摘要
为鉴定新疆石河子地区某规模化牛场表现呼吸道感染症状荷斯坦病牛的细菌性病原及其分离株的血清型、耐药基因和毒力基因携带情况,本研究无菌采集病死牛病变组织,采用常规细菌分离培养及PCR方法鉴定细菌,采用PCR方法检测其血清型、耐药基因和毒力基因携带情况,采用K-B纸片法检测其耐药表型。结果显示,从病变组织样品中分离了4株荚膜A1型的溶血性曼氏杆菌(Mh-1、Mh-2、Mh-3、Mh-4);耐药表型显示4株Mh对β-内酰胺类(青霉素)、氨基糖苷类(链霉素)和糖肽类(替考拉宁)药物耐药;耐药基因仅检测到β-内酰胺类基因blaTEM;分离菌株Mh-1携带8类9种毒力基因中的5种(LKT-C、gs60、fbpA、gapA、ptfA),Mh-2携带其中的4种(LKT-C、plpB、dnaN、ptfA),Mh-3携带其中的7种(LKT-C、plpB、gs60、fbpA、gapA、dnaN、ptfA),Mh-4携带其中的6种(LKT-C、plpB、gs60、fbpA、gapA、ptfA)。同时分离出1株荚膜A型,脂多糖L3型的多杀性巴氏杆菌(Pm-1);Pm-1仅对克林霉素耐药;Pm-1携带6类12种不同的毒力基因(exbD、tonB、hsf2、ptfA、oma87、ompA、ompH、plpB、psl、nanB、tbpA、pmHAS)。将Mh和Pm-1均以3.2×10^(8) cfu/mL的剂量感染30只小鼠进行致病性试验,结果显示,4株Mh感染小鼠于3 d内陆续全部死亡,Pm-1感染小鼠于10 h内全部死亡,表明分离菌株Mh和Pm-1均携带致病性毒力基因,且具有较强的致病性。结果表明,新疆石河子地区某集约化牛场表现为呼吸道症状病死牛的细菌性病原是牛源Mh和Pm混合感染,两者均携带与呼吸道粘附侵染相关的IV型菌毛基因ptfA,且Pm-1株主要对青、链霉素耐药,对大多数药物较敏感,为本地区牛呼吸道疾病综合征的流行病学调查与临床治疗提供参考依据。
To investigate the bacterial pathogens and the serotypes,drug resistance genes and virulence genes of the isolated strains in Holstein cattle with respiratory tract infection symptoms in a large-scale cattle farm in Shihezi,Xinjiang,the visceral tissues of dead cattle were collected aseptically,and the bacteria were identified by conventional bacterial isolation and culture and PCR method.The serotypes,drug resistance genes and virulence genes and drug resistance phenotypes were analyzed by PCR method and disk method.The results showed that four strains of Mannheimia haemolytica(Mh-1,Mh-2,Mh-3 and Mh-4)were successfully isolated from diseased tissues and identified as capsularis type A1.The drug resistance phenotype showed resistance toβ-lactams(Penicillin),aminoglycosides(Streptomycin)and glycopeptides(Teicoplanin).Onlyβ-lactam resistance gene blaTEM was detected.The isolates Mh-1 carried five kinds of virulence genes(LKT-C,gs60,fbpA,gapA,ptfA)belonging to eight categories and nine kinds,Mh-2 carried four kinds(LKT-C,plpB,dnaN,ptfA),Mh-3 carried seven kinds(LKT-C,plpB,gs60,fbpA,gapA,dnaN,ptfA),and Mh-4 carried six kinds(LKT-C,plpB,gs60,fbpA,gapA,ptfA).Meanwhile,a strain of Pasteurella multocida(Pm-1)was isolated and identified as capsule type A and lipopolysaccharide type L3.Pm-1 is resistant only to clindamycin,it carried twelve different virulence genes(exbD,tonB,hsf2,ptfA,oma87,ompA,ompH,plpB,psl,nanB,tbpA,pmHAS)belonging to six types.Thirty-five mice were infected with the Mh and Pm isolates at a dose of 3.2×10^(8)cfu/mL,respectively,and the pathogenicity of the isolates was analyzed.The results showed that mice infected with four strains of Mh died within three days,and five mice infected with Pm isolate died within ten hours,indicating that all of the isolates carried pathogenic virulence genes had strong pathogenicity.The results showed that the bacterial pathogens of dead cattle with respiratory symptoms in an intensive cattle farm in Shihezi area of Xinjiang were Mannheimia haemolytica and Pasteurell
作者
贾开文
操义恒
王子杰
胡亚辉
周霞
黄新
钟发刚
吴桐忠
韩猛立
张星星
张倩
JIA Kai-wen;CAO Yi-heng;WANG Zi-jie;HU Ya-hui;ZHOU Xia;HUANG Xin;ZHONG Fa-gang;WU Tong-zhong;HAN Meng-li;ZHANG Xing-xing;ZHANG Qian(College of Animal Science and Technology,Shihezi University,Shihezi 832003,China;State Key Laboratory for Sheep Genetic Improvement and Healthy Production Xinjiang Academy of Agricultural and Reclamation Science,Shihezi 832000,China)
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2023年第2期201-206,共6页
Chinese Journal of Preventive Veterinary Medicine
基金
新疆兵团重点领域科技攻关计划项目(2019AB029)
兵团重点领域科技攻关计划(2021AB012)
新疆农垦科学院优秀中青年人才培养引导计划专项(SKLSGIHP2021A02)。
关键词
牛呼吸道感染
多杀性巴氏杆菌
溶血性曼氏杆菌
耐药表型
耐药基因和毒力基因
bovine respiratory tract infection
Pasteurella multocida
Mannheimia haemolytica
drug resistance phenotype
drug resistance genes and virulence genes
