Progressive myelopathy and neuropathy in New Zealand Huntaway dogs

Aim: To investigate the nature and cause of a progressive ataxia in three 2 0-month-old Huntaway dogs that were litter mates. Methods: Affected dogs were examined before they were humanely killed and s ubmitted to necropsy. Selected formalin-fixed tissues were examined by ligh t and electron microscopy. Results: The lesions were those of axon and myelin degeneration within sens ory, proprioceptive and motor tracts of the spinal cord and to a lesser deg ree some peripheral nerves. Conclusion: A progressive myelopathy and neuropathy, tentatively described as a central-peripheral distal axonopathy, was present in all 3 dogs. The c ause was not determined but was likely to be either genetic or nutritional. Clinical relevance: In the early stages of this disease, careful examinatio n may be necessary to distinguish the signs of ataxia from orthopaedic dise ase such as hip dysplasia. Affected animals are unlikely to be of use as wo rking dogs.