Dietary nano-selenium improves health of liver and intestine of grass carp Ctenopharyngodon idella after overwintering

The purpose of this study was to examine the effects of nano-selenium (nano-Se) on the health of liver and intestine of grass carp (Ctenopharyngodon idella) after overwintering. Grass carp were fed three diets contained 0 mg/kg (control group, Se0), 0.3 mg/kg (Se0.3) and 0.6 mg/kg (Se0.6) nano-Se for 60 days before the overwintering. After overwintering, evaluation of the Se deposition, biochemical parameters, histopathology, and the expression of genes involved in inflammation, oxidative stress and tight junctions were performed. The results showed that the content of Se in the liver and intestine were significantly increased as dietary nano-Se level increased. The addition of 0.3 and 0.6 mg/kg nano-Se significantly reduced the levels of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and malondialdehyde (MDA) in the serum (P