| dc.description.abstract | The pioneer microbiome is the initial colonization of microbiological organisms that has lifelong implications for animal health and performance. The objective was to quantify maternal and environmental contributors to the piglet’s pioneer microbiome. Piglets born from five gilts were individually identified, weighed, and selected for microbiome analysis. Environmental samples were collected from the farrowing crate prior to gilt introduction (Empty Crate) and after gilts were moved in (Full Crate). Maternal samples were collected from the birth canal during farrowing (Birth Canal) and colostrum was collected from each gilt during farrowing (Colostrum). The piglet’s rectum was swabbed on days 0 (pre-suckle), 3, and 10 post-farrowing and at weaning (21.6 ± 1.0 days post-farrowing). Swabs and colostrum were stored in sterile tubes at - 80°C until sequencing. Bacterial DNA extraction and genome sequencing targeted the V4 hypervariable region of the 16S rRNA gene. Statistical analyses were conducted using PROC GLM and PROC REG in SAS 9.4. Maternal and environmental sources did not differ for the phyla Firmicutes and Proteobacteria. Yet the piglet microbiome shifted from birth to weaning. The relative abundance of phylum Firmicutes was lower on day 3 compared to day 0 and at weaning but did not differ from day 10. Within the phylum Firmicutes, Lactobacillus and Clostridium genera were greater on day 3 compared to day 0, 10, and at weaning. The relative abundance of phylum Proteobacteria, and the relative abundance of genus Escherichia within this phylum, were greater on day 3 compared to day 0, 10, and at weaning. Multiple regression analyses indicated that Birth Canal explained 51.6% of the variation observed in piglet day 0 microbiome and 6.5% of the variation in the piglet day 10 microbiome. The piglet day 0 microbiome explained 10.0% of the variation observed in day 3 microbiome and 15.6% of the day 10 microbiome. Finally, day 10 microbiome explained 58.6% of the variation observed in the piglet microbiome at weaning. The microbiome of Colostrum and the farrowing crate did not impact piglet microbiome. Results indicate the piglet pioneer microbiome is largely influenced by the microbiome of the birth canal and may be largely established by 10 days of age. | |
