Ovine/Caprine amphiregulin (AREG) is a member of the epidermal growth factor (EGF) family and functions as a ligand for the epidermal growth factor receptor (EGFR/ErbB1), where it regulates epithelial cell proliferation, differentiation, survival, and tissue repair. The amphiregulin protein sequence is identical in sheep (Ovis aries) and goats (Capra hircus), enabling cross-species detection and translational applicability in small ruminant research. In both species, amphiregulin is produced by epithelial cells, keratinocytes, fibroblasts, and activated immune cells—including Th2 cells and regulatory T cells—in response to tissue injury, inflammation, allergen exposure, and microbial stimulation. Through activation of EGFR-dependent signaling pathways such as MAPK and PI3K/AKT, ovine/caprine amphiregulin contributes to mucosal barrier maintenance, wound healing, tissue remodeling, and regulation of inflammatory responses in respiratory, gastrointestinal, mammary, and cutaneous tissues. Dysregulated expression may be associated with chronic inflammation, fibrosis, mastitis-related tissue remodeling, parasitic infections, and neoplastic processes. In veterinary and comparative medicine research, amphiregulin is of interest in small ruminant models of respiratory disease, gastrointestinal inflammation, wound repair, mammary gland biology, and translational studies of EGFR-mediated signaling pathways. Characterizing amphiregulin expression in sheep and goats provides valuable insight into epithelial–immune crosstalk, regenerative mechanisms, and inflammatory regulation in agricultural and biomedical research contexts.