Transcriptional adaptation of rumen papillae to high-grain diet reveals distinct temporal phases and SARA susceptibility signatures - PubMed
5 hours ago
- #rumen adaptation
- #SARA susceptibility
- #high-grain diet
- Transitioning to a high-grain (HG) diet alters rumen fermentation, increasing short-chain fatty acids (SCFAs) and lowering pH, potentially causing subacute ruminal acidosis (SARA).
- Study analyzed gene expression and metabolomic profiles in rumen papillae during low-grain (LG) and HG diet phases (HG1 and HG4) in SARA-susceptible and resistant cows.
- RNA sequencing identified 955 differentially expressed genes (DEGs), showing biphasic adaptation: moderate changes at HG1 and substantial remodeling at HG4.
- Pathway analysis revealed affected categories: cellular stress response, metabolic adaptation, and protein processing.
- Sterol biosynthesis genes transiently upregulated at HG1, then downregulated at HG4, coinciding with rumen wall thickness and n-butyrate changes.
- Valerate levels at HG1 correlated with tissue remodeling genes at HG4, suggesting delayed epithelial responses.
- SARA-susceptible cows showed persistent transcriptional differences in inflammation, cell structure, and metabolism genes, indicating intrinsic susceptibility.
- Key under-expressed genes in SARA-susceptible cows (CCDC196, MYO7B) may serve as biomarkers for SARA predisposition.
- SARA-resistant cows exhibited more transcriptome-metabolome correlations, indicating coordinated epithelial responses to diet changes.