Hypercalcemia and calcinosis in Florida horses: implication of the shrub, Cestrum diurnum, as the causative agent.

A chronic debilitating disease is described in Florida horses. There is progress weight loss and lameness of increasing severity. Plasma calcium is elevated to moderate or severe degree. Anatomical changes include dystrophic calcinosis of elastic tissues, viz. major arteries, tendons and ligaments. A generalized osteopetrosis is present and may be related to hypoparathyroidsim and hypercalcitoninism. The presence of Cestrum diurnum (day-blooming jessamine, day cestrum, wild jasmin) in areas accessible to affected animals, the observation that leaves of the plant were stripped in these areas, and the finding of a potent, active vitamin D-like substance in this plant constitute strong evidence that Cestrum diurnum is the agent causing the abnormalities of mineral metabolism.