某育肥羊场呼吸道疾病的诊断与病原学鉴定

Diagnosis and pathogen identification of the respiratory disease in a fattening goat farm

为明确江苏某羊场外购育肥羊突发呼吸道疾病的病因,本研究结合临床症状、剖检病变观察、病原学检测与分离鉴定等方法对病因进行分析。结果表明:该病是由肠道外致病性大肠杆菌、山羊副流感病毒3型及绵羊肺炎支原体混合感染所致。分离所得的2株大肠杆菌对多黏菌素B、强力霉素敏感,对其他12种常见抗生素均不敏感,检测到其携带有iss、fyuA、iroN、cvaC、fimH、iutA、kpsMTⅡ这7种毒力基因,分别属于系统进化群B1群与B2群。通过MDBK细胞成功分离获得1株山羊副流感病毒3型毒株,其M基因片段与流行毒株同源性最高达99.7%。该结果将有助于科学认识和防控山羊呼吸道疾病。

In order to clarify the etiology of the respiratory disease in a fattening goat farm in Jiangsu Province,observation of clinical symptoms and pathogenic lesions,pathogens detection,isolation and identification were performed on the affected goats.The results showed that the disease was caused by co-infection of extra-intestinal pathogenic Escherichia coli(ExPEC),caprine parainfluenza virus type 3(CPIV3)and Mycoplasma ovinepneumoniae(Mo).The two isolated ExPEC strains were sensitive to polymyxin B and doxycycline,but not to the other twelve common antibiotics.They were detected to carry seven virulence genes,including iss,fyuA,iroN,cvaC,fimH,iutA and kpsMTⅡ,belonging to phylogenetic groups B1 and B2,respectively.A CPIV3 strain was successfully isolated from the MDBK cells,and its M gene fragment was 99%homologous to the prevalent strains.These results would be helpful for scientific understanding and prevention ofrespiratory diseases in goats in the future.