[Inhibitory effects of tamoxifen on the normal differentiation of the female gonads of the quail embryo].

Early treatment of Quail eggs by tamoxifen produces a striking inhibition on normal differentiation of the female gonads. This anti-estrogen restricts cortical proliferation in the ovary while it favours the development of the medulla of both gonads. As a result their morphology and organization diverge toward a more neutral or even testicular pattern. Since tamoxifen is able to compete with the endogenous estrogens, these results underline their role in female differentiation of the Quail gonads.