Finfish Breeding and Hatchery Management

Unit 3 - Breeding of major carps

3.4. Synthetic hormones for induced breeding of fishes

• Studies conducted by numerous investigators on induced breeding of fishes have indicated the superiority of several ovulating agents over fish pituitary extract.
• Although fish pituitary extract was initially used extensively for fish breeding all over the world, synthetic spawning hormones are now being increasingly used due to their efficacy and convenience.
• Banerjee et al. (1989) succeeded in the purification of pituitary gonadotropic hormone from Channa punctatus and Catla catla.
• Mammalian pituitary hormones in combination with fish pituitary gland extract precipitated spawning in fish.
• Of all the mammalian hormones tested on fish, chorionic gonadotropin (CG) has given successful result in inducing fish to breed, probably because CG behaves primarily as a luteinising hormones (LH).
• Synahorin (a mixture of CG and mammalian pituitary extract) in combination with pituitary gave positive results when injected to rohu.
• Sinha (1969) reported the fractionisation of pituitary extract from carps and tilapia. He obtained success in spawning of carps.
• Bhowmick et al. (1979) found mammalian hormones antuitrin-s, leutocyclin and RH-LH ineffective when injected singly or in combination with carp pituitary extract.
• The CIFRI, Barrackpore undertook detailed studies on the use of LH-RH alone or in combination with progesterone and obtained breeding success which ranged between 25-49% in carps and 100% in catfish.