重庆屠宰场猪链球菌感染的调查  

Investigation on Streptococcus suis infection in some slaughterhouses of Chongqing

作　　者：都玉 刘召颖 彭泽仁 吴宗福[1,2,3] DU Yu;LIU Zhaoying;PENG Zeren;WU Zongfu(College of Veterinary Medicine,Nanjing Agricultural University,Nanjing 210095,China;Key Lab of Animal Bacteriology,Ministiy of Agriculture and Rural Affairs,Nanjing 210095,China;OIE Reference Lab for Swine Streptococcosis,Nanjing 210095,China)

机构地区：[1]南京农业大学动物医学院,江苏南京210095 [2]农业农村部动物细菌学重点实验室,江苏南京210095 [3]世界动物卫生组织猪链球菌病参考实验室,江苏南京210095

出　　处：《畜牧与兽医》2022年第6期58-65,共8页Animal Husbandry & Veterinary Medicine

基　　金：国家自然科学基金面上项目(31872469)。

摘　　要：旨在调查2021年重庆地区屠宰场表观健康猪群中猪链球菌的血清型、耐药和毒力特征,为制定该地区猪链球菌病的防控策略提供参考。以2021年重庆地区屠宰场表观健康猪扁桃体样品为试验材料,分离猪链球菌并对菌株进行血清型分型、耐药基因检测、药敏试验、斑马鱼毒力试验,分析猪链球菌的流行特征。结果显示:2021年5—6月于重庆屠宰场共采集表观健康猪扁桃体154份,检出猪链球菌阳性样本80份(51.95%),从中分离到菌株87株;主要血清型分别为16型(16.09%,14/87)、9型(9.20%,8/87)、4型(8.05%,7/87),而血清2型检出率较低,占比4.60%(4/87)。分离株对林可酰胺类、四环素类、大环内酯类抗生素耐药率较高,分别为100%(87/87)、95.40%(83/87)、93.10%(81/87);对氨基糖苷类抗生素耐药率为59.77%(52/87);对利奈唑胺、β-内酰胺类、万古霉素、利福平的耐药率较低,分别为5.75%(5/87)、5.75%(5/87)、0(0/87)、0(0/87);96.55%(84株)的菌株对3类及以上的抗菌药耐药,属于多重耐药菌株。选取19株猪链球菌代表菌株进行斑马鱼攻毒试验,结果显示78.95%(15/19)的菌株对斑马鱼致死率≤33.33%,但血清3型菌株2021WUSS071和新荚膜基因簇-7(NCL-7)菌株2021WUSS102对斑马鱼的致死率高,分别为93.33%、86.67%,属于强毒株;菌株2021WUSS067和2021WUSS082对斑马鱼的致死率分别为60.00%、40.00%,属于中等毒力菌株。研究表明,重庆地区屠宰场猪群中猪链球菌流行率较高且血清型复杂,绝大多数菌株属于多药耐药,且存在毒力较强的菌株,需引起重视。The serotype,antimicrobial resistance,and pathogenic characteristics of Streptococcus suis isolated from healthy pigs from slaughterhouses in Chongqing in 2021 were investigated here in the hope of providing reference for the formulation of prevention and control strategies for the disease caused by S.suis.S.suis was isolated from tonsil samples collected from healthy pigs in slaughterhouses in Chongqing in 2021.Serotyping,the detection of antimicrobial genes,the drug sensitivity test,and zebrafish infection experiments were performed.From May to June 2021,154 tonsils from healthy pigs were collected in slaughterhouses in Chongqing,and 80 samples(51.95%)were S.suis positive.Of the positive samples,87 S.suis strains were isolated.The detection rate of serotype 16 was the highest,accounting for 16.09%(14/87),followed by serotype 9(9.20%,8/87)and serotype 4(8.05%,7/87),while that of serotype 2 was quite low,accounting for 4.60%(4/87).The isolates were highly resistant to lincosamides(100%,87/87),tetracyclines(95.40%,83/87),and macrolides(93.10%,81/87).59.77%(52/87)of the strains were resistant to aminoglycosides.The resistant rate to linezolid(5.75%,5/87),β-lactam antibiotics(5.75%,5/87),vancomycin(0,0/87),and rifampicin(0,0/87)was quite low.84 strains(96.55%)showed a multidrug-resistant phenotype.Zebrafish infection experiments showed that the lethality of 78.95%(15/19)of the strains was lower than or equal to 33.33%.However,the lethality of the serotype 3 strain 2021WUSS071 and the NCL-7 strain 2021WUSS102 was 93.33%and 86.67%,respectively,which were highly virulent.The lethality of the strains 2021WUSS067 and 2021WUSS082 to zebrafish was60.00%and 40.00%,respectively,which were moderately virulent.The prevalence rate of S.suis among healthy pigs in slaughterhouses in Chongqing was quite high,and the serotypes of the isolates were diverse.Most of the strains were multidrug-resistant,and some strains were highly virulent.

关 键 词：猪链球菌 健康猪 耐药 毒力 重庆 

分 类 号：S858.28[农业科学—临床兽医学]