Efficacy of 17β-estradiol on survival rate, sex reversal, and growth performance of climbing perch (Anabas testudineus) using the immersion method

This study aimed to evaluate the efficacy of estradiol on the survival rate, sex reversal ratio, and growth performance of climbing perch (Anabas testudineus) using the immersion method. A completely randomized design was applied, involving three estradiol (E2) treatment groups at concentrations of 1.0 mg/L (1E2), 1.5 mg/L (1.5E2), and 2 mg/L (2E2), along with a control group triplications. Seven-day-old fingerlings were exposed to the E2 solution for 2 h before being transferred to nurseries in hapas placed in earthen ponds at a density of 200 fish/m² for 60 days. After the hormone treatment and 60 days of rearing, the highest survival rate was observed in the control group (86.7%). The female ratios in the 17β- stradiol (E2) treatments ranged from 72.0% to 90.0%, which were significantly higher than the ratio of the control group (55.6%) (P < 0.05). The 2E2 treatment demonstrated the highest female percentage, which was statistically greater than that observed in the 1E2 and 1.5E2 treatments (P < 0.05). The mean weight and length of fish in the E2 treatments were greater than those in the control treatment, although the differences were not statistically significant (P > 0.05). Additionally, the study revealed a direct proportionality between the average weight of experimental fish and the hormone concentration. Based on these findings, the recommended dose for achieving maximum mono-sex female climbing perch is 2 mg/L of 17β-estradiol.