Coconut Water (Cocos nucifera) as an Agent of Sex Reversal in Tilapia Larvae (Oreochromis niloticus)

Tilapia is one of the leading commodities because it has high nutritional and economic value. The growth of male tilapia is faster than that of female tilapia. The research dealt with sex reversal of tilapia using coconut water. the study is important in the field of aquaculture production since, sex reversal of tilapia to male can cause improvement on the growth of tilapia. This implicates more harvest and could aid in food security. The effort to incease the percentage of tilapia males can be done by using a maculinization with 17α- Methyltestosterone. However, this chemical material is a type of drug which can cause environmental problem and food poisoning. So, it is important to use as an natural agent on masculinization process of tilapia male which is environmetally friendly, cheaper and easy for application such as coconut water. The study aims to determaine the effect of coconut water (C. nucifera) and its optimal concentration on masculinization process of tilapia larvae. This study consider effect of coconut water on zootechnical performance of this tilapia such as survival rate, absolute weight gain and FCR. This study used compelately randomized design (CRD) with four treatments and three replications. There were four different treatments namely A (350 mL/coconut water); B (300 mL/L coconut water); C (250 mL/L coconut water and K (control treatment without coconut water immersion). Tilapia larvae were immersed in coconut water for 8 hours and then reared for 60 days at stocking density 30 fish larvae for each rearing container. The result showed that 300 mL/ L coconut water treatment increased the male sex ratio, survival rate and specific growth rate and reduced feed convertion ratio without a negative impact of survival rate of tilapia fry. In this study, the 300 mL/L cocunat water was the most optimal trreatment which produced a male sex ratio of 86.4%, survival rate of 91.1%, absolut weight gain of 61.3 grams, and feed convertion ratio of 1.17.