1株致禽霍乱多杀性巴氏杆菌的病原学与分子生物学鉴定

Identification of Pasteurella multocida causing fowl cholera by etiology and molecular biology

为确定湖南某鸡场鸡群突然发病死亡的原因,对病料进行细菌分离鉴定,对获得的分离菌株G-2进行了病原学和分子生物学的系统鉴定。通过16S rDNA鉴定和Biolog鉴定,表明该病原菌为多杀性巴氏杆菌杀禽亚种;采用荚膜多重PCR分型、脂多糖多重PCR分型和多位点序列分型对其基因型进行了鉴定,结果显示该菌株为荚膜A型、脂多糖L1型、ST129型。利用SPF鸡进行动物回归试验,结果证实该菌株能引起SPF鸡典型的禽霍乱症状,肌肉注射7 CFU活菌可致死78日龄SPF鸡,10 CFU活菌可致死114日龄SPF鸡。结合临床症状和病理变化,表明引起鸡群死亡的病原为多杀性巴氏杆菌。

In order to determine the cause of sudden death of chicken flocks in a chicken farm in Hunan Province,the isolated strain G-2 was systematically identified using etiological and molecular biological methods.The results of 16 S rDNA and Biolog identification showed that the pathogen was Pasteurella multocida subsp.gallicida.The genotypes were identified by capsular multiplex PCR,lipopolysaccharide multiplex PCR and multilocus sequence typing,which showed that the strain was capsular type A,lipopolysaccharide type L1 and type ST129.The results of the animal regression test in the SPF chickens showed that the isolate induced typical symptoms of avian cholera in the SPF chickens.Intramuscular injection of 7 CFU live bacteria could kill 78-day-old SPF chickens,and 10 CFU live bacteria could kill 114-day-old SPF chickens.The above results showed that the isolate G-2 was Pasteurella multocida causing fowl cholera.