Cerebellar Ataxia in Dogs: Causes, Heredity & Testing Guide

Cerebellar ataxia (CA) is a neurological disorder affecting dogs, notably prevalent in the Italian Spinone and recently reported in some Hungarian Vizslas. It causes uncoordinated movements due to damage or dysfunction in the cerebellum, the brain region responsible for coordinating balance and movement.

Symptoms often start when puppies begin walking, with affected pups showing poor coordination, tripping over their feet, falling, leaning on furniture for support, and sometimes dragging their hind limbs. Early signs can be subtle as puppies are naturally clumsy, but in CA, symptoms worsen progressively.

By eight to ten months, clinical signs become pronounced, including exaggerated limb movements, tremors, a wide stance, abnormal eye movements, and balance loss. Sadly, CA is progressive and fatal, with affected dogs rarely surviving past their first year.

Understanding the Heredity of Cerebellar Ataxia

In breeds like the Italian Spinone, cerebellar ataxia is inherited autosomal recessively, meaning a pup must inherit two copies of the mutated gene—one from each parent—to be affected.

• Clear dogs: carry two normal copies of the gene and do not have CA nor pass it on.
• Carriers: carry one mutated copy but are clinically healthy; they can pass CA genes to offspring.
• Affected dogs: carry two mutated copies and develop clinical symptoms.

The inherited patterns mean that matings between carriers or affected dogs can produce litters with affected pups. For example:

• Two clear dogs produce only clear pups.
• Two carriers produce 25% affected, 50% carriers, and 25% clear pups.
• A clear dog bred to an affected dog produces 100% carriers.

Diagnosis and Testing for CA

Early identification is vital, especially for breeders aiming to maintain healthy litters and safeguard the breed's future. Puppy buyers under reputable schemes such as The Kennel Club’s Assured Breeder often request evidence of health screening for CA.

Testing involves collecting a DNA sample via blood or buccal swab, which a vet sends to approved laboratories for genetic analysis. Knowing your dog's status guides responsible breeding decisions to avoid producing affected puppies.

Supporting an Affected Dog

Currently, no cure exists for hereditary cerebellar ataxia. Management focuses on supportive care, ensuring the dog’s comfort and safety. Due to the progressive nature of the disease, affected dogs have limited mobility and a shortened lifespan.

Owners and breeders alike should prioritise responsible breeding practices by genetic testing their dogs and selecting mates accordingly. This prevents spreading CA and improves overall breed health.

Conclusion

Cerebellar ataxia is a serious hereditary neurological condition primarily impacting the Italian Spinone and occasionally other breeds such as Hungarian Vizslas. Understanding its symptoms, heredity, and testing helps dog owners and breeders take responsible steps to prevent affected litters.

If you plan to breed or purchase an Italian Spinone or related breed, always request proof of genetic testing for cerebellar ataxia from reputable breeders. Early diagnosis and responsible breeding are crucial for healthier puppies and safeguarding breed welfare.