【摘要】 用2000~2003年自兽医临床分离的393株大肠杆菌,对9种常用抗生素的敏感性进行了检测。依据菌株采集时间、菌株来源对菌株耐药性的变化及耐药性产生之间的相关性进行了较全面的统计分析,并随机选出39株典型的多重耐药菌株观察了对小鼠的致病性。结果显示,393株分离菌对四环素、庆大霉素、氯霉素、氨苄青霉素、利福平、卡那霉素、呋喃妥因、链霉素和环丙沙星的耐药率分别为93.89%,57.76%,78.63%,77.86%,92.11%,47.33%,46.82%,76.84%,74.81%;按照耐药种类可将分离菌株分为8类,最多耐药9种,最少耐药2种,约80%以上的菌株耐受7种所试药物。猪源大肠杆菌对庆大霉素、氨苄青霉素、卡那霉素的耐药率高,而鸡源大肠杆菌对四环素、氯霉素、链霉素和环丙沙星的耐药率显著高于猪源大肠杆菌。2000年和2003年分离菌株的耐药率相比,氯霉素从67.33%上升到90.58%,氨苄青霉素从71.29%上升到84.81%,链霉素从73.76%上升到80.10%,环丙沙星从61.88%上升到88.48%,庆大霉素却从61.39%下降到53.92%。95%的菌株(37/39)可直接在72 h内致死感染小鼠(2.0×107CFU.鼠-1)。5%不能直接致死小鼠的菌株经小鼠体内2~3次传代,可直接致死感染小鼠。试验表明,兽医临床分离菌株普遍存在多重耐药性,并随分离时间、寄主种类等耐药率出现动态变化,耐药类型间具有一定的相关性。耐药菌株对小鼠仍具有很强的致病性,少数菌株致病性出现暂时减弱,但在体内几次传代即可恢复。更多还原

【Abstract】 The susceptibility to 9 kinds of antibiotics of 393 animal pathogenic E.coli isolated from clinical samples was de-termined from 2000 to 2003.The resistance to TC,GM,CMP,AMP,RA,KM,FT,SM and CIP were 93.89%,57.76%,78.63%,77.86%,92.11%,47.33%,46.82%,76.84% and 74.81%,respectively.The isolates could be classified into eightclasses according to the number of drugs to which srains were resistant.The resistance spectrum of the isolates varied from 2to 9 kinds of the above drugs.The strains that were resistant to seven kinds of drugs were more than 80 percent.The resis-tance rates of swine origin strains to GM,AMP and KM were higher than those of poultry origin strains,while the resistancerates of poultry origin strains to TC,CMP,SM and CIP were higher remarkably than those of swine origins.The frequency ofresistance increased from 2000 to 2003,which was from 67.33% to 90.58% for CMP,71.29% to 84.81% for AMP,73.76%to 80.10% for SM and 61.88% to 88.48% for CIP.At the same time,the resistance rate of GM decreased from 61.39% to53.92%.Thirty-seven strains(95 %) could make all the Kunming mice die within 72 h injected intraperitoneally with the cul-tures(1.0×108CFU.0.2 mL-1.mouse-1) of E.coli strains respectively.The others could restore virulence after passages ofmice three times in vivo.The pathogenicity of wild strains with drug resistance acquired naturaly to mice did not decline.更多还原