Pig fecal microbiota during early stages of production and associations with sow microbiota, genotype, and growth performance
The objective of this thesis was to investigate interplays between piglet fecal, sow fecal/vaginal microbiota, pig genetics, and growth performance. The fecal microbiota was analyzed from samples collected from 360 piglets reared under raised without antibiotics or conventional systems at four timepoints from birth to post-weaning from nine farrowing sources in Ontario and Quebec. Additionally, the microbiota of fecal and vaginal samples collected from sows were analyzed. Piglets were genotyped for a panel of ~63 000 single nucleotide variants, and their growth performance during pre-weaning and growing stage was measured. Three successive clusters of microbiota were identified across piglet early life. Further, sow microbes accounted for ~30 % of microbes found in piglet fecal microbiota. Lastly, genome-wide association studies identified associations between pig genotype and microbiota diversity, and interactions between microbiota and genotype on pig performance. These findings may improve swine performance by broadly characterizing piglet microbiota.