If your older dog seems to ignore you when you call or no longer responds to squeaky toys or hand claps, she may be losing her hearing. Hearing loss, which ranges from partial hearing loss to total deafness, affects dogs of any age. Hearing loss can occur gradually or suddenly, but pet owners usually don't notice the problem until it begins to affect their dog's behavior.
Risk factors and detection
Just like people, dogs can be born deaf, which is known as congenital deafness, or they can lose their hearing over time, which is called acquired deafness. Congenital deafness is evident at a young age and affects more than 40 dog breeds. Dalmatians and dogs with predominantly white coats or merle coats (dark blotches or spots on a lighter background) are prone to congenital deafness.
Acquired deafness can affect dogs of any breed and age, but it's most common in older dogs. Factors that increase the risk of deafness include chronic ear inflammation or infection, the use of certain drugs (such as aminoglycoside antibiotics and chlorhexidine antiseptic solution), eardrum rupture, blockage of the ear canal from scarring and wax buildup, heavy metal poisoning (from arsenic, lead, or mercury), canine distemper, nervous system disorders, anatomic deformities, cancer, inflammatory or infectious diseases, and head trauma.
Gradual hearing loss or deafness in one ear (unilateral deafness) is difficult to detect because dogs change their behavior to compensate for the partial hearing loss. There are, however, some telltale signs.
Your dog may suffer from hearing loss if she:
- fails to respond to her name, strange noises, squeaky toys, or the can opener
- sleeps through loud noises
- startles when touched
- appears less active
- acts apprehensive when placed in a new location, especially if she also suffers from vision loss.
If you suspect hearing loss, check your dog's ears for evidence of inflammation or infection. A normal ear harbors only a small amount of light brown, odorless earwax and isn't red or painful. Excessive wax, redness, odor, pain, shaking of the head, or scratching at the ears can indicate inflammation or infection. If your dog's ears are not red or painful, you can clean the earwax out at home. Squirt a pet ear-cleaning solution into both ear canals and massage the base of the ear to loosen dirt and wax. Use cotton balls to remove loosened wax—cotton swabs can push debris farther into the ear canal.
Take your dog to the veterinarian if she shows signs of deafness or symptoms of an ear infection. The doctor will perform a complete physical examination and collect samples from your dog's ear for bacterial culture. He or she may also collect a blood sample to evaluate thyroid hormone levels. X-rays will help evaluate the skull, middle ear, and ear canals, and an ultrasound examination will detect anatomic abnormalities. If your dog's ears are painful, the doctor may sedate her prior to the exam. Be sure to tell the doctor if you have recently applied a topical medication or cleaner to your dog's ears.
In some cases, your veterinarian may refer you to an institution that performs the hearing test known as a brainstem auditory evoked response (BAER) test. This test objectively assesses hearing and can help diagnose unilateral deafness. Breeders also use the BAER test to identify and rule out affected animals—especially in breeds with a high incidence of congenital deafness.
The Institute for Genetic Disease Control in Animals maintains an open registry for inherited deafness to help breeders minimize the chances of passing on congenital deafness.
Prevention and treatment
The best way to keep your dog's hearing in tiptop shape is to keep her body in tiptop shape—especially her ear canals. Your pet's sense of hearing is better than yours, so limit her exposure to continual loud noises.
There is no treatment for congenital deafness, and treatment for acquired deafness is aimed at eliminating the cause. Doing so may prevent additional hearing loss and, in some cases, restore hearing. Treatment may include medical or surgical treatment for ear infections and discontinuation of any drugs that cause deafness, such as ototoxic drugs.
Treatment can't restore gradual hearing loss. But you can compensate for the hearing loss at home by using hand signals or stomping the floor to get your dog's attention—she will feel the vibrations. Make sure her environment is safe since she won't hear dangers, such as cars or other animals.
Prognosis
With a few accommodations, deaf dogs lead long, happy lives. Keep these dogs indoors or safely fenced in the yard, and educate children and visitors about the dog's condition so they'll act accordingly (like not sneaking up on the dog when she's resting).
You can train deaf puppies with hand signals and sign language commands. This can be a difficult, though rewarding, process. And you'll probably need the help of veterinarian or trainer with experience training deaf dogs.
If a progressive, aggressive disease, such as cancer, is causing the deafness, the long-term prognosis is poor. Fortunately, this form of deafness is uncommon.
