Title : Effects of Bacillus Licheniformis feeding on the growth performance, blood parameters, and intestinal microbiota of adult hybrid sturgeon
Abstract:
To investigate the effects of the Bacillus licheniformis addition in the diet on the growth performance, blood physical and chemical indices and intestinal microflora composition of hybrid sturgeon (Acipenser baerii ? A. schrenckii ?), 160 hybrid adult sturgeon with an average weight of 850 g were selected, and four groups were established. The fish were fed with four types of diets (equal nitrogen and fat levels) that was respectively supplemented with 0.00% (control group), 0.10% (Group B), 0.20% (Group C), and 0.40% (Group D) B. licheniformis for 120 days. Results showed that the fish in the group C had the highest final body weight, weight gain rate, and specific growth rate (p< 0.05). The feed coefficients of group B, group C and group D were significantly lower than that of control group (group A) (p < 0.05). And, the crude protein (CP) and crude fat (EE) in group B, C and D were significantly higher than that control group (p < 0.05). The serum TC and TG, ALP, ALT, AST, and GLU contents in the B. licheniformis adding groups were also significantly higher than that of control group (p < 0.05). In addition, the Cetobacterium was the dominant bacterial taxon in each group. With increasing the adding contents of B. licheniformis in diet, the Cetobacterium content decreased and the Plesiomonas content increased correspondingly. Adding B. licheniformis in diet greatly decreased the abundance of Streptococcus, Candidatus Competibacter, and Lactococcus. Our results indicated that appropriate adding (0.20%) B. licheniformis could increase growth, reduce the feed coefficient, and increase the diversity of the intestinal microbiota of hybrid sturgeon.
