Dr. SONAWANE D. L.

Associate Professor Dept. of Zoology,

Dr. Babasaheb Ambedkar Marathwada University, Aurangabad -431004. (M.S.)

ObjectivesTo understand the wider implications of Chinese

circular fish hatchery to provide quality fish seed to fish culturists of the State and Nation.

To understand the currently adopted methodologies of brood stock management, selection for spawning, nursing, rearing etc.

To highlight the embryological development of major carps.

Encourage more economically visible small– scale hatchery facilities as a resource to poor / marginal farmers.

Breeding and culture of economically important indigenous fish should be encouraged.

To aware the fish breeding centers about the results of different hormones.

Fish seed producers, hatchery operators should be trained with appropriate technologies concerning selective breeding, brood stock management, hatchery management, nursery management etc.

Initiate participatory research with farmer’s, hatchery operators on induced, selective breeding etc. the Government, Financial Institutes should help in establishing field laboratories for the said purpose.

INTRODUCTION Fish plays an important role in the life of human civilization, history

tells us that some form of fish culture existed around 300 B.C. Bengal, Bihar and Orissa are credited with age old practices in this trade.

Indian Major Carps Catla, (Catla catla) Rohu, (Labeo rohita) and mrigal (Cirrhinus mrigala) and two exotic Chinese carps, silver carp (Hypophthalmichthys molitrix) and grass carp (Ctenophryngodon idella) mature in confined water but fails to breed spontaneously in confinement. They are known to breed spontaneously during South – West rivers in monsoon.

The first attempt to breed major carps in confined water by bundh breeding technique. The use of pituitary hormone in carp breeding in India was established in 1957. It was on 10th July 1957, Cirrlinus reba, a medium carp induced to breed by administration of aqeous carp Pituitary Extract at Angut, Orissa by scientists of Pond Culture Sub-Station of Central Inland Fisheries Research Institute, Barrackpore, West Bengal,

Within the next forth night all three Indian major carps were induced breed successfully. The technique was further refined in subsequent years and has been widely practiced all over the country at farmers level

Besides Pituitary Extracts in recent years several other formulations of hypothalamic peptide hormones are also used effectively for induced breeding of carps, which are commercially available in trade names Ovaprim (manufactured by Syndel Laboratory Canada and marketed by galaxo India Ltd”) Ovatide (Hemmo Pharma Mumbai, India) and Wova – Fh (Workhardt Mumbai, India)

In Fish reproduction involves three basic steps.

Maturation :- the development of the gametes (eggs and sperms) to a point where fertilization can occur.

Ovulation :- The release of eggs from the ovary.

Spawning:- The deposition of eggs and sperms so that they can unite.

The basic principle behind induced spawning comes from the biological mechanism of natural propagation because the external ecological conditions in ponds cannot satisfy the reproductive requirements of the brood fish which are injected with extraneous hormones.

Major carps and culturable species of fish generally breed in running water in river, during monsoon when several environmental conditions are favorable for spawning.

These fish species becomes sexually mature in ponds but do not spawn, however, the brooders can be induced to spawn by administering pituitary hormones which stimulate the fish to release eggs and sperms.

This technique is based on the fact that the gonadotropic hormones (FSH and LH) secreted by the pituitary gland play important role in maturation and spawning of fishes is called “Hypophysation “.

The Brazilians were the first to develop this technique in 1930, followed by Russians who successfully applied this method to breed sturgeons. This method is now popular in Europe, America and Asia.

In India, Khana (1938) successfully induced Cirrhinus mrigala to spawn by injecting mammalian pituitary hormone.

Carp culture in India is believed to be old as Carp culture in china. Although in early years carp culture was restricted to the North eastern States of India during the last 4-5 decades it has spread to almost all parts.

Indian major carps, Catla, Rohu and Mrigal are generally stocked together. The Indian Major carps can be cultured in the ratio Catla 30%, Rohu 40% and Mrigal 30%.

Catla is a surface feeder feeding mainly on the zooplanktons. Labeo is a column feeder consuming decaying plants and detritus. Mrigala is a bottom feeder using decaying plants and detritus.

MATERIALS AND METHODS

Indian major carps i.e., Catla, Rohu and Mrigal are famous and precious fresh water fish with high nutritive and economic value. Ovaprim is used to induce final maturation, spawning and the effectiveness is to be compared with Ovatide and Pituitary Extract.

The spawning inducing of major carps with pituitary extract need lot of labour and time because the injections for female is usually twice or even there times.

Out of 2 injections, the first one is for promoting maturation and second one is for inducing spawning. Interval between 2 injections is about 6-10 hrs.

The males are given only one injection. Adult major carps of 2-5 years age are selected for every trial in the ratio of 30:40:30.

A single injection of Ovaprim and Ovatide is most often sufficient to induce spawning. It can save man power and expense.

The maintenance of healthy brood in brood stock ponds is the prime requisite for successful breeding operation, which include stocking of adult fish at the rate of 1500 kg /ha, provision of formulated diet at the rate of 1-2% of the body weight daily and water replenishment at fish breeding centre at Jayakwadi, paithan Dist. Aurangabad in Maharashtra.

We have practiced intra-muscular injections in our trails during July- August 2004 to July- August 2006. Dose of the pituitary extract depends on species, brood quality and breeding environment. A dose of 3-6 ml/kg is administrated to the female followed by a second dose 8-12 ml/kg after 6hrs males receives 3-6 ml/kg once at the time of second injection to female. Brood generally Ovulates within 4-6 hrs of the second dose.

The dose of such hormonal preparations (Ovaprim / Ovatide / Wova – FH) in general ranges 0.3-0.5 ml/kg body weight of female and 0.2-0.3 ml/kg body weight of males in all three Indian major carps.

The spawn are kept in the hatching pool till 72 hours before transfer to nursery. At present a large numbers of commercial eco-carp hatcheries and Chinese hatcheries are operating to produce the carp seed for culture in India. Intensification of carp seed production is not limited with the application of hatchery infrastructure. Now technology is available to breed the same fish 2-3 times in the season thereby resulting in 2-3 folds more production of them in the single breeding.

In the present study the doses of Ovaprim, Ovatide and Pituitary Extract were given to major carps i.e. Catla- Catla, Labeo rohita and Chierhinus mrigala for two successive years July – August 2004 to July-August 2006 and data was tabulated.

Table No.1

Dosage of different hormones induced in Indian Major Carps

Name

Pituitary Extract(ml/kg)

Ovatide(ml/kg)

Ovaprim(ml/kg)

Male Female Male Female Male Female

Catla catla(Catla)

0.30-0.600.20-0.40 [I]0.40-0.80 [II]

0.20-0.30 0.40-0.50 0.10-0.20 0.40-0.50

Labeo rohita(Rohu)

0.30-0.600.20-0.400.40-0.80

0.10-0.20 0.20-0.40 0.10-0.20 0.30-0.40

Cirrhinus Mrigala(Mrigal)

0.30-0.600.20-0.400.40-0.80

0.10-0.20 0.20-0.40 0.10-0.20 0.25-0.30

Table No.2.

Number of eggs laid by Indian Major Carps

Fishes Pituitary Extract Ovatide Ovaprim

Catla 75,000 80,000 1,00,000

Labeo 1,50,000 175,000 2,50,000

Mrigala 80,000 1,00,000 1,50,000

Table no.3.Development of hatchlings of Indian Major Carps

Developmental stages Catla Rohu Mrigal

Hatchling 4.6 mm 3.78 mm 4.2 mm

5th day 9.0 mm 8.5 mm 9.0 mm

15th day 23.00mm 23.00 mm 23.00 mm

Fry 25.00 mm 25.00 mm 25.00 mm

Semi Fingerling 26--50 mm 26—50mm 26—50mm

Fingerling 51—151 mm 51—151mm 51-151 mm

Table No.4.

Production of spawns (Lac) using different Hormones

Year

Pituitary Extract Ovatide Ovaprim

Spawn Seed Spawn Seed Spawn Seed

July – August

2004110.10 27.15 150.10 33.12 192.50 42.12

July – August

2005130.20 30.20 180.20 37.20 245.00 57.65

July – August

200690.10 22.50 130.30 30.15 178.50 44.48

CONCLUSIONS

Reproduction in fishes is regulated by both

internal mechanisms within the fish and external

environmental factors. The environmental factors trigger

the internal mechanisms into action, the internal

mechanism that control the process of reproduction in

fish is the brain—hypothalamus—pituitary—gonad

chain. Hormone—induced spawning techniques

influence this sequential mechanism at several levels,

by either promoting or inhibiting the process. The

primary substances used for hormone—induced

spawning are pituitary extract, Ovatide and Ovaprim etc

to stimulate pituitary.

@ Based on three years trial with Ovaprim, Ovatide and Pituitary extract, ovaprim has the following advantages over Ovatide and Pituitary Extract applications.

@ Percentage of fertilization and hatching are higher with Ovaprim than ovatide and pituitary extract.

@ There is no adverse effect on the health and growth of hatchlings.

@ Additional studies might provide valuable information on the growth of hatchlings.

@ Ovaprim is economically profitable as compared with others.

@ Additional experiments are essential to confirm the impact of Ovaprim on the growth and survival of brooders.

@ These observations are preliminary to draw any conclusion on growth and survival aspects of brooder.