Temperature during early life determines sex in zebrafish, Danio rerio (Hamilton, 1822)

Abstract

It is well established that phenotypic sex in many gonochoristic fish species is the combined outcome of genetic and environmental factors, with temperature having the most profound influence of any environmental factor on sex differentiation. This study demonstrates that water temperature during early life (from spawning up until after metamorphosis) has a drastic influence on the sex ratio of zebrafish (Danio rerio), with male-biased populations produced at lower temperatures (22AEC, 87.1% males) and female-biased ones at higher temperatures (31AEC, 82.4% females). Since zebrafish is employed extensively as a model organism for a variety of research studies, these results can be of great importance to the designing of experiments where the sex of the fish is of relevance to the studied parameters.