Yeast cell-wall polysaccharides improve immunity and attenuate inflammatory response via modulating gut microbiota in LPS-challenged laying hens.

peer reviewed ; Effects of dietary supplementation of yeast cell-wall polysaccharides (YCWP) on production performance, ileal microbial composition, immunomodulatory and anti-inflammatory effects in LPS-challenged laying hens, were evaluated. A total of 288 35-week-old Hy-Line Brown layers were randomly assigned into 4 dietary treatments: 0, 250, 500 and 1000 mg/kg YCWP, respectively. After a 12-week feeding period, a total of 32 birds were selected from the control (n = 16) and 1000 mg/kg YCWP group (n = 16). For each group, half (n = 8) received Escherichia coli LPS and half (n = 8) received PBS at 1 mg/kg body weight, intravenously. Results showed that YCWP enhanced feed efficiency and egg production linearly, with optimal laying performance notable in the 1000 mg/kg YCWP group. Dietary YCWP enhanced serum IgM and expression of ileal avian β-defensin, alleviated the LPS-induced elevated levels of serum IL-6 and IL-1β and the up-regulated expression of IL-1β, TNF-α, IFN-γ, and IL-6 in spleen and/or ileal mucosa. Furthermore, anti-inflammatory and immunomodulatory effects of YCWP were linked with its enhancement effect on microbial diversity, proliferation of Bifidobacteriaceae, Lactocillus, Candidatus_Arthromitus, Streptomyces, Bacillaceae, and Desulfovibrio, and reduced abundance of Shigella. Therefore, YCWP has the potentials to be utilized as safe prebiotics and gut enhancer in laying hens.