about %"'%* cm size in the case of composite fish culture. A general and convenient field test for the soil quality is to take a handful of moist soil from the test holes made at the proposed site and to compress it into a firm ball. since they are usually very acidic in nature and need sufficient liming. while in the case of fish production farm only stocking ponds are to be constructed for producing table size fish from fingerlings. soil type. :uch ponds would then have little plankton population and macrophytes and would be relatively sterile. m in a test hole. :oils rich in limestone also create special problems.. water supply. This can be overcome by adding sufficient organic matter such as cowdung.:and )"'%"" . a soil profile chart for the proposed site may be drawn. . 2f the ball does not crumble after a little handling.* m. etc. %!> showing the presence of clayey soil up to a depth of ). Asing the results of the soil tests.2. ?owever.* m of depth reaching up to a level of )'. 2n the nursery ponds the hatchlings are reared up to fry stage and in the rearing ponds the fry are reared till fingerling stage. pers. since the e cessive lime content tends to precipitate phosphate and iron. . rearing and stocking ponds in a fish farm depend upon the basic ob9ective of the farm. the hatchlings are reared in much smaller and shallower ponds called nursery and rearing ponds for about !') months.comm. it indicates that it contains sufficient clay for the purpose of pond construction. The ratio of water area among nursery. etc. poultry manure. 2n case of a fish seed farm. but they need well compacting. Figure %!.* to !. 8earing ponds are relatively larger."& to ". total water area of ".%" ha in size and %. For newly constructed undrainable ponds.!* to %."& ha water area and %'%. The sizes of stocking ponds vary tremendously. @onds having ". ?owever. nursery ponds should be small and shallow. :oil @rofile ." ha is recommended =Table &>.* m depth are most suitable as nurseries."!'".There is no hard and fast rule regarding the size of a pond." m in depth. preferably between ". Figure %). ;ayout of a Fish Farm =;and area ).& ha> 2n shallow ponds the water becomes heated easily. 2n deeper ponds light cannot reach the bottom. 2n very deep ponds thermal stratification may occur with colder deo ygenated bottom layer. 4ead plankton and faecal matter from fishes may fall on the bottom layer where the nutrients may be locked up. ?owever, in case of rain-fed areas where the water table goes down during the dry season, the depth should be kept around )." ' ).* m to store more water during the rainy season. Although a square pond is economical to construct for its minimum length of dyke, a rectangular shape of the pond =lengthFwidth in proportion of )F%> is considered to be ideal. 2n any case the pond width should not e ceed )" to ." m as it is difficult to operate a fishing net in broader ponds. The nursery and rearing ponds may be square, since they are too small to pose any problem for netting. The corners must be curved to avoid fish escaping the net during harvesting. The layout plans of nursery, rearing and stocking ponds are given in Figures %.A and %.<. Table & @ractical size and depth of nursery, rearing and stocking ponds =:ahoo, %7+.> D pth> 0m2 (ond typ /i= 0ha2 I!!igat d command5%at ! logg d a! as ,ursery pond 8earing pond "."! ' "."& %." ' %.* "."& ' ".%" %.* ' !." !." ' !.* Rain' d?5non:i!!igat d a! as %.* ' !." !." ' !.* !.* ' ).* :tocking pond ".!* ' %." N D cluding the freeboard L $ay vary depending on impermeable strata at pond bottom ..2.2 Dy6 The dyke should be properly designed so that it can hold ma imum water in the pond and withstand the hydraulic pressure. The slope of the dyke usually depends on the type of soil. :uitable side slopes for different soil types are given in Table 6. Figure %.a. 4esign of ,ursery, 8earing and :tocking @onds Figure %.b. -ross :ection 4etails of @onds Table 6 :uitable slopes for different soils =:ahoo, pers.comm.> /oil typ -lay -lay loam :andy loam :andy %F% to !F% %.*F% to !F% !F% to !.*F% )F% /oil 0ho!i=ontal7* !tical2 @rovision for a berm of sufficient width may also be provided for stabilizing the slopes. A wider berm also helps in operating the net in the pond. The berm should be % m or more in width =:aha and Kopalakrishnan, %76.>. The top width of the dyke should be decided taking into account its usage. Asually the minimum top width of the dyke should be %.* m. The wider crest requires not only a larger area for dykes, but also an increased amount of earth material involving heavy e penditure. 2t is always wise to design the dyke as per the #hile designing. . For swampy and waterlogged areas the most desirable time is the late summer when the area becomes completely dry.2 (! pa!ation o' sit The site should be thoroughly cleared of all the trees. :ome tree trunks rot very slowly and may cause problems during netting. 2n such cases deweeding is needed before filling the pond. .quantity of earth e pected to be available from e cavation work.# Const!uction <efore initiating the construction work."( clay is most suitable for dykes. :trings are stretched between the tops of pegs and posts to mark the complete profile of the dyke with its correct height. if a pond is built during winter or early summer and is not filled immediately. etc. %&>. . if e cavated soil quality is not up to the above standard. about %"'%!( allowance may be given for settling of earthwork =Fig. %*>.#. proper estimates have to be prepared based upon the design details. 2nitially. provision may be made for a clay core to make the dyke watertight. lines are drawn according to the layout. ?owever. .#. . followed by pegging and fi ing stakes or posts. A soil-type containing appro imately !*( silt. Figure %*... width and slopes =Fig.. weeds may grow and cover the bottom.o woody material should be left because the same will eventually rot and cause leaks.. bushes. Dven the roots of trees should be removed. The best time of the year for constructing ponds in clayey soil is post-rainy period and winter when the soil is soft rather than at the end of the dry season when it is very hard. :trict supervision is required at every step of construction to ensure the adherence to specifications laid down in the design.#. )*( sand and . 4esign of a 4yke with -ore #ell and /ey Trench . which will include the cost of all the materials and the labour. the work becomes easier and economical.1 Tim o' const!uction 2f the construction work is taken up at the most appropriate time or season of the year.# Ma!6ing th outlin s This operation involves laying out the features of ponds on the ground in order to mark out the areas from where the earth will have to be cut and removed and also where earth will have to be embanked. ?owever. compacted and deposited in %"'%* cm thick layers. .* m deep. The key trench is a small ditch or furrow dug along the line of the centre of the walls about ". the construction of a key trench becomes essential and in such cases digging should be done until watertight foundations are reached.. All dykes should be raised. ordinary soil should be well compacted into the trench.) (! : 4ca*ation %o!6 @rior to pond e cavation and dyke construction. This trench is filled in with a good clayey soil and is well rammed. a clay core is provided in the dyke to make it watertight =Fig. All large clods should be broken and each layer should be thoroughly consolidated by watering and ramming. The sides and top of the dykes should be properly dressed and finished with wooden thappies =wooden block with handle for ramming>. and in such cases each layer should not e ceed !" cm in thickness. This should be consolidated.#.#.* m ' %. gravelly or marshy soil base.. all loose surface soil should be removed from about !" cm depth within the total outlined area of the dyke and the surface should be roughened by ploughing or digging. #hen the dyke is to be made on a sandy. it is desirable to dig a small OEP shaped key trench =Fig.%*>. Dach layer should be adequately moistened before the ne t layer is laid and precaution should be taken to prevent the puddle from becoming dry and cracking. dumping the earth layer by layer stretching right across the whole section.%*>. The purpose of the trench is to stop seepage of water underneath the walls. (ond 4ca*ation and const!uction o' dy6 s The e cavation work can be carried out within the area marked for the pond bottom either manually or mechanically. A mi ture of %F! of sand and clay is used to make the clay puddle. .. the final levelling of the pond bottom and sides should be done manually with proper ramming and finishing as per the original design. ?owever.. The construction of the pond becomes economical if earthen dykes are made around the pond using the e cavated earth from the pond bed. 2n case the soil quality is not suitable for making dykes. 2f good clayey soil is not available in the area. 2n order to unite the body of the dyke to subsoil." m wide and ". Trees are not desirable since their dense shade inhibits the productivity of the pond. .Figure %&.ayout and @egging before @ond -onstruction =-orner Eiew> 4ykes must be well compacted to render them stable and the top should be rammed flat so that small vehicles can also run along when needed. . :hort creeping grass is recommended to be grown on the top and sides of the dyke. the intake should be securely wrapped by a firm net to prevent undesirable fish and other animals from entering into the pond along with the water. A sluice is also suitable for this purpose. in that case. The worst damage is done by common carp. The area should be levelled with more soil and thoroughly rammed and then grass should be planted to bind it. Drosion due to frequent wave action. . The grass turfing needs special attention. stakes1bamboo piling =Fig.#. A proper inlet enables the quantity of water flowing into the pond. can cause undercutting of banks and subsequent collapse of dykes. %6 <>. Attending to minor damages regularly avoids the chances of more costly repairs later. The feeder stream must therefore be diverted along the side of the pond and from a suitable point water is channeled to the pond when required. :ide erosion at the dyke bottom may be due to a number of reasons. %+>. a feeder stream running directly into the pond should be avoided. preventing the entry of undesirable fish and other aquatic animals and the escape of stocked fish.) Maint nanc @roper maintenance of the pond and pond structure is most essential. are susceptible to weathering action and hence they need periodical checks. To avoid scouring when the pond is being filled. A screen is also fi ed to check the entry of undesirable fishes and other animals =Fig. For small ponds the best inlet structure is a galvanized iron pipe of about %" cm diameter with a control tap and a screen basket =Fig. $ost of the earthen structures. The downstream end of the pipe should be )"'. particularly if the grass at the edge has been grazed by grass carp. 2f gravity feed is not possible.." cm above the water level. especially for larger ponds. a layer of gravel laid down.. if water is let in with a pipe there should be a gravel bed laid down where the water stream falls into the pond. water must be pumped from the supply source into the channel leading to the pond or even directly into the pondG but.. especially the dykes. or more cheaply. Wat ! inl t st!uctu! :ince we are concerned here with static and undrainable ponds. stone or brick pitching. %6 A>. . @roper and timely mowing prevents the formation of weedy growth and tends to develop a root system more resistant to runoff. :ome methods used to provide protection against such erosion are earth berms. An inlet structure should be provided through which water can be let into the pond. :imilarly. to be regulated. Drosion from the top during heavy rains causes grooving out of small channels and it is an indication that the top has not been properly consolidated. a concrete apron can be built at the sluice.. Figure %6A. Eiew of an 2nlet :tructure . :ome of the basic criteria for selection are discussed below.Figure %6<. only a restricted number of species are usually cultivated on commercial scale. 8easons for this restricted choice is obvious.. The undrainable ponds should therefore be dewatered in the summer months at the interval of *'6 years. . FI/H /(&CI&/ /UIT-9$& FOR CU$TUR& IN (OND/ Although a large number of fish species grow successfully in ponds. Additional 4etail :urface washings and organic additions cause siltation which reduces the pond depth and pond fertility. -ommercial pond culture basically aims at achieving ma imum possible rate of fish production and profit through optimum utilization of the natural food and the supplementary feed which drastically limits the choice of fish species for pond cultivation. 8. This has already been described under :ection . To find all these qualities in one fish species would be very unlikely. and common carp =-yprinus carpio> are cultured under polyculture system in ponds. non-predatory carps. 2n -hina. planktophagous and preferably herbivorous and detritus feeder -ompatability with other cultivable species of fish @alatable with high nutritive value ?igh market demand and high price. viz. 8. and the 2ndian composite fish culture system where the 2ndian ma9or carps and -hinese carps are combined. rohu =. . black carp =$ylopharyngodon piceus>. mud carp =-irrhinus molitorella>.2 Fish sp ci s suita3l 'o! cultu! in und!aina3l ponds There are two ma9or systems of carp culture in AsiaF the -hinese polyculture system where -hinese carps are cultured together. the species having ma imum required traits are considered to be desirable for cultivation in undrainable ponds. bighead carp =Aristichthysnobilis>. grass carp =-tenopharyngodon idella>. two -hinese carps. Therefore. three 2ndian carps. catla =-atla catla>. -arps fit well to these criteria and hence the most widely cultivated food fishes in :outh Asia are the quick-growing.on-predaceous. viz.8.1 C!it !ia 'o! s l ction o' suita3l 'ish sp ci s • • • • • • • • • • • Adaptability to undrainable pond environment Faster growth rate Dfficient utilizers of natural food resources of the pond Dfficient converter of artificial feed ?ardy and not easily susceptible to disease Dasy to breed and rear the seed @rolonged breeding period or multiple breeding frequency . and common carp =-yprinus carpio> are e tensively cultivated. silver carp =?ypophthalmichthys molitri > and grass carp =-tenopharyngodon idella>. -hinese carps such as silver carp =?ypophthalmichthys molitri >.abeo rohita> and mrigal =-irrhinus mrigala>. Ander the 2ndian system of composite fish culture in undrainable ponds. . phytoplankton and smaller molluscs. 8. . Ander composite fish culture in ponds it usually grows to over % kg in one year. 2t naturally breeds in rivers during monsoon season and under control conditions in bundhs as well. $alaysia and Thailand.anka. Anti-erosion $eaasures 8. ?owever. 0apan. it responds well to hypophysation techniques.1 Catla -atla is the fastest growing 2ndian ma9or carp species and widely distributed throughout 2ndia. Adult stages are predominantly zooplankton feeder. <angladesh and <urma =Fig. !">. . @akistan. .aos. 2t does not breed in ponds.2.2 Rohu 8ohu is the natural inhabitant of river systems of 2ndia. 2t inhabits the surface layer of water and feeds upon plankton. A::8. occasionally taking in decaying macrovegetation. %7>.ike catla it naturally breeds in rivers and under special conditions in bundhs. 2n recent years it has been transplanted to many countries of the world including :ri . 2t attains maturity in the second year of life and carry over 6" """ eggs per kg body weight =0hingran.ormally it occupies the column region of the aquatic ecosystem and feeds mostly on vegetable matter including higher plants. :eeds are easily reared in undrainable ponds of relatively smaller size. $auritius. . . @hilippines.Figure %+. %7&&>. D cept by hypophysation to which it responds .2. detritus.epal. etc. <urma and <angladesh =Fig. @akistan.epal. decayed vegetable. <angladesh and <urma =Fig.# M!igal $rigal inhabits all the ma9or river systems of 2ndia. Fecundity varies from !!& """ to about ! +"" """ depending upon the size =/han and 0hingran. Ander pond culture conditions it grows to over % kg in one year. -atla =-atla catla> . it never breeds in ponds. 2t is basically a bottom feeder and hence suitable for cultivation with column and surface feeder carps in ponds. 8ohu spawns during the monsoon =AprilQ:eptember>. """ to over % 7"" """ depending upon size. pieces of higher plants. 2t attains se ual maturity during the second year. %76*>. The adult fish feeds upon filamentous green algae. @akistan. certain percentages of pond-reared specimens mature within one year. ?owever. 8. :eeds collected from rivers or produced by bundh breeding or induced breeding are reared with ease in seasonal or perennial undrainable ponds.2. diatoms. Ander pond culture conditions it grows upto 7"" g within one year. 8earing of seed is usually undertaken in seasonal or perennial undrainable ponds. but can be easily bred in bundhs and by hypophysation.quickly. Fecundity ranges between %!. 2t does not breed in ponds. 2t is now being induced to breed twice within the same spawning season. $rigal usually attains maturity within % or ! years depending upon the agroclimatic conditions of the location. !%>. mud and detritus. Figure %7. :pawning season is linked with the onset and duration of the southwest monsoon. % of this manual>.abeo rohita> Figure !%. 2t readily accepts supplementary feed like oil cakes and rice bran mi ture in pond culture systems. whereas in 2ndia it matures very early. %7&)>. :ukumaran and @arameswaran. 2n composite fish culture ponds it usually attains over %. 2t is a surface dweller feeding mainly upon zooplankton during its early stages and gradually becomes predominantly a phytoplankton feeder. within ! years. through the technique of hypophysation they are induced to breed in ponds during the monsoon season =:ection +. ?owever..* """ to ! ". 8ohu =. $rigal =-irrhinus mriqala> 8.Figure !".2. 2ts relatively longer branchiospines provide a fine filter capable of retaining planktonic organisms. $ales mature earlier than the females.* kg within one year of . 2t does not breed in pond condition. 2t takes about !'& years to mature in -hina. """ has been found from silver carp =Alikunhi.) /il* ! ca!p :ilver carp is basically inhabitant of ma9or river systems of :outh and -entral -hina and in the Amur <asin of A::8 from where it has been transplanted throughout the 2ndo-@acific region including 2ndia. A fecundity range of %. Fecundity varies greatly with the size and agroclimatic condition. orth -hina. etc. weeds. Asually it grows to over %.2. . They are voracious eaters and show distinct preference for vegetable food materials such as grass. :eed rearing is done in smaller seasonal or perennial undrainable ponds with a high rate of survival =Fig. becomes choice food for the bottom dweller common carp =Alikunhi. 2n -hina it takes about )'. years to achieve maturity whereas in 2ndia it usually takes ! years. and the Amur river of A::8. 2ts suitability in aquaculture and biological control of aquatic weed infestation has resulted in wide-scale transplantation throughout the world.* kg in composite fish culture ponds =Fig.rearing. The total number of eggs range between )"+ +"" and &%+ %"" from the fishes weighing between . ?owever. Asually only a portion of ingested food is digested and the rest is voided in semidigested or undigested form which. %7&)>. they also accept supplementary artificial feed materials. !)>. Krowth mainly depends on the rate of feeding. !!>. The fish does not breed under pond condition and hence seed production is achieved through hypophysation. in turn. %76*>.." kg. Ander optimum feeding rate it can grow over * kg in one year =:inha and Kupta. :ilver -arp =?ypophthalmichthys molitri > 8.. +!ass ca!p Krass carp is a native of the river systems of :outh--entral and . leaves. :ukumaran and @arameswaran. Figure !!.6 kg to 6. 2n early life it feeds on planktonic organisms and gradually switches over to macrophytes. Common ca!p 5riginally a native of temperate region of Asia. 2n a tropical climate it spawns throughout the year in the pond environment with two peak periods.2. 2n tropical conditions it attains maturity within %! months =Alikunhi. This habit of digging the pond bottom helps in maintaining the productivity of undrainable ponds and hence culture of common carp with other carp species is of great advantage. the common carp is now the most domesticated and cultivated carp species throughout the world =Fig. 2t frequently burrows the pond bottom in search of food. Krowth mainly depends upon the bottom biota.Figure !) .. stocking density and the rate of supplementary feed. . Krass carp =-tenopharyngodon idella> 8.!. Dggs are small and adhesive in nature. %7&&>. especially -hina. $oreover. 2n composite fish culture ponds it grows to about % kg within one year. one from 0anuary to $arch and the other during 0uly and August.>. 2t is an omnivorous bottom dweller subsisting mainly on benthic fauna and decaying vegetable matter. it also feeds directly on the undigested e creta of grass carp. a farm should be self-sufficient with nursery and rearing ponds so that after meeting their own demand the surplus seed can be sold for additional farm income. (ROCUR&M&NT OF IN(UT/ :eed. 5nly some feed additives are needed to be procured from towns. mrigal.Figure !.1 (!ocu! m nt o' s d D cept common carp. construction of large. ?owever. Animal manures are incidental to village-based allied agricultural and animal husbandry activities while fertilizers are readily available in the local markets throughout the year. This is mainly due to the large-scale development of this farming system creating ever-increasing pressure on carp seed industry. -ommon carp =-yprinus carpio> @.. The successful development of the technique of induced breeding through hypophysation ensures breeding of both 2ndian and -hinese ma9or carps in . rohu. all the other five 2ndian and -hinese ma9or carps. catla.and small-scale carp hatcheries has provided enough support to this industry during recent years. cultivated under composite fish culture do not breed in pond conditions although they attain full gonadal maturity. undrainable village ponds are most suitable for this purpose. @rocurement of feed is not a problem as most of the feed materials are village-based agro-industrial products and by-products and are readily available in villages and local markets. seasonal. viz. 2deally. they breed in bundh type tanks. :mall. feed and fertilizers are the three ma9or inputs of undrainable pond culture systems. ?owever. @aucity of quality fish seed is even now considered as one of the ma9or constraints in the development of freshwater carp farming. silver carp and grass carp. @. when the 2ndian ma9or carps normally breed. @. Therefore the stocking materials are procured from three different sources.* to ).1. The posterior end has a small round opening fi ed on a bamboo ring. collection by traditional methods from rivers.1. 8iver margins with gradual slopes are the most suitable sites. monsoon flooding patterns.1. @. !*a and !*b>. The net is fi ed in marginal waters where depth of water is negotiable without any aid. suitable nets.1 /pa%n n t and its op !ations These are funnel-shaped nets made of fine mesh =%.captivity. availability of sufficient brood stock and the success of spawning.1 Coll ction o' spa%n '!om !i* !in sou!c s The technique of spawn collection from rivers essentially consists of operating fi ed filtration nets in marginal areas of flooded rivers during monsoon months. #ater flow in the range of !" to &" cm1sec is desirable. viz. by induced breeding of carps and by breeding in bundh-type tanks. :uccess of operations mainly depends on proper sites. -ollection of 8iverine :pawn . A small trough-like receptacle =gamcha> is tied to the ring where live spawn is collected. Figure !*a." mm> handloom nettings =Figs. . . 8iverine :pawn -ollecting .1. the nets should be removed.. At every four hours. along with their confluence with the main river as these may be connected with the breeding grounds. streams.. $easurement of spawn should be done by special sieve cups =Fig. The distribution and composition of the fish fauna in the selected stretch of the river for assessing the resident population of 2ndian ma9or carps.1. Asually early spawn measures about *"" individuals1ml. cleaned and refi ed.1.!&>. . The nets should be fi ed along the river margins with the help of bamboo poles and are ad9usted according to changes in flood level.# Coll ction op !ation To assess the availability of spawn. . . *. and the spawn should be conditioned in hapas =cloth compartments fi ed in water> before they are transported. The flowing spawn are collected in the receptacle =gamcha> from where they are scooped every %* to )" minutes. should be scooped from the receptacle =gamcha> and transferred to aluminium containers =hundies> half filled with water.1. :pawn availability is mostly associated with receding phases of floods.2 /it s l ction A premonsoon survey should be conducted to collect the following details. initially !') spawn nets should be operated constantly at suitable sites and the whole battery of nets should then be introduced as soon as the spawn become available. %. !. debris. etc. Topography of dry beds and bank features to know the likely current pattern of the river at different levels of flooding. The accessibility of the site. minor carps. The seed collected from rivers are generally a mi ture of seeds of ma9or carps. ). etc. depending on the amount of spawn being collected. @. predatory fishes.et @.ocation of tributaries. The collection should then be sieved through round meshed mosquito netting to segregate spawn from debris and larger fishes. The collected spawn along with the bigger fishes. based upon which the suitable site is selected.Figure !*b. etc. The topography and terrain and river bank features in the vicinity of a site to determine the e tent of area available for operating nets at different flood levels. . . !6A and !6 A-%. !6< and !6 <-%>. %7. but a bundh could be as large as )"" ha. @.1. The wet bundh contains a deeper area which retains water throughout the year and where adequate stocks of brood fishes are maintained.> =Figs. The wet bundh varies in shape and size from place to place. The bundhs are ordinarily of two categories. the ponds covering a water body of %'! ha with catchment area ranging from !"'%"" times are considered as wet bundhs. if any. :ieve -up for $easurement of :pawn1Fry @..2 9undh 3! ding <undhs are special types of perennial and seasonal tanks or impoundments where riverine conditions are simulated during monsoon months. is drained through the outlet which is guarded by bamboo fencing =locally termed as O-hheraP>.2. a ma9or portion of the bundh is submerged and e cess water. viz. 4uring heavy rains. Kenerally..Figure !&.1. The shallow areas of the bundh =moans> serve as breeding ground for fishes present in the bundh. a perennial bundh commonly known as O#et bundhP and a seasonal one called O4ry bundhP =$ookher9ee et al.1 W t 3undh A typical O$idnapore typeP of wet bundh is generally located in a gradual slope of a catchment area with an inlet towards the high land and an outlet at the opposite side towards the lower end to regulate the inflow and outflow of water respectively during heavy showers. <undh for <reeding =#et Type> .Figure !6A. Figure !6A-%. <undh for <reeding =#et Type> . 2 D!y 3undhs This type of dry bundh consists of only one shallow depression =or one shallow pond> and a catchment area located in a gradual slope. <undhs for <reeding =4ry Type> Figure !6<-%. The upper high land area is considered as a catchment area.Figure !6<.1. <undhs for <reeding =4ry Type> @.2. The shallow depression or pond is enclosed by embankments on three . # 9! ding op !ation W t 3undh7 #ith the onset of monsoon the fresh rain water from the catchment area enters into the bundh and the latter is inundated. some fresh water is released from the reservoir into the breeding bundh. the brood fishes from a perennial pond are introduced into the seasonal ponds to breed. %76). The spawners are allowed to remain for %"'%! hours in order to get acclimatised to the environment.% to ". %76). 4ry bundhs of $adhya @radesh are comparatively bigger in size =". The reservoir and breeding bundhs are arranged in a sequence along the gradient so as to facilitate the flow of water which is controlled through a system of sluice gates. A deeper tench is dug along the lower e tremity of the breeding bundh so that the breeders can take shelter before and after spawning. The outlet is guarded by fine bamboo fencing.* ha>. which are cloth compartments fi ed in water with the help of poles at its four corners =$oitra and :arkar. %7*6>. After administration of the second dose of e tract to the females..2. :pawning usually commence during and after heavy showers when the bundh as well as the catchment area are flooded with fresh rainwater. %76*>. 2n the #est <engal @rovince of 2ndia. @remonsoon rain water is collected from the catchment area to fill up the reservoir. preferably on cool rainy days. %76*>.'* hours.sides which impounds freshwater from the catchment area during the monsoon season. %7&%>. the second dose =+ mg1kg> of e tract is in9ected to the female. The selected female breeders are taken out of the hapas and in9ected intramuscularly with fresh pituitary e tract. The breeders present in the deeper area of the bundh migrate to shallow areas where they start breeding. The upper one where the premonsoon rain water is collected from upland catchment area serves as a OreservoirP and the lower one is used for breeding purposes. After . Kenerally. Thereafter. 2n a modified bundh. :uch bundhs remain more or less dry during the greater part of the year.! to !. The water-holding capacity of the reservoir is generally more than that of the breeding ground bundh. The e cess water flows out from the bundh creating a water current. The females are administered an initial dose of the e tract at the rate of ) mg1kg body weight and thereafter kept again in mosquito net hapas. ad9acent ponds are constructed along the gradient of the catchment area =$oitra and :arkar. a catchment area more than five times the size of the bundh is considered most suitable =:aha et al. @. A few sets of males and females are then selected and taken out from the bundh and placed in separated mosquito net hapas. There should be provision for an outflow for drawing e cess water from the pond during heavy rains.* ha> than those of #est <engal =". but sometimes this proportion is not strictly followed. At the same time the males are given the initial dose of the e tract at the rate of ) mg1 kg of body weight. 2n a modified method adopted in <ankura and $idnapore districts of #est <engal. Kravid carps from the perennial ponds are then transferred to the breeding bundh.1. the inlets and outlets of the bundh are lifted to allow the entry of a steady flow of water from the reservoir into the breeding bundh soon after breeding . D!y 3undh7 8ain water which accumulates in the catchment area during premonsoon showers flows in to fill up the pond seasonally. the ratio of male and female spawners is maintained at %F%. whereas in $adhya @radesh the recommended ratio is %F!* =4ubay and Tuli. The in9ected spawners are then released into the breeding bundh. 2n one such bundh *'& breeding operations can be taken up in one season. sub9ect to availability of spawners and fresh water. This is due to the fact that the pituitary gonadotropic hormones which induce spawning are not released in sufficient quantities from the pituitary gland =hypophysis> to the general blood circulation so as to trigger spawning. :pawn are usually sold at the bundh site. although they attain maturity. To collect eggs.1. (ituita!y gland o' maAo! ca!ps and its coll ction7 The pituitary gland or hypophysis of Asiatic ma9or carps is a small.. As discussed earlier. for induced spawning.. 2n such areas a series of earthen pits are constructed with water flow facilities. pear-shaped. silver carp and grass carp were also bred in %7&! =Alikunhi et al. under pond culture conditions.takes place. %7&)>. situated on the ventral side of the brain below hypothalamus. whitish soft body. :ubsequently. D otic carps such as grass carp and silver carp have also been induced to breed in the dry bundhs of #est <engal by applying pituitary e tract and under regulated water flow =:inha et al.e. %76+>. The quantum of gonadotrophic hormones in the pituitary vary with the season and maturation stages of the fish and hence the degree of success achieved in induced spawning depends very much upon the condition of the pituitary gland of donor fish. the water level of the bundh should be lowered by opening the outlet. Therefore. the hypophyseal hormones e tracted from the pituitary of donor fish are in9ected into the se ually matured fish under favourable water and climatic conditions during the monsoon season. @. <ased on a series of e perimental trials it has been found that the ma imum success in induced spawning is possible with e tracts prepared from gland collected during $ay10une. The gonadotropic hormones secreted by the pituitary gland of fish play an important role in the process of maturation and spawning. the period 9ust before spawning =$oitra and :arkar. Coll ction o' ggs7 Dgg collection is taken as soon as the embryo starts twitching movements. #ell preserved iced fish are also . the water is completely drained out and it is allowed to dry. This outstanding success in induced spawning of Asiatic ma9or carps has revolutionized carp culture practice through commercialization of carp seed production. <efore starting the ne t breeding operation in the same bundh. which is connected to the pituitary gland by a funnelshaped structure. the infundibulum. use of hormones for inducing spawning in 2ndian ma9or carps has been in practice for the last three decades. Thus the pituitary glands for the induced spawning programme should preferably be collected from the freshly killed fully matured specimen of both the se es of the same =homoplastic> or allied species =heteroplastic> during $ay10une when the potency of the gland remains at its peak. %76*>. 2n 2ndia.# Induc d spa%ning 3y hypophysation As an alternative method. the first success of induced spawning by hypophysation of 2ndian ma9or carps was achieved by -haudhuri and Alikunhi =%7*6>. i. Dggs are generally netted by a piece of thin cotton cloth =gamcha> or a piece of mosquito netting cloth. Fertilized eggs are allowed to hatch in these pits and the spawn are collected after three days. the carps do not spawn. a perennial breeder. -ommon carp. has been found to be an e cellent donor fish as the potency of the gland remains more or less high throughout the year. Figure !+. in fish markets where a large number of fish heads are sold separately and the consumers strongly dislike dissected fish heads for consumption.1.#. D cess of watery fluid and the blood is soaked by absorbant cotton and then the membrane covering the gland is cautiously removed by using a needle and a pair of forceps.#. -ollection of @ituitary Kland @. The gland thus e posed is picked up very carefully avoiding any damage =Fig. <oth male and female donor fish are suitable for gland collection. @. the glands are taken out from behind the head through the foramen magnum.suitable for this purpose. it is .1. <ut when we need a large number of glands to take up breeding on a commercial scale. !+>. 2n 2ndia. The brain thus e posed is lifted up by detaching the optic nerve. The technique of removing glands by this method is simple and quick.1 Coll ction o' gland The commonly adopted method of gland removal is by chopping off the skull with a sharp butcher3s knife or a hand saw. The brain tissues are removed through this foramen magnum and then by close e amination the gland is located embedded in the floor from where it is scooped out carefully with the help of a small scooper. <ehind the head there is a big hole in the brain case known as the foramen magnum.2 (! s !*ation and sto!ag o' glands Freshly collected glands have been found to be the best for the induced breeding purpose. <roken or damaged glands lose their potency due to hormonal drainage. The advantage of e tract preservation is that the preserved material remains in the ready-to-use form which is very convenient. is then added.* ha with minimum water depth of about %. better results have been achieved from glands preserved in acetone. ?owever. etc. Thus the ratio of distilled water to glycerine is maintained at %F!. the age and weight of the donor fish. The phials are then kept at room temperature or in a refrigerator.1. 2mmediately after collection the glands are kept in fresh acetone and placed in a refrigerator. twice the volume of the distilled water. 2n such cases it is always desirable to ascertain the potency of such e tract through several breeding trials before initiating a large-scale breeding programme. tissue homogenizer. and are then weighed accurately. The stocking density should be kept at a relatively lower level ranging between % *"" ' ! """ kg1ha. @repared e tracts can either be ampouled in ampoules of various capacities or may be kept in small phials in a refrigerator. :uccess of hypophysation also depends on the condition of the spawner and hence proper attention must be paid to raise quality brood stock in adequate numbers. especially in villages where most of the basic facilities like precision balance." mg of gland for every ml of media. removal of predatory and weed fishes. @. the most popular being the preservation in absolute alcohol and after an interval of !. distilled water. Fresh glands are frozen immediately after collection and kept in a refrigerator.* m.1. pond . weighed and transferred to dark coloured phials containing fresh absolute alcohol.! to ". Alcohol dehydrates and defattens the glands. etc.#. The glands can also be kept frozen. A known quantity of glands is taken and macerated in a tissue homogenizer. :uch e tracts should be consumed within one breeding season.# (! s !*ation o' pituita!y 4t!act @ituitary e tract is normally prepared 9ust before administration as such e tracts cannot be kept long.#.not always possible to sacrifice so many matured fish for the required quantity of glands. Fish pituitary e tract is prepared in distilled water-glycerine media at a concentration of . 4etails about the place and date of collection. centrifuge.. There are several methods under use for the preservation of pituitary glands. there are certain simple methods for the effective preservation of pituitary e tracts. deep freezer or in insulated cans containing dry ice. @ure glycerine. hours they are dried. @.. @referably !') years old healthy male and female carps should be selected and reared in well prepared ponds of ". e traction from a large number of glands also ensures uniform hormone potency per unit volume of e tract. 4istilled water equal to one-third of the total volume of e tract is added to the fully macerated glands and thoroughly mi ed. #hen needed the stored glands are put on filter paper which allows the alcohol to evaporate. ?owever. After two days the glands are taken out. for e tract preparation are not available. <esides. :uch phials are labelled and placed in a refrigerator until use. :uch limitations dictate large-scale collection and preservation of glands from fish markets. weighed and replaced in phials with fresh aceton.ormal pond management schedules are to be followed strictly involving weed clearance. .) 9!ood stoc6 maint nanc and th i! s l ction 'o! spa%ning The two ma9or inputs of induced breeding programmes through hypophysation are the pituitary glands and the properly matured spawners. should be labelled on the phials for ready reference. The entire suspension is again thoroughly mi ed and filtered through filter paper to remove tissue fragments if any. Induc d 3! ding op !ation After the selection of brood fish the in9ectable dosage of pituitary e tract is calculated in terms of milligram of pituitary gland per kg body weight of the recipient fish. 2n some places the monsoon is early and hence the breeding season starts from April onwards.. $atured females have a soft bulging abdomen with slightly swollen and reddish vent. :upplementary feed consisting of %F% oil cake and bran mi ture should be applied daily at the rate of %')( body weight on underwater feeding plates. gonadal maturity of the recipients and the prevailing climatic conditions. The southwest monsoon period is the normal breeding season for these Asiatic carps in south Asian countries and usually e tends from April to :eptember.. or green animal fodder such as napier grass.fertilization and application of supplementary feed. .*" kg of silver carp and grass carp> comprising both males and females in a ratio of %F% by weight and !F% by number are required. -ool rainy days when the water temperature ranges between !*H. 2t is estimated that for a target production of about %" million spawn =& million of 2ndian ma9or carps and .'* months. etc. their individual weights are recorded using hand nets and a spring balance and the females are kept ready for the first in9ection of the pituitary gland. This rearing period normally lasts for . Asually after the onset of the monsoon when there is an accumulation of fresh rain water in the pond and a fall in atmospheric temperature. hybrid napier. Aniform size eggs of pale blue colour in silver carp and brown or copper colour in grass carp indicate proper maturation stage. million of silver carp and grass carp> about 6*" kg of brood stock =)"" kg of 2ndian ma9or carps and . The males are given only one in9ection at the rate of !'. duck weeds. The addition of %*'!"( fish meal.are considered to be ideal for induced breeding. mg1kg and *'%" mg1kg body weight respectively. the breeding programme is taken up. <y seining the pond. The first and second dose in the case of females of 2ndian ma9or carps may be given at the rate of !'. aquatic weeds such as ?ydrilla. barseem. They are also characterized by the roughness of their pectoral fins. fish health care and monitoring of pond environment. @. <y inserting the catheter in the genital opening of a female spawner.#. Females are given two in9ections at an interval of . if the abdomen is slightly pressed near the vent. 4etails about pond management are given in subsequent sections of this manual. some eggs are taken out and e amined at the pond site in a petridish. vitamin and mineral mi ture to the conventional feed gives better results.1.'& hours while males are given only one in9ection at the time of the second in9ection to the females. @roper care during this period ensures availability of well matured quality spawners for induced breeding programmes. spawners are caught and carefully e amined for selection.to )"H. The fish should be periodically netted and e amined carefully to find out the stage of maturity and state of health. 2t has been e perienced that a lower dosage is effective when e tract is prepared from fresh glands while a higher dosage is required when commercially supplied glands are used for the purpose. etc. For grass carp. A catheter is found to be quite helpful especially in the case of silver carp and grass carp in selecting the matured female breeders by e amining the condition of the eggs. mg1kg body weight at the time of the second . -onsiderable variations are noticed in the effective dosage of pituitary e tract which depends mostly on the potency of the pituitary gland.. $atured males ooze a milky fluid =milt>. are to be provided at the rate of !"'!*( of their body weight on a daily basis. 8ipe and healthy males and females of desired species are selected from the brood stock ponds.a9as. Dach set should consist of both female and male spawners in the ratio of %F! and appro imately %F% in weight. etc. through which spawners are introduced and taken out =Fig. blotted.. lakes." mg of pituitary gland. ?owever. canals. or plastic pools with continuous supply of water having controlled temperature ensure greater efficiency and operational ease." m> closed from all sides e cept an opening on one side with tying arrangements. A breeding hapa is a rectangular cloth container =!. <oth ready-to-use bottled or ampouled e tract or freshly prepared e tract can be used. dried and weighed accurately. The e tract is thereafter centrifuged to get rid of tissue fragments and only the supernatant solution is utilized for the in9ection. The glands are then macerated in a tissue homogenizer with a small quantity of distilled water and further diluted so that each ml of the e tract should be eqivalent to !"'. cement. $ales receive only one in9ection at the rate of )'. These hapas should be fi ed in the shallow waters of ponds. . $odern facilities such as breeding tanks of metal. For the preparation of fresh e tract the required quantity of glands should be taken out. as stated the dose of the pituitary may be slightly increased or decreased depending on the local climatic conditions.* %. fibre glass. mg1kg body weight. After deciding on the dosage. The spawners should be grouped into several sets. and reservoirs with the help of bamboo poles in such a way that twothirds of it are submerged in the water. The required number of breeding hapas at the rate of one hapa for each set should be fi ed in the pond.!7>. potency of the gland and the response of the spawners. :ilver carp and grass carp females should be given at the rate of )'. the quantity of glands required for in9ecting the selected brood fish is calculated.* %. mg1kg body weight during the initial in9ection and +'%" mg1kg body weight during the final in9ection.in9ection to the females. h. can be used for small size spawners. 2n the case of mrigal it is desirable to keep this interval of only . and released back in the breeding hapa.o. After the first in9ection to the female spawners. the needle is inserted under the scale initially parallel to the body of the fish and finally pierced into the muscle at an angle of .%7 for larger ones.""'%6. 2ntramuscular in9ections are commonly given in the caudal peduncle region avoiding the lateral line. For intramuscular in9ection. Table + . The <?4 needle . Figure )".'& h of the first in9ection i. )">. 2t is always convenient to apply the first in9ection between %&. 2n the case of intraperitoneal in9ection the needle is pushed with ease at the innerside base of the pectoral fins. in9ected as per prescribed doses =Table +>.!. . At the time of the second in9ection both males and females of the set are taken out.o. The size of the needle for the purpose is also important which depends on the size of spawner to be in9ected. both males and females of the set are released in the breeding hapa or the breeding enclosure. 2n9ecting a 4ose of <reeding ?ormone The induced breeding work is generally taken up on cool and cloudy days when the water temperature is around !*')"H-.*H =Fig."" hours and the second in9ection after .!! is conveniently used for %') kg of carp breeders and . The most convenient hypodermic syringe used for the purpose is of ! ml capacity having !" divisions.o.eedle . <reeeding ?apas in a @ond 2ntramuscular or intraperitoneal in9ections are administered. between !"' !) hours.Figure !7.e. The usual quantity of eggs obtained from 2ndian and -hinese ma9or carps under field conditions are presented in Table 7. !". the dry method of stripping is adopted where the spawners are wiped with a towel and then the female spawners are stripped and the eggs are collected in dry enamel basins and immediately fertilized with stripped milt from the male spawners. times with water. if the eggs are seen oozing out. 8ecent investigation of :inha =%76!>.Krass carpG :. 2t has been observed that in silver carp males the quantity of milt is insufficient and hence e tra males should also be in9ected to ensure ma imum fertilization of stripped eggs."" *'%" )'. A )( increase in body weight of female spawners between the two subsequent in9ections indicates better breeding success. the fish is considered to be ready for stripping. The eggs are released by the females in the early morning hours and are fertilized naturally inside the hapa by the milt released by males. )'. /eeping the ventral side up and by giving a slight pressure at the genital opening.:ilver carp <reeding normally takes place within )'& h after the second in9ection. The fertilized eggs are then kept in breeding hapas for a few minutes for proper swelling and hardening.4oses =mg of pituitary e tract1kg body weight of spawners> and in9ection achedules for hypophysation Tim o' InA ction inA ction 0h2 %st !nd F mal IMC spa%n !s> +C5/C Mal spa%n !s> +C5/C IMC !'. 5therwise they are released back and e amined again after an interval of %1! ' % h. Table 7 Ruantity of eggs obtained from cultivated carp species /p ci s o' ca!p -atla -pp!o4imat num3 ! o' ggs56g 3ody % ight %!* """ ' !"" """ . :ilver carp and grass carp normally do not release eggs inside a hapa or a breeding enclosure even after being in9ected with hormone and hence these fishes have to be stripped and fertilized artificially.* ' *. The females are e amined )'."" !'....2ndian ma9or carpG K. and thus serving as an indicator for the success or failure of the breeding programme. Asually. Konadotropins induce the hydration process thereby increasing the body weight of the spawners.""'!).* mm in diameter. Fertilized and viable eggs are transparent in colour while dead ones appear opaque under naked eye. The brood fishes are removed from the hapas and the eggs which are non-adhesive and semibuoyant swell like small pearls of ). has indicated that gonadal hydration is a prerequisite for successful spawning of carps. @ercentage of fertilization is scored from several egg samples e amined in a petridish or watch glass. h after the second in9ection to see their readiness for stripping. At this stage the eggs and milt are mi ed thoroughly for %'! minutes with the help of a clean feather and subsequently the eggs are washed )'. +'%" N 2$.""'%6. %&. The total quantity of good eggs laid is estimated from the total volume of eggs and percentage of fertilization. From the plastic buckets eggs are collected with the help of a % litre mug and spread uniformly at the rate of )'.1. ?atching hapa 5uter 2nner %.#. Incu3ation o' ggs and hatching The eggs are measured by a graduated enamel or plastic mug of %'! litre capacity and collected in plastic buckets.!* %.* %. The number of eggs to be spread in each hapa depends on the size of the eggs of the species concerned." ". Table %% Ruantity of eggs of cultivated carp species to be incubated in each hapa . litres of eggs in double-walled hatching hapas fi ed in ponds free from algal bloom.+ %." ".. 8ound mosquito netting of cotton1nylon cloth. The dimension of various hapas are given in Table %".+ %. Thick cotton1nylon cloth. Table %" 4imension of breeding and hatching hapas Typ o' hapa <reeding hapa Dim nsion 0m2 /p ci'ications $ ngth Width D pth !. The following table will be helpful in deciding the amount of eggs to be incubated in a hapa.8ohu $rigal :ilver carp Krass carp -ommon carp !*" """ ' )"" """ %*" """ ' !"" """ %"" """ ' %*" """ Around %"" """ %*" """ ' !*" """ @. Thick meshed nylon1cotton cloth.* %. and predatory fish species =Table %%>. The outer hapa is made of thick cloth or very fine meshed nylon cloth while the inner one is made of round meshed mosquito netting cotton1nylon cloth." closed from all sides e cept at the opening with tying arrangement.* Apper side completely open. Apper side completely open. These double-walled hapas are open from the upper side. At lower temperature the hatching time is considerably larger.1. several drawbacks and large-scale mortality and loss of developing eggs and hatchlings may occur due to natural hazards such as a sudden rise of water temperature. The hatchlings pass out through the mesh of the inner mosquito netting hapa to the outer hapa. 2t normally takes %!'%* h for the developing eggs to hatch out in 2ndian conditions. the inner hapa with egg shells is removed and the hatchlings are left undisturbed in the outer hapa for three days till the yolk sac is completely absorbed and the spawn become ready for stocking in nursery ponds. etc. %7+*>.ormally the rate of flow of water is kept at &""'+"" ml1min for 2ndian ma9or carps and +"" ' % """ ml1min for -hinese carps. 2n each 9ar of &. #ith a view to improving the hatching technique and reducing mortality of hatchlings.. :treptomycin . :arkar and :ingh. @. presence of predatory crustaceans. #ater hardened eggs are incubated in vertical hatching 9ars where the flow of water is so regulated during the incubation that the eggs are gently stirred without being spilled over." . o' ggs51 0-pp!o4.. :pawn are collected through drainage outlet. -ommon carp and other unwanted fish when present in the pond have been reported to cause severe damage to carp eggs in breeding hapas =Tripathi.)* % capacity. 6"" """ to % !"" """ fertilized eggs can be used per cubic meter of water. <efore releasing them back in the pond they should be given prophylactic antibiotic treatment. The use of %1." ). The hatching technique described above has./p ci s -atla 8ohu $rigal :ilver carp Krass carp No. . development of algal bloom. #hen hatching is completed.." -mount o' ggs in 15hapa ?atching time is temperature dependent. Asually hathing takes about %*'%+ h at temperature range of !&')%Hc. 2t requires a large volume of water with sufficient pressure to create a circular water current in the hatching cistern. however. -hinese hatchery system consisting of cisterns with diagonally pointed nozzles as water inlets and outlet with filtering screen and valve are also becoming popular.#.2 !! """ ' !* """ !+ """ ' )" """ !& """ ' )" """ !! """ ' !* """ !! """ ' !* """ .8 (ost:spa%ning ca! o' 3!ood 'ish 2t should always be remembered that spent carps are potential breeders for the ne t breeding season and hence they should be saved and properly cared for. *" """ eggs can be kept for hatching. Earious modifications of this hatchery system are now available and e tensively used. inch mesh size drag net as a barrier to prevent common carp from destroying fertilized eggs in breeding1hatching hapas may be a suitable way to solve the problem of those fish farmers who have only one pond and utilize it for composite fish culture =8adheyshyam. a glass 9ar hatchery has been designed by the -entral 2nland Fisheries 8esearch 2nstitute =-2F82> and found to be very useful in terms of percentage survival of hatchlings. depletion of dissolved o ygen. %76*>." ." ). the survival of spawn is always poor and hence they should be induced to breed under controlled conditions as per the following successive steps. :pawned breeders are then taken out and given prophylactic antibiotic treatment and released back to the pond. are also introduced in the hapa and uniformly spread.sulphate and penicillin at the rate of !* mg1kg fish and !" """ 2. Although they breed naturally in the ponds. Although they breed several times during the year. :egregated brood fish should be fed daily at the rate of )( of their body weight. ?owever.1. The females deposit sticky eggs on leafy vegetation in the pond which are immediately fertilized by the males. Asiatic ma9or carps breed only once a year.). @.1kg fish respectively in the form of in9ection has been found to be very effective in preventing post spawning bacterial infections and subsequent mortality. breeding should be taken up during mid0anuary to $arch and again during 0uly-August. <reeding hapas should be fi ed in the shallower region of the pond with the support of bamboo poles. The interval between the two breeding operations may vary from )" to &" days. They are induced to breed in the early part of the season. @. Multipl 3! dingF Ander natural conditions. in recent years it has been possible to breed them twice in a year. A set of spawners consisting of one female and two smaller males more or less equal to the weight of the female are released in each breeding hapa. Dichhornia =water hyacinth>. both the males and females can be released after giving the similar prophylactic treatment.) (!oduction o' common ca!p s d -ommon carp is the only fish cultivated under composite fish culture which naturally breeds in ponds throughout the year in 2ndian conditions with two peaks of spawning. etc. The female on the other hand has a bulging abdomen with a papilla-like outgrowth with a median slit in the vent region.A. well cared and well fed for the rest of the season and during the end of the breeding season they are again induced to breed by the same techniques. Fish usually spawn within %"'%! hours.1 / g! gation and ca! o' matu! 'ish ?ealthy and matured male and female brood fish should be segregated and kept in separate ponds usually by April and 5ctober. one during 0anuary to $arch and the other during 0uly1 August. . @.1. :ufficient quantity =double the weight of the female fish> of fresh aquatic weeds such as ?ydrilla. recovery from shock and severe stress is difficult under 2ndian condition and hence they should not be released back into the broodstock pond. .1.).a9as. Ase of anaesthetics during stripping minimises shock and stress and brings ease in stripping operation. 2n the case of silver carp and grass carp females.. where stripping is the normal practice. ?owever. if the stripping is easy and fast.2 9! ding t chni"u Fully mature male and female brood fish are selected for breeding and kept either in breeding hapas or cement cisterns. A mature male easily oozes milt when the abdomen is gently pressed. <efore releasing them back to ponds they should also be given a dip treatment in potassium permanganate solution to prevent any fungal attack. The yolk is absorbed within !'. The weeds are removed very carefully from the hatching hapas and the spawn are removed during the early morning hours. Fertilized eggs are dirty pale in colour and more or less transparent.the hatching takes place in about . ?atching ?apas in a @ond . This is the fingerling stage of the fish seed which should be used for stocking the composite fish culture ponds. About % kg of weed with attached eggs should be kept in each hapa.* mm in length with a prominent yolk sac. measured with a seive cup and transferred to nursery ponds. the percentage of fertilization can also be estimated. The incubation period depends upon the water temperature and varies from )&'6! hours. %7&&>. At a temperature of about !+')%H. The newly hatched out larvae are . <y e amining several samples of eggs. days after hatching depending on the water temperature. )%> fi ed in the pond. Dach gram of ovary contains about 6"" eggs =Alikunhi. this early stage of fish seed is not suitable for stocking in all types of ponds. ?owever. The weeds with attached eggs should be transferred to the hatching hapas =Fig. whereas unfertilized eggs are opaque and whitish in colour.The difference in weight of the female before and after spawning gives the estimate of eggs released.*'*" hours. The spawn is nursed for ! or ) weeks up to fry stage in nursery ponds and then the fry =!') cm> are transferred to rearing ponds where they are reared for three more months up to fingerling =+'%! cm> stage. -ollected spawns are sieved through a coarse mosquito netting cloth to remove debris. An allowance of %!'%*( should be given for faecal droppings. Figure )%. The newly hatched out larvae adhere to the leaves of the weeds and remain in this condition for some time.'*. @. carps require natural food and many feel that at least *"( of the food ingested by them should be the natural food items. not only provides the essential nutrients such as proteins.1 Natu!al 'ood :ome of the cultivable fish species such as trout.-ladocerans . natural feed is always supplemented with some artificial feed to achieve optimum production.@olyarthra sp. . . @hytoplanktonF -hlorophyceae <acillariophyceae $y ophyceae <. . salmon.2. carbohydrates and fats. . JooplanktonF @rotozoans 8otifers . in addition.2 F d Andrainable ponds have the ability to continuously supply natural fish food for the cultivated carp species. A brief account of the natural food available in undrainable ponds and the supplementary feed used in fish culture in undrainable ponds is presented below. etc.<ranchionus sp.atural feed. eel. As such. <ut the quantum of the natural food usually available in the pond is not sufficient to support the dense fish population cultivated under semi-intensive and1or intensive fish culture systems. -rustacea .$oina sp. . flagellates and -iliates . ?ence the availability of natural feed is one of the ma9or factors contributing to fish production in undrainable ponds.1 (!incipal natu!al 'ish 'ood An undrainable pond ecosystem provides a wide variety of natural food to the fish. The following groups of organisms are important =Figs.2. but also takes care of the much needed vitamins and minerals to the cultured fish which may not be present at the desired levels in artificial feed unless otherwise fortified..atural feed.:arcodines. etc./eratella sp. being balanced. @. A.@. are e clusively fed on artificial food. possess some of the essential amino acids and fatty acids required for growth while most of the artificial feed may be deficient.4iatoms .Asplanchna sp. )!A and )!<>.1. 5n the other hand. .Kreen algae .<lue-green algae . -.. .epidopterans.5stracods . ?emipterans. -eriodaphnia sp.$acrobrachium sp. Trichopterans. -yclops ..-ypris sp. and . JoobenthosF 2n addition to some species of -ladocerans and 5stracods. the following groups are also represented. . Eiviparus sp.-ida sp.-opepods . -rustacea .auplii 4iaptomus sp. $olluscs .ymnaea sp.amellidens sp. :tenocypris sp. .5donatans. bacterioplankton. #ater mites Aquatic insects . 2n addition to these. . detritus materials coated with bacteria and periphyton are also equally important as natural fish food. -oleopterans and 4ipterans.@ila sp.. $ost of these particles originate from the decomposing macrophyte remains. the size of the fish reared and on fertilization programmes. -arp species have their own preference for natural food which varies with the different stages of their life cycle =Table %!>. The natural food produced in the pond are varied and are able to cover the entire choiced food spectrum of all the si species of carps cultured together.>. The sediment detritus constitute the food of benthophagous fish species which utilize it directly. Table %! . the water which has been used to refill the pond. rotifers. stocking density.the phytoplankton and macrophytes which form the food of fish and herbivorous zooplankters. 5rganic manure containing practically all necessary nutrients required for biological production. -rustaceans. rotifers and algae. 4etails about pond fertilization with organic manures and inorganic fertilizers are discussed in the ne t section of this manual. rotifers -rustaceans. rotifers F!y Fing !lings -dult @rotozoans. rotifers. 2n the presence of sufficient food and favourable environmental conditions. wind-borne encysted organisms =copepods.atural food preferences of the Asiatic carps at different stages of their life cycle /tag s o' li' cycl /p ci s $a!*a -atla =-atla catla> @rotozoans. whereas in old ponds the bacterioplankton population is found to be the highest. The quantity of bacterioplankton depends on the primary production and the added organic matter. etc. the main among them being the portion of the ponds that never dried. . etc.The aquatic bacterial community while regulating a large number of important processes in the pond energy flow and mineral recycling. This helps the growth of primary producers . the bottom soil with organisms in hibernation or their encysted stages. The sources from which the nutritive fauna develops in the ponds are numerous. @lanktonic detritus particles associated with bacteria are freely suspended in the water column and they serve as food for filter feeders. algae.1. @.2 -*aila3ility o' natu!al 'ood 'o! 'ish in ponds The availability of natural food to fish in ponds depends on the quality and the quantity of the standing crop which in turn is determined by the e tent of e posure of the pond to fish culture.2. the bacterial numbers are much less. encourages bacterial growth which in turn favour better production of zooplankton and increases the effectiveness of many inorganic fertilizers by providing necessary organic matter base. eggs laid by insects. @ond fertilization helps in increasing the amount of natural food in the pond through the supply of the necessary nutrients which are either lacking or are insufficient in the pond ecosystem. species stocked. these fish food organisms multiply at a faster rate. 2n newly constructed and desilted ponds. The fauna associated with the sediment and the macrophytes have relatively longer generation time than the planktonic organismsG even then they occupy an important place in the natural food resources for the pond fish. also serve as food for several carp species. cladocera. unicellular algae. plant fragments. etc. spirodela. 4etritus and microzoobenthos. rotifers. mud S detritus.do - Eegetable debris. $ainly phytoplankton. etc. and crustaceans. lemna. Eegetable debris. moina. cereodaphnia. nauplii. -ommon carp =-yprinuscarpio> Ear. rotifers. crustaceans. oscillatoria. chironomids. ceratophyllum. phytoplankton crustaceans. Anicellular planktonic :ilver carp organisms. Falagellata. pieces of macrophytes. detritus. detritus and mud. worms.unicellular algae. crustaceans. aquatic plants. etc. -opepods. copepod nauplii. @rotozoans. 4iaptomus. $rigal =-irrhinus mrigal> . -ommunis 8otifers. cyclops. cladocerans and phytoplankton. diatoms. moina. bacillariophycea. some vegetable debris plant matters. ostracods. rotifers. na9as. unicellular algae detritus and mud. rotifers. <lue-green and filamentous algae.do - -rustaceans. etc. Krass carp =-tenopharyngodonidella> @rotozoans. chara. nauplii. insects including chironomid larvae. etc.abeo rohita> . ephemerids and trichopterans. =?ypophthalmichthysmolitri > nauplii and rotifers. etc. . hydrilla. 4ecayed vegetable matter. microscopic plants. etc. dinoflagellata. Aquatic plants such as wolffia. rotifers. Eegetable debris. microalgae. molluscs. @rotozoans. euglena. my ophyceae. cereodaphnia. decayed vegetable matters. planktonic algae. cyclops. cereodaphnia. 8ohu =. detritus. moina. @rotozoans. atural Fish Food 5rganisms =@hytoplankton> .Figure )!A. . . . crude protein constitutes . plastic pools.2.> can be cultured on a mass scale in earthen enclosures. $oina sp... collected from nearby ponds.> and cladocerans =<osmina sp. After the treatment.2 /uppl m nta!y ' d The fish production rate may be increased significantly by merely supplementing the natural food with artificial feed which can support more fish with increased individual weights. seeding is done with !'* ml of $oina sp. All the carp species including the predominently plankton feeders like catla and silver carp and macrophyte feeder grass carp accept supplemental feed. -hemical analysis of plankton show that on an average.. and subsequently after every four days at the rate of half the initial dose. . %7+*>. @lankton has relatively small amounts of fat averaging to about *'6(. @. etc.( to more than *6( of the dry organic matter. $oina thus cultured may be used for seeding nursery ponds at the rate of )"'*" ml of $oina1ha =0hingran and @ullin.atural Fish Food 5rganisms =Jooplankton> :ome of the fish food organisms such as rotifers =<rachionus sp.Figure )!<. -ow dung and oil cake are applied initially at the rate of !*"')*" ppm and *" ppm respectively. tanks. resulting in a more profitable operation. and may be inoculated into the nursery ponds. 4aphnia sp. %" ' . 2n <angladesh.2. the most common fish feed is the mi ture of mustard oil cake and rice or wheat bran. dietary protein quality. fat. the amount of non-protein energy in the diet.)% Though dietary protein levels have been shown as optimal for fry and fingerlings of 2ndian ma9or and common carps =Table %)>. :maller aquatic weeds such as wolffia. The quantity and quality of nutrients required by carps for attaining optimum growth vary with the species.*" . @rotein requirement levels of some carp species are given in Table %).2. @. Dssential nutrients such as protein. farmers are advised to feed a mi ture having maize..*" ' .epal. rearing and stocking ponds. (!ot inF @rotein requirements may be looked at the gross protein and specific amino acid requirement levels. =%76+> :in =%76)> :en et al. The same feed is applied in nursery. ?owever. a balanced supplementary feed can be compounded without any significant increase in its cost which will give better results than the conventional one. lemna. essential minerals and trace elements.. are provided in the early stages while large macrophytes and green animal fodder to the bigger fish. production of energy and also to regulate the vital physiological processes. finely chopped vegetable matter or grass are also mi ed. quality of the protein in terms of its amino acid .> 4abrowski =%766> -ommon carp . Aquatic weeds or sometimes green animal fodder are given to grass carp. =%76+> :ingh et al. size and stages of the life cycle. @rotein requirement is influenced by several factors like water quality. 2n 2ndia. etc. stocking density. the background knowledge of the nutritional requirement of carps becomes essential for formulation of suitable balanced supplementary feed.1 Con* ntional ' ds The conventional supplementary feed is usually a mi ture of brans and oil cakes in %F% ratio by weight.2 9alanc d suppl m nta!y ' d Asing locally available feed materials and mi ing with vitamin premi . etc.. natural food availability in ponds. wheat or rice bran and mustard oil cake.*" . 2n . 2n certain regions. =unpubl. vitamins and minerals are required as raw materials for the formation of body tissues. spirodela.+" 8ohu $rigal Krass carp .2.@. carbohydrate. oil cakes such as mustard oil cake or groundnut oil cake and rice or wheat bran are widely applied depending on their local availability. Table %) @rotein requirements of certain carps /p ci s C!ud p!ot in l * l in di t 'o! optimal g!o%th 0g56g2 R ' ! nc :en et al.2. :inha and /umar.7 %.* )+. Dssential Amino Acid requirements of common carp =-yprinus carpio> =Adapted from . diets containing over .. ?owever. =Table %. %767G :en et al.ysine $ethionine L @henylalanine LL Threonine Tryptophan Ealine L 2n the absence of cystine LL 2n the absence of tyrosine B o' p!ot in . )+.% !.& ".eucine .) %.6 ).& B o' di t %. @lant proteins are deficient in certain essential amino acids like methionine.>.* )+. while for mrigal fingerlings it is !+( in synthetic diets =:ingh. *.* %. Although higher levels of carbohydrate may be utilized by carps..! !. bone meal. =unpubl.* )+. $ipids7 The polyunsaturated fatty acids =@AFA> is considered to be the most important class of lipids as far as lipids are concerned.composition is important or else growth would suffer even if the dietary protein level is high.* )+.ational 8esearch -ouncil. the protein requirements of carps can be brought down to some e tent by raising the level of dietary carbohydrates.* Total p!ot in in th di t 0B2 Ca!3ohyd!at s7 -arbohydrate requirement of carp species is highly variable ranging from %"'. Table %.* )+.) !. %76+>. -ommon carp utilizes !*( carbohydrates effectively as energy source =Takeuchi.>.* )+.* )+.! %. #atanabe and 5gino.) ).+ ). .! !.* )+. -arps can derive their lipid requirement from natural feed available in the pond since these compounds are readily available in planktonic and other biotic communities.* ).7 ". Their quality can be improved by the addition of animal proteins such as fish meal.*(. %7+)> 8equirement -mino acid Arginine ?istadine 2soleucine . etc.* "..+ ". blood meal..* )+.% &. The most likely symptom of over supply of carbohydrates in diet is e cessive deposition of fat in the liver and carcass."( de trin results in retarded growth and lowered feed efficiency due to lower digestibility.ipids are also considered to be the most important sparing . a T .ervousness and fading of body colour.idcotinic acid <iotin Folic acid Eitamin <%! -holine 2nositol Ascorbic acid Eitamin A Eitamin 4 Eitamin D Eitamin / !+ % N . Table %* 4ietary vitamin requirements of the common carp =-yprinus carpio> and related deficiency symptoms =From .itamin Thiamin 8iboflavin @yrido ine R "ui! m nt 0mg56g di t2 Na 6. T . mortality @oor growth .+ to ).one detected . mortality . The values of quantitative requirements of vitamins in common carp and the symptoms of their ma9or deficiencies are presented in Table %*. e ophthalmia.ot available . hemorrhages on fin and skin .itamins7 :tudies on vitamin requirements of fish are very limited. ..one detected @antothenic acid )"'*" . skin hemorrhages. <y adding *( of soyabean oil the optimum protein requirement of young mirror carp can be brought down to ))( from )+(. ?emorrhages on skin.compounds. %7+) and other sources> ." *'& MaAo! *itamin d 'ici ncy symptoms . mortality .one detected $uscular dystrophy.o dietary requirement demonstrated under variousenvironmental condition.ational 8esearch -ouncil. The addition increases the dietary metabolized energy from !." Na %" """ 2A N !""')"" N . . fin. . anaemia.one detected Fatty liver :kin lesions 2mpaired collagen formation Faded colour.% /cal1g.ervous disorders @oor growth. """ . e ophthalmia ?emorrhages on skin. banana.. . 4igestibility and absorption greatly vary with the quality of the feedstuffs and also from fish to fish. Common ' dstu''s7 A large number of feed stuffs are presently being used as supplementary feed for carps in undrainable pond culture systems. silkworm pupae and items like snails. maize. :laughterhouse offals. %767> reported that cobalt chloride and manganese at the rate of ". molybdenum. etc. beer brewing or rice-wine industry wastes can be profitably used as fish feed.. bone meal.&'". wheat and other grains are equally popular and used in combination with oil cakes. . paranapier. magnesium and phosphorus and trace elements such as cobalt. coconut.eafy feeds are suitable for grass carp. colocasia. copper.. <roken cereals such as rice. sweet potatoes. carps appear to be less sensitive to mineral deficient diets than other fish possibly due to meeting their dietary mineral requirements from natural sources under pond culture condition. prawn head meal. linseed. sulpher. are also used. etc. Tender leaves of various aquatic and terrestrial plants =cassava. 4ried fish meal =fish flour> is the most common and cheapest source of animal protein and widely used in livestock and fish feeds. $iscellaneous items such as kitchen wastes.6( and that of calcium is about ". are a most useful and widely used feedstuff of plant origin with high fat and protein contents. manganese. :ome of them are widely available and e tensively used. oligochaete worms.( dry diet of iron.Min !als and t!ac l m nts7 .ike higher vertebrates. etc. zinc. are also widely used depending on their availability and price. -akes of oil seeds such as groundnut. fry and fingerlings of 2ndian ma9or carps. These may be broadly classified into two groupsF the feeds of plant origin and the feedstuffs of animal origin. elephant grass. carps also have dietary requirements of minerals such as calcium. <rans of rice. iron. household scraps. maize. residues of bakery. fluorine. 8ohu requires about ". etc. are good but e pensive feed materials. iodine. maioc. napier.utritive values of some commonly used feedstuffs are presented in Table %&. 2n general. :uch meal as soya waste after oil e traction is e cellent feed for carps. etc. @ro imate composition of some of the common fish feed stuff =Adopted from A4-@. :en and -hatter9ee =%76&. The values of total digestible nutrients in common feedstuffs are given in Table %6."% mg1day1fish gives higher rates of survival and growth of spawn. %( dicalcium-phosphate is recommended in the feed for adult fish in polyculture system in ponds.> and green animal fodder such as berseem. For common carp the minimum requirement of phosphorus in the diet is "."!+(. mustard. =%7+)>> -s p !c ntag o' d!y matt ! Common nam DM CP EE CF -sh NFE Ca P M thioin C c=stin $ . wheat. etc. Trace elements are growth stimulants and are required in traces.. Ta3l 1."%. 6 *!...% .% %)." %.) .6) "...! "." !.* *.* &.% &.% )%." 7".& %+." %.& !." %!.6 +6.7* "." %6.. %.) +.7 %6.) )7..6 %".." ".% %.. %.!% "..+ ).&..+ ++..* )&.." )..& %. ++.% *.% ".7 "... @lant product Kroundnut oil cake Kroundnut oil meal -oconut oil cake :oyabean cake :oyabean oil meal -otton seed oil cake :unflower oil cake :unflower oil meal .) +.* )!.% 7." +%.7 &.*! ".) %+.& &.inseed oil cake :esame oil cake Kround maize #heat bran 8ice bran 8ice polish $illet <lack gram bran <.! . !.) 7%.& 7".6 ." 6.! +.6 )6." &.7 ++.! ".! %&." +&..*+ ". !"." %.7 7%.7 %).7 )*.* 6*.%) ".%" ".+ ." +.* *!." ".6 )".). %&..! ".*6 ".% !".&7 %.6* "." 6. +.!." %%.! *.." !%." +7." %!.6.& &.*! "." %!.)" ".! %&.6 7!.+ !7.7& ).!% ".) ".7.+ .& ..& ).% %." .6 %. %... 6. ).).! %+.& %.%! %.! &".)" ".. .+ ".6.! ". *. %.+ ).* ".) *.! !!." &.+ ). ".! *.! %%.7 !*." &..6 +. %...* ".)& ".7 %). ).6 "...& )%.).7 *&.".& 6.." **.)& %...* 6." +7.&.7 +.6 )".6 7%.% )6.% "..!+ %".! %." +7..*+ "." %%.& ++.! %).* !".!* 7. Animal products <lood meal <one meal Fish meal @rawn meal :ilk worm pupae Fresh cattle manure +7.) !..)6 "..." 7".! %. "." .7 &&.!+ !!.+ !&.* .& &.A.& - .% .+..6. %!.7 ).!! ".% .6" %.% %. %.% %.7 !!.* ".% ". %.) ).* *.) )." +.! ..6 %!. ! ).Dther e tractG -F .+ +. minerals and trace elements are added as required.) Dig sti3l nut!i nts 0B2 Fo!mulation o' ' d7 Dasy availability. The initial step involves surveying market prices of the locally available feedstuffs and tabulation of data as mentioned below as an e ample =Table %+>.4$ . high digestibility and high nutrient contents are the ma9or considerations in selecting the fish feed ingredients for feed formulation. Eitamins. Asually the crude protein level of the supplementary feed is fi ed at about * to %"( below the dietry protein requirement of the fish to be fed.a diet basically to supplement energy and a portion of protein and other essential nutrients. Ta3l 18 Ealues of digestible nutrients in carps for some common feedstuffs F -oconut oil cake Kround nuts 8ice bran $aize =-orn> $aize =fresh> 8ye :weet potato 8adish leaves Fresh silkworm pupae dstu'' &6.) 67.FD .-rude proteinG DD . Feed constitute the ma9or operating cost in undrainable pond fish culture and therefore. Ta3l 1@ .7 6..-alciumG @ .Total phosphorus.4ry matterG -@ . Formulated feeds may be either a complete feed with optimum level of all the essential nutrients and energy to provide complete nutrition or a supplementary feed .. 2n undrainable pond culture systems where natural feed are made available by pond fertilization. feed is required only to supplement the natural feed.itrogen free e tractG -A . low cost. our ultimate ob9ective is to supply essential nutrients at the minimum possible cost.-rude fibreG ... 66.% 6*.7 ' 6*.* ' &7.7 !*.+ 67. & kg of sesame seed cake and %".)(> 4esired feed protein level=)"(> 8ice bran=@rotein %"(> )!. out of the three listed above one can easily select the feedstuff most suitable for his operation. Asing the locally available feedstuff.) T !!. :esame oil cake=@rotein )!.%% F dstu'' (!ot in cont nt )+. 22 222 2 +!ad 'o! s l ction 0U/ D2 Kroundnut oil cake $ustard oil cake :esame oil cake Thus. The two selected feedstuffs with their percentage of protein content are put on the left hand corners of the square as shown below. The same method can also be used to . :imilar methods may be adopted to find the best possible feed for the supply of specific ma9or nutrients.).! Cost56g p!ot in ".! . The two resultant figures on the right hand side of the square are then added together =!" L !.)Total !!.*! ". . a diet with desired level of protein can easily be formulated by using the square method. Thus.4ata tabulation e ample for selection of feedstuff Ma!6 t p!ic 0U/ D56g2 ".%* ".)>. Their amino acid profile is also to be considered for such selection. The required protein level of )"(.!% ".)7 ".!Q)" T !." )!. for e ample.) )"Q%" T !" The value of desired protein level of the proposed feed is substracted from each of the feedstuffs in turn and the results are placed at the opposite corner ignoring the resultant positive or negative signs.ow to obtain )"( crude protein level in the proposed feed. to obtain )"( crude protein level in %"" kg of feed we need +7. The same method is also used for ad9usting energy levels in a feed. is put in the centre of the square.) kg of rice bran to be mi ed together. the following formula is followed. lysine. by pelletization of supplementary feed mi ture. Figure ))A. Eitamins. water-stable pellets by the process of heating and compression. Fish Feed in 4ough Form . the requirements of & other essential amino acids usually also get satisfied. Feed in pellet forms are more readily acceptable and give better results in comparison with dust feed =/umar et al. 2t has been e perienced that if the minimum dietary requirements for amino acid like arginine.>. %7+. ?owever. Dven in undrainable ponds use of supplementary feed in pelleted form promise increased production through increased efficiency and minimum wastage =Figs.obtain a desired dietary energy level. methionine and tryptophan are met.. minerals and trace elements are added in feed according to the requirements of the species of carps under culture. the soft and dusty feed is converted into hard. ))A and ))<>. 4uring pelletization. such wastage can be minimised and further improvement in the feed efficiency can be achieved. ( ll ti=ation7 -onsiderable wastage is e pected when supplementary feed mi tures rapidly separate into their component ingredients during the feeding process. + "." !. Table %7a .utrients specifications of commercial aquaculture feeds =#arm water omnivorous species> =Adapted from A4-@.& %." %.* %." F!y and 'ing !lings !* * Eu* nil s and adults 9!ood Fish )" * ".Figure ))<.+ %.+ %.* ".+ ". Fish Feed in @elleted Form A generalised but practical account of nutrient specifications of commercial warm water aquaculture feed is given in Table %7a.* %.ysine =( min> )" + ". %7+)> Nut!i nts @rotein =( min> .& %.ipids =( min> -a =( min> -a =( ma > @ =( min> @ =( ma > ." %.& .* ". "." !.." *." !..) !.. "..! !." !." !." %!." %!.) !. !+" !+" .u.u." !.iacin =g> @yrido ine =g> <iotin =g> Folic Acid =g> -holine =g> <-%! =mg> $inerals =:upplement>." &"" """ %"" """ & """ %." !." ".." )." !.." !." %..=g> Thiamine =g> 8iboflavin =g> @antothenic acid =g> . "." ".& *.> D =i. &..* *".." *. !." !.." %"." !." ". A =i. 2ron =g> -opper =g> $anganese =g> Jinc =g> 2odine =mg> -obalt =mg> )%" =per %"" kg> &"" """ %"" """ & """ %." %." *"" """ %"" """ * """ %.& *.> 4 =i." ).> / =g> . !.."!" "."!." !." ). &."!. =per %"" kg feed> *.1%"" g min> Eitamins =:upplement>." %"." !"." %." %"." *.u. "." %".4igestible Dnergy =/ca..) !." ". These nutrients are broadly divided into two groups. carbon and calcium. $ost of the organic manures are by-products of local agriculture. They also come in the form of farmyard manure. animal husbandry and village based agro-industrial activities and hence their procurement is relatively easy at low cost." %". ".%( mineral mi ture. phosphorus. while the second group of nutrients which are needed in very minute quantities constitute mainly copper. 2n other words. molybdenum. fingerling and brood fish are under e tensive trials to determine which would be the preferred formulations in terms of efficiency and cost. etc." %".1 O!ganic manu! s 5rganic manures have been in use in fish culture in 2ndia and the Far Dast countries for a long time. green manures. cow dung is the most widely used manure in undrainable pond culture system. ". @. They are available in a variety of forms such as dung of cattle. minerals and vitamins and rapidly separates into its component ingredients during the feeding process. including organic carbon. boron. pig and goat. potassium. poultry droppingsG de-oiled cakes of mahua. Although mineral and vitamin mi tures are commercially available as common additive of animal feed. etc. cobalt. 2t is the first group of nutrients which are more concerned with pond fertility in terms of primary production. compost. <y improving the quality of the pond bottom mud they encourage bacterial growth which in turn favours better production of zooplankton and also through inducing increased bacterial decomposition help in releasing mineral constituents of the soil into the water. sheep. @. castor. required for biological production. They are composite in nature and provide practically all the nutrients.:elenium =mg> %". mustard. zinc. the required amount of nutrients need to be replenished. iron. Though the presence of the ma9or nutrient elements in these manures . 5f these." <ased upon the nutrient specifications. etc. Fertilizers are also classified into two categoriesF inorganic fertilizers or mineral fertilizers and organic fertilizers or manures of plant and animal origin. consumed in more quantity and thus need to be compensated from outside in the form of fertilizers. 2t also increases the effectiveness of many inorganic fertilizers by providing the necessary organic matter base. linseed.# F !tili= !s -onsiderable quantities of nutrient elements are regularly removed from the pond ecosystem through the harvested fish crops and thus for retaining the pond fertility. -onsiderable improvement is possible if this conventional rice-bran and oil cake mi ture is simply fortified with %*'!*( fish meal. manganese. :everal organic manures are immediately assimilated by the aquatic fauna and especially by the zooplankton or even by some species of cultured carps. The conventional rice-bran and oil cake mi ture lacks animal protein. neem.#. a number of test diets for carp fry. fish meal at a reasonable price may not be easily available in rural areas. the main ob9ective of adding fertilizers in fish ponds is to maintain a sustained production of natural fish food during the entire culture period.%( vitamin mi ture and pelletized. sewage. The first group of nutrients are nitrogen. 2.#. Further. phosphatic. etc. $uriate of potash =/cl> and sulphate of potash =/ !:5. @. 2t is all the more important because almost all fish ponds e hibit phosphorus deficiency.nitrogen.is rather at a lower level and often vary quantitatively. Amongst the phosphatic fertilizers. in the pond water is likely to occur with consequent loss of fish by asphy iation. ratio at %1.1 Nit!og nous ' !tili= !s . The more concentrated triple superphosphate is also in use which has @!5* =@hosphorus pentao ide> equivalent up to . unless proper care is e ercised in its use. its importance in pond fertilization is less pronounced since it is available in a required quantity in natural waters. the form of nitrogenous fertilizers may be selected on the basis of acidity. thereby making the procurement. 2t is best to maintain the @1. @. @.2 (hosphatic ' !tili= !s @hosphatic fertilizers are by far the most effective and favourable for fish culture. ammonium nitrate.#. ?owever.#.2 Ino!ganic ' !tili= !s -ommercially produced inorganic compounds containing ma9or nutrients . whereas older ponds having a good layer of colloidal mud are capable of producing nitrogen by itself. their effect is sustained over a longer period.itrogenous fertilizers are particularly essential for newly constructed ponds which are poor in nitrogen and do not have sufficient organic matter in its bottom.> are the two commonly used . phosphorus and potassium are known as inorganic or chemical fertilizers. :ome fertilizers are also available in liquid form which offer several advantages over the conventional granular or powdered form of fertilizers. :uperphosphates are the most soluble in water.2. @.# (otassic ' !tili= !s Although potassium ranks as a ma9or nutrient like nitrogen and phosphorus. the nutrients become readily available soon after their application. depletion of dissolved o ygen. . better yields of fish are obtained through a 9udicious manuring schedule. transport and application somewhat troublesome and costly though the manure itself is cheap. urea. dicalcium phosphate is partially soluble and rock phosphorus is almost insoluble in water.2.#. ?owever.itrogenous fertilizers usually contain nitrogen as the principal element and are commercially available as ammonium sulphate. Also. $ost of the nitrogenous fertilizers deplete reserves of bases and make soil acid. neutrality or alkalinity of the soil type =:aha. %7&7>. The most commonly used phosphatic fertilizers are the orthophosphates and are grouped roughly according to their solubility in water. mostly depending on the nature of the pond bottom. the phosphatic fertilizers are held in soil and liberated gradually with the result that its action is e tended to subsequent years of its application.*( with +*( solubility and thus involved relatively lower transport cost. 4ue to their high solubility in water. Therefore. they are required in large quantities. Kenerally. potassic or mi ed> of fertilizer.. They contain a high and fi ed percentage of one or more ma9or nutrients depending on the class =nitrogenous. single superphosphate is e tensively used and is easily available. the efficacy of nitrogenous fertilizers is inhibited by phosphorous deficit. ?owever. cause deterioration in the quality of inorganic fertilizers and hence only a specified quantity of materials required for !-) months should be procured at a time. @rolonged storage.%& ". the freshwater flora.utrient profile of some common manures and fertilizers used in pond fertilization Nut!i nt cont nt 0B2 It ms Nit!og n 0N2 (hosphat as (hospho!ic 0acid0(2F.2. due to e tensive adoption of intensive crop farming there is a growing demand for animal manure or compost in agriculture. @.#. for ponds in which phytoplankton production is rather slow. #hile storing the manure. 2norganic fertilizers being e tensively used as an agricultural input.)* ".fertilizers as a source of potassium. Table %7b . high humidity.) Calcium Though calcium is not considered as a nutrient to be used as fertilizer. molluscs and crustaceans are either rare or absent which in turn diminishes the nutritive value of the water. 2n ponds where the water is poor in calcium =less than + mg -ao1%>."" . etc. -alcium present in required quantities also neutralises the harmful action of e cessive magnesium. :election of fertilizers depends mainly on their nutrient content.. 5rganic manures are locally available and in most cases they are available within the community. cost and suitability for the specific soil condition. 2nstead of procuring the whole lot of required manures at a time and storing them for application over e tended periods. 2t is usually applied in the form of lime. -omposition of some important manures and inorganic fertilizers commonly used in pond culture are listed in Table %7b.2 (otassium as (odtash 0G2F2 Fresh e creta of animalsF -ow :heep ". it is another integral part of the ecosystem and is usually applied to get the benefit of added fertilizers used in a pond. the listed fertilizers =Table %7b> are easily available in the local markets. it is always convenient and desirable to procure materials in small quantities and apply them as and when required. The favourable action of potassic fertilizers can be seen in ponds with low alkalinity.. 2t also improves the hygienic conditions of fish ponds. @rocurement of organic and inorganic fertilizers is relatively easier than other essential inputs like feed and seed. it should be covered to protect it from direct sunlight. potassic fertilizers may be tried. which is widely available as ground lime stone =-a-o )>.* %. sodium and potassium salts.7* ".&" ". particularly the rearing ponds. slaked lime =-a=5?>!> and quick lime =-ao>. with peaty bottoms. 2n general. .% ' ".*.)'.* %&."" ". ' ".& "."'." - - - .7 ".+ !.+ %.* "..+ ' ".*" ".". (OND M-N-+&M&NT ..* ' ".6 "." %.+ !"." . ' ".+.7 . ' ".6."'!"."" %.* ".6 ' %.&" %."'&!.* ." ".! ".&! "." - - - %&.) %.+ ".+ ".* !.." %." H.) ' ".itrogenous Ammonium sulphate Area Ammonium nitrate :odium nitrate @hosphateF :ingle superphosphate Triple superphosphate @otassicF $uriate of potash :ulphate of potash "..* %.* !".&" ".."'*".@ig 4uck ?en 4eoiled cakesF $ustard Kroundnut $ohua 5thersF Farmyard manure -ompost Kreen manure 2norganic fertilizersF ." %.* 6.+ ".* ' %.* ' !." .* ' %. and slackness at any stage of the management procedure may affect farm productivity and profitability adversely. To ensure high rate of survival and growth during all the three stages of rearing. the various steps involved in the management of ponds at all the three stages of culture may be classified as =i> pre-stocking.1 (! :stoc6ing manag m nt @re-stocking management aims at proper preparation of ponds to remove the causes of poor survival. 2n addition. supplementary feeding and health care. and also to ensure ready availability of natural food in sufficient quantity and quality for the spawn1 fry1fingerlings to be stocked. Dven the poor fish crop that is produced in weed chocked water is difficult to harvest. unsatisfactory growth. emergent.. @restocking part of the management involves the following sequential measures. pistia.1 &!adication and cont!ol o' a"uatic % ds and alga Aquatic weeds are unwanted plants that grow within the water body and along the margins. a package of management practices should be strictly followed. Anlike in temperate climate. etc. <roadly. 4ecomposition of the dead aquatic weeds further creates the o ygen problem. 4ense growth of the submerged weeds restrict fish movement and interfere with fishing operations. into four ma9or groups. the pond fish culture in tropics face serious problems due to weed infestation and frequent appearance of algal blooms. ). thus resulting in critical reduction in primary productivity of the pond. very often cover the entire water surface cutting off light drastically. Floating weeds such as water hyacinth. H. =ii> stocking and =iii> post-stocking management operations. Techniques of management involve =i> manipulation of pond ecology to ensure optimum production of natural fish food while maintaining the water quality parameters within tolerance limits of the stocked fish speciesG and =ii> the husbandry of fish through stock manipulation. Filamentous algae often get entangled in the gills of the fish and suffocate them to death.1. which otherwise would go into the production of planktonic growth. algal blooms and mats also create serious problems in terms of dissolved o ygen and production of certain to ic materials in some cases. The fishes are sub9ected to stress due to dissolved o ygen depletion and wide fluctuation between the dissolved o ygen values of the day and night. etc.. -ommon aquatic weeds creating problems in fish culture ponds =Fig. . They are floating.> are broadly classified according to their nature of occurrence. submerged and marginal. They remove a large quantity of nutrients from the water. H.-arp culture in ponds is basically a three-tier culture system where the first step begins with the rearing of spawn up to fry =!') cm> stage for !') weeks in nursery ponds followed by rearing of !') weeks old fry for about ) months up to fingerling stage =+'%! cm> in rearing ponds before they are finally released in stocking ponds for growing up to table size fish. Aquatic weeds of common occurrence in undrainable ponds are grouped in the following Table =Table !">. Figure ). -ommon Aquatic #eeds in Anderainable @onds Table !" Kroups of commonly occurring aquatic weeds. algal bloom and algal mats +!oups Floating /ci nti'ic nam Dichhornia crassipes Common nam #ater hyacinth . algal bloom and algal mats in undrainable ponds Aquatic weeds.. .ymphea tuberosa .ymphoides spp. . manual and mechanical.@istia stratiotes :alvinia cucullata :pirodela polyrrhiza . pond condition.ymphea me icana . chemical and biological.emna minor Dmergent . viz.a9as -urly leaf pondweed Del grass 2pomea #ater primrose -at-tails -yperus $icrocystis <lue green algae ?orse hair clump Filamentous algae -ontrol measures for all the above mentioned classes of weeds and blooms fall into four ma9or categories. Typha anqustata -yperus spp. Algal blooms $icrocystis aeruqinosa Anabaena Algal mats @ithophora :piroqyra #ater lettuce #ater fern 4uck weed 4uck weed <anana water lily Fragrant water lily . preventive.elumbo spp. cost involvement and availability of required inputs. Any of these methods or at times a combination of methods may be taken up depending on the nature of infestation.otus Floating heart ?ydrilla . $arginal 2pomea aquatica 0ussiaea spp. :ubmerged ?ydrilla verticillata .a9as marina1minor @otamogeton crispus Eallisneria spiralis 5ttelia spp. The free floating groups of weeds are either hand picked or dragged by wire or strong coir rope nets. -ertain small and light floating weeds such as spirodela. uprooting or burning of dried marginal weeds during the summer and providing barriers to prevent the entry of floating weeds.2 Manual and m chanical cont!ol $anual removal of aquatic weeds is an age-old practice and holds good even today in rural areas. medium and big. As discussed earlier most herbicides are selective in nature and when applied to a mi ed population of weeds. Floating % dsF #ater hyacinth is one of the most important weeds of this group. Total kill and disintegration of weeds can be achieved by this method ensuring full return of the nutrients back to pond soil and water for production of natural fish food. H. Ander such conditions certain commercially available chemicals =herbicides> can provide an efficient means of eradication of undesirable aquatic plants. are easily skimmed out by twisted straw ropes or fine meshed nets. and hand forks.. lemna.1. Therefore.# Ch mical cont!ol The manual removal of weeds from heavily infested large water bodies is difficult and time consuming. they are categorized in three groups.1. viz. etc. H. based on their wet weight per unit area. dewatering and desilting of old ponds. when surface or floating weeds are destroyed. Ander such conditions subsequent application of appropriate herbicide should be taken up. As a matter of fact there is not a single chemical known so far which can eradicate all types of weed infestation. %7*&>. $echanical devices used for clearance of rooted submerged weeds are steel cables. wolffia.1. The manual removal of submerged weeds from a heavily infested water body is relatively much more difficult. certain preventive measures are to be followed to reduce the chances of their infestation. 4epending on its degree of infestation.1.H. The preventive measures have to be taken well in advance. appropriate herbicide and its rate and time of treatment. small. azolla. one must know the weeds and its species. 2n bigger ponds they should be removed part by part from the marginal areas and finally the centrally located weed mass is dragged towards the banks and lifted out. the herbicide should be applied part by part if the pond is already stocked with fish. The measures include trimming of pond margins. They are either pulled by hand or hand-drawn bottom rakes or uprooted with bamboo poles having a cross piece tied strongly at the terminal end. 8epeated cutting of the aerial shoots and leaves of rooted emergent plants are also useful. The recommended doses of the . strong nets and bamboo poles with terminal cross piece for twisting and uprooting =Fig. the submerged weeds develop. 2n larger ponds where dense infestation covers a substantial portion of the water.1.1. 2mplements used for manual control are mostly hand scythes for cutting. growth of some tolerant weeds may be encouraged at the cost of susceptible onesG likewise. )*>.1 (! * nti* cont!ol Taking into consideration the high cost of controlling aquatic weeds. cutting chains and diesel operated winches =$itra. ?and tools Ased for $anual -ontrol of Aquatic #eeds #ater lettuce which often causes a serious problem in fish ponds can be controlled with ". ! ! ! Figure )*.%'"."" l1ha.! ( of any commercially available detergent as a wetting agent. The dilution for better coverage has been estimated at . medium =!) kg1m > and big =)* kg1m > =8amchandran.ormally. This infestation could also be controlled by foliar spray of aquous ammonia =%(> at the rate of *"'6* kg1ha along with ". . the complete kill of plants takes around !* days. Addition of a detergent =". is a difficult task.! kg of paraquat1ha. The foliar spray =spraying over the leaves> is undertaken with the help of a foot pump1hand pump sprayer with a three-action nozzle. 2n such cases a pair of stout bamboo poles should be laid on the top of the infestations so that the operators can walk over them. Field application of herbicide.herbicide !'. especially towards the interior of thick water hyacinth infestation. %7&7G @atnaik and 4as.6 and %! kg1ha for small =%) kg1m >.! ( concentration> to the aqueous solution gives better results. . This chemical is available in two suitable forms as sodium and amine salt.-4 are !. %7+)>. 1. The area to be treated inthe field is divided into small plots =!"')" m size> and solution is sprayed at the rate of * """ %1ha. :imazine also clears the bloom in %&'!" days and the rate of application is ". Asually the chemical is sprayed over the affected portions of the ponds.* ppm is recommended. . and floating heart can be cleared by spraying the herbicide !'.The aquous ammonia is broadcast as foliar spray over the infestation with a foot pump sprayer and a small funnel'shaped sprinkler )'." ppm. Although repeated netting can reduce the infestation to a considerable e tent in nursery and rearing ponds.. The common mat forming algae which occur in fish ponds are :pirogyra. <oth the chemicals do not have harmful effect on fish. A number of chemicals have been employed to control these algal blooms.g.)'". Asually it takes )"'. :pirodela.emna and Azolla can also be cleared with ".) 9iological cont!ol o' a"uatic % ds . lotus. etc. Eallisneria. :maller floating weeds.4 at the rate of + kg1ha.! to %.1. Ma!ginal % ds7 2pomea. could be controlled by spraying the herbicide !'. 2t has been observed that the sudden kill of blooms is likely to cause o ygen depletion which might cause mortality of fish. but it is not very effective in ponds having high p? =p? above +.!*(>. :ome of the more harmful blooming algae are microcystis. 5edogonium and -ladophora. The stem of the sprinkler is connected to the sprayer through a )" m long polyethene tube. The recommended doses are ".a9as. so that the sprayer is kept on the shore and only the sprinkler is taken inside the infested area in a boat.% kg1ha of paraquat. anabaena and euglena.&>. 0ussiaea. .* ppm. 2n order to avoid this a prophylactic dose of diuron =". -opper sulphate is perhaps the oldest and a very widely used algicide. the minute algal cells multiply fast turning the pond water bright green or sometimes brickred. ! :alvinia forms a thick surface mat in ponds and can be conveniently controlled by the application of foliar spray of paraquat at the rate of % kg1ha.% ppm> should be applied in the very early stage of bloom development.) to ". ppm within two weeks.* ppm of 4iuron. 2t can also be controlled by application of anhydrous ammonia at the rate of %*'!" ppm. The chemical is diluted at the rate of )"" l1ha and sprayed through a footpump sprayer. @ithophora. Earious chemicals and the dose of application is summerised in the ready reckoner given below =Table !%>. @otamogeton and -eratophyllum can be controlled by paraquat at the rate of )'. H. e. -lgal 3looms and mats7 4ue to overdose of fertilizers or enrichment of the water through treated sewage or agricultural fertilizer. &m !g nt % ds7 #ater lily." days for the weeds to be killed and settled in the pond.)'". cm in diameter. application of 4iuron at the rate of ". provided with %" pin-sized holes pierced on the diaphragm covering the mouth of the funnel.-4 at the rate of +'%" kg1ha with detergent =". ?ydrilla. $icrocystis bloom is cleared with ". /u3m !g d % ds7 5ttelia. "" fish.1. 2f situation permits.!*( detergent ". are enough to clear % ha of ?ydrilla infested water body in about a month. water lily trapa. the grass carp and a species of puntius are the fishes of known weed-eating habits =Table !!>. etc. ! H. :alvinia -do@araquat -doKramo one + kg1ha %.!( detergents ". $arginal weeds . rearing and stocking ponds before these ponds are stocked.Another important controlling method is by introduction of weed-eating fishes.ormally ?ydrilla infestation density ranges from *'!* kg1m =Alikunhi and :ukumaran. .otus. From an economic point of view the poisoning should be done during pre-monsoon season when the water level is usually low. -ommon carp. should be fi ed about three weeks before the anticipated date of stocking.* kg weight.%'". dewatering should be the preference as it ensures complete eradication of unwanted fishes and disinfects the pond bottom.'4 =sodium ?e amar salt1amine salt> Ferno one -do-do- !'%! kg1ha !. the pond should be treated with fish poison. space and o ygen. pearl spot. Krass carp is the most effective biological control agent against most of the submerged and floating weeds e cept the water ferns. The date of poisoning. Therefore predatory and weed fish should be completely eradicated from nursery.>.. each of about ". Krass carp normally consumes choiced aquatic weeds.!*( detergent - %. ?owever. About )""'. Absolute removal of these unwanted fish by thorough and repeated netting is not possible and hence dewatering and poisoning the pond are the only alternative methods. fry and fingerlings of carps and the weed fish compete with carp for food. . #ater hyacinth pistia and other floating weed Taficide !'. where it is not possible. tilapia. 4ewatering also offers the opportunity to desilt the pond bottom. however. which is true in most situations. requiring the minimum quantity of poison material. at least *"( of their body weight in a day. %7&. Table !% 8eady reckoner for chemical control of aquatic weeds W ds H !3icid 9!and nam Dos -dditi* s ".2 &!adication o' un%ant d 'ish @redatory fish prey upon the spawn. +'%" kg1ha )." kg1ha . gourami. :easonal ponds which dry up during summer months need not be treated with fish to icants. The commonly encountered predatory and weed fish in undrainable ponds are listed below =Table !)>. a9as. 8ooted submerged weeds 4ry amomia gas %*'!" ppm )* kg1ha -opper sulphate - %". ceretophyllum.*. @istia. etc. na9as.)'". ppm - 4ry ammonia gas *"'6" kg1ha ".%( detergent -do- .%'". 5 ygaster spp. hydrilla.spirodela lemna. -eratophyllum." ppm =not very affective at high p? ". :ubmerged weeds 7.* ppm ' :imazine 4iuron /arme Table !! -ommon weed eating fish and the weeds of their preference Fish s -ommon carp Kaurami Nam s -yprinus carpio 5sphronemus goramy Tender shoots F d upon Tender shoots of submerged weeds and filamentous algae Filamentous algae :ubmerged weeds e. @istia Aquous ammonia Anhydrous ammonia -do- ". etc. @otamogeton.* ppm ". -larias batrachus @untius spp.!'%. vallisneria. Algal blooms1mats -opper sulphate ' ".)'". W d 'ish .! kg1ha ". 5ttelia and duck weeds @earl spot Dtroplus suratensis Krass carp -tenopharyngodon idella :ilver carp ?ypophthalmichthys molitri Algal bloom Table !) -ommon predatory and weed fish of undrainable ponds (! dato!y 'ish -hanna spp. &. -do:ubmerged weeds =5ttelia. -dopotamogeton. azolla.g ?ydrilla .> 6.!( detergent - +. Dsomus danricus 5steobrama cotio 7. 2t kills all the fish species within a few hours when applied at the rate of !*" ppm =-2F82.?eteropneustes fossilis @angasius pangasius $ystus spp.! -pplication o' to4icants in ponds Mohua oilca6 7 5f all the fish poisons of plant origin.%.aubuca spp. bleachng powder and ammonia are considered suitable.east adverse effect on the pond biota To icity period should be of short duration :hould not have residual effect Dasy commercial availability :implicity of application -ost considerations. the most e tensively used fish to icant in undrainable ponds is oil cake of $ohua =<asia latifolia>. repeated netting should be done to ensure proper mi ing of the poison and .' &( of active ingredient. 7. which on dissolving in water haemolyses the red blood cells and thus kills the fish =<hatia. Following this operation. Amphipnous cuchia Kudusia chapra Amblypharyngodon mola .%. #allago attu Klossogobius giuris $astocembelus spp.!.!. $ohua oil cake.% Fish to4icants Although a number of chemicals and plant derivatives are available in the market which are poisonous for fish. • • • • • • • @oisoned fish should be safe for human consumption . The required quantity of mohua oilcake should be soaked in water and uniformly broadcast over the entire pond surface. 2t contains about . 5mpok spp. the saponia. %7&+>. only a limited number of such to icants are safe and suitable for fish culture purposes. <ased upon the following criteria a suitable fish poison is selected. %76">. 4isinfection of the pond is one of the essential measures for maintaining proper health condition of the fish. during storage. 2t kills all the predatory and weed fish of the pond when applied at the rate of !*')" ppm =Tripathy et al. it also controls the aquatic weeds and later acts as nitrogenous fertilizer.>. significant chlorine content is lost and hence it is always safer to use the commercially available bleaching powder at the rate of )*'*" ppm or )*"'*"" kg1ha1m of water. ! The method of application is also relatively simple. %7+*> and subsequently it serves as organic manure in the pond. 4istressed and dead fish are removed by netting. The to icity of doses up to !*" ppm lasts for about 7& hours =0hingran and @ullin. ?owever. it also satisfies the lime requirement of the pond soil.. Table !. 8ecommended doses of fish poison (oison <leaching powder $ohua oil cake Anhydrous ammonia @owdered seed of -roton tiqlium 8oot powder of $illetia pachycarpa :eed powder of $illetia piecidia :eed powder of <arrinqtonia acutanqula :eed meal of tamarind =Tamarindus indica> Dos 06g5ha5m2 )*" ' *"" ! *"" !" ' )" )" ' *" . -hlorine killed fish are safe for human consumption. -mmoniaF Anhydrous ammonia when applied at the rate of !"'!* ppm kills the predatory and weed fishes." ' *" %*" % 6*" '! """ . The powder is mi ed with water and uniformly spread over the entire water surface. 2t should be applied at least two weeks before stocking the ponds." ' *" . 9l aching po%d !7 <leaching powder or -alcium hypochlorite =-a5-l > is another practical and safe fish to icant. <esides. -hlorine content of the bleaching powder thoroughly disinfects the pond which is essential in undrainable ponds where disinfection by sun drying is not at all possible. <esides.removing the affected fishes which are suitable for human consumption. To icity of ammonia lasts for . 4etails of doses for commonly used fish to icants are summerised in the following table =Table !. Fish kill occurs within %') hours and the to icity lasts for )'* days.'& weeks. @lankton and benthic fauna start developing from the 6th or +th day after treatment. %7+">. Among beetles.accotrephes>. prey upon fish hatchlings and fry and also compete with them for food.# Calculation o' dos The required quantity of poison can be calculated using the following formulae. )&>. 4ragonfly nymphs are highly predatory on carp spawn. The common insect predators are beetles.!* ppm =active ingredient> for selective killing of the planktonic copepods.# &!adication o' p! dato!y ins cts $any aquatic insects in their larval and1or adult stages. water scavenger beetle =:ternolophus> and whirling beetle =Kyrinus> are more dangerous forms.2. %7+&>. giant water bug =<elostoma> and water stick insect =8anatra>. These copepods are predatory in nature and instead of serving as food for the delicate spawn and early fry.1. the pond should be treated with malathion at the rate of ". diving beetle =-ybister>. @roper prepration of nursery ponds for stocking with spawn thus also aims at total eradication of such predatory insects.1. :uch treatment is not required in rearing and stocking ponds. bugs and dragonfly nymphs =Fig. 5ther predatory members of this group are water scorpion =. The basic method is to apply a thin oily film over the pond surface which chokes the respiratory tubes of aquatic insects. This treatment significantly increases the survival in nursery ponds =/umar et al. <ack swimmers =Anisops> appear in swarms in manured ponds during rainy season and cause heavy damage.. H. they attack and prey upon them resulting in poor survival. For rectangular pondsF T 8equired amount of poison in kg. H.Tea seed cake =-amellia sinensis>N N 8equires additional dose of lime at the rate of %*" kg1ha 6*" The nursery ponds require subsequent poisoning for selective killing of the larger planktonic copepods. For this reason . The spawn and fish .'* days prior to stocking of spawn. For circular pondsF T 8equired amount of poison in kg. $D.$D.2FD8AT25.4 -AA:D :T8D:: T5 F2:? <DTTD8 D.food organisms remain unaffected.E285. Table 25 Pond treatment methods for eradication of predatory a !atic insects Treatment method :oap oil emulsion 4iesel oil /erosene oil Turpentine oil 4iesel emulsifier Dose/ha *& kg vegetable oil L %+ kg soap *" ' &" % +" ' %"" % 6* % 4iesel *" % N emulsifier )6.T RA2-/ @85.* ml L water ! %.T FAE5A8: F2:? @8DED. . A. :ome of the common treatment methods are presented in the following table =Table !*>. A4ED8:D D.2FD8AT25.T FAE5A8: @AT?5KD.E285. @85. T2.T 2. D.TD8A-25.E285.T2. 2t is the film of the emulsion which is .ursery @ond D cept for soap-oil emulsion other mi tures or emulsion are easily prepared by simple mi ing. For making soap-oil emulsion. These emulsions are applied by spraying over the pond surface about %!'!.E285. Figure )&.$D. 8D:A.E28A.T2. C.TD8A-T25.?5:T @AT?5KD.T @AT?5KD.$D.K 2.D ?5:T AD-A4ED8:D ?5:T @ . hours prior to stocking of spawn. -ommon 2nsect @redators in . D.5 42:DA:DB -5.D. the soap is mi ed with oil and gently heated for some time with vigorous stirring.K 42:DA:D-5AT<8DA/ ?-:A:-D@T2<.42T25.: 8D:A. ?5:T @AT?5KD. Although. p? of soil is also one of the critical factors affecting pond productivity. 2mportant characteristics of pond soil which influence fertilizer use is briefly described here. the nutrients from the water are trapped. Ander anaerobic condition the decomposition of organic matter is slow and the products of decompositions are mainly reduced compounds and short chain fatty acids thus making the soil strongly acidic. nitrogen. #indy days should be avoided as it will break the film. Availability of essential mineral nutrients such as phosphate.1. on the other hand are low in colloidal substances and also deficient in organic humus. basically influences the economy of both inherent and added nutrients.1 9asis o' ' !tili=ation 2n undrainable ponds where the frequent change of water is a remote possibility. due to high adsorption capacity.important and hence care is taken not to disturb the film for a few hours. phosphorus is required in a small quantity compared to . /oil pH7 As in water. <oth for soil and water a slightly alkaline p? is considered favourable for fish ponds. :andy soils. the physico-chemical properties of pond water governing the biological production cycle are more or less a reflection of the bottom soil. H. ?owever.the living fertilizer factory of the pond. mechanical composition of the soil comprising sand.e. potassium. H.). T 4tu! o' th soil7 The te ture of pond soil. carbon and calcium is a consideration which determines the quality and quantity of fertilizers to be applied.itrogen is required in large quantities as it is the basic and primary constituent of protein and chlorophyll. The organic and mineral constituents of the soil play their part in releasing the required nutrients into water for pond productivity through chemical1biological processes. . These are important considerations for deciding the application of fertilizers and manures. @ond bottom soil also provides suitable substrates and necessary environment for the microbial decomposers . :oil p? also influences transformation of phosphorus into available forms and controls the adsorption and release of essential nutrients at the soil-water interface. Thus it is the soil condition and its nutrient status that forms the basis of pond fertilization by using either organic manure or inorganic fertilizer or a combination of both.) F !tili=ation o' ponds Fertilization schedule involving both organic and inorganic fertilizers starts %"'%* days prior to stocking and is prepared on the basis of nutrient status and chemical environment of the pond soil and water. if swarms of these predatory insects are seen in the nursery pond. :andy and very clayey soil are not desirable as in the former the nutrients are lost due to heavy leachingG while in the latter. -lay minerals and organic matter of the bottom mud are both colloidal in nature and thus e hibit colloidal properties like adsorption and cation e change phenomenon.1. silt and clay and organic matter content. i. $alathion application in nursery ponds also controls the predatory insects population and hence subsequent treatment for control of insect is not required. treatment should be applied immediately. 0mg51FFF g soil O!ganic ca!3on 0B2 *" or more !* ' .ess than !* $iming7 4iurnal changes in p? values ranging from p? * during the night and p? %% during the day due to community respiration and photo-synthesis is a common e perience but such wide variations impose stressful conditions for the fish. .iming helps to raise the total alkalinity level and consequently the reserve -5 ! will increase the availability of carbon for photosynthesis by raising the bicarbonate concentration in water.)>.ess than ". Table !& . . This raised level of reserve -5! will also prevent biological decalcification.* . 4etailed recommendations have been made in the chapter on pond environmental monitoring =:ection 7. H.utrient status of high.& ' 6. .). it is considered as the single critical element for maintaining aquatic productivity.1.* <elow *.* N0mg51FFF g soil2 (2O. An adequate level of calcium in the pond provides a buffering system as shown in Figure )6.2 F !tili=ation sch dul @roper analysis of soil and water is essential before deciding on the fertilization schedule. <aner9ee =%7&6> classified the undrainable ponds into low.). on the basis of their nutrient status considering mainly nitrogen.* *.* ' %. medium and highly productive groups. phosphate and organic carbon =Table !&>.ow pH &.* or more ".* ' &.nitrogen.ess than ) %. medium and low productive ponds -*aila3l nut!i nts (!oducti*ity l * l ?igh $edium ..7 & ' %! )'* . Figure )6. Alkalinity can also be used as an indicator of the need for lime in fish ponds.ine 4epending on the p? of the soil. the dose of the liming should be Ad9usted as per the following table =Table !6>. additional doses of lime can also be applied. ?owever. The total dose of lime calculated as per the table. $echanism of <uffering Action of . as and when needed during the culture period. rearing and stocking ponds. . doses and the first dose may be applied about a week prior to the manuring of the pond. The same dose is applicable for nursery. 2t helps in faster mineralisation of organic matter in the pond sediment and acts as a prophylactic agent as well. need not be applied at one time. 2t may be divided into )'. +.* /oil typ ?ighly acidic $oderately acidic ..itrogenous fertilizers are selected on the basis of soil p?. 2f the pond is poisoned by mahua oil cake. .7 *.'* instalments. use of mineral fertilizers is not recommended as the application may cause blooms of algae which may persist and may harm the young fry. 2n case of poultry manure the dose should be only ))( of the cattle dung. A combination of organic manures and inorganic fertilizers is considered more effective than using either of these alone. The monthly instalments of organic and inorganic fertilizers are applied alternately allowing a gap of a fortnight between the two applications.* ' 6. The rate of application is between * """ ' 6 """ kg1ha in * instalments. ?owever. then the pond should be fertilized with ! """ kg1ha of cattle dung about a week before each subsequent stocking. 2f two or more crops of fry are to be produced during the season from the same nursery ponds.. Table !+ Amount of fertilizers required for ponds having .il R "ui! m nt o' lim 06g5ha2 Manu!ing7 5rganic manuring besides being important as means of adding the nutrients. the initial manuring is not essential.* ' +." ' &.* ' 7. if mohua oil cake is applied earlier... The total quantity of inorganic fertilizers to be applied is decided according to soil type =Table !+> and applied in equal monthly instalments. 8earing ponds are initially manured with the raw cattle dung about two weeks prior to stocking. is also equally important for improving the soil te ture. 6. 2n the absence of soil testing facilities a general recommendation should be followed.ear neutral $ildly alkaline ?ighly alkaline ! """ % """ *"" !"" ." ' .Table !6 8equirement of lime for different types of pond soils /oil pH . 2n stocking ponds a combination of organic and inorganic fertilizers is considered more effective. in nursery ponds. 4ose of inorganic fertilizers may be regulated as per pond soil productivity determined by detailed analyses. 2n such cases inorganic fertilizers are applied at the rate of urea %.. then the dose should be restricted to * """ kg1ha. ?owever. 2f the pond is treated with mohua oil cake then the dose of organic manuring is reduced to half. -ow dung at an initial dose of %" """ kg1ha may be applied in the nursery ponds about two weeks prior to anticipated stocking." kg1ha and triple superphosphate &" kg1ha in . &. 2nitial manuring with organic manure at the rate of !"( of the total requirement is done %* days prior to stocking and the remaining +"( of the organic manure is applied in %% equUl monthly instalments during the rearing period. "'.2 /toc6ing . :ingle super phosphate or Triple super phosphate Iuantity 06g5ha2 ! """ % """ !* )" )" !" + ( !iodicity o' application 2nitial dose $onthly $onthly $onthly $onthly $onthly $onthly H.*> or -alcium ammonium nitrate =p? *.high.*> -.*(> * """'+ """ %%!'%** !!*'))" %*&'!%7 *.*(> -alcium ammonium nitrate =!".)'.*'&.*'6."* %%%'%.'6* + """'%" """ %*&'!!* )*"'*"" !!"')%* 6&'%%" %" """'!* """ !!&'!&" *"%'&*" )%&'.*(> :ingle super phosphate =%&'!"(> Triple super phosphate =. -attle dung -attle dung <. medium and low levels of productivity (ond p!oducti*ity l * ls High 8ate of application of fertilizer =kg1hg1y> -attle dung Area =.*> or Ammonium sulphate =p? above 6.*(> Ammonium sulphate =!". Table !7 Keneralized fertilization schedule for stocking ponds =-2F82. %7+*> It m A. Area =p? &.* M dium $o% 2n the absence of proper soil testing facilities fertilization schedule in stocking ponds may be followed as per the following table =Table !7>. At higher stocking density the growth is relatively slow.& &!. 2t is possible to raise )'.! !..2.1 /toc6ing o' nu!s !y ponds -arp spawn requires natural feed immediately after stocking and hence it is essential to have a minimum plankton value of )"'. Table )" :urvival of carp fry at various stocking densities /u!*i*al l * l 0B2 +6. :pawn are reared in nursery ponds up to fry stage for about !') weeks when they usually attain !').'& million1ha. the pond can also be utilized for rearing of common carp seed during 0anuary to $arch.6* g in weight.!* %". a hapa should be fi ed in the pond and some stocking materials should be put inside the hapa. The rate of stocking in a well prepared nursery pond with adequate fish food organisms can be as high as %" million1ha.) 6. H. The stocking density must be according to the condition of the pond and the amount of fish food organisms available. the survival level decreases with the increase in stocking density =:en. the plankton volume should be around %"" ml1m . crops of fry from the same pond during the same breeding season and in addition. Absence of distress and mortality after !. 5ne or two days prior to stocking. The pond should be stocked after three days of hatching when their sizes range from "." ml1m in case of stocking at a moderate rate =%.%*'". plankton population is also required to be increased accordingly. ?owever. #hen a higher stocking rate is to be adopted.&' ". 2n case the stocking density is over * million1ha. %76&>.*' !. rearing and stocking ponds.* million1ha>.* cm in length and ".6* &. ) ) :elf-produced or procured )'. hours confirm complete deto ification and the pond should be regarded as ready for stocking.6* cm and counts on an average about *"" numbers1ml.-omplete deto ification of the piscicide applied earlier should be ensured before stocking the nursery. =Table )">.* )." &&. The required number of spawn are measured with the help of metallic or plastic sieve cups of known volume."" /toc6ing d nsity 0million5ha2 -ombined rearing of two or more species of spawn should not be done in nursery ponds. . days old spawn should be stocked in the morning at the rate of . common carp =." g in weight. viz. common carp. catla =-atla catla>. rohu. etc.F%F)>G silver carp. For healthy fry rearing it is recommended that the size of the fry at the time of stocking in the rearing pond should be as uniform as possible.catla. the pond can also be stocked with advanced fry or early fingerlings in absolutely predator-free ponds. mrigal.2. Dither monoculture or polyculture methods can be adopted for this rearing. rohu =)F%. are also matters for consideration. 2n the case of polyculture the species combination and their ratio should be decided on the basis of their habit. :ome of the possible combinations are .2 /toc6ing o' ! a!ing ponds 8earing of fry to fingerling stage is done in rearing ponds where fry are stocked at the rate of ". common carp =)F.F)F)>G catla.* m should be stocked at the rate of * """ fingerlings1ha. availability of feed. ) Table )% 4ifferent species combinations and their stocking ratios for composite fish culture /p ci s com3ination /u!'ac ' d ! Column ' d ! Rohu 9ottom ' d ! Mac!ophyt ' d ! +!ass ca!p Catla /il* ! ca!p M!igal Common ca!p .!*'".H. Ruality of available natural fish food in the pond and the capacity of the farmer to provide supplementary feed. rohu =.2.*>G silver carp. grass carp =-tenopharyngodon idella> and common carp =-yprinus carpio> is considered to be the ideal combination. @rior to stocking the rearing ponds the pond waters must have a plankton level of about )"'*" ml1m . 2n composite fish culture. three or four species combinations can also be taken up. Asually a pond having average water depth of %. ?owever. ) H. Fry are reared in ponds for about ) months when they usually attain %""'%*" mm in length and %*' . etc. ?owever.*'!. rearing of si species of carps. 8atio of different species in the combination is also equally important. The volume of water available for fish in an undrainable pond should not be less than ! m 1fish if there is no provision of artificial aeration. mrigal. The stocking rate depends primarily upon the volume of water and on the o ygen balance of the pond. grass carp =. This can be done by size grading at the time of fry harvesting from nursery ponds. 2n case the fingerlings are not available.abeo rohita>. silver carp =?ypophthalmichthys molitri >.F)F%.*F)>. grass carp =%F%>G silver carp.)" million1ha with a survival level of &"'+"( under proper pond conditions. grass carp.*F!. feeding. the pond should be stocked with %""'%*" mm long fingerlings of desired carp species. rohu. grass carp. -ombination of too many species should be avoided as it invites e cessive handling at the time of harvesting for species segregation.# /toc6ing o' g!o%:out5stoc6ing ponds After proper preparation. depending on the availability of quality fingerlings of these carp species. there are certain general guidelines for selecting species combinations =Table )%>. mrigal=-irrhinus mrigala>. fry and fingerlings should be done very carefully to avoid any poststocking mortality due to shock or infections. :ilver carp." %"'%* !"')" %*'!" !"'!* %*'!" !"'!* N . Therefore. .).1 F ding :oon after stocking. 2n older ponds where the soft sediment layer of the pond bottom is usually very thick and anaerobic in nature. <ased on the performance of individual species in the combination and availability of seed. combinations can be modified in subsequent years.# (ost:stoc6ing manag m nt @ost-stocking management involves harnessing the pond productivity in the form of natural fish food. :pawn feeds voraciously on plankton. the relative density of column feeder-rohu should be kept on the high side in deeper ponds than in shallower ponds. To minimize post-stocking mortality the fry1fingerlings should be slowly and gradually acclimatized to the temperature and quality of the water in the stocking pond. open the mouth of the seed transport bag1container and gradually add the pond water in phases and after %*'!" minutes slowly dip and tilt the bag1container in the pond so that the spawn1fry1fingerlings are free to swim out.. supplementary feed is broadcoast on the pond surface in the form of fine powder daily in the morning hours at prescribed rates =Table )!>. 2n the case of nursery ponds where spawn are reared for about a fortnight up to fry stage.2.>. the fish start grazing natural food available in the pond irrespective of their stage of life cycle. maintenance of pond environment congenial to the cultivated fish and fish husandry. H. ) H.#. The stocking pond also should have a desired level of plankton population of about )"'*" ml1m . the ratio of bottom feeder and especially the common carp should be kept at a higher level.) M thod o' stoc6ing :tocking of spawn." - )" !"')"N %*')"N )" - *'%* )"'. To do so. 2nterspecies competition for food between catla and silver carp to some e tent is the key point for such differential stocking. H. should be stocked % or ! months later. immediate steps must be taken for providing supplementary feed.ikewise. whereas ponds showing consistently higher zooplankton population should have a higher ratio of surface feeders. however.) . Apply prophylactic treatment to seed prior to their release so as to avoid any post-stocking infections =:ection 7. mainly feeding and health care. :tocking should preferably be done in the cool evening hours.ower units in shallow ponds Availability of weed in the pond or in the vicinity decides the stocking density of grass carp. & . . -eratophyllum." ' F d :oft macrophytes such as Azolla. :ee Fig.6 ' ).o feed ?arvesting *&" g1day & ' %! %) %. Table ). % %!" g1day - At the time of stocking. in addition to those . ?ydrilla. g each.1 million o' spa%n .. the spawn of "." g. .% million weigh about %. -hara. Krass carp is fed its preferred aquatic vegetation or green animal fodder as per the following table =Table ). etc. and a mi ed collection of ".&*'".""%. Eallisneria.emna and :pirodella.6* cm average length weigh about ".a9as..7 cm> Fingerlings =. Feed for grass carp during various stages of life cycle /tag Fry =%. )+.>. . Table )) Feeding schedule for nursery ponds ( !iod 0Day '!om th dat o' stoc6ing2 %'* Rat o' ' ding -mount o' ' d 'o! F. etc. #olffia.Table )! 8ates of daily supplementary feeding at various stages of culture /tag :pawn to fry Fry to fingerlings Krowers <rood fish Daily ' . times the total initial weight + times the total initial weight .'+ times of the initial body weight *"'%""( of the initial body weight % ' !( % ' )( ding !at The following schedule of feeding should be followed for nursery ponds =Table ))>. ))<>. Figure )+. but both types should be water stable. total standing crop and amount of feed to be given should be estimated on the basis of data thus available. the average weight of each species should be recorded =Table )*>. . monthly increment in weight. The sinking type of pellets are put in feeding trays fi ed in the pond." cm> 0uveniles1Adults =above %*. the supplementary feed mi ture should be mi ed with enough water to make a dough and applied into feeding trays fi ed in the ponds. stocking and brood stock ponds. etc.%*. 2n the case of rearing. @eriodical netting should be done strictly on a monthly basis and with the help of hand nets and spring balance =Fig. Feeding Dnclosure for Krass -arp The form in which the supplementary feed is given is also important. )7>. drumstick. The average weight of individual species. The standing crop of fish is estimated every month on the basis of sample netting for growth and health check and feeding schedule is ad9usted accordingly. green animal fodder such as barseem. tender leaves of vegetables and trees such as soobabul. The pellets may be of the sinking or floating type. hybrid napier. napier. <etter results can be obtained if the feed mi ture is pelletized and fed to fish =Fig. 2n addition to above. 2n the nursery ponds the feed should be provided in finely powdered form and may be broadcast over the pond surface. elephant grass." cm> mentioned above. **"" . o' Total this last g!o%th 'ish stimat d month0g2 month0g2 0g2 stoc6 d c!op 06g2 *"""" *"*"" *"""" .""" %+.Average weight H.The feeding tray should be cleaned daily before the application of fresh feed. . Krass carp should be fed until they stop eating." %*" !"" !"" %*" %&&. %t.*+. )"" *+" %"" .. Fish normally stop feeding if they are sick or the temperature is far below normal. o' 1F 'ish 0g2 2 # 0/ampl s2 -atla 8ohu $rigal :ilver carp Krass carp %%""" %%""" %%*"" %%!*" %%6*" % %%" &""" 6""" 6*"" 6""" 6*"" 6"" 7""" 7*"" 7""" 7*"" 7%"" 7!! !!""" !!6*" !!*"" !!*"" !!!*" ! !. o' -*. adequate o ygen. about *"( of their body weight on a daily basis.2 ( !iodic ' !tili=ation The ne t step in post-stocking management is the periodic fertilization which ensures replenishment of nutrients and consolidation of the energy base for microbial decomposition activities."" ))&.+""" ." % "!* &*" +*" ! """ +* *" 6! !. %t. 2n such situations a proper health check is required and the feeding rate is ad9usted. -*.""" ) . Table )* 4ata sheet for monthly netting /p ci s stoc6 d 1 -*.. sequence and timing of application of fertilizers are important or achieving best results.&.ime should be applied first followed by the organic manure and finally the inorganic fertilizers an the same order is followed subsequently. %t.*"" %.& kg Amount of feed to be applied daily at the rate of !( body weight Av. Asually they consume aquatic vegetation."" %*)%. These fertilizers should be applied only when the physical conditions of the water are most suitable such as plenty of sunlight. The desired total quantity of fertilizers are best applied in small equal doses at periodical instalments throughout the rearing period so as to ensure ma imum utilization of these fertilizers. . optimum temperature. adequate water level and low . ++" .#. The mode. o' Monthly No.""" -ommon %!""" %!&"" %!""" %!*"" %!*"" % !)! carp Dstimated total standing crop % %*" +! !"" !..)"" )".". wt. Fertilizer should be sprayed or distributed properly over the water surface during the day time when the top layer of water is warmer and lighter.* ppm or above at any stage during the periodic pond environment monitoring. :imilarly. organic manuring may also be stopped if the soil organic carbon level goes beyond !(. The results are encouraging when organic manures are applied in daily doses in pons. 2norganic fertilizer application must be stopped temporarily when the nitrate and phosphate content of water show a level of ". 2n nursery ponds the first manuring is done two weeks prior to stocking and if more than one crop is nursed. fresh manuring should be done a week prior to every subsequent stocking. -are should be taken to see that the phosphatic fertilizers dissolve properly in the water since powdered orgranular fertilizer may often solidify after coming in contact with water.wind velocity. normal application may be resumed after the specific nutrient level goes down. 2t is more effective if doses are divided further so that application is more frequent. ?owever. Turbid water with a high content of suspended solids are not preferred. The desired amount of cattle dung is mi ed with water and uniformly spread over the entire pond surface. . ?and .Figure )7.%.!>.). Table )& @eriodicity of fertilization in nursery.et and :pring <alance A periodical fertilization schedule is summarized in Table )&.ursery ponds 5rganic manure Manu! ( !iodicity ) weeks . rearing and stocking ponds (onds . The rate of fertilization by organic and inorganic manures has already been discussed =para 7. The fish farmer should also monitor the following parameters on a routine basis.daily $onthly H.# (ond n*i!onm ntal monito!ing H. This necessitates periodical monitoring of pond environment and taking corrective measures in time. details of culture activities. 5lah and :inha =%7+. stocking structure and density. .#. harvesting. -g 7 Age is one of the most important parameters. The system needs simple instrumentation. rearing pond or stocking pond. feeding. $ost of these parameters can be easily measured at the pond site while some require laboratory facilities. marketing.2 (a!am t !s to 3 monito! d 2t is essential for e tension workers to name and code-number the ponds in their area. To obtain qualified data on the organic carbon and biogenic nutrient load it is necessary to know the number of livestock and human population associated with the particular pond. The species of fish present.8earing ponds :tocking ponds 5rganic manure and 2norganic fertilizer 5rganic manure and 2norganic fertilizer ) weeks . This can be done easily with the help of a bamboo pole of known length.1 + n !al consid !ations @roper pond management involves a regular and steady supply of nutrient for sustained production of fish food organisms. etc. H. The fish farmer should record the following information on his fish farmF Natu! o' pond7 @erennial or seasonalG nursery pond. since it has direct relevance with the productivity of the pond which usually varies from one year to several hundred years. fertilization. Wat ! a! a7 $easurement of the water area is essential in order to know the size of the pond for proper fish stocking and quantifying the production processes.#. 2t is also required to regulate the physico-chemical parameters of the pond ecosystem within the safe tolerance limits of the cultured fish species. etc. need to be recorded. Manag m nt7 $anagement status should record the e isting management techniques and its level =intensive or e tensive>. little working time and labour and reveals sufficient information about the actual nutrient level of pond sediment and water.#. The supply of nutrients could be from within the pond itself or from outside.#. :uch coding may be based either on postal district1unit1village farmer3s name. The monitoring system gives reliable guidelines for fish farmers to optimize fish production.#.> have developed a practical monitoring system of perennial undrainable ponds which offer the monitoring of basic architecture and production processes of such pond ecosystems in tropical monsoon lands. and @5. :uch thick sediment. . The thickness of the layer can be measured with a &'+ m long bamboo pole with a sharp end. a low transparency may result either from high turbidity alone or from dense algal population and thus cannot reflect the correct trophic or production level of the water. having a rich nutrient content. alkalinity.ormally the p? and alkalinity do not change from pond to pond on the same types of maternal soil. in addition to the soft sediment layer.-.-@ indicate the basic inorganic nutrient status of the pond.Wat ! colou!7 The visual colour of the pond water is a simple but important reflection of the basic production processes. The measurements of . Da%n o4yg n7 Fish ponds usually e hibit wide fluctuations in the dissolved o ygen content from day to night.?.. Ch mical n*i!onm nt in th %at ! column7 The water is chemically characterized by p?. . the :ecchi transparency readings together with the visual colour provide valuable information on the productivity of the water. 4esirable ranges of various pond environment parameters are presented in Table )6. The total thickness of the soft plus solid sediment layers has a direct relation to the age of the fish pond.3 :imple chemical parameters such as dissolved o ygen and p? may be measured using field kits. ?owever. After the rainy season the water level gradually decreases which results in a very shallow water column by the end of the dry season. Wat ! t!anspa! ncy7 #ater transparency measured with a :ecchi disc is intended to quantify the result of those processes which determine and modify the visual colour.?. This should be properly utilized for fish culture. A single measurement 9ust before sunrise would be an important indicator of the risk of fish kill due to o ygen depletion. /olid s dim nt d pth7 2n older ponds. This diurnal o ygen fluctuation is normally measured to calculate the community metabolism of the whole pond while quantifying the production and respiration processes in the ecosystem. The water depth can be measured with a . /o't s dim nt d pth7 A soft sediment layer is usually present in the pond bottom.-5)-. at times the sediment layer measures more than ! m.*> and o ygen levels of &'7 ppm indicate optimum condition."'+. :lightly alkaline water =p? 6. and @5. . ?owever. ..'* m long bamboo pole fitted at its base with a wooden disc of !* cm dia. is anaerobic in nature with slow bacterial decomposition and mineral cycling rates.5). a solid sediment layer with a low water content is also present. The depth of this layer can be measured with a &'+ m long bamboo pole having a wooden disc of %" cm dia at its base. Table )6 4esirable ranges of pond water quality parameters (a!am t !s #ater colour D si!a3l !ang Kreenish brown .-@ measurements following standard methods. Wat ! d pth7 The primary water source is usually the rainfall during the monsoon.-. ?.! ppm ".5)-.! ppm A simple schedule for monitoring the important parameters is presented in Table )+. Wat ! #ater colour Transparency Temperature 4epth p? Free -5! AlkalinityF Total <icarbonate 4awn 4issolved 5! . ." ' +.Transparency p? 4issolved o ygen Free carbon dio ide 2norganic nitrogen 2norganic phosphorus !* ' *" cm 6." ppm ". - Daily W 6ly Fo!tnightly Monthly Iua!t !ly . Table )+ Dnvironmental monitoring schedule ( !iodicity (a!am t !s A.* *.-." ppm %*. the characteristic pathogens flourish. The fish itself possess a varied and comple defense system. Thus a disease outbreak may often be a symptom of environmental imbalance and it gives a distress signal so that the adverse environmental conditions may immediately be corrected to prevent fish losses. <y resolving environmental problems and applying effective therapeutics.). . when present in the surrounding.#. /oil :ediment depth p? 5rganic carbon Total nitrogen Total @5. %76. Ander such circumstances if the fish fail to ad9ust adequately or if corrective measures are not taken timely.) Fish h alth monito!ing 2n most of the situations. $ost of the fish disease agents belong to this category. cultured fish are healthy even in the continuous presence of pathogens. ?owever.@5. :ome of the infectious and parasitic agents can survive only in live fish.>. the immune system. The approach to health care in composite fish culture in undrainable ponds is essentially one of management of ecosystem and fish husbandry.-@ - - - - - - - - H. when environmental stresses occur and the balance shifts in favour of the disease. and in such cases the disease transmission is from fish to fish.#. 5thers are e tremely adaptable organisms which can survive outside the fish and cause infections whenever fish are weakened or otherwise predisposed to disease due to environmental stress. outbreak of diseases may occur. A virulent pathogen. the original balance between the host and the pathogen may be restored. :uch disease-producing agents are true pathogens.1 Host:pathog n: n*i!onm nt lin6ag :usceptible fish.">. the virulent pathogen and the aquatic environment in which they encounter each other are the three contributing factors in fish disease outbreaks =:nieszko. The causative agents of the disease and their fish hosts carry on their struggle in the aquatic environment and the environmental parameters which influence this encounter may shift the balance from one side to the other and often determine whether the host will overcome the infection or the pathogen will flourish =Fig. the potency of which determines the susceptibility or resistance to the particular pathogen under a particular circumstance.-@ <. H. :everal environmental components effectively influence the normal immune mechansim of the fish when their value e ceeds the normal tolerance limits. . is usually capable of causing an infectious disease to fish under stress. iv. A fish health monitoring programme should consist of the following componentsF i. in advanced stages of the disease.H.#. control and treatment measures do not provide economical and effective. ii.). disease outbreak or mortality. . $onitoring of pond quality and sanitation. :ampling and e amination of fish at regular intervals for health check and diagnosis of the disease if any.2 H alth monito!ing p!og!amm ?ealth protection of cultured fish is considered to be one of the most important aspects of modern aquaculture systems including the composite fish culture which requires a programme basically to check the health status of the fish quite frequently and employment of fish health management measures. 4aily observation of fish in each pond. iii. 5therwise. This enables timely detection of any disease outbreak and taking up proper treatment measures at the initial stage. :ampling and e amination of fish at the onset of distress. A thorough health check of fry1fingerlings is required % or ! weeks before netting out for stocking in grow-out ponds or before transfer to another pond. Dffects of Dnvironmental -hanges on Fish-@athogen 8elationship The sampling for health check of fry and fingerlings should be done at weekly and fortnightly intervals respectively. :uch an e amination will provide sufficient info rmation for planning. while in composite fish culture ponds it should be at least once a month.". the most common of those are listed belowF . 4iseased fish may e hibit either or both physical and behavioural signs.Figure . freshly dead specimens may also be collected for laboratory e amination. Table )7 $ethods for diagnosis of commonly occurring diseases of Asiatic carps in undrainable ponds Dis as ag nt -. pathoanatomical and microscopical studies of squash and smear preparation from different organs1tissues. swimming erratically or in spiralsG surfacing for gulping air and scraping against the floor and sides of the pond.G decolouration or paling of gillsG abdominal swellingG bulging of eyesG presence of cysts. only those specimens e hibiting symptoms of distress or disease should be selected. haemorrhagic spots and greyish or brownish areas over the body.9 ha*iou!al signs7 • • • slowing down or a complete stoppage of feedingG loss of equilibrium. . Clinical symptoms7 • • • • • • • • e cess mucous secretionG change in normal colourationG erosion of scales. etc. etc. $a3o!ato!y 4aminations7 Thorough visual e amination for e ternal signs of the disease should be followed by detialed but quick laboratory e amination by pathomorphologica. but if necessary.ive moribund speciments are preferred. part of fins.G appearance of lesions. (a!asit s %. @rotozoa M thod o' 4amination (ositi* indications . skin. spots or patches over the body and gills. 4iagnostic procedures in brief are presented below =Table )7>. 2n situations where a disease problem is suspected. lesions over the body and microscopy presence of parasites attached to fish body by means of suckers and hooks. :mall pigmented black nodules over the body surface 9. -rustaceans Arqulus Eisual e aminations1 ?aemorrhagic spots. -ottony outgrowths of fungal mycelium over the infected area. <ranchiomyces $icroscopy ). 9act !ia %. Fungi %. Appearance of e ternal lesions on the body. :aproleqnia $icroscopy 1visual e amination <ody lesions associated with small white tufts of hyphae on fins and skin. @resence of saucer-shaped actively moving ciliate parasites on body surface and gills.esions initially begin as whitish or brownish patches with reddish zone around the periphery. Trichodina $icroscopy $y ozoans $icroscopy !. @resence of ciliated trophozoites with relatively large horseshoe shaped nucleus. air-bladder. Flukes Kyrodactylus14actyloqyrus $icroscopy 4iplostomum Eisual e amination1 microscopy @resence of parasites in gills and skin. etc.2chthyophthirius $icroscopy @in-head size white spots on the skin. . Achlya $icroscopy C. -linical condition is usually indistinguishable from that of aeromonas. !. fins and gills. 2nfected fish eggs fail to hatch and show presence of fungus mycelium protruding from the egg surface. Aeromonas hydro. ?aemorrhages over the body. @seudomonasfluodrescens -ulture1microscopy ). spleen. body surface and1or in the squash preparations of kidney.phila -ulture1microscopy 4ropsy condition and haemorrhages over the body. spores on gills. erosion of lamellae and presence of fungal hyphae in blood vessels. !. ). 4ecolouration of gills. head region and gill. @resence of cysts. Fle ibacter columnaris -ulture1microscopy . employing aseptic techniques.. /u!* illanc and maint nanc o' %at ! "uality7 Abrupt and wider fluctuations in some of the environmental parameters such as dissolved o ygen content. specimens may be forwarded packed in ice. 8habdovirus of common carp -ell culture1serum neutralization test -ommon carp is prone to this disease showing dropsy condition.. . :lides can then be dired. and to ensure this the knowledge of the role of various environmental components in the occurrence of disease outbreak is essential.%>. The following important measures are the key components of successful fish health managements =Figure . <acteriological media can be inoculated with materials from various organs. often cause stress in fish and predispose them to infectious diseases.D. heart.#. accurate diagnosis of disease is of utmost importance if proper treatment is to be applied and this is possible only through e perience and training.. p?.i!us %. etc. etc. %7+!>. pesticides and naturlaly produced to ic substances such as hydrogen sulfide. et al. The volume of fi ative should be at least five times the volume of materials to be preserved. Anything that alters the . especially kidney. The main thrust of such measures is directed towardF • • • • minimizing the stress on cultured fishG prevention of the introduction of serious disease agentsG confinement of disease outbreaks to affected areasG minimizing losses from disease outbreaks. 2n case of larger specimens incision may be made to facilitate effective penetration of the fi ative. detergents.# ?ealth management measures Anderstanding and managing the undrainable pond environment is the key to successful fish health management and profitable fish culture. !. As far as possible the specimen for e amination to reference laboratories should be always sent live but when circumstances prohibit live delivery. 5n-site disease diagnosis permits the immediate application of chemotherapy or remedial measures to control or eradicate the disease. ?owever. may disease conditions occur which cannot be properly diagnosed without specialized laboratory facilities and in such conditions samples should be sent to such laboratories under proper preservation. packing and shipment =4ey. 8habdovirus of grass carp -ell culture1serum neutralization test :mear preparation of selected tissues and organs may be made on the spot by smearing the material on a slide. H.). :pecimens for parasitology e aminations may be preserved in *'%"( formalin solution. additions of some chemicals. At times. ammonia. dinoflagellate to ins. 5nly grass carp is prone to this disease e hibiting similar dropsy symptoms. temperature. turbidity. stained and e amined immediately. resulting in the appearance of bacterial bloom and related o ygen depletion =8adheyshyam et al. ?owever. bottom raking. @roper and timely management of soil and water qualities by manipulating feeding. etc. increased feeding and fertilization programmes resulting in nutrient accumulation leading to appearance of algal blooms that lead to dissolved o ygen and other water quality problems. At lower levels of dissolved o ygen." mg1% indicates organic pollution. For health and optimum growth. aeration of water by recirculation or splahsing. fish will be under stress and may not grow well.* or below &. Ammonia concentration above %. -arbon dio ide concentration up to !"')" mg1l may be tolerated by fish provided o ygen is near saturation. $aking the pond environment more congenial and hygienic. the recent trends of intensification in aquaculture involve high stocking rates. . to icity of carbon dio ide increases.iming agents may be used for low p? corrections. 2n older ponds. liming. Andrainable ponds offer great protection against spreading of disease outbreaks by confining the outbreaks only to the affected ponds. . addition of clean water. An interval of about %* days between the pond poisoning and the stocking eliminates most of the pathogens from the environment. ?ydrogen sulfide to icity increases with decreasing p? and it is harmful even at %.environment of the fish is a potential stressor and efforts should be made to identify and avoid them. fertilization." mg1l concentration level. eliminates the risk of stress and provides safety to fish.. reduces most of the environmental problems and provides congenial conditions for the health growth of fish. the dissolved o ygen level should not drop below * mg1%.. #hen p? values remain above 7." for e tended periods.>. cases of e cessive accumulation of organic matter have been observed. and hence it is advisable to follow the recommended stocking density for nursery. the stocking materials should also be prophylactically treated before releasing into the pond =detailed under -hemoprophyla is>.Figure . deterioration of water quality.%. depletion of dissolved o ygen. rearing and stocking ponds. 5verstocking may lead to biological crowding resulting in waste build up.. samples of the stocking material should be e amined to check their health status. decreased availability of natural food. A $odel for 2ntegrated Fish ?ealth $anagement :ystem 2t is always advisable to stock the pond only with healthy and genetically vigorous fry and fingerlings so that they may have better growth rate and resistance towards diseases. . etc. @rior to stocking. ?owever. This avoids any risk of introducing infected stock in the pond. nets and gears. These copepods prey upon young fish larvae and also serve as vectors or carriers of many infectious pathogenic organisms.#ild fish population is one of the most potential sources of diseaseproducing organisms. ?igh temperature during hot water causes increased metabolic activity and induces more stress upon them. Any deficiency in quantity and quality of feed may cause various diseases by increasing susceptibility to many infections. %7+&>. @roper feeding . tadpoles.Minimi=ing handling st! ss7 The rougher the handling. @ond embankments may also be raised to prevent risk of inundation and entry of undesirable animals and fish .!* ppm . :olution of %'!( chlorine is active against bacteria."'*" ppm =Tripathy et al. buckets. Ase of chlorinated lime =bleaching powder> is the most suitable material for this purpose. crabs.All required appliances such as fry carriers. %7+&>. require thorough cleaning and disinfection before being put to use. etc. 2t eliminates the larger copepods which do appear in large numbers after organic fertilization.. $ost of these ponds have channels in the embankments connecting them with outside waters during the rainy season.. and also disinfects the pond water and soil. since it kills all the wild fish species. hapas. -hlorine is probably the most widely used disinfectant in fishery management and is easily available as a solution of sodium hypochlorite and powder of calcium hypochlorite =bleaching powder>. %76+>. $ost of the ponds lack even proper embankments. 4isinfection of appliances . :ome of the pathogenic organisms are found adhering to them and may cause disease if they are allowed to come in contact with the host fish species. 2t is applied at the rate of . utensils. :ome of the most effective and easily available disinfectants for such use are chlorine..2n addition to the natural fish food which is made available by fertilization. 4uring summer months netting should always be done early in the morning and it is better to have minimum possible handling during hauling. sodium chloride potassium permanganate.. frogs. but it fails to disinfect the pond. M asu! s in pond manag m nt7 @oisoning of pond . :ome of the common crustacean fish parasites also get killed. etc... sodium hydro ide. -are should be taken not to break the protective mucous coating of the skin. etc. 4isinfection can be done by washing or immersing in a concentrated solution of disinfectant. is also a practical method of disinfection. the greater is the stress and the risk of disease =/umar et al. 2n nursery and rearing ponds it is desirable to have second poisoning with malathion at the rate of ". $alathion application has significantly increased the survival level in nursery ponds =/umar et al. etc. or * days prior to stocking. $ahua oilcake is also a widely used piscicide. Fi ing fine meshed screen into these channels may eliminate the risk of entry of unwanted fish species into the pond. :un drying of nets. molluscs. hapas. These channels are the vulnerable sites through which some of the wild unwanted fish species or other animals get entry to the pond. an adequate amount of good quality supplementary feed is essential for maintaining healthy growth of fish. viruses and fungi but is e tremely to ic to fish and hence their residues must be thoroughly rinsed from the disinfected items before being brought into contact with fish. (! * ntion o' nt!y o' un%ant d 'ish7 $ost undrainable ponds lack proper embankments. R mo*al o' d ad 'ish '!om th pond7 4ead and apparently sick fish should be removed. D posure time should not be longer than one hour. 4ip treatment in *""'% """ ppm solution of potassium permanganate for a few seconds before releasing adult fishin ponds is also a very effective and practical prophylactic measure. Feeding antibiotics with feed has successfully prevented the occurrece of -D =-arp Drythrodermatics> in Duropean carp culture. molluscs. :everal commercial vaccines are now available and being used in many developed countries. of penicillin has been found to be very effective in preventing outbreak of columnaris disease in rohu in a field-oriented e periment =/umar et al. :uch records will provide valuable insight into the problems and may lead to their solution. . The oral route is used in prophylactic treatment to prevent certain infections. @rophylactic treatment of pond with locally available organophosphorous insecticide =malathion> at the rate of ". including fish. / pa!ation o' young and 3!ood 'ish7 <rood fish may serve as carriers of disease causing organisms without e hibiting any clinical symptoms. Eaccines for some of the bacterial diseases of carps which do occur in undrainable pond culture systems are also available. :hort bath for a few minutes in ! or )( common salt solution is also a safe and ine pensive prophylactic measure against a wide range of parasitic an microbial pathogens.. Immunop!ophyla4is 2mmunization is becoming one of the most important ways of preventing communicable diseases in animals. serve as intermediate hosts for many parasites that infect fish. These vaccines are againstAeromonas hydrophila and Fle ibacter columnaris. ?olding the fish in a hand net and dipping it into a concentrated solution of the drug for one minute or less is used as prophylactic treatment in case of mild diseases. 5ccasional application of potassium permanganate at the rate of ! or ) ppm is recommended for increasing dissolved o ygen concentration and hauling prophyla is.. Tadpoles and frogs may also act as carriers of certain parasites and bacteria which ultimately may infect carp species and hence such animals should not be allowed in the pond. H.. :ome fish eating birds. Eiral vaccine against :pring Eiremia of -arp =:E-> is also being used on a commercial scale very successfully. 2t is generally conceded that feeding medicated feed to fish is a prophylactic rather than a curative measure. A short bath is useful when facilities for a rapid flow of water are available. @rophylactic use of streptomycin and penicillin at the rate of !* mg of streptomycin sulphate and !" """ 2.species. To avoid such risk. A daily log of losses must be kept. A long bath is a very effective method for prophylactic treatment of pond fish for e ternal parasites.A. %7+&>. the best course is to separate the young ones from the adults. etc.!* ppm of active ingredient successfully prevents occurrence of trematode and copepod infections. They sometimes become survivors of previous epizootics due to built up immunity but retain some of the pathogens.). #ater flow is stopped and relatively high concentration of the drug is added.#. Agitate the pond water by splashing. especially during the early morning hours. beating with bamboo poles. 1F.. frequently occur causing serious problems again in terms of dissolved o ygen. The following steps are recommendedF • • Add freshwater in the pond by pumping it from nearby sources. The following remedial measures are recommendedF • • Apply chemical algicide 4iuron simazine =Tafazine> at the rate of )'* ppm.2 -pp a!anc o' algal 3looms Algal blooms of $icrocystis sp.# Common ca!p p!o3l m . is the most common behavioural symptom. ?owever. 2n small ponds cover part of the pond with duck weeds or other floating weed like @istia to reduce the amount of sunlight entering the pond.. :top feeding and fertilization till normality is restored. -ut all the trees1branches shading the pond. <ased on the available data the commonly occurring serious hazards are discussed and remedial measures suggested. To avoid entry of undesirable fish. mass killing and decay of algae may also cause 45 depletion. taking care to prevent entry of unwanted fish. Duqlena sp. Apply potassium permanganate at the rate of !') ppm. • 1F. • • • • 1F.ime at the rate of !"" kg1ha and rake up the bottom. . 2t creates situations where supersaturation of o ygen occurs during day time and serious 45 depletion takes place during the night. sometimes leading to a mass fish kill. The growth rate is seriously affected and very often it may result in a mass fish kill. 4epending on the situation and availability of resources all such steps should be taken promptly which may help raise the 45 level of the pond. use a screen around the mouth of the intake pipe. Kradually cover the whole pond. This will result in the death of algal cells. Kulping for air. etc. M-N-+&M&NT OF COMMON H-J-RD/ :uccessful management of any farming system should anticipate several incidental hazards and keep ready remedial measures to deal with the situation.1F. Add fresh water if possible from nearby sources.. part by part.1 D 'ici ncy o' dissol* d o4yg n The most common and serious hazard in the composite fish culture ponds is the depletion of dissolved o ygen level in the water. repumping with the help of a pump or using a mechanical churner1aerator. <y adopting this technique the common carp population is efficiently controlled and sufficient quantity of common carp seed is also produced =Fig. • • • /eep constant vigil on water level. ?arvest the fish before such a situation is encountered. <efore it drops below the %. the rate and ratio of stocking of different carp species in composite fish culture ponds are liable to get greatly altered during the grow-out period. Figure . 8epair and strengthen the dykes before the onset of rains. while during seasons of heavy rains the incidence of flooding is not uncommon.<ecause of early maturity and natural breeding. A shallow tube well could be of some help to fight against drought. The following morning these plants are replaced by fresh plants and eggs are transferred to hatching hapas.!. /eep alternative source of water ready for such occasions. This problem can be overcome by placing at one corner of the pond some floating weeds such as Dichhornia during the breeding season. .!* m mark. The common carp will deposit eggs on the roots of the floating plants.) (!o3l m o' no !ain and pl nty o' !ain 4uring drought the water level drops down to critical levels in some ponds.!>. . water should be added from nearby sources. Dichhornia with attached common carp eggs 1F. Dntry point and spillway should be properly guarded by strong fine meshed steel netting. :tretch and fi barbed wire in criss-cross manner in the pond. 2f the leaking water is clear and flow velocity is sluggish it may be seepage water and hence there may not be any immediate danger. To locate the hole. occasionally row a boat with hooks or barbed wire hanging from its keel to detect gill nets. bran. frogs and birds cause problems mostly in nursery and rearing ponds. birds. snakes. . immediate steps must be taken to locate the hole on both sides of the embankment. These are carried by water into the leak where it swells and stops the leak. sufficient material and . (oaching @oaching is perhaps the biggest problem in freshwater aquaculture. 2n large ponds. Frogs normally lay eggs in shallow pits along the sides of seasonal nursery and rearing ponds during the first monsoon shower.8 $ a6ag s in m3an6m nt :ometimes leakages do occur in embankments and if not checked immediately they could cause e tensive damage to the pond embankment. @onds in the vicinity of the fish farmer3s home are less likely to be affected by these predators than the ponds that are isolated and seldom visited. 2n case the water flow is fast and muddy. $uddy water shows soil erosion and washing away of soil particles. ?igh value and ready market for carps make them more prone to poaching. • • • 1F. especially along the sides. etc. 1F.. 2n case of ma9or breaches which may occur and cause severe damage to the embankment. into the upstream site. heavy turf sod should be thrown on the water surface which gets attracted towards the hole and the sod may come out of the pond through the hole. frogs. All such spots should be identified and the eggs should be destroyed.eakages can be checked by pushing sawdust. 1F. (!o3l m o' p! dation <y far the most important and damaging predators of fish in ponds are otters. etc. gill nets and small drag nets. Trained dogs used for night watch minimizes the risk considerably.. The following measures have been found to be most effective against such forms of poachingF • • @lace branches of trees and bamboo twigs in the grow-out pond along the sides. . <ird-scaring devices. :nakes. The widely used gears for poaching are cast nets. #hirling action of water may be noticed 9ust above the leak if it is big.• ?arvest the fish before the flood season if cost of protection becomes too high.. including fire crackers should also be used if the problem becomes severe. Fencing the farm with barbed wire and employing the services of watchmen are efficient means of preventing poaching. 5tters can be prevented by putting a fence around the pond.ursery and rearing ponds are usually not prone to poaching. bamboo nettings and sand bags to facilitate repairing the breached portions with earth and sand bags. 2f you prevent the disease outbreak you have virtually no loss.1 Mic!o3ial dis as s About one-third of the economically important fish in the world perish every year through disease and about &"( of these losses are due to microbial pathogens. by strictly adhering to the fish health monitoring programme.i!al dis as s .@.. 2deally. . 1F. etc. bacteria and fungal pathogens come under this category.2 Common dis as s All the Asiatic carp species cultured under composite fish culture undrainable ponds are prone to many communicable and non-communicable diseases. Eirus. 2n an undrainable pond system no addition of water or aeration is normally done and the accumulated wastes are not usually removed unless provision is made to desilt the pond after a couple of years. 4etails about the disease prevention measures and prophylactic treatments have already been discussed under -hapter on O Fish health monitoringP. 1F. metabolic waste products.1 + n !al consid !ations The fish farming system in general is unique in that the cultured animal is cold-blooded or poikilothermic and lives in [email protected] resources must be mobilised. Also. viz. mainly two viral diseases are of importance. The outside of the banks should be protected first to prevent further erosion. the drug may not provide remedies under all circumstances. eliminate and prevent the entry of pathogenic organisms. but if you want to cure the outbreak you will always have some losses before you treat and cure them. Also. @reventive measures have always big advantage over curative practices.As far as carp species are concerned. . This saying has great value in fish health management. left-out feed materials and organic load of the pond bottom regularly come into contact with certain vital organs and tissues.. the aquaculturists should strive to decrease the stress causing factors. where the respiratory o ygen level is limited and may become lethal at times. the drug may not help the host survive the infection until the environment is improved =/umar et al. %7+!>. A semicircular bundh may be constructed on the inside with brushwood. $oreover.@.@ Out3! a6 o' dis as s 1F. the most significant among them are described here under four groupsF 1F.2. There is a common saying that an ounce of prevention is worth a pound of cure. All such factors can cause deterioration of fish health and magnify the risk of outbreaks of diseases. prevention of disease through prophylactic measures and treatment and control of disease outbreaks using fish therapeutics. There are two strategies for the management of this hazard. dark colouration. :ome of these bacterial diseases. -olumnaris . 2n some countries virus-free brood stock are maintained and propagated. etc. serious liquid deposition in the abdominal cavity. if remained unchecked. 8E. Although a number of pathogenic bacteria have been isolated from diseased fishes cultured in undrainable ponds =/umar. rearing and stocking ponds. There is also strong evidence that :E. <lood sucking parasites@iscicola qeoimetra and Arqulus foliaceus have been found to be vectors. @eritonitis with serious haemorrhage is normally present in acute cases. from common carp =-yprinus carpio>. 2n most of the Duropean countries where :E. The main clinical signs are gathering of fish at water outflows. The disease was known as O 2nfectious dropsy of carps P till the isolation of the virus by Fi9an et al. bleeding in the scale bases.is strainspecific and hence the ma9or outbreak is concentrated in Durope. There are some other disease conditions of common carp suspected to be of viral origin which are yet to be investigated in detail. a condition caused by bacterial agent. inflamed vent.poses a big problem largescale vaccination of the stock is undertaken which has lowered the losses to a greater e tent. They have become increasingly apparent during the last few years and are of serious concern to fish farmers. airbladder. There is no method of eliminating the virus from the infected fish and under no circumstances should such fish be used for breeding purposes. Application of antibiotics helps only in prevention of secondary infections. inflammation of the alimentary canal. Columna!is dis as 7 The causative agent of columnaris disease is a Kram negative bacterium Fle ibacter columnaris that moves by a creeping or fle ing action. =%76%>. Frequently there is secondary invasion of the tissues by aeromonads and pseudomonads from the intestine resulting in the bacterial septicaemia. e ophthalmia. the following are worth mentioning. Rha3do*i!us dis as s o' g!ass ca!p7 A new serotype of rhabdovirus similar to spring viremia of carp virus =:E-E> and 8habdovirus carpio =8E-> has been isolated from grass carp =Ahne.C27 :pring viremia of carp is an acute systemic viral infection caused by 8habdovirus carpio =8E->. a condition caused by 8habdovirus carpio and -arp Drythrodermatitis =-D>.is pathogenic to all ages of common carp and perhaps to other cyprinids =Ahne. The actual role of these micro-organisms vary from that of primary pathogen to an opportunist secondary invader. lower respiratory rate. %7+%>. etc. The virus is shed through faeces and possibly urine. pale liver. %76*> which causes large-scale mortality e hibiting more or less similar symptoms like :E. swollen spleen. necrotic fins. Avoidance requires that sources of virus be detected and the agents identified. :inha and Farkas =$:>. have the potential of wiping out entire populations./p!ing *i! mia o' ca!p 0/. 2nternally they show haemorrhages in the viscera. -ontrol methods for viral diseases are restricted as there is no chemotherapeutic measures available at present. opacity of the inner wall of the swimbladder with haemorrhages.disease such as ventral haemorrhagic inflammation. All the measures are directed towards avoidance of the pathogen and propagation of pathogen-free brood stocks. etc. Fi9an =%76!> subsequently separated the dropsical syndrome into spring viremia of carp =:E->.. haemorrhages especially over the skin and gills. 9act !ial dis as s7 Among infectious diseases the role of bacteria has been strongly emphasized as they present many practical problems in nursery. loss of balance. %7&+>. 9act !ial ha mo!!hagic s ptica mia is used to designate septicaemic diseases caused by Aeromonas hydrophila and @seudomonas fluorescens in carp and other species. 2f the fish are able to feed. but once the infection has become systemic the disease is usually fatal. As long as the disease is confined to Ge ternal lesions. e ophthalmia and abdominal distensions =Figure . The stress of crowding =#edmeyer. Aeromonas hydrophila =organisms previously described as A. incorporation of o ytetracycline in the feed at the rate of + g1%"" kg of fish1day for %" days is also effective. especially increased o ygenation. liquefaciens> is a gram-negative bacillus. punctata and A. lesions spread and may cover most of the body. The causative agent is a species of Aeromonas and by inoculating a pure culture of the isolate the disease has been e perimentally produced in fingerlings of catla =-atla catla>." ppm> and potassium permanganate =!') ppm> in pond treatment.. %7&%>. #hitish ulcerations and haemorrhages may also be observed. <acteria apparently gain entrance to the dermal tissues as a result of in9ury. facilitate the transmission and outbreak of the disease.*'%. including copper sulphate =".)>. 8ecently. are the most valuable supportive therapy.. which may be accompanied by e ternal abscesses. especially high temperature and1or overcrowding.>. systemic infections or both. @ractical control of outbreaks of columnaris is possible with a number of drugs. Dnvironmental improvements. etc. 2nfectious dropsy condition among cultured ma9or carps in 2ndia is the most common e ample. handling =/umar et al. Earious other treatments are also employed including dip treatment for %'! minutes in %F! """ copper sulphate colution. and as the disease progresses. %7+&> or holding them at above normal temperatures as well as the stress of e ternal in9ury. 2t affects most of the cold-blooded aquatic vertebrates including Asiatic carp species and causes acute and fatal septicaemias. Aeromonad infection is usually associated with concomitant environmental stress. control can be successfully achieved. %7+&>. multiply in the connective tissue and reach the musculature where they form red ulcerations. 2t should be noted that fish may harbour cutaneous lesions. %76. 5utbreaks of columnaris appear to be related to unfavourable environmental conditions such as low o ygen levels and accumulations of metabolic byproducts =$eyer. Drosion of the gill lamellae may also be observed. several cases of dropsy condition in catla caused by mi ed infection . 4iagnosis of columnaris disease in fish is usually based on the presence of the bacterium in typical e ternal lesions on the body. ubiquitous in nature occurring in water column and top sediment of most freshwater ponds.disease is commonly occurring throughout the world and affects virtually all species of freshwater fishes. control of organic addition. 2n rohu =.abeo rohita> the necrotic lesions begin at the outer margin of the fins and spread towards the body =/umar et al. The type of lesion varies with the fish species.abeo rohita> and mrigal =-irrhinus mrigala> =Kopalkrishnan. ulcers. The disease begins as an e ternal infection with lesions appearing on the body surface and gills. rohu =.. :imilar septicaemiasis have also been reported in silver carp =?ypophthalmichthys molitri > caused by @seudomonas fluorescens and Aeromonas hydrophila =/umar and 4ey.of Aeromonas hydrophila and my osporidian species has been described =/umar. Ca!p !yth!od !matitis7 This disease =-D> is probably the most widespread disease of carp in Duropean ponds. oedema of all organs and finally anaemia. :aproleqnia sp.ovember and 4ecember. Although most treatments are generally ineffective. :kin inflammation is followed by e ophthalmia. caused by aeromonads in catla was restricted to the eye. 5 ytetracycline at the rate of 6. 2n some cases the disease." g1%"" kg of fish1day for +'%" days. Toor. $ishra and 4ey. ?owever. %7+)>. ) . @ond treatment with potassium permanganate =!') ppm> followed by addition of o ytetracycline with feeds at the rate of 6"'+" mg1kg fish1day for %" days are the most effective and practical measures. o ytetracycline or chloramphenicol or furazolidone in baths =+"'!"" g1m > or o ytetracycline or chloramphenicol as intraperitoneal in9ections at the rate of %"')" mg1kg have been found to be very effective =Fi9an. certain water additives during the transport or handling of fish are helpful. %76&>."'+. %7&%>. intraperitoneal in9ection or with food. The causative agent is the Aeromonas salmonicida comple . and the fungus. :ehgal and :ehder =%7+)> have also observed haemorrhagic septicaemia in common carp and rohu caused by heavy infection of Aeromonas sp. . The disease was found to be seasonal in nature with ma imum intensity during the month of 5ctober. chemotherapeutics are applied as bath. in acute cases the brain and optic nerves were found to be affected =Kopalkrishnan. Acriflavin was found very effective for such purposes when used at the rate of )'%" ppm. %7+*>. For the control and treatment of -D. Aeromonad septicaemia in rohu =.)A.abeo rohita> .Figure . $y obacterial comple have been found in the affected gills causing hyperplasia =Fig. and Achlya sp. <ranchiomyces sp.>. are usually implicated in fungal infections.. etc.. All the stages including the eggs are attacked. $alachite green =zinc free grade>. The disease is found to be widespread and infectious in nature. The ubiquitous fungus. Two subsequent treatments after an interval of one week completely cures the disease =/umar et al..:aprolegnia sp. salt. especially the brood stock. :hort baths for *'%" minutes in )( common salt solution has been found to be more effective than treatment with antibiotics. formalin. during the postspawning period.Figure . :pecies of the genera :aproleqnia sp.. -ommon carp is observed to be more susceptible than other Asiatic carp species. is another filamentous fungus which obstruct the blood vessels in the gill filaments causing discolouration and finally dropping off altogether leaving the cartilaginous support e posed. $alachite green at the rate of ". Fungal dis as s7 Fungal fish diseases also sometimes cause e tensive losses.)<. copper sulphate. can affect a wide range of fish species including most of the carp species. 2nitially it appears as white mats over the skin which gradually spread and invade the deeper tissues causing mortality.% ppm . . Aeromonad septicaemia in catla =-atla catla> 9act !ial gill dis as 7 8ecently gill hyperplasia syndrome has been detected most frequently in common carp fry and fingerlings causing retarded growth and poor survival.%7+&>. potassium permanganate. are the common therapeutics for effective use. <ranchiomyces sp.. but they are considered to be secondary invaders following physical or physiological in9ury brought about by rough handling or attack by primary pathogens. 2chthyophthirius multifilisF O2chP or white spot disease is probably one of the most detrimental diseases caused by this parasite which affects all the species of 2ndian ma9or carps and -hinese carps as well. 1F.2. 2ncidence of large-scale mortality due to this infection is common in nursery and rearing ponds. . encourages multiplication of parasite organisms and resulting in e tensive parasitic infection. The following are the most important protoizoans parasitizing carp species in undrainable pond culture system. %( solution as a swab and &* ppm concentration as short bath1dip for )" seconds are used.*>. O2chP is a ciliate protozoan parasite characterized by its relatively larger and horseshoe shaped nucleus in adults and large trophozoites. . The most common symptom is the presence of pinhead size white spots on the skin.@. fins and gills =Fig. (!oto=oan dis as s are among the most significant of all parasitic diseases in carps.2 (a!asitic dis as s @arasitic diseases are usually encountered more frequently than microbial diseases. The presence of high level of organic matters in undrainable ponds.for pond treatment.* to %." ppm depending on total alkalinity. 2t causes simple hyperplasia of the epidermal cells around the site of infection forming blisters. -opper sulphate may be used for pond treatment at the rate of ". A.<. Kill :ection of $a9or -arp showing .Figure ..amellar ?yperplasia due to <acterial Kill 4isease =? S D :tained> .. Kill :ection of $a9or -arp showing .ormal :tructure =? S D :tained> Figure . @ond treatment with ".. %76!>.euteu and $eyer. . Dpizootics are usually encountered in nursery and rearing ponds associated with poor water quality and high stocking density. if a pond has dense plankton population. 2ch 4isease 2chthyophthirius multifilis> Trichodina sp. sodium chloride. 2t is an oval or kidney-shaped organism which produces severe irritation with e cessive mucous secretion causing patches over the body.% ppm malachite green and !* ppm formalin gives a better result against Trichodina sp. methylene blue.. D cess mucous secretion is a common symptom of this disease. Treatments for this group of parasites are varied and many are successful.F Trichodina is another small saucer-shaped protozoan parasite that harbours gills and body surface of the host fish. ?owever. and 2chthyophthirius sp. -ostia sp. $i ed treatment of malachite green and formalin is most effective against O2chP disease. sudden death and decay due to formalin application may cause o ygen depletion. can also be used. @ond treatments with %*'!* ppm formalin have yielded e cellent results.F A small flagellate e ternal protozoan parasite of skin and gills causes considerable damage in fry and small fingerlings. :ome other chemicals such as copper sulphate. etc.*.Figure . For O2chP disease three applications of the therapeutic mi ture on alternate days are essential =. 2chthyobodo sp. /umar and $ishra. breathing of the fish is adversely affected =4ey. whereas 4actyloqyrus effects only the gills. sometimes resulting in heavy mortality. apparently causing little harm. %7+*>. %7+!>.. the pond should immediately be dried and disinfected. cestodes and leeches. Treatment with !* ppm formalin in ponds or !*" ppm formalin for % h bath usually controls the monogenetic trematode infections. Among monogenetic trematodes. %7+&>. and 4actyloqyrus sp. gills and internal organs such as the kidney and spleen =Fig. <ath in )( sodium chloride solution till the fish start showing distress is also an effective control measure. g are more prone to this infection. fins. Kyrodactylus sp. for e ample is becoming an important menace in nursery and rearing ponds in many Duropean countries. <rothiocephalus sp.My4ospo!idian and mic!ospo!idian sp ci sF $y osporidian and microsporidian parasitic infections are very frequent in ma9or carp species. 5ther compounds which may be used include potassium permanganate at the rate of * ppm or potassium dichromate at the rate of !" ppm. if possible. :everal genera of cestodes have been found to infect ma9or carp species. $any of these parasites do not apparently cause much harm to carp species in undrainable ponds. Kyrodactylusinfects skin and gills. loss of scales.&>. ?owever. Another important member of this . 8eports of large-scale mortalities of fry and fingerlings of carp species are common due to such infections. . The most common symptoms of the disease are weakness. -arp fry and early fingerlings up to )'. copper sulphate or malathion at usual doses kills the free living stages of the parasite1mollusc population. @ond treatment with bleaching powder. Wo!m dis as s are caused by trematodes. 2n undrainable ponds where drying is not at all possible. . The disease is caused by posthodiplostomum and appearance of black pigmented area on the skin around the cysts of metacercariae is the common symptom =Fig. There is no known effective treatment against my osporodiosis and microsporodiosis. abnormal pigmentation and presence of parasites in renal tubular epithelial cells. D cessive mucous secretions. 2nfected fish should immediately be removed and. the pond should be disinfected with chlorinated lime. 8enal infections lead to the damage of most of the renal tubules in the form of vacuolar degeneration of the tubular epithelial cells =$ishra et al. some have been known to be of serious concern. <lack spot disease is a frequently occurring disease in nursery and rearing ponds causing e tensive damages at times. emaciation. ?owever. $olluscs act as the intermediate hosts and hence eradicating molluscan population and clearance of weed are the two steps for controlling the disease. The parasite harbours the intracellular spaces of the epithelial cells of the renal tubules =4ey and /umar. $icrosporidian infections are most common in catla among 2ndian ma9or carps.6>. :pores released from the infected and dead fishes remain viable for quite a long period in the pond bottom before they infect new hosts. scale protrusion. when large numbers of oocysts are present on the gills. are most important as sometimes they cause e tensive damage. :everal species of $y osporidia have been found to infect all the carp species and form cysts on the body surface. decolouration of body and dropping of scales are the diagnostic features. . The embedded head bears branching processes that resemble an anchor and hence the name anchor worm.ernaea sp.&.F 2t has a slender. or anchor worm and Arqulus sp.+>. wormlike body with the head embedded in the flesh of the fish which causes unsightly lesions =Fig. . These are . $y ogoan cysts on gill . or fish louse.ernaea may be found at the bases of fins or scattered about the body surface. $ain in9uries are caused by loss of blood and openings in the skin which allow entry of secondary pathogens. C!ustac an dis as s7 Two crustacean parasites are most widespread and commonly found parasitizing ma9or carp species sometimes causing large-scale damage in nursery. Figure .ernaea sp.group of fish parasites is . Darly infections may cause the fish to swim about erraticallyG in the later stages it causes haemorrhagic and ulcerated areas at the point of penetration. 2t causes abdominal distension and in advanced cases it may cause rupture of the abdominal wall. rearing and stocking ponds.iqula intestinalis. . <lack :pot 4isease in Fry1Fingerlings of 2ndian $a9or -arp .6.Figure . -ommon -rustacean @arasites .+.Figure . restlessness. the fish. they have been found to be of partial success in field conditions. the number and size of the fish and their specific requirements. Fish with advanced infestations are characterized by erratic swimming.iver lipoid disease =.+>. 1F. on the hostG possibility of penetrating the site of infectionG effectiveness under the e isting water chemistryG local availabilityG cost considerationsG .!* ppm.1 + n !al consid !ations Four key factors are of utmost importance whenever a chemical application is contemplated =$eyer and #arren..ernaea sp. haemorrhagic areas and lesions over the body with attached parasites. one may then begin to consider which drug or chemical should be used.# Th !apy o' 'ish dis as s 1F. %76*>. if any.2. infection is widespread and frequently appears in undrainable ponds. alkalinity. 1F.#. .# &n*i!onm ntal and nut!itional dis as s 4iseases known to be occurring due to nutritional deficiencies and environmental disorders are of little importance. and Arqulus sp. They are large copepods and consequently they are conspicuous ob9ects on the fish that they inhabit. p?. :election of the therapeutic compound must be based on the following considerationsF • • • • • • effectiveness against the causative agentG adverse effects. including potassium permanganate and sodium chloride. . /nowledge concerning the fish includes the species affected and unaffected. are also required for the selection of the most suitable drug. 2nformation about the causative agent is based upon correct diagnosis and the vulnerable stages in its life cycle. The parasite is easily recognised by flat. dissolved o ygen. Although a number of therapeutics have been recommended for the control of . 4ata about the pond water temperature. $alathion is an easily available organophosphate having relatively low to icity to humans and has been found to be very effective in controlling copepod parasitic infections when applied at the rate of ".@. etc.4> in catla and gas bubble disease in early fry of rohu are worth mentioning.. -omplete information about each of these factors must be in hand before any therapy is planned. infections. :ometimes it causes serious problems resulting in high [email protected] sp. the causative agent and the chemical. #hen all of the foregoing data are in hand. They are the water. Two subsequent treatments at the interval of one week completely eradicate the parasite. leaf-like carapace with emerging appendages =Fig. @roper monitoring and management of pond ecosystem and provision of adequate quality of supplementary feed will avoid occurrence of such diseases which sometimes appear in ill-managed ponds.@. total water volume. +. 2t is reemphasized that the success of therapy depends very much on the correct diagnosis of the problem. $oreover. . 4epending on the available facilities. %". .). it should also be considered that disease outbreak is the indication of more basic environmental problems and hence such problems should also be identified and corrective measures taken.• convenience of application. 2ndefinite bath is suitable for pond treatment where the chemical is applied at a low concentration for an indefinite period and the chemical is allowed to gradually dissipate or deto ify naturally. three types of immersion treatments are suitable for undrainable pond culture situations. severity and nature of the disease and local conditions.7>. These are baths in lower concentration of chemicals ranging from short to prolonged periods and dips where the fish are dipped into a chemical solution of high concentration for a very short period ranging from a few seconds to * minutes.! M thods o' th !ap utic application Therapy can be applied in two waysF • • e ternal treatmentsG treatment via dietG &4t !nal t! atm nts7 There are two methods of application of e ternal treatments. 2mmersion in chemical solutionF The most common method of administering therapeutic agents to fish is immersion in water soluble compounds =Fig. ?owever. i." mm mesh.aw of diminishing returnsP starts operating. market demand. Feeding should be stopped a day before harvesting to minimise the conditioning time required for transporting fry over long distances. A . T! atm nt *ia di t7 This method is usually applied for treating the systemic bacterial diseases or gut parasites by incorporation of the drug into the feed.oss of appetite is one of the first signs of a disease and hence in such cases the use of drugs in proper doses through supplementary feeding becomes difficult. Treatment of Fish by 2mmersion in Tnerapetic :olution :wabsF :wabbing is application of drugs in high concentration when dealing with individual fish with localized e ternal infections.. ?owever. ?arvesting should be done by seining the pond using a drag net of about +. the biogenic capacity of the pond. . Kenerally. The most suitable time for harvesting is the early hours of the morning.eeching of drug is another problem.1 Ha!* sting in nu!s !y ponds 2n nursery ponds the fry usually grow to a size of !*')* mm in about a fortnight with more than 6"'+"( survival.e. especially the bottom feeders is usually difficult and hence several netting should be done to ensure near total harvesting. when they become ready for harvesting. 11. H-R.* mm> drag net. are the ma9or considerations for deciding on the time of harvesting. i. Further. cannot be increased after a certain stage according to the need of the increasing fish biomass.e.7. in some cases fingerlings are to be kept for a prolonged period for marketing during the period of scarcity of seed to fetch better price. This happens mainly because the growth rate of fish is not linear. feeding medicated feed is considered to be a prophylactic rather than a therapeutic measure. 11. 11. 2f some of the water soluble drugs are properly mi ed with vegetable oil prior to its final mi ing with the feed. . desired market size. ?arvesting should be done by seining the pond water using a close meshed =%.o harvesting should be done on a bright sunny day or in cloudy weather as there might be heavy mortality of tender fry due to high temperature related increased metabolism and the depletion in available dissolved o ygen.2 Ha!* sting in ! a!ing ponds ?arvesting of fingerlings should be done after three months of rearing when they attain the desired size of %""'%*" mm. For better convenience it is desirable to immobilize the big-sized fish prior to swab application. .Figure . such losses may be minimised. availability of seed and pond condition. :everal netting operations should be done to ensure near total harvesting of the stock. capacity of water for providing food and o ygen for the fish.&/TIN+ Krowth rate of the fish. complete harvesting of all the species. ?arvesting the fish stock should be started before the O. the rate of growth of the fish for the invested inputs such as feed and fertilizers start declining. @ossibility of partial harvesting very much depends on the availability of fingerlings of desired carp species. This factor should also be considered before deciding on the harvesting programme. This kind of differential growth complicates the final harvesting programme and hence in such areas partial harvesting of marketable size fish should be carried out. :uch partial harvesting programme should be synchronised with peak market demands depending on seasons. 2ndian ma9or carps on an average attain hardly % kg in size in a year.modified form of net which is described below is very effective in catching all the species of carps even in rearing ponds. Further. 2n such cases the fish already reached the marketable size should be harvested and the stock should be replenished. the rearing period should be synchronised accordingly.1 Compl t ha!* sting Asually the carp species attain marketable size within one year and hence the shorter rearing period of less than a year is not recommended unless there is an e ceptional threat of flood or outbreak of disease. or for financial reasons.ovember. <ottom feeders like common carp and mrigal partly subsist on the faecal matter of grass carp and hence an unplanned removal of grass carp may affect the growth of these species. festivals.2 (a!tial ha!* sting 2t has been e perienced that even under the best management. in larger water bodies and especially for partial . interrelationship of the species cultured should also be seriously considered. i. 11. 2n regions where seeds of desired cultivated species are available only during post-monsoon period. while -hinese carps reach over ! kg or so. Asually these cultivated fish species do not grow well in winter months. ?ence in agroclimatic zones having severe winter months the stocking and harvesting phases should be ad9usted so as to have complete harvesting before the onset of winter.# Ha!* sting in "!o%:out ponds 11. 5n the other hand. and also in cases where the pond is prone to serious flooding.#. ?owever. the stocking should normally be done during this period and the crop should be harvested by ne t 5ctober. Feeding should be stopped a day prior to harvesting.) -pplication o' p!op ! g a! ?arvesting of fish in undrainable ponds should be done by seining the entire pond using desired size of drag net. while harvesting. @ost-flood stocking and pre-flood harvesting should be done in flood prone ponds while in seasonal ponds harvesting should be done before the water level falls below the critical level. removal of only bottom feeders may create some ecological problems. 11. months with simultaneous stocking with fingerlings. 5ctober1. etc. the market price of fish is directly related to its size. 2n some e ceptional situations when the pond is of a seasonal nature retaining water hardly for &'6 months.e. 11. Asually fish over *"" g should be harvested every )'. ?owever.#. The following procedures should be adopted to keep the fish in good condition.1 T!anspo!t o' '! sh 'ish Fish perish more quickly than chicken. ?arvesting should be done during cool. This results in the formation of pockets of !" M )" cm.. A new gear has been designed by 8out. The free bottom part of the net is provided with a nylon twine =). cast nets and gill nets too can be effectively employed. The net is provided with a strong head rope with polythene floats =Fig. @roper care and prophylactic measures should be taken before releasing back the potential breeders. clear weather and time should be ad9usted according to the market hours. 12..harvesting. whereas the catch of bottom dwellers fall in the range of !"'. Fry. and the spoilage is mainly due to combined effect of autolytic and bacterial decomposition which is rapid in tropical climate. 11. The net is prepared by 9oining net pieces of %* M * m with + mm mesh for fingerlings and !* mm bar mesh for large sized fish. ." mm> with sinkers and passed through the bottom series of meshes. etc. pork. ?arvested fish should always be kept under proper shade after washing. fingerlings and table size fish are the main products of undrainable ponds which require different ways and means of disposal. All the anti-poaching devices kept in the pond should be removed before netting. TR-N/(ORT -ND M-RG&TIN+ 2mmediate disposal of farm products in perfect condition adds to the overall farm income and reputation. about 7"( of the surface and column fishes are caught.akshmanan and /anau9ia =%767> which can be operated in rearing and stocking ponds with increased efficiency and significant reduction of manpower. *">. $etal sinkers are tied to the first foot rope in each pocket to keep the mouths of the pockets open and also help the net sink in the bottom silt. 2t has been observed that by three subsequent operations of simple net of dragging type. Feeding should be stopped !') days before harvesting. beef. Table-size fish after harvesting need immediate transportation so that it may reach the destination in fresh condition whereas fry and fingerlings are to be transported in live condition. (! cautions • • • • #eed infestation if any should be removed before harvesting. • • 12. ."( of their entire population. The free end of the net is then turned over to the main net and attached at equal intervals to a second line of nylon twine which functions as a false foot rope. they should be kept under shade and washed properly with clean water to remove the bacteria adhered to the surface of the body and the gills.2.Figure *". but always in shaded areas. -onditioning time depends on the distance to be covered and the anticipated time of confinement during . Although a number of containers and enclosures can be used for conditioning. *%> and kept for about & h with continuous and vigorous splashing of water from all sides of the hapa. two systems are presently in useF the open system for short distance and the closed system for short and long distance transport. the fry and fingerlings are transferred to the conditioning hapa =Fig. -over with wet bags or clothes and transport it at once. fingerlings and brood fish to destinations. Artificial feeding therefore should be stopped %'! days before harvesting. Kenerally. 12. $odified .2 T!anspo!t o' li* 'ish For safe delivery of live fry. the most common is the hapa made out of cotton or nylon mosquito netting material fi ed in the pond or in a still water section of a stream or river. -over the fish with layers of a mi ture of ice and salt.!( sodium nitrate solution.1 Conditioning and p! pa!ation 'o! t!anspo!t This involves starving the fish prior to harvesting and keeping them in overcrowded condition for emptying their gut and to make them accustomed to the conditions of transport. colour of the gill is an indication of freshness. -leaned fish should be given a one minute dip in ". Kills and gut should be completely removed if there is no ob9ection from consumers. After netting. • • • 12.et with $easurement 4etail • • The moment the fish is harvested. ?andling during netting and transport should not be allowed. a rhythmic 9erky movement is created which keeps the water well aerated. Op n syst m o' t!anspo!t This is the traditional system of transport where fish seed materials are transported in open containers. .2. These containers were earlier in the form of earthen hundies which have now been replaced by aluminium vessels of about !*'. *!>. <igger galvanised steel containers of about *" to !"" % capacity sometimes mounted on a thermal insulated base of wood or other materials are also in use for transport of fry and fingerlings for short distances. 2n the case of fingerlings or advanced fry transport. The ever increasing demand for carp seed has created a great impact upon village level seed production activities in recent times. 4ead ones are periodically removed with the help of a piece of cloth and the water is changed partially but frequently during long distance transport. The optimum temperature for conditioning carps is around !&'!7H-.transport. -onditioning of brood fish in hapas is not required.2. 2n the case of brood fish the application of supplementary feed should be stopped ! days before the proposed date for transportation. Darthen hundies help to keep the water cool. 4uring this period they pass their remaining e creta and the gut becomes almost empty. 8isk of outbreak of diseases becomes high due to the stress created during transport and hence the use of antibiotics is recommended. :uch vessels are normally carried manually or by train. #ater is filled up to two-thirds of the total capacity of the vessel to transport about % """'* """ early fry =%!' %* mm> depending on the anticipated period of transport. 12. in spite of its many limitations." % capacity =Fig. but due to high risk of breakage they are now going out of use. the mouth of the container is always kept covered with cotton or nylon mosquito netting material. This method of open system of live seed transport for short distances is of significant relevance for localised marketing scattered throughout the region. #hen they are carried manually. Farmers are now taking up induced breeding of carps and the seed are now being reared in their backyard or ponds. Figure *%. -onditioning ?apa . o' s % """ ' %" """ *"" ' * """ !"" ' % """ !"" ' *"" 6* ' )"" *" ' !"" d 0Rang 2 * *"" ! !"" &"" ))" !!* +" No. o' s d 0-* !ag 2 .">. Tanks vary in size but usually )'.& cm which can be accommodated in %+ % capacity biscuit tins after being filled with water up to one-third of its capacity.2.umber of seed materials to be packed per bag vary according to their size and e pected duration of transport =Table . Aluminium -ontainers =?undies> for Transporting Fish :eed @lastic pools and canvas bags with varying degrees of capacity are also used for transport of fry1fingerlings and brood fish under open transport system. if needed in larger quantity. :uch a system offers safe transport of live fish upto a distance of about *"" km with mortality as low as *(. 2mprovements have been made and now plastic cushioned lining is provided to the tank for avoiding physical in9uries. . %7&!> / % ! ) . hours with ease.# Clos d syst m o' t!anspo!t For transporting live fish and fish seed over e ceedingly long distances and from one country to another. These are mounted over bicycle. Tanks are covered with wet cloth and some persons are employed for continuous but gentle splashing of water. * & d si= 0cm2 No.. tanks are accommodated on a truck. can be made from cylindrical rolls. closed system of transport is most suitable. tractor trailer. 12. 8elatively bigger truck mounted open tanks are also in use with or without facilities for mechanical aeration and1or water circulation. etc. @olythelene or vinyl chloride or other plastic bags of various capacities ranging from %*')* % are in use. Table . :uch tanks are used in organised fish seed marketing sector. #idely used size is . These bags can be purchased ready made from the market or. Fry." @acking density of fry1fingerlings of 2ndian ma9or carps for %! h 9ourney in %&'%+ % capacity plastic bags =$ammen. and used for short distance transport.6 cm M . :ome sort of aeration or water circulation is provided by a pump during transportation. fingerlings and brood fish are usually transported up to distances covered within )'. The water for such use should be clean and preferably from a tube well. motor van.Figure *!. 2n this system of transport live fish1seed materials are packed in closed containers with o ygen under pressure with airtight seals. 2t has been observed that *"" mrigal fry =!&' )* mm> can be safely kept alive for a period of !. The bag is then partially blown up with o ygen and tied with a leak proof knot. thereafter refilling of o ygen becomes essential =Fig. %7+%>. *)>. metal or wooden bo es to prevent any damage to the bags during transport. At )"" fry1& % of water the fry survived for a period of 7& h without any mortality =:elvara9. <est results are obtained when it is kept between !"'!+H-." After putting the required number of fish seed in the plastic bag containing water. A total weight of !*" kg of live fish can be transported in such a tank. $ohanty and Khosh. A bio-gas-plant type of live fish carrier has also been designed by @atro =%7&+> which consists of an outer lower circular chamber of about %. a cycle pump is used to pump atmospheric air into the plastic bags containing fry in & % of water. 2t can transport %"" kg of fish at a time safely up to * h.* % of water have been successfully transported to distant places. An o ygen cylinder is also kept on the carrier as a standby for emergency use.! m diameter opening at the top to which is fitted the upper inverted one of slightly smaller dimension. The outer lower chamber serves as a storage tank which is filled with water along with the fish to be transported while the inner chamber serves as an o ygen reservoir under pressure. These plastic bags are individually packed in cardboard. A simplified method suited to rural condition has been developed for fish seed transport in a closed system where instead of o ygen. <rood fish are also transported in some larger closed containers mounted on wheels and pulled by 9eep or a tractor. . autoclave type airtight lid and a built-in aeration system which works by the engine of the transporting vehicle using belt transmission. About 7" """ carp fingerlings with fish to water ratio of % kg to .. The top of the inner chamber is closed and. 2t must always be kept in mind that the live fish packets should not be e posed to temperature over )"H-. The modified splashless live fish carrier =$ammen.6 + !* ' %"" !* ' *" 6" . provided with a valve and air vent. h with %( mortality. This is a tanker having a capacity of % %*" % with lining of synthetic padding. <iscuit or oil cannisters of %+ % capacity are widely used for such purpose. %7&!> is useful for transporting brood fish as well as fingerlings. o ygen is pumped into the water until it is saturated. 2. 4rugs and chemicals are used to reduce the metabolic rate. thus cutting down the production rate of ammonia and carbon dio ide. . :uch situations reduce the stress .Figure *).ive Fish -arrier 12.) D!ugs and ch mical aids @roduction of to ic gases such as ammonia and e cess amount of carbon dio ide as metabolic waste products are the main causes of stress condition and mortality of fish in undrainable ponds. product marketing of any production system is the core activity upon which the future of the industry depends considerably. :ome of the easily available fish anaesthetics such as . 2n such situations marketing involves offering the products in proper form. Ase of antibiotics and some other fish therapeutics help in reducing such risks. . occasionally sprinkle cool water over the metalic containers to bring down the temperatureG before releasing.. 2mportant operational stepsF • • • • • stop feeding %'! days prior to transportG condition under shade up to & h before packingG use tube well or chlorine free tap water or clear pond or river waterG select only healthy and vigorous fry1fingerlingsG plastic bags should be checked before and after o ygen packing to check any possible leakG carriers of fish1seed containers should be covered to avoid strong sunlightG when resting during the 9ourney carriers should be parked under shadeG if atmospheric temperature is high. fish seed materials . barbital sodium at the rate of *" mg1kg of fish. %7+)>. -arbonic acid has been found to be useful in fish seed transport. tertiary amyl alcohol at the rate of ! mg1. 2n fact. time and place desired by the consumers. the bags or hundies should be floated in the water where the seed are to be released at least for %"'%* minutes to equalise the temperatureG slowly mi the pond water and gradually release the fishG if anaesthetic is used. Ander stress conditions fish become more prone to attack by pathogenic bacteria. A concentration of *"" ppm of carbonic acid in the transport medium itself was found to be optimum for rohu fry under o ygen packed transport =$ishra. but these products are used by the industry itself.are also important products of pond fish culture. $s !!! is also a common tranquilizer which can be used for anaesthetizing brood fish in a %F%" """ to %F)" """ solution for %* to !" minutes. 2n addition to fish.ovocaine at the rate of *" mg1 kg of fish.* % can be used for anaesthetizing the fish to be transported. /umar and $ishra. prior trials should be made as the doses vary with the water quality and the species of fish.effects. fry and fingerlings . 2n case of fish production system. • • • • • • 12.# Ma!6 ting $ost of the ma9or cities and fish sale depots are far away from the rural fish production centres.spawn. marketing assumes relatively greater importance because of the highly perishable nature of the product. There may be several functional links =about . grading. 5ut of many market channels."1kg compared to an average price level of A:V %. especially in Andhra @radesh where freshwater aquaculture is emerging as an industry. 12. 2n the absence of easy accessibility to the market." in other states indicating the demand and supply gap.#. freshwater carps are in ma imum demand where 6"'+"( of the population are fish eaters. Also. the fish traders and middlemen e ploit the poor fish farmers. The fish seed production1demand picture is 9ust the reverse. and distributing to retailers.%>. the shortest and best possible channel in the interest of both producer and consumer is the direct one. 2n some southern states. @roper marketing strategy is needed to stabilize such imbalances in the larger interest of the producers and consumers. agents and distributors serving as links between the producer and the consumer.2 Ma!6 ting o' ta3l si= 'ish $arketing functions or services include many aspects such as collecting small quantities from many producers. The term O middlemen P is often used to describe a wide variety cf collectors.#. transporting to distant city based wholesale markets. @rices are also related to state of freshness of the product. the local preference for carp species is relatively less and hence the surplus is marketed to #est <engal. 2n some of the eastern states of 2ndia. Fresh fish fetches a better price and are in greater demand than iced fish. 2n addition to the seasonal variations in the market price. The e isting price of freshwater carp in #est <engal is around A:V ).*'!. mainly due to increased harvesting prior to pre-stocking pond preparation for the ne t crop.> between producers and consumers through each market channel and at every link they charge about *'!"( for their services. especially in #est <engal and in countries like <angladesh.12. fish is sold to the middleman at the farm gate invariably at a much lower price than what it would have fetched in the retail market. and financially indebted to money lenders are compelled to sell their produce to the middlemen in fulfillment of the conditions of loan taken for fish culture operation. fish farmers who are generally poor. #est <engal is a surplus state which produces ma imum quantity of fish seed through controlled breeding and supplies to other states in 2ndia.1 Ma!6 t pot ntial There are areas that have a higher per caput production and also there is a regional variation in consumption pattern. The . Kenerally speaking. The volume of fish sale is normally at its peak during $arch1April. packing. fish prices increase due to increased demand during the time of religious and social celebrations. -alcutta markets in #est <engal receive about )" """ t of fish per annum from other states of 2ndia. Asually the consumers pay about 6"'+"( more than the producer3s price. <ut this channel is operative only during special occasions when the consumers need the fish in bulk for some social and festive celebration. ignorant of market dealings. -onsiderable portion of the fish is sold in fresh condition. @rice variations are also linked with the species and size of fish =Table . the state fisheries institutions were the ma9or channels for the collection1production and distribution of fish seed.+ Rohu !".& %.F 6g !.% which gives more or less the general picture of prices in fish markets of Dastern 2ndia.F 6g !. Appro imate cost of fish seed of carp species in 5rissa :tate is presented in Table .+ /il* ! ca!p . severe shortages of fish seed supply have been felt." !.+ . As a result.! -urrent price of fish seed =A: V>N Fish s :pawnNN d Catla !".7 %.& !.+ !.!.* !.& %.* %.A +!ass ca!p .! %.. 4ue to increased adoption of composite fish culture technique throughout 2ndia. Table .+ M!igal ca!p !+.current market price of carp species in 5rissa markets are given in Table .% -urrent market price of fish in 5rissa R tail ma!6 t p!ic 0-pp!o4imat 2 0U/ D2> /p ci s 9 lo% F.A Common ca!p !". -ollection of seed from scattered seed production centres and ensuring redistribution of the collection to fish farmers in remote villages is the responsibility of the organized sector.& F. There are two general patterns . 12. while a localised marketing system distributes fish seed to nearby villages through local agents. The price of fish seed varies according to size and species.* %. $any state and private hatcheries were established during this period and e tension services were put into action to promote induced breeding at farm level.F 6g N % A: V T %*. #ithin a few years this trade has grown to a considerable size.F : 2.! %.6 1. and to satisfy this growing demand the Kovernment took immediate steps to increase the production of fish seed.! !." %.) %.# Ma!6 ting o' 'ish s d Antil recently. 6g -atla 8ohu $rigal :ilver carp Krass carp -ommon carp %.* %.the more or less organized one through fish seed syndicates and cooperatives and the other which is highly localised in operation.."" 2ndian 8upees Table . : 1.! !.% %.7 !.* %.#.7 -3o* 2.* !. many small and big seed producers emerged and consequently fish seed marketing became operational.* %. " +."')".ormally the crop is ready within %* days. fingerlings of grass carp.& &"."+*."' 6". A more generalised case of fry rearing operation in a ". . 1#.!."' . its market price and the cost of material and labour inputs." .!."' ."'.* +. ha pond in the region of 5rissa has been taken here as an e ample =Table ." .FryNNN =!*')" mm> FingerlingsNNN =+"'%!" mm> %&."'. . %"" A: V1ha from each crop of about ) weeks. 1#. the present analysis is based on the %7+& market price."'&*.* .!.A T 2nformation not available. it is necessary that undrainable pond culture operations are sub9ected to economic analysis which would indicate the factors influencing farm profitability and the way in which these factors of production are to be regulated to ma imise net return. . the economics of fingerling rearing naturally depends upon the size to which it is grown.)'%!.arge =above %"" mm> and healthy fingerlings fetch almost double the price of smaller ones." 2ndian 8upeesG NN @rice1%"" """G NNN @rice1% """G .".1 Raising o' '!y The economics of fry rearing mainly depends on the size to which they are grown =!* mm to )* mm>.raising of fry from spawn. Again. 1#." N %A: V T %*.".)>. Although the prevailing cost of catla.* **.are considered below. Therefore. The net profit is appro imately .". the present economic consideration is based on the latter group of carp species.)'%!. silver carp and catla are in high demand and fetch ! or ) times higher price." +. Dconomic analysis of all the three types of undrainable pond culture . &CONOMIC/ OF CU$TUR& O(&R-TION/ -ost of production is more important than the rate of production and it is the cost benefit ratio which decides the viability of any production technology. ?owever. nursery size." *".2 Raising o' 'ing !lings Fingerlings =%""'%*" mm> production involves rearing of fry for about ) months in rearing ponds.". costs of inputs. There is great variation in the market price of the product itself which mainly depends on the size and species of the marketed fingerlings.ikewise. The fry of certain other carp species such as grass carp. :inha and 8anadhir =%7+"> worked out the detailed economics of fry rearing on the basis of %767 market price.ormally )'. species reared and the demands for seed." )". silver carp and catla are sold at about double the price of fingerlings of the same size of species like rohu. mrigal and common carp. raising of fingerlings from fry and raising of table size fish from fingerlings . such crops are raised from the same water area during the rearing season of the year.!.)'%!. grass carp and silver carp fry are more than double than that of rohu. . ."."" +".* . Again the rate of stocking is also considered at a lower level of ) million spawn1ha. but disposing of fry itself takes about a week. %&& A: V1%""" fry> 6! """ fry )"".. :tocking material ". etc.&& %". -. . IN(UT %.N&T (ROFIT 09:-2 .!* % of oil> 6. R&TURN %."+ ha in 5rissa :tate is presented here =Table ."" kg %! kg %. using mahua oil cake ). :elective poisoning of larger copepods using malathion . @ond rental %!.>.)) %". Table . output and net income from "."" ). fertilization.%! million =spawn> at the rate of ) million1ha +."" %%.!" %)*..". The economics of fingerling raising in an average rural.mrigal and common carp."" !.etting charges for nursery preparation and harvesting %". :oap and oil treatment =6!" g of soap and !.6" *"."" &. #eed clearance !. undrainable pond of ". !" man-days %%.. 2nterest on working capital at the rate of %+( =for si months> Total input cost 9.abour for watch and ward.. mrigal and common carp> No."" %&."" +. feeding. $aintenance and miscellaneous %).. :upplementary feed 7. . 5rganic manure .!* !" kg %"" kg .) @roduction cost. ha nursery ponds =rohu.*" !. .)) %.6" +. Dradication of predatory and weed fishes."" ml &. Fry =at an average survival level of &"(>G =at the rate of .6* It m Iuantity Cost 0U/ D2 C.)) !".ime *. @roduction cost. Table . etc."+ ha pond corresponds to an income of A: V ! 6. kg Iuantity Cost 0U/ D2 ). initially )'.ime 2norganic fertilizerF Area Triple super phosphate & 6 + Fry at the rate of ". output and net income from ". 2f the ponds are relatively small and suitable for rearing of spawn to fry stage..)! )".)) ). feeding."" 7 7"."+ ha rearing pond =rohu. 4uring the rearing season of the year it may be possible to raise two crops of fingerlings from the same water body. 2n relatively bigger ponds.etting charges for periodical netting and harvesting . * #eed clearance Dradication of predatory and weed fish using mahua oil cake 5rganic manure=raw cow dung> . 7" man-days %& kg &.&.)) It m !"" kg .)6 %)."" %&.!* million1ha :upplementary feed .The net profit from this ". % ! ) . kg !" """ !!* kg ).)* %.abour charges for watch and ward."" kg !."" +). mrigal and common carp> No.&& !"."" !*. fertilization. they are utilized for culturing fish for about si months to an average weight of about *"" g.)61crop1ha in about ) months.+7 %" @ond rental %% $aintenance and miscellaneous %! 2nterest on working capital at the rate of %+( =for si months> . crops of fry are raised and finally the ponds are usually utilized for fingerling production.. after rearing ! crops of fingerlings.)! !"."" ). Three case studies have been selected to represent high =about + """'%" """ kg1ha1yr>. Table .6% C. """'& """ kg1ha1yr> and low level =less than .* gives the details of material inputs used in actual quantities. This shows that the technology of fish culture in undrainable ponds offers fle ibility to suit fish farmers of varied socio-economic background. dollars to have better comparability among three different levels of productions using different levels of inputs.*6 %& """ =at the rate of )). while Table . Fish production rates ranging from over ! 6"" kg1ha1yr to over %" """ kg1ha1yr.)) A: V1%""" *)). Input High % ! ) $ahua oil cake 5rganic manure =cowdung> .ime % "6% kg 7 "*6 kg % 6+& kg %" "&+ kg 6*" kg Int !m diat $o% % !"" kg 6 *"" kg )"" kg .Total input cost 9. The ma9or difference in terms of input cost is mainly due to feed component. the costs are updated =%7+& price> and e pressed in A. and use very little or no supplementary feed =8anadhir. which is ma imum in high production level while in the low production level it has not been used at all. ?owever.:. <ased on data collected from these sources detailed economic evaluations have been made =:inha.>.!+ fingerlings !%7.* @er hectare inputs1outputs in case studies of three different levels of fish production (!oduction l * ls No. """ kg1ha1yr> of production packages. All these three cases have been taken from 0aunpur -entre of the All 2ndia -oordinated 8esearch @ro9ect on -omposite Fish -ulture. %76+G :inha and 8amachandram %7+*G 8anadhir.& gives a summary of costs1benefits of fish culture in undrainable ponds. Table . Feed costs constitute *"'&"( of the total cost of production of medium and high input technology of composite fish culture. N&T (ROFIT 09:-2 1#. have been achieved depending on intensity of input use. medium or intermediate =.# Raising o' ta3l :si= 'ish The technology of composite fish culture in undrainable ponds has been successfully demonstrated in different agroclimatic regions of the 2ndian sub-continent at different use of input levels. %7+. %7+&>. R&TURN % Fingerlings =at an average survival level of +"(> )%). $any small-scale fish farmers do not use much fertilizers. The cost analysis presented here is also based on actual case studies. !* !"+.6".7" 7).6 !!).!* . intermediate and low production levels Costs 0U. %+" t & "6! kg ! 6%! kg * """ nos."" %!"."" %"6. estimated> $aintenance and repairs =estimated> $ahua oil cake =for eradicating predatory and weed fishes> 5rganic manure =cowdung> ./.ime !"+.& kg Table . It m High l * l Int !m diat $o% l * l o' o' l * l o' p!oduction p!oduction p!oduction -."" &!.. kg ! 6. IN(UT/ % ! ) . FertilizerF Ammonium sulphate $uriate of potash Area ." kg . 67."" !*".& kg *.!* .* kg )7& kg *" kg )" kg * FeedF $ustard oil cake 8ice bran + "67 kg * +"" kg * """ nos.6"."" !*". 6* t * """ nos %""'%*" t & 6 :tocking material #eeds 5utputF Kross production of fishF & 7+" kg ..*" .6" man-days.!* . D2> No.6"."" !*"."" +). * & @ond rental =estimated> #ages =.*" )6.& @er hectare costs and benefits of table size fish production at high.%" 6*.6* !"+. *" %&&..&* .) %! !6%."" & )"%.6+ % &+".)) % . %%7.!+ )6.)+ %.+) *%.) .%+ . 8esearch results have shown e cellent production .*6 6 %7%. fishermen and landless agricultural labourers.*) ) !++. %&+..and full-time occupation to the farmers.)+.&* +)..*" ).. Fingerlings %"..%6 A: V T %*."" 2ndian rupees 1).&+."" ) 7"!.)! ).&& ) &.%.6* !6. FeedF $ustard oil cake 8ice bran % &+). R&TURN %.6* &.*"1kg C."" .%& +.)) ! +6). 2ndia.&* +).%! )&!. -IU-CU$TUR& &<T&N/ION Aquaculture contributes significantly to the rural economy of most of the Asian and other developing countries by providing part.&! 6).%* % !&*..&& %&&.6"."" %&7. and other developing countries of the :outh Asian region are endowed with ample water resources in the shape of freshwater ponds and tanks for fish culture.+) 9. N&T INCOM& 09:-2 N %" .*6 %)+.). -ost of fish at the rate of A:V %. #eeds :ub-totalF %% $iscellaneous costs at the rate of *( of recurrent costs %+!.7* !!.%" =2tems%'%"> 2nterest on working capital at the rate of %+( for & months Total cost ).) 7.*" %&&. but these are not under effective and optimum utilization in spite of highly developed available technologies."" ! .!.6 FertilizersF Area Ammonium sulphate :ingle super phosphat $uriate of potash *". This involves situation-specific strategies. A local aquaculture e tension programme is relatively more definite in terms of scope and target. They are as followsF • • • @rogramme planning @rogramme implementation @rogramme evaluation 1). 1). 2t also aims at binging ma imum possible unutilized and under-utilized water areas under modern fish culture operation so as to raise the standard of living of the fish farmers through improving productivity and profitability. creating additional gainful employment opportunities. receive and interact with the involvement of e tension workers as a link between the two and a catalyst as well =model>. Agriculture e tension thus involves not only the e tension of aquaculture technology. 2n other words. 1). when developed in one agroclimatic region. the desired ob9ective cannot be achieved.2.1 O3A cti* Aquaculture e tension is basically an educational process by means of which scientific and technological knowledge of aquaculture is carried to the farmers to upgrade their e isting operation and farm management skills. there should be three sequential steps for the dissemination of fish culture technology in undrainable ponds. fighting malnutrition and preventing rural e odus. .ike any other aquaculture e tension programme. enhance the skill and knowledge of the fish farmers to upgrade their aquaculture practice. aquaculture is also an agroclimatic-based technology which.potential as well as economic viability of such technologies. but until these technologies are successfully transferred to the beneficiaries. but also certain levels of adoptive research in a particular field environment before it is launched for large-scale e tension. The philosophy behind this process is to change the altitude. it is a non-formal adult education programme for educating and training the rural mass to acquire suitable fish farming skills and capabilities with a view to boosting fish production efficiency and the socio-economic condition.2 $aunching a"uacultu! t nsion p!og!amm Any aquaculture e tension programme is designed based upon broad national consideration to achieve national goals and targets viz-a-viz local considerations to achieve short-term ob9ectives such as application of composite fish culture in undrainable ponds to improve the aquaculture production level. Apart from achieving its own target its overall ob9ective is also to signifiantly contribute towards rural development by improving rural economy.ike agriculture. . The main components of programme . may need modifications and refinement for adoption to another region.1 (!og!amm planning #hile planning the dissemination of fish culture technology one should always bear in mind that the programme should be a self-regenerating production endeavour and once it is stimulated should continue on its own with a changed attitude and active participation of the recipient. 2t is a two-way education process in which both scientists and farmers contribute. . $any small water bodies are found fully shaded by large marginal trees and thereby lying unproductive. 2t also helps to identify the local institutions.planning are pre-adoption survey of the area. The main ob9ective is to get an overall picture of the village and the villagers. pits emerging due to construction of mud houses etc. ?uman resources are the vital inputs in rural aquaculture development. • Availability of human resources 2t is a well-known fact that the ma9ority of the people in developing countries live in villages and most of the rural population depend upon agriculture. and the technological gap.arge. progressive farmers. setting programme goals and finally designing strategies in a sequential manner. -anal1road and village side small and large ditches. Eillage :urvey Fish culture is basically a rural farming system and hence village survey is the most common method for identification of the difficulties faced by the farmers and to find out the scope and suitability of a specific technology needing to be transferred =8adheysham and /umar. The village selected for the survey should be such that it may represent the locality.ow-lying and swampy areas which are formed naturally due to human activities are also potential sites for undrainable ponds for fish culture. the pattern of fish farming. 8egular contact with important and progressive farmers of the village should be maintained. village level workers in order to design the most feasible e tension strategy and also to establish a permanent rapport to strengthen the e tension services. 2nterviews with these persons will provide an overall picture of available natural and human resources and possible areas for development. values. At micro level it provides information about the socioeconomic conditions of individual fish farmers. 8ural areas have vast potential of . . their attitude. are some of the unnoticed and untrapped potential aquaculture resources suitable for seed production and short-term fish rearing =kumar. 8esource 2nventory • Availability of water resources Earious types of water resources are available for fish culture but usually all of them are not fully utilized. %7+!>. They should be informed about the ob9ectives of the survey proposed to be undertaken. school teachers. situation analysis. medium and smaller types of water bodies are generally available in villages which may be suitable for fish culture. aquaculture. livestock farming and other allied activities for their livelihood. mohanly and bhanot>. together with their socio-economic conditions and also to locate and assess the available freshwater resources. :ome unconventional types of water areas with potentiality for intensive aquaculture are also available.. Finally detailed relevant information may be collected from individual pond owners1fish farmers and fishermen through personal interviews1questionnaires. village leaders. .ike land distribution pattern. while small and marginal farmers have minimum water holdings at their disposal with adequate manpower potential to be utilized. possible sources for mobilizing credit facilities may be identified. etc. $arketing problem 2t is a general practice that the fish is sold to middlemen at the pond site who invariably pay lower prices. . ma9or water areas are usually found in the possession of medium and big farmers who bother least about fish culture and concentrate themselves mostly on agriculture. 2n some cases farmers fail to follow-up the prescribed package of practices strictly and land themselves in a state of financial turmoil and lose confidence in the viability of newly developed fish farming technologies.. At times.ack of technical knowhow :everal seasonal and perennial ponds without any proper embankments are found lying fallow in a derelict condition due to ignorance and lack of technical knowhow. Financial Farmers usually do not have surplus funds big enough to be diverted towards reclamation and renovation of e isting watersheds as well as construction of new ponds. 2mproper water area distribution pattern . species. 5ther material such as fish to icants are usually localised in its availability. @aucity of quality fish seed in the locality force the farmers to stock their ponds without any consideration to proper stocking size. • 2dentification of possible constraints A village survey also offers an e cellent opportunity to identify various constraints in the background of which an appropriate strategy can be suitably designed. 4ue to the perishable nature of the commodity and fear of e ploitation by the fish wholesellers. All such problems are also vital for deciding area specific e tension strategies. fish seed and supplementary feed is itself a considerably big amount to be e clusively borne by farmers themselves without any credit support. which can be effectively utilized in operating aquaculture =/umar et al. density. they procure riverine fish seed which is usually mi ed with the seeds of predatory and weed fishes. ratio. %7++>. farmers prefer to sell the crop at their pond1farm sites even at relatively lower rates. 2nitial e penditure for fish culture over fish to icant. As such. 2n some areas most of the water bodies are vested to village institutions.ack of stocking materials and other material inputs Fish farmers usually face the biggest problem of unavailability of quality fish seed for stocking their pond. local administrative bodies. 2nformation related to marketing practices will add to the scope of the e tension .unutilized or underutilized human resources for both men and women. etc. etc. education. 4ata collected during the pre-adoption survey provide the necessary information for such selection. Target groups may be selected on a number of criteria including farming practice.ocal administration such as @anchayats and <lock . 2t also provides reference level for evaluating the programme achievements =. )>. $ohanty and $uduli> . 2n some areas fish culture is supposed to be of a low-caste profession. initiative.2. cultural background. :ocial and administrative problems @onds remaining unutilized and lying in derelict conditions are common sights in rural areas in spite of a certain level of fish culture know how available with the farmers. production level. nature. income. Although the strategies and planning of the aquaculture e tension programme are situation specific.A-A lecture series .evel 4evelopment 4epartments are also not always suitable geared enough to ensure rural aquaculture development. programme goals may be set up and accordingly suitable e tension strategy may be planned. #ithout such an early insight and planning. Although the fish farmers are the usual target of any fish culture e tension programme. Koals indicate the direction towards which the programme is oriented. @oaching and deliberate poisoning of the ponds to destroy the crop are also serious social problems. liable to change their attitude. 5nce the plan is laid.2 (!og!amm impl m ntation O@lan the work and work the planP is an appropriate term for any e tension programme. . programme goals may be set up.programme so that farmers may be educated in marketing management to avoid such e ploitation. . :election of suitable communication channels is also very important. the programme may not have firm and realistic footing. 1). all the fish farmers may not be suitable to be involved for immediate participation. thus many efficient upper-caste prople remain reluctant to come forward for this venture. After these selections.o. :etting programme goals and planning 2n the light of resource inventory and possible limitations suitable target groups may be identified. schedules are followed arid activities accomplished as per the plan =/umar. 2n most cases such conditions e ist due to family rivalry and non-cooperation among the members of the owners especially when the water areas are under multi-ownership.ack of transport and efficient communication system 2n remote villages of 2ndia and many developing countries where fish culture technology needs to be e tended. proper transport and communication facilities are lacking. D amples of goals in such e tension programme may be on the following linesF • • improving the socio-economic uplift of fish farmers and raising the standard of livingG bringing %""( of the available undrainable ponds for composite fish culture. all possible efforts should be diverted to ensure that responsibilities are carried out. reputation in the society. some general steps may be cited as followsG . etc. fish feeds. techniques of fish seed transport. other culturable air-breathing fishes. weeds. 5ne or two demonstration centres may be set up and the technology of composite fish culture and seed production in undrainable ponds may be demonstrated to ma imum possible farmers to let them realize the case of operation. :elf-e planatory1pictorial instruction booklets dealing with basic steps of composite fish culture. • • • • • • • • . harmful predatory species.. etc. individual and mass contacts. publications. should be shown and the ob9ective and goal of the programme may be e hibited through models. techniques of pituitary gland collection. @eriodical netting for growth check1health inspection should be strictly followed and supervised. 2f the availability of quality fish seed is found to be a limiting factor. nursery and rearing pond managements. subsidy should be given as a token of initial attraction. etc. @roper attention may also be paid for e tending fish breeding and seed rearing programmes.. fish to icants. A set of suitable farmers should be selected initially and be motivated and guided enough so that they strictly follow the different package of practices as per the schedule. charts. Ad hoc training courses should be organized at the demonstration sites on different aspects of fish culture and fish seed production for participating and other interested farmers. posters. hatchery operation for carps. fish seed may be distributed free of cost or at concessional rate to the farmers at the initial stage. may be prepared. induced breeding of ma9or carps. @roper steps may also be taken to make available the critical material inputs at the pond1farm sites and if the programme permits.• • Through heavy flow of information using mass media.. 4aily talks on radio1tv may be organized to describe and discuss the technologies being e tended. :ufficient time should also be provided to discuss the farmer3s problems under field conditions. etc. Facilities for proper monitoring of water quality and fish health may be e tended through the participation of nearby laboratories. awareness and interest should be created among fish farmers. D hibition programme1Fish Farmer3s 4ay should be organized time to time at different places in which live specimens of all the si carp species. control breeding of common carp. @roper advice can be rendered immediately and1or the problems should be forwarded to research institutions. production potential and profitability. e plained and distributed among farmers. A short term and less e tensive localized e tension programme may be evaluated by the e tension workers themselves through the analysis of progress reports. 5b9ective of the programme in clear terms. village youths. 2t is convenient to fractionate the whole programme into smaller components for effective and easy evaluation. (!og!amm *aluation @rogramme evaluation is the process to determine the e tent of success of the e ecuted e tension programme in the light of present ob9ectives. prominent persons of the locality. @rogramme evaluation can be conducted once a year or at a specific period of the programme and finally at the concluding phase of the programme. Fractionation may be done as followsF • • • • • 8esources =financial. . etc. @hases of the programme =evaluation should also be done phase-wise>. 2ndividual contacts through home visits is a very effective e tension method. personnel an material> made available. 4ata collection from records and tabulation. research institutions. The e tension worker must be very clear in this ob9ective during the visit and must do sufficient preparation with regard to sub9ect matter information he is going to deliver to the fish farmer and family members. :ample selection -ollection of data1information from target and non-target groups Tabulation of data • • • . :election of ways. etc. broad-based and elaborate e tension programmes can be evaluated by specialists in association with the e tension workers to determine the effectiveness and impact of the e tension programme. field records. 2t is an important management function in order to ensure effective implementation of the programme. The process of evaluation also depends upon the nature of the programme. and sent to visit important aquaculture centres. questionnaires.2. Dvening is the most suitable time for organizing an assembly of farmers. ?owever. etc.• At times a team of a few farmers may be selected on the basis of their leadership quality and performance.#. Teaching aids may be used to make the communication effective.ecessary details about practices to be followed the ne t day may be e plained to them during such assemblies. means and methods for the collection of data1information from participating. non-participating fish farmers. 2t also helps in the identification of the deficiencies and weakness of the programme so that proper corrective measures may be taken to make it more useful in its future course. • • 1). farms. et al. fish breeding. :imilarly. $a imum potential for development of undrainable pond fish culture lies in developing countries where the prevailing literacy level is lowest. Ander such conditions the concept of community fish farming may also be considered as an effective and ideal method for organizing at least a section of the rural poor1fish farmers1fishermen in cooperative and productive communication =Tripathy. are diverted into activities totally unrelated to mass welfare. accept and adopt the new technology. and are reluctant to bring about quick changes in their attitude. hear and do. certain values have to be associated with the information.# Impo!tant consid !ations • • D tension services can be made most effective by making the people understand. The personality profile of e tension workers is of prime importance for the e tension of any rural-based aquaculture technology. social by temperament and preserve human values and missionary zeal of serving the rural poor."'*"( of what they see and hear and 7"( of what they see. • • • . easily approachable and adaptable enough so that he can live among fish farmers. are some of such measurable values for programme evaluation. At the same time he must not have any inferiority comple while meeting with specialists and higher bureaucrats. ?e must mould himself enough so that he may become technical by profession. etc. increased number of ponds1water areas in the area. however. $any e tension departments and voluntary organizations are also of the opinion that the gains of socio-economic and technological development progrmames do net reach the rural poor and that the roots of this failure lies in the lack of organization of the poor themselves. $ost of the resources allocated for various welfare activities of the rural poor. The target groups of aquaculture e tension programmes are usually socioeconomically backward rural masses having a low level of literacy and technical knowhow. 2ncreased fish production level. ?e should be simple. fish seed rearing. %7+!>. there are numerous instances where free educational facilities are granted for children of rural poor. as it is very much clear from statistical data that people remember %"( of what they hear.• 4ata analysis and interpretation of results To measure the degree of success. Field workers e perience very often instances of diversion of financial grants meant for production programmes for the small and marginal farmers into consumption subsidies. knowledge of modern management techniques. but they hardly avail the opportunity as they are treated as helping hands for supplementing family income.. The fact is that the poor are not only poor but are disorganized and hence they have very little influence in the process of decision-making and implementation of the programme. profit through increased fish yields. 1). . .>... 2nduced spawning of the -hinese carp.• :upport services and credit facilities are the two important factors which play ma9or roles in the aquaculture development programme. Fisheries 8esearch 2nstitute.. American @ublic ?ealth Association. such as site selection. %.>. -urr. %*th ed.. 4. • 1. A4-@18D@1+)1%+F76 p.Fish 4is.. @reliminary observations on -hinese carps in [email protected] Acad. %76*. 2ndian 0.$. 5lah.?.. /.=<>. . %"=!>F%+%'!". R&F&R&NC&/ A4-@ =Aquaculture 4evelopment and -oordination @rogramme>.. %7&). 8ome. :ukumaran. #ater quality and soil conditions of fish ponds in some :tates of 2ndia in relation to fish production. @arameswaran.%>Fpag.. Arch. p. -tenopharyngodon idellus =-:E> and the silver carp. %%)./. @roc.ack of appropriate support services and proper credit facilities are the ma9or drawbacks. ?ypophthalmichthys molitri =-SE> in ponds at -uttack. Dffective institutional support to provide the necessary technical services needed by the e tension programme. Alikunhi /. Eiraemia of carp virus in carp =-yprinus carpio . %7&&.?. /. and /. :tandard methods for the e amination of water and waste water. -yprinus carpio =. :ukumaran and :.. -tenopharyngodon idellus =-SE> and the silver carp. #. /. etc.. &"=)>F%6%'++ Alikunhi.+F%+%'* Ahne. Ahne. An interim report on the A4-@ Feed 4evelopment @rogramme. pp. FA5 Fish. %7&6. :ynop. A 8habdovirus isolated from grass carp =-tenopharyngodon idella =Eal.:ci.Eirol. %7&.?. pond environment monitoring.. #. @roc./. /. FA51A. <aner9ee. 2n @roceedings of the :ymposium on fish pathogens and environment in Duropean polyculture.:ci.. :. Aptake and multiplication of :pring. 2ndia. 2nduced spawning of the -hinese carp. .=%+!>F%%*'. %76+. :zarvas. :ynopsis of biological data on common carp. are vital for programme implementation. Fish feeds and feeding in developing countries. ?ypophthalmichthys molitri =-SE> in ponds at -uttack... #.%7')* Alikunhi.2@F-. fish health check. . 2ndia. %7+".innaeus. 0. =)%. %7&)a. )!F%")' !& Alikunhi..-. #ashington. pond designing. 2mportant viral diseases in Duropean fish cultures.var. ?ungary. A@?A-A##A-#@-F.?. %7+). %6*+> =Asia and the Far Dast>. edited by 0.Fish. %=)>F!&*'+ Ahne. %7+%. @. $ishra. packing and shipments of materials for laboratory diagnosis of fish diseases. 8.)'** -hen. Tissue level reactions in the 2ndian ma9or carp.. ./.I.at.. =!>F)" p.. edited by . Ase of mahua oil cake in fishery management. 8..2nland Fish. @hilippines./..a disease comple ./. 2n :ouvenir. and K. ?istopathology of $icrosporidia infection in 2ndian ma9or carp.)' 6% 4ubay.E. and /. )"F)7'*% Fi9an.?ist. %76&.2nst. -atla -atla =?am.@athol. Annual report. 2chthyologia. et al.8es.-.. @rotein requirement of grass carp fry =-tenopharynqodon 2della -al. %7*6. Aquaculture. K.-ent.>F)7'. <alasore. -2F82 =-entral 2nland Fisheries 8esearch 2nstitute>. . 4as. %"=!>F %!7'). Fish. France. /umar and <. %7+!.2nland Fish..2nland Fish.:oc. -arp culture. and 4./.Jool. *+F+%'7% Fi9an.8es...<ombay . $urugesan and :. %7&%. Aquaculture. pp. infection./. :oc .<hatia.8ep. 2-A8 Kolden 0ubilee.abeo rohita =?am. #orkshop on the development of inland fisheries in 5rissa through institutional finance.:ci. The effect of living space on the growth rate of fish.. 4ey. p.D. 2ndian Farming... Air-breathing fish culture.> @oster presentation at the :ymposium on aquaculture of carp and related species.8es. %7&+. !&')% $ay %7+& =mimeo> 4ey.D t.I. /amal and 8.. 5bservations on the spawning in 2ndian ma9or carps by hormone in9ection.E. &F). 4ehadrai. E. %766. $anila. 8. :ampling methods.@. -2F82.?. %76". %7&&. =)>F%. %7+*. 0. !&=%!>F)+%'+! -haudhuri. %%%=%'!>F%%'!" -2F82 =-entral 2nland Fisheries 8esearch 2nstitute>. and 8../umar.<arrackpore.ond. =%7&+>F7) p. FF4A. <arrackpore.. . 4. @aper presented at the First Asian Fisheries Forum.-ent. A new high in fish production in 2ndia with record yields by composite fish culture in freshwater ponds. %!F&)'6) 4ehadrai. %7+&.Tuli. ?. Annu. Aquacult./. %76&.A..<arrackpore. @. %7+*.D t.> due to $y obolus sp. !'* :eptember %7+* 4ey.. 5bservations in the breeding of ma9or carps in $adhya @radesh.. 4abrowski." -haudhuri. et al. !"=. 2vry. 2n :ouvenir. 2nfectious dropsy in carp . $awdesley-Thomas.. @rowse. Alikunhi. $. -urr. :emi-intensive and intensive culture of air-breathing fishes. ?. F. 4iseases of cyprinids in Durope. %76!. <arrackpore. %767. ?..>.$an.$an. %7+*.@. 2nst. . @athak. :ymp. 2n 4iseases of fish. Aquacult... 5rissa.2nst. /.-ent. . =)*>:uppl. 4ropsy of mi ed aetiology in -atla catla =?am. 5bservations on infectious dropsy of 2ndian ma9or carps and its e perimental induction. and E.. 4ey and /.-..%+!!>. 4ey and <. @ullin. <.K.@. FA5 Fish. %7+*.. 8./. 5bservations on raising the survival level of common carp fry =-yprinus carpio. and 8.> in nursery ponds by using malathion and certain prophylactic measures.F6)'+.:ynop.. 4.8. $ishra. E.E. =+>F%7 p Kopalkrishnan.<.A.. . <acteria from diseased fishes in 2ndia. France. <iswas.8ev. %7+*.K. %7+%. %76%. @aper presented at the First Asian Fisheries Forum. Aquacult. @hilippines. :inha and 0. 2n @roceedings of the :ymposium on ichthyopathology and its role in aquaculture. $an. 0hingran. !&')% $ay %7+& =mimeo> /umar. /umar. $anila. !"F)*6'+ 0hingran. 4.K. 2solation of the viral causative agent from the acute form of infectious dropsy of carp. ?ealth protection of fry and fingerlings in mass rearing operations. . E.Arhiv.. =%%>F%7% p. =%%%>F%"" p... %7&%.8es. E. :ynopsis of biological data on rohu. 2n @roceedings of the Fourth All-2ndia :eminar on 2chthyology. ?ypophthalmichthys molitri =Ealencienes>. @reliminary observations on gill hyperplasia of common carp in 2ndia. /umar../. et al. 4ehra 4un /umar. Iugoslavia /umar. 4ey.@ap./. %7+&. =$:> . . Eet. %76*. $ishra and <. FAR Fish. 4ey. !'* :eptember %7+* /umar. 4. -atla catla =?amilton %+!!>. Farkas. FA5 Fish :ynop./.. 0hingran./. %7+&. $ishra and 8. :ynopsis of biological data on the mrigal -irrhinus mrigala =?amilton. :ynopsis of biological data on catla.. %7+).8es../. <ihar Aniversity /umar. @oster presentation at the :ymposium on the aquaculture of carp and related species. 4ubronik. Fi9an.Fi9an. 5bservations on efficacy of carbonic acid as anaesthetic for 2ndian ma9or carps. 4. <acterial septicemia in silver carp. 2n @roceedings of the All-2ndia :eminar on fish biology. -arp production using domestic sewage. 8. %767. %7&&.2nd... E. %767. $uzafarpur. and ?.A. Dvry. /han. D2FATech... 4. =%!">F6+ p.. A hatchery manual for the common.. %7+*. 4. .<iol.%F%!*')+ Khosh.D t. =)!>8ev.abeo rohita =?amilton.:ci.:ci./. et al. 0. 2-.2nst. /han. <.=.>.>.<arrackpore.:.A8$ :tud.lF6+ p. and 8.:ynop. E. -hinese and 2ndian ma9or carps.@. ?. A.2nland Fish. %+!!>. 0hingran. .Fish./.. %7&!. <. 8ole of prophyla is in aquaculture. /umar and 8./.abeo rohita =?amilton>. 0. A new method of induced breeding by hypophysation of some ma9or carps in dry bundhs of <ankura./umar. and 0.orth America. %76%.:ci.#.8. 8eclamation of swamps for fishery development in 5rissa. %7...E. %F+6'7% .Fish--ult. $ishra. %7*&. <engal. @reliminary observations of intensive fish farming in freshwater ponds by the composite culture of 2ndian and e otic species.. and :. et al. =.*.>Eol.-ongr. A review of the parasites and diseases of fishes in warmwater ponds in . $azumdar and <.:oc. 5rissa. %7+!.%'*" $oitra..>. and F.@. 5bservations on renal my osporidiasis in 2ndian ma9or carps. F. 4asgupta. 2n :ouvenir. 4. 5bservations on the use of carbonic acid anaesthesia in fish fry transport.. 2n Training course on live fish transport. :.0ena..'&! [email protected]. :.. #arren. ?yderabad Fisheries D tension Anit $eyer././. :arkar. @roceedings of the :ymposium of finfish and shellfish. $.Aniv. %76*. Kovernment of 2ndia. Aquaculture.7 p. :arkar. <."*'+ $ishra. =%)>F6)'+.. %76). %7+)./. @roc././.4is.#ise. %76)=)>F*. %7&+. #est <engal. ?. $oitra.*F!7"')%+ $eyer. :arkar.. 4.. !F%'!% . 4isease prevention and control in closed systems. )!F.Aniv. #est <engal.2ndian :ci. <alasore. collection of egg and rearing of fry.8ep. 5bservations on the breeding habits of certain 2ndian carps in $idnapore 4istrict. F.2nland Fish :oc.. :. 2ndia./. and :. 2ndia $itra.. ?yderabad. %7+!. 5n the potency of pituitary gland e tract in relation to spawning in an 2ndian freshwater ma9or carp -irrhinus mriqala =?am.. et al.. :tress mediated columnaris disease in rohu.akshmanan. T. $angalore.Jool. Advis.A. -alcutta. !+F. %76+./. 2nduced breeding of carps by hypophysation in dry bundhs of <ankura district. 2n @rogress of fisheries development in 2ndia. . %76!.. :. ). $i tures of malachite green and formalin for controlling 2chthyophthirius and protozoan parasites of fish. -uttack. FA5 Fish.8ep.>F!6*'+! $ookher9ee. %7+&. FF4A /umar. Jool. @roc. #orkshop on the development of inland fisheries in 5rissa through institutional finance..@rogram. F. @rog. 7F+6'7 .ive fish transport using modified splashless carrier with compressed air aeration..2ndia. %76*. )=.=%>F!%'& $ammen. 4.eteu .:ea Krant -oll. $ishra.Anz.-alcutta. K. 0. 2n. et al. pp.. and :. with suggestion for breeding. $eyer..@ep.@. 0. 416*1")%.:oc.E. %7+). <angkok. :.. 5lah.ed.. <alasore =5rissa>. 2@F-1-&+1Tech. %7+&. &F%%*'7 8adheyshyam. Fisheries e tension for rural aquaculture. and /.. %7&7. %.. Kovernment of 5rissa. $. =mimeo> 8out. -ollege. . 6=l>Fl'* . 0. 4.2nland Fish. $. %7+. :atapathy and E.2chthyol.8. 5bservations on possible methods of averting hazards of loss of viable eggs in breeding hapas in rural ponds having common carp .A. 2n @roceedings of the 2nternational -onference on water hyacinth.' + 8anadhir. &F. @rinciples and methods of monitoring of perennial undrainable pond ecosystems in tropical monsoon lands.-.utrient requirements of warmwater fishes and shellfishes. %+ p. 5rissa. [email protected].. #orkshop on the 4evelopment of 2nland Fisheries in 5rissa through 2nstitutional Finance. %7&+.. :ingh. %7+&.. 5lah.A. -hemical control of water hyacinth .A. 4epartment of Fisheries.E. :oci'economics of aquaculture development in 2ndia. FA5. & p..2ntl. <.8. 2ndia. FF4A. and E. 2ndia 8anadhir. #eed control is a must in fish culture.@. %7+!. %7&+. Field document.$.8.'!+ 5ctober %7&+. 2n :ouvenir. . :inha. 0.@.. :inha. =7>F 6. /umar and E..2ndia.8.ational 8esearch -ouncil. K. F2.-. 4ehra 4un.ational Academy @ress. %7+).F%")'%" @atnaik.. %. %7+*.A-A. :.<. 2ndian Farming.2nland Fish. %7+. Fourth Advisory -ommittee $eeting of . . Dnvironmental diel cycle during mass fish kills and planktonic collapse in an undrainable rural fish pond. :arkar and <. @aper presented at the Thirteenth session of the 2@F-./anau9ia. 8ev.! . 2ndia. 8amachandran. $. @aper presented at the Fourth All-2ndia :eminar on 2chthyology. $odinagar . :udden fish kill associated with bacterial bloom in an undrainable fish pond.akshmanan and 4. A programme of investigations on the hydrobiology of fish ponds.. 8ome. $. Australia. %767.its economic significance and fertilizer value in fish culture. . double barrel type. An efficient gear for sampling and harvesting of bottom dwelling fish in ponds. 4as. %7+). <risbane. #ashington 4.) p. 4. A note on a new fish carrier. ?yderabad @atro. E.ovember %7+) =mimeo> 8adheyshyam.0. Aquacult.=mimeo> @rowse.! =mimeo> 8adheyshyam and 4. /umar. . 77'%"* 8adheyshyam.. 0. 2n :ouvenir. !7th 5ctober . %7+). :ome basic concepts on fish culture. :inha.Acad.?ung.A-A =FA51A./. @aper presented at the #orkshop on socio'economics of aquaculture development.. Dconomic analysis of composite fish culture. <hubaneswar.:[email protected]@ @ro9ect>.. =in press>. <. %! p.2nland Fish. %6F*% p./.:oc. 5bservations on the recycling of swine dung in composite fish culture. -2F82.'. et al. 2ndian 0. :aha. -. <.. 2ndia :in. 5bservations on the protein and carbohydrate requirements of carps.. 7F7+'%". for FA5.E. @reliminary observations on the transport of fish fry under air pressure. %766.. 5bservations on fish-cum-duck rearing. and 4.. %767a.2ndia. 5n the location and constructional aspects of freshwater fish ponds. %+'!6 :elvara9. <. %7*6.2ndia. @. =)>F66'+% :ingh. %)=!>F6*'7 :en. &F%!!')" :aha. Fishing . $anagement techniques of carp nurseries and rearing ponds.*'** :harma. @.. /.#. et al . Dnhancing production of 2ndian ma9or carp fry and fingerlings by use of growth promoting substances.. %76&.8.@. The dietary protein requirements for growth of young carp =-yprinus carpio>. Aquaculture././.. Farnham.. %)F!. 8ourkela.8. %).F!+. Khosh. %7+%. <arrackpore.<undesfor-schungsanst. 4ill.8.8.... =mimeo> :en. :tudies on the factors influencing spawning of 2ndian ma9or carps in BbundhC fisheries.2nland Fish.Fish.. -. @rotein requirements of an 2ndian ma9or carp.Fisch. :ahoo.. 2ndia..% :en. ! F %+7'7* :en. %7&7. 2n @roceedings of the :ymposium on inland aquaculture.. 2n @roceedings of the :ymposium on inland aquaculture. -onstruction of fish ponds. and E..-. :chr. -.:oil :ci.A. @. %767. :inha and /. = %.4.'7.td. :ingh. et al. %7+. .:oc. 0. -irrhinus mrigala =?am. <.. 2n :ouvenir..8. @illay and #m. %76+. pp. 2ndia. 5 ygen consumption and the amount of o ygen required for transport of rohu and mrigal fingerlings. 2ndia :harma. pp.> =Anpubl.:aha. 2n Advances in aquaculture. ?ongkong Fish. %76&.2nland Fish. <arrackpore. <arrackpore. -hatter9ee.<ull.:oc. @. edited by T.> .1 %* > Eol..8. :ummer 2nstitute on fish seed production and mobilization for culture fisheries of inland waters. 0. E. %767.. 0. Kopalakrishnan. %76. 8elative efficiency of different nitrogenous fertilizers in fish pond soil.?amb.8..ews <ooks . K.2ndian :oc. A. $ohanty and :. 2ncreased production of ma9or 2ndian carp fry by addition of growth promoting substances. 0.. %76). /umar.. :eminar on freshwater fisheries and rural development. :urrey. A. 2ndia. . %767.ondon. ?. 0.8. Freshwater fish culture. 2-A8 :inha %7+%.. %7+). Atkal Aniversity Tripathy.:oc. and $.. Takeuchi.@. 0. %76*.>F))%'.ew 4elhi. :mall-scale irrigation. FF4A.% Tripathy. [email protected]. 2ntermediate Technology @ublications .:oc. 2n @roceedings of the :ymposium on the utilization of animal resources of 5rissa. . 6F%)%'.2ndia. T.@. ?.8. $anage.0ap. -uttack.% :inha.:. -haudhuri. %7+*. 8eview of composite fish culture techniques. Availability of carbohydrates and lipids on dietary energy source for carp.. <hubaneswar. %76. %7+!.Fish.F. :ehgal and 8. <reeding of silver carp. E.=6>F!)"'% :inha. <. E. 2n @roceedings of All2ndia -o-ordinated 8esearch @ro9ect on composite fish culture. The effects of environmental stress on outbreaks of infectious diseases in fishes. *F!+*'7" :inha.4.@.*F766'+! Toor./.<iol .. E. %7=)>F *!&')+ :inha.@. . %76%. 2n @roceedings of the Fourth #orkshop on All2ndia -oordinated 8esearch @ro9ect on composite fish culture and fish seed production.> in a bundh type tank in #est <engal.Fish..:. 5n the growth of grass carp. 2ndia. @reliminary observations on the use of bleaching powder as fish to icant for preparation of nursery ponds. :inha. 2-A8. Aquaculture. #atanabe and -. E. ... .8.8. -urr. @.:. /umar. . ?ypophthalmichthys molitri =-SE> and grass carp. 8amachandran. %76*. A case study of acute fish diseases in tanks loaded with high levels of organic manures. 2-A8 :inha %76+. :ouvenir.. E... :. 8esour. )*F!66'+! Tripathi.. +" p. 8aising of fingerlings from spawn in nursery ponds.:inha..> in composite fish culture at /alyani. /umar and /.:oc. et al. 5gino.td. :tudies on nutritive value of dietary lipids in fish. @otential and constraints of small-scale freshwater fish culture enterprises in 2ndia. @roc../.. &=!>F%76'!"+ :tern.E. %767.5ptim. %&. Aquaculture. :ehder.. #orkshop on the 4evelopment of 2nland Fisheries in 5rissa through 2nstitutional Finance. :harma and . E. %76*. %7+". #est <engal.8. 8anadhir.?. -oncept of community fish farming. 0. <hubaneswar. -tenopharyngodon idella =Eal.:ci. #est <engal =2ndia>. %=. T././. . %76). et al. @ro9ect -o-ordinator3s report. -tenopharyngodon idella =Eal.8.2nland Fish..2nland. %7+". <alasore =5rissa>. and E. -omposite fish culture at /alyani.<ull. *F!"%'6 :nieszko... 4.@. 2ntegrated synergic approach to aquaculture.:ci.. :.@. and $. phenol red for &. iv. ). After ascertaining the appro imate p? value use suitable indicators to determine the e act p?. :hake gently and match the colour against standard colour disc for that indicator.> .a!-5) . :tress as a predisposing factor in fish diseases. Alkalinity 8eagents and equipments requiredF i.& should be used as indicators. 4ilute *" ml of this solution to make !*" ml to give ". A.! ml of universal indicator. Klasswares @rocedureF ii.&. The reading of scale at water surface gives the transparency value.*( solution in *"( alcohol :tandard ".-..a!-5) in % l distilled water to make ". iii. After adding the required indictor stirr the sample and match the colour against appropriate standard colour disc and read the values. v.4issolve *.#edemeyer.> stock solutions.".> . -((&NDI< I $ethods of #ater Ruality Analysis %."!=. <romothymol blue for p? range of &."!=.". .4ilute )".a!-5) using methyl orange indicator. Transparency Fi a bright new pin at the O"P point of a meter scale and dip slowly into the pond water till the pin 9ust disappears from sight. =F4." ml of conc. $ethyl orange indicator . ".."'6. 2nitially do the preparatory test with universal indicator to get the appro imate value of the p?."*( aquous solution."'7."!=.> .> solution.>?!:5.. 4epartment of the 2nterior. p? p? values can be measured directly by a p? meter by dipping the electrode into the pond water or by colorimetric estimation as described below. -heck it against ".#.+'+.> with distilled water to make % l to get appro imately %=. !.) g anhydrous and dessicated . %76. and thymol blue for +. @henolphthalein indicator . K. Fish and #ildlife :ervice.?!:".l=. ."!=. and 0.:. Take !" ml of this solution and further dilute it to make % l to get ". #ashington 4.> .+."!=.a!-5). =:. #ood.a!-5) stock solution.A. gravity %.-)+> F + p. @lace %" ml of the water sample in the glass tube provided with the colour comparater and add ". Add more distilled water to make % lG after bora is dissolved. $anganous sulphate .> ".."" g of $n:5.. @henolphthalein alkalinity =@> Take *" ml of the sample in white porcelain basin and add ! drops of phenolphthalein indicator.?!:5. ! ml of -onc. the end point is indicated by a colour change from yellow to faint orange. vi.Add . ".+" g of managanous sulphate =$n:5 .+! g of crystalline sodium thiosulphate =.4issolve !." % by adding more distilled water.> :odium thiosulphate .%"?!5>."!*=."!*=. but if it turns pink.+. v.=:p. -ool it and make it to %. $ethyl orange alkalinity =$>F @roceed as above using methyl orange as indicator.> .Take %. @rocedureF ."!* =."!*=. g of bora =.a2> in +"" ml of distilled water.56.a!:!5). through a burette to a colourless end point and calculate the value as per the following equation. -oncentrated ?!:5. a.*?!5>in 6"" ml of distilled water and add . iii.?!" or . .!!& g of potassium dichromate =/!-r!56> and dissolve in % l distilled water. titrate with ". 4issolved 5 ygen =45> =#inkler3s method>F i. vii. mi well and add more water to make the solution upto % l mark."! =. Add ) g of boric acid as preservative.>? !:5.!?!"> in !*" ml of distilled water. KlasswaresF Take %". :tarch solution ..a!:!5) solution using starch as indicator." ml of ". gravity %. 2f the sample remains colourless =@> alkalinity is zero.> @otassium dichromate solution . b. and titrate with ".Take % g of starch powder in * ml of cool distilled water.> /!-r!56 in a conical flask and add % ml of alkaline iodide. mi well and add %"" cc of boiled distilled water.a..a !<. ii. iv. Alkaline iodideF 4issolve 6"" g of pure potassium hydro ide =/5?> and %*" g of potassium iodide =/2> or %)* g of sodium iodide =. 4issolved free carbon dio ideF 8eagents and equipments requiredF i. Take *" ml of this solution and titrate with "." g of potassium iodide =/2> in limited volume of ammonia free distilled water and finally add this mi ture slowly to a cold solution of %%!..a!:!5) using starch as indicator to the colourless end point.. -alculationF 4issolve o ygen =ppm> T ml of ". -alculationF Free carbon dio ide =ppm> T ml of . ..a!-5) in % """ ml of distilled water.8.a!-5) required M !" .a!-5)> .itrate nitrogen> 8eagents requiredF i.* g of A... .a !-5) drop by drop from a %" ml graduated pipette with simultaneous gentle stirring with a glass rod till the colour turns pink.1%"> to . ii." ml of conc. @rocedureF Take *" ml of the sample in a conical flask and add ! drops of phenolphthalein reagent..) g . 4ilute to % l and allow to stand for few days and finally the supernatant liquid is decanted off into dark coloured bottle and kept for use.#ater samples for 45 should be collected in %"" ml 45 sample bottles without agitating. .> . if not. A whitish to deep brownish precipitate will be formed which will settle at the bottom.X. to dissolve the precipitate. 2mmediately after collection. 4evarda3s alloy ii. 2f the water turns pink there is no free carbon dio ide. bubbling or mi ing with air from the top column or bottom layer of the pond water as required."!* =. ?!:5. add ." ml with distilled water to get . @henolphthalein indicator.X. :odium carbonate =.*. .X.a!-5)."!* =. carefully remove the stopper and add % ml each of reagent =i> and =ii> by % ml pipette." g potassium hydro ide =/5?> dissolved in *"" ml of ammonia free distilled water.> . grade mercuric iodide and )*. 4ilute %"" cc of this solution =.a!:!5) used W .1.itrogen =Ammonia and . . <rown to red brown colour indicates medium to high 45 concentration. 8eplace the stopper and thoroughly mi the contents.4issolve *.essler3s solutionF dissolve *. . Add !. #hitish colour indicates poor 45 level while more deeper the colour of the precipitate higher the 45 level. ii. -ollect !* ml of the distillate.-. iv. 4ilute !6* ml of concentrated sulphuric acid to 6*" ml with distilled water separately.? . v.""% =:tandard of each disc division>.*( sulphomolybdic acid . 4issolved 2norganic @hosphorus 8eagents requiredF i. @rocedureF Take *" ml of filtered water sample in a .-.essleniser>. $i the solution and match the developed colour against standard colour discs for ammonia and nitrate after %"'%* minutes with a . $agnesium o ide =$g5> Ammonia free distilled water /9eldahl flask and other laboratory glasswares @rocedureF Take %"" ml of filtered water sample in /9eldahl flask and fit the flask with distillation unit. -alculationF Amount of Ammonia1.* g of stannous chloride =:n-l !.essler tube and add ! ml of sulphomolybdic acid and * drops of stannous chloride solution. $i thoroughly and compare the developed blue colour after )'.4issolve !.essleniser using standard colour discs for phosphate. minutes in a .essler tubes and add ".itrate . Add about % g $g5 and start distillation.. 4ilute to *" ml with freshly boiled distilled water and finally make the volume up to %"" ml by adding %. with constant stirring.* ml . !. distilled off. After cooling slowly mi ammonium molybdate solution to the diluted ?!:5. vi.5)-. !. @lace both the distillates in two separate .? .umber of matching division of the standard disc M %" M ". . This contains . This fraction of distillation contains . -ollect !* ml of the distillate in a separate receiver flask. @reserve the reagent in dark bottle by overlaying a thin layer of pure liquid paraffin. -ontinue distillation till all the .4issolve !* g pure ammonium molybdate in % !"" ml distilled water by warming at &"H-.iii.itrogen =ppm> T .!=. $ake the volume up to % l by adding more distilled water and store in dark bottles. Add % g of 4evarda3s alloy to the remaining sample of the flask and start distillation again.> ?-%.!?!5> in about * ml of concentrated ?-l with little warming..*( :tanous chloride .essleniser =<4? .esseler3s reagent in each. . :tandard Ammonium 5 alate solution . $i all the samples well to get uniform composite sample.% M !".. in such cases !" ml or more /$n5. :oil Te ture %. After removing from water bath add %" ml of ammoniumo alate solution. 5ne ml of this solution T ".This solution should be standardised against ammonium o alate solution in acid medium so that % ml of /$n5 . .% mg 5!> . #ith the help of a %" ml graduated pipette add drop by drop standard /$n5 .% mg of 5 !>.42W 22 $ethods of :oil Ruality Analysis $inimum five samples should be collected from a larger pond from soft layer.+++ g ammonium o alate in distilled water and make up to % l. iii.-alculationF @hosphate =@!5*> in ppm T 4isc reading for *" ml M ! M . solution =% ml T ". :amples should be air dried in shade and ground to fine powder by wooden hammer and strained through ! mm sieve. The pink colour of permanganate will disappear. ?ydrogent pero ide =&."(> ii."% iii. :tandard /$n5.% Kravimetric method 8equired reagentsF i. solution is to be added.% mg 5!.4issolve ".G> in distilled water and make up to % l. @rocedureF @lace *" ml of the filtered sample water in a !*" ml conical flask and acidify by adding * ml of dilute ?!:5. 4ilute sulphuric acid =%F)> . Add %" ml of standard /$n5.Add %"" ml of concentrated sulphuric acid slowly into )"" ml of distilled water. solution and keep on water bath for half an hour. -alculationF 5 ygen consumed =ppm> T .solution till the colour 9ust reappears.o of ml potassium permanganate required M ". A@@D. 4issolved 5rganic $atter 8eagents requiredF i. =% ml of this solution T ".T % ml of ammonium o alate. the number of samples depend upon the variability of the soil quality. ?owever. g potassium permanganate =/$n5.4issolve ". %. At times the pink colour disappears while heating on water bath itself. Transfer the soil to % l beaker.* g sodium o alate in % l of distilled water. Add !"" ml of distilled water and shake for !" minutes. similarly percentage of clay is substracted from that of clay L silt to get the percentage of silt. $ake correction to the scale reading by .> ?ydrochloric acid =.! ?ydrometer method 8eagent requiredF i. Allow the content to stand for an hour with occasional stirring.a>! ".a5? solution :ilver nitrate solution =*(> -oncentrated Ammonium hydro ide solution @rocedure F Take !" g soil in a .ii..> sodium o alate. stop stirring and note the time. @rocedureF @lace %"" g of air-dried finely powdered soil in a *"" ml conical flask and add %* ml of ".> . 4ry it in a beaker till constant weight is attained which gives the weight of silt and clay. 8epeat the operation after & hours to get the weight of clay alone.Y solution .>. =. The percentage of sand is obtained by deducting percentage of clay L silt from %"".*=. . 4ip the hydrometer in the suspension after * minutes which will give direct reading of the percentage of clay L silt. ?ydrometer reading after * hours of sedimentation and the temperature of the suspension gives the percentage of clay directly.a5? solution and shake for !" minutes in a mechanical shaker. minutes. :odium o alate =-55. Filter the soil and wash free of acid with hot water. Add more ?!5! when the reaction is over till no more frothing takes place. iv. :imilarly percentage of silt is determined by substracting the hydrometer reading for clay from the silt L clay. %. :tir the suspension thoroughly. tested by Ag. add + ml =.> $-l and !"" ml distilled water.4issolve )). add )* ml ? !5! while keeping the beaker on water bath.H-.ormally the hydrometer reading is ad9usted for the temperature of %7. shake vigorously for % minute and allow to stand for ."" ml beaker. -alculationF ?ydrometer gives the reading in g1% which can be converted easily into percentage of suspended matter.*=. @ercentage of sand is determined by deducting the percentage of clay L silt from %"". :uck !" ml of the content with a !" ml pipette from %" cm level. Transfer the content to % l capacity measuring cylinder and make it up to % l mark by adding enough water. iii. The contents now should be transferred to a % """ ml measuring cylinder. -ool and add *" ml =.5) solution. v. >!:5.6?!5> or )7!. 4issolve either !6+. Add water to make up to !"" ml and then add %" ml of reagent number =iv>. -arry out a separate standardisation blank also using all the reagents e cept the soil sample.* g and !. ?!:5. and make the volume to % l.adding ".. 5rganic -arbon 8eagents requiredF i.H. @rocedureF @lace % g of soil sample =". ii.>/!-r!56 so that % ml of Fe:5..8.. . Add %" ml of reagent =i> and mi thoroughly. Allow the mi ture to stand for )" min. =. 4ip the electrodes1electrode of p? meter into it and take the reading directly.?. Add .> Ferrous solution. add %* ml of conc.levels respectively> in a *"" ml flask. or =.H-.&?!5> in distilled water. grade> 2ndicator solutions . grade ferrous sulphate =Fe:5. ii. g A.%) g of ferrous ammonium sulphate =Fe:5. add %" g of air-dried powdered soil sample and add !* ml of distilled water. At the end point colour of the solution sharply changes to a brilliant green. ii.>Fe:5. sulphuric acid =sp. p? !.7.4issolve ". @hosphoric acid =+*(> -onc..8. iv. 4iphenyl amine indicator . solution T % ml =.>/!-r!56 solution.+.gr..) units for each degree below %7. @lace a layer of neutral barium sulphate % cm thick in a *" ml dry test tube.8.eutral <arium :ulphate =A.?. . Add !" ml of reagent =v> and mi gently by rotation.) units for every degree of temperature above %7. solution using % ml diphenylamine as indicator. =. Take %" ml of clear aliquot and follow the same procedure as under :ection ! of Appendi 2. grade potassium dichromate =/!-r!56> in distilled water-to make it % l. !." g of A.>.> Fe=.> @otassium dichromate solution.see :ection ! of Appendi 2.% -olorimetric method 8eagents requiredF i.or substracting ". :tandardise against =. =. iii.? !:5. iii." g for soils with e pected high and low organic .* g of diphenylamine in %" ml conc. v. %. Titrate with =.! @otentiometric method Take %" g of air-dried finely powdered soil sample in a beaker and mi well with !* ml of distilled water and keep for about half an hour with occasional stirring. and !" ml distilled water. shake well and keep it for settling.".>! :5. %=.>." g of sodium thiosulphate and again keep for %1! hour.ow add *.4issolve .%=.a5? .> . %.a!:!5).itrogen 8eagents requiredF i. -oncentrated sulphuric acid =A.> :ulphuric acid =?!:5. in a conical flask with a few drops of methyl red indicator. -lear blue colour of the solution indicates completion of digestion. ? !:5.%=. %.*?!5> %!=.%=.a5?> pellets in distilled water and make up to % l.>?!:5.>? !:5. i .%=. g of . viii.>.8.> standard solution. Add )" ml of conc.. 4issolve *.+.) vi. .a!-5) in % l of water to get ".> :alicylic acid =A. v. -opper sulphate @otassium sulphate @rocedureF Take %" g of air-dried soil in a /9eldahl3s flask. iv.a5? pellets in distilled water. Titrate the e cess of ".a!-5) solution.) g of . ii. with ".4issolve .a!-5)> solution.> ?!:5.8. Available .gr.%=." g of potassium sulphate and digest the mi ture. ". ". =stock solution preparation under :ection ) of Appendi 2> to % l and standardise against ".4ilute %"" ml of =. -alculationF Total nitrogen =(> vii. grade> :odium thiosulphate =. and keep in cold for %1! hour.+" g of sodium hydro ide =. -ollect about %*" ml of the distillate..a5? till the solution turns colourless. make up to % l and standardise against "." g of salicylic acid.%=.> :odium hydro ide . -ool and transfer with water to an ammonia distillation flask. vi.>?!:5.itrogen . grade sp.> . iii.a5? using phenolphthalein as indicator and distill off the ammonia collecting it in !* ml of ". %.-alculationF 5rganic carbon =(> T =Titration value =ml> for blank-titration value=ml> with soil> M ". Add %.%=. $ake it alkaline with e cess of %!=.%=. Total .> ." g of powdered copper sulphate and %". ".> :odium carbonate =. and %"" ml of !.a5? pellet in % l of distilled water.4ilute *" ml of ".)!( /$n5. Add !* ml of ?!:5. Add %"" ml of ". iv. !. iii. gives the following values under different concentrations. .> sodium hydro ide =.4issolve !* g of . . or /!:5.> ?!:5."! =.> sulphuric acid .4ilute %"" ml of ". =:ection ) of Appendi 2> with distilled water to make up to *"" ml mark and ad9ust the p? to ). v..a5? to a colourless and point.>! :5.!%7* g of dried monobasic potassium dihydrogen orthophosphate in ."!=. ii.% g of methyl red powder in !* ml ethyl alcohol and make up to *" ml with distilled water.a5? solutions. This will give a stock solution of *" ppm of @ =@hosphorus>. of this Appendi > $ethyl red indicator .>. !.?.8eagents requiredF i. iv.o."! .see :ection ) of Appendi 2 ". with a few drops of methyl red indicator and titrate with ".*( sodium hydro ide . of ml of ". @rocedureF Take %" g of air-dried and powdered soil sample in a /9eldahl3s flask. -ollect 6* ml of the distillate in the receiving flask containing !* ml of "."! =.*( :ulphomolybdic acid =see :ection 6 of Appendi 2> !.a5? required> M !. in distilled water and make the volume up to % l."" ml of water." with =.> ?!:". This ! ppm of @ solution. iii.+ !.*( :tannous chloride =:n-l!> =see :ection 6 of Appendi 2> ". ".>? !:5.%=. =water mi ture %F*> and make the volume up to % l with addition of distilled water.> .4issolve ".4issolve ).*( . Available @hosphorus 8eagents requiredF i.a5?> of standard stock solution to *"" ml with distilled water =:ection . ii.""! =.=appro imately ) g1l> :tandard phosphate solution 4issolve ". .> ."! =. when diluted to *" ml volume for the development of phospho-mollybdic blue colour."!=. 4ilute !" ml of this solution to *"" ml to get ! ppm solution of @. -alculationF Available nitrogen =mg1%"" g soil> T =!* .! g of /$n5.)!( potassium permanganate =/$n5. 4istill the mi ture after adding ! ml of liquid paraffin and %"'%* ml of glass beads. sodium hydro ide . *. Find out the respective optical density readings by the help of a photoelectric colorimeter or a spectrophomometer and plot the readings against the corresponding concentrations of @ to prepare a standard curve. grade .@rocedureF :tandard curveF Take ".o. A@@D." ml !. -alculationF $oisture content =(> !.nitrogen free> . -rude @rotein 8equirementsF i. solution and shake for )" minutes with a mechanical shaker.42W 222 $ethods of Analysis of Feed and Feed 2ngredients %. Add !." ml and %". . -alculationF Available @ mg1%"" g soil T ppm @ in solution M !".* ml. Filter the suspension immediately on a #hatman . $oisture 8equirementsF @etridish 4rying oven <alance @rocedureF @lace pre-weighed . -oncentrated :ulphuric acid =A. The colour develops at its full intensity in )'. %." ml of sulphomolybdic acid in each. Take % g of air-dried and powdered soil sample in a glass bottle with stopper.8." ml of ! ppm solution of @ in *" ml capacity volumetric flasks.* ml. add !"" ml of ".'* g of the sample in a covered petridish and dry at %""'%"*Hin a drying oven till constant weight is achieved.! filter paper.""! =.> ?!:5. minutes and begins to fade after %"' %! minutes. $ake the volume up to *" ml mark by adding distilled water and add * drops of :n-l ! while shaking gently. Take !* ml of the clear filtrate and find out the concentration of @ in that solution through the standard curve. % .!*" ml @rocedureF Take e actly %. @otassium sulphate =A. i . i. iii.4issolve .a5?> solution while tilting the flask so that two layers are formed.8. grade ?-l with distilled water to make % l.ii.4issolve %." g of . ?ydrochloric acid =".itrogen content M &. 5n completion of distillation.%=.a5? pellets in %"" ml of distilled water. .Add * ml of indicator solution =". ?eat the flask gently at an tilted position till frothing stops and then boil until the solution becomes clear. vi."(> . -ool and add 7" ml of distilled water." g of sample into the /9eldahl flask and add %" g digestion mi ture which consists of potassium sulphate and copper sulphate in 7F% ratio and !" ml of sulphuric acid. .!* 2f you suspect mi ing of urea in the sample. then wash the sample thoroughly with distilled water and dry at &"H. vii.> ?-l.(> . grade> @araffin wa :odium hydro ide solution =.itrogen content of sample =(> -rude protein =(> T . v.%( methyl red and ". leave it for some time and add again !* ml of sulphuric acid and mi . remove the received and wash condenser tip and titrate against ". heat and collect distilled ammonia in *" ml boric acid1indicator solution. iv.!( bromocresol green in alcohol> to % l of saturated boric acid solution. g of sodium sulphide in %"" ml distilled water.before proceeding for protein estimation. -onnect rapidly to the condenser unit. :odium sulphide solution =.4issolve . To prevent bumping put small piece of boiling chips and add +" ml of sodium hydro ide =. ii. -alculationF . To control e cessive frothing add a small amount of paraffin wa .%& ml of concentrated A. @umic chips <oric acid1indicator solution .> . viii. -ollect the distillate.8. grade> $ercuric o ide =A.8. /9eldahl digestion and distillation units /9eldahl flasks =*"" ml cap> -onical flasks . ) g of dried sample either in an e traction thimble or in a silk bag. grade> with distilled water to make % l volume :odium carbonate @rocedureF . 2f the e traction is done by putting the material in pre-weighed silk bags and hanging in e traction flask then follow the following calculation. <y increasing the e traction rate the e traction time may be reduced. -rude Fat 8equirementsF @etroleum ether =<. ii. <enedict3s reagent &=. 8emove ether completely on a boiling bath and then dry the flask at %"*Hfor )" minutes. iii. iv. #eight of the crude fat T 2nitial weight of the bag with material .%"" mg in %"" ml of distilled water. -arbohydrate 8equirements F i.@. 5n completion remove the thimble. -onnect a dry preweighed solvent flask beneath the apparatus and add the required quantity of solvent and connect to the condenser."'&"H-> D traction thimbles1flasks :o hlet e traction apparatus @rocedureF Take !.& ml of concentrated ?-l =A. -ool the same in a desicator and weigh.iii. :tandard glucose solution . @lace the thimbles or the bag inside the so hlet apparatus1so hlet flask.4ilute &7. -alculationF #eight of the crude fat T Final weight of the solvent flask T 2nitial weight of the solvent flask.Final weight of the bag with the remaining material.>?cl . . iv. Ad9ust the heating rate to give a condensation rate of !') drops1 second and continue e traction for %& hours.8. -alculationF #eight of the crucible . add !* ml of &=. add % g of sodium carbonate and put some glass beads and titrate against standard glucose solution. Take * ml of <enedict3s solution in a conical flask.< g #eight of the sample . -alculationF Eolume of standard glucose solution required for * ml of <enedict3s reagent T A.ow the same volume of <enedict3s reagent is titrated against the hydrolysed sample solution. dry silica crucible and place in a muffle furnace at &""H.>?-l and heat in a water bath for ) hours at %""H-. . %. Ash -oncentrated . Again put the sample in muffle furnace and heat till white ash is produced.<-A T -g #eight of the crucible L ash .itric acid :ilica crucible $uffle furnace @rocedureF Take ! g of sample in a clean. -ool and add ! drops of concentrated nitric acid.for & hours. -ool and neutralise with sodium carbonate until frothing stops and centrifuge the solution at ! """ rpm for %" minutes or filter. Eolume of hydrolysed solution required for * ml of <enedict3s reagent T <.4g #eight of ash . Take the supernatant or filtrate and make upto %"" ml by taking enough distilled water. The titration must be done only in heated condition.Ag #eight of the crucible L sample .Take %"" mg of powdered sample and dissolve in !* ml of water.4-A T Dg . -ool the crucble in the desicator and take the weight. At -entre h.A@@D.%%! mm mesh size> for zooplankton. The plankton sieving net is the common equipment used and is made of bolting silk cloth . lay off angle a by means of a protractor and draw lines he and hf. !* =Z ".on a piece of paper. . mm mesh size> for phytoplankton and ."&. . %) =Z ".o. lay off the arc . @lankton Analysis 2nformation on the abundance and variations of natural fish food organisms is necessary for proper fishery management. the cloth may be cut and stitched and fitted onto a brass frame having wooden handle.of smaller circle. Asing %LW as radius. %. The plankton cloth is cut based on the following calculations.% -ollection of samples 2n fish ponds plankton samples are generally collected using a truncated cone shaped net by filtering known volume of water =normally *" or %"" %>. draw arc . #ith as radius.eaving % cm all along the sides.o.42W 2E $ethods of -ommunity :tructure Analysis %. $ethods of plankton analysis include collection of plankton samples and analysis of the samples both quantitatively and qualitatively. ) T )&.). the preserved plankton samples are analysed for quantitative and qualitative aspects.)H and 7" .) T %.6H Asually about *"'%"" % of water is filtered through the plankton net and the sample is preserved in *( formaldehyde.For he and hf. %. mark points at 7" L *).*).! Ruantitative analysis of total planktonF :ettling volumeF . 2n the laboratory. Transfer the sample to a graduated cylinder or centrifuge tube and allow sufficient time =at least &'+ hours> for plankton to settle at the bottom and record its volume and e press the volume as ml of plankton1% or ml of plankton1m . -entrifuge of the samples may also be resorted to, for quicker analysis. ) #et weightF The plankton sample is filtered through bolting silk cloth, e cess water is blotted out and the residual material is weighed. The wet weight is e pressed as mg1% or g1m water. ) 4ry weightF After taking the wet weight, dry the plankton samples in a hot-air oven at &"'+"H- for about si hours and take the weight on a sensitive balance. D press the weight as mg1% or g1m . ) ,umerical countF 4ilute the filtered sample to a known volume, say %" ml, and take for counting under microscope. :hake well the diluted plankton sample and take one drop for counting on a glass slide and cover with a cover slip or take % ml of plankton suspension in the :edgewick- 8after counting cell having a capacity of % ml with its area divided into % """ equal squares. -ount the number of plankters under microscope with %" and %" lenses. 2f %"" squares at random are counted, and %"" % water had been filtered, the number per litre will be given by W M %" M %"X%"", where W is the number of plankters. #hile only the larger plankters are counted in the Osurvey countP method, all the plankters are counted in the Ototal countP method. %.) Rualitative analysis of planktersF The Odifferential countP method is usually followed which requires enumeration of some or all kinds of plankters, distinguishing them qualitatively into species or genera of phytoplankton and zooplankton. :hake well the diluted plankton sample and take % ml of plankton suspension in :edgewick-8after counting cell or one drop on a glass slide and cover with cover slip and count following the method described for numerical count. 2nstead of counting the total number of plankton, count important groups of phytoplankton and zooplankton separately. 2mportant groups of phytoplankton usually encountered are green algae =chlorophyceae>, diatoms =<acillariophyceae>, blue-green algae =-ydnophyceae>, dinoflagellates =4inophyceae> and chrysomonads =-hrysophyceae>. Jooplankton in ponds mainly comprise protozoans, rotifers, cladocerans, calanoid and cyclopoid copepods and their larval forms and occasionally nematodes and ostracods. <ased upon the total counts, percentage composition of the different forms as well as phytoplankton and zooplankton as a whole may be calculated with their seasonal variations. !. Analysis of <enth Fauna !.% :ample collectionF • • 8andomly fi sampling points covering various zones of the pond. -ollect sediment samples with the help of Dkman dredge for deeper ponds while glass tubes =both sides openG 6'%" cm dia and )"'." cm long> for seasonal and shallow ponds. 2n case of sediment sample collection with tubes, the tube is gently placed on the sediment and then pushed further deep. The open end is then tightly closed with a rubber stopper and the tube is lifted up with the contents. The contents are emptied onto an enamel tray. Transfer each sample into a separate tray. 4ilute the sample with pond water, stir the sediment gently and pass it through seive. <:: ." =mesh size ".. mm for macrozoobenthos> or <:: &" =mesh size ".) mm for meizoobenthos>. 8epeat the process till the samples are completely washed. Transfer the sieved material to wide mouth bottles with little water in each and fi with %"( formaldehyde or 6"( ethanol. • • • !.! Ruantitative analysisF ,umerical methodF • • • Transfer the preserved samples into petridishes. :egregate the organism into ta onomic groups with the help of pipette1forceps and magnifying glass or stereoscopic microscope. -ount them as total or under various ta onomic groupings and calculate the abundance of the organisms per unit area as per the following equation. n T ,umber of macroorganism per sampled area a T Area of Dkman dredge or area of tube sampler h T ,umber of hauls constituting a sample Eolumetric $ethodF • • <lot dry the sample organisms with the help of filter paper and segregate them into ta onomic groupings. Transfer them to tubes calibrated at % ml intervals and add water from a burette drop by drop till the organisme is fully submerged in the water. :ubstract the amount of water added from the burette, from the test tube reading which will give the volume of benthic organism. -ompute the volume of benthic macro-organism per m as a whole or individual groupwise with the help of the following formula. ! • v T volume of macro-organisms1 sample a T area of the Dkman3s dredge1 area of the glass tube sampler h T number of hauls constituting a sample. Kravimetric $ethodF • • • <lot dry the samples group-wise on filter paper #eigh them in a sensitive balance =wet weight> 4ry the above samples in an oven at &"'+"H- to get dry weight =D clude the shell weight of the molluscs> ! The wet weight and dry weight of the benthos are e pressed in g1m . A@@D,42W E Fish ?ealth D amination 8ecords -ase ,o.F ;ocalityF :alient features of the water bodyF ;ength % mmF -onditionF D ternal e aminationF ;ookF -olourationF -heck for cysts, parasite <odyF FinsF :calesF 5perculumF DyesF $outh cavityF KillsF Dmaciated ,ormal 5ther if any spots, ?ealthy 4eeply pigmented [ lesions, and abnormality if any haemorrhages Fresh :poiled 8efrigerated #eight=g>F Frozen Fi ed 4ateF $icroscopic e aminationF -heck for cysts, :pores, abnormality, $ucous1:cales Fins Kills ;iver /idney :pleen 2ntestine $uscles Dye parasite, lesions, etc. bacteria inflamation A@@D,42W E2 -ommon 4iseases, Their :ymptoms and Treatment $easures DI/&-/& C-U/-TI;& -+&NT COMMON /KM(TOM / # TR&-TM&NT M&-/UR&/ ) 1 A. <acterial diseasesF %. -olumnaris disease Fle ibactercolumnaris 2 4iscoloured patches on the body, sloughing off of scales, erosion of gill lamellae, etc. -opper sulphate % minute dip in *"" ppm solution ".!*'! ppm in pond treat ment depending upon hardness of water. ?ard water requires more. @otassium permanganat e % minute dip in *"" ppm solutionG )'* ppm in pond treatment depending upon organic content. 5rganic rich water requires more. @enicillin L :treptomycin 2n9ection for brood stock at )"'." mg of streptomycin and !" """ i.u. of penicillin1 kg body weight prevents !. 4raining and liming the pond or treatment with bleaching . ?istologically hyperplasia. fusing of gill lamellae and 4ip in treatment of )( common salt solution or in *"" ppm copper sulphate solution or in *""'% """ ppm of potassium permanganate solution till the first sign of any distress. decreasing organic level in the pond. septicaemia> haemorrages and in severe cases the abdomen is swollen and the scales protrude.* g1%"" kg body weight1day for !') weeks. avoidance of over feeding. Fungal diseases %. -haracterize d by necrosis in the gill due to intravascular growth of this fungus. @ond treatment at )'* ppm of potassium permanganate is also a practical approach. :wabbing with %" """ ppm of potassium dichromate is also recommended. <ranchiomycos <ranchiomycesspp is 2mprovement in water quality. addition of freshwater together with treatment measures suggested above are quite effective.* g1%"" kg body weight1day for %"' %! days. 5vercrowding. Alceration or e foliation of the skin. warmer conditions and o ygen depletion are some of the contributing conditions to be avoided.* g1%"" kg1 day for %"'%! days. <acteremia Aeromonashydrophila. !.stress mediated outbreaks. paling of liver and sometimes heamorrhage s over swim bladder. Fura olidone at *'6. Terramycin =o ytetracycline> orally with feed at 6. manuring. 2nternally the body cavity is filled with opaque fluid. fin erosion. :aprolegniosis :aprolegniaspp.@seudomonasfluoresce :hallow =?aemorrhagic ns and possibly others ulcerations. e posure of muscles and 9aw bones and in some cases tufts of minute white hair like outgrowths may occur in the affected regions. <. Terramycin =o ytetracycline> with feed at 6. nursery and :everal other rearring pond antiprotozoan drugs are causing large also in use against this scale disease. ppm of malachite green fins. @rotozoan diseases %. gills. %*"'!*" ppm thick mucous of formalin. and !*'*" ppm of The parasite formalin can be used as can be prolonged bath. % sis =white spot disease> @resence of $i ture of malachite pin point size green and formalin at numerous several concentrations white spots are very effective. $y osporodios $y osporidiansp. <efore %. ". solution of sodium presence of chloride. :mear from gills and skin readily e hibits parasites with radial ciliary band and central denticles. ". Trichodinosis ! Trichodina sp.areas of powder is essential acute before initiating the ne t necrosis are culture operation.%* ppm is ciliated body very effective provided and that ) such applications horseshoe are made at ) days shaped intervals. -. surface.!* ppm of coat on the malachite green are affected very effective measures. Affected ponds should frayed fins be disinfected before and gills are ne t stocking. seen. 2chthyophthiria 2chthyophthiriussp. some of the common characteristic s. 4iscolouratio <athing in %'!( n of the body. @arasitic diseasesF %. Application of nucleus. %. mortality. etc. observed in :praying the entire pond skin smear by area with malachite its round green at ". @resence of 2nfected fish should be white cysts of immediately removed varying from the pond. ) is . The quick lime =-a5> at disease is higher rate in the pond common in is also very effective."* on the body. diameters on the body. gills. $onogenetic % trematode infection Kyrodactylussp. !. <lack spot ! disease 4iplostomumsp. !. several parts 8emoval of aquatic of the body snails and preventing and fins. 4evelopment Fish e hibiting black of small black spots may be given an or brown hour bath in %" ppm spots on picric acid solution. 2nfection cutis and does not spread from under lying fish to fish and hence it muscles. equally beneficial. 4ip in !'*( production of salt solution till the first mucous. is not worth treating $icroscopic uninfected stock. inititing the ne t culture operation the pond should be dried if possible and1or thoroughly disinfected with bleaching powder at *" ppm. and4actylogyrussp. @rovision of settling tank before the water intake in the pond also reduces the risk of infection. <ath skin ulcers or pond treatment with and damaged some soft gills. the entry of birds are :pecific some of the preventive locations are measures. sign of distress is frayed fins. is very increased effective. dark colouration together with presence of cysts and spores in kidney tissues without showing e ternal cysts. opercula. fins. organophosphorus $icroscopic insecticide is also observation equally effective. ?eavily <ath in %""'!*" ppm of infected fish formalin ranging from % show to ) hours. . 2n some cases. $etazoan disease !. emaciation. etc. of the skin lesion1smear and temporary mount of a portion of gill show the presence of the parasites. "! ppm a second patches over subsequent treatment the body and after a week. 8elatively they are not 8emoval of aquatic vegetation and !.eech infection @iscicola sp. . secondary infection as well as accelerate the healing process. 0uveniles are :ometimes embeded in the skin and cause mass hence remain mortality in unaffected. the author has parasite of % found very little to ! cm improvement by length potassium hanging permanganate outside. Argulosis ) Argulus sp. treatment. .e amination and dissection helps in locating rolled up and slowly moving worms embedded in the connective tissue. . -hlorophos carp nursery a 4iptre or . Anaemia. !.!* ppm kills all the parasite. $alathion also required a second treatment after a week interval. * .!* ppm in pond also effectively controls the infection.eraeasis . <aths in concentrated severe solution of salt and ulcerations potassium and presence permanganate is of attached reported to be effective. !. pond at ".%* ppm. Affected presence of fish should also be given the parasite dip in *""'% """ ppm in large potassium number in permanganate solution and around which helps in avoiding the lesion.ernaea sp. $alathion at ". cylindrical ?owever.eguvan and rearing when applied in the ponds. 4evelopment <enzene he achloride of application in pond at haemorrhagic ". <rome completely cures the infection when applied at ". ?ard ob9ects attachment such stones. 5perational activities . maintenance of pond They affect hygene is the most the fish by important preventive their measure. irritation and restlesness. through the 5rganophosphorus dermis may insecticides as be observed. solution is also very hyperaemia effective treatment. Attacked fish show attached parasite. 4ip and petechial in % """ ppm acetic acid haemorrages. The book-keeping system has the following two ma9or aspects of recordingF A.dangerous.42W E22 <ook /eeping <ook keeping is the core of fish farm management which records all aspects of fish farm operations and enable the fish farmer1farm manager or the e tension officer to understand the economics of the pond1farm operation. Area of 4isinfection of pond with attachment unslaked lime at ! *""' normally ) """ kg1ha should be e hibit done prior to ne t e cessive rearing operation. or %" """ ppm in 2nflamation potassium and epithelial permanganate solution hyperplasia are also quite effective e tending measures. are often infected by bacteria and fungi. A@@D. described in earlier 5pen wounds cases can also be used. provide information for planning developmental pro9ects and better services for fish farmers. They may attempt to rub against ob9ects. Account keeping <. logs. should also be removed. and also to provide necessary ground to get funding support from financial institutions. and feeding. etc. :hort mucous bath in )'*( salt production. %. .edger <ook =. 8eceived loan money from the :tate <ank of 2ndia. pond-wise or sectorwise separate entries should be made in the ledger book and in such cases separate pages should also be provided for each pond. etc. . A. -ash <ook =-<> 8eceipts always on left page of the -ash <ook R c ipts Dat 6.%7+6 -apital Acct.%7+6 5pening balance ) % (ag 15$ $ dg ! 9oo6 (ag No. Account /eeping $aintain ! thick bound registers one as -ash <ook =-<> and the other as .%.edger <ook =."" @ayments always on right page of the -ash <ook . there should be separate pages for each pond. !. . <hubaneswar +.umber all pages of the . This will give a complete record of everything you spend and any money you receive.<>.<> and keep at least one page for each item as shown by giving e amples of + pages. %. To analyse the performance of individual sector or a particular pond of the farm.umber of pages for each item depends on the e tent of recurring e penditures or receipts under that head."" ! *""."" ! %"&.o."" %*". Accordingly.umber the pages in -ash <ook keeping the same page number for both right and left facing pages. entries should be made under fish sale of pond . /eep left pages for receipts and right pages for payments. enough page space should be kept under that head so that it may cover a period of % year. Accordingly. -mount 0U/D2 (a!ticula!s o' ! c ipts ! *"". % or Fish sale of pond .A simplified form of this system is described which can be used by fish farmers1fish farm managers and e tension workers.%7+6 5pening balance =5<> :ale proceeds =fish> 8eceived towards sale of %"" kg of unwanted fish at A:V %.*"1kg ! after bleaching powder application :ale proceeds fingerlings 8eceived towards sale of *" """ fingerlings of catla at A:V !""1% """ 7. for fish sale.o.%. Dnter the details of receipts and payments on daily basis in both of these registers."" %" """. -alculate closing balance =-<> for the day which will become opening balance =5<> for the following day. For e ample."" % """."" %% %*". (aym nts Dat 6.%.%7+6 (ag 15R $ dg ! 9oo6 -mount 0U/D2 pag No. . * TotalF % """."" *""."" % *""."" ! *""."" (a!ticula!s o' 4p nditu! @ond -onstruction -onstruction of one nursery pond $aintenance of @ond 8epair of dyke of stocking pond ,o.6 -losing balance % """."" +.%.%7+6 ;abour -harge ! labourers for pond poisoning at A:V !"."" per labourer1day @iscicide %"" kg of bleaching powder at A:V ..""1kg TotalF 6 .""."" .."."" ! *"&."" & ."."" -losing balance ! %"&."" !. ;edger <ook =;<> Capital Dat (a!ticula!s (ag 1 C9 pag No. % D 3it C! dit -mount -mount 0U/D2 0U/D2 ! *""."" 6.%.+6 ;oan money from :tate <ank of 2ndia, <hubaneswar <ranch Fish /al Dat (a!ticula!s (ag 2 C9 pag No. % D 3it C! dit -mount -mount 0U/D2 0U/D2 %*"."" +.%.+6 %"" kg of unwanted fish sold at A:V %.*"1kg ;edger <ook =;<> F!y /al Dat +.%.+6 (ag # C9 pag No. D 3it -mount 0U/D2 C! dit -mount 0U/D2 %" """."" (a!ticula!s :ale of *" """ catla fingerlings at !""1% % """ A:V (ond const!uction Dat (a!ticula!s % (ag ) C9 pag No. D 3it -mount 0U/D2 % """."" C! dit -mount 0U/D2 6.%.+6 -onstruction of one nursery pond ;edger <ook =;<> Maint nanc o' pond Dat (a!ticula!s (ag , C9 pag No. % D 3it -mount 0U/D2 *""."" C! dit -mount 0U/D2 6.%.+6 8epair of pond dyke of stocking pond ,o. 6 Maint nanc o' pond Dat +.%.+6 (ag . C9 pag No. D 3it -mount 0U/D2 ."."" (a!ticula!s C! dit -mount 0U/D2 ! labourers for application of bleaching powder for % pond poisoning at A:V !"."" per labourer ;edger <ook =;<> (iscicid Dat +.%.+6 (ag 8 C9 pag No. % (a!ticula!s %"" kg of bleaching powder e A:V ..""1kg D 3it -mount 0U/D2 .""."" C! dit -mount 0U/D2 Fish F Dat 2tem @resent d C9 pag No. D pected (ag @ D 3it -mount 0U/D2 Annual (a!ticula!s C! dit -mount 0U/D2 $onthly ). Annual <alance :heet An Annual <alance :heet form should be prepared after a year of farm1pond operation which will show how much is earned and what the fish farm is worth. 2t makes a summary of everything that has been recorded in cash book =-<> and ledger book =;<>. $ake total of every item in the ;< and put it in the Annual <alance :heet. 2f required $onthly <alance :heet can also be prepared taking monthly total of every item, from the ;<. .. 4epreciation -ost 4epreciation cost is the amount of value an e pensive item loses every year and this amount one must keep aside to replace the item when it is worn out. To work out depreciation cost for any item, for e ample a pump set, one should consider the following two aspectsF i. ii. #hat would be its e pected life\ :ay %" years #hat is the present value\ For each such item put these two figures in respective column in the following form and calculate annual or monthly depreciation cost. It m 0-ss t2 (! s nt cost &4p ct d li' -nnual d p! ciation Monthly d p! ciation @ump set ,et V % """ V *"" %" years & years V %"" V +).) V +.)) V &.7. %.) Annual <alance :heet IDA8 [ Month Cost o' (!oduction N t /al s Incom Incom > $a3ou Fis Fis Fis (ond5'a!m Maintainan Tota ! (iscici h h /pa! h Tota const!ucti c o' l cha!g d s ' s tc. s l on pond5'a!m Fish s d d d 0anuary February $arch April $ay 0une 0uly August :eptemb er 5ctober ,ovemb er 4ecemb er N ,et 2ncome T :ales 2ncome - -ost of @roduction *. ;oan Accounting A separate loan record sheet should also be maintained if the farmer has taken any loan for fish farming. For e ample, if the farmer has taken a loan of V *"" from the Kovernment for pond construction and that has to be repaid in %" years with an annual interest rate of %"(, with the assistance of the D tension 5fficer, the fish farmer should keep a record of his loan repayment. The interest paid on the loan should be regarded as a production cost and should be taken into consideration in calculating the net income of the fish farming operation. A simple loan record sheet is given belowF $oan 1 /ou!c 7 4ate [ Amount[ @eriod of repayment[ Annual rate of interest[ $oan 2 /ou!c 7 4ate[ Amount[ @eriod of repayment[ Annual rate of interest[ /tat 9an6 o' India Mu=a''a!pu! 9an6 o' IndiaL Mu=a''a!pu! R paym nt D tail Dat Int ! st $oan $oan Dat (aym nt R paym nt Outstanding R paym nt D tail Int ! st $oan $oan (aym nt R paym nt Outstanding TotalF <. 5perational Activities Aspects pertaining to the description of the ponds1farm, plan of work, operational activities such as prestocking, stocking and poststocking operations, monthly sampling details, harvesting, induced breeding, fish seed rearing, etc. should also be recorded. Formats, with e amples, for recording such activities are presented hereunder. %. @ond 4escription @ond clearing !. @re-stocking operationsF (OND NO.* %" 8ain ) %1! 8earing of fish seed !"" ". . common :ilver carp. :tocking detailsF (OND NO.4 . -ulture of ) 2ndian ma9or carps ) . grass carp."" kg1ha ) """ %. Age=years .@5. /TOCGIN+ D&T-I$/ 1 2 .iming .* %* 2rrigation canal ! . O(&R-TION/ %.A. carp & """1ha -owdung Fish feed %! months & million1ha @oultry manure $icro-encapsulated feed ) weeks ). silver carp.. Dradication of unwanted fish ).4 . Type of farming :pecies :tocking density $anuring Feeding @eriod of rearing % -omposite fish culture ! Fish seed rearing -atla.5. grass carp. 4D:-82@T25. rohu. FA8$2.6 + 8ain Average annual @roduction rate * *"" kg1ha #ater depth =m> :ediment depth =cm> #ater source !.ature of earlier operations if any @ond area =m > ! % * -omposite fish culture ! """ !.. Farming planF @5.5. 5rganic manuring 1 #eed clearing using manual method @oisoning-!*" kg of bleaching powder applied in the pond at *" ppm 2 #eed clearing using weedicides @oisoning-% %!* kg of mahua oil cake at !*" ppm &" kg of lime at !"" kg1ha .K @. mrigal. +1%+ 1. :pecies ratio &. :eed treatment 6. :ilver carp =:> .4 .%".12.%%. :pecies stocked ).!1%& ..sium permanganate solution --*"G 8-&"G $-*"G :-. @ost-stocking operationsF @5. 8.T?F 4D-D$<D8 %7+& . :tocking density . rohu =8>. 4ate of stocking !.!G 8 )G $ %. % $5. -59 6"1!" &"1!" ."1+ )"1+ )*1%* .+1%+ **1!" &"1%+ &*1%6 2.4 ..G 8 )G $ ) :hort bath in !( salt solution --*"G 8-&"G $-*" *. $rigal =$>. -ommon carp =--> & """1ha % !"" .+& -atla =->.%.* :hort bath in potas. Average weight =g> %*.%. $onthly sampling details =growth>F D-T& /(&CI&/ -atla 8ohu $rigal :ilver carp Krass carp -ommon carp *"1%" .5. MONTH O(&R-TION/ 5rganic manuring . $ carp =K>.umber stocked *.1."G K-*"G ---)" * """1ha % *"" . :tanding crop of fish =estimation> @5.5.+& %".@8 -59 6. -.@.*G : %.iming 2norganic fertilizer Feeding $edication No* m3 ! D c m3 ! Octo3 ! &.*G K ".*G -. Krass 8. . @5. 2nduced breedingF D-T& /p ci s W ight Inducing / ts /pa%ning &stimat d R ma!6s . ?arvesting details =Fish seed rearing>F (OND NO. harvested :urvival =(> Average weight =g> Total weight =kg> :pecies -ontribution ( Kross @roduction =/g> T Total weight of harvest =/g> .4 .. ?arvesting details =Table size fish production>F @5. !).* *"..o. Wt.) %" !" +.2nitial stocking weight =/g> 7. ha!* st d /u!*i*al B -*.) %&+. )).. ( !iod o' ! a!ing 0days2 /p ci s No. stocked . Wt./p ci s -atla 8ohu $rigal :ilver carp Krass carp -ommon carp Total -*.4 :2JDF 4ATDF /(&CI&/ D&T-I$/ Catla Rohu M!igal /il* ! ca!p +!ass ca!p Common ca!p Total .o.) %%.. stoc6 d !. R ma!6s 0g2 %"." )&" %+" %+" &" %+" % !"" - Mo!tality %" Total % ight 06g2 ). attain d 0g2 %*" %.et @roduction =/g> T Kross production =/g> ." %)" %+* %7" 7" No.5. %*. ylon material with aluminium1cane framing open at both ends .& @lastic tub1galvanized iron sheet tub1 fibreglass circular tank. 6.%" pieces =$esh size should be measured knot to knot diagonally> !.%" pieces !" mm meshed =%" m M & m> . &. sinkers and floats. ?and net =:coop net> of !* mm mesh . +.2 succ ss 0B2 No.* closed at distal end ..* :pade <ottom raker :ickle -* -! -& .* ). ." mm meshed =%" m M & m> . @lastic or enamel trays . 7.42W E222 Dssential 2tems for a Farm =:elf :ufficient * ha Anit> A. Table size fish farming sectorF %. :pring balances of the following capacitiesF % kg Q ! 4ial type * kg Q ! 4ial type !" kg Q ! . . o' spa%n A@@D. foot rope. @lastic buckets with lids of the following capacitiesF !l'& *l'& %! l ' & !* l ' ! *.ylon seive net pieces with head rope.0g2 ag nt Dos 0mg56g2 Mal F mal att mpt d 0No. Feeding tray =galvanized iron sheet> =*" cm M %"" cm M %* cm> ).%"" . -rowbar %).%".!"" . :pare gunny bags !7.<arbed wire !).% kg .%" . Fish :eed @roduction :ectorF 2n addition to the items listed under A.. .* rolls . -! . -onditioning hapa =cotton> !*. Ambrella )".& pairs -! .!" -% <.ylon twine =assorted size> !. Kum boot )!. mm meshed =%" m M * m> !.. <amboo hanger for drying the net !%.%" -% .!" -.Anfinished bamboo .ylon seive net pieces complete with head rope. 8ope of various sizes %*. @ick-a e %%. Anti-poaching devicesF . ?and net =scoop net> with opening at both ends and having a thick twine at the distal end for tying.* mm meshed =%" m M * m > ) mm ' . sinkers and floats %. $ini tractor operated compressor -! -& -. Kenerator set to be driven by * ?@ diesel engine %+.. <amboo baskets =*" kg capacity> !6.<amboo poles . !* mm meshed nylon netting . 8ain coat )%. Towels !&. ?ammer %. -ane baskets !!. Fish measuring board )). foot rope. -% -% -% -% -% . %. Krass cutting knives %!.%! -! -* .% roll each -. $ini tractor with trailer !". Torches =) celled> %&. . * ?@ diesel pump set with generator set attachment option %6.%" -. . !"" kg capacity balance with tripod stand and set of weights !+. :mall boat %7. -& . the following items are also needed. %" -& . Dnamel tray %!.%! .%*" .*" ml capacity %"" ml capacity !*" ml capacity !). -entrifuge tubes graduated %7.o. @ituitary gland !6.%"" .! cc capacity * cc capacity !*.%" .*" -% -. =%" """ mg> .. -entrifuge machine =hand operated> %+.ylon hatching hapaF 5uter 2nner &. Tissue homogenizer !!. Folding chairs %&. Folding work table %*.%" . -anvas strechers with provision of net cover for brood fish transport in the farm .!" ..ylon breeding hapa *. !" .*" .o. Absolute alcohol !+. -lean homoeopathic tube with stopper !.!"" -* -* .% """ nos. Dnamel basins )'* % capacity %). ?ypodermic syringes .%" .%" .%" .*" ml M ! .%! . -heesecloth for holding brood fish 7.) mm ' . 4ropper with long nozzle !%. Feathers %.! . @lastic buckets graduated %l *l %! l %". <eaker . @lastic1enamel mug graduated %%.! kg -*m .!"" ampoules . -! -% . <amboo poles 6.% each ).%" .. . !! !&.!" -* . !% . 4istilled water =sterile> !7. ?ypodermic needles . !*. :pawn measuring cup %".%! .!" .%" .%" .. *" ml capacity -* . :et of dissection instruments %6. 0ute or cotton twine +.o. . @etridishes =assortment> !". mm meshed nylon1cotton netting . " cm M * mm> .%" rolls1* """ nos.*.). -. ?owever. feeds.%" .) .. Thermometer ="'*"H-> ).! each -! -! .%.! kg -! -! )!.".!. @orcelain pestle and mortar =*'%" cm dia> .!" -% -% . *"" ml )%.* kg -! . -otton wool . $edicine -hest . -athetors =!.ime To avoid storage loss of nutrients and spoilage.". 8ubber cushion =&" cm M . :trainer cup for measuring fry %"" ml. <utcher3s knife )7. @lastic bags1cylindrical rolls thickness ". glass appliances =assorted sizes> )*. @iscicides. 5 ygen cylinder with regulator pressure gauge and dry o ygen gas )). Acetone . plastic. -. ?igh power hand lense )6. 4esicator with silica gel . manures and fertilizers • • • • • • • • • • • <leaching powder1mahua oil cake 8ice polish Kroundnut1mustard oil1soyabean cake $ineral mi ture Fish meal 8aw cow dung1poultry manure1pig dung Area Ammonium sulphate :uper phosphate $uriate of potash . weeks.. -otton twine for tying the o ygen packed bags )+.* mm dia> .)". it is desirable to buy the items on regular basis. :tereoscopic microscope with stage lightning )&. the store should have sufficient amount of ready stock of these items so that they may last for )'..*" ml M ! -! -! .* mm circumference %""'%*" mm .. The selection of items also depends upon the local availability and relative market prices. #idemouth bottle with glass stoppers . <rushes for cleaning metal. :odium choride =common salt> -opper sulphate @otassium permanganate 5rganophosphate insecticide =$alathion1:omithion> <enzenehe achloride =<?-> wettable powder Formaldehyde =formalin> Acetic acid =glacial> Ruick lime <leaching powder =sodium hupochlorite> 5 ytetracycline @enicillin :treptomycin $alachite green =zinc free salt> .*"" ml M %" .%"" g M %" .%" l M % .* kg .!* kg M %" bags .%" g M * .%" vials .*" kg M * packs .*"" g M %" -%lM* .* kg .*"" g M %" packs .%" vials .