Encephalomyelitis and myositis in a boxer puppy due to a Neospora-like infection.

A 10-week-old Boxer dog from Uppsala, Sweden, was killed because of hind limb paralysis. The hind limb muscles were grossly atrophied and encephalomyelitis and myositis were the predominant microscopic lesions. Neospora caninum-like tachyzoites were found in the brain and skeletal muscles, and tissue cysts were found in the brain. The organism was not Toxoplasma gondii, as T. gondii antibody was not found in the indirect fluorescent antibody test in serum samples from the puppy and the dam, and the organism in the dog's brain did not react with T. gondii antibody in the immunoperoxidase test.