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This study evaluated growth, survival, and oogenesis before and after 17β-estradiol (E2) treatments. During the growth period, C. viridis reached a total length of 65 ± 4.2 cm and a weight of 2.5 ± 0.66 kg BW. To induce sex change in males, we implanted silastic tubing loaded with 0 (control), 0.5, or 1.5 mg of E2 kg−1, at days 0, 30, 60, and 90. Blood samples were collected before treatment (day 0) and on days 30, 60, 90, and 120. Initially, 23% of the selected males expressed milt. At 60 days post-treatment 13% in the control and 4.3% in both, 0.5 and 1.5 mg E2 kg−1 BW treatments. After 120 days we observed histological evidence of sex change in 50% of the histology-tagged fish in the 1.5 mg E2 kg−1 treatment. The gonadosomatic index and condition factor did not differ significantly (P > 0.05) between the control and the treatments. However, the mean individual fish weight differed significantly across all sampling times (P |
