A 90-days experiment was conducted on Cyprinus carpio in eight rectangular earthen ponds (21 ×10 × 1.50 m) for testing the effect of four groundwater salinities (0, 5, 10, and 15ppt). At the end of the experiment, 100% survival was observed in all of the treatment groups. Somatic growth and reproductive performance were significantly (P < 0.05) influenced by salinity.
The results showed that average weight of the matured brooders were 370 ± 20 g, 342 ± 26 g, 275 ± 15 g,
167.5 ± 17.50 g at the salinities of 0, 5, 10 and 15 ppt, respectively. Changes in serum concentration of cortisol, 17 β-Estradiol, progesterone; 17α, 20β Dihydroxyprogesterone and androgens were investigated .
Gonadal histology in male and female C. carpio was studied at different stages of gonadal maturity till ovulation or spermiation. Serum steroid analysis showed significantly high levels (p<0.05) in fish groups reared at 0 and 5 ppt compared to 10 and 15 ppt. In the present study, C. carpio was found to mature faster at 5 ppt as compared to higher salinities of 10 and 15 ppt, in inland saline water.