Dynamic replication of AiV genomic copy number was determined using qPCR with AiV VP1 (+), VP1 (-) and 3C-coding region specific primers at 2 to 72 hpi infection, as seen in Figure 6A. In addition, the antiviral response of IFNα and IFNβ, RIG-I, and MDA5 mRNA expression were detected, as seen in Figure 6B. In contrast to a decrease in viral replication with infection time, type I IFN expression peaked at 18–24 hpi and decreased at the late phase of infection, 36–72 hpi. The gene discussed is IFNB1; the disease is infection.