Congenital Deafness in Dogs

Congenital deafness differs from hearing loss as congenital deafness is present either at birth or within the first few weeks after birth. Congenital deafness may be inherited or acquired by an illness such as toxic exposure, liver disease, the side effect of a drug, and infections. 

Some of the most commonly affected breeds are Dalmatians, Bull Terriers, Australian Cattle Dogs, English Setters, English Cocker Spaniels, Boston Terriers, and Parson Russell Terriers. 

Congenital deafness is present in over 100 different breeds but can affect any breed. Dogs with spotted, dappled, or merle coats and those with white skin or fur are predisposed to congenital deafness. The most commonly affected breed is the Dalmatian, with 30% of the breed suffering from some form of deafness.

This condition can be caused by a genetic defect such as those linked to multiple genes and gender, known as a recessive or autosomal dominant mutation. Experts say the most common cause of congenital deafness in dogs is related to pigment (the color of the coat). 

If your dog has congenital deafness, symptoms will present themselves within a few weeks after brith. That said, it may take a while to notice the deafness because the symptoms are not physically visible. Some of the most commonly reported symptoms of congenital deafness include:

• Aggressiveness when playing with other puppies
• Ignoring squeaky toys and other noisy toys
• No response to loud noises such as doorbells, barking, whistling, clapping, and yelling
• Abnormal amount of sleeping compared to other dogs
• Jumping or snapping when woken or touched when not looking
• Lack of activity
• Ignoring commands
• Unusual vocalizing
• Confusion and disorientation

Congenital deafness can be inherited or obtained. It is either cochleosaccular or neuroepithelial. Cochleosaccular congenital deafness is the most common, as it refers to dogs that a deaf genetically due to having the white, merle, or piebald gene. 

Dogs with any light-colored or white pigmentation of the skin or coat can be predisposed to deafness. The condition usually develops 1 to 3 weeks after birth when the stria vascularis in a dog's inner ear begins to deteriorate. This deterioration is caused by the dog's pigment gene suppressing melanocytes, a skin cell that contains the melanin pigment.  

Neuroepithelial deafness usually affects both ears and is less common than cochleosaccular deafness. Neuroepithelial deafness doesn't relate to pigmentation and instead is caused by hair cell loss that isn't related to the stria vascularis. Neuroepithelial deafness develops over a similar time period to cochleosaccular deafness. 

It's also possible for dogs to acquire congenital deafness. This form of congenital deafness is usually due to exposure to drug toxicity in utero. Many drugs can cause damage to the ear, including diuretics like furosemide and aminoglycoside antibiotics like gentamicin. Other conditions which can cause congenital deafness to puppies in utero include uterus infections, meningitis, and liver damage. 

If your dog's breed is at high risk of congenital deafness, it is important that you get them tested, whether you have noticed any symptoms or not. Recording this disorder in dogs is essential to the studying the disease and will help provide better treatment in the future.  

Your vet will begin with a complete physical assessment, checking your dog’s vital signs and body condition. There are also several tests that the veterinarian will do to rule out other conditions including blood tests, urinalysis, and x-rays or ultrasounds.

There is one test that can be used to definitively diagnose your dog, which is the brainstem auditory evoked response (BAER) test. A vet cannot give a dog a BAER test until after they are two weeks old as their ear canals are not yet open. 

This procedure is done by placing recording electrodes on your dog’s ears. Clicks are sounded into the ear through a headphone and the responses are then sent to an electro diagnostic machine that shows the waveforms of the ears. The results of this test are usually very effective and the veterinarian will be able to tell if your dog is able to hear. 

There is no treatment for congenital deafness in dogs. It can be prevented in some cases by not giving your dog any medication and getting regular checkups during pregnancy. You can use a vibrating collar to help with training your dog, if needed, or there are training classes for you and your dog to learn hand signals.

As your dog cannot hear cars or other dangers, it is best to keep them on a leash or in a fenced area while outside and keep a tag on his collar that says “Deaf” so others know he cannot hear them. Teaching your dog to follow hand signals is just as easy as training a dog that is not deaf. It just takes time and patience. Your veterinarian can help you find the right kind of training plan for you and your dog.

Congenital deafness can be expensive to diagnose. Start searching for pet insurance today from leading companies like PetPlan and Embrace to find the “pawfect” plan for your dog in just a few clicks!