为全面了解羊乳中细菌多样性，对陕西关中地区杨凌、宝鸡和渭南三个牧场羊乳样品中微生物宏基因组DNA的16S rRNA基因V3-V4区进行扩增、高通量测序。研究共获得225424条高质量序列，平均每个样品聚成673个OTUs。对不同地区羊乳中细菌群落构成分析显示，所有羊乳样品中细菌门有27种，Proteobacteria为陕西关中地区羊乳中的优势菌群门，在渭南地区所占比例最高，为91.15%，在杨凌和宝鸡地区分别占62.44%和60.33%；细菌属有354种，Enterobacter是关中地区羊乳中的优势细菌属，三个地区所占比例分别为37.41%、33.82%和2.87%；细菌种有826种，P.aeruginosa为陕西关中地区的优势菌株，在三个地区分别占1.17%、0.81%和21.8%，且渭南地区的P.aeruginosa含量显著高于其他两个地区。不同地区羊乳样品细菌群体间的多样性分析表明，杨凌和宝鸡这两个地区羊乳中细菌群落丰富度和多样性较高，渭南地区羊乳中细菌群落丰富度和多样性较低。三个地区间羊乳中细菌分布有一定的差别，但样品之间微生物群落结构差距不大，有一定的相似性。

To fully understand the bacterial diversity and community structure of goat milk, V3-V4 region of bacterial 16S rRNA gene in metagenomic DNA of goats’ milk samples from Yangling, Baoji and Weinan region of Shaanxi Province were analyzed using high-throughput sequencing. A total of 225424 high-quality sequences were obtained, with an average of 673 OTUs per sample. The analysis of bacterial communities in goat milk from different regions showed that there are 27 bacterial phylum,Proteobacteriadominated the microbiota of all goat milk samples in Guanzhong region of Shaanxi Province, and Weinan area accounted for the greatest proportion with 91.15%, Yangling and Baoji area accounted for 62.44% and 60.33%, respectively. There are 354 bacteria genus, the dominant microorganisms of bacteria were identified asEnterobacter, the proportion in the three areas were 37.41%, 33.82% and 2.87% respectively. At the species level,Pseudomonas aeruginosawere dominant in 826 bacteria species, the proportion in the three areas were 7.96%, 4.34% and 3.20%, respectively, and Weinan area had significantly higher contents ofPseudomonas aeruginosathan Yanglin area and Baoji area. The diversity analysis of bacterial population indicated that bacterial community of goat milk in Yangling and Baoji areas had a higher richness and diversity, while Weinan areas had a lower richness and diversity. The bacteria distribution in diverse goat milk had certain difference, while the gaps in bacterial community structure were smaller, exhibited substantial similarities.