Oxidative stress and non-specific immune responses in juvenile black sea bream, Acanthopagrus schlegelii, exposed to waterborne zinc

Juvenile black sea bream, Acanthopagrus schlegelii, were exposed to waterborne zinc (Zn) at concentrations of 0, 200, and 400 μg/L, at temperatures of 18 or 26 °C for 4 weeks. Superoxide dismutase (SOD) activities in the liver and gill of A. schlegelii significantly increased following exposure to waterborne Zn. Significant reduction in glutathione S-transferase (GST) activity in the liver and gill was observed following exposure to waterborne Zn. Glutathione (GSH) concentrations in the liver and gill also significantly decreased following exposure to waterborne Zn. Phagocytosis and lysozyme in the plasma and kidney were significantly increased following exposure to waterborne Zn. High water temperature increased alterations in the antioxidant and immune responses. The results of the present study suggest that waterborne Zn induced significant alterations in oxidative stress, increased immune responses and high temperature that trigger Zn toxicity. Keyword: Acanthopagrus schlegelii, Sea bream, Zinc, Oxidative stress, Non-specific immune response