ANDROGENS IN TELEOST FISHES

Similarly to other vertebrates, the androgen testosterone (T) is prese nt in teleost fishes. In addition, 11-oxygenated androgens, especially 11-ketotestosterone (11KT) are present. 11KT is found in higher level s in the plasma of males than in females, whereas this is usually not the case for T. 11-Oxygenated androgens are generally more effective t han T in stimulating secondary sexual characters, reproductive behavio ur and spermatogenesis. Nevertheless, receptor-like binding has only r eported for T and not for 11KT.