Effects of replacement of dietary fish oil by rapeseed oil on growth performance, anti-oxidative capacity and inflammatory response in large yellow croaker Larimichthys crocea

A 12-week feeding trial was conducted to evaluate the effects of replacement of dietary fish oil by rapeseed oil on the growth, anti-oxidative capacity and inflammatory responses of large yellow croaker Larimichthys crocea (initial body weight 36.02 +/- 0.58 g). The control diet was designed to contain 6.5% of fish oil, and named as FO. Based on it, the fish oil was 50% and 100% replaced by rapeseed oil to make the other two diets (FR and RO, respectively). Results showed that the specific growth rate was significantly reduced, and the crude lipid contents in muscle and liver were significantly increased in the RO group. The total anti-oxidative capacity and expressions of superoxide dismutase 1 and 2, glutathion peroxidase and nuclear factor erythroid 2-related factor 2 in liver of fish fed RO were significantly lower. Dietary rapeseed oil significantly decreased expressions of arginase I and interleukin 10, and increased expressions of TNF alpha, interleukin 1 beta, toll-like receptor 22 and myeloid differentiation factor 88 in liver. In conclusion, high dietary rapeseed oil could suppress growth performance and liver anti-oxidative capacity, and induce inflammation of large yellow croaker.