Gastrointestinal microbiota and mucosal immune gene expression in neonatal pigs reared in a cross-fostering model.

Cross fostering is employed to equalize the number of piglet between litters ensuring colostrum intake for their survival and growth. However, little is known about the impact of cross fostering on the intestinal microbiota and mucosal immune gene expression of the neonatal pig. The objective of this study was to determine the influence of maternal microbial communities on the gastrointestinal (GI) microbiota and mucosal immune gene expression in young pigs reared in a cross-fostering model. Piglets were given high quality colostrum from birth dam or foster dam upon birth. Twenty-four piglets were randomly assigned at birth to 1 of 3 treatments according to colostrum source and postcolostral milk feeding during, as follow: treatment 1 (n = 8), received colostrum and post-colostral milk feeding from their own dam; treatment 2 (n = 8), received colostrum from foster dam and returned to their own dam for post-colostral milk feeding; and treatment 3 (n = 8), received colostrum and post-colostral milk feeding from foster dam. Genomic DNA was extracted, and the V1-V3 hypervariable region of the bacterial 16S rRNA gene was amplified and sequenced using the Illumina MiSeq platform. Quantitative real-time PCR analysis was also performed to quantify the expression of toll-like receptors (TLR) 2, TLR 4, TLR 10, tumor necrosis factor alpha (TNFα), interferon gamma (IFNγ), and interleukin (IL) 4 and IL 10. Data analysis revealed that microbial communities were varied according to the GI biogeographical location, with colon being the most diverse section. Bacterial communities in both maternal colostrum and vaginal samples were significantly associated with those present in the fecal samples of piglets. Cross-fostering did not affect bacterial communities present in the piglet GI tract. However, the mRNA expression of TLR and inflammatory cytokines changed (P < 0.05) with biogeographical location in the GI tract. Higher mRNA expression of TLR and inflammatory cytokines was observed in ileum and ileum associated lymph tissues. This study suggests an impact of colostrum and maternal microbial communities on the microbiota development and mucosal immune gene expression in the newly born piglet. This study revealed novel information about the distribution and expression patterns of TLR and inflammatory cytokines in the GI tract of the young pig. Future studies are needed to determine the role and clinical importance of the mucosal microbiota and mucosal gene expression in health, productivity, and susceptibility to the development of GI disease, in piglets.

Biogeographical Differences in the Influence of Maternal Microbial Sources on the Early Successional Development of the Bovine Neonatal Gastrointestinal tract.

The impact of maternal microbial influences on the early choreography of the neonatal calf microbiome were investigated. Luminal content and mucosal scraping samples were collected from ten locations in the calf gastrointestinal tract (GIT) over the first 21 days of life, along with postpartum maternal colostrum, udder skin, and vaginal scrapings. Microbiota were found to vary by anatomical location, between the lumen and mucosa at each GIT location, and differentially enriched for maternal vaginal, skin, and colostral microbiota. Most calf sample sites exhibited a gradual increase in α-diversity over the 21 days beginning the first few days after birth. The relative abundance of Firmicutes was greater in the proximal GIT, while Bacteroidetes were greater in the distal GIT. Proteobacteria exhibited greater relative abundances in mucosal scrapings relative to luminal content. Forty-six percent of calf luminal microbes and 41% of mucosal microbes were observed in at-least one maternal source, with the majority being shared with microbes on the skin of the udder. The vaginal microbiota were found to harbor and uniquely share many common and well-described fibrolytic rumen bacteria, as well as methanogenic archaea, potentially indicating a role for the vagina in populating the developing rumen and reticulum with microbes important to the nutrition of the adult animal.