Abstract
One-week old swim-up fry of Nile tilapia (Oreochromis niloticus) were used for the trial. Six dietary feeds were assigned during the sex-reversal period � the standard sex-reversal diet without 17-?-methyltestosterone (MT) (C1) standard sex-reversal diet (C2) alcohol-replaced with bull urine included standard sex-reversal diet (BU) half MT-replaced with goat testis (GT) or catfish testis (CT1) all MT-replaced with catfish testis (CT2). Catfish or goat testis to fully replace the fishmeal and half of MT yielded acceptable ratio of the male population (96.6?1.0 and 94.8?0.9% respectively) comparable to that produced from the standard diet (98.4?0.5%) (P>0.05). Bull urine can replace alcohol additionally required in the sex-reversal feed making process without compromising the fish sex efficiency. These results suggested the potential of the alternative natural products bull urine catfish and goat testes over the synthetic chemical conventionally used in the feed for sex-reversal of Tilapia. ? 2024 Central Fisheries Research Inst. All rights reserved.
