IMPROVEMENT RATIO OF MALE TILAPIA USING 17α-METHYLTESTOSTERONE THROUGH FEEDING
The success of masculinization in tilapia shows that the use of the hormone 17α-methyltestosterone (MT) is more effective than temperature. However, the use of hormones by feeding through food has not shown better results compared to soaking the larvae. Even though the application through feeding is easier to do. Therefore, in this study, the administration of hormones through feed will be carried out with the experimental time of feeding exceeding the highest critical time, which is for 30 and 50 days. D'Cotta et al. (2007) and Ijiri et al. (2008) states that the critical time for sex change in tilapia is 9-15 days after fertilization/day post-fertilization/dpf. The objective to be achieved in this study is to obtain the optimal duration of 17α Metiltestosterone hormones through a feed to produce male tilapia mono sex. Treatment using 17α-methyltestosterone at a dose of 60 mg/kg with a treatment duration of feeding 0, 30, and 50 days. The influence of the length of time for feeding containing hormones was tested using the ANOVA test at 95% confidence intervals. The results obtained showed that the use of 17α-methyltestosterone in reversal sex with a dose of 60 mg/kg of feed with a duration of 0, 30, and 50 days showed a difference in the number of male tilapia produced. However, there was no noticeable difference in the male sex ratio at 30 and 50 days of feeding. So it can be concluded that feeding 17α-methyltestosterone hormone through the feed for 30-50 days after hatching can increase the male sex ratio in tilapia by more than 80%.