Abstract: This experiment was conducted to study the effects of adding Bacillus megaterium to plant protein meal on tissue antioxidant capacity and serum biochemical indices of juvenile hybrid sturgeon. The fish in the 3 experimental groups were fed plant protein meal(group PM) with 105 cfu/g(group Ⅰ), 106 cfu/g(group Ⅱ) and 107 cfu/g Bacillus megaterium (group Ⅲ), respectively, taking the fish meal(group FM) and group PM as control groups. A total of 625 juvenile hybrid sturgeon with an initial body weight of(12.87±0.65) g were randomly divided into 5 groups with 5 replicates and 25 fish per replicate. The results showed that the total protein(TP) content and globulin(GLB) content were higher in serum in the experimental groups compared with the group PM(P<0.05), the content of urea nitrogen(BUN) and the content of uric acid(UA) were lower compared with the group PM(P<0.05), and which had no significant difference with the group FM(P>0.05). The activity of total antioxidant activity(T-AOC) and superoxide dismutase(SOD), the content of glutathione(GSH) were higher in tissue in the experimental groups compared with that of the group PM(P<0.05), the activity of Xanthine Oxidase(XOD) were lower compared with that of the group PM(P<0.05). In conclusion, the addition supplemental level of Bacillus megaterium to plant protein meal can improve the tissue antioxidant capacity, the protein utilization and immunity.

Key words: hybrid sturgeon, Bacillus megaterium, serum biochemical indices, antioxidant capacity