1株猪丹毒杆菌的分离与鉴定

Isolation and identification of one Erysipelothrix rhusiopathiae field strain

为确定导致安徽和县某猪场猪只发病的病原,从该猪场送检病料(心、肺、脾、肝)中分离并纯化细菌,根据其形态特征、PCR鉴定及生化试验结果,确诊为猪丹毒杆菌。spa A基因序列分析结果显示该菌与猪丹毒杆菌G4T10(Gen Bank登录号:KF150604.1)有99%的同源性。全自动生化反应报告该菌为丹毒丝菌的概率高达95%。小鼠攻毒试验表明,试验组小鼠在腹股沟皮下注射该菌后,4 d内全部死亡;死亡小鼠剖检可见全身败血性出血,各脏器均有病变,从死亡小鼠的血液、心、肝、脾、肺等组织中分离到与该感染菌株形态特征完全一致的细菌。药敏试验结果表明,该菌对β-内酰胺类和大环内酯类抗生素敏感,对链霉素、卡那霉素、四环素、多西环素、林可霉素和磺胺异恶唑耐受。

One bacterial strain isolated from an acute case of swine erysipelas in Hexian of Anhui Province was identified as E-. rhusiopathiae by polymerase chain reaction（ PCR） and biochemical test. Sequence analysis of the hypervariable region in spa A gene showed99% identity with E. rhusiopathiae strain G4T10（ Genbank accession number： KF150604. 1）. The newly isolated strain has a 95% probability to be E. rhusiopathiae based on automatic biochemical test. The artificial infection of mice resulted in 100% mortality. The bacterial strain was highly sensitive to β-lactam antibiotics and macrolides but resistant to streptomycin,kanamycin,tetracycline,doxycycline,lincomycin and sulfisoxazole.