What Is BAER Testing in Dogs and How Does It Work?

Hearing loss in dogs is more common than many owners realise, and confirming whether a dog can hear — and to what degree — requires a specialised diagnostic procedure. BAER testing in dogs (Brainstem Auditory Evoked Response testing) is the definitive, non-invasive dog deafness test used by veterinary neurologists to objectively assess hearing function in one or both ears. Unlike behavioural hearing tests, the BAER test for dogs does not depend on the animal’s cooperation or attention, making it reliable across all breeds, temperaments, and ages.

Understanding how BAER testing works, which dogs should be tested, and how to interpret the results helps breeders, owners, and veterinarians make informed decisions about hearing-impaired animals’ care and management.

How the BAER Test for Dogs Works

The Brainstem Auditory Evoked Response test measures the electrical activity generated in the auditory pathway — from the cochlea through the brainstem — in response to a series of brief click sounds. Small electrodes are placed on the scalp (vertex), behind each ear, and on a reference point, typically the neck. Clicks are delivered through foam insert earphones, one ear at a time, while the contralateral ear is masked with white noise.

The resulting waveform — a characteristic series of five waves — is displayed on a computer screen and assessed by the veterinary neurologist. Each wave corresponds to a specific anatomical structure in the auditory pathway. Absent or abnormal waveforms indicate deafness or neurological auditory pathway dysfunction. The test takes approximately 10 to 20 minutes and is performed while the dog is relaxed or lightly sedated.

Which Dogs Should Have BAER Testing?

Breeds with Hereditary Deafness Risk

BAER testing is a standard recommendation for breeds with documented hereditary congenital deafness, including Dalmatians, Bull Terriers, English Setters, Australian Cattle Dogs, Boxers, and Catahoula Leopard Dogs. In Dalmatians, congenital deafness affects approximately 8 percent of puppies unilaterally and 2.5 percent bilaterally. Unilateral deafness is invisible behaviourally without testing — affected dogs compensate so effectively that owners and breeders frequently have no idea one ear is non-functional.

Breeding Animals

Responsible breeders test all animals before breeding, as deafness in some breeds has a documented hereditary component linked to pigmentation genetics. Knowing the hearing status of breeding animals allows informed selection and prevents the propagation of deafness within breeding lines.

Dogs Failing Behavioural Hearing Tests

If you are wondering how to test if your dog is deaf using behavioural methods — clapping behind them, calling their name, jingling keys — note that these methods are unreliable. Dogs with unilateral deafness pass behavioural tests consistently. Only BAER testing definitively confirms or rules out deafness in one or both ears.

Dogs with Acquired Hearing Loss

BAER testing is also valuable for dogs suspected of developing acquired deafness due to chronic ear infections, ototoxic drug exposure, noise trauma, or age-related degenerative changes. Serial BAER testing over time can monitor hearing function and document progressive change.

What the Results Mean

BAER test results are classified as normal, unilaterally deaf, or bilaterally deaf. Normal results show the characteristic five-wave pattern bilaterally at normal threshold levels. Absent waveforms in one ear indicate unilateral deafness (BAER negative, unilateral). Absent waveforms in both ears indicate complete bilateral deafness.

Partial or atypical waveforms may indicate partial hearing loss or neurological auditory pathway abnormalities requiring further evaluation.

Living With a Deaf Dog

Bilaterally deaf dogs can live full, happy lives with appropriate management adjustments. Training through hand signals, maintaining visual contact, using vibration-based waking (gentle touch) rather than auditory cues, and ensuring safe, enclosed exercise areas are practical adaptations that deaf dogs’ owners master quickly.

Conclusion

BAER testing in dogs is the only reliable, objective method for confirming hearing status in both ears. For at-risk breeds, breeding animals, and any dog whose hearing is in question, a BAER test provides definitive, documented results that support informed care decisions. If you suspect your dog may have a hearing deficit, specialist neurological BAER testing is the appropriate next step.