A Review on the Reproductive Dysfunction in Farmed Finfish

Abstract

Globally, fish production in the wild is decreasing, and different aquaculture systems are presently being used for broodstock development in the captivity. Seasonally, broodstock raised in captivity exhibit different form of reproductive dysfunction at the level of the brain-pituitary-gonad (BPG) axis. Primarily, vitellogenic completion and final oocyte maturation are inhibited in females, and males fail to spermiate spontaneously in the captivity. Reproductive dysfunctions are also observed during sexual differentiation, pubertal onset and sex conversion periods in teleosts. To overcome these problems, different hormonal preparations, primarily gonadotropin-releasing hormones (GnRH) are used. In recent years, kisspeptins have been shown to be potent in inducing gonadal growth and maturation in teleost fish. Understanding the form of reproductive dysfunction is important in formulating suitable hormonal preparations for inducing gametogenesis. The paper reviews the problem of reproductive dysfunction and their possible reason for formulating different hormonal preparations.