Laetiporus sulphureus–fermented wheat bran enhanced the broiler growth performance by improving the intestinal microflora and inflammation status

This study investigates the effects of Laetiporus sulphureus–fermented wheat bran (LS) as a feed supplementation on the immunomodulative properties in broiler chickens. Crude phenolic compounds, crude polysaccharides, crude triterpenoids, and ergosterol were determined in LS water extracts. In animal experiments, 400 male broilers (Ross 308) were randomly assigned into 5 groups fed with a corn–soybean–based diet (control) and a control diet replaced with 5% wheat bran (WB), 10% WB, 5% LS, and 10% LS, respectively. Each group had 4 replicates and 20 birds per pen (total of 80 birds/treatment). The results showed that the 5% LS–supplemented group had significantly higher BW in the finisher phase (22–35 D). Better feed conversion ratio (P < 0.05) of LS-supplemented groups was observed in both the finisher phase and the overall experimental period. The LS-supplemented groups had significantly lower coliform counts in the ileum than the other treatment and control groups (P < 0.05). The results of serum immunoglobulin showed that LS supplementation significantly increased serum IgA concentration compared with the control and WB-supplemented groups (P < 0.05). Simultaneously, ileal IgA contents of the LS groups were significantly higher than in the WB and control groups (P < 0.05). Regarding proinflammatory cytokines, serum tumor necrosis factor alpha and IL-6 in the LS-supplemented groups were significantly lower than those in the 10% WB group (P < 0.05), whereas serum tumor necrosis factor alpha and IL-1β in the 5% LS group were significantly lower than in both the control and WB-supplemented groups (P < 0.05). An investigation on the effects of LS on immune-related genes in broiler showed that chickens supplemented with 5% LS had lower levels of liver and jejunum IL-1β and NF-κB mRNA compared with the control group and WB groups (P < 0.05). In conclusion, LS supplementation can potentially enhance growth performance of broilers by improving intestinal microflora and inflammation status.