TLR4 and infection: Our findings showed that, in parallel with improving the serum immunological parameters and phagocytic indices, dietary TQN fortifications significantly downregulated the expression levels of TNF-α, IL-8, IL-6 and IL-1β genes and upregulated the transcription levels of IL-10, TLR-4, DEFB1 and TLR-2 genes in rabbits at 96 h post-infection with P. multocida in comparison with the control group.