牛冠状病毒、牛轮状病毒和致病性大肠杆菌混合感染致犊牛腹泻的研究

Study on Calf Diarrhea caused by mixed infection of Bovine Coronavirus, Bovine Rotavirus and Pathogenic Escherichia Coli

中文关键词: 犊牛腹泻  牛轮状病毒  牛冠状病毒  大肠杆菌  混合感染  

英文关键词: calf diarrhea  bovine rotavirus  bovine coronavirus  escherichia coli  mixed infection  

中文摘要:

      为了明确新疆石河子某规模化奶牛场犊牛腹泻病死率较高的原因。本研究对腹泻犊牛的粪样及病死犊牛肠道内容物进行病原检测，并对分离菌株进行毒力基因检测、耐药基因检测、动物致病性试验及药敏试验。最终明确病因主要由牛冠状病毒(BCoV)和牛轮状病毒(BRV)和大肠杆菌混合感染引起。药敏试验表明，分离到的大肠杆菌对28种抗生素产生了严重的耐药，仅对多粘菌素和呋喃妥因敏感，并且发现该菌同时携带2种毒力基因和10种耐药基因。本研究分离的一株大肠杆菌携带有丰富的耐药基因，具有多重耐药性，为该奶牛场上临床治疗加大了难度。而本试验结果为该养殖场提供科学的临床药物指导，为该牛场治疗此次犊牛腹泻提供了依据，同时为新疆犊牛腹泻混合感染的防控提供了病例参考和技术资料。

英文摘要:

      In order to clarify the reasons for the high mortality rate of calf diarrhea in a large-scale dairy farm in Shihezi, Xinjiang.In this study, the fecal samples of diarrhea calves and the intestinal contents of dead calves were detected, and the virulence gene detection, drug resistance gene detection, animal pathogenicity test and drug sensitivity test were performed on the isolated strains.The final cause was mainly caused by mixed infection of bovine coronavirus ( BCoV ) and bovine rotavirus ( BRV ) and Escherichia coli. The drug sensitivity test showed that the isolated E.coli was severely resistant to 28 antibiotics, and was only sensitive to polymyxin and nitrofurantoin. It was found that the bacteria carried 2 virulence genes and 10 drug resistance genes at the same time.A strain of Escherichia coli isolated in this study carried abundant drug resistance genes and had multiple drug resistance, which increased the difficulty of clinical treatment on the dairy farm. The results of this experiment provide scientific clinical drug guidance for the farm, provide a basis for the treatment of calf diarrhea in the farm, and provide case reference and technical data for the prevention and control of mixed infection of calf diarrhea in Xinjiang.