Of course, I knew that all puppies are born blind and deaf. Their ear canals are closed, and normally begin to open at 12-16 days of age. But with deaf puppies, a group of nerve cells in the ear that detect sound begin to deteriorate. This process is usually complete by the time the pup is 6 weeks old, and cannot be reversed or corrected.

But why does this happen?

The answer to this question lies in, you guessed it, genetics. Genetics, the wondrous mixing and matching of DNA that tell a Poodle's coat to curl and a Basset's ears to droop. Wonderful, mysterious genetics.

I can already hear you groaning. But if you read on, I promise to make this as painless as possible. I promise you'll learn something. And who knows, you might even enjoy it.

Before we dive head first into the gene pool, we need to keep a couple of guidelines in mind. First, I’m not a scientist, so I’m not going to be discussing which genes are dominate, probable outcomes of various breeding combinations, and so forth. The intent of this article is to give an overview, in layman’s terms, of the different types of canine deafness. Secondly, at the end of this article is a list of 68 breeds which report problems with hereditary deafness (i.e., pups born with hearing loss). There have not been extended studies performed on all of these breeds. The largest body of research has been done on Dalmatians, and breeds which carry piebald genes. Additional studies on Pointers and Dobermans have found deafness caused by other genes. Third, dogs can lose their hearing due to ear infections, injury, exposure to loud noise, and so on. This article discusses dogs who are born deaf due to genetic (inherited) reasons. Finally, although we may know the name of the genes involved, scientists are still unclear on how these genes are transmitted.

When it comes to figuring out which genes create deafness, one size does NOT fit all. Genetically speaking (and we are), there are four different types of genetic occurrences that can cause a puppy to be born deaf. So let's talk about these genes, using as few big words as possible.

The first occurrence involves the piebald and/or extreme piebald genes. These are pigmentation genes, meaning they help determine a dog’s coat color. The red flag here is white coat color. In effected breeds, a dog with large amounts of white in it's coat, and especially on it's head, is more likely to be deaf than it's more colorful littermate. I say "more likely" because it's still unclear exactly how these genes are transmitted.

To further complicate things, not all breeds which carry these genes report hereditary deafness. If you look at the list of effected breeds, you’ll notice that the Samoyed isn’t on it. (The Samoyed is an all white dog.) Therefore, it’s not accurate to say that only white dogs have problems with hereditary deafness.

Effected pups can have partial or total hearing loss. I haven’t found any studies that show a link between piebald genetic deafness and additional health problems (other than problems normally experienced by a particular breed). Rather, they are healthy dogs who can't hear. Examples of effected breeds are Dalmatians, Boxers, and Jack Russell Terriers.

involves piebald or extreme piebald genes

in effected breeds, predominately white dogs are more likely to be deaf

causes partial and total deafness

no additional health problems in effected dogs

Still with me? Good. The second occurrence involves the merle genes, specifically the homozygous merle gene. The merle (or dappled) gene creates a highly desirable coat color which is a patchwork of light and dark areas. Trouble arises when two dogs with the merle coat/gene are bred. In such a breeding, 25% of the offspring may inherit the homozygous merle gene. These homozygous merle pups are also called "double merle" or "lethal white" pups.

Again, predominately white coat color is a red flag. Double merle pups will have large amounts of white in their coats, but can also have some merle patches. In addition to being deaf, these pups may also be blind, partially blind, have severe organ problems, as well as allergy and skin problems. Some do not live long, hence the nickname "lethal white." Not all double merle pups have the full range of problems. Some may be deaf and suffer from allergies, or deaf with partial vision loss. As you can see, the double merle gene causes a wide range of health problems, in addition to deafness. Examples of effected breeds are Collies, Shetland Sheepdogs, and Harlequin Great Danes.

involves homozygous merle gene

predominately white dogs are more likely to be deaf

wide range of health problems seen in effected dogs

A third type of genetic deafness was discovered during a study on deafness in Pointers. Although Pointers do carry a piebald gene, it is believed that a recessive gene is the cause of deafness. Unlike the two above examples, this deafness is not linked to large amounts of white in the coat or on the head. It was reported that this gene only caused complete deafness, i.e., no pups were born with partial hearing loss. However, this study was done before BAER testing was available. Therefore, it’s possible that it does cause partial hearing loss. I’ve not been able to locate any follow-up studies. Effected dogs do not suffer from any additional health problems. Examples of effected breeds are Pointers, Whippets and Rottweilers.

involves recessive gene

not linked to white coat color

reported to only cause complete hearing loss

no additional health problems in effected dogs

A fourth type of genetic deafness was recently discovered during a study on deafness in Doberman Pinschers. Dobermans do not carry the merle or piebald genes. This deafness is thought to be caused by a simple autosomal recessive gene. Effected dogs also exhibit balance problems. They may walk with their head tilted, or walk in circles. This has also been reported in the Shropshire Terrier.

involves simple autosomal recessive gene

not linked to white coat color

effected dogs exhibit balance problems

It's important to be aware of the different characteristics of each genetic occurrence, and the breeds that are effected by them. Because dogs effected by the double merle gene have a wide range of health problems, there is a common belief that ALL deaf dogs have additional health problems. It's also widely believed that only white dogs can be born deaf. The above discussions show that neither of these beliefs is completely accurate.

With this basic understanding of the genetics involved in canine deafness, let's now turn our attention to something more practical. What can you do if you suspect that your dog is deaf?

It can be very difficult to figure out if a young puppy is deaf. As stated above, all pups are deaf and blind until 12-16 days of age. Once their eyes open, a deaf puppy will take visual clues from his hearing littermates. When the hearing puppies scramble after a toy, the deaf puppy follows along. Of course, the deaf puppy has to be awake and watching the other pups. Once he falls asleep, he enters a silent world. Therefore, one of the first indications of hearing loss is a puppy who doesn't wake up unless he is touched, or bumped, by another puppy. The hearing pups may lift their heads in response to a sound, while the deaf puppy continues to snooze. Anyone who's ever seen a litter of puppies knows that they live in constant contact with their brothers, sisters and mother. They sleep in an untidy heap, and bump, jostle and step on each other when awake. This can make it difficult to separate one pup's behavior from the behavior of the group as a whole.

As the old saying goes, "Mother knows best." Sometimes, the deaf puppy's mom will figure out that there’s something wrong with junior's ears. She may try to "fix" the problem by excessively licking and cleaning his ears. Dogs with normal hearing have also been know to exhibit this same behavior toward a deaf dog.

The deaf puppy's style of play may also be an important early clue to his deafness. Puppies learn to control the aggressiveness of their play based on feedback from other puppies. If a puppy bites too hard, the pup he is playing with will yelp from the pain. Through a series of trial and error, puppies learn to control the intensity of their bite. Obviously, the deaf puppy doesn't receive this valuable feedback. He may appear too aggressive during play, biting hard and not letting go when the other puppy cries in pain.

These same behavior patterns will become more obvious once the puppy leaves the litter, and joins his human family. The puppy will be difficult to rouse from sleep, and won't respond to loud noises while sleeping, or if the noise occurs behind him. He will contentedly snooze in the middle of the living room, unaware of an approaching vacuum cleaner. Or a knock on the front door. He won't respond to your voice if you are not in his line of sight, such as if you are in another room or behind him. Family members will now be on the receiving end of his rough style of play. He will bite hard on your hands or feet, and be unresponsive when you yell "OUCH!" or "No, bad puppy!"

If you suspect your new puppy or dog is deaf, there are some simple tests you can perform at home IF you keep the following facts in mind. First, it can be very difficult to determine if a dog is unilaterally (partially) deaf by using home testing methods. Unilaterally deaf dogs have little difficulty compensating for their partial hearing loss, although they may have some difficulty in locating the source of a sound. If a partially deaf dog is lying with his good ear pressed to the floor, you may notice that he doesn't hear or respond to sounds. The only way to be sure a dog is unilaterally deaf is to have him BAER tested. (The BAER test is described in further detail below).

Second, bilaterally (completely) deaf dogs are very sensitive to vibrations, movement, light, and air pressure changes. Vibrations include those that travel through the floor, as well as through the air. Be sure to keep these sensitivities in mind when devising and using a home test. The test will fail if the dog can feel a vibration, or sense air movement.

To test your dog, make sure he is not looking in your direction, or in the direction of the distraction you will be using. You can also try a test when your dog is asleep. With the dog in this position, stand behind him and try some of the following:

Jangle keys;

Squeak a squeaky toy (be sure that air from the toy doesnŐt hit the dog);

Call your dog in a normal voice;

Clap your hands (you should be far enough away so that he doesnŐt feel air movement);

Whistle;

Turn on a vacuum cleaner (be sure itŐs far enough away from the dog so that the vibrations donŐt reach him);

Bang two pots together (be careful of air vibrations reaching your dog);

Ring a bell.

You can also try yelling loudly, or blowing a whistle, if you keep the following caveats in mind. Some deaf dogs seem to hear very loud, or very low, noises. They may perk up, look around and have an expression on their face that says ŇWhat was that?Ó However, the dog usually doesnŐt orient to the source of the sound, i.e., if you are in front of your dog and yell ŇHEY!,Ó he may turn around and look behind him. Or he may look around the room. ItŐs almost as if they sense the sound, rather than hear it. Remember, not all deaf dogs exhibit this behavior.

If your dog doesnŐt respond to your tests, or you have any concerns about his hearing, you should have him examined by a veterinarian.

BAER Testing: BAER stands for Brainstem Auditory Evoked Response (pronounced ŇbearÓ). This is a procedure using computers to record electrical activity from the brain in response to sound stimulation. A clicking sound is directed into the ear with a foam insert, earphones, or headphones. Each ear is tested individually, and the test generally lasts for 10-15 minutes.

The BAER test is reliable, accurate, and the final answer to the question Ňis my dog deaf?Ó Or Ňis my dog partially deaf?Ó Pups can be tested at six weeks of age and older. The test is not painful, but many dogs donŐt like being restrained, or having wires hanging from their faces. Usually sedation is not necessary to perform the test. BAER testing is performed at select facilities around the country. For further information on BAER testing visit Dr. George StrainŐs web page, at http://www.lsu.edu/guests/senate/public_htlm/deaf.htm

For a variety of reasons, many deaf dog owners never have their dogs BAER tested. The test can be expensive, and many people do not live near a testing facility. Others simply donŐt want to subject their dogs to the experience. They are confident their dog is deaf based on their own experiences, and the assessment of their veterinarian. Those who do decide to have their dog tested may do so for their own peace of mind, because they simply must know for sure that their dog is deaf. Breeders of dogs at a high risk for congenital deafness (such as Dalmatians) may elect to have their puppies tested before placing them in homes.

* The next article will discuss common myths and misinformation about deaf dogs.

[Bold = relatively high prevalence]

RESOURCES FOR DEAF DOG OWNERS AND RESCUE GROUPS

The Deaf Dog Mailing List and Web Page

Deaf Dog Education Action Fund (DDEAF)

"Living with a Deaf Dog" by Susan Cope Becker

The Deaf Dog FAQ

Deafness in Dogs and Cats Website

Schools and Animal Sanctuaries

Deaf Dog Success Stories

Kali, My First Deaf Dog

By Leslie L. Judkins

Kali was one year old when she joined our family. She had spent the first year of her life with people who neglected and abused her. They didn’t realize she was completely deaf. They thought she was stupid, and tried to beat her into obeying. When that didn’t work, they asked a neighbor for training help. After a few minutes, the neighbor realized Kali was deaf. And just that fast, Kali needed a new home.

She was standing next to my husband when I walked into the house. I was wearing an over-coat and carrying my brief case. Kali looked at me like I was from another planet. She approached me slowly, with a look on her face that said "I don’t know about you." She gingerly sniffed my hand. Her nub of a tail began to wag. She started licking my hand while her body twisted into a "U" shape. I was enchanted. My husband said, "Doesn’t she have a great face?"

At 2:00 a.m., I was awakened by a loud crash. Kali had been sleeping on a blanket beside our bed. Apparently, she woke up and, disoriented by the strangeness of our room, crashed into a chair at the far end of the bedroom. I groped toward her in the darkness, in that instinctive way that mothers migrate to a child’s cry in the middle of the night. Every inch of her body was shaking. I held her until she relaxed, then gently guided her back to the blanket.

The next few months were difficult. Unbelievably difficult. Kali suffered from extreme separation anxiety. When left at home, she destroyed things. The companionship of our first dog, Sara, didn’t help. In fact the two dogs clashed, adding further tension to the situation. This tension climaxed in a fight between the two dogs which occurred when no one was at home. The dogs were kept in separate yards, but somehow both ended up in the garage. My husband returned home to a horrific scene. Both dogs were injured, but Sara was by far the most serious. Feeling we had reached the end of our rope, we called Boxer Rescue. And just that fast, Kali was gone.

The next two days were horrible. Sara had a puncture wound in her jaw and could barely open her mouth. We fed her medication, water and baby food with a syringe. We were sick with grief and guilt over the loss of Kali. We had screwed up, had failed horribly. And what would become of Kali?

My memory of those days is a blur. I went to work. I comforted my daughter, and tended to Sara’s injuries. And I prayed for Kali. I prayed that she wouldn’t become a throw away dog. I prayed that she would be placed quickly in the home that would be best for her. The place where she was destined to live. I prayed that she would be happy, and loved, and forgive us for failing her.

I was sitting in my office when the phone rang. It was Boxer Rescue. Kali had been temporarily housed at a vet clinic, where she had been spayed. She had recovered from surgery and was ready to leave, but no foster homes were available. Could we keep her, or board her, until a foster home became available? I hung up the phone and called my husband. We couldn’t stand the though of putting her in a kennel. And we couldn’t bring her home and give her up a second time. "I want to do the right thing," I said. And so Kali came home.

But not to the same naive family. Boxer Rescue gave me a mini "Boxer education." They told us about crate training and referred us to a trainer. We learned about the Boxer personality. I began reading about training, pack behavior, canine body language, adolescent dogs and dealing with separation anxiety. I took Kali to obedience school. I talked to trainers. Mostly importantly, I joined the Deaf Dogs mailing list and found that we were not alone.

I came to see how our ignorance had contributed to the problems we had with Kali. You can’t just bring a dog home because you feel sorry for them, or because they have a great face. Loving them, in and of itself, isn’t enough. You have to educate yourself about the nature of your breed and the ways of dogs.

Owning a deaf dog brings extra responsibilities as well. You can’t rely on your voice to control your dog. You must tune in to the world of movement, vibration and scent, then learn to use these things to communicate with your dog. When you walk into the kitchen and find your dog in the garbage can, you can’t say "No! Bad dog! Get out of there! " So you learn to stomp your foot hard enough to vibrate the floor. And when your dog turns around, she sees your scowling face, and you SIGN "No! Bad dog! Get out of there!"

When your dog’s nose is headed straight for a glass on the coffee table, you can’t say "Leave it!," and stop that nose before it arrives. Instead you use a traffic cop "STOP" hand signal. You learn that the energy you put into the sign seems to travel across the room to your dog. And she feels it, and stops.

Most importantly, you learn that DEAF doesn’t equal DUMB. Deaf dogs are only limited by the perceptions of their owner.

I laugh when I read about those who think deaf dogs are aggressive and untrustworthy. They should see Kali at my daughter’s school. She’s a celebrity! We stand there as the school bell rings. The kids pour from the classroom toward us, and Kali is surrounded by a sea of love. Their little hands sign her name, pat her wrinkled head, rub her floppy ears and touch her nub of a tail. Some kneel and, throwing their arms around her neck, are rewarded with a sloppy Boxer kiss. No startling, no snapping, no aggression. Just a wiggly white Boxer being loved by some kids.

Kali with Marissa & Conner

It’s been 2 years since Kali came into our lives. Despite the rough start, she is a happy, valued member of our family. In March of 1998, she became an AKC certified Canine Good Citizen (CGC). She has learned over 25 different hand signals, and the number is climbing. We know each other now and can communicate with a look. I no longer work outside my home, and Kali is my constant companion. Each day we have walks, car rides, training and play time. Each night she sleeps by my bed. I think back on the events that brought us together, and the people who helped along the way, and I feel lucky. I am touched by a sense of awe and wonder when I think about Kali’s capacity to forgive and love. My hope is that as we rush to embrace the "perfect dog", we’ll also reserve a small place in our hearts for the less than perfect ones. They too can be a special treasure, and enrich your life in immeasurable ways if you give them the chance. Kali taught me that.  Contact Leslie here  ljudkins@ix.netcom.com

Articles written exclusively for Critter Chat Newsletter, Copyright Leslie L. Judkins © 1998  Please feel free to link to us.

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