Swine Interferon Omega 5 (IFN-ω5) is a type I interferon cytokine involved in the innate antiviral immune response in pigs (Sus scrofa). IFN-ω5 is produced primarily by virus-infected cells and immune cells following recognition of viral nucleic acids by pattern recognition receptors such as Toll-like receptors (TLRs) and RIG-I–like receptors. Swine IFN-ω5 binds to the type I interferon receptor complex (IFNAR1/IFNAR2) expressed on many immune and non-immune cells, activating intracellular signaling through the JAK–STAT pathway, particularly STAT1 and STAT2, which leads to the formation of the ISGF3 transcription complex and induction of numerous interferon-stimulated genes (ISGs) that inhibit viral replication and enhance antiviral defenses. In pigs, IFN-ω5 contributes to the establishment of an antiviral state, modulation of innate and adaptive immune responses, and regulation of inflammatory signaling. Swine IFN-ω5 is studied in veterinary immunology and infectious disease research, particularly in porcine viral disease models such as porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza virus, where type I interferon responses including IFN-ω5 play an important role in early antiviral immunity and host defense.