Effects of Zn²⁺ and Cu²⁺ on loach ovaries and ova development

This study compared the accumulation of Zn²⁺and Cu²⁺ in the ovaries and ova of loaches under different concentrations of Zn²⁺ (1.00, 2.50 and 5.00 mg/L respectively) and Cu²⁺ (0.10, 0.25 and 0.50 mg/L respectively). The results showed that both Zn²⁺ and Cu²⁺ accumulated in the ovaries, and that the relationship between accumulation and time was linear over 20 days of exposure. The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions (P<0.05), and was obviously affected by the time and doses. However, the Cu²⁺ concentration was significantly higher than Zn²⁺(P<0.05). The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn²⁺ and Cu²⁺ solutions.