某规模化奶牛场牛肺外结核的病理学诊断

Pathological diagnosis of bovine extrapulmonary tuberculosis in a dairy cattle farm

验证牛结核菌素阳性反应牛的结核病变及其病变的组织分布及病变特征,追踪感染源及传播途径,为奶牛场结核检疫净化提供技术支持。在新疆某规模化奶牛场应用牛结核菌素皮内变态反应(SIT)、IFN-γ试验、PPD点眼反应、ELISA抗体检测4种方法联合检疫,综合判定感染牛23头,全部扑杀并进行系统剖检,采集病料,进行病理组织学和细菌学诊断。剖检结果表明,23头牛中14头牛在肝、脾、淋巴结等肺外组织器官发现眼观结核病变而未见肺脏结核病变,仅有2头发现肺脏及肺门淋巴结病变,7头牛在全身组织器官未能发现眼观结核病变;病理组织学检查结果表明,剖检的23头牛均呈现早、中、后期典型结核结节病变,11头牛的病料分离培养到牛分枝杆菌。该奶牛场结核主要表现为肺外结核,经典肺结核较少,这可能是该奶牛场在以往扑杀的阳性牛中很少发现肺脏结核病变的原因。

To trace the source and routes of transmission, and provide technical support for the quarantine and purification of cattle farms,the distribution and characteristics of tuberculosis le sions were tested and verified in positive cattle tested by PPD intradermal allergy. Four methods including SIT,Gamma-interferon assay（IFN-γ）,eye drops reaction（PPD） and enzyme linked immuno sorbent assay（ELISA） were used to detect the bovine tuberculosis in dairy farm in Xinjiang. 23 cattle with advanced infection were slaughtered and necropsied systematically. Meanwhile, the diseased materials were collected to perform histopathological and bacteriological diagnosis. There were 14 cattle with macroscopical lesions in livers,spleens or lymph nodes instead of in lungs and only 2 cattle with maeroscopical lesions in lungs and hilar lymph nodes,7 cattle without any mac- roscopical lesions in all tissues and organs. Histopathological examination showed that the 23 cattle presented early,middle and advanced typical tubercular nodules,in which 11 cattle were isolated and cultured to Mycobacterium bovis. The bovine tuberculosis of this dairy farm mainly showed extrapulmanory tuberculosis instead of pulmonary tuberculosis. Maybe this is the reason why some cattle with positive diagnosis results did not displayed any lesions in lungs.