Synergistic Effects of High-Fiber Diet and N-Carbamylglutamate on Sow Reproductive Performance via Uterine Microbiota-PI3K/Akt Modulation

Uterine microbiome is crucial for embryo implantation and pregnancy by creating a favorable environment. While both high fiber diet and N-Carbamylglutamate (NCG) have been individually demonstrated to enhance reproductive efficiency in sows, their potential synergistic effects and the involvement of uterine microbial mechanisms remain largely unexplored. In this study, we employed a multi-omics approach to investigate the synergistic impact of a high-fiber diet combined with 0.05% NCG on reproductive performance in Landrace × Yorkshire sows. The study revealed that high fiber with NCG (H+N) significantly increased FSH activity and T-AOC content in serum. Metagenomic analysis indicated an increased abundance of Clostridium disporicum in the uterine microbiota. Plasma metabolomics identified key metabolites- hydroxylysine-as mediators of H+N intervention, which positively correlated with elevated Clostridium disporicum abundance. Subsequent transcriptomic profiling revealed activation of the PI3K-Akt signaling pathway, which was associated with increased FSH activity and T-AOC content. Overall, these findings demonstrated that the supplementation of a high-fiber diet with NCG enhances sow reproductive efficiency by modulating the uterine microbiota (specifically Clostridium disporicum), increasing hydroxylysine production, and activating the PI3K-Akt signaling pathway, thereby improving hormonal activity and antioxidant capacity.