Fry production of Shire River tilapia Oreochromis shiranus at two broodstock sex ratios

Abstract

Optimal sex ratio in tilapia breeding ponds depends upon stocking density. However, under certain circumstances, altering the male: female sex ratio from a more or less natural 1:1 to 1:2 or even higher has been shown to increase fry production in oreochromiines. The research reported here was a first step toward establishing the broodfish sex ratio that Malawian smallholders ought to use to produce the maximum number of 0. shiranus fry under local conditions.