Effects of taurine on growth performance, digestive enzymes, antioxidant capacity and immune indices of Lateolabrax maculatus

Lateolabrax maculatus with initial body mass of (7.2±0.07) g had been fed for 56 d with five diets containing 0 (N0), 0.4% (N1), 0.8% (N2), 1.2% (N3) and 1.6% (N4) taurine, so as to investigate the effects of taurine on the growth performance, digestive enzymes, antioxidant capacity and immune indices of L. maculatus. The results show that the dietary taurine improved the weight gain rate (WGR), specific growth rate (SGR) and feed rate (FR) of L. maculates significantly (P<0.05) , especially for N2, N3 and N4 groups. The whole-body crude protein content increased but lipid content decreased with the increase of dietary taurine level (P<0.05). The activities of protease and lipase in taurine supplemented groups were significantly higher than those in the control (P<0.05). The levels of red blood cell (RBC) and white blood cell (WBC) were significantly higher in taurine supplemented groups than those in the control (P<0.05), and hemoglobin (Hb) levels in N2, N3 and N4 were higher than that in the control (P<0.05). The total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities in taurine supplemented groups were significantly higher than those in the control (P<0.05). The malondialdehyde (MDA) contents in taurine supplemented groups were significantly lower than those in the control (P<0.05). The linear regression analysis on the weight gain rate indicates that the optimal dietary taurine level for growth of L. maculates is 0.85%.