Sex Control

Abstract

The obvious aim in the husbandry of fish for food is to use the fastest growing types and to harvest them at the end of their period of fastest growth and most economic food conversion ratio (FCR). In some species of fish, notably tilapia and salmonids, there are problems relating to sexual maturation and there are economic advantages in growing single-sex populations. Tilapia have high fecundity but somatic growth can be stunted when they are kept at high stocking densities. It is virtually essential to have single-sex populations to produce fish in excess of 300 g liveweight. Although tilapia males mature at low body weights they grow significantly faster than females, and so a single-sex population should preferably be male.