Assessment of common carp testis as an alternative to 17α Methyltestosterone for sex reversal of Nile Tilapia (Oreochromisniloticus)

Abstract The sex reversion technique in fish is widespread in many countries. The present study aimed to produce a monosex populations of all male Nile tilapia (Oreochromis spp.) using 17α-methyltestosterone (17α-MT) and common carp testes (as a source of natural androgen). The experiment was divided into two consecutive phases, the first was fry administration with negative control (without hormone) and positive control (with hormone)feed viz.,MT1:60mg/kg, MT2:70mg/kg (17α-MT),carp testis CT1:70% and CT2:80%for 30 days to reverse the sex of male fish and second phase was nursing the fingerlings for two months on control diet (32%CP).Two hundred fry of 4–5 days old were randomly stocked in five aquariums each with one replicate (20fry/aquarium)using completely randomized design (CRD). Results revealed a significant growth rate (P < 0.05) in control group. In case of proximal chemical composition of body meat, CT2 treatment showed maximum deposition of crude protein, crude fat, and ash whereas dry matter showed maximum in MT2 and CT1 treatments. The highest male proportion (95% ± 0.58%) was recorded at 70mg/kg MT, which was significantly higher (P < 0.05) than other groups.These results suggested that synthetic and natural androgen supplementation in the diet play a significant role in improving the growth performance and body composition. Furthermore, synthetic androgen compared to natural androgens played a significant role to induce sex inversion.