PRODUCTIVE PERFORMANCE AND SEXUAL REVERSION IN TILAPIA BY TWO HORMONAL METHODS

Abstract

The present study aimed to compare two methods of sex reversal tilapia-de-nile. The fish were subjected to treatments, BI - bath of immersion (6 mg methyltestosterone.L-¹), 36 hours each, at 6 and 10 days after the beginning of the experiment; RH - diet containing hormone (60 mg.kg^-1, for 30 days); RS - control (diet without hormone).  Each treatment contained five replicates. The parameters were: body length, weight and weight gain at 30 and 90 days; survival and masculinization at 90 days. The survival did not differ significatively among treatments, but  the percentage of masculinization in treatments BI and RH. At 90 days, RH fry presented the higher length (79.29 mm; P < 0.05%), while BI fry showed the highest weight (8.69 g; P < 0.05%). There were significant differences in length, with the RH treatment, with values (79.29 mm) at 90 days. In terms of weight, the BI treatment, showed a higher wight at 90 days (8.69g). For the sex reversal of tilapia can be used to feed with the hormone or bath, even without significant difference in hormone containing diet showed rates of masculinization higher.