Cerebellar hypoplasia in cats is a condition that causes abnormal walking and tremors. It is one of the most common diagnoses of feline cerebellar disease. This condition can affect cats of all ages but is particularly common in kittens and young cats. The most common cause of cerebellar hypoplasia is infection with the feline panleukopenia virus, but it can also be caused by other insults to the developing cerebellum. Symptoms of cerebellar hypoplasia in cats can vary and depend on how much of the cerebellum is affected. For cats with mild symptoms, the prognosis is good but it takes a dedicated cat owner to care for these cats.

What is the cerebellum and what are its functions?

The cerebellum is a part of the brain located in the back of the skull. It plays an important role in balance, coordination, and muscle tone. The cerebellum controls movement by sending messages to the muscles telling them when and how to move. When these messages are not sent correctly or are sent too late, it can cause problems with movement and balance. Cerebellar hypoplasia is an incomplete development of the cerebellum.

cerebellar hypoplasia in cats

What causes cerebellar hypoplasia in cats?

Congenital cerebellar hypoplasia in cats is often the result of teratogenic in utero influences, such as viral infections, or may occur as the result of developmental defects. Cerebellar hypoplasia in cats can be caused by trauma, hypoxemia, and/or teratogenic toxins. The most common cause of cerebellar hypoplasia in cats is an in-utero infection of the feline panleukopenia virus. This virus is well known for infecting the cerebellum either in utero or during the neonatal period. When cerebellar hypoplasia is caused by the feline panleukopenia virus, infection occurs in utero via the transplacental route, or in the neonatal period via the feces-oral route. A cat that has been infected with the panleukopenia virus during its last 3 weeks of gestation, or a newborn cat that has been infected within the first 3 weeks of life, may develop cerebellar hypoplasia.

What are the symptoms of cerebellar hypoplasia in cats?

The clinical symptoms are present at birth and are not progressive. Affected cats may become smaller than their littermates due to difficulty nursing and clinical signs may vary in severity from mild to severe. Typical clinical symptoms of cerebellar hypoplasia in cats include:

  • Ataxia (lack of coordination)
  • Hypermetria (over-reaching or hyper-action of the limbs)
  • Fine tremors, especially of the head
  • Swaying of the body
  • Broad-based stance

How is cerebellar hypoplasia diagnosed in cats?

Age, clinical symptoms of cerebellar dysfunction, and a lack of progression are all used to make a diagnosis. Clinical signs are first noticeable when the affected cat first starts to walk, at around 3 weeks of age. The clinical signs of cerebellar hypoplasia in cats do not progress if there are no other defects. This differentiates the condition from degenerative and infectious conditions that progress. An MRI of the brain will show a cerebellum that is much smaller than normal, and there will be more cerebrospinal fluid (CSF) around it.

What is the treatment for cerebellar hypoplasia in cats?

Unfortunately, no specific treatment is available. To ensure the safety of affected cats, it is recommended that they be kept indoors. It may be helpful to provide large litter boxes with high sides and a low, wide entrance. Non-slip mats, especially in feeding areas, can be useful.

What is the prognosis for cats with cerebellar hypoplasia?

Quality of life varies with the severity of the condition. If only cerebellar hypoplasia is present, symptoms are not progressive. Signs persist normally throughout the cat's life but may improve as the cat learns to compensate.

How can cerebellar hypoplasia be prevented in cats?

It is important to prevent in-utero and neonatal infections in cats by vaccinating against the feline panleukopenia virus, particularly before breeding. Modified-live panleukopenia virus vaccines are not recommended in cats that are pregnant.


Cerebellar hypoplasia is a neurological condition in cats that causes ataxia, which is an inability to coordinate muscle movements. The cerebellum controls movement by sending messages to the muscles telling them when and how to move. When these messages are not sent correctly or are sent too late, it can cause problems with movement and balance. Cerebellar hypoplasia in cats can be caused by trauma, hypoxemia, teratogenic toxins, or viral infections such as feline panleukopenia virus (FPV). If your cat displays any of these symptoms consult your veterinarian immediately!