El Hussein H A, Hamid M E
Department of Medicine, Faculty of Veterinary Science, University of Khartoum, Khartoum North, Sudan.
Trop Anim Health Prod. 2009 Apr;41(4):617-22. doi: 10.1007/s11250-008-9232-4. Epub 2008 Sep 30.
Mycobacterium farcinogenes is the causal agent of bovine farcy, a chronic infectious disease of zebu cattle in some parts of tropical Africa. Whole cell homologous antigen of M. farcinogenes was used in the standardization and evaluation of an enzyme linked immunosorbent assay (ELISA) for the detection of circulating antibodies against bovine farcy using sera from confirmed bovine farcy and from bovine farcy-free cattle. The cut-off optical density (OD) value was decided at 1.8 using filter 405 nm after one hour of incubation at 37 degrees C. Accordingly, 115 out of 124 (92.7%) serum samples from clinically proven bovine farcy cattle were reported sero-positive. Sera from cattle infected with M. avium and M. paratuberculosis revealed OD value <1.8, indicating the differential diagnostic ability of M. farcinogenes antigen. Our test sensitivity was 92.7% and specificity was 97%, therefore could be routinely employed to support early clinical diagnosis, epidemiological surveys and for screening animals before exportation to farcy-free regions.
伪结核分枝杆菌是牛皮肤鼻疽的病原体,牛皮肤鼻疽是热带非洲部分地区瘤牛的一种慢性传染病。利用伪结核分枝杆菌的全细胞同源抗原,以确诊患有牛皮肤鼻疽的牛和未患牛皮肤鼻疽的牛的血清为样本,对用于检测牛皮肤鼻疽循环抗体的酶联免疫吸附测定(ELISA)进行标准化和评估。在37℃孵育1小时后,使用405nm滤光片测定临界光密度(OD)值为1.8。因此,124份经临床证实患有牛皮肤鼻疽的牛的血清样本中有115份(92.7%)报告为血清阳性。感染鸟分枝杆菌和副结核分枝杆菌的牛的血清OD值<1.8,表明伪结核分枝杆菌抗原具有鉴别诊断能力。我们的检测灵敏度为92.7%,特异性为97%,因此可常规用于支持早期临床诊断、流行病学调查以及在动物出口到无皮肤鼻疽地区之前进行筛查。