After death no special lesions are found to exist in the abdominal or thoracic viscera. Many or all the bones of the skeleton are enlarged (fig. 323), spongy in texture, and soft in consistence.

The capsular membranes of the joints of the extremities are much thickened, and the articular ends of the bones are denuded of their cartilage, and present a worm-eaten appearance.

Osteo porosis.

Fig. 323. - Osteo-porosis.

Metacarpals of horse affected by the disease.