The results of biological tests have demonstrated that allantoic fluid of the first passage virus did n ' t produce macroscopic pathogenic role to chicken embryos and after passaged for four times , gross lesions were observed in chicken embryo . the virus showed typical coronavirus under electron - microscope and it could n ' t form plaque in cef cells and could hemagglutinates chicken red blood cells after treatment with 1 % trypsin . to surprise , the virus replicated in cef cells also showed hemagglutination activity to chicken red blood cells . in addition , the spf chickens which inoculated with the virus isolated from the chicken damaged tissue showed clinical sign and grow lesion , but it ' s gross lesion did n ' t resemble to those of field outbreaks 生物学特性：鸡胚尿囊液经离心、磷钨酸负染后，电镜观察该病毒为典型的冠状病毒；该毒株的第一代尿囊液对鸡胚无肉眼可见的致病作用，当继代到第5代后，胚体严重病变；病毒在鸡胚中随着接种时间的延长，其效价增高， 96h可达到48h的2倍；该毒株可在cef上生长，但不能形成明显的蚀斑；经1胰酶处理后可凝集鸡红细胞；鸡胚的第四代尿囊液病毒回归动物体，病死鸡肾脏呈典型的花斑肾，腺胃则未见肉眼可见的病变。
