猪场副猪嗜血杆菌的分离鉴定及药敏试验

Isolation and Identification of Haemophilus parasuis and Drug Sensitive Test Isolates from Pathological Piglets

为查明贵阳市花溪区麦坪镇某猪场仔猪发生呼吸道疾病的病因,对送检的2头病猪采集病料进行细菌分离培养、染色镜检、生化试验、PCR扩增及测序、药敏试验。结果:从病料样本中分离得到1株细菌,根据形态学和生化试验初步鉴定为副猪嗜血杆菌;应用细菌16S rRNA序列分析技术从分子水平对分离细菌进行分型鉴定,运用DNAStar软件与不同血清型副猪嗜血杆菌基因序列进行比对,发现分离菌与不同血清型副猪嗜血杆菌菌株16S rRNA序列同源且相似性为97.4%～100%,其中与血清5型相似性最高;系统进化分析显示,分离菌株与血清5型副猪嗜血杆菌进化关系最近;分离菌株对利福平、头孢氨苄、阿米卡星、环丙沙星、万古霉素敏感。结论:综合分离细菌传统鉴定方法和分子生物学鉴定方法的实验结果,确定分离菌株属于血清5型副猪嗜血杆菌。

In oder to explore the causes of respiratory diseases of piglets of pig farm, in Maiping, Huaxi district of Guizhou province. Bacterial isolation and culture, staining and microscopic examination, biochemical test, PCR amplification and sequencing, and drug sensitivity test were performed on two sick pigs. Result:one strain suspected Haemophilus parasuis was isolated by traditional culture methods, identified as Haemophilus parasuis preliminarily according to the morphological and biochemical tests. The bacterial 16S rRNA sequence analysis technology was applied to classify and identify the isolated bacteria at the molecular level. DNAStar software was used to compare the Haemophilus parasuis 16S rRNA sequences of different serotypes strains, and it was found that its similarity of isolate strain and different serotypes with the published were 97.4%-100%,with the highest similarity with serotype 5. The phylogenetic tree analysis of 16S rRNA sequences indicated that isolate strain was clustered into one branch with serum type 5. Drug sensitivity test showed that Haemophilus parasuis isolates in this field were sensitive to rifampicin, ceftriaxin, amikacin, ciprofloxacin and vancomycin. Conclusion:the isolation was serum type 5 Haemophilus parasuis by combining the traditional identification methods and molecular biological identification methods.