健康奶牛和乳腺炎奶牛乳汁中微生物组成的特征及差异研究

Study on characteristics and differences of microbial composition in milk of healthy cows and mastitic cows

奶牛乳腺炎的发生与多种病原微生物密切相关,乳汁中菌群特征的分析对建立乳房炎防控体系和提高乳制品质量和安全具有重要意义。本研究通过16S rRNA基因的V3-V4区测序,分析河南省某奶牛场17头健康奶牛和10头乳房炎奶牛乳汁中微生物菌群结构的多样性和丰富度。结果发现,微生物菌群在11个门、24个纲、37个目、82个科和184个属水平上的相对丰度存在显著差异。乳腺炎奶牛乳汁中微生物菌群结构的多样性和丰富度显著低于健康奶牛乳汁,在乳腺炎奶牛乳汁中厚壁菌门、变形菌门、放线菌门的相对丰度较高。乳腺感染后,变形菌门、软壁菌门的丰度显著降低;互养菌门的丰度显著升高。乳腺炎奶牛乳汁中的链球菌科、链球菌属的相对丰度增加,棒状杆菌科、罗尔斯通氏菌属、假单胞菌属的相对丰度下降。优势菌属中有4个嗜冷菌,健康奶牛和乳腺炎奶牛乳汁中的嗜冷菌总丰度分别为19.5%和42.0%。提示乳汁中微生物组成变化可能与奶牛乳腺炎的发生发展有密切联系,该研究为奶牛场乳房炎的防控及原料奶的质量控制提供了理论依据。

The occurrence of cow mastitis is related to a variety of pathogenic microorganisms.Analysizing the characteristics of milk flora is of great significance for establishing mastitis prevention and control system,as well as improving safety and quality of dairy products.This study analyzed the structural diversity and richness ofmicrobial communities in bovinemilk from 17 healthy cows and 10 mastitic cows inHenan Province by 16S rRNA sequencing with V3-V4 gene region.The results showed that there were significant differences in the relative abundance of microbial communities at the levels of 11 phyla,24 classes,37 orders,82 families,and 184 genera.The diversity and richness of microbial flora structure in the mastitis milk were significantly lower than that of healthy cows.Firmicutes,Proteobacteria and Actinobacteria are the phyla with higher relative abundance in milk of mastitis cows.After mastitis,the abundance of Proteobacteria and Tenericutes decreased significantly,the abundance of Synergistetes significantly increased.The relative abundance of Streptococcaceae and Streptococcus in the milk of mastitis cows increased,while the relative abundance of Corynebacteriaceae,Ralstonia and Pseudomonas decreased.There were four Psychrophilic bacteria in the dominant genera.The total abundance of Psychrophilic bacteria in the milk of healthy cows and mastitis cows was 19.5%and 42.0%,respectively.This study provides a theoretical basis for preventing and controlling mastitis in dairy farms,as well as controlling the quality of raw milk.