1株猪源病原菌的分离鉴定及部分生物学特性研究

通过对一起病死猪的实验室诊断 ,从病猪心血、脏器中分离到了 1株对小白鼠和家兔都具有较强致病性的细菌。经显微镜观察、培养特性观察、生化特征鉴定 ,此菌为多杀性巴氏杆菌 ,但此菌与其他多杀性巴氏杆菌不同的是它能利用水杨素、鼠李糖、阿拉伯糖。 O抗原琼脂扩散试验鉴定此菌菌体抗原为 O1型 ;Carter间接血凝试验法检验荚膜抗原类型此菌为 A型。体外滤纸扩散法检验此巴氏杆菌对药物敏感性 ,试验表明该菌耐青霉素、土霉素、四环素、磺胺嘧啶、痢特灵、阿米卡星、头孢唑啉 ;但对庆大霉素、卡那霉素、盐酸环丙沙星、氟哌酸敏感 ,对氨苄西林 ,链霉素中度敏感。自制灭活苗进行免疫原性实验检测 ,本分离菌疫苗对小白鼠和家兔保护率约为 70 % ,而市售巴氏杆菌疫苗对小白鼠和家兔保护率约为 3 0 %～ 40 %。

Isolation and Identification of a Strain Pathogen from Pig

A virulent bacteria which can kill KM mouse and rabbit was isolated from the viscera & heart blood of sick swine in diagnosis. It was identified as Pasteurella multocida according to microscopy observation,culture characters and biochemical characters.But it was different to other Pasteurella multocida that the bacteria could utilize salicin, rhamnose and arabinose. It had O_1 antigen as determined by agar diffusion test and the capsular antigen type A as determined by Carter method with the indirect agglutination test. Drug resistance was tested in Vitrs with filter paper diffusion method. The pathogenic bacteria have had drug resistance to penicillin, oxytetracycline tetracycline, sulfadiazine, furazolidon, amikacin, cefazolin etc, but it still kept sensitivity to gentamicin, kanamycin, ciprofloxacin, norfloxacin. Ampicillin and streptomycin had only partial effect to them. The Pasteurella multocida was inactivated and made into bacterin. Its immunogenicity and protecting capability were tested by injecting KM mouse and rabbit, meanwhile the control group was injected with type B Pasteurella bacterin. After the attacking of the Pasteurella multocida in broth culture,70% experimental animal survived, but there was only 30%~40% in control group.