贵州省猪源沙门氏菌Ⅰ类整合子与耐药基因盒研究

摘要

To investigate the prevalence state of classⅠintegron in Salmonella, the carrying rates of classⅠintegrons and the types of drug resistance gene cassettes of 57 Salmonella strains isolated from scale swine farms were determined by polymerase chain reaction ( PCR) .The susceptibility of the Salmonella strains to 12 antimicrobial was tested by the broth dilution method.The correlation of anti-microbial resistance between the positive and negative strains of classⅠintegron was analyzed byχ2 test.The results showed that the carry-ing rate of classⅠintegrons and drug resistance gene cassettes was 40.4%(23/57) and 31.6%(18/57) re-spectively.The genes of aadA2, aadA5, aadA22, aadA23b, dfrA1, dfrA12 and dfrA17 were checked out in classⅠintegrons, which mediated Salmonella resistance to aminoglycoside antibiotics and sulfa drug resistance respectively.Fifty seven strains of Salmonella had different drug resistance rates to 12 antimicrobial.The gene cassette carried in classⅠintegron presented obvious relativity to multi-drug-resistance ( MDR) .%为了调查规模养殖场沙门氏菌中Ⅰ类整合子的流行情况，采用聚合酶链式反应检测了从贵州省规模养猪场分离的57株沙门氏菌中Ⅰ类整合子的携带率以及整合子中耐药基因盒的种类；采用微量肉汤稀释法测定了57株沙门氏菌对12种抗菌药物的敏感性；并应用χ2检验检测Ⅰ类整合子阳性菌株与阴性菌株耐药性的相关性。结果显示，57株沙门氏菌中Ⅰ类整合子检出率为40．4％（23／57）；耐药基因盒检出率为31．6％（18／57）；整合子中携带可分别介导对氨基糖苷类和磺胺类药物耐药的 aadA2、aadA5、aadA22、aa－dA23b、dfrA1、dfrA12和dfrA17基因；57株沙门氏菌对12种抗菌药物的耐药率不同，Ⅰ类整合子与多重耐药之间有明显的相关性。