Wang Xungang, Zhang Qian, Guo Tongqing, Li Shanshan, Jia Yuna, Xu Shixiao
Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, 810008, China.
University of Chinese Academy of Sciences, Beijing, China.
J Anim Sci Biotechnol. 2025 Sep 2;16(1):122. doi: 10.1186/s40104-025-01259-w.
As an indigenous livestock species on the Tibetan Plateau, Tibetan sheep exhibit remarkable adaptability to low temperatures and nutrient-scarce environments. During the cold season, Tibetan sheep are typically managed under two feeding regimes: barn feeding (BF) and traditional grazing (TG). However, the molecular mechanisms underlying their adaptation to these distinct management strategies remain unclear. This study aimed to investigate the adaptive strategies of rumen function in Tibetan sheep to cold-season feeding regimes by integrating analyses of rumen morphology, microbiome, metabolome, and transcriptome. Twelve healthy Tibetan sheep with similar body weights were assigned into two groups (BF vs. TG). At the end of the experiment, rumen tissues were subjected to histological observation. Multi-omics techniques were employed to evaluate the effects of cold-season feeding regimes on rumen function in Tibetan sheep.
The ruminal papilla height, width, and muscular thickness were significantly higher in BF group. The relative abundances of Actinobacteria and Succiniclasticum were significantly elevated in the rumen of BF group, whereas Rikenellaceae, Gracilibacteria, and Lachnospiraceae showed higher abundances in the TG group. Metabolomic analysis identified 19 differential metabolites between the two groups, including upregulated compounds in BF group (fumaric acid, maltose, L-phenylalanine, and L-alanine) and TG group (e.g., phenylacetic acid, salicyluric acid and ferulic acid). These metabolites were predominantly enriched in phenylalanine metabolism, alanine, aspartate and glutamate metabolism, and phenylalanine, tyrosine and tryptophan biosynthesis pathways. Additionally, 210 differentially expressed genes (DEGs) were identified in rumen epithelium: 100 upregulated DEGs in the BF group were enriched in nutrient metabolism-related pathways (e.g., fatty acid degradation and PPAR signaling pathway), while 110 upregulated DEGs in the TG group were associated with immune-related pathways (e.g., p53 signaling pathway and glutathione metabolism).
Among these, we observed distinct rumen functional responses to different cold-season feeding regimes in Tibetan sheep and revealed energy allocation strategies mediated by host-microbe interactions. In the BF group, Tibetan sheep adopted a "metabolic efficiency-priority" strategy, driving rumen microbiota to maximize energy capture from high-nutrient diets to support host growth. In contrast, the TG group exhibited an "environmental adaptation-priority" strategy, where rumen microbiota prioritized cellulose degradation and anti-inflammatory functions, reallocating energy toward homeostasis maintenance at the expense of rumen development and growth performance.
作为青藏高原的本土家畜品种，藏羊对低温和营养匮乏的环境表现出显著的适应性。在寒冷季节，藏羊通常采用两种饲养方式：舍饲（BF）和传统放牧（TG）。然而，它们适应这些不同管理策略的分子机制仍不清楚。本研究旨在通过整合瘤胃形态学、微生物组、代谢组和转录组分析，探究藏羊瘤胃功能对寒冷季节饲养方式的适应性策略。将12只体重相近的健康藏羊分为两组（BF组与TG组）。实验结束时，对瘤胃组织进行组织学观察。采用多组学技术评估寒冷季节饲养方式对藏羊瘤胃功能的影响。
BF组瘤胃乳头高度、宽度和肌肉厚度显著更高。BF组瘤胃中放线菌和琥珀酸分解菌的相对丰度显著升高，而理研菌科、薄壁菌门和毛螺菌科在TG组中丰度更高。代谢组分析确定了两组之间的19种差异代谢物，包括BF组上调的化合物（富马酸、麦芽糖、L-苯丙氨酸和L-丙氨酸）和TG组上调的化合物（如苯乙酸、水杨尿酸和阿魏酸）。这些代谢物主要富集在苯丙氨酸代谢、丙氨酸、天冬氨酸和谷氨酸代谢以及苯丙氨酸、酪氨酸和色氨酸生物合成途径中。此外，在瘤胃上皮中鉴定出210个差异表达基因（DEG）：BF组上调的100个DEG富集在营养代谢相关途径（如脂肪酸降解和PPAR信号通路）中，而TG组上调的110个DEG与免疫相关途径（如p53信号通路和谷胱甘肽代谢）相关。
其中，我们观察到藏羊对不同寒冷季节饲养方式有明显的瘤胃功能反应，并揭示了宿主-微生物相互作用介导的能量分配策略。在BF组中，藏羊采用了“代谢效率优先”策略，驱动瘤胃微生物群从高营养日粮中最大限度地捕获能量以支持宿主生长。相比之下，TG组表现出“环境适应优先”策略，其中瘤胃微生物群优先进行纤维素降解和抗炎功能，以牺牲瘤胃发育和生长性能为代价将能量重新分配用于维持体内平衡。
