Proventricular Dilatation Disease

Proventricular Dilatation Disease is a disease affecting psittacines (Parrots). It was first recognized and described in 1978 by Dr. Hannis L. Stoddard. Since the first reported cases were involving species of Macaw, the condition was termed Macaw Wasting Syndrome.

The symptoms of the illness are varied but invariably include a problem in food digestion, tiredness, sleepiness and rapid loss of weight, followed by death. The food is passed undigested, so the bird's body relies on its reserves of fat, and since they are quite small in most birds, the bird dies within a few weeks.

In autopsies it has been found that the nerve supply to the digestive tract is being disabled, impairing its function and slowing down the passage of food through the digestive tract. The proventriculus (or crop) has been dilated as the bird keeps eating, but the food is not being processed fast enough in the ventriculus and the intestine.

There is currently much research being undertaken to identify the cause of the disease, which is yet unknown. It is known, though, that the condition is infectious and still terminal.