FIG 1.

DEV inhibits the production of IFN-β and IFN-stimulated genes (ISGs) during infection in DEFs and in ducks. (A to D) DEFs were infected with the virulent DEV CV strain at a multiplicity of infection (MOI) of 0.01. The mRNA levels of IFN-β (A), IL-6 (B), and duck ISGs Mx (C) and OASL (D) were measured by real-time qPCR from 4 to 72 hpi. (E) The expression of DEV protein gE during viral infection in DEFs was monitored by Western blotting. (F to G) 2-week-old specific pathogen-free ducks were inoculated intramuscularly with 10 TCID₅₀ of DEV CV strain, and the mRNA levels of IFN-β (F) and OASL (G) in the spleen samples were measured by real-time qPCR. The relative amounts of IFN-β, IL-6, Mx, and OASL mRNA were normalized to the β-actin mRNA level in each sample, and the fold differences were compared with those in the mock samples. All controls and treated groups were performed and examined in triplicate. *, P < 0.05; **, P < 0.01; ns, no significant difference.