一株奶山羊伪结核棒状杆菌的分离与鉴定

Isolation and Identification of Corynebacterium pseudotuberculosis from Goats

为获得陕西某羊场病羊脓包中的病原菌,以无菌采集的病羊颈部脓汁为材料,进行细菌分离培养,鉴定分离菌株的形态特征、培养特性、生化特性,挑取分离菌株进行协同溶血试验(cAMP)和16SrRNA基因的PCR扩增,并对序列进行分析,NJ法构建系统发育树;用分离菌株分别接种Balb/c小鼠和奶山羊;药敏试验鉴定分离株的耐药性。结果显示,分离菌株的形态特征、培养特性、生化特性与伯杰细菌鉴定手册所述伪结核棒状杆菌特性一致;测序显示分离菌株与GenBank中已收录伪结核棒状杆菌相似性达97%以上;Balb/c小鼠致病性试验和奶山羊动物回归试验表明分离株有强致病性;药敏试验表明分离菌株对红霉素、环丙沙星、克拉霉素、强力霉素、四环素、头孢唑啉、新霉素、氧氟沙星等多种抗生素敏感,对复方新诺明耐药。

In order to search for the pathogenic bacteria of the abscess from a caprine farm in Shaanxi prov ince,abscess from the infected goats was obtained sterilely for routine bacterial isolation and identification. The pathogen was identified as Corynebacterium pseudotuberculosis based on its morphology, culture characteristics,biochemical characteristics and synergistic hemolytic test. 16S rRNA gene PCR results and sequence alignments indicated that 16S rRNA gene from the isolate shared 97% identity with the Corynebacterium pseudotuberculosis in GenBank. Animal pathogenicity experiment in Balb/c mice and goats confirmed that the isolate was strongly pathogenic.The result of antimicrobial susceptibility test indicated that the strain was highly sensitive to erythromycin, ciprofloxacin, clarithromycin, doxycycline, tetracycline, cefazolin, neomycin and ofloxacin, but resistant to sulfamethoxazole.The results could provide a certain basis for prevention and treatment of the disease in the farm.