两奶牛场布氏杆菌分离鉴定及四种血清学检测方法比较

Isolation and identification of Brucella in two dairies and comparison of four serological tests

目的与方法用虎红平板凝集试验(RBT)、试管凝集试验(SAT)、间接酶联免疫吸附试验(iELISA)和竞争酶联免疫吸附试验(cELISA)4种血清学检测方法对华东区和新疆的两奶牛场的600头奶牛进行了布氏杆菌病检测,采集布氏杆菌病血清学检测为阳性的奶牛的奶样120份,进行病原分离与鉴定。结果分离到细菌17株,经革兰氏染色、柯兹罗夫斯基鉴别染色和PCR鉴定,17株分离菌株均为牛种布氏杆菌;4种血清学检测结果RBT平均阳性率为46.33%,SAT平均阳性率为41.00%,iELISA平均阳性率为48.17%,cELISA平均阳性率为40.50%。结论两奶牛场平均分菌率为14.17%,按国标标准方法SAT检疫血清阳性率为41.00%,RBT的敏感性和特异性为86.36%和85.71%,SAT的敏感性和特异性为84.09%和92.06%,iELISA的敏感性和特异性为86.36%和96.83%,cELISA的敏感性和特异性为95.45%和98.41%。iELISA和cELISA在敏感性和特异性方面均高于RBT和SAT。iELISA和cELISA可作为RBT和SAT的替代方法。

Four kinds of serological tests, i.e. rose bengal plane test （RBT）, standard agglutination test （SAT）, indirect enzyme linked immunosorbent assay （iELISA） and competitive enzyme linked immunosorbent assay （cELISA） were used to detect the presence of Brucella in 600 dairy milk cows from two dairies in east China and Xinjiang area. And 120 milk sam ples taken from the dairy milk cows with positive serological reactions to Brucella infection were selected to perform the isolation of the etiological agents and their identification by means of Gram and Kozlowski staining as well as PCR assay. With these methods of testing, 17 strains of Brucella abortus were isolated in these two dairies with an average positive rate of 14.17%, while the average positive rates of the 4 serological tests, RBT, SAT, iELISA and cELISA were 46.33%, 41.00%, 48.17% and 40.50% respectively. Meanwhile, the sensitivities and specifieities of RBT, SAT, iELISA and cELISA tests were 86.36 % and 85.71%, 84.09% and 92. 06%, 86.36% and 96.83%, 95.45% and 98.41% respectively. It is evident that the sensitivities and specificities of iELISA and cELISA are higher than those of RBT and SAT test , and these two methods can be used as alterative method of testing for Brucella in cow milk to replace the RBT and SAT tests usually used in the detection of Brucella.