The effect of probiotic bacillus amyloliquefaciens on growth performance, immune organ index and immune function of weaned meat rabbits

Abstract

Bacillus has been reported to improve the production performance and immunity of chickens and pigs, so we hypothesized that Bacillus amyloliquefaciens (BA) could effectively increase the growth performance and immunological ability of weaned meat rabbits. To verify this hypothesis, this study was designed to examine the effect of BA on the growth performance, immune organ index, and immune function of meat rabbits. A total of 160 weaned New Zealand meat rabbits (35 ± 3 days) were randomly divided into 4 groups with 4 replicates per group (n = 10 per replicate, 5 males and 5 females). The rabbits of the control group were fed with a basal diet and the rabbits of treatment groups I, II and III were fed with the basal diet supplemented with 150, 300 and 450 mg/kg BA, respectively, for a total of 8 weeks. Our results showed that BA supplementation increased daily gain and reduced feed to gain ratio. Furthermore, BA supplementation significantly increased splenic and thymic indexes and the levels of immunoglobulin M (IgM), complement 3 (C3), and C4 in the treatment groups II and III (P<0.05). Therefore, BA supplementation in the diet could effectively improve the growth performance, immune organ index and immune function of weaned meat rabbits.