Nervous system

• Syringomyelia is a condition where a fluid filled sac develops in the spinal cord. The most important cause in dogs is by a Chiari I malformation, which is when an underdeveloped occipital bone interferes with spinal fluid circulation and results in fluid accumulation in the cervical spinal cord. This is a congenital disease most commonly found in small breeds, especially the Cavalier King Charles Spaniel. Signs include ataxia, weakness, and neck pain.
  
• Epilepsy in dogs can be a primary, idiopathic, inherited disorder or secondary to previous head trauma or CNS infections. Idiopathic epilepsy is commonly found in breeds such as German Shepherd Dogs, Beagles, and Dachshunds. The most common sign recurring generalized seizures beginning at a young adult age.
  
• Cerebellar hypoplasia is an incomplete development of the cerebellum. The most common cause in dogs is an in utero infection with canine herpesvirus. It is also seen associated with lissencephaly in Wire-haired Fox Terriers and Irish Setters, and as a separate condition in Chow Chows.
  
• Polyneuropathy is a collection of peripheral nerve disorders that often are breed-related in dogs. Polyneuropathy indicates that multiple nerves are involved, unlike mononeuropathy. Polyneuropathy usually involves motor nerve dysfunction, also known as lower motor neuron disease.
  
• Scotty Cramp is a disease in Scottish Terriers causing spasms and hyperflexion and hyperextension of the legs. It is caused by a disorder in serotonin metabolism that causes a deficiency of available serotonin.
  
• Cauda equina syndrome, also known as degenerative lumbosacral stenosis, in dogs is a compression of the cauda equina by a narrowing of the lumbosacral vertebral canal. It is most commonly seen in German Shepherd Dogs. Signs include pain, weakness, and rear limb muscle atrophy.
  
• Coonhound paralysis is a type of polyradiculoneuritis seen in Coonhounds. The cause has been related to a raccoon bite. Signs include rear leg weakness progressing rapidly to paralysis, and decreased reflexes.
  
• Tick paralysis is a disease in dogs caused by a neurotoxin found in the saliva of female ticks. Dermacentor species predominate as a cause in North America, while Ixodes mainly causes the disease in Australia. There is a gradual onset of signs, which include incoordination progressing to paralysis, changed voice, and difficulty eating.
  
• Dancing Dobermann disease is a type of myopathy that primarily affects the gastrocnemius muscle in Dobermanns. It usually starts between the ages of 6 to 7 months. One rear leg will flex while standing. Over the next few months it will begin to affect the other rear leg.
  
• Granulomatous meningoencephalitis (GME) (including Pug Dog encephalitis and other noninfectious causes of meningoencephalitis) is an inflammatory disease of the central nervous system of dogs. It is a form of meningoencephalitis. The disease is more common in female toy dogs of young and middle age.
  
• Facial nerve paralysis is most commonly caused in dogs by trauma, otitis media, or as an idiopathic condition. Signs include an inability to blink, drooping of the ear, and drooping of the lips on the affected side, although in chronic conditions fibrosis occurs and the ear and lips may appear to be in an abnormal position.
  
• Laryngeal paralysis is unilateral or bilateral paralysis of the larynx. In dogs it can be congenital, seen in the Bouvier des Flandres, Bull Terrier, Dalmatian, Rottweiler and Huskies, or an acquired, idiopathic disease, seen in older Labrador Retrievers, Golden Retrievers, St. Bernards, and Irish Setters. Signs include change in voice and difficulty breathing.
  
• White dog shaker syndrome causes full body tremors in small, white dog breeds. It is most common in West Highland White Terriers, Maltese, Bichons, and Poodles.
  
• Wobbler disease (cervical instability) is a condition of the cervical vertebrae that causes an unsteady gait and weakness in dogs.
  
• Cerebellar abiotrophy is caused by the death of Purkinje cells in the cerebellum. It results in progressive ataxia beginning at a young age. It is most commonly seen in Kerry Blue Terriers and Gordon Setters.