Biochanin A improves nitrogen utilization efficiency by regulating ruminal microbial community in dairy goats.

BACKGROUND: Rumen microbial nitrogen metabolism is crucial for animal health, productivity, and environmental sustainability in ruminants. Natural products like biochanin A are garnering interest as potential feed additives due to their beneficial effects and safety profiles. Here, we collected total mixed diet, plasma, milk, urine, and feces samples of dairy goats to evaluate the impact of biochanin A on nitrogen metabolism and elucidated regulatory mechanisms of nitrogen metabolism using multi-omics approaches by analyzing plasma metabolites and ruminal microbial communities. RESULTS: Supplementation with biochanin A significantly enhanced nitrogen utilization efficiency of dairy goats. Plasma metabolomics revealed that biochanin A altered pathways related to amino acid biosynthesis/metabolism and glycolysis/gluconeogenesis. In the rumen, biochanin A enriched microbial strains from the families Selenomonadaceae and Aminobacteriaceae. Up-regulated proteins predominantly associated with glycolysis were identified by metaproteomics. Integrated metagenomic and metaproteomic analyses demonstrated that biochanin A positively influenced carbohydrate metabolism, amino acid metabolism, and energy metabolism pathways. CONCLUSION: Biochanin A enhances nitrogen metabolism by regulating rumen microbial community function, supporting its potential as a natural feed additive to improve nitrogen utilization of ruminants. Video Abstract.