Effects of Diazinon on 17β-estradiol, Plasma Vitellogenin and Liver and Gonad Tissues of Common Carp (Cyprinus carpio, L., 1758)

Both sexes of Common carp (Cyprinus carpio) exposed to sublethal concentrations (0.488 mg/L and 0.976 mg/L) of the widely used insecticide diazinon for a period of 7, 15, 30 days and effects on plasma 17 beta-estradiol (E2), vitellogenin (VTG), gonad and liver tissues were examined. In male carps, 0.488 mg/L and 0.976 mg/L diazinon elevated E2 levels following on the 7, 15 and 30 days. Both concentrations of diazinon elevated VTG levels after 15 days in males. In female carps, 0.976 mg/L diazinon elevated E2 levels after 30 days. However, 0.488 mg/L and 0.976 mg/L diazinon reduced VTG levels in female carps, at the end of experiment. Histopathological examination of liver showed dilatation of the bile ducts and sinusoids, congestion, lymphocytic infiltration, pigment accumulation and necrosis in both sexes and concentrations. Degeneration, congestion and fibrosis were observed in testis. Adhesions between oocytes and necrosis in ovary were also observed. The results showed that diazinon can affect the male and female individuals differently and has an endocrine disrupting potential.