32 Longitudinal investigation reveal changes in microbiome for lactating sows.

Abstract The communities within the gastrointestinal tract play crucial roles in maintaining the function and health of the host. Stable gut microbial communities have substantial roles in regulating important biological functions such as nutrient absorption, metabolism, and disease resistance. The relationship of the gut microbiome and environmental conditions have been noted to have profound impacts on the individual. Unstable communities can enter dysbiosis typically featuring a bloom of pathobionts, loss of commensals, and loss of diversity. Studies have characterized the relationship between pregnancy and gut microbiome in humans, but few have illustrated changes in microbial composition along lactation in sows exposed to heat stress. The objective of this study is to profile changes in the gut microbiome of lactating sows. A total of 1,645 multiparous lactating sows (Large White × Landrace) were housed within individual farrowing crates (2.0 × 1.8 m). Fecal (gut) microbiome samples were collected at four physiological time points: pre-farrowing, farrowing, post farrowing 1 and post farrowing 2. A linear mixed effects model was used to test the significance of physiological stage on alpha diversity. There was a significant difference in alpha diversity (P< 0.001), except between post farrowing 1 and post farrowing 2. Physiological stage also significantly influenced the community structure (beta diversity) of gut microbiota (P< 0.001). Further analysis utilized sows that experience heat stress on date of farrowing to detect if there was variation in gut microbiome composition amongst individuals. Results displayed significant differences in alpha diversity (P< 0.05) and composition amongst individuals. These results show that microbiome data can be used as a bridging component along with genetic selection of climate tolerant sows so they can better manage heat stress while maintaining productivity that will aid in feeding the growing population.