Agricultural practises such as conventional and organic farming can potentially affect the microbial communities in milk. In the present study, the bacterial diversity of milk was investigated using high-throughput sequencing on ten organic and ten conventional farms in the Azores, a region where milk production is largely based on year-round grazing systems. The microbiota of milk from both production systems was dominated by , , and . The organic milk showed greater heterogeneity between farms, as reflected in the dispersion of diversity indices and the large variation in the relative abundances of the dominant genera. In contrast, conventionally produced milk showed a high degree of similarity within each season. In the conventional production system, the season also had a strong influence on the bacterial community, but this effect was not observed in the organic milk. The LEfSe analysis identified the genus as significantly ( < 0.05) more abundant in organic milk, but depending on the season, several other genera were identified that distinguished organic milk from conventionally produced milk. Of these, , and were associated with the soil microbiota in organic farming.

中文翻译：

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有机牛奶和常规牛奶细菌群落的比较研究

传统农业和有机农业等农业实践可能会影响牛奶中的微生物群落。在本研究中，通过高通量测序对亚速尔群岛的 10 个有机农场和 10 个传统农场进行了牛奶细菌多样性调查，该地区的牛奶生产主要基于全年放牧系统。两个生产系统的牛奶微生物群均以 、 和 为主。农场之间的有机牛奶表现出更大的异质性，这反映在多样性指数的分散性和优势属相对丰度的巨大变化上。相比之下，传统生产的牛奶在每个季节都表现出高度的相似性。在传统的生产系统中，季节也对细菌群落有很大的影响，但在有机牛奶中没有观察到这种影响。LEfSe 分析确定该属在有机牛奶中含量显着更高（< 0.05），但根据季节的不同，还发现了其他几个属来区分有机牛奶和传统生产的牛奶。其中， 、 和 与有机农业中的土壤微生物群相关。