The course of an illness that resembled osteitis deformans was followed with radiographs and clinical chemistry for 10 months after onset in an adult male macaque. Radiographically, the appendicular bones had thickened cortices, coarse trabeculae, and osteolysis. Serum calcium, phosphorus, and alkaline phosphatase were elevated. Histologically, the long bones of the limbs and calvarium showed the mosaic pattern characteristic of osteitis deformans.
