鸡源性多重耐药沙门菌质粒与耐药性相关性分析

Correlation Analysis of Plasmid and Drug Resistance of Multidrug-resistance Salmonella Isolated from Chickens

为了解鸡源性沙门菌临床分离株多重耐药情况与质粒的携带关系,采用K-B纸片法对13株鸡源沙门菌分离菌株进行10种抗菌药物敏感性试验,通过质粒图谱检测耐药菌株质粒携带情况,分析质粒图谱和耐药谱的关系,采用0.5%SDS和43°C对分离菌进行质粒消除,根据质粒消除前后耐药谱的变化,初步对耐药基因进行定位。13株分离菌均表现为多重耐药,大部分菌株为5重及以上耐药,最主要的多重耐药谱是AMP-CIP-OFL-NOR-SXT-TET,分离菌均检测到了质粒的存在。质粒消除后,耐药谱明显变窄,耐药菌株恢复了对大多数药物的敏感性。结果表明,鸡源性多重耐药沙门菌的耐药性与质粒的携带关系密切,初步推断编码四环素、环丙沙星、氧氟沙星和诺氟沙星的耐药基因主要存在于质粒上。

To investigate the relationship between multidrug resistance and plasmids in Salmonella isolated from chickens,the sensitivity tests of 13 isolates to 10 antibacterials were performed by Kirby-Bauer method and the carried plasmids were detected by plasmid profiles. Then the plasmids in the isolates were eliminated by high temperature（43 ℃）and 0.5% SDS,and the location of resistance gene was tested preliminary by the pair sensitivity tests before and after plasmids eliminated. The results suggested that all strains were resistant to more than two kinds of antibacterials,the most isolates were resistant to five or more kinds of antibacterials,and AMP-CIP-OFL-NOR-SXT-TET was the main multidrug-resistance spectrum;Plasmids were discovered in 13 isolates;The drug resistance spectrum was significantly narrowed and all isolates renewed the sensitivity to most of the drugs after plasmids eliminated.These results suggested that there was close relationship between multidrug resistance of Salmonella and plasmids,and resistance genes encoding tetracycline,ciprofloxacin,ofloxacin and norfloxacin were mainly in the plasmids.