豫北地区猪源大肠杆菌耐药性及基因多态性分析

Analysis of drug resistance and genetic polymorphism of Escherichia coli isolated from pigs in north of Henan Province

关键词:  猪源大肠杆菌  药物敏感实验  耐药基因  RAPD技术

Key words:  Porcine Escherichia coli  Drug sensitivity test  Drug resistance gene  RAPD technology

摘要:

为了解豫北地区规模化养殖场猪源大肠杆菌的耐药性及基因多态性。本研究对分离的21株猪源大肠杆菌进行了药物敏感实验、采用PCR技术对其耐药基因进行了检测，同时用RAPD技术进行了基因多态性分析。结果表明：豫北地区规模化养殖场分离的猪源性大肠杆菌菌株对常见16种抗生素存在不同情况的耐药性、其中对四环素、红霉素、麦迪霉素、阿莫西林、磺胺异恶唑、环丙沙星、新生霉素、复方新诺明、恩诺沙星、甲氧苄啶的耐药率均为100%，对庆大霉素、洛美沙星的耐药率为85%以上，对其它药物的耐药率相对较低；PCR检测得到8种耐药基因的条带；对菌株进行RAPD分析得到7种不同的基因型；研究表明，大肠杆菌极易产生耐药性，耐药基因广泛存在于耐药菌株中，但耐药表型与耐药基因之间无绝对相关性。由此可见，豫北地区猪源大肠杆菌感染多重耐药十分严重，严重影响了该地区猪源大肠杆菌病的诊治和预防。

Abstract:

To determine the drug resistance and gene polymorphism of Escherichia coli isolated from pigs from north of Henan Province. In this study, 21 isolated porcine Escherichia coil were detected with drug sensitivity test, and the drug resistance genes were detected by PCR, the gene polymorphism was analyzed by RAPD. The results showed that the isolated Escherichia coli strains have different resistance to 16 common antibiotics, and the drug resistance rate of strains for Tetracycline, erythromycin, medemycin, amoxicillin, sulfamethoxazole, ciprofloxacin, neomycin, Sulfamethoxazole, enrofloxacin, trimethoprim were 100%, The drug resistance rate for gentamicin and lomefloxacin were more than 85%, and drug resistance rate for the remained antibiotics had the low resistance rate. At the same time, 8 drug resistance genes was obtained by PCR from the isolated strains; 7 different genotypes were obtained with the RAPD analysis. The above results showed that Porcine Escherichia coli was easy to form the resistance to drug, and resistance genes were widely existed in these resistant strains, but there was no correlation between resistant phenotype and resistant genes. This study revealed that Porcine Escherichia coli were multidrug resistance in north of Henan, would seriously affect diagnosis and treatment prevention of Porcine Escherichia coli.