2018 Volume 89 Issue 2 Pages 207-217
The experiment was conducted to investigate the effects of a probiotic (Bacillus subtilis strain BN) on body weight gain, immune responses (each group ; n = 9), meat weight, meat quality (each group ; n = 4) and intestinal microbial flora (each group ; n = 5), in broiler chickens. The test groups were followed, only Bacillus subtilis strain BN group (BN group), only antibiotic feed additives group (antibiotic feed additives group : AFA group) and either Bacillus subtilis strain BN and antibiotic feed additives group (control group). As immune responses, we examined responses to T cell-dependent and T cell-independent antigens and delayed type hypersensitivity reaction. As meat quality, we examined heating loss, shear force, meat press juice rate and moisture of breast meat. The intestinal bacterial flora was examined in 4 positions ; crop, duodenum, jejunum・ileum and cecum. As a result, the total number of anaerobic bacteria in the jejunum・ileum was significantly higher in BN group than in the AFA and control groups (P < 0.01). There was no significant difference in meat weight, meat quality and immune responses. On the other hand, the average body weight of BN group at 7 weeks of age was lower than that of the AFA group, but it was equivalent to the control group. In conclusion, BN group is inferior to the AFA group in the body weight gain. Immune responses and meat quality of BN group are equivalent to AFA and control groups.
