摘要
从北京市郊区数个集约化养鸡场的大肠杆菌感染鸡群的死鸡，毛蛋的心血中分离到３３株细菌，经形态、培养特性及生化反应鉴定为大肠埃希氏杆菌（Ｅｓｃｈｅｒｉｃｈｉａｃｏｌｉ）简称大肠杆菌（Ｅ．ｃｏｌｉ）。对其中１９株作本动物回归试验结果表明，全部为致病性大肠杆菌。从而证明从死鸡（毛蛋）心血中分离到的大肠杆菌与其致病性密切相关。质粒指纹图谱技术是目前医学界用于细菌性疾病流行病学调查，病原追踪的一项新技术，本试验３３株细菌的质粒指纹图谱结果表明，北京郊区数个集约化养鸡场鸡群流行的大肠杆菌感染不是由携带相同质粒的大肠杆菌引起，同时也证明同一鸡场同一鸡群的致病性大肠杆菌以少数几个流行质粒为主。本试验同一来源菌株的质粒指纹图谱相同、但它们的血清型不一致的现象可作为自然条件下同一质粒在不同血清型大肠杆菌中扩散转化的一个分子生物学依据。
Thirty three strains of Escherichia coli(E.coli)had been isolated from heart bloodspecimens of E. coli infected chickens in some farms in Beijing suburb.Nineteen strainsof which were examined for pathogenicity in susceptible 1-day-old-male chicks byinoculated air sac with 0.3ml of nutrient broth culture containing 1.2×10(10)CFU. Allthese 19 strains of E. coli isolated from blood specimens were proved to be virulent E.coli strains.In the screening test of plasmid DNA from 33 strains of E. coli isolates andplasmid DNA fragments generated by restriction endo-nuclease BamHI,simple agarosegel electrophoresis was employed. Results showed that most of E.coli isolates from thesame infected flocks on the same farm had similar plasmid profile, and its fragmentssizes were similar too,and that these isolates had common plasmids.Results fromserological identification tests of 21 stains of E.coli isolates showed that those isolateswhich isolated from the same flocks of chicken and had common plasmid were indifferent sero-types,this comfirmed that plasmids could be transfered in differentsero-types of Esclierichia coli.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
1995年第5期473-480,共8页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
