伪结核棒状杆菌试验感染家兔的临床与病理学变化

Clinical and pathological changes of rabbits experimentally infected with Corynebacterium pseudotuberculosis

为了系统掌握伪结核棒状杆菌人工感染实验动物后的发病情况、临床特征及主要病理学变化,为实验室诊断提供科学的基础数据,利用伪结核棒状杆菌标准强毒株ATCC19410按不同剂量感染3只家兔,观察其临床及病理学变化,从病料中分离病原菌,对其形态及培养特性进行观察。结果显示,家兔接种15d后,接种部位皮肤开始肿胀,随着时间的延长,肿块表面皮肤开始破溃,有白色而黏稠的脓汁排出,排脓后破溃创口逐渐结痂愈合,无其他明显临床症状;剖检可见肝、胃部大网膜有白色散在的化脓灶,两侧腋浅前淋巴结肿大,切开后有干酪样脓汁;病理组织学观察可见,皮肤感染局部病灶由典型的中央坏死区和周围纤维素性肉芽肿组成,其他各主要脏器组织均有充血、出血等现象;从病料中成功分离到了病原菌,镜下形态及培养特性均与感染所用标准毒株一致。结果表明,家兔人工感染伪结核棒状杆菌后主要形成局灶性脓肿,并有特征性的具有诊断意义的组织学病理变化。

In order to systematically study the incidence of laboratory animals experimentally infected with Corynebacterium pseudotuberculosis and provide scientific data for diagnosis of pseudotuberculosis, three rabbits were infected using different doses of standard virulent strain ATCC 19410 of C. pseudotuber- culosis. The clinical symptoms and pathological changes were observed. The pathogen was isolated from the tissues, and the morphological and cultural characteristics of the pathogen were studied. The results showed that 15 days after the inoculation,the inoculation site began to swelled. With prolongation of the disease, the surface skin of the swelled sites began to ulcer with the discharge of white and sticky pus,then the ul- cerated wound gradually healed after the discharge of pus. No other obvious clinical symptoms were ob- served. Necropsy showed that white purulent foci scattered on the liver and omentum of stomach, enlarge- ment of axillary lymph nodes with caseous pus from incision was observed. Histopathology observation showed that local foci of infectious skin composed of central necrotic area and surrounding cellulose granu- loma. Hyperemia and hemorrhage were seen in many other major tissues. The isolated pathogen was con- sistent with the standard strain. The results indicated that the rabbit experimentally infected with C. pseudotuberculosis mainly causes focal abscess, and these abscess and some characteristic histologicalchanges may be useful for diagnosis.