产酸克雷伯菌毒力强弱及对小鼠机体影响的研究

Study on the virulence of Klebsielia oxytoca and its influence on mice

目的 了解产酸克雷伯菌的毒力强弱及感染小鼠机体的组织病理学变化。方法 实验菌株以不同的浓度分别给予实验小鼠,计算其半数致死量(LD_(50)),观察小鼠临床症状及组织病理学检查。结果 5株菌的LD_(50)分别是1. 516 MCF/kg·BW、1. 516 MCF/kg·BW、2. 472 MCF/kg·BW、1. 231 MCF/kg·BW、3. 249 MCF/kg·BW。实验动物染菌后,于4 h~6 h开始出现被毛逆立、颤抖、呼吸急促、嗜睡、弓背等现象。死亡动物肛门处均有污秽;7 h,4 MCF和8 MCF剂量组的动物开始死亡;48 h后,未再见动物出现死亡。经对死亡小鼠心血和腹腔液的即时细菌培养,分离得到原感染菌株;对照组无动物死亡,感染小鼠多器官发生组织病理学改变,多器官为典型的败血症病变。结论 产酸克雷伯菌具有较强的致病性,可致暴露动物机体发生器质性病变和死亡。

Objective To understand the vinulence of Klebsiella oxytoca and histopathological changes of the infected mice which were caused by Klebsiella oxytoca.Methods The test strains were injected into mice with different concentrations to evaluate the medium lethal dose(LD_(50))and observe the clinical symptoms showed by experimental mice and histopathological exarnination results.Results The LD_(50) of five strains were 1.516 MCF/kg.BW,1.516 MCF/kg.BW,2.472 MCF/kg.BW,1.231 MCF/kg.BW and 3.249 MCF/kg·BW.respectively.After infected with the bacteria,the mice of the test group showed symptoms of hair inversion,quivering,shortness of breath,drowsi ness and back arch.After infected with the bacteria,the mice of the test group showed symptoms of hair inversion,quivering,shortness of breath,drowsiness and back arch in4 h-6 h.In addition,the contaminants can be found around the anuses of the dying mice.In addition,the contaminants can be found around the anuses of the dying mice.After 7 h,animals in the 4 MCF and 8 MCF dose groups began to die;after 48 hours,no other animals were found dead.By taking advantage of instant bacterial culture of cardiae blood and peritoneal fluid of died mice,the original infectious bacteria were isolated.No death was found in control group,pathological changes(typically septi-cemia lesions)in mutiple organs of infected mice were observed.Conclusion Klebiella oxytoca has strong pathogenie ffect,which causes pathological changes of multiple organs and deaths of infected mice.