title: Intestinal microbiota diversity and expression of pattern recognition receptors in newly weaned piglets.
abstract: This study evaluated the gastrointestinal microbial diversity and the expression of pattern recognition receptors (PRRs) of the small intestine during the first week post-weaning in newly weaned piglets. Sixteen piglets were sacrificed on days 0, 1, 4, and 7 post-weaning. Luminal contents from the stomach, ileum, and colon were collected to determine the microbiota diversity; intestinal mucosa from the ileum was collected to assess mRNA expression of PRRs, including toll-like receptors (TLRs) and NOD-like receptors (NLRs); sections of ileum were examined immunohistochemically to assess the immunoglobulin-secreting cells. The results showed that the number of denaturing gradient gel electrophoresis (DGGE) bands from the ileum and colon contents were significantly reduced in the d 4 post-weaning group. Biodiversity indexes (Shannon-Wiener index, richness index, and evenness index) were significantly decreased in the ileum of weaning groups. These indexes decreased in the colon of the d 4 post-weaning group. No significant differences were obtained in the stomach. With the exception of TLR5, the mRNA expressions of TLR2, TLR4, and TLR7 increased post-weaning. The mRNA expressions of NOD1 and NOD2 were significantly affected in the d 4 post-weaning group, and there were no significant differences in the d 1 or d 7 post-weaning groups. Analysis of the immunoglobulin-secreting (IgA, IgG, and IgM) cells showed that the ratio of each immunoglobulin was significantly higher on d 7 than d 0. The results revealed that microbial diversity was lower in the ileum and on d 4 post-weaning. Weaning significantly affected the expression of intestinal PRRs mainly on d 1 and d 4 post-weaning. The expression of specific PRRs was triggered by weaning to recognize distinctive microbiota and promote the development and maturation of the intestinal mucosal immunity.
authors.affiliation: Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Tao
authors.affiliation: Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, PR China. Electronic address: xzwfyz@sina.com.
authors.forename: Ziwei
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wan
mesh_terms: D000818:Animals; D000917:Antibody Formation; D044822:Biodiversity; D000069196:Gastrointestinal Microbiome / Q000235:genetics*; D015870:Gene Expression; D018928:Immunity, Mucosal / Q000235:genetics / Q000276:immunology; D018655:Lymphocyte Count; D064307:Microbiota; D010950:Plasma Cells / Q000276:immunology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D051192:Receptors, Pattern Recognition / Q000235:genetics*; D013552:Swine; D014886:Weaning
chemical_list: D012336:RNA, Ribosomal, 16S; D051192:Receptors, Pattern Recognition
keywords: Intestine; Microbiota; Pattern recognition receptors; Weaned piglets