This is a neurologic condition, and has been reported in a number of breeds. It is an inherited disease and in many affected breeds signs appear in young puppies, however in a few breeds signs do not appear until they are several months old, or even when they are several years old. Abiotrophy literally means loss of vital nutritional substances, which are needed by the cell. A certain type of cell called the Purkinje cell in the cerebellum is affected by this disease, and the progressive loss of these cells means the cerebellum can no longer do its job properly.
The cerebellum is responsible for coordinating balance and movement, and the first signs are usually loss of balance, trouble cornering and falling over when shaking the head. Often affected animals will have a tremor that disappears when they are resting – this is often most noticeable in the head. The disease is slowly progressive, and eventually dogs cannot walk without falling repeatedly, or cannot rise to their feet. Some mildly affected animals may progress slowly and be able to be managed as house pets, however most dogs require euthanasia at some stage due to a deterioration of their condition to the point where their quality of life is unreasonably poor.
While the signs of cerebellar abiotrophy are similar in all breeds, the age of onset of signs and the rate at which the disease progresses do differ quite a lot from breed to breed. In some breeds, such as kelpies and Labrador retrievers, the disease is first seen in puppies 6 – 12 weeks of age, and progresses rapidly. In the Airedale, signs are seen at 6 – 12 weeks, but progresses slowly. In contrast to this, the disease is not seen in the American Staffordshire terrier until 3 – 5 years of age, and progresses over 2 – 4 years. In the Brittany spaniel, signs are not seen until around 10 years of age. In some breeds signs may stabilise at some point, with animals variably affected, but ambulatory and able to live a full life.
There is no treatment for this disease, and a genetic test is only available for a limited number of breeds. Diagnosis is based on breed, clinical signs and clinical progression. It can only be definitively diagnosed on post mortem examination (where there is no genetic test), and this can be important for breeding establishments. It is important to distinguish this disease from cerebellar hypoplasia, a developmental condition that causes similar signs but which is not progressive.