鸡传染性法氏囊病病毒毒力测定方法的改进及国内7个毒株毒力的测定

摘要: 准确衡量鸡传染性法氏囊病病毒(IBDV)毒力特征对研究IBDV毒力变异的分子基础、变异规律，以及影响IBDV毒力的相关分子生物学、病原生物学和细胞生物学机制有重要意义。但是，IBDV的毒力测定方法一直没有一个统一的标准。常规以SFP鸡和商品鸡的死亡率表示IBDV的毒力，但IBDV的定量方法和接种剂量并没有一个统一的标准。研究采用尿囊膜接种途径和灵敏度较高的双抗夹心ELISA方法，大幅度提高EID50定量的灵敏度，使EID50能够准确定量不同致病类型的毒株。SPF鸡和商品鸡的接种剂量根据Eterradossi的研究结果确定为2×103EID50。通过7株中国IBDV的毒力测定及相关分析，证明该方法灵敏度高，重复性好、通用性强, 有利于IBDV毒力测定方法的标准化和规范化。

Improvement of a Method for Determining and Differentiating Virulence of Infectious Bursal Disease Virus (IBDV) Isolates and the Virulence Test of 7 Chinese IBDV Isolates

Abstract: A precise evaluation of virulence of infectious bursal disease virus (IBDV) is very important in studying the regulation of virulence variation and therefore is also important in finding the solutions to IBDV infection. However, the virulence determination method is not standardized. Normally, the virulence of IBDV is expressed as the mortality rate of SPF chicken or commercial chicken with variable inoculation dose, and the virus is titrated accordingly with TCID50、ELD50 or EID50 et al. The aim of the study was to unify IBDV titration route and standardize the method of IBDV virulence determination by greatly increasing the sensitivity of EID50 with chorioallantoic membrane (CAM) inoculation and high sensitive double-sandwich ELISA, hence made it possible to titrate all pathotypes of IBDV by EID50. The inoculation dose was 2×103 EID50 according to the survey report by Eterradossi. The standardized method was proved to be high sensitive, good reproducibility and universal adaptable by the virulence test of 7 Chinese isolates.