TLR4 and infection due to clostridium perfringens: In line with other studies (Jung et al., 2015; Rajput et al., 2017), we found that at the peak period of C. perfringens infection (2 DPI), adding B. licheniformis or enramycin to the diet significantly increased the jejunal mRNA expression of TRIF and NF-κB in broilers, which indicates the activation of TLR-NF-κB signaling pathway, although the mRNA levels of TLR-4 and TLR-2 were not changed.