摘要 为明确天津市某猪场保育猪疑似发生猪链球菌病的病原菌及其致病力等生物学特性,将猪场一头发病猪扑杀,无菌采集病料于哥伦比亚血琼脂平板上划线培养,对分离的疑似菌株进行形态学观察、生化试验、16S rDNA序列分析和血清型鉴定,确定分离菌株为猪链球菌8型,命名为TJS31。药敏试验结果显示,TJS31株对8种受试药物耐药,4种受试药物中介,1种受试药物敏感。致病性试验结果显示,TJS31株经腹腔接种昆明小鼠,24 h内可以引起小鼠出现精神萎靡、扎堆、呼吸急促、发抖、运动迟缓、死亡等,LD50为1.8×108 CFU/mL。毒力基因检测发现TJS31的毒力基因型为sly+/gdh+/orf2+/gapdh+,不携带mrp、epf和fbps基因。研究结果丰富了我国猪链球菌病病原的生物学资料,为猪链球菌8型的防控提供了依据,也为深入开展猪链球菌8型的致病机制和耐药机理奠定了基础。 In order to determine the biological characteristics of the pathogen and pathogenicity of Streptococcus suis suspected to occur in a pig farm in Tianjin,a sick pig was killed,and the diseased material was collected and cultured on the Columbia blood agar plate.The strain was analyzed through morphological observation,biochemical test,16S rDNA sequence analysis and serotype identification,and the results showed that the strain was identified as Streptococcus suis serotype 8 and was named TJS31.The results of drug sensitivity test showed that TJS31 was resistant to 8 kinds of test drugs,and was intermediated to 4 kinds of test drugs and was sensitive to 1 test drug.The results of pathogenicity test showed that TJS31 strain inoculated into Kunming mice could cause mang symptoms such as mental depression,clustering,shortness of breath,shivering,bradykinesia and death within 24 hours.And the LD50 was 1.8×108 CFU/mL.The virulence gene detection showed that TJS31 had a virulence genotype of sly+/gdh+/orf2+/gapdh+,and did not carry mrp,epf and fbps genes.This study enriched the biological understanding of the pathogen of Streptococcus suis in China,and provided the basis for the prevention and control of Streptococcus suis serotype 8,and laid a foundation for the further development of pathogenic mechanism and drug resistance mechanism of Streptococcus suis serotype 8.
出处 《动物医学进展》 北大核心 2021年第5期19-25,共7页 Progress In Veterinary Medicine
基金 国家重点研发计划项目(2016YFD0801002) 天津市生猪产业技术体系猪病防控岗位项目(ITTPRS2017003) 天津市科技计划项目(20ZYCGSN00050)。
关键词 猪链球菌8型 分离鉴定 耐药特性 毒力基因 Streptococcus suis serotype 8 isolation and identification drug resistance characteristics virulence gene
