山谷型藏羊公羊瘤胃和粪便微生物多样性研究

Study on bacterial diversity of rumen and feces of Valley-typed Tibet ram

为了研究青藏高原山谷型藏羊公羊胃肠道微生物组成结构,试验采集了10只放牧+补饲饲养方式下的周岁山谷型藏羊公羊的瘤胃和直肠内容物(指粪便),分别提取其基因组DNA,采用16S rDNA V3~V4扩增子高通量测序技术分析了瘤胃和粪便样品微生物门和属水平组成结构、标志微生物、α和β多样性及微生物功能。结果表明:山谷型藏羊瘤胃和粪便样品共得到5 383个分类操作单元(operational taxanomic units, OTUs),其中2 144个OTUs为瘤胃样品所特有,1 860个OTUs为粪便样品特有,1 379个为二者共有。瘤胃微生物优势菌门为厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)和浮霉菌门(Planctomycetes),相对丰度分别为53.2%、34.9%和3.1%;优势菌属为理研菌科_RC9_肠道菌群(Rikenellaceae_RC9_gut_group)和普式菌属_1(Prevotella_1),相对丰度分别为13.5%和12.0%。粪便微生物优势菌门为拟杆菌门、厚壁菌门和疣微菌门(Verrucomicrobia),相对丰度分别为47.4%、25.3%和16.9%;优势菌属为艾克曼菌属(Akkermansia)和克里斯滕森菌科_R7菌群(Christensenellaceae_R7_group),相对丰度分别为15.6%和7.3%。山谷型藏羊瘤胃和粪便样品的标志微生物均为拟杆菌门和厚壁菌门,且瘤胃和粪便样品微生物α和β多样性差异明显,主要功能均为碳水化合物代谢(carbohydrate metabolism)、氨基酸代谢(amino acid metabolism)、膜运输(membrane transport)与共同因子和维生素代谢(metabolism of cofactors and vitamins)等。说明山谷型藏羊瘤胃和粪便有各自独特的微生物组成结构。

In order to study the gastrointestinal microbial composition in Valley-typed Tibet ram, rumen and rectal contents(referring to feces) samples of 10 one-year-old Valley-typed Tibet ram were collected, sample DNA was extracted respectively, and then bacterial characteristic at phylum and genus level, marker bacteria, α-diversiy and β-diversity, and bacterial functions in rumen and fecal samples were analysed by high-throughput sequencing technology of V3-V4 regions of 16S rDNA. The results showed that the number of OTU obtained from all samples was 5 383, among which 2 144 OTUs was special in rumen, 1 860 OTUs was special in feces samples, and 1 379 OTUs was shared by samples of rumen and feces.In rumen, Firmicutes, Bacteroidetes and Planctomycetes were the most abundant phyla in rumen, with relative abundance of 53.2%, 34.9% and 3.1%, respectively.The dominant bacterial genera Rikenellaceae_RC9_gut_group and Prevotella_1,whose relative abundance was 13.5% and 12.0%, respectively. In feces, Bacteroidetes, Firmicutes and Verrucomicrobia were the most abundant phyla, whose relative abundance was 47.4%, 25.3% and 16.9%, respectively.The dominant bacterial genera were Akkermansia and Christensenellaceae_R7_group predominated by 15.6% and 7.3%, respectively. Bacteroidetes and Firmicutes were the marker bacteria of rumen and feces samples, and there were significant difference of α-diversity and β-diversity between rumen and feces. Carbohydrate metabolism, amino acid metabolism, membrane transport and metabolism of cofactors and vitamins were the main functions. The results indicated that the rumen and feces of Valley-typed Tibet sheep had their own unique microbial composition.