传染性支气管炎病毒M_(41)株种子批的建立

目的]为生产鸡传染性支气管炎疫苗奠定基础。方法]在研究制备鸡传染性支气管炎疫苗所用毒种的毒力、免疫原性、保存期等的基础上,测定4种来源的传染性支气管炎病毒M41株的50%鸡胚感染量(EID50),选取滴度较高病毒作为毒种,建立传染性支气管炎病毒M41株种子批,并测定其毒力。结果]含毒尿囊液在冻干前后对鸡胚的毒力不变。毒力试验结果表明该毒的毒力中等,可为雏鸡提供保护。M41株种毒的EID50和免疫原性在7代内无变化。湿毒在-15℃保存半年以内,其毒价基本不变。种子批建立后未受到细菌及其他微生物的污染。结论]该种子批可以用于生产鸡传染性支气管炎疫苗。

Establishment of Seed Batches of Strain M41 of Infectious Bronchitis Virus

Objective] The aim of the research was to lay the foundation for producing the vaccine of avian infectious bronchitis(AIB) vaccine.Method] Based on studying the virulence,immunogenicity and preservation period of the used virus seed for preparing AIB vaccines,50% egg infective dose of strain M41 of infectious bronchitis(IB) from 4 kinds of resources were determined.The virus with higher titer was taken as virus seed to establish the seed batches of strain M41 of IB and its virulence was determined.Result] The virulence of allantoic fluid with the virus didn't change before and after freeze drying.The results of virulence test showed that the virulence of the virus was medium and it could provide protection for chicken.The EID50 value and immunogenicity of strain M41 of seed virus had no change in 7 generations.When the damp-toxin was preserved at-15℃ within half a year,its toxic value was essentially constant.The established seed batches were not polluted by bacteria and other microbe.Conclusion] The seed batches could be used for producing AIB.