对广东地区分离的副猪嗜血杆菌进行耐药性调查以及遗传相关性分析,以获得临床分离株的耐药性特征和耐药菌的传播扩散机制。采用微量肉汤稀释法测定了95株副猪嗜血杆菌对临床常用的18种抗菌药物的敏感性。用PC R方法检测6类抗生素耐药基因的携带情况,并运用脉冲场凝胶电泳(PFG E)对携带相关耐药基因的菌株进行遗传相关性分析。结果表明,所有测试菌株对头孢噻呋和头孢噻肟均表现出较好的敏感性;对左氧氟沙星、红霉素、氟苯尼考和青霉素敏感性下降,耐药率分别为3.2%、5.3%、7.4%和13.7%。同时也检测到较高的耐药水平,对甲氧苄啶+磺胺甲噁唑、恩诺沙星和头孢克洛的耐药率分别为83.2%、46.3%和36.8%;对四环素(23.2%)、氨苄西林(22.1%)、庆大霉素(21.1%)和环丙沙星(20.0%)表现为中等水平的耐药。在95株菌中,26株菌(27.4%)携带有耐药基因,共检出5种耐药基因,检出率依次为tet(B)(21.1%)、aph(3′)-Ⅰ(9.5%)、sul2(9.5%)、aad A 1(8.4%)和blaROB-1(6.3%),其中15株菌同时携带有2个以上的耐药基因。在这些耐药基因阳性菌中,PFGE分析结果显示出遗传背景的多样性,同时,也观察到小范围的克隆。 To investigate the drug resistance of Haemophilus parasuis separated in Guangdong Province and the genetic correlation analysis to obtain the drug resistance characteristics of clinical isolates and the spread mechanism of drug-resistant bacteria. The sensitivity of 95 strains of Haemophilus parasuis to 18 kinds of antibacterials commonly used in clinic was determined by the broth microdilution method. The PC R method was used to detect the resistance of six kinds of antibiotic resistance genes. The genetic correlation analysis of the strains carrying the related resistance genes was carried out by using pulsed-field gel electrophoresis (PFG E). The results showed that all the tested strains showed good sensitivity to ceftiofur and cefotaxime, the sensitivity to levofloxacin, erythromycin, florfenicol and penicillin was decreased, and the resistance rates were 3.2%, 5.3% , 7.4% and 13.7% respectively. The resistance rates to trimethoprim + sulfamethoxazole, enrofloxacin and cefaclor were 83.2%, 46.3% and 36.8%, respectively. For tetracycline (23.2% ), Ampicillin (22.1%), gentamicin (21.1%) and ciprofloxacin (20.0%) showed moderate levels of resistance. Among 95 strains of bacteria, 26 strains (27.4%) had drug resistance genes, and 5 resistant genes were detected. The detection rates were tet (B) (21.1%), aph 9.5%, sul2 (9.5%), aad A 1 (8.4%) and blaROB-1 (6.3%), of which 15 strains harbor more than two resistance genes at the same time. In these drug-resistant gene-positive bacteria, PFGE analysis showed a diversity of genetic backgrounds, while small clones were also observed.