Compositional and functional comparisons of the microbiota in the colostrum and mature milk of dairy goats

Abstract BackgroundGoat milk is essential for the initial development of kids by providing a great source of commensal bacteria. Here we analyzed the microbiota of goat colostrum which was collected daily for five days post delivery and mature milk collected at the 7th, 10th, 20nd, 30th, 40th, 50th and 60th days, respectively, from three farms of Shaanxi province.ResultsThe result showed that microbial alpha diversity was higher in the mature milk compared with that in the colostrum. According to taxonomy results, Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were the predominant bacteria phyla in both colostrum and mature milk. In addition, lactation stage noticeably influenced the composition of milk microbiota. Specifically, Novosphingobium, Brachybacterium, Psychrobacter, Lactobacillus, Yersinia, Roseatelesand, Rothia, Sanguibacter, Cloacibacterium, Variovorax, Sphingobacterium, Coxiella were enriched in the colostrum while Georgenia, Peptostreptococcus, Bacteroidales, Yaniella, Planomicrobium, Cloacibacterium, Azospirillum, Turicibacter, Cupriavidus, Herbaspirillum, Rhodobacteraceae, Aeromonadales were the dominant genera in the mature milk. The enriched metabolic functions of the goat milk microbiota were predicted by PICRUSt and classified by KEGG patway. Moreover, the abundances of the environmental information processing, cellular processes pathway, genetic information processing pathway, organismal systems pathway and metabolism pathway were significantly different between microbiota of colostrum and mature milk.ConclusionsAltogether, our study disclosed the significant difference between the microbial communities of colostrum and mature milk and provided grounds for further research in dairy microbiology.