In the present study, we found that the mRNA expressions of ISGs including RASD2, OAS1, Mx1, Mx2, IFIT1, and ISG15 in FJzz1-infected LLC-PK1 cells were upregulated significantly in dose-dependent manners, indicating that the innate immune responses mediated by ISGs were induced and activated by FJzz1 infection. This evidence concerns the gene ISG15 and infection.