Effect of 17 α -methyl testosterone on sex reversal and growth of Nile tilapia (Oreochromis niloticus L., 1758)

The present study aims at developing a production of monosex population of all male Nile tilapia (Oreochromis niloticus) using 17α-methyltestosterone (17α-MT). Three treatments with a control (Control, T-1, T-2, and T-3) in triplicates were set up using completely randomized design (CRD). The control group diet was devoid of 17α–MT. The remaining groups T-1, T-2, T-3 and T-4 were fed with feed containing 50, 60 and 100 mg kg-1 of 17α –MT. Three days old fry were stocked at the rate of 300 nos per tank. The fry were fed with experimental diet for 21 days. After that it was shifted to FRP tanks. The maximum mean length and body weight was observed in T-2 is 80 ± 3.87 mm and 59.5 ± 7.4 mm respectively. Gonadal histology from 3 months reared O. niloticus for sex reversal was observed that 56.7 %, 83.3 %, 93.3 % and 90 % males respectively. The highest male population of 93.3% males was produced from treated groups of (T-2) 60 mg kg-1 17 α-MT.