Dolphin CXCL9 (C-X-C motif chemokine ligand 9), also known as MIG (monokine induced by interferon-γ), is a proinflammatory chemokine belonging to the CXC chemokine family, which also includes CXCL10 (IP-10) and CXCL11 (I-TAC) that regulate T-cell recruitment during interferon-driven immune responses. In dolphins (e.g., Tursiops truncatus), CXCL9 is produced by macrophages, dendritic cells, endothelial cells, and epithelial cells in response to interferon-γ (IFN-γ) and inflammatory stimuli during infection or immune activation. CXCL9 signals primarily through the chemokine receptor CXCR3, expressed on activated T lymphocytes, natural killer (NK) cells, and other immune cells, promoting chemotaxis and recruitment of these cells to sites of infection or tissue inflammation. In dolphin health, CXCL9 likely contributes to cell-mediated immune responses against intracellular pathogens, including viral and bacterial infections affecting respiratory and systemic tissues. Because dolphins serve as important sentinel species for marine ecosystem health, studying immune mediators such as CXCL9 helps researchers understand host immune responses to environmental pathogens and pollutants, as well as broader mechanisms of marine mammal immunology and disease susceptibility.