Heritable gut microbiota decreases fat accumulation in pregnant sows and optimizes gestational outcomes

This study investigates the interplay between host genetics and gut microbiota in regulating fat deposition and reproductive outcomes in sows. Integrating multiomics data from 348 Yorkshire sows-including whole-genome sequencing, 16S rRNA sequencing, and metabolomic profiling-we identified 37 microbial taxa significantly associated with thick backfat (TBP) through microbiome-wide association studies (MWAS). Microbial genome-wide association analysis (mGWAS) revealed heritable genera, including Ezakiella and Corynebacterium, and implicated host genes such as MED17 and VSTM5 in microbial modulation. Concurrently, genome-wide association studies (GWAS) identified MC4R and MEDAG as candidate genes directly influencing TBP. Metabolomic analysis highlighted acetate, a short-chain fatty acid, as a key mediator in host adipogenesis. Functional validation in experimental models demonstrated that exogenous acetate supplementation alters lipid metabolism and enhances reproductive performance. These findings elucidate a mechanistic axis wherein host genetics shape gut microbial composition, which in turn modulates fat metabolism via acetate production, ultimately affecting pregnancy outcomes. This integrated approach provides insights into host-microbe co-regulation of metabolic traits and highlights potential targets for improving reproductive efficiency in livestock.