UNASSIGNED: In this study, we determined the rumen bacterial profile and rumen fermentation parameters to reveal the bacterial profiles and predictive functions among breeds and diets with four different energy levels, as well as the correlation between bacterial profiles and rumen fermentation characteristics.
UNASSIGNED: The results showed that the rumen total volatile fatty acids (VFAs), acetate, butyrate, total branched-chain VFAs, iso-butyrate, and iso-valerate were higher in T-sheep than H-sheep. The alpha diversity of ruminal bacteria is not affected by dietary energy, but it shows a distinction between the sheep breeds. Specifically, T-sheep rumen bacteria exhibit higher alpha diversity than H-sheep. The beta diversity of ruminal bacteria is not influenced by dietary energy or sheep breeds, indicating similar communities of ruminal bacteria between different diets and sheep breeds. The phyla of Bacteroidetes and Firmicutes predominate in the rumen, with a higher relative abundance of Firmicutes observed in T-sheep than H-sheep. The two most abundant genera in the rumen were Prevotella 1 and Rikenellaceae RC9 gut group. Prevotella 1 is the predominant bacterial genus in the rumen of H-sheep, while the Rikenellaceae RC9 gut group dominates in the rumen of T-sheep. Microbial co-occurrence network analysis reveals that variations in rumen fermentation characteristics result from differences in module abundance, with a higher abundance of VFA-producing modules observed in the rumen of T-sheep. Microbial function prediction analysis showed that dietary energy rarely alters the functional composition of rumen bacteria. However, there were differences in the functions of rumen bacteria between sheep breeds, with T-sheep showing a greater emphasis on energy metabolism-related functions, while H-sheep showed a greater emphasis on protein metabolism-related functions.
UNASSIGNED: These findings provide evidence of the special rumen microbial community that helps T-sheep efficiently obtain energy from low-protein and low-energy diets, enabling them to survive in the extreme environment of the Qinghai-Tibet Plateau.
■在这项研究中,我们确定了瘤胃细菌谱和瘤胃发酵参数,以揭示四种不同能量水平的品种和饮食之间的细菌谱和预测功能,以及细菌谱与瘤胃发酵特性的相关性。
■结果表明瘤胃总挥发性脂肪酸(VFA),醋酸盐,丁酸盐,总支链VFA,异丁酸,T型羊和异戊酸高于H型羊。瘤胃细菌的α多样性不受日粮能量的影响,但它显示了绵羊品种之间的区别。具体来说,T-绵羊瘤胃细菌比H-绵羊表现出更高的α多样性。瘤胃细菌的β多样性不受饮食能量或绵羊品种的影响,表明不同饮食和绵羊品种之间的瘤胃细菌群落相似。在瘤胃中,拟杆菌和厚壁菌的门占主导地位,在T绵羊中观察到的Firmicutes的相对丰度高于H绵羊。瘤胃中最丰富的两个属是Prevotella1和RkenellaceaeRC9肠组。Prevotella1是H-绵羊瘤胃中的主要细菌属,而RikenellaceaeRC9肠组在T羊的瘤胃中占主导地位。微生物共生网络分析表明,瘤胃发酵特性的变化是由模块丰度的差异引起的,在T羊的瘤胃中观察到较高丰度的VFA产生模块。微生物功能预测分析表明,日粮能量很少改变瘤胃细菌的功能组成。然而,绵羊品种间瘤胃细菌的功能存在差异,与T-绵羊表现出更多的强调能量代谢相关的功能,而H-绵羊对蛋白质代谢相关功能的重视程度更高。
■这些发现提供了特殊的瘤胃微生物群落的证据,该群落可帮助T羊从低蛋白和低能量的饮食中有效地获取能量,使它们能够在青藏高原的极端环境中生存。