MYD88 and infection: However, at 6-day post-infection, gene expressions for TLR4, MyD88, and NF-κB in liver, spleen, and cecal tissues were elevated significantly (P < 0.05) in the PC group compared to NC and EXP groups (P < 0.05), but no significant differences were found between EXP and NC groups (P > 0.05) (Tables 7–9).