Moreover, the expression of immune-related genes (SAA, iNOS, IL-1 β, IL-6, IL-10, TNF α, C3, MHC I, MHC II, CD4, CD8, TCR α, IgM, IgD and IgZ) increased in all groups post infection, which was more significant in the vaccinated groups. The gene discussed is C3; the disease is infection.