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1. A SEMINAR ON SEED PRODUCTION
TECHNOLOGY OF CAT FISHES
(SINGHI AND MAGUR)
Instructors – Dr. A. P. Rao
Dr. S. Khan
Dr. S. P. Singh
Dr. N. P. Tewari
Dr. L. Prasad
Topic Related Instructor – Dr. L. Prasad
Name – NARENDRA KUMAR
B. F. Sc. IVth year
I.D.NO. F-4314/08
College of Fisheries
N. D. U. A. T. Kumarganj Faizabad

2. Index
Introduction
Reproductive biology of Magur and Singhi
Hormone administration and induced breeding.
Preparation of sperm suspension
Egg collection by stripping the female
Fertilization
Hatchery technology
Breeding technology
Larval rearing
Feeding
Advanced fry rearing

3. Introduction
The asian cat fish Clarias batrachus locally known as Magur.
There are three cultivable species Clarias batrachus, C. gariepinus
C. macrocepalus.
In natural waters the fish spawn during rainy season in Assam
June –August .
C. batrachus is widely distributed in India, Ceylon, Bangaladesh,
Pakistan and Thailand etc.
The Paddy fields which are main breeding grounds of this fish.

4. Clarias batrachus
(Magur)

5. Reproductive Biology
Age at first sexual maturity
Sexualy Mature at one year age.
Sexual dimorphism
Genital papilla in male is long and pointed.
It is round or oval, button shaped the vent in the mature
female is reddish but bulging in male it is slender and whitish.
Breeding season
It breeds only once in a year from June-August.
Peak period being July.
fecundity .
Very low in the range of 1500 to 20000.

6. Breeding technology
Maintenance of brood stock
They are to be stocked in stocking tanks cement cistern.
Female with soft bulging abdomen are selected and sample of
eggs can be collected using a catheter.
Usually selected breeders are kept starved at least for one day
to injecting hormone. This will help in keeping the
alimentary canal empty at the time of stripping.
Parental care-
The female lay eggs in pits made along the margin of water
body .
Soon after yolk sac absorption fry start moving around
feeding zooplankton .

7. Hormone Administration in
induced breeding
Crude pituitary gland extract.CPGE
 A single dose of carp pituitary 30 g./kg. body weight is found
effective in inducing clarias to spawn.
 Ovaprim.
 The synthetic hormone preparation from Syndel laboratories
Canada 0.4 ml/kg. has been found very effective in this body.

8. Preparation of sperm
suspension
Collection of milt is done by grinding the testes in 0.9 percent
saline after sacrificing the mature male.
Sacrifice a male fish by decapitation and remove the testis.
Cut the testis into pieces by a fine scissor and crush it with
pestle.

9. Egg collection by stripping the
female
Stripping the female is done about 14 to 15 hours after the injection of
CPGE/Ovaprim at 27C to 30C.
Fully mature eggs look dark brown or brownish green in colour.
The stripped fish is bathed for 2to3 minutes in potassium permangnate
solution after which it is released in to stocking tank.

10. Stripping of female

11. Fertilization
The sperms fertilize the eggs.
Remove pieces of testis or any tissue from among the eggs.
The fertilized eggs are now transferred to trays for incubation.

12. Hatchery technology
Incubation –
The fertilized eggs are Demersal, adhesive and spherical.
The eggs are also treated with malachite green as a prophylactic measure
before placing the same in flow through for incubation.
Development and hatching-
The fertilized eggs undergo development and young hatches out with 25-26
hours at 27C-30C.
The newly hatched larva measures 4-5 mm. and weight 2.8to 3.2mg.
The larva usually rests at the bottom and yolk sac gets absorbed it moves in
the water and starts feeding.
Larval rearing-
The spawn can be reared in a shallow container for 10to12 days.
The larvae should be stocked at a density of 2000to4000 per square meter.
The water quality maintain to DO. 4.0ppm. To saturation water
temperature 26-31C., PH 7-8.5.

13. Feeding
Feeding has to be started on the 4th day.
Artemia nauplii is to be fed adlibitum for one week to ten days.
In addition to the artemia nauplii zooplankters like cladocerans,
moina are also preferred by Clarias fry.

14. Advanced fry rearing
10-12 days old fry can be shifted to a larger containers and
stocked 1000 fry /sq. m.
If rearing is continued in the above containars their growth is
found slowing down .
Hence the fry at this stage (20-24 days) released into nursery
tank.

15. Rearing in nursery tanks
Rearing tanks shall be of small size 50 sq.m. having sides
cemented.
The fry can be stocked 100-200/sqm. and reared for another 15
days.
Feeding can done with finely minced trash fishes or molluscan
meat and rice bran 1:1 daily in the evening hours .

16. Hetropneustes fossilis (Singhi)
Introduction
Heteropneustes fossilis is commonly known as Singhi or stinging cat
fishes which was a great potential as a candidate species for
aquaculture.
The presence of accessory respiratory organ helps thrive well in
shallow and derelict water with poor oxygen .
It also compatible with the carps in mixed culture.

17. Hetropneustes fossilis (Singhi)

18. Reproductive Biology
Age and size at first maturity-
 It attains first sexual maturity when one year old reaching 8-12 cm. length.
Sexual dimorphism –
 The male and female distinguished from each other only during breeding season.
 The female genital papilla is more prominent round.
 But male genital papilla is pointed.
Breeding season –
 It is breeds confined water during monsoon months between June and august peak
being July.
Fecundity-
 It is fecundity has been estimated at 1500-2000 eggs per gram ovary.

19. Seed production
Brood stock maintenance-
Adult brood fishes weighting 50-100g. Can be procured
from natural waters and reared in cement cisterns.
 Stocking density can be about 10-12 fish per cubic meter
Feeding can be done with molluscan meat or formulated
feed containing rice bran and fish meal.
Injection of hormones –
A female is a administered either pituitary gland extract 15-
20 mg/kg. body weight or
Salmon gonadotropin releasing hormone analoge (SGnRH-A
)500mg/kg body weight.
Ovapirm 0.6 to 0.9 ml/kg. body weight .

20. Stripping the female
The female is stripped 14 to 18 hours after hormone injection
The female wiped with the wet clothes and the readiness of the
female is tested by gently pressing the belly.
The eggs are then counted either by gravimetric or volumetric
method.

21. Preparation of sperm
suspension
The male brood fish is cut upon and testis are dissected out into a
mortar and cut into pieces in 0.6 % saline and crusted using a
pestle .
Just prior to stripping the female.

22. Fertilization
Usually the fertilized eggs are greenish blue in color and settle to
the bottom .
The unfertilized eggs are somewhat white and found floating.
The fertilized eggs are moderately adhesive.

23. Incubation of fertilized eggs
The newly hatched larvae measures 2.72 mm. in length having a
round yolk sac which forms almost 42% of the total length .
It is transparent having a laterally compressed body.
They remain at the bottom resting on their sides.

24. Rearing of fry -
Fifth day after hatching yolk sac is fully absorbed.
Tenth day it measures 7.5 mm. in length.
Care is taken to rear the spawn in shallow containers at density
of 3000 to 5000 sq.mt.

25. Feeding
The larvae stared feeding they are given adequate quantity of
live feed .
The live rotifers and ciliates 3 to 10 days .
In addition custard and mollusc an meat for the fry .

26. Preparation of egg custard
Collect the egg content (white along with yellow )and mix equal
quantity of milk powder .
Add 0.5 g vitamin, mineral piece mix and make a homogenate.

27. Rearing of advanced fry -
The transferred of old fry 10-12 day to large cement cistern or
plastic pool containing 15cm deep water .
Stocking rate can be 3000-5000 fry per sq. m.
Before releasing the water is aerated.
The fingerling can be marketed for rearing in grow out pond .

28. Reference
1. Breeding and seed production of fin fish and shell fish. P.C.
Thomas,page no.106-122
2. Handbook of Fisheries and aquaculture page no.283- S.
Ayyappan
3. www.wikkipedia.com
4. www.google.com

29. Thank You