摘要
选取3个流行病学背景不同的猪链球菌2型菌株人工感染西藏小型猪,探讨西藏小型猪作为猪链球菌2型毒力评价模型动物的可行性。12头西藏小型猪分成4个组,A组为阴性对照组接种肉汤培养基;B、C、D三组分别接种猪链球菌2型分离株GZ06-122B、SH06-21D和HA9801。GZ06-122B株和SH06-21D株分离自华南地区健康猪的扁桃体,毒力基因表型分别为sly-/mrp-/ef-和sly+/mrp+/ef+。HA9801株分离自江苏患败血症死亡的猪体内,毒力基因表型为sly+/mrp+/ef+。接种GZ06-122B株的试验猪无明显的临床症状,体温不升高,血液循环中也无细菌出现;试验猪感染SH06-21D株和HA9801株后临床症状相当严重,尤其是感染HA9801株后,出现体温升高、跛行和神经症状,甚至死亡。攻毒后1周内,C组试验猪病死1头,D组病死2头。从而表明HA9801株有很强的毒力,SH06-21D株次之,GZ06-122B株的毒力较弱,证实了西藏小型猪对猪链球菌2型易感,且可用于区分不同猪链球菌2型分离株的毒力强弱。
Three Streptococccus suis type 2 strains were selected to infect Tibet mini-pigs in order to evaluate an experimental model with Tibet mini-pigs.Twelve piglets were allotted in 4 separated groups.Group A consisted of negative control animals which received broth medium.Groups B,C,and D were intravenously challenged with 2 mL of S.suis,strains GZ06-122B,SH06-21D and HA9801,respectively.The strain GZ06-122B and SH06-21D were isolated from tonsils of slaughter pigs in south of China,and genetype were sly-/mrp-/ef-and sly＋/mrp＋/ef＋.The strain HA9801 was isolated from dead pig in Jiangsu.Pigs inoculated with strain GZ06-122B did not present clinical signs of S.suis infection.Contamination in organs and bacterial blood circulation were rare and lesions were almost non-existent.Infection of pigs with S.suis strain SH06-21D（group C） and HA9801（group D） caused severe clinical problems,animals infected with S.suis HA9801 were the most affected.Pigs presented clinical signs such as high body temperature,lameness,nervous symptoms,and even death.One week after inoculation,1 pig died in group C and 2 pigs died in group D.It can be concluded that S.suis strain HA9801 is most virulent,followed by SH06-21D and GZ06-122B.The results demonstrated that an experimental model with Tibet mini-pigs can be used for discriminating the virulence of different S.suis type 2 strains.
出处
《动物医学进展》
CSCD
北大核心
2011年第4期15-18,共4页
Progress In Veterinary Medicine
基金
2005年粤港关键领域重点突破项目(2005A10905006)
2008年公益性行业科研专项(200803016)
关键词
猪链球菌2型
西藏小型猪
动物模型
Streptococcus suis type 2
Tibet mini-pig
animal model
