Polyneuropathy in the malamute is generally characterized by weakness and lack of coordination in the dog's feet and legs. Affected dogs may have a labored gait, appearing to "bunny hop." The rear legs work together in unison to prop the dog up, rather than to propel him. The degree to which a given dog is affected may vary from mild to severe. The dog may fall down, drag his toes, or his gait may just look a little "off-kilter." Exercise intolerance, loss of muscle mass, changes in voice due to an affected larynx and problems swallowing and regurgitating also have been reported. First indications of the problem may be subtle -a dog that no longer jumps up on his dog house, a dog that lies down to eat, a dog that no longer leaps up and down at feeding time or shows a slight tremor in his legs. It cannot be emphasized enough that symptoms may vary considerably from dog to dog.
Age of onset appears to be between 10 to 18 months, though data is lacking. Onset is reported to be quite sudden rather than gradual and progressive. The symptoms may last for six to eight months then abruptly lessen, but they may not go away completely. Symptoms may again appear as the dog ages. Test breedings in Norway indicate that the disorder probably has an autosomal recessive mode of inheritance.
Polyneuropathy does not appear to be common, but its bizarre and variable symptoms create potential for the disorder to be misdiagnosed or to go undiagnosed. The only way to get a positive diagnosis is from a school of veterinary medicine or a veterinary neurologist, who can run tests that most local veterinarians cannot do. Diagnostic tests may include nerve and muscle biopsies, electromyography and nerve conduction velocities. If the results are positive, these tests will show a deterioration of the myelin sheath of the nerve and conductivity may be slower than normal. There has been no effective treatment reported for malamute polyneuropathy, but some dogs do appear to "grow out of it" if they are not so severely affected as to require euthanasia.
Source: Edited from an article written by Vicky MacLean for AMCA and Kyle G. Braund, et al., "Idiopathic Polyneuropathy in Alaskan Malalmutes."