摘要
为了解四川地区猪源致病性大肠埃希菌分子流行特点及流行趋势,本研究在2016—2018年,从四川省各个地区无菌采集患病猪肝脏、脾脏、肺脏、肠道等组织样品208份。通过细菌分离鉴定方法筛选出87株大肠埃希菌,通过小鼠攻毒试验确定其中22株为致病性大肠埃希菌,并对其进行分子分群、生物被膜形成能力检测、耐药性试验、耐药基因及HPI毒力基因检测。结果显示,22株致病性大肠埃希菌多分布于A群(59.09%),且生物被膜形成阳性率为72.73%,其中强成膜能力菌株占40.91%。大肠埃希菌对19种抗生素药物均有不同程度的耐药性,其中对恩诺沙星、复方新诺明、氨苄西林、阿莫西林、红霉素、四环素等9种药物的耐药率较高,为81.82%~100%;对庆大霉素、左氧氟沙星、诺氟沙星、头孢曲松等4种药物的耐药率为63.64%~72.73%;对其他药物的耐药率为4.55%~54.55%,均呈现多重耐药。22株致病性大肠埃希菌检出的耐药基因包括β-内酰胺类TEM(36.36%)、SHV(9.09%)、OXA(9.09%),磺胺类sulⅠ(63.64%)、sulⅡ(95.45%),氨基糖苷类acc(3)-Ⅱ(68.18%)、aph(3′)-Ⅱ(50.00%),氯霉素类cmlA(45.45%)、floR(81.82%),四环素类tetA(81.82%)、tetB(86.36%),喹诺酮类qurB(40.91%)共12个基因型,检测出HPI毒力基因irp1(40.91%)、irp2(13.64%)、fyuA(13.64%)3种。研究结果表明,四川省猪源致病性大肠埃希菌多分布于A群,生物被膜形成阳性率较高,存在严重的多重耐药性,四环素类、氯霉素类、氨基糖苷类及磺胺类耐药基因的携带率较高,且存在多重耐药基因与毒力基因共存情况。研究结果可为四川地区猪病的预防和治疗提供参考依据。
The experiment was to study the molecular characteristics and epidemic trends of pathogenic Escherichia coli from pigs in Sichuan Province.From2016 to2018,208 samples of liver,spleen,lung,and intestines of sick pigs were collected from various parts of Sichuan Province.87 strains of Escherichia coli were screened by bacterial isolation and identification methods,and22 strains of pathogenic Escherichia coli were determined by SPF mouse challenge test. Molecular grouping,biofilm formation ability detection, pathogenicity and drug resistance of the isolates were studied, drug resistance genes and three HPI virulence genes of pathogenic Escherichia coli were detected by PCR.The results showed that22 pathogenic Escherichia coli were distributed in group A (59.09%),the positive rate of biofilm formation was 72.73%,and the strong film-forming ability strain accounted for 40.91%.There are different degrees of resistance to19 antibiotics,among which nine drugs such as enrofloxacin, compound sulfamethoxazole,ampicillin,amoxicillin, erythromycin and tetracycline had higher resistance rates (81.82%-100%).The resistance rates of gentamicin, levofloxacin,norfloxacin and ceftriaxone were between 63.64% and 72.73%.The resistance rate to other drugs was between 4.55% and 54.55%,and all of the22 isolates were multi-drug resistant.Twelve drug resistance genes detected by22 pathogenic Escherichia coli include β-lactam TEM (36.36%), SHV (9.09%),OXA (9.09%),sulfonamide sul Ⅰ(63.64%), sul Ⅱ(95.45%),aminoglycosides acc (3)-Ⅱ(68.18%), aph (3′)-Ⅱ(50.00%),chloramphenicol cmlA (45.45%), floR (81.82%),tetracycline tetA (81.82%),tetB (86.36%),quinolone qurB (40.91%).Three HPI virulence genes irp1 ( 40.91%),irp2 (13.64%),and fyuA (13.64%) were detected. It indicated that the pathogenic Escherichia coli from pigs in Sichuan Province was mostly distributed in group A,the positive rate of biofilm formation was high and there was serious multi-drug resistance.The carrying rate of tetracyclines,chloramphenicols,aminoglycosides and sulfonamide-resistant genes were high,and there were multiple drug resistance genes and virulence genes coexisting.The results can provide reference for the prevention and treatment of pig colibacillosis in Sichuan Province.
作者
彭珂楠
周雪珂
殷鑫欢
李飞
蔡瑶
曾喻兵
江朝源
张儒博
杨泽晓
徐志文
朱玲
PENG Kenan;ZHOU Xueke;YIN Xinhuan;LI fei;CAI Yao;ZENG Yubing;JIANG Chaoyuan;ZHANG Rubo;YANG Zexiao;XU Zhiwen;ZHU Ling(College of Veterinary Medicine,Sichuan Agricultural University,Chengdu 611130,China;College of Life Sciences,Sichuan University,Chengdu 610044,China;KeyLaboratory of Animal Disease and Human Health of Sichuan Province,Sichuan Agricultural University,Chengdu 611130,China)
出处
《浙江农业学报》
CSCD
北大核心
2019年第10期1599-1607,共9页
Acta Agriculturae Zhejiangensis
基金
“十三五”国家重点研发计划项目(2018YFD0501102)
四川省科技支撑计划项目(2015NZ0072)
