Effect of hormonal masculinization on growth performance of tilapia (Oreochromis niloticus)

Abstract

The present study was conducted in the Meridian hatchery, Sonagazi, Feni, to evaluate the effects of 17α-methyltestosterone hormone on the growth performance of Nile Tilapia Oreochromis niloticus). Brood fishes were collected from NAMSAI farm, Thailand and BFRI, Bangladesh and then stocked in the breeding hapa. A total of 1600 brood fishes were used in 10 hapas where stocking density was maintained at 5 fishes/ sq. m and sex ratio was maintained at 3:1. Eggs were collected from the fish mouth, disinfected and finally placed on the hatching trays and jars. The hatched larvae were placed in the 12 SRT tank and different doses of 17α-methyltestosterone hormone applied. The experimental treatments were T0 (Control, without MT), T1 (50 mg MT/kg), T2 (60 mg MT/kg), T3 (80 mg MT/Kg) and each treatment had three replications. The study showed significantly higher growth performance in the T2 treatment. The results showed that the mean weight of fish was significantly higher under T2 (533.5±1.249 g), mean length was under T2 (29.97±0.153 cm) and SGR was under T2 (4.259±0.0013) in comparison with the other three treatments. The highest survival rate 87.6% was obtained in T2. The highest value of FCR (1.8) was observed in T1 and the lowest (1.2) was in both T2, T3, respectively. The highest sex reverse percentage was found in T2 (98%) followed by T3 (97.883%) and T1 (77.833%). There was a strong interaction between 17α-methyltestosterone hormone and growth performance and sex reversal of Nile Tilapia (p < 0.05, n=4). This study suggests that the use of 17α-methyltestosterone hormone can improve the growth performance of Nile Tilapia.