TLR4 and infection: The infection of C. perfringens increased the mRNA expressions of TLR-2, TLR-4 and NF-κB (P < 0.01) in jejunal mucosa, whereas the addition of EA in diets decreased the mRNA abundances of TLR-2, NF-κB (P < 0.01) and TLR-4 (P < 0.05).