A study of pathology of a bovine primary peripheral myelinopathy with features of tomaculous neuropathy.

Cases of a bovine neuropathy are reported in which peripheral nerves show "sausage-shaped" thickenings of the myelin sheaths at different sites of the internode. Clinical signs of dysphagia and chronic rumenal bloat developed after weaning which were attributable to bilateral vagus nerve degeneration. Trunks of the sciatic nerves and brachial plexuses were similarly affected with the animal adopting a weak shuffling gait. Affected animals were the progeny of sire-daughter matings. The lesions are similar to those seen in the tomaculous neuropathies of man. The present study is believed to be the first report of this lesion occurring in domestic animals.