Effects of three probiotics on growth performance, blood biochemical indexes, immune and antioxidant capacity and intestinal health of Aquarana catesbeiana

Objective This study aims to investigate the effects of dietary probiotics on growth performance, blood biochemical indices, immune and antioxidant capacity, and intestinal health in Aquarana catesbeiana.

Method The control group was fed the basal diet. Experimental diets were formulated by supplementing with Clostridium butyricum (2.92×10⁷ cfu/g), Bacillus coagulans (0.91×10⁷ cfu/g), or Saccharomyces cerevisiae (the mass fraction was 0.2%). A total of 432 A. catesbeiana with an initial body weight of (38.94±0.04) g were randomly assigned to four groups with three replicates of 36 frogs each. The feeding trial lasted for 56 days.

Result 1) Survival rate, feed conversion ratio, and protein deposition rate showed no significant differences among groups. The C. butyricum group achieved significantly higher final weight per frog, weight gain rate, and specific growth rate compared to other three groups. 2) Trypsin (TRY) activity in the liver and foregut was higher in all test groups than in the control, with the C. butyricum and S. cerevisiae groups showing significantly higher activities and the C. butyricum group being the highest. 3) The C. butyricum group showed significantly higher total cholesterol (T-CHO) concentration and significantly lower aspartate aminotransferase (AST) activity. The S. cerevisiae group had significantly elevated blood glucose (GLU) concentration. The control group exhibited significantly higher triglyceride (TG) concentration and alanine aminotransferase (ALT) activity than three test groups. 4) Compared to the control group, A. catesbeiana in the test groups had significantly higher levels of liver antioxidant indices including alkaline phosphatas (AKP), total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities and total antioxidant capacity (T-AOC), intestinal lysozyme (LZM) activity, and serum immune indices (LZM and AKP activities, T-AOC). The C. butyricum group demonstrated the best performance in liver catalase (CAT) activity, intestinal AKP activity, and most immune-antioxidant parameters, its liver malondialdehyde (MDA) content and serum T-AOC in the C. butyricum group did not differ significantly from other groups, whereas liver MDA content was significantly elevated in the control group. Additionally, liver LZM activity was significantly increased in the S. cerevisiae group compared to the control group.

Conclusion Dietary supplementation with C. butyricum, B. coagulans, or S. cerevisiae improves digestive enzyme activity, immune function and antioxidant capacity, and intestinal villus growth in A. catesbeiana, with C. butyricum showing the best overall efficacy.