Multi-omics analysis reveals circadian disruption of rumen microbiota and serum metabolites in Tibetan sheep under transport stress
摘要
Off-site fattening of Tibetan sheep is a key strategy to mitigate the effects of high-altitude grassland degradation and winter forage scarcity, promoting sustainable development in plateau animal husbandry. However, transport stress (TS) presents a significant challenge to realizing its benefits. The mechanism by which TS affects the health of Tibetan sheep by regulating rumen microbial and serum metabolite rhythmic changes remains unclear.
MethodsThis study selected six healthy male Tibetan sheep, aged seven months and of comparable body weight, for the transport experiment. Blood and rumen fluid samples were collected at four-hour intervals during 24-hour periods pre-transport (CON) and post-transport (TS) for serum indicators, serum metabolome, and rumen microbiome analyses.
ResultThe results showed that TS significantly increased serum concentrations of cortisol (COR), melatonin (MT), lipopolysaccharide-binding protein (LBP), serum amyloid A (SAA), and non-esterified fatty acid (NEFA), while significantly decreasing glucose (GLU), total antioxidant capacity (T-AOC), and glutathione peroxidase (GPx) (P < 0.05). Furthermore, the circadian rhythms of COR, MT, LBP, SAA, NEFA, and GPx were significantly disrupted (ADJ.P < 0.05). TS reduced the proportion of rumen microbial circadian rhythms from 3.46% to 1.99%, with Prevotella, Butyrivibrio, and Ruminococcus losing their circadian rhythmicity in the TS phase (ADJ.P < 0.05). Additionally, TS decreased the proportion of circadian rhythm-regulated serum metabolites from 51.74% to 29.51%. In the TS phase, rhythmically regulated metabolites, including 3’,5’-cyclic AMP, fumarate, dopamine, glutathione, and angiotensin (1–7), were enriched in pathways such as oxidative phosphorylation, retinol metabolism, and tryptophan metabolism. Multi-omics analyses demonstrated significant correlations between Ruminococcus and energy metabolites (malic acid, 3’,5’-cyclic AMP, fumarate, NEFA), and between Butyrivibrio, Anaeroplasma, and inflammatory/antioxidant markers (glutathione, SAA, LBP). In conclusion, this study reveals that TS induces a homeostatic imbalance in Tibetan sheep by disrupting the circadian rhythms of both the rumen microbiota and host metabolism. These findings provide a theoretical basis and molecular targets for developing interventions to alleviate TS in livestock.