Neuroaxonal dystrophy of Rottweiler dogs.

Five Rottweiler dogs were examined because of progressive ataxia of thoracic and pelvic limbs of several months' to 4 years' duration. Hypermetria, especially of the thoracic limbs, and head incoordination and tremors were obvious features in the 3 older dogs. None of the dogs had evidence of weakness or loss of conscious proprioception. An electroencephalogram in 1 severely affected dog was normal. Electromyograms in 2 severely affected dogs were normal except for some positive sharp waves and fibrillation potentials in the interosseus muscles of all 4 feet. Cerebrospinal fluid evaluations of 2 severely affected dogs were normal. A reduced number of sensory nerve endings, compared with age-matched controls, was seen on histologic examination of a conjunctival biopsy specimen in 1 severely affected dog. An antemortem diagnosis of neuroaxonal dystrophy was suspected from the signalment, history, and neurologic examination findings. The diagnosis was confirmed on the basis of microscopic findings in 3 dogs necropsied.