The development of dermatitis (scabby-hip) on the hip and thigh of broiler chickens

Broiler chicks grown on litter or in cages at high bird density developed skin lesions on the thigh and hip. Changes in bird denisty markedly influenced lesion incidence (100% at 0.0185 sq m of floor space per bird). The dermatitis was characterized by crusted dry "scabs" at the base of feather follicles and between follicles. The lesions often coalesced to cover wide areas. The scab consisted of a mass of pyknotic nuclei and cellular debris, and when the epidermis was intact there was little inflammatory reaction in the dermis or subcutaneous tissue. The epidermis was destroyed in some lesions, with heterophils penetrating into the subcutaneous tissue. Colonies of gram-positive cocci were present in the lesions.