Ovine CCL11 (C-C motif chemokine ligand 11), also known as eotaxin-1, is a member of the CC chemokine family that regulates eosinophil recruitment and type 2–associated immune responses in sheep (Ovis aries). CCL11 is produced primarily by epithelial cells, fibroblasts, endothelial cells, smooth muscle cells, and activated immune cells in response to Th2-associated cytokines such as IL-4 and IL-13, as well as inflammatory stimuli. It functions predominantly through the CCR3 receptor to promote chemotaxis and activation of eosinophils, and can also influence basophils and Th2 lymphocytes. In healthy sheep, basal CCL11 expression is generally low, but levels increase during parasitic infections—particularly gastrointestinal nematode infections such as Haemonchus contortus and other helminths—as well as during allergic-type inflammation and mucosal immune activation. In veterinary and agricultural research, ovine CCL11 is an important biomarker of Th2-skewed immunity and eosinophilic inflammation, providing insight into host defense against parasites, vaccine responses, and immune regulation in small ruminant production systems.