Integrating multi-omics to characterize the dynamics of rumen microorganisms and metabolites in Angus cattle at...

The development of the bovine rumen microbiome is crucial for growth, yet the dynamic interactions between the microbiome and metabolome during key growth stages remain poorly understood. This study aims to integrate metagenomics and metabolomics approaches to decipher the stage-specific patterns of rumen microbial community and metabolite changes in castrated Angus cattle at three critical growth stages (6, 12, and 18 months of age), and to elucidate their associations with host growth performance. We collected rumen fluid samples from 24 Angus steers (8 per age group) reared under standardized conditions and performed metagenomic and non-targeted metabolomic analyses. Integrated analysis revealed distinct rumen ecosystem succession patterns: multiple species represented by Prevotella_sp._ne3005 dominated at 6 months, Fibrobacter_succinogenes showed significantly increased abundance at 12 months, and Methanobrevibacter_millerae exhibited the most pronounced enrichment at 18 months. Concurrently, key metabolites 12,13-Dihydroxyoleic Acid, Delta-12-Pgj2, and Cortisol exhibited a significant positive correlation with age. Further Pearson correlation analysis revealed strong correlations between the 18-month-enriched characteristic microorganism Methanobrevibacter_millerae and key metabolites (12,13-Dihydroxyoleic Acid, Delta-12-Pgj2, and Cortisol) as well as higher body weight. This study delineates a dynamic map of synergistic interactions between the rumen microbiome and metabolome, confirming their close association with host growth performance. This work provides a systematic multi-omics framework for understanding rumen development in ruminants and identifies potential targets for optimizing beef cattle production performance through microbial or metabolic interventions.