Focusing on the functions of the DEGs, in the head kidney (Figure 3A), only three KEGG pathways were significantly modified upon infection (the neuroactive ligand–receptor interaction, the synaptic vesicle cycle, and the insulin secretion pathways), while in the liver (Figure 3B), there were 12 pathways related to autophagy, phagosome, cholesterol and lipid metabolism, cell cycle and renewal, and innate acute response through complement pathways. The gene discussed is INS; the disease is infection.