Can you tell me more about the white muscle disease that affects horses?
White muscle disease, also called nutritional muscular dystrophy, is a degenerative disorder that affects the heart and skeletal muscles in horses and most other farm animals. It is caused by a dietary deficiency of selenium and/or vitamin E. This condition occurs more commonly in young, rapidly growing foals. It has also been infrequently seen in adult horses.
There are two different types of white muscle disease: a cardiac form and a skeletal form. In the cardiac, or heart form, the heart muscle decompensates rapidly, and the animal often develops heart failure and severe respiratory distress; often the horse may be found debilitated or dead. Unlike the cardiac form, the skeletal form typically has a slower onset of muscular weakness or stiffness. Horses may be down and unable to stand. Those that are able to stand often will have some stiffness or leg trembling due to overall weakness of the muscles.
Since the heart is permanently damaged in the cardiac form, treatment for this type of white muscle disease may not be very beneficial. Treatment for the skeletal form is often more rewarding, and involves rest, supplementation with selenium and vitamin E, and supportive care. Your veterinarian will be able to determine the proper dose of supplemental vitamin E and selenium. It is important to feed horses good quality hay and grain that have been properly stored. This will help ensure proper quality of nutrients such as selenium and vitamin E.
12/18/03
