inducded breeding in feshes

2. By: Khansa
M. Phil zoology

3. OUTLINE:
INTRODUCTION
HISTORY
TECHNIQUES
FACTORS
PROBLEMS
ADVANTAGES AND DISADVANTAGES

4. Induced breeding
 Induced breeding is a technique by which the
economically important fish (which generally do not
breed in captive condition) are bred through artificial
stimulation.
 Induced breeding is a technique whereby ripe fish
breeders are stimulated by pituitary hormone or
any other synthetic hormone introduction to breed
in captive condition.

5. WHY INDUCED
BREEDING??
Induced breeding is a technique where organism
is stimulated by particular hormone or other
synthetic hormone or by providing condition,
introduced to breed in captive condition.
The stimulation promotes timely release of
sperms and eggs from ripe gonads.

6. NEED OF INDUCED BREEDING
Because of environmental condition like
photoperiod, rain, Temperature, currents
of water.
 Insufficient release of hormones in
captive condition.
Insufficient of natural foods.

7. INDUCED BREEDING IN FISHES
The Artificial Process By Means Of Which The
Extract Of The Pituitary Is Introduced Inside
The Body Of Both The Matured Male And
Female Fishes, Then After Being Excited, They
Lay Eggs In The Pond Water And Subsequently
Fertilization Takes Place And The Process Is
Called Induced Breeding Of Fishes. This
Process Of Breeding Is Also Known As
Hypophysation.

8. HISTORY OF INDUCED BREEDING
 The technique of induced breeding was first
evolved in Argentina after producing pituitary
extract by B. A. Hussay in 1930.
Brazilian was the first country to develop a
technique for hypophysation in 1934.
 In India, first attempt to induce breeding was made
by Hamid khan in 1937 on Cirrhinus mrigala.
 Dr. Hiralal Chaudhary applied this technique in
minor carps in 1955.

9. WHY DOES FISH NOT
BREED IN CAPTIVITY??
 Many cultural farm fishes like IMC do not breed in
captivity. The reason may be.
 Environmental and consequently hormonal.
 Certain environmental parameters like photoperiods,
rain, temperature, current of water influence the
hormonal activity from pituitary and gonads.
 Disturbances arise in environment may cause the
insufficient release of hormones in captive conditions
and thus, the fish does not breed in captivity.
 Other factors like poor foods or insufficient natural
foods, exposure to biocides and other pollutants badly
affect the maturation of ovary.

10. WHY INDUCED BREEDING IS
NECESSARY FOR FISH CULTURE:
It gives pure spawn of certain species of fishes under
cultivation. Spawn collected from natural water is not
pure as because some undesirable wild species may come
with them.
In culture pond, Sorting of pure seed is quite impossible
in those stages. In later stages it is possible, but time
consuming.
It assures timely available of pure seed, where as in
nature the availability of seed is quite uncertain.
It can fulfil any quantity of demand in any time

11. Cont..…..
The technique is very simple and does not need too
much technical assistance or knowledge. It can be easily
learnt by a layman without much training.
The cost of expenditure is very low than the natural
collections of spawns.

13. TECHNIQUES
FOR INDUCED
BREEDING

14. Method of Induced Breeding
Spawning
Injection
Preservation of Extract
Preparation of Gland Extract
Removal of Gland

15. Fish Pituitary Gland—Collection and
Preservation
1-Location of pituitary gland:-
 Pituitary gland is also
known as Hypophysis.
 This gland in fishes is
located at Sella turcica of
sphenoid bone
 It is situated on the ventral
side of the brain just
behind the optic chiasma
and below the
Hypothalamus.

18. REMOVAL OF GLAND
REMOVAL THROUGH FORAMEN MAGNUM:
 The foramen magnum was first exposed by removing
vertebral parts adhering to skull. Fat is removed first by
means of forceps and then cotton piece. A pair of forceps
then inserted into foramen magnum dorsally to the brain and
anterior part of the brain now detached and remaining is
carefully lifted out through the foramen magnum. The gland
is then located and removed.

19.  material used for pituitary
extract preparation
and injection.
(A) homogenizer
(B) Head centrifuge
(c) syringe
 Different Forceps that
used in removing the
gland

20. Removal of gland by dissecting head:-
 This technique is not used commercially as because the heads
are damaged by this process.
 At first the head is dissected using sharp butcher’s knife, a
portion of scalp is chopped off in a clean cut with one stroke.
 Fat surrounding the brain is removed with the help of cotton.
 Olfactory and optic nerves are now severed, and then brain is
lifted up and removed. Locate the gland.
Dissecting the head of fish

21. Cont..…….
 The gland may come up along with
the brain or may remain behind on
the floor of brain cavity often
covered with a membrane.
 In any case the gland is carefully
removed after separating it from
membrane or the brain proper.
 The gland must not be damaged or
torn.
 The first method of removal is less
time consuming and economical as
the heads are used for human
consumptions later

23. Collecting pituitary gland

24. C). PRESERVATION OF GLAND :
I-ALCOHOL PRESERVATION: After collection of
glands immediately put in absolute alcohol for defatting
and dehydration. After 24 hour’s glands washed with
absolute alcohol and kept again in fresh abs. Alcohol store
in refrigerator up to 2-3 years or at room temperature up to
1 year.
II-ACETONE PRESERVATION: Glands kept in fresh
acetone or in dry ice-chilled acetone inside a refrigerator at
-20 0C for 36-48 hours. 2-3 changes of acetone at about 8-
12 hours intervals glands are taken out of acetone, put on
filter paper and dried at room temperature for one hour.
largely practiced in USSR and USA.

25. (D). PREPARATION OF GLAND
EXTRACT:
 Gland weighed and homogenized in distilled water or 0.3% saline
 Final volume should be 0.2ml/kg BW of the fish
 Centrifuged the suspension
 Supernatant used for injection
 Extract of the gland prepared just before injection
PRESERVATION OF GLAND EXTRACT
Preserved extract in glycerin and kept in refrigerator for 24 hours and
preserved in propylene glycol and kept in refrigerator for 30 days with
Immersed in 1.5% TCA for 12 hours and kept in refrigerator for 10 days

26. (E). BROODER SELECTION:
The brooders must be healthy enough and ripe
2 – 4 years of age is generally selected
1 – 5 kg body weight is preferable

27. Morphology and behavioral
To observe the sex of a fish, you’ll have to observe
the fish’s size, shape, appearance, and behavior
Compare the size of the fish during spawning
season. With many fish, like koi, females tend to be
larger than the males.
This is especially true during spawning time, when
females have large abdomens. .
 This is often caused by the fact that the female
carries the eggs in her abdomen.
 Once the eggs are laid during spawning season, the
females and males can return to the same size.

28. Cont.….
 Difference Between male and Female Character Look for a
bump on the forehead of the fish to identify a male.
 Look carefully at the face of the fish just between the eyes
and above the mouth.
 If it has a large, protruding bump, there’s a good chance that
the fish is a male.
 This bump is called a “nuchal hump,” and it’s present on
many types of fish, like the tilapia, angelfish, and parrot fish
etc.
 Some species of fish don’t have a nuchal hump, but the
presence of one is normally a great indicator that you have a
male fish.

31. F).INJECTION TO THE
BROODERS:
 The pituitary extract is administered into the body of breeders
by means of hypodermic syringe either intra muscular or intra
peritoneal.
 Determination of correct dosage of pituitary extract to be
given to the breeders is very important and depends upon the
size and state of maturity of the recipient (breeders) as well as
upon the state of maturity of the donor for the glands.
 Intra-cranial injections preferred in USSR and intraperitoneal
in USA and japan.
 Intra-muscular injection is most common practice in India.
 Intra-muscular injection given at the caudal peduncle or
shoulder regions near the base of the dorsal fin.
 Intra-peritoneal injections given at the base of the pelvic fin
or pectoral fin.

35. DOSAGE OF PITUITARY
EXTRACT
Female given 2 doses
1. Initial dose: 2-3mg/kg body weight.
2. Resolving dose / final dose: 6-8mg/ body
weight.
Male given only 1 dose at the time of the 2nd
dose given to female (2-3 mg/kg body weight).
For females of Indian major carps one initial
and after 5-6 hours final dose given.

36. Dose of fish Synthetic Hormone of
Ova tide
Species Female(ml/kg) Male(ml/kg)
Labeo rohita 0.20-0.40 010-0.20
Cirrhinus mrigala 0.20-0.40 0.10-0.20
Sliver carp 0.40-0.50 0.20-0.25
Grass carp 0.40-0.50 0.20-0.25
A text book of fish and fisheries – Pandey and Shukla.

37. SPAWNING
After injection to the brooders, a set of brooders
are released into breeding hapa. The hapa is the
fine netting, rectangular in shape and is held by
four bamboo poles one at each corner.
Closed meshed mosquito netting is preferred for
that purpose, as its meshes will allow a good
circulation of water and will also not let the laid
eggs and milt escape through the meshes.

38. Spawning hapas

39. Spawning pools

40. Stripping :-
In stripping method, the ‘eggs’ and ‘milt’
are forcibly extruded out by applying
pressure on the belly of breeders when
they are ready to breed.
Two methods of stripping are generally
practiced — dry method and wet method:
Dry Stripping
Dry Stripping:

41. Dry Stripping:
The dry method of stripping has been found
to be more convenient and effective and is
widely practiced in India. In this method after
3-4 hours of the second infection, the female
fishes are examined, whether they have
become fit for stripping. The female breeders
become fit for stripping when the abdomen
becomes very soft and eggs oozes out freely
on applying slight pressure on the abdomen

42. Fig: dry stripping__(a) Eggs are collected in an
enamel tray. (b) milt is exuded over the eggs

43. Wet striping:
In some countries wet method of stripping
is also practiced. In wet stripping 0.3%
saline solution is used. The salt solution is
taken in an enamel tray and the males are
made first to exude milt. Then the female
breeder is taken and the eggs are stripped
into the tray. Generally, the sperms of
Chinese carp remain active up to 2-3
minutes in 0.3% saline, while they die
much earlier in ordinary water.

44. Wet stripping:

45. FACTORS INFLUENCING THE
SPAWNING OF FISH:
 Climate - 24°C to 31°C with cloudy
days and rainy periods. Light drizzling
following heavy rains is ideal. In absence
of rain artificial showers are used.
 Water – flowing water is preferred.
 Turbidity – 100ppm 1000ppm.
 Light – it is known to bring that light
may help in early maturation and
spawning of fish.

46. PROBLEMS OF HYPOPHYSATION
TECHNIQUE
 Farmer cannot measure the potency of the
available gland
 Serious difficulties in large scale collection
and storage of pituitary
 Large gap between the supply and demand of
pituitary
 Basic equipment’s like chemical balance,
centrifuge and refrigerator normally not
available in several farms
 Pituitary gland very costly in market.

47. advantages of induced
breeding:
Desired species of carps can be cultured through
the induced breeding.
Large number of eggs are available from a fish
through induced breeding.
In same season, a carp can be breed more than
once .
Transport cost becomes very low as the caps can
breed in any desired pond.

48. References :-
Fish and Fisheries of India – V. G. Jhingran
 General and applied Ichthyology – S. K. Gupta
and P. C. Gupta
A text book of fish and fisheries – Pandey and
Shukla.