Integrated metabolomic and transcriptomic analysis reveals digestive tract adaptations to high altitude in Bayanbulak sheep.

Introduction: High-altitude adaptation in Bayanbulak sheep may modulate digestive tract functions. This study investigated differences in digestive tract metabolites between Bayanbulak sheep at high altitude (2,400-4,400 m) and Turpan black sheep at low altitude (-154 m). We performed untargeted metabolomics analysis on ruminal fluid, small intestinal contents, and fecal metabolites, measured serum biochemical parameters, and examined skin tissue morphology. Differential gene expression in ruminal fluid was analyzed using RNA-seq. Key findings include: (1) Bayanbulak sheep showed significantly higher including total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT), interferon-γ (IFN-γ), interleukin-2 (IL-2), total cholesterol, glucose, and triglyceride levels compared to Turpan black sheep ( Conclusion: Bayanbulak sheep adapt to high-altitude hypoxia and thermal stress through epidermal thickening and synergistic interactions between blood and digestive tract metabolites. These adjustments enhance antioxidant capacity, energy reserves, and immune function, offering a robust model for high-altitude adaptation.