Effect of different levels of dietary copper nanoparticles and copper sulfate on growth performance, blood biochemical profiles, antioxidant status and immune response of red sea bream (Pagrus major)

Abstract

A 60days feeding trial was conducted to evaluate the effects of dietary copper nanoparticles (Cu-NPs) or copper sulfate (CuSO4) on growth performance, blood biochemical profiles, antioxidant status and immune response of red sea bream (Pagrus major) (initial body weight: 3.30±0.02g). Six diets were formulated containing CuSO4 or 2, 4, 6 or 8mg supplemental Cu as NPs were supplied to the basal diet (control). The obtained results showed that, fish fed diets supplemented with Cu-NPs at levels of 2 and 4mgkg−1 had the highest values of final body weight, weight gain, specific growth rate, feed intake, protein gain and tolerance against low-salinity stress. Significantly higher feed efficiency ratio, protein efficiency ratio, protein retention, whole body Cu content, protease activity, lysozyme activity and total serum protein were found at levels of 2mg Cu-NPs kg−1 diet when compared with the control group. Whole body protein of fish fed diet Cu-free diet was significantly lower than those of fish fed other diets. Fish fed diets supplemented with Cu-NPs at different levels gave the lowest values of plasma glucose. Furthermore, fish fed diets supplemented with Cu-NPs at 2 and 4mgkg−1 diet were in better conditions whereas, fish fed control diet implied comparatively higher oxidative conditions. Therefore, the data of the present study recommend adding 2mg Cu-NPs per kg diet to improve fish growth, immune response and antioxidant defense system. Statement of relevanceEfficiency of copper for red sea bream.