鸭坦布苏病毒病活疫苗（FX2010-180P株）毒种保存期的研究

鸭坦布苏病毒病是新发的一种以蛋鸭产蛋下降为主要特征的传染病,目前仍没有疫苗可预防和控制该病。将鸭坦布苏病毒强毒（FX2010株）在鸡胚成纤维细胞（chicken embryo fi broblasts,CEFs）上连续传代培养180代,获得1株致弱毒株（FX2010-180P株）,利用该弱毒株研制了鸭坦布苏病毒病活疫苗。本研究为了测定鸭坦布苏病毒病活疫苗（FX2010-180P株）毒种的保存期,将-80℃条件下保存了16个月的原始种子批和基础种子批各取3支,进行纯净性检验、鉴别检验以及病毒滴度测定。结果表明,各批次毒种在保存16个月后,病毒纯净无污染,病毒滴度没有明显下降。把基础种子在CEFs上增殖后,低剂量接种鸭子,检验毒种的免疫原性。结果显示,用毒种增殖的病毒免疫原性良好,101.5和102.5 TCID50的剂量可以为接种鸭提供90%和100%的保护。

EVALUATION OF STORAGE LIFE OF MASTER SEED VIRUSES OF DUCK TEMBUSU VIRUS LIVE VACCINE FX2010-180P STRAIN

Duck Tembusu virus （DTMUV） is a newly emerging pathogenic flavivirus causing severe decline of egg production in ducks. However, vaccine is not available for prevention of this infectious disease. An attenuated DTMUV strain FX2010-180P was developed through 180 passages of virulent FX2010 in chicken embryo fibroblasts （CEFs）. To evaluate the storage life of the master seed viruses for production of live vaccine, primary seed and master seed batches were tested for purity, identity and titer after stored for 16 months at-80℃. All batches tested were free from bacteria, mycoplasma and exogenous viruses and viral titers did not decline significantly. To test the immunogenicity of seed viruses, ducks were inoculated intramuscularly with 101.5 and 102.5 TCID50 of vaccine viruses propagated in CEFs. Ducks vaccinated with 101.5 and 102.5 TCID50 of vaccine viruses gained 90%and 100%protection against FX2010 challenge.