Abstract:A feeding trial was conducted to investigate the effects of dietary curcumin at different levels on the growth performance, digestive enzyme activities and antioxidant ability of yellow catfish (Pelteobagrus fulvidraco). Juvenile yellow catfish with an initial body weight of (13.17±0.68) g were fed with 6 different experimental diets containing curcumin at the concentration of 0 (control), 50, 100, 200, 400, and 800 mg/kg (namely T1, T2, T3, T4, T5 and T6 respectively) for 60 days. There were 3 replicates per group of 40 yellow catfish. The results were described as follows. The specific growth rate (SGR) and the survival rate (SR) of fish fed in the control group were significantly lower than those of all treatment groups (P<0.05), and the feed conversion ratio (FCR) was higher in T3 and T4 than the control group (P<0.05). The lipase activity in the foregut of fish from T3, T4 and T5 was significantly higher than the control group (P<0.05). The amylase activity in the foregut of fish from T4 was significantly higher than the control group (P<0.05). The level of superoxide dismutase (SOD) was higher in the hepatopancreas of fish from T6, in the brain of fish from T5 and in the head kidney of fish from T4 (P<0.05). A significantly lower content of malondialdehyde (MDA) was observed in the brain of fish from all treatment groups (P<0.05). In T5 and T6, there was a significant increase in the catalase (CAT) activity in the spleen and hepatopancreas (P<0.05). The glutathione peroxidase (GSH-PX) activity was enhanced (P<0.05) in the fish from T4, in the spleen of fish from T5 and in the mid-kidney of fish from T5, furthermore, it was also higher in the serum of fish from all treatment groups compared to the control group (P<0.05). The GSH activity in the hepatopancreas of fish from all treatment groups was higher than that in the control group (P<0.05). A significantly higher level of nitric oxide was found in the hepatopancreas of fish from T5 and in the spleen and serum of fish from T4, compared to all other treatment groups (P<0.05). The results indicated that 200 mg/kg curcumin supplemented into the diets could effectively boost the growth performance, and enhance the intestinal digestive enzyme activities and the antioxidant ability of juvenile yellow catfish.
