猪链球菌2型感染仔猪致脑炎模型的建立

Establishment of a model of encephalitis caused by Streptococcus suis type 2 infection in piglets

【背景】猪链球菌2型(Streptococcus suis type 2)是危害养猪业重要的病原,给我国养猪业造成了重大的损失,迄今为止仍缺乏猪链球菌2型感染仔猪致脑炎模型,建立合适的模型用于临床药物研发及机制研究为防控该病奠定基础。【目的】构建猪链球菌2型感染仔猪致脑炎模型,通过观察感染仔猪的临床变化、病理学变化、病原分离及PCR鉴定证实模型构建成功。【方法】选取6头健康的三元杂交猪仔猪,随机均分为A、B两组。A组仔猪接种猪链球菌,B组接种生理盐水作为空白对照,观察A组仔猪的临床症状、剖检变化、病理组织学变化。【结果】A组仔猪出现体温升高、精神沉郁、嗜睡以及严重的神经症状,甚至死亡;器官出现严重病变,如脊髓和大脑的神经元细胞的肿胀、坏死、溶解,小脑灰质区浦肯野细胞层和颗粒层见细胞灶状坏死并形成坏死后空腔。【结论】成功构建出猪链球菌2型感染仔猪的脑炎模型。

[Background]Streptococcus suis type 2 is an important pathogen that harms the pig industry and causes significant losses to the pig industry in China.So far,there is still a lack of model of encephalitis caused by Streptococcus suis type 2 infection,so we establish appropriate models for clinical drug development and mechanism research to lay the foundation for prevention and control of the disease.[Objective]Construction of Streptococcus suis type 2 infection in piglets induced encephalitis model,the clinical changes observed in piglets infected,pathological changes,isolation and PCR analysis confirmed successful model building.[Methods]Six healthy ternary crossbred piglets were randomly divided into two groups,A and B.Group A piglets were inoculated with Streptococcus suis,and group B was inoculated with normal saline as the control.The clinical symptoms,necropsy changes and histopathological changes of group A piglets were observed.[Results]Group A piglets had elevated body temperature,depression,lethargy,and severe neurological symptoms,or even death.Severe lesions occur in the organs,such as swelling,necrosis,and dissolution of neurons in the spinal cord and brain.Focal necrosis and post-necrotic space are seen in the purkinje cell layer and granular layer of the cerebellar gray matter.[Conclusion]A model of encephalitis in piglets infected with S.suis type 2 was successfully constructed.