摘要
为查明四川地区某规模化猪场猪发病死亡原因并进行有效防控,试验采集病死猪肺脏组织样本4份进行细菌的分离,并对分离菌株进行菌落形态观察、革兰氏染色和镜检、猪链球菌的PCR鉴定、血清型鉴定、主要毒力基因检测、药敏试验和耐药基因检测。结果表明:从病料中共分离到4株菌,4株分离菌株在胰酪大豆胨琼脂培养基(TSA)中均呈灰白色、针尖状、圆形的菌落,革兰氏染色后镜检可见呈蓝紫色、圆形或卵圆形、链状排列的革兰氏阳性菌,符合猪链球菌的形态特征,分别命名为SYS9、SYS14、SYS15和SYS16。经猪链球菌的PCR鉴定和血清型鉴定确定4株分离菌株均为猪链球菌3型。4株猪链球菌分为2种毒力基因型,SYS9株的毒力基因型为mrp+epf+sly+fbps+cps-orf2+,SYS14、SYS15和SYS16的毒力基因型为mrp+epf+sly+fbps+cps+orf2+;4株猪链球菌均对四环素和泰乐菌素耐药,且均对阿莫西林(青霉素类药物),氟苯尼考和氯霉素(酰胺醇类药物),利奈唑胺(口恶唑烷酮类药物),头孢匹罗、头孢氨苄和头孢拉定(头孢菌素类药物),环丙沙星和左氟沙星(喹诺酮类药物)敏感。除SYS9株仅对四环素和泰乐菌素耐药外,其余3株菌均为3重或3重以上耐药菌株,其中SYS15株为6重耐药菌株。4株猪链球菌均未检出耐药基因ermA、mefA、msrD、fexA、fexB、aph(3′)-Ⅲa、ant(6′)-Ⅰa、aph(2′)-Ⅰb;SYS9株检出耐药基因tetO和ermB,SYS14株检出耐药基因tetM、tetO、ermB、aac(6′)-aph(2″)和optrA,SYS15株检出耐药基因tetM、tetO、tetL、ermB、aac(6′)-aph(2″)和optrA,SYS16株检出耐药基因tetM、tetO、tetL、ermB、aac(6′)-aph(2″)、optrA和Lsa(E)。说明该规模化猪场猪发病死亡原因为猪链球菌3型感染,可使用青霉素类、酰胺醇类、口恶唑烷酮类、头孢菌素类、喹诺酮类药物进行治疗。
In order to identify the cause of pig morbidity and mortality in a large-scale pig farm in Sichuan region and to carry out effective prevention and control,in the test,four samples of diseased and dead pig lung tissues were collected for isolation of bacteria;and the isolates were subjected to colony morphology observation,Gram staining and microscopic examination,PCR identification of Streptococcus suis,serotype identification,detection of major virulence genes,drug sensitivity test and drug resistance gene detection.The results showed that a total of 4 strains of bacteria were isolated from the diseased material;all 4 isolates showed grayish-white,acicular,rounded colonies in TSA solid medium;microscopic examination after Gram staining showed blue-purple,round or oval,chain arrangement Gram-positive bacteria,which were conformed to the morphologic characteristics of Streptococcus suis,and were named as SYS9,SYS14,SYS15,and SYS16,respectively.PCR identification and serotype identification of Streptococcus suis determined that all four isolates were Streptococcus suis type 3.The four strains of Streptococcus suis were classified into two virulence genotypes;the virulence genotypes of strain SYS9 were mrp+epf+sly+fbps+cps-orf2+,and those of SYS14,SYS15,and SYS16 were mrp+epf+sly+fbps+cps-orf2+,and those of SYS15 and SYS16 were mrp+epf+sly+fbps+cps+orf2+.All were resistant to tetracycline and tylosin;all were susceptible to amoxicillin(penicillins),florfenicol,chloramphenicol(aminoglycosides),linezolid(oxazolidinones),cefpirome,cefadroxil,and cephradine(cephalosporins),and ciprofloxacin and levofloxacin(quinolones).Except for strain SYS9,which was resistant only to tetracycline and tylosin,the remaining three strains were 3-or more-drug resistant,with strain SYS15 being 6-drug resistant.None of the four strains of Streptococcus suis detected ermA,mefA,msrD,fexA,fexB,aph(3′)-Ⅲa,ant(6′)-Ⅰa,and aph(2′)-Ⅰb genes;the SYS9 strain detected the tetO gene and the ermB gene;the SYS14 strain detected tetM,tetO,erm
作者
毛从剑
曹冶
于吉锋
吴学婧
谢晶
肖璐
叶勇刚
叶健强
林毅
潘梦
魏勇
李兴玉
张先慧
曾凯
康润敏
MAO Congjian;CAO Ye;YU Jifeng;WU Xuejing;XIE Jing;XIAO Lu;YE Yonggang;YE Jianqiang;LIN Yi;PAN Meng;WEI Yong;LI Xingyu;ZHANG Xianhui;ZENG Kai;KANG Runmin(Sichuan Provincial Key Laboratory of Animal Breeding and Genetics,Sichuan Animal Science Academy,Chengdu 610066,China)
出处
《黑龙江畜牧兽医》
CAS
北大核心
2024年第14期74-80,126,共8页
Heilongjiang Animal Science And veterinary Medicine
基金
四川省重点研发项目面上项目(2021YFN0115)
国家现代农业体系四川创新团队建设项目(Sccxtd-2020-08)
四川省区域创新合作项目(2022YFQ0024,2023YFQ0037)
四川省“十四五”川猪重大科技专项(2021ZDZX0010)
四川省财政运行专项(SASA2022CZYX006)。
关键词
猪链球菌3型
细菌
分离
鉴定
耐药性
耐药基因
Streptococcus suis type 3
bacteria
isolation
identification
drug resistance
drug resistance gene
