3.3 Virus isolation and identification
One FPV strain, designated FPV HNZZ-2, was successfully isolated from a sample from Zhengzhou Province, China. The results showed that cytopathogenic effects observed in infected CRFK at 24h post-inoculation included, swelling, netting, and shedding. However, the negative CRFK control group showed uniform cell morphology with obvious borders and good condition (Figure 3).