规模化牛场犊牛直肠细菌多样性分析

Analysis of microbial diversity in rectum of calf in largescale cattle farm

摘要:

摘要:【目的】研究腹泻犊牛直肠细菌多样性，以及与健康犊牛直肠细菌多样性的差异。【方法】通过建立直肠菌群16S rRNA 基因克隆文库，分别用限制性内切酶MspⅠ和HhaⅠ对阳性克隆的PCR 产物进行限制性酶切片段长度多态性(RFLP)分析，通过测定16S rRNA 基因序列，绘制系统发育树，确定犊牛直肠菌群的组成。【结果】腹泻组克隆阳性率达98. 75% (474 /480)，优势菌群以乳杆菌属(14%)、肠球菌属(10%) 和埃希菌属(8%)等需氧和兼性厌氧菌为主，健康组克隆阳性率达96.45%(488/506)，优势菌群以梭菌属(13%)、双歧杆菌属(8%)和巨型球菌属(5%)等专性厌氧菌为主。【结论】2 周龄犊牛直肠菌群复杂多样，并且具有自己的独特性菌群，且腹泻时乳杆菌属、肠球菌属、埃希氏菌属等显著增加。

Abstract:

Abstract:［Objective］ To analyze the diversity of bacterial community in rectum of diarrheic calves，and differences with health calves．［Methods］16S rRNA clone libraries were constructed，positive clones were digested by Msp I and Hha I for restriction fragment length polymorphism (RFLP) ，and then a phylogenetic tree was depicted based on the 16S rRNA sequencing，to confirm the compose of microbe in the diarrheic calf rectum．［Results］ The positive rate of clone was 98. 75% (474/480) in diarrheic calves，the dominant bacteria included Lactobacillus (14%)，Enterococcus (10%) and Escherichia (8%)． The positive rate of clone was 96. 45% (488/506) in health samples，the dominant bacteria included Clostridium (13%)，Bifidobacterium (8%)，Megasphaera (5%)．［Conclusion］Complexity and diversity of bacterial community in rectum in 2 weeks old calves had their own features，and significant increase of Lactobacillus，Enterococcus and Escherichia was found in diarrhea calves．