Broodstock management for carp seed production ppt

The fisheries students all over the world can see my presentation on broodstock management for carp seed production,

1. BROOD STOCK MANAGEMENT FOR CARP SEED PRODUCTION Submitted by : Mrutyunjaya Ghadai (8F/16 ) Swagatika Sahoo ( 29F/16 )

2. Topics to be covered .. Introduction Objectives of broodstock management Importance of broodstock management Selection procedure of brood fish Source of broodfish Management of broodstock ponds Feeding management Care of broodstock during prespawning,spawning and post spawning phases Problems during brood stock management Preparing future broodstock

3. INTRODUCTION Three Indian major carps viz. catla (Catla catla), rohu ( Labeo rohita ) And mrigal ( Cirrhinus mrigala ) being an excellent edible fish as they grow faster than other indigenous carps. Together these carps account for approximately 75 % of the total inland aquaculture production in India. Production of fish seed of many fish seed farms throughout India is poor due to improper broodstock management practices. Nutrition is known to have a profound effect on the reproductive performance of fish . Brood Fish means the mature parent fish that is usually used in hatchery for breeding purpose . Brood Fish is a fish that is mature enough to give egg and sperm and are usually large in size. Generally 2-3 years of old fishes weighing about 2-3 kg are used as brood fish. Brood fishes usually show gonadal maturity to give sperm or ovum . Brood fish management means the act of running and controlling of brood fishes by manipulating environmental factors.

4. Objective of Broodstock Management To ensure the proper care and management for the brood fish . b) To product available fry by using same fish two or more times within a year by artificial reproduction . c) To ensure develop culturable fish production by proper management . d) By using selective and line crossing method we can solve the problem of production of develop fish species intra reproduction.

5. Importance of Broodstock Management ● Broodstock management is important because proper brood fish management gives quality egg and sperm . ● Broodstock management is one of the most important parts of aquaculture and ensures successful aquaculture . ●Proper broodstock management decrease the larval or fry mortality and increase production and gives huge amount of stronger and disease free fry and larvae . ● If the brood fishes are properly managed, it will remove the inbreeding problem . ● Proper brood fish management is the key to success of induced spawning . ● Proper brood fish management increases the fecundity of egg and sperm and also gives rapid growth of larvae, fry at first and later the fishes. ● By proper management of endangered brood fishes, it is possible to save endangered fish from extinct. ● Brood fish management gives the supply of fry, larvae at appropriate time and at a low cost .

6. Broodstock management covers three particular aspects of the rearing process : The selection of fish with desirable hereditary qualities typical of improved strains such as rapid growth potential, higher resistance to dissolved oxygen deficiency and adverse water quality, strong appetite, omnivorous feeding regime. ( b) The selection of fish with well-developed sexual organs . (c) The rearing of these selected fish to produce healthy potential spawners , with dormant eggs well developed in the females . Characteristics of Good broodstock Better breeding responses Increased fecundity, fertilization, hatching Increased larval survival rates More viable fish seed

7. Selection Characteristics and Procedures Female A bdomen is soft and bulging. Smooth pectoral fin. The genital opening is swollen, protruding and pink to reddish in colour; its edge is often uneven of fringed . The vent region may also be swollen and reddish . And the vent of fully ripe female is slightly elevated. Males Dorsal surface of the pectoral fin is to be rough . A mature male releases a few drops of milt when its abdomen is pressed slightly. Abdomen is smooth and not bulging. Fig .female (left) male (right)

8. SOURCES OF BROOD FISH source of brood fish is stock ponds from the same farm or different farms or live adult of different species procured from capture fishery waters like rivers, lakes or reservoirs . In commercial carp hatcheries the main problem is the inbreeding depression and genetic drift due to the breeding between offsprings of same parent or between parents and offsprings.So fishes are transported to the hatchery . Transport of bigger fingerlings/yearlings and broodfish in Trucks mounted open tanks with facilitates for mechanical aeration and/or circulation were used quite successfully .

9. Management of broodfish ponds Improving water quality improves the development of natural food and stabilisation of water characteristics that do not stress the fish and this favours good gonad development. Basic factors of water quality to be measured with regards to effective broodstock maintenance are oxygen , temperature, pH, and alkalinity. By knowing pH and alkalinity it is possible to know the necessity and importance of liming . Fish will be more or less stressed and will not develop their potential if: • pH is low (less than 6.0) or varies greatly • Oxygen content is low or varies greatly • Temperature varies often or is above 30°C, due to shallow ponds.

10. Carp broodfish pond : large ponds (0.2-2.5 ha), 1.5-2.5m deep, rectangular, seasonal or drainable and earthen in nature . Water inlet and outlet is given in ponds to simulate riverine/fluviatile conditions . Females and males are preferably kept in separate broodstock ponds. Two sets of ponds are used for the ripening males and females, and two sets of ponds are used for the spent spawners . This will prevent wild spawning. It will also enable higher protein feeds to be distributed to the females, and to lower the stocking rates . Recommended stocking density of carp broodfish is 1,000-3,000 kg/ha

11. Common carp demand their separation from other carp species due to their natural breeding in ponds with aquatic vegetation The common carp broodfish is segregated sex-wise and stocked in separate ponds to prevent accidental spawning in pond Catla , in particular, needs to be separated from the rest of the species as it shows poor response to hormonal injection when stocked with other species It is believed that catla broodfish need special care and diet such that deposition of mesenteric fat in the maturation phase does not hinder gonadal development of the species.

12. Pond preparation Old ponds must have been completely drained to remove any fish. If full drainage and drying of the pond is not possible, the most appropriate way is probably to treat the pond with derris root powder or mahua oil cake @2000-2500kg/ha to kill all fish . Liming Liming is necessary if pH is less than 6.5 or if the alkalinity is less than 75 mg of calcium carbonate. About 100 mg of calcium carbonate per litre of water is a good level to maintain in the pond. pond liming at 100-200 kg/ha depending on the pH of soil and water 2 . MANURING Manuring should be done at least a few days after liming. Manuring is necessary and sufficient to provide the various kinds of carp, silver barb and tilapia with natural food. Use of chemical fertilisers is not so favourable , because common carp, mrigal and rohu feed mainly on pond bottom. Manure on the pond bottom will serve directly or indirectly in their feeding . Inorganic fertilisers can however reinforce the effect of manuring . Fertilizing the pond with cattle dung, at 15,000-20,000 kg/ha/ yr or poultry manure at 5,000-10,000 kg/ha/ yr to enhance heterotrophic food production 200-400 kg/ha/ yr NPK mixture is applied in split doses at fortnightly or monthly intervals Unlike manure, chemical fertilisers like urea must be applied after the pond has been filled with water.

13. POSITIVE EFFECTS OF POND LIMING ON POND BOTTOM ON POND WATER Soil structure is improved pH increases and is more stable Organic matter decays more quickly Alkalinity increases and more carbon dioxide is available for plants Soil pH increases More calcium is available for greenwater Some substances toxic for fish are neutralised Nutrients are released more quickly into the pond water Excess organic matter is settled to the pond bottom Fish are less stressed, gets more oxygen and natural feed and grows better and quicker

14. FEEDING MANAGEMENT OF BROOD FISHES After stocking the pond with carps that are one-year-old or more, they are fed with a conventional feed containing a mixture of groundnut oil cake and rice bran (1:1 or 1:2 ratio) at 1-2% b. w., once daily To ensure better and timely development of gonads, fish breeders use a special broodstock diet (protein : 25-30%) prepared using locally available cheap ingredients This diet is nutritionally superior, advances maturation and spawning by one or two months and results in increased fecundity and better seed quality . Carp broodfish fed with a traditional diet consisting of rice bran and oil cake (1:1) at a feeding rate of 1-2% body weight daily. This diet is given at 2% b.w. daily, starting in December

15. ( 1) Later, when the dormant eggs have been developed and when the breeders await spawning, they should receive artificial feeds with a 30-40% protein content in order to prevent the accumulation of fat in their gonads. 2) After stripping, when the breeders form new eggs which develop toward the dormant stage, they should eat a mixture of 50% natural food organisms rich in protein and 50% artificial feeds with a high content of carbohydrates, such as maize. In addition to the artificial feed the grass carp is also given tender aquatic weeds/terrestrial grass . At some farms about a third of the broodstock will be injected with a low dose of HCG at 6-7 mg/kg body weight every 20 days, starting from mid-February for advancing maturation so as to induce spawning by the end of May At some seed farms, a few vitamin E tablets are mixed, in the diet to facilitate gonad development

16. MAKING FEEDING EFFICIENT In order to feed enough but with minimum wastage, some simple methods can be used . The weight of broodfish stocked should be known with sufficient precision . samples should be made for calculating the biomass stocked in the pond . Feed the fish 2 times a day, in the morning and evening. In case of cool temperature, you may delay or cancel the morning feeding session because the fish may not be active.

17. CARE DURING THE SPAWNING PHASE 1. BEFORE SPAWNING Fish are concentrated in a corner of the pond by seining. Breeders are selected one by one. Fish ready to spawn are sent to the hatchery. The ones not yet ready are released in the pond and any wounded or sick fish can be removed and sold . During the sorting, fish left in the pond may suffer from a lack of oxygen. Aerators should be used for increasing oxygen content . Fish awaiting spawning must be kept in tanks with a permanent flow of clean well-aerated water.Tanks should be covered by nets for preventing fish from jumping out of the tank.

18. Fig.1 sorting of fishes ready to spawn Fig.2. selection of milters and spawners

19. SPAWNING Females to be injected should be held on a piece of soft foam or on a wet cloth during operation. Small fish can be injected whilst holding in a shallow basin half filled with water. One person should catch, weigh, hold and release the fish while a second person should inject . For dry stripping the fish should be held in a damp cloth to minimise damage. CARE AFTER SPAWNING After the spawning session, spent fish should be transferred to a “rest and recuperation” pond aimed at resting the broodstock for the next 2 or 3 months. This pond should not contain any broodfish that must be spawned in the following months so that no seining has to be performed. Restocking spent broodstock with nearly mature ones would result in heavy stress and injuries and likely loss of fish due to repeat seining. By putting spent fish together (and if possible sex-separated), it is also possible to feed them an energy rich diet ( e.g rice, cassava, potatoes) for getting back the weight lost during reproduction.

20. Fig. handling of broodfish Fig. care taken during injection Fig. disinfection of brood fish with kmno4 to avoid infection

21. PROBLEMS IN BROODSTOCK MANAGEMENT Algal blooms and oxygen depletion -common problems in broodstock ponds Overcome by frequent water exchange Infestation by Lernaea and Argulus on catla are common - manual removal of adult specimens, followed by a dip treatment in a mild solution of potassium permanganate Fig. lernaea Fig . argulus

22. PREPARING FUTURE BROODSTOCK Future broodstock selected at the farm should be selected early from the fingerlings available rather than from the commercial stock. Such fish can be stocked together with mature female broodstock that are fed the best diet in the farm. This will allow an optimum development of the gonads . Fish grown for commercial purpose are more poorly and unequally fed and their gonad development may be poorer resulting in a lower fecundity for a similar weight . If common carp must be selected, they must be selected amongst the first batch of the season (fry produced in February-March) if the objective is to breed them the next year. This may be difficult, as the manager must usually keep the fry a minimum of time in early rainy season because this is the peak season for reproduction . It is easier to nurse the last batch of fry produced in June or July since nursery ponds are available for the cold season. There is however the risk that late maturing fish are selected and that it may become with the time more difficult to have early maturing broodstock .

23. THANK YOU