Furthermore, we found that C. butyricum suppressed intestinal inflammation by downregulating the TLR4-, MyD88-, and NF-κB-dependent pathways in chickens with Salmonella infection, consistent with previous studies that C. butyricum can decrease pro-inflammatory cytokine levels by inhibiting the NF-κB signaling pathway in broiler chickens with Salmonella infection (Zhao et al., 2017). This evidence concerns the gene TLR4 and Salmonella Infections.