A型产气荚膜梭菌经小鼠传代的毒力变化

目的:探讨A型产气荚膜梭菌经小鼠腹腔传代后的毒力变化。方法:选择10只小鼠,腹腔注射浓度为5.0×108 cfu/mL的A型产气荚膜梭菌菌液1 mL,记录第一代小鼠存活时间;收集第一代死亡最早的小鼠腹腔内的细菌,经血平板厌氧培养24 h后配制5.0×108 cfu/mL浓度的菌液,并腹腔注射10只小鼠,每只1 mL,记录第二代小鼠存活时间;重复实验并记录第三代、第四代小鼠的存活时间;死亡小鼠腹腔收集的细菌以革兰染色涂片镜检,血平板培养,用API 20A试剂条进行生化鉴定;用SPSS 13.0软件分析每代小鼠的存活时间组间差异。结果:小鼠腹腔收集的标本经革兰染色后均可见两端钝圆棒状的革兰阳性杆菌,血平板厌氧培养均为边缘呈锯齿状有双溶血环的较大菌落,API 20A的结果为产气荚膜梭菌;小鼠存活时间随小鼠腹腔传代数不断延长,第一代与第二代、第三代、第四代之间的存活时间差异有统计学意义,第二代、第三代与第四代两两之间的存活时间差异无统计学差异。结论:A型产气荚膜梭菌经小鼠腹腔第一次传代后毒力显著减弱,随后传代中毒力基本不变,与传统的细菌经动物腹腔培养后毒力增强的观点不一致。

Investigation on Virulence of Clostridium perfringens Type A by Transfer of Culture in Mice

Objective：To investigate the virulence of Clostridium perfringens type A by transfer of culture in mice.Methods：10 mice were abdominal injected by C.perfringens with 5.0×108 cfu/mL for 1 mL,then remarked the survival time as the first generation.Collected C.perfringens type A in the earliest death mouse of the first generation and culture for the second generation mice abdominal injection,remarked the survival tome meanwhile.Reapeat the experiment until finished the forth generation.The survival time of these four groups were analyzed by SPSS13.0.Results：Samples from mice abdominal can observe rob Gram-positive bacteria and some colony can be cultured.Some colony can by cultured with blood plate in anarobic condiction.The colony is proved to be C.perfringens by API 20A test.The survival time had increased by transfer culture in abdominal while first generation＇s is the short and the sequence generations＇ is longer with no statistics difference.Conclusion：The virulence of Clostridium perfringens type A can not increased according transfer of culture in mice.