In the present study, immune-related genes (il-8, tor, nf-κb p65, myd88, mhc-2, piscidin, etc.)were extensively upregulated in the head kidney of group L 48 h after V. Harvey infection, whereas the upregulation of immune-related genes was not detected until 96 h after infection in groups M and H. MyD88 is an important transduction protein that regulates adaptive immunity-related pathways, mediates the activation of most TLRs, and induces the activation of interferon regulatory factors [67]. This evidence concerns the gene CXCL8 and infection.