The scenario shows up in breeder groups several times a month: a four-week-old puppy isn't responding to sounds the way the littermates are. The owner's first reaction is usually to wait and see. That's the wrong reaction. By four weeks of age, a normal puppy's hearing is essentially fully developed, and a puppy that consistently doesn't respond to sound is very likely deaf in at least one ear.
Congenital deafness in dogs is well-studied, well-understood, and — in the highest-risk breeds — surprisingly common. This guide covers what normal puppy hearing development looks like week by week, how to run a structured home check, when and why to BAER test, which breeds carry the most risk, and how responsible breeders handle deaf puppies and breeding-decision implications.
of Dalmatians are affected by some deafness
Roughly 22% unilateral and 8% bilateral — the most-cited congenital deafness statistic in dogs (Strain 2004)
When puppies actually start hearing
Puppies are born with their external ear canals completely closed. There is no functional hearing at birth and through the first week of life. This is normal and identical across all healthy puppies of all breeds — a one-week-old that doesn't startle to a loud noise is not a red flag.
The standard development timeline, sourced from classical canine neonatology (Merck Veterinary Manual; BSAVA Manual of Canine and Feline Reproduction and Neonatology):
| Age | Ear Canal Status | What You Should See | Red Flag? |
|---|---|---|---|
| Days 0–7 | Closed (sealed) | No response to sound. Puppy responds to touch, smell, and warmth only. | No — entirely normal |
| Days 10–14 | Opening | Ear canals progressively open. Puppy may startle inconsistently to very loud sounds. | No |
| Days 14–21 | Open, maturing | Startle reflex to claps and sharp sounds becomes more consistent. Puppy turns head toward sustained noises. | Lack of any response by day 21 is worth noting |
| Days 21–28 | Functionally mature | Reliable startle to sounds from any direction. Responds to littermates' vocalizations and the dam's movements. | Lack of response by 3 weeks is a genuine concern |
| Day 28+ | Fully developed | Responds reliably to conversational tones, food prep sounds, footsteps. Wakes from sleep at loud noises. | Definite concern — pursue BAER testing |
Hearing development timeline based on Merck Vet Manual and BSAVA Manual of Canine and Feline Reproduction and Neonatology. Individual puppies vary by 1–3 days; the patterns above describe the typical range.
By 4 weeks of age, a healthy puppy should respond reliably to sound. The most common search prompt — "my 4-week-old puppy can't hear" — is the moment many breeders first notice the problem, and it's a legitimate moment to act.
The home check that experienced breeders use
Before scheduling a BAER test, run a structured home check. Done correctly, this catches the majority of bilaterally deaf puppies and flags unilateral deafness in many cases. Done sloppily, it produces false reassurance.
- Wait until the puppy is awake but settled — not actively nursing, eating, or playing.
- Position yourself behind and out of sight of the puppy, far enough back that vibration through the floor or air movement won't reach the puppy first.
- Use a sharp, unexpected sound: a single hand clap, keys jangled once, or — the breeder favorite — a hardcover book dropped flat onto a hardwood or tile floor from about three feet up.
- A normal puppy will startle, twitch the ears, or briefly turn the head. The reaction may be subtle but it is unmistakable.
- Test each puppy individually. Test from both the left and right side, and behind. Test multiple times, several minutes apart, over a couple of days.
- If a puppy responds to some sounds but not others, or only to sounds from one side, suspect unilateral deafness — that is a BAER referral, not a clean bill of health.
The structured home check has real limitations. Puppies are visually attentive and may follow your gaze, or sense vibration through the floor, or respond to a sibling's reaction rather than the sound itself. This is why unilateral deafness — where one ear works and one does not — is so easy to miss. A puppy with one good ear behaves almost normally; it just responds slightly later or seems "a little less attentive." The only way to catch unilateral deafness reliably is BAER.
Why congenital deafness happens — the pigment biology
The vast majority of congenital deafness in dogs is sensorineural — meaning it originates in the inner ear (the cochlea) rather than in the outer or middle ear. The mechanism, established by decades of research most associated with George M. Strain at Louisiana State University, comes down to pigment cells.
Inside the cochlea sits a tissue layer called the stria vascularis, which maintains the chemical environment the inner-ear hair cells need to function. The stria vascularis is rich in melanocytes — the same pigment-producing cells that color the coat, skin, and irises. When the pigment cells are absent from this tissue, the chemical environment inside the cochlea breaks down, and the sensory hair cells die off in the first few weeks of life.
This is why deafness in dogs is so strongly correlated with coat color genetics. The puppy is born with normal cochlear hair cells, but without melanocytes those cells degenerate before hearing fully develops — which is also why a deaf puppy often passes the casual newborn observation and only seems "off" at three to four weeks.
The two coat-color genes most implicated:
- The Merle (M) locus — heterozygous merle dogs (Mm) have somewhat elevated deafness risk. Homozygous merle dogs (MM, often called "double merle"), produced when two merle parents are bred together, have very high rates of deafness — frequently exceeding 85% in well-documented studies — plus elevated rates of blindness and other developmental abnormalities. Merle-to-merle breeding is condemned by every major breed parent club in merle-eligible breeds (Australian Shepherds, Border Collies, Catahoulas, Great Danes, Shetland Sheepdogs, Dachshunds, Cardigan Welsh Corgis, etc.).
- The Piebald / Extreme White Spotting (S) locus — dogs with extensive white coats, particularly those with little or no pigment around the ears, have elevated congenital deafness rates. The Dalmatian is the most famous example, but Bull Terriers, Boxers, English Setters, English Cocker Spaniels, and several other breeds are affected.
Blue eyes in some breeds are also a deafness risk marker, because iris pigment cells share developmental origin with cochlear melanocytes. Strain's 2004 prevalence study found that Dalmatians with one or two blue eyes had significantly higher deafness rates than brown-eyed Dalmatians.
Breeds at the highest risk
Prevalence figures below are drawn primarily from Strain's body of work at LSU (Veterinary Journal 2004; Frontiers in Veterinary Science 2015) and from individual breed-research papers. Numbers vary by population and study — these are representative ranges, not fixed values.
| Breed | Bilateral (deaf both ears) | Unilateral (deaf one ear) | Notes |
|---|---|---|---|
| Dalmatian | ~8% | ~22% | The most-studied breed for congenital deafness. ~30% of all Dalmatians have some hearing impairment. |
| Australian Cattle Dog | ~3% | ~14% | High white spotting + merle interaction. |
| English Setter | ~4% | ~8.5% | Piebald-associated. |
| English Cocker Spaniel | ~2% | ~6% | Particles and parti-colors at higher risk. |
| Bull Terrier (white) | ~10% | ~10% | Colored Bull Terriers have much lower rates than white. |
| Boxer (white) | ~13% | ~5% | White and check-marked patterns highest risk. |
| Australian Shepherd | ~2.5% | ~3.5% | Much higher (>85%) in double-merle (MM) puppies. |
| Border Collie | ~2% | ~3% | Platt et al. 2006 — merle and white-headed dogs elevated. |
| Dogo Argentino | ~8% | ~7% | Extreme white phenotype. |
| Great Dane (harlequin/merle) | Elevated | Elevated | Specific to merle/harlequin patterns; solid colors much lower. |
| Jack Russell Terrier | ~1.5% | ~2.5% | Famula et al. 2007 — heritability documented. |
| Catahoula Leopard Dog | Elevated | Elevated | Glass-eyed (blue-eyed) and double-merle dogs highest risk. |
Prevalence ranges from Strain GM (Vet J 2004; Frontiers Vet Sci 2015), Platt et al. (J Vet Intern Med 2006), Famula et al. (BMC Vet Res 2007), and the LSU Deafness in Dogs and Cats database. Individual breeding lines may vary significantly from breed-wide averages.
BAER testing — the only definitive test
Brainstem Auditory Evoked Response (BAER) testing is the gold standard for diagnosing canine deafness. It is the test cited by the OFA, by every breed parent club, by veterinary teaching hospitals, and by the Merck Veterinary Manual. There is no other reliable substitute.
How a BAER test works
Small subcutaneous electrodes (about the gauge of an acupuncture needle) are placed at three points on the puppy's head — typically over the forehead, behind each ear, and on the back of the neck. A foam insert earphone is placed in one ear, then the other. The earphone delivers a series of clicks at known volumes. The electrodes pick up the electrical signal generated by the auditory nerve and brainstem in response to each click, and a computer averages thousands of these signals into a waveform. If the waveform shows characteristic peaks at the expected latencies, that ear hears. If the waveform is flat regardless of click volume, that ear is deaf.
The test takes 10–15 minutes per dog. Most puppies don't require sedation — the procedure is painless and the puppy can be gently restrained or held by the owner. Adult dogs or particularly wiggly puppies may receive light sedation. The result is available immediately at the end of the test, and ear-by-ear, so unilateral deafness is caught the same way as bilateral.
When to test
Most BAER testing centers will accept puppies starting at 5–6 weeks of age. Earlier than that, the auditory pathways aren't mature enough to give a reliable result. The standard breeder workflow is to BAER the entire litter at 6–8 weeks — well before placement, and typically combined with the first round of vet visits.
Where to get it done
BAER testing has become significantly more accessible than it was a decade ago. Active testing programs at U.S. veterinary teaching hospitals include LSU School of Veterinary Medicine (the original program, still active under Strain's ongoing work), Auburn University Scott-Ritchey Research Center, UC Davis Veterinary Medical Teaching Hospital, the University of Pennsylvania School of Veterinary Medicine, the Cornell University Hospital for Animals, and The Ohio State University Veterinary Medical Center. Many private veterinary specialty practices — neurology, internal medicine, or audiology — also offer BAER. The OFA BAER directory at offa.org maintains a list of registered providers searchable by state.
Costs in 2025 typically run $75–$150 per dog. Breed parent clubs occasionally arrange "BAER clinics" at national specialties where multiple dogs can be tested in one day at a reduced rate — these are a good option for breeders with several puppies or breeding-program dogs to clear.
Registering results with the OFA
The OFA (Orthopedic Foundation for Animals — orthopedicvet name notwithstanding, OFA maintains canine health databases for many systems beyond orthopedics) maintains a public BAER registry. After a BAER test, the testing veterinarian submits the result to OFA for a small fee, and the dog's status appears in the searchable public database. For breeding-program dogs, OFA-registered BAER results are the credible documentation breed clubs, judges, and buyers look for. For pet puppies, registration is optional but useful for breed health surveillance.
What to do if a puppy is deaf
A bilaterally deaf puppy is not a tragedy. It is a placement constraint and a breeding-program data point. Most well-managed deaf dogs live indistinguishably from hearing dogs to anyone but their owners.
Placement
Deaf puppies do best in households that:
- Have no off-leash unfenced access — a deaf dog cannot hear traffic, cannot hear recall, and cannot respond to sudden danger by sound.
- Have either no children or experienced older children who understand approaching a sleeping deaf dog from the front, with a gentle vibration through the floor or a hand wave in the dog's peripheral vision rather than a touch.
- Are willing to learn hand-signal training — most basic obedience cues can be taught using American Sign Language gestures or breeder-developed hand signals, and deaf dogs frequently excel at hand-signal communication.
- Understand that a deaf dog is generally not a candidate for breeding.
Most reputable breeders place bilaterally deaf puppies on spay/neuter contracts at a reduced or waived price, with full disclosure of the BAER result and the OFA registration number. The practice of representing unsold puppies as hearing when they are not is universally condemned and, in many states, may constitute civil fraud under puppy lemon laws.
Training
Deaf dog training is a well-developed discipline with extensive published resources. The Deaf Dog Education Action Fund (deafdogs.org) maintains a free library of hand-signal training guides and connects new owners with experienced trainers. Vibrating collars (vibration only — not shock) are used in some training programs as a non-aversive cue for "look at me" or recall at a distance. Recall is the hardest cue to install reliably; treat as a lifetime training priority.
Breeding-program implications
The published research and the breeding recommendations from every major affected-breed parent club point in the same direction: deafness should be selected against. Specifically:
- Bilaterally deaf dogs should not be bred. This is universal consensus across the literature and breed clubs.
- Unilaterally deaf dogs should not be bred in most breed-club recommendations, because unilateral deafness in a parent meaningfully elevates the deafness rate in offspring even though the dog functions normally. The Dalmatian Club of America, Australian Shepherd Club of America, and Bull Terrier Club of America all advise against breeding unilaterally deaf dogs.
- BAER-test every puppy in every litter in high-risk breeds before placement, not just the puppies a breeder suspects.
- Never breed merle to merle. This is non-negotiable. Genetic merle testing (the SILV gene) is widely available through laboratories like Embark, Wisdom Panel, Paw Print Genetics, and UC Davis VGL, and inexpensive enough that there is no excuse for a breeder not knowing the merle status of every breeding dog.
- Track deafness across pedigrees. If multiple littermates from a particular sire/dam combination test deaf, the combination should not be repeated, and the lineage data should inform future pairings.
Putting it together
A four-week-old puppy that doesn't respond to sound is not on a delayed timeline — it is a candidate for BAER testing. By 28 days of age the auditory system in a healthy puppy is functionally mature, and lack of response is a real signal, not a normal-variation curiosity.
The structured home check catches most bilaterally deaf puppies. It misses most unilaterally deaf puppies. In high-risk breeds — Dalmatians, Australian Cattle Dogs, white Boxers, white Bull Terriers, English Setters, double-merles in any breed — every puppy in every litter should be BAER-tested at 6–8 weeks before placement, regardless of whether the home check raised concern. BAER is the only test that reliably catches unilateral deafness, which is otherwise invisible until the dog is in a high-stakes situation where one ear matters.
Breeders working in affected breeds who want to dig deeper should also read health testing before breeding for context on how BAER fits alongside OFA hips, elbows, cardiac, and breed-specific DNA panels — and coat color genetics explained for the underlying merle and piebald inheritance mechanics that drive most deafness risk.
Frequently asked questions
At what age can puppies hear?
My 4-week-old puppy doesn't seem to hear — what should I do?
What is a BAER test?
How much does a BAER test cost?
When can a puppy be BAER tested?
Why does coat color affect deafness risk?
Can a deaf puppy still have a good life?
Should I breed a unilaterally deaf dog?
Is it ever okay to breed two merle dogs together?
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Sources: Strain GM. Deafness prevalence and pigmentation and gender associations in dog breeds at risk. The Veterinary Journal (2004) 167:23–32 — the foundational breed-prevalence paper. Strain GM. The Genetics of Deafness in Domestic Animals. Frontiers in Veterinary Science (2015) 2:29 — comprehensive modern review. Strain GM. Deafness in Dogs and Cats. CABI Publishing (2011). Cargill EJ, Famula TR, Strain GM, Murphy KE. Heritability and segregation analysis of deafness in U.S. Dalmatians. Genetics (2004) 166:1385–93. Famula TR, Cargill EJ, Strain GM. Heritability and complex segregation analysis of deafness in Jack Russell Terriers. BMC Veterinary Research (2007) 3:31. Platt S, Freeman J, di Stefani A, et al. Prevalence of unilateral and bilateral deafness in Border Collies and association with phenotype.Journal of Veterinary Internal Medicine (2006) 20:1355–62. LSU School of Veterinary Medicine — Deafness in Dogs and Cats project (lsuvetschool/deafness). OFA (Orthopedic Foundation for Animals) BAER registry — offa.org. Merck Veterinary Manual (Congenital and Inherited Deafness in Animals). BSAVA Manual of Canine and Feline Reproduction and Neonatology. AKC Canine Health Foundation. Deaf Dog Education Action Fund — deafdogs.org. This article is for educational purposes and does not replace professional veterinary care. Suspected hearing loss in any puppy warrants referral to a BAER testing center, and breeding decisions in high-risk breeds should be made in consultation with a reproductive veterinarian familiar with your breed's deafness genetics.