摘要
检测了4株猪链球菌2型(Streptococcus suis type 2, SS2)和2株马链球菌兽疫亚种(Streptococcus equi subsp. zooepidemicus, SEZ)对猪、兔的致病性.SS2-1、SS2-H及SS2-006444株均分离自发病猪内脏,前2株毒力因子表现型为MRP+EF+SLY+,后者为MRP-EF-SLY-;SS2-D株为国外引进的SS2人源株,作为对照,其毒力因子的表现型为MRP+EF·SLY+;SEZ-CY和SEZ-CN株均分离自发病猪并经鉴定.SS2-1、SS2-H、SEZ-CY和SEZ-CN株对猪(2～3头/组)的最小致死量分别为106、107、104和108 cfu;对兔(2～3只/组)的最小致死量分别为100～1 000、1 000、 100和105 cfu;SS2-D株108 cfu对猪不致死,对兔的最小致死量为108 cfu,而SS2-006444对猪、兔无致病性.显示SS2毒力因子与其对猪、兔的致病性有关;SS2与SEZ菌株对兔或猪的致病性一致,可用兔取代猪做试验;SS2和SEZ菌株通过腹腔、皮下、肌肉或静脉注射均可感染兔(2～4只/组),并致死,SEZ还可经口、鼻感染;SEZ与SS2静脉感染猪后10 min即可检出细菌,此后2～4 h为无菌血症阶段,之后重新出现.
Pathogenicities of 4 strains of Streptococcus suis type 2 and 2 strains of Streptococcus equi subsp, zooepidemicus to rabbits and pigs were tested. Strain SS2-1 and SS2-H, with virulence factors of MRP ^＋ EF^＋ SLY ^＋ , and SS2-006444, with MRP^- EF^- SLY^ -, were isolated from diseased pigs in Jiangsu. The strain SS2-D, isolated from human patient, was MRP^＋ EF^＋ SLY^＋ for contrast and strain SEZ-CY, SEZ-CN were isolated from diseased pigs. MLD of SS2-1, SS2-H, SEZ-CY and SEZ-CN to pigs （2-3/group） were 10^6, 10^7, 10^4 and 10^8 cfu respectively and MLD to rabbits （2-3/group） were 100 - 1 000, 1 000, 100 and 10^5 cfu respectively, 10^8 cfu of SS2-D couldn＇t cause pigs to death and its MLD to rabbits was l0s cfu. But SS2-006444 was avirulent to rabbits or pigs. It suggested that virulence factors of SS2 was associated with their pathogenicity to rabbits and pigs. All tested strains had the same pathogenicity to rabbits and pigs. SS2 and SEZ could both infect rabbits and cause them to death by inoculation intraabdominally, subcutaneously, intramuscularly or intravenously. SEZ could also infect rabbits intranasally and orally. Bacteremia emerged, firstly in 10 min and again after 4 hours when pigs and rabbits were infected i. v.by these both Streptococci.
出处
《畜牧与兽医》
北大核心
2005年第7期3-5,共3页
Animal Husbandry & Veterinary Medicine
基金
国家"973"(G1999011906)
江苏省科技攻关项目(BE2001372)
关键词
猪链球菌2型
马链球菌兽疫亚种
动物致病性
毒力因子
Streptococcus suis type 2
Streptococcus equi subsp, zooepidemicus
pathogenicity
virulence factor
作者简介
王继春（1975-），男，硕士。
通讯作者。
