To examine the in vivo expression levels of duIL-23p19 during the early time points post-infection, the transcript expression profiles of IL-23p19, IL-12p40, IL-17A, and IL-17F in the spleen were investigated at 4, 8, and 12 h post-infection with R. anatipestifer (Fig. 6). The gene discussed is IL17A; the disease is infection.