Dietary fructooligosaccharide and Bacillus licheniformis on growth performance, digestive enzyme, immune indices, and antioxidant capacity of common carp (Cyprinus carpio)

Abstract

A feeding trial of eight weeks was conducted to investigate the effects of dietary fructooligosaccharide (FOS), Bacillus licheniformis (B. licheniformis) and synbiotic in common carp (Cyprinus carpio). 360 fish averaging 12.5 ± 0.5 g (mean ± SD) were randomly divided into four groups in triplicate. D1 was the control group, feeding the basal diet. Diet 2, 3, 4 (D2, D3, D4) were test groups, adding 0.3% FOS, 1 × 107cfu/g B.licheniformis, and 0.3% FOS with 1 × 107cfu/g B.licheniformis to the basal diets (33.16% crude protein, 6.52% crude lipid and 4.93% ash), respectively. The results showed that the growth parameters such as weight gain, specific growth rate and protein efficiency rate were significantly higher in D4 group compared with the control group. The Feed conversion ratio in D2 and D4 groups had lower values compared to the control group. The intestinal digestive enzymes including protease and lipase were significantly higher in D4 group than that of the control group. On the other hand, aspartate aminotransferase and alanine aminotransferase activities, triglyceride and cholesterol content in the D4 group were significantly decreased compared with D1 group. Furthermore, lysozyme, acid phosphatase activities, and plasma complements (C3 and C4) levels in fish fed D3 and D4 diets were significantly higher than the control group. Additionally, the antioxidant status was improved, that coincided with an increase in superoxide dismutase and catalase activities, Total antioxidative capacity as well as a decrease in malondialdehyde levels in plasma. Overall, these results indicated that dietary supplementation of either individually or in combination (synbiotic) could improve growth, the immune indices, and antioxidant function of Cyprinus carpio. The combinational group showed the better result.