Feminization of Channel Catfish by Oral Administration of Steroid Sex Hormones

Abstract Oral administration of 17-β-estradiol or 17-α-ethynyltestosterone to sexually undifferentiated channel catfish Ictaturus punctatus during the first 21 days after yolk-sac absorption resulted in the production of 100% females. The androgen was effective at doses of 6 to 600 μg/g of feed, but not at 0.6 μg/g. Received February 5, 1983 Accepted June 12, 1983