Other interferon-related DEGs down-regulated at both 4 hpi and 8 hpi included two members of the immunity-related GTPase (IRG) family, which is known to facilitate resistance against intracellular bacteria [47,48], and ISG15, which encodes an ubiquitin-like protein and is involved in viral and bacterial infections [49,50,51]. The gene discussed is ISG15; the disease is bacterial infectious disease.