撒坝猪大肠杆菌血清型鉴定及药敏试验与HPI irp2基因的检测

Serotype identification and drug susceptibility testing of Escherichia coli and the detection of the HPI irp2 gene in Saba pigs

为了对云南省楚雄和禄丰地区撒坝猪大肠杆菌血清型及药物敏感性与irp2基因的关系,试验采集疑似猪大肠杆菌病患猪的心脏、肝脏和粪便等病料,用于大肠杆菌的分离培养、形态学观察、生化鉴定,并进行了血清型鉴定与药敏试验和irp2基因的检测。结果表明:共鉴定出大肠杆菌50株,10种血清型,其中O20、0101、O14、O5、O9为优势血清型;头孢类、四环素类、氨基糖苷类和青霉素类这4种药中,以头孢类的头孢他啶作用最强;50株大肠杆菌中有12株(24%)扩增出434 bp的基因片段,其PCR产物测序结果与GenBank中公布的耶尔森菌强毒力岛(HPI)irp2基因的同源性达96%以上。说明irp2基因与血清型的致病性有关。

To investigate the relationships betwen the Escherichia coli serotypes and drug susceptibility with the irp2 gene in Saba pigs from Chuxiong and Lufeng areas of Yunnan Province. Some pathological materials from the pigs with suspected Escherichia coil infection, such as heart ,liver and faeces, ctc, were used for the isolation and culture, morphological observation and biochemical identification of Escherichia coll. And then the serotype identification, drug susceptibility testing, and detection of Irp2 gene were also carried out： The results showed that 50 strains and 10 serotypes of Escherichia coli were identified in total. The predominant serotypes were O201 O101 , O14, O5 , and O9 among ten kinds of serotypes. The drug susceptibility tesing showed that among four kinds of medicines including cephalosporins, tetracycline, aminoglyeoside and penicillin,which of the stonggest effect was eeftazidime of cephalosporins. The PCR results showed that the 434 bp gene fragments of the irp2 gene were amplified from 12 strains （24%） of Escherichia coli among the 50 strains, the sequencing results of PCR products shared a homology of more than 96% with the irp2 gene of Yersirtia HPI published in GenBank. The reaults indicate that the irp2 gene is related to pathogenicity of the 8erotypea.