Effect of high dietary carbohydrate on growth, serum physiological response, and hepatic heat shock protein 70 expression of wuchang bream (megalobrama amblycephala) at two temperatures

Özet

The effects of high carbohydrate diet on growth, serum physiological response, and hepatic heat shock protein 70 expression in Wuchang bream were determined at 25 °C and 30 °C. The fish were reared at 25 °C had significantly higher serum C3, respiratory burst activity and hepatic superoxide dismutase activity, lower hepatic malonaldehyde than those were reared at 30 °C (P<0.05). At each temperature, the fish fed the control diet (31% CHO) had significantly higher weight gain, specific growth rate, respiratory burst activity, lysozyme, alkaline phosphatase, hepatic total antioxidative capacity, lower feed conversion ratio, glutamic-oxaloacetic transaminase, cortisol, hepatic malonaldehyde and the relative level of hepatic HSP70 mRNA than those fed the high-carbohydrate diet (47% CHO) (P<0.05). Significant interactions between temperature and diet were found for glutamic-oxaloacetic transaminase, C3, lysozyme, alkaline phosphatase and respiratory burst activity and hepatic superoxide dismutase activity (P<0.05). The present study suggested that higher dietary carbohydrate impact growth performance, the nonspecific immune ability and hepatic antioxidant abilities of Wuchang bream at higher temperature.