Breeding and spawning of fishes: Role of endocrine gland

Abstract

The fish pituitary is an endocrine gland of dual origin found on the ventral side of mid brain attached to it by means of stalk. The pituitary gland produces and stores gonadotropin hormones (GtH), which play a decisive role in ovulation and spermiation. Hypophysation is a technique whereby ripe fish brooders are stimulated by pituitary hormone introduction to spawn in captive condition. Injected pituitary gland extract bypasses the brain-pituitary link, acting directly on the ovaries and testes, providing the surge in blood GtH levels that normally precede spawning. This technique has been developed for the production of good quality spawn of certain fish species in captivity by manipulating its reproduction with control timing and synchrony of egg production, while natural spawn collection yields some undesirable wild species and is not profitable for culture. This paper explains general organisation and morphology of pituitary gland and it’s the role in induce breeding of fishes.