Carebellar Hypoplasia

Cerebellar hypoplasia is a condition in which parts of the cerebellum have not completely developed. The cerebellum makes up a large part of the brain, lying under the cerebrum and toward the back, above and behind the brainstem. This condition can occur due to intrinsic (genetic) causes, or to extrinsic causes like infections, toxins or nutritional deficiencies.

Affected puppies have normal mental alertness. In this condition, in contrast to cerebellar abiotrophy, signs of cerebellar dysfunction are evident at birth or by 2 weeks thereafter, and do not get worse as the pup ages. Other than the abnormalities in balance and coordination, the animal's general health is unaffected.

  • Head bobbing
  • Limb tremors
    • Aggravated by movement or eating
    • Disappear during sleep
  • Unsteadiness or clumsiness with a wide-based stance
  • Unable to judge distance and disequilibrium:
    • Falling, flipping over
  • Slight improvement may occur as the puppy accommodates to its deficits


  • Infection of the body and/or brain
  • Environmental toxins, ingested toxins
  • Nutritional deficiencies

Intention tremor (of both head and limbs) is common. The tremors worsen with stress or excitement and subside when the dog is at rest. Diagnosis is based on the clinical signs, lack of progression, and lack of significant findings on other diagnostic tests

There is no treatment for this condition. Affected dogs will not get any worse (or better) and, especially where the signs are mild, may be able to lead a relatively normal life, particularly if owners can adjust their expectations to the dog's limitations.

Dependant on the severity, dogs affected will not be able to make decisions to protect thesmself as other dogs do. You will need to restrict your dog's activity and movement so as to prevent injuries and road accidents. Climbing, falling, or freedom of movement at the park, all of the normal things that dogs do, will need to be prevented with your dog. In the case of severely brain deficient animals that are unable to feed or groom themselves, or to be house trained, euthanasia may be considered.

Affected dogs, their parents and their siblings should not be used for breeding.