Isolation and identification of Haemophilus parasuis and tbpA gene | 陕西省副猪嗜血杆菌的分离及其基于tbpA基因的分型鉴定

Chinese. 检测副猪嗜血杆菌(Haemophilus parasuis, Hps)在陕西关中地区的感染状况，并对分离菌株进行基因型分析，为该地区副猪嗜血杆菌病的流行病学研究提供依据。从陕西关中地区14个发生多发性关节炎和浆膜炎的猪场采集30份病料，分离细菌，通过其培养特性和形态观察及生化试验和PCR等方法对分离株进行鉴定，并用Blast软件对分离株的16S rRNA序列进行同源性比对，同时对分离菌株进行了几种常见药物的敏感性检测。通过3种限制性内切酶TaqⅠ、AvaⅠ、AfaⅠ，对已被鉴定为副猪嗜血杆菌菌株的转铁结合蛋白A编码基因(tbpA）进行PCR-RFLP基因分型。分离得到了5株疑似副猪嗜血杆菌菌株，经培养特性和形态观察、生化试验、PCR鉴定及序列同源性比对，将其鉴定为副猪嗜血杆菌。PCR-RFLP分型结果表明，从5株副猪嗜血杆菌分离株中共得到了4种基因型，分别为EBC、BBJ、EBJ、EAD。药物敏感性检测结果表明，分离菌株的耐药性均较强，且不同分离株对同一药物敏感性不同。副猪嗜血杆菌病在陕西关中地区猪群中流行比较严重，其基因型较多且与其他地域的菌株有一定差异。

English. The study was to detect Haemophilus parasuis in swine herds in Guanzhong District in Shaanxi Province and type the tbpA gene by PCR-RFLP, providing references for the study of epidemiology of H. parasuis. From 30 samples of 14 pig farms in Guanzhong District of Shaanxi province, we isolated bacteria from the swine which were characterized by polyserositis and fibrinopurulent polyarthritis and identified them based on the cultural characteristics, morphologic characteristics, biochemical characteristics, PCR test and the sequence analysis through the Blast software. Meanwhile, the isolates were subjected to the drug sensitive tests for some common drugs and then were analyzed using PCR-RFLP based on the tbpA gene using TaqⅠ, AvaⅠ and AfaⅠendonucleases. We isolated and identified 5 H. parasuis isolates through the cultural characteristics, morphologic characteristics, biochemical characteristics, PCR test and the sequence analysis. And through the analysis of the 1 900 bp tbpA amplification using TaqⅠ, AvaⅠ and AfaⅠendonucleases we obtained 4 genotyping patterns, naming them EBC, BBJ, EBJ, EAD, respectively. The drug sensitive tests results showed that the five isolates were not sensitive to the common drugs and the sensitivity of the isolates to the same drug differed from each other. The results confirmed that the Gl-sser’s disease existed in Guanzhong District in Shaanxi Province with numerous genotypes which differed from each other according to their different regions.