Synergy of Astragalus polysaccharides and probiotics (Lactobacillus and Bacillus cereus) on immunity and intestinal microbiota in chicks

摘要

Probiotics and Astragalus polysaccharides (APS) can modulate systemic immunity and intestinal microbiota in animals and human beings. It is still unknown if the combined application of probiotics and APS in feed has synergistic effects on immunity and intestinal microbiota. To address this issue, this study was designed to investigate the synergistic effects on immunity and intestinal microbiota in chicks. A total of 240 female Hy-Line chicks were assigned to 4 treatments. Four treatments were fed the same corn-soy meal control diet; however, treatments 2, 3, and 4 were supplemented (per kg of feed) with 220 mg of APS, 4 x 10(10) cfu probiotics, and dual treatment, respectively. Parameters evaluated included serum Newcastle disease antibody titer, peripheral blood acid alpha-naphthyl acetate esterase-positive (ANAE(+)) T-lymphocyte percentage, immune organ relative weights and histological changes, and selected intestinal tract bacteria. Compared with the control, Newcastle disease antibody titer, ANAE(+) T-lymphocyte percentage, immune organ relative weights, histological changes, as well as lactobacilli and Bacillus cereus numbers significantly increased (P