Chicken IL-17B (Interleukin-17B) is a member of the IL-17 cytokine family that contributes to regulation of inflammatory and immune responses in chickens (Gallus gallus). IL-17B is expressed by a variety of cell types, including epithelial cells and immune cells, particularly in response to microbial infection or inflammatory stimulation. Although less characterized than IL-17A, IL-17B is believed to signal through the IL-17RB receptor to modulate production of pro-inflammatory cytokines and chemokines, thereby influencing heterophil recruitment and mucosal immune responses. In healthy chickens, basal IL-17B expression is generally low but can increase during bacterial, viral, or parasitic infections, as well as following vaccination or immune challenge. In poultry immunology research, chicken IL-17B is of interest for its role in regulating mucosal inflammation, host defense in the respiratory and gastrointestinal tracts, and modulation of Th17-associated pathways. Characterization of IL-17B in chickens provides insight into avian inflammatory signaling networks and immune regulation relevant to disease resistance and vaccine development in commercial poultry systems.