He Shichun, Yuan Zaimei, Dai Sifan, Wang Zibei, Zhao Shusheng, Wang Rongjiao, Li Qing, Mao Huaming, Wu Dongwang
Key Laboratory of Animal Nutrition and Feed Science of Yunnan Province, Yunnan Agricultural University, Kunming, China.
Kunming Animal Disease Prevention and Control Center, Kunming, China.
Front Vet Sci. 2024 Apr 5;11:1365300. doi: 10.3389/fvets.2024.1365300. eCollection 2024.
Amidst the challenging environmental conditions characterized by low oxygen levels and cold temperatures on the plateau, alterations in nutrient supply emerge as pivotal factors influencing the survival and reproduction of yaks. Intensive feeding stands out as a substantial mechanism for nutrient provision, initiating discernible changes in the host's rumen flora. Within the extreme natural conditions prevailing in the plateau area of northwest Yunnan, China, there exists a con-strained comprehension of the variations in rumen microflora, fermentation parameters, and growth responses exhibited by yaks subjected to intensive feeding.
This study employs 16S rRNA and ITS sequencing methods to scrutinize the rumen flora of yaks engaged in both natural grazing (G) and intensive feeding (F) on the plateau.
The outcomes unveil that, during the severe winter season, yaks adeptly modulate the abundance and diversity of rumen flora in response to dietary modifications under intensive feeding, aiming to optimize the efficient utilization of dietary fiber and energy. Principal Coordinate Analysis (PCoA) illustrates a substantial alteration in the rumen microbial community of naturally grazing yaks when exposed to intensive feeding. The natural grazing group manifests a higher prevalence of Firmicutes and Bacteroidetes, while the intensive feeding group exhibits heightened levels of in the rumen. The _ RC9 _ gut_ group, associated with mycobacteria, prevails more abundantly in the natural grazing setting. PICRUSt2 analysis indicates that intensive feeding induces bacterial gene overexpression linked to protein metabolism. Rumen fungi showcase heightened diversity under intensification. Intensive feeding results in an augmented abundance of non-fiber-degrading bacteria and semi-fiber-degrading bacteria, accompanied by elevated concentrations of Volatile Fatty Acids (VFA).
These findings yield novel insights into the shifts in the rumen microflora of yaks acclimated to intensive feeding in high-altitude environments, provide an important reference for the nutritional regulation of supplemental feeding of natural grazing yaks in the cold season, ultimately contributing to their enhanced growth.
在高原地区低氧和低温的挑战性环境条件下，营养供应的变化成为影响牦牛生存和繁殖的关键因素。强化饲养是提供营养的重要机制，会引发宿主瘤胃菌群的明显变化。在中国云南西北部高原地区极端的自然条件下，对于接受强化饲养的牦牛瘤胃微生物群、发酵参数和生长反应的变化，人们的了解有限。
本研究采用16S rRNA和ITS测序方法，对高原地区自然放牧（G）和强化饲养（F）的牦牛瘤胃菌群进行检测。
结果表明，在严酷的冬季，牦牛会根据强化饲养下的饮食变化，巧妙地调节瘤胃菌群的丰度和多样性，以优化膳食纤维和能量的有效利用。主坐标分析（PCoA）表明，自然放牧的牦牛在接受强化饲养时，瘤胃微生物群落发生了显著变化。自然放牧组中厚壁菌门和拟杆菌门的比例较高，而强化饲养组瘤胃中的[此处原文缺失部分内容]水平较高。与分枝杆菌相关的_RC9_肠道菌群在自然放牧环境中更为丰富。PICRUSt2分析表明，强化饲养会诱导与蛋白质代谢相关的细菌基因过度表达。强化饲养下瘤胃真菌的多样性增加。强化饲养导致非纤维降解菌和半纤维降解菌的丰度增加，同时挥发性脂肪酸（VFA）浓度升高。
这些发现为适应高海拔环境强化饲养的牦牛瘤胃微生物群变化提供了新的见解，为寒冷季节自然放牧牦牛补饲的营养调控提供了重要参考，最终有助于促进它们的生长。
