One of the chronic progressive disorders of the spinal cord in dogs is the degenerative myelopathy (DM). The most predisposed age in dog is 5 to 14 years, while rarely noted in younger, there is no gender predisposition. This disorder most commonly appears in dogs of the German shepherd breed, but it can appear in other breeds too. The main changes about this disease are degeneration of the myelin, especially in the thoracic-lumbar segments of the spinal cord and the dorsal nerve roots. The progression of the disease is slow and can last months to years. Undoubtedly, diagnosis is made by examinations of the CSF and establishing elevated level of protein segments.