中国兽医杂志2025，Vol.61Issue(10)：58-63,6.DOI:10.20157/j.cnki.zgsyzz.2025.10.008
猪链球菌3型临床分离菌株的生物学特性和免疫原性分析
Biological Characteristics and Immunogenicity Analysis of Clinical Isolates of Streptococcus suis Serotype 3
摘要
Abstract
To identify the causative pathogen and investigate its biological characteristics in diseased pigs from a pig farm in Gansu Province,tissue samples including heart,liver,spleen,and joint fluid were collected for pathogen isolation and Gram staining.The isolate was identified through 16S rRNA sequencing and serotyping,followed by analysis of virulence genes,antibiotic susceptibility,growth kinetics,pathogenicity,and immunogenicity.A single isolate of Streptococcus suis serotype 3 was successfully obtained and designated LZS3.Molecular analysis revealed that strain LZS3 harbors three major virulence genes:epf,mrp,and sly.Antibiotic susceptibility testing showed that the strain is resistant to levofloxacin,florfenicol,and ciprofloxacin,but sensitive to amoxicillin and cephalothin.Growth curve analysis showed that LZS3 reaches its growth peak at 8 hours.In a mouse infection model,inoculation with 2.5×10⁸ CFU/mouse LZS3 resulted in 100%mortality,demonstrating strong pathogenicity.Inactivated vaccines formulated with alum adjuvant or GEL02 adjuvant provided 90%-100%protection in mice,indicating excellent immunogenicity.In conclusion,amoxicillin is the preferred therapeutic agent for LZS3 infections.The strain exhibits strong immunogenic potential,supporting its use as a candidate vaccine strain,and provides a scientific support for the prevention and control of S.suis serotype 3.关键词
猪链球菌/分离鉴定/毒力基因/耐药/致病性/免疫原性Key words
Streptococcus suis/isolation and identification/virulence gene/drug resistance/pathogenicity/immunogenicity分类
农业科技引用本文复制引用
张阳,王胜华,赵文昌..猪链球菌3型临床分离菌株的生物学特性和免疫原性分析[J].中国兽医杂志,2025,61(10):58-63,6.基金项目
国家重点研发计划(2023YFD1800504) （2023YFD1800504）
