摘要
1993年9月以来,青岛、烟台等地流行一种以产蛋下降为特征的呼吸道传染病。该病主要引起产蛋鸡感染发病,发病后产蛋量下降20～40％。蛋壳颜色变浅、畸形蛋和小蛋增多。1994年5月我们从发病鸡体内成功地分离到一株病毒。电镜观察和动物回归试验证明该分离毒为传染性支气管炎病毒。经SPF鸡胚中和试验证明,分离毒与肾型传支N115和T株血清型有明显差异,与呼吸道型传支Mass株也有很大区别,鉴定为传支变异株。人工攻毒试验表明,该分离毒不能使5和14日龄SPF鸡感染发病,但可使产蛋鸡发病,引起呼吸道症状和产蛋下降。故称之为产蛋鸡传染性支气管炎病毒变异株(YGV)。
Outbreaks of a respiratory-disease characterized by egg reduction had prevailed in regions of Qingdao and Yantai since September1993.mainly affecting the layers with egg reduction by20~40% ,increasing deformed and small eggs and pale eggshell . The isolate got from the diseased layers was proved to be the infectious broncheitis virus by viral isolation, electron microscopy obesrvabron and animal inoculation. It was identified as the variant strain of infectious broncheitis virus, which was significantly distinct from N115 and T serotypes of nephropathogenic IBV,and also quite different from Mass Strain of respiratoryIBV by SPF chicken embryo neutralization test. Experimental challenges showed that the iso-late could not infect 5 and 14 days old SPF chickens but could infect layers,causing respiratory symptoms and egg reduction. Therefore, the isolate was termed as the variant strain of egg-layer infectious broncheitis (YCV).
