DietaryandSupplementation Modulates Intestinal Immunity and Microbiota of Broiler Chickens Challenged by.

Abstract

Preventative effects ofandagainstinfection in broilers have been well-demonstrated. The present study was conducted to investigate the modulation of these two probiotics on intestinal immunity and microbiota of-challenged birds. The 336 one-day-old broilers were assigned to four groups with six replicates in each group. Birds in the control were unchallenged and fed a basal diet, and birds in the three challenged groups were dietary supplemented with nothing (Cp group), 1 &#xd7; 10CFU/kg of(Lf_Cp group), or 1 &#xd7; 10CFU/kg of(Bc_Cp group). Challenge was performed from days 14 to 20, and samples were collected on days 21 and 28. Challenge upregulated interleukin (IL)-1&#x3b2; and transforming growth factor (TGF)-&#x3b2;4 mRNA expression in jejunum on day 21, which was downregulated byand, respectively (< 0.05). Both probiotic groups upregulated jejunal IL-1&#x3b2;, interferon (IFN)-&#x3b3;, IL-17, and TGF-&#x3b2;4 on day 28 as well as IFN-&#x3b3; on day 21 (< 0.05). The Bc_Cp group increased CD3T cell counts in the jejunal crypt on day 21 (< 0.05). Challenge decreased the ileal ACE index on day 21 and cecal microbial richness on day 28, which were increased by probiotic treatments, and ileal bacterial richness decreased in the Bc_Cp group on day 28 (< 0.05). Only ileal microbiota on day 21 was distinctly affected with an R-value at 0.3116 by ANOSIM analysis (< 0.05). Compared with the control, ilealincreased on day 21, and ilealand cecaldecreased on day 28 in challenged groups (< 0.05). Challenge increasedspp. in the ileum as well as unclassified f_andgroup in the cecum, and decreasedspp. in the ileum on day 21, which were all conversely modulated by(< 0.05). Challenge increased amino acid metabolism of ileal microbiota and membrane transport of cecal microbiota, and decreased amino acid metabolism of cecal microbiota on day 21, which were conversely regulated by both probiotics (< 0.05). In conclusion,andattenuated the intestinal inflammation and microbial dysbiosis soon afterchallenge.