What Is Deafness in Dogs?
Deafness in dogs refers to the inability to hear, which can occur at any age and for various reasons, although it’s commonly associated with older dogs.
For mammals, including dogs, hearing relies on the precise transmission of sound waves through the inner and outer ear’s soft tissues and bony structures. If any of these components are compromised due to infection, trauma, or improper development, the pathway for sound transmission is disrupted, leading to an inability to perceive sound accurately.
Deafness in dogs can manifest as complete or partial loss of hearing, depending on the underlying cause.
Partial Deafness in Dogs
Identifying partial deafness in dogs can be challenging as they often compensate well for any hearing loss, experiencing it either in one ear or only at certain frequencies.
Partial deafness affecting both ears commonly arises from infectious or inflammatory conditions like ear infections (otitis externa). In such cases, there’s a higher likelihood of the pup recovering their hearing.
Although deafness itself isn’t an immediate medical emergency, it’s crucial to promptly address painful conditions like otitis and trauma, which can lead to deafness, through veterinary care. Persistent inflammation reduces the likelihood of your dog’s hearing fully recovering.
Symptoms
Here are common symptoms indicating deafness in dogs:
- Ignoring environmental sounds
- Trouble waking a sleeping dog
- Confusion regarding the origin of sounds
- Increased barking
- Alteration in the dog’s bark
- Absence of ear movement during communication
Causes
Congenital Defects:
Dogs may be born deaf (congenital deafness) due to inner ear defects, a common cause usually diagnosed in puppies older than four weeks.
Certain breeds like Dalmatians, Cocker Spaniels, Boston Terriers, Australian Cattle Dogs, and Parson Jack Russell Terriers, especially those with merle and white coats, are more prone to genes associated with improper cochlear development.
Maternal infections during pregnancy or exposure to toxins or medications can also lead to congenital deafness in puppies. Unfortunately, puppies born deaf do not regain their hearing.
Ear Infections:
Canine ear infections can affect the external, middle, or inner ear, causing varying degrees of hearing loss. External ear infections may narrow the ear canal, hindering sound wave entry, but typically do not cause complete deafness and often improve with treatment.
Middle ear infections (otitis media) can damage the eardrum and hearing bones, with recovery usually restoring hearing, though scarring may result. Inner ear infections can inflict irreversible nerve damage in the cochlea, leading to partial or complete, typically irreversible deafness.
Drug Toxicity:
Certain medications like cisplatin (a chemotherapy drug) and furosemide (used for heart failure) may cause permanent deafness in dogs, although not all dogs will fully lose their hearing.
Deafness from drug toxicity progresses over time with continued use, making it crucial to discuss risks and benefits with a veterinarian.
Systemic Illness:
Endocrine disorders like Cushing’s disease and hypothyroidism can increase the likelihood of deafness due to metabolic changes affecting blood flow and nerve function.
Cancer, whether primary or metastatic, can physically alter the ear or brain, leading to deafness. Nervous system infections such as meningitis and epilepsy can also impair the brain’s ability to process sound.
Trauma:
Physical trauma to the brain or auditory system can result in deafness. Aggressive ear cleaning or flushing can rupture the eardrum or cause inner ear inflammation, emphasizing the importance of following veterinarian instructions for ear care.
Noise-Induced Hearing Loss:
Repeated exposure to loud noises like gunshots can progressively lead to deafness, particularly in military or hunting dogs. Ear protection is available for at-risk working dogs.
Age:
Age-related hearing loss (presbycusis) is common in older dogs, resembling hearing loss in aging humans. It typically affects dogs later in life due to various factors including genetics, overall health, and lifestyle.
Diagnosis
Diagnosing deafness in dogs poses challenges for veterinarians.
Physical Examination:
While a physical exam may reveal visible issues such as external ear infections or masses, many causes of deafness remain invisible or not palpable, even with tools like an otoscope. Dogs’ responses to sounds in the exam room may vary due to excitement or anxiety, complicating diagnosis, especially in cases of partial deafness where the unaffected ear compensates for the loss.
A comprehensive history is crucial. Informing the vet about the duration of hearing loss, whether it’s sudden or progressive, and any relevant medical conditions or medications can guide further testing and treatment.
During the physical exam, the vet can directly assess the external ear canal and eardrum. However, evaluating the entire hearing system requires more than this examination. The vet will also evaluate your dog’s balance and other nerves in the head and neck, as loss of nerve function or balance alongside hearing loss may indicate issues in the inner ear or brain.
Diagnostic Testing:
In cases where the physical examination appears normal, baseline blood work and urinalysis help detect systemic illnesses like Cushing’s disease or thyroid disease, which can directly affect hearing.
Imaging plays a crucial role in diagnosis. While radiographs can rule out cancerous masses in the chest or abdomen, visualizing skull changes is challenging with two-dimensional images. CT scans are more effective in detecting inner ear trauma or otitis interna. MRI may be considered for suspected neurologic causes.
Given the myriad potential causes of deafness, the vet will help select appropriate diagnostics to pinpoint the underlying cause of the hearing issue in your dog.
Treatment
The treatment of deafness in dogs varies depending on its cause. In most cases involving issues with sound conduction—such as ear canal obstruction, minor eardrum damage, or middle ear infections—treatment is available and can lead to a restoration of hearing with proper care.
However, dogs with cochlear or nervous system damage, whether from birth or acquired, are less likely to regain their hearing. In such instances, the focus of treatment should be on ensuring the dog’s comfort and overall quality of life.
Living and Management
The recovery timeline for dogs expected to regain their hearing varies depending on the root cause of the condition.
Immediate improvement can often be observed after removing masses or debris from the ear canal, leading to a swift return to normal function. However, healing from otitis media or eardrum damage may take weeks, with gradual improvement as tissues heal and inflammation subsides. Whether the deafness is temporary or permanent, there are several strategies to assist your dog:
- Adjust your communication style since auditory commands will no longer be effective. Puppies born deaf can readily learn visual cues and hand signals, but older dogs may require some time to adapt.
- Gain and maintain your dog’s attention by stomping your feet on the floor as you approach. This helps prevent startling them when you interact.
- Due to their altered sensory perception, it’s advisable to keep deaf dogs indoors, in enclosed areas, or on a leash for safety. They may not hear approaching vehicles or cyclists and could be startled by strangers or other animals.
- Consider attaching patches to your dog’s harness to alert others to approach with caution. Medical alert tags are also available for this purpose.
Prevention
To prevent avoidable causes of deafness in your dog, promptly address suspected ear infections and collaborate with your veterinarian to manage allergies and other factors contributing to otitis externa.
Utilize ear cleaners recommended by your vet and refrain from using cotton swabs in the ear canals. Avoid administering ototoxic medications (those potentially harming hearing or the auditory system) at doses higher or longer than advised by your veterinarian.
Exercise caution with topical medications in the ear unless your dog has recently undergone examination. For working or hunting dogs exposed to gunfire or other loud sounds, consider using ear protection.
Deafness in Dogs FAQs
Can deaf dogs be happy?
Hearing loss itself isn’t inherently painful, and deaf dogs can lead fulfilling lives with adjustments made for safety and stress reduction.