摘要
为了解鸡源致病性大肠埃希菌对氨基糖苷类抗生素的耐药性变化和钝化酶耐药基因的携带情况及耐药基因与耐药性的相关性,从陕西、河南、河北、山西、宁夏和甘肃6省(区)的部分规模化养鸡场的病、死鸡中分离鉴定320株致病性大肠埃希菌。采用K-B药敏纸片法检测分离菌对6种氨基糖苷类药物的敏感性,PCR方法检测6种氨基糖苷类钝化酶耐药基因,用DNA Star软件对获得的耐药基因序列与GenBank中的相关序列进行比对。结果显示,鸡源致病性大肠埃希菌分离株对庆大霉素、链霉素、妥布霉素、卡那霉素、新霉素和阿米卡星的耐药率分别为53.4%、49.3%、37.5%、34.7%、22.8%和5.3%,对妥布霉素和卡那霉素耐药率呈上升趋势,而对庆大霉素的耐药率虽呈下降趋势,但仍维持在40%以上。3重以上耐药菌株占80%(256/320)。氨基糖苷类钝化酶基因aac(3)-Ⅱ、aph(3′)-Ⅰ和aac(6′)-Ⅰ的检出率分别为50.9%、25.9%和3.1%,未检测到aac(3)-Ⅳ、ant(3′′)-Ⅰ和aph(3′)-Ⅱ基因。研究表明,分离的鸡源致病性大肠埃希菌对氨基糖苷类抗生素的耐药性普遍存在,以多重耐药为主,且对妥布霉素和卡那霉素的耐药性不断上升。耐药基因aac(3)-Ⅱ和aph(3′)-Ⅰ的检出率与其耐药性呈正相关。
In order to know the trend of the aminoglycoside resistance and modifying enzyme resistance genes and the correlation between resistance genes and antimicrobial resistance of pathogenic Escherichia coli from chickens, a total of 320 pathogenic E. coli isolates were derived from clinically infected chicken of scale chicken farms in Shaanxi, Henan, Hebei,Shanxi,Ningxia and Gansu provinces during 1992-2011. Antimicrobial susceptibility of 320 pathogenic E. coli isolates against 6 aminoglycoside agents was deter- mined by the Kirby-Bauer disk diffusion method and 6 aminoglycoside modifying enzyme genes were identi- fied by using PCR. The resistance gene sequence alignment with the sequence in GenBank database were performed by using DNA Star. The results indicated that the resistant rates of E. coli isolates to gentami- cin streptomycin, tobramycin, kanamycin, neomycin and amikacin were 53.4% 49.3%, 37. 5%, 34. 7 %, 22.8% and 5. 3%, respectively, and the resistance rates to tobramycin and kanamycin had a increasing trend, while the resistance rate to gentamicin had a decreasing trend, but was consistently over 40%. The isolates resistant to more than 3 kinds of antimicrobials accounted for 80% （256/320）. The detection rates of resistance gene aac（3）- Ⅱ,aph（3＇）- I and aac（6＇）- I were 50.9% ,25.9% and 3.1%, respectively. The results revealed that the resistance to aminoglycosides of pathogenic E. coli from chickens was widespread, and was priority to multidrug resistance,while the resistance to tobramycin and kanamycin was increasing. The detection rates of aac（3）-Ⅱ and aph（3P）- I genes were positively associated with their resistance to aminoglycosides.
出处
《动物医学进展》
CSCD
北大核心
2012年第7期49-53,共5页
Progress In Veterinary Medicine
基金
陕西省科技统筹创新工程计划项目(2011KTDZ02-01)
关键词
大肠埃希菌
氨基糖苷类钝化酶基因
耐药性
鸡
Escherichia coli
aminoglycosid
modifying enzyme genes
antimicrobial resistance
chicken
