Effects of Bacillus subtilis on growth performance and intestinal digestive function of yellow broilers

The aim of this study was to investigate the effects of Bacillus subtilis 0048 (BS0048) on the growth performance and digestive function of the intestinal tract in yellow broilers. A total of 980 male Xueshan chickens with similar weight (61.5 g +/- 0.5 g) were randomly divided into control (basal diet) or treatment groups (basal diet supplemented with 0.1% (W/W) BS0048), with 7 replicates per group and 70 chickens per replicate. The chickens were raised for 80 days to observe the effects of BS0048 on their growth performance, viscosity and pH value of intestinal chyme, duodenal digestive enzyme activities and caecal volatile fatty acid (VFA) contents. The results showed that compared to the control group, average daily gain, duodenal digestive enzyme activities and caecal VFA contents in the treatment group were significantly increased (P<0.05), whereas viscosity of intestinal chyme was decreased (P<0.05) on day 40 and remarkably decreased (P<0.01) on day 80. Feed conversion ratio and pH value of intestinal chyme had no significant changes. It is concluded that the use of BS0048 could not only reduce viscosity of intestinal chyme and enhance the duodenal digestive enzyme activities to enhance intestinal digestive function, but also could promote the production of caecal VFAs to maintain and improve intestinal health and thus enhance the growth performance of Xueshan chickens.