Fig. 3From: Heterologous prime-boost: an important candidate immunization strategy against Tembusu virusComparative analysis the expression level of IFN-γ and IL-4 of the immunized ducks. The samples (spleen) were collected at 3, 10, 17, 24, 31, 38, 48 and 60 dpi to analyze the levels of cytokines by quantitative RT-PCRBack to article page