ABSTRACT
In vertebrates, including fish, sex is ordinarily determined by the genotype under normal circumstances. However, various environmental factors such as temperature have also been shown to influence sex determination greatly in some non-mammalian species such as reptiles, amphibians and fishes (Adkins-Regan, 1987). Pioneering experiments by Yamamoto (1969) using medaka (Oryzias latipes) demonstrated that androgens and estrogens induce complete masculinization and feminization, respectively, leading to a hypothesis that steroids are endogenous inducers, namely estrogens and androgens are the female and male inducers, respectively. Since
then, many studies have been performed in some gonochoristic fishes on the effect of steroids on gonadal sex differentiation.
