Equine motor neuron disease (EMND) is a diffuse
neurodegenerative disorder affecting the somatic, lower motor neurons of horses. It affects the nerves that supply the direct neurological input into all muscles resulting in muscles atrophy.
The exact cause is unknown, but vitamin E deficiency is a primary risk factor. Vitamin E levels were significantly lower in affected horses. Some horses have improved after being allowed on pasture and given
supplemental vitamin E.