Disease Description: Failure of the nervous system to form myelin, seen at birth.

Inherit Mode: The condition is an x-linked trait in the springer spaniel ("shaking pup"). In some other breeds it is believed to be autosomal recessive.

Disease Symptom: Because the proprioceptive system is most affected, pups with this condition have problems with balance, coordination, and positioning. They have a wide-based stance, and appear clumsy (but without weakness). Pups may have what is described as a rocking horse gait. There are pronounced tremors of the head and legs, which are stronger when the pup is excited or moves, and subside at rest or during sleep. Affected pups are normally alert and responsive to their surroundings. Because it is the peripheral nerve myelin that is reduced in Golden retrievers, there is weakness, poor balance and muscleatrophy, but without tremors. Signs are first noticed after birth or when the pups first walks. In breeds other than the springer spaniel, the clinical signs slowly disappear so that dogs are normal by 12-18 months. Because the trait is sex-linked in the springer spaniel, males are most severely affected. By about 2 weeks of age, affected male pups develop a severe tremor of the body, head and legs that decreases during rest and worsens with excitement. They are unable to stand, walk, or eat and generally do not survive unless intensively hand-reared. The disorder is generally fatal by 3 to 6 months of age. Females will be carriers of the trait and may show mild signs as puppies that disappear by 4 to 6 weeks of age.

Disease Cause: -

Disease Diagnose: There are other conditions, primarily affecting the cerebellum, that cause similar signs in newborn puppies. Your veterinarian will do tests to rule out other possible causes.

Treat Method: There is no treatment, but affected puppies (other than springer spaniels) tend to improve over time, often to complete recovery by 12 - 18 months of age.

Breeder Advice: The mother of any affected springer spaniel pup is a carrier and should not be used again for breeding. Breeding of his sisters should also be avoided as they have a 1 in 2 chance of being a carrier, and passing this severe disorder to any male offspring. In other breeds, affected animals (even if recovered to normalcy), their parents (carriers of the trait) and siblings (suspect carriers) should not be bred.

Disease Description Source: Link