Bovine CCL3 (C-C motif chemokine ligand 3, also known as MIP-1α, macrophage inflammatory protein-1 alpha) is a pro-inflammatory chemokine that regulates recruitment and activation of immune cells during inflammatory and infectious responses in cattle (Bos taurus). CCL3 primarily signals through the CCR1 and CCR5 receptors, promoting chemotaxis of monocytes, macrophages, natural killer (NK) cells, dendritic cells, and activated T lymphocytes to sites of infection or tissue injury. In cattle, CCL3 is produced by activated macrophages, dendritic cells, epithelial cells, and lymphocytes in response to inflammatory stimuli such as microbial components and cytokines including TNF-α and IL-1β. CCL3-mediated immune cell recruitment plays an important role in host defense against pathogens involved in diseases such as bovine respiratory disease complex (BRDC), mastitis, and mycobacterial infections including Mycobacterium bovis. While CCL3-driven leukocyte trafficking supports pathogen clearance and initiation of immune responses, excessive or prolonged expression may contribute to inflammatory tissue damage and chronic inflammation. As a regulator of immune cell migration and inflammatory signaling, bovine CCL3 is widely studied in investigations of host–pathogen interactions, inflammatory disease mechanisms, and vaccine responses aimed at improving disease resistance and health in cattle.