The dynamics of the community structure and composition of the dairy cow fecal bacterial communities during early lactation is unclear, therefore this study was conducted to characterize the fecal bacterial communities in dairy cows during early lactation using 16S rRNA gene sequencing. Feces were sampled from 20 healthy fresh Holstein dairy cows on day 1 (Fresh1d group) and day 14 (Fresh14d group) after calving. After calving, cows were fed the same fresh diet. The dominant phyla Firmicutes and Proteobacteria were decreased (P ≤ 0.01) with lactating progress and phyla Bacteroidetes were increased (P = 0.008) with lactating progress and dietary transition. At family level, the predominant families were Ruminococcaceae (35.23%), Lachnospiraceae (11.46%), Rikenellaceae (10.44%) and Prevotellaceae (6.89%). A total of 14 genera were different between fecal samples from Fresh1d and Fresh14d, included the predominant genera, such as Ruminococcaceae_UCG-005 (P = 0.008), Rikenellaceae_RC9_gut_group (P = 0.043) and Christensenellaceae_R-7_group (P = 0.008). All fecal bacterial communities shared members of the genera Ruminococcaceae_UCG-005, Bacteroides and Rikenellaceae_RC9_gut_group. These findings help to improve our understanding of the composition and structure of the fecal microbial community in fresh cows and may provide insight into bacterial adaptation time and dietary in lactating cows.

中文翻译：

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泌乳早期奶牛粪便细菌群落的动态变化。

泌乳早期奶牛粪便细菌群落的群落结构和组成动态尚不清楚，因此本研究旨在使用 16S rRNA 基因测序来表征泌乳早期奶牛的粪便细菌群落。在产犊后第 1 天（Fresh1d 组）和第 14 天（Fresh14d 组）从 20 头健康的新鲜荷斯坦奶牛的粪便中取样。产犊后，奶牛喂食相同的新鲜饲料。 随着泌乳进展，优势门厚壁菌门和变形菌门减少（P ≤ 0.01），而 随着泌乳进展和饮食转变，拟杆菌门增加（P = 0.008）。在家庭层面，主要的家庭是Ruminococcaceae（35.23％），毛螺（11.46％），Rikenellaceae（10.44％）和Prevotellaceae（6.89％）。总共14个属的来自Fresh1d和Fresh14d粪便样品之间是不同的，包括主要的属，如Ruminococcaceae_UCG - 005（P  = 0.008），Rikenellaceae_RC9_gut_group（P  = 0.043）和Christensenellaceae_R - 7_group（P  = 0.008）。所有粪便细菌群落共有瘤胃球菌科_UCG - 005、拟杆菌属和Rikenellaceae_RC9_gut_group。这些发现有助于提高我们对新鲜奶牛粪便微生物群落组成和结构的理解，并可能为了解泌乳奶牛的细菌适应时间和饮食提供见解。