Table_2_Exploring the temporal dynamics of rumen bacterial and fungal communities in yaks (Bos grunniens) from 5 days after birth to adulthood by full-length 16S and 18S rRNA sequencing.XLSX

The rumen of ruminants is inhabited by complex and diverse microorganisms. Young animals are exposed to a variety of microorganisms from their mother and the environment, and a few colonize and survive in their digestive tracts, forming specific microflora as the young animals grow and develop. In this study, we conducted full-length sequencing of bacterial and fungal communities in the rumen of pastured yaks of different ages (from 5  days after birth to adulthood) using amplified sequencing technology. The results showed that the rumen microflora of Zhongdian yaks changed gradually from 5 to 180  days after birth and tended to stabilize at 2  years of age. The rumen of adult yaks was the most suitable for the growth and reproduction of most bacteria. Bactria diversity of the yak rumen increased gradually from 5  days after birth to adulthood. With the growth of yaks, different dominated bacteria were enriched in different groups, but Prevotella remained highly abundant in all groups. The yak rumen at 90  days of age was the most suitable for the growth and reproduction of most fungi, and 90 days of age could be a cut-off point for the distribution of fungal communities. Fungal Thelebolus was the firstly reported in yak rumen and was enriched in the yak rumen of 90  days after birth. The most abundant and balanced fungal genera were found in adult yaks, and most of them were only detected in adult yaks. Our study reported on the rumen bacterial and fungal communities of Zhongdian yaks grazed at different ages and provided insights into the dynamic changes of dominant microflora with yak growth.

反刍动物的瘤胃中定殖着复杂多样的微生物群落。幼龄反刍动物会从母体与周遭环境中接触到多种微生物，其中少数菌株可在其消化道内定殖存活，并随着幼畜的生长发育逐步形成特异性微生物菌群。本研究采用扩增测序技术，对不同日龄（从出生后5天至成年）的放牧型中甸牦牛（Zhongdian yaks）的瘤胃细菌与真菌群落开展全长测序分析。结果显示，中甸牦牛的瘤胃微生物菌群在出生后5至180天内逐渐发生演替，并在2岁左右趋于稳定。成年牦牛的瘤胃环境最适宜多数细菌的生长与繁殖；牦牛瘤胃的细菌多样性从出生后5天至成年阶段呈逐步上升趋势。随着牦牛的生长发育，不同日龄组的优势细菌类群存在显著差异，但普雷沃氏菌属（Prevotella）在所有组别中均保持较高丰度。出生后90日龄的牦牛瘤胃最适宜多数真菌的生长繁殖，该日龄可作为真菌群落分布的关键分界点。掷囊球菌属（Thelebolus）为首次在牦牛瘤胃中被报道的真菌类群，且在出生后90日龄的牦牛瘤胃中显著富集。成年牦牛的瘤胃中拥有丰度最高且群落结构最均衡的真菌属类，其中多数类群仅在成年牦牛中被检测到。本研究针对不同日龄放牧中甸牦牛的瘤胃细菌与真菌群落进行了系统性分析，揭示了优势微生物菌群随牦牛生长发育的动态变化规律。