FISH BREEDING TECHNIQUES
I. PRE-BREEDING
Brood Fish Care
i) STOCKING
PARTICULARS
Brood fish should be raised and maintained with the stocking rate of 400 to 500 kgs/acre. It is preferable to stock 400 kgs fish/acre. Different species of fish should be kept in different ponds.
Brood fish should be raised and maintained with the stocking rate of 400 to 500 kgs/acre. It is preferable to stock 400 kgs fish/acre. Different species of fish should be kept in different ponds.
REMARKS
Availability of quality brood stock has a pivotal role in the successful operation of a hatchery. As such healthy stock should be selected and greater attention be focused towards maintenance of proper hydro-biological condition to ensure sustained growth.
Availability of quality brood stock has a pivotal role in the successful operation of a hatchery. As such healthy stock should be selected and greater attention be focused towards maintenance of proper hydro-biological condition to ensure sustained growth.
ii) FERTILIZATION
PARTICULARS
Bed manuring of the brood stock ponds be carried out with 4000-5000 kgs per acre organic manure (cowdung) prior to water filling and such ponds be periodically fertilized to maintain productivity to desirable extent with 1000-1500 kgs organic manure & 8 kgs Inorganic fertilizer per acre per fortnight, subject to qualitative and quantitative fluctuations of plankton level.
Bed manuring of the brood stock ponds be carried out with 4000-5000 kgs per acre organic manure (cowdung) prior to water filling and such ponds be periodically fertilized to maintain productivity to desirable extent with 1000-1500 kgs organic manure & 8 kgs Inorganic fertilizer per acre per fortnight, subject to qualitative and quantitative fluctuations of plankton level.
REMARKS
Preferably when the water temperature ranges between 25-32°C.
At the time of shifting of brood fish treatment with sodium chloride or KMNO4 (Potassium permagnate) be given.
Preferably when the water temperature ranges between 25-32°C.
At the time of shifting of brood fish treatment with sodium chloride or KMNO4 (Potassium permagnate) be given.
iii) SUPPLEMENTARY FEEDING
Supplementary feeding of brood stock should be done with Rice polish, Maiz glutin and Mollasses in the ratio of 7:2:1 at the rate of 2-3% body weight of stocked fish per day.
Note: Brood stock of grass carp be fed with green fodder (Chatala, Barseen etc.) daily as per the requirement of fish.
II) BREEDING
i) Selection of Brood Fish
Brood fish selected at the time of induced spawning should be healthy and fully ripe.
ii) Sex Ratio
Male : Female = 1 : 1
iii) Hormone Dosage (Ovaprim)
It is to ensure breeding without fail and improve efficiency in breeding results.
| Fish Species | Total dosage of Female | Total dosage of Male | Remarks |
|---|---|---|---|
| Ctenopharyngodon idella (Grass carp) | 0.6 – 0.7 ml/kg | 0.1 to 0.2 ml/kg | In case of proper maturity of brood stock preferred dose should be 0 – 6 ml/kg for male & 0.1 ml/kg for female. Fertilization is executed only through stripping after 10–12 hours of hormone injection. |
| Aristichthys nobilis (Big head) | 0.6 – 0.7 ml/kg | 0.1 to 0.2 ml/kg | –do– |
| Hypophthalmichthys molitrix (Silver carp) | 0.6 – 0.7 ml/kg | 0.1 to 0.2 ml/kg | –do– |
| Catla catla (Thaila) | 0.5 ml/kg | 0.1 ml/kg | –do– |
| Labeo rohita (Rohu) | 0.3 – 0.4 ml/kg | 0.1 ml/kg | –do– |
| Cirrhina mrigala (Mori) | 0.3 – 0.4 ml/kg | 0.1 ml/kg | –do– |
III) POST BREEDING
Incubation
i) Circular tank
PARTICULARS
a) Quantity of eggs – 8,00,000 to 10,00,000 lacs in a tank of 5 cft dia.
b) Water supply – water in circular tank to be arranged between 22–25 litres per minute.
c) Screen – central exit pipe to be fitted with bolton or nylon cloth, mesh number about 4200 per sq. inch or slightly above.
a) Quantity of eggs – 8,00,000 to 10,00,000 lacs in a tank of 5 cft dia.
b) Water supply – water in circular tank to be arranged between 22–25 litres per minute.
c) Screen – central exit pipe to be fitted with bolton or nylon cloth, mesh number about 4200 per sq. inch or slightly above.
REMARKS
Proper water flow and fine screening are essential to ensure uniform egg circulation and to prevent loss of eggs or fry through the outlet.
Proper water flow and fine screening are essential to ensure uniform egg circulation and to prevent loss of eggs or fry through the outlet.
ii) Mc. Donald Jar (Glass Jar)
PARTICULARS
a) Water supply – each Mc. Donald Jar regulated with about 1–1.5 litres per minute.
b) Quantity of eggs – about 15,000–20,000 eggs per jar.
a) Water supply – each Mc. Donald Jar regulated with about 1–1.5 litres per minute.
b) Quantity of eggs – about 15,000–20,000 eggs per jar.
REMARKS
Gentle upward water flow keeps eggs in suspension and improves hatching percentage; excessive flow should be avoided.
Gentle upward water flow keeps eggs in suspension and improves hatching percentage; excessive flow should be avoided.
Nursing of Hatchlings
PARTICULARS
Following is duration period for nursing of hatchlings till these become first feeding larvae/fry. Feeding of yolk fry should be avoided.
Following is duration period for nursing of hatchlings till these become first feeding larvae/fry. Feeding of yolk fry should be avoided.
| Hours | Water Temperature |
|---|---|
| 72 – 80 | 27 – 28°C |
| 80 – 96 | 25 – 27°C |
REMARKS
Fry is ready for stocking when the air bladder is formed and the yolk sac is almost absorbed.
Fry is ready for stocking when the air bladder is formed and the yolk sac is almost absorbed.
Preparation of Fry Ponds
PARTICULARS
i) The pond should be sun dried before the breeding schedule is commenced.
ii) The pond should be fertilized with organic manure (cowdung) @ 4000–5000 kgs/acre subject to qualitative & quantitative fluctuations of plankton level.
iii) Fill the pond with water to a depth of 1.5–2.0 feet and maintain it.
iv) Observe the production of micro fauna after about 48 hours of fertilization.
i) The pond should be sun dried before the breeding schedule is commenced.
ii) The pond should be fertilized with organic manure (cowdung) @ 4000–5000 kgs/acre subject to qualitative & quantitative fluctuations of plankton level.
iii) Fill the pond with water to a depth of 1.5–2.0 feet and maintain it.
iv) Observe the production of micro fauna after about 48 hours of fertilization.
REMARKS
To ensure dis‑infection of pond soil the pond must be well dried before filling.
Dry manure is preferable; fertilization should ideally be done the day fertilized eggs are obtained.
At a temperature of 25–32°C, after 48 hours of fertilization protozoans and rotifers begin to appear; after about 72 hours first food (protozoans and rotifers) becomes fairly abundant.
To ensure dis‑infection of pond soil the pond must be well dried before filling.
Dry manure is preferable; fertilization should ideally be done the day fertilized eggs are obtained.
At a temperature of 25–32°C, after 48 hours of fertilization protozoans and rotifers begin to appear; after about 72 hours first food (protozoans and rotifers) becomes fairly abundant.
Use of Insecticide
PARTICULARS
Add insecticide @ 0.5–1 ppm. In case a dry pond is not available, net out the stock from the fry receiving pond as far as possible, reduce the water to minimum possible level and then apply Rotenon or any other recommended insecticide @ 1 ppm. Manure/prepare the pond as per dose referred in (ii & iii) above; add insecticide.
Add insecticide @ 0.5–1 ppm. In case a dry pond is not available, net out the stock from the fry receiving pond as far as possible, reduce the water to minimum possible level and then apply Rotenon or any other recommended insecticide @ 1 ppm. Manure/prepare the pond as per dose referred in (ii & iii) above; add insecticide.
REMARKS
Only insecticides of mild toxicity, preferably of organophosphate group, should be used. Check the toxicity of treated water after 48 hours of insecticide addition; survival of fry in water samples collected from treated pond up to 4 hours will give satisfactory results.
Only insecticides of mild toxicity, preferably of organophosphate group, should be used. Check the toxicity of treated water after 48 hours of insecticide addition; survival of fry in water samples collected from treated pond up to 4 hours will give satisfactory results.
Stocking of Fry
PARTICULARS
i) Rate of stocking – about 4,00,000 fry/acre.
ii) At the time of stocking of fry, care should be taken to ensure acclimatization of fry with pond water temperature.
iii) Start raising water level of pond by 2"–3" per day till it reaches a depth of about 3 feet after stocking.
iv) Start feeding fry with artificial feed after 10–14 days of stocking.
v) Feed ingredients may be rice polish + Maiz glutin (30% in fine powdered form) with protein ratio about 8:1 @ 5% of total weight of fry/day.
vi) Start fertilization of the pond with 1000–1500 kgs cowdung & about 8 kg inorganic fertilizer, subject to qualitative & quantitative fluctuation of plankton level.
i) Rate of stocking – about 4,00,000 fry/acre.
ii) At the time of stocking of fry, care should be taken to ensure acclimatization of fry with pond water temperature.
iii) Start raising water level of pond by 2"–3" per day till it reaches a depth of about 3 feet after stocking.
iv) Start feeding fry with artificial feed after 10–14 days of stocking.
v) Feed ingredients may be rice polish + Maiz glutin (30% in fine powdered form) with protein ratio about 8:1 @ 5% of total weight of fry/day.
vi) Start fertilization of the pond with 1000–1500 kgs cowdung & about 8 kg inorganic fertilizer, subject to qualitative & quantitative fluctuation of plankton level.
REMARKS
Proper acclimatization and gradual increase of water depth help avoid temperature shock to fry and improve survival and growth.
Proper acclimatization and gradual increase of water depth help avoid temperature shock to fry and improve survival and growth.