Cerebellar hypoplasia

What is ... ?: 

The cerebellum is the part of the brain that regulates the control and coordination of movement. In this condition, the cells of the cerebellum do not mature normally before birth - this causes clinical signs related to poor balance and incoordination. It is most common in kittens that have been exposed to panleukopenia virus ( also called feline distemper) in utero. It is less common in dogs, where it may be related to in utero parvovirus infection. Some cases are believed to be inherited.

How is ... inherited?: 

Autosomal recessive. This disorder is rare. There are sporadic reports of this disorder in breeds other than those listed below.

What does ... mean to your dog & you?: 

The cerebellum is the part of the brain that regulates the control and coordination of voluntary movement. The clinical signs of cerebellar dysfunction in affected puppies range from mild to severe, and may include poor balance, a wide-based stance (feet planted far apart), stiff or high-stepping gait, apparent lack of awareness of where the feet are (standing or walking with a foot knuckled over), and head or body tremors. Affected pups 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.

How is ... diagnosed?: 

 The clinical signs (relating to uncoordinated movement and lack of balance) are evident as soon as the pups are walking and are suggestive of a cerebellar disorder. Your veterinarian will do tests to rule out other conditions that can cause similar signs.

How is ... treated?: 

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.

For the veterinarian: 

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.

Breeding advice: 

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



Jones B, Shiel R. Neurologic disorders. In: Shaer M, ed. Clinical Medicine of the Dog and Cat. London, UK:Manson, 2010: 644.
Coates, J.R. 1996. Weeble, wobble, roly, poly: a study of cerebellar disease. ACVIM-Proceedings of the 14th Annual Vet. Med. Forum. pp 684-687. This reference provides a comprehensive breed list, with associated clinical and pathologic findings.

What breeds are affected by ... ?