Has bactericidal activity. Strongly expressed in the tongue, bone marrow, bursa of Fabricius and trachea. Also expressed in skin, esophagus and air sacs. Weak expression in the large intestine, kidney and ovary. Expressed in the vagina and ovarian stroma, but not in the ovarian follicle. In the vagina expression is higher in laying hens than in non-laying hens, and is higher in older laying hens than in young laying hens. Expression in cultured vaginal cells is increased by LPS and S.enteritidis. Belongs to the beta-defensin family.