Oliver, my dog, and I recently visited a new groomer. His regular hairdresser was fully booked through the end of the month, so I thought I’d try one nearer to my workplace. Being a long-haired dachshund, I thoroughly shave him every year at this time. When it’s hot outside, he feels more comfortable, and the cut makes him look ten years younger. Win-win situation!
The groomer carried him outside and handed him to me when I arrived to pick him up. She had the expression one gets when they don’t know how to break bad news. I was a little perplexed by her face because Ollie looked fantastic and his little tail was wagging madly as though he had the time of his life.
She said, “Ollie is such a joy. I wish all dogs were this simple to groom. He is the sweetest man ever.
But her gracious remark didn’t seem to fit her expression, so I inquired, “So everything went well? Or is there a problem?
She looked down at Ollie with compassion and remarked, “I think Ollie might be deaf. ” Although it’s very typical for dogs his age, I felt you should be aware of it.
I said, “He is deaf and blind as well. I totally overlooked including that on the form. I apologize. To be honest, I frequently overlook the fact that he was born blind and deaf.
The wonderful thing about dogs is that. They can quickly make adjustments and compensate by using their other senses to find their way around. Actually, it’s pretty fantastic. In Ollie’s case, his sense of smell more than makes up for his deficiencies in vision and hearing.
He still enjoys playing with his chew toys, taking walks (ideally in straight lines without hitting any walls or cacti), and searching for treats that have been hidden around the house or office.
However, for the most part, he’s simply a fully regular dog that occasionally bumps into furniture and doesn’t come when you call him. It does occasionally occur to me that I have a dog with special needs.
Here’s an interesting fact: Dogs with primarily white coats can be more susceptible to hearing. True incident
What connection exists between hearing loss and a white coat? A unique layer of cells within the inner ear is responsible for hearing. The cells that determine hair color and this specialized layer both derive from the same stem cell source. Without this stem cell, the dog’s body won’t be able to produce this particular layer of hearing cells and will probably be colorless.
Dogs with the piebald gene frequently experience hearing loss. Piebaldism is caused by a lack of melanocytes, the cells that produce the melanin pigment. The DNA of a dog’s melanocytes is what determines its colour, such as whether it has brown or black hair or blue or brown eyes. (Blue eyes are not a true eye color; rather, they are the result of the iris’s lack of color-producing pigment.)
A dog with no melanocytes at birth has a predominately white coat (and frequently blue eyes). Bull Terriers, Boxers, English Setters, and Dalmatians are among of the breeds most frequently impacted by the piebald gene.
The merle gene, which gives a dog a merle (or dapple) coat and blue eyes, is also connected to congenital deafness. Breeds that are frequently impacted by the merle gene include Welsh corgis, border collies, dapple dachshunds, old English sheepdogs, and more.
Sookie, a 10-year-old white pit bull mix that lives in our shelter, was born deaf. She is not slowed down by it though.
She was a complete wallflower when she originally arrived to us in February. She first found being in the shelter to be frightening, so she never left her lair and resisted interacting with our staff and volunteers.
But one day, Quinn, one of our behavior specialists, was in the kennel with Sookie in the hopes that she would begin to relax and interact. Quinn figured she’d try to speak with her using a few simple signals since she also knew American Sign Language.
As soon as she started speaking to someone in this new area, Sookie perked up. She returned to being lively, engaging, and eager to interact with people right away. It was lovely. She is constantly picking up new signs and already knows “come,” “sit,” “go play,” “let’s go,” and “good girl.” She has won the affection of both staff and volunteers because of her remarkable ability to read signals.
What causes hearing loss in white dogs?
A unique layer of cells in the inner ear allows for the ability to listen. The stem cells that make up this layer and the cells that decide the color of a dog’s hair are from the same source. The body of the dog would likely be white without this stem cell and unable to develop this specific layer of auditory cells.
Dogs with the piebald gene, which changes the amount and distribution of white color, frequently experience deafness. Piebaldism results from a lack of melanocytes, the cells responsible for producing the pigment melanin. The melanocytes in a dog’s skin are what define its color, such as whether it has brown or black hair or blue or brown eyes (blue eyes are not a true eye color, but result from a lack of pigment that produces color inside the iris). A dog born without melanocytes has a coat that is primarily white (and often blue eyes). Breeds like Bull Terriers, Huskies, Boxers, English Setters, and Dalmatians are frequently afflicted by the piebald gene.
The merl gene, which results in a dog with blue eyes and a dog with mottled fur, is also connected to congenital deafness. Sheepdogs, Teckels, Corgis, and Border Collies are some of the breeds that are frequently impacted by the merl gene.
Is hearing loss more prevalent in white dogs?
The fact that the color of your dog’s fur indicates whether or not your dog will have normal hearing is one of the most important aspects connected to the coat color of dogs. George Strain of Louisiana State University in Baton Rouge, who has reported data on over 11,000 dogs using the Brainstem Auditory Evoked Response (BAER) test, which examines brain activity caused when sounds are registered by the ears, is arguably the most well-known researcher connected with this issue. He has been examining the risk factors for congenital deafness or hearing loss. Congenital hearing loss is one that is present from birth, albeit it can take weeks for a puppy’s breeder or doctor to notice it. Genetic factors, which are mostly responsible for congenital hearing loss, have been linked to particular coat colors. The following coat colors are most dangerously correlated:
- white
- piebald (much white with some spotting)
- roan (white or gray hairs mixed through the coat)
- merle (desaturated colors, especially where blacks become grays or blues)
The Dalmatian is the archetypal illustration of a piebald canine. A startling 30% of puppies in this breed are born with some sort of hearing impairment, with 22% having hearing loss in one ear and 8% having it in both. While all Dalmatians are essentially roan, certain members of other breeds carry the white, roan, or piebald gene while others do not. Individuals in the Bull Terrier, for instance, might either be white or have pronounced color patches. Congenital deafness affects white Bull Terriers at a rate of 20% while it affects animals with colored patches at a rate of only 1%. The parti-colored English Cocker Spaniels frequently have more white on them than the solid-colored canines, who have hardly any. Again, this is evident in their hearing capacity, with parti-colored dogs having a likelihood of being congenitally deaf that is more than twice as high. The data in the table below comes from Dr. Strain’s study.
The gene that makes a dog’s coat white also seems to increase the likelihood that the dog will have blue eyes. Therefore, it makes sense to assume that blue-eyed Dalmatians would have a higher likelihood of being deaf. This forecast comes true, and the result is rather striking. 51 percent, or roughly one in every two blue-eyed Dalmatians, had hearing loss in at least one ear. What’s worse is that even if the Dalmatian has brown eyes, his likelihood of being deaf increases dramatically if one of his parents had blue eyes. Based on data collected from Dalmatians in the United States, the table below depicts the association between a dog’s parents’ eye color and the rate of deafness in their offspring.
When do white dogs lose their hearing?
That was the first time I had ever heard about pigment-related deafness, as I now know it. Except for a website hosted by Dr. George M. Strain, a veterinary neurologist and biomedical researcher who is a recognized authority on pigment-related deafness, there wasn’t much information available online. So I contacted him for the information I required.
According to Strain, puppies born to parents that mostly have white coats or have a patchwork of different hues, like certain Australian shepherds, develop pigment-related deafness. Deafness is also strongly correlated with having blue eyes (either one or both).
Despite how unsettling it was to hear, Strain also had some welcome news for me. It turns out that deafness caused by pigment is not a threat to one’s life. According to Strain, crucial hearing-related cells are suppressed early, therefore deafness should be evident by the age of five weeks. We were no longer in danger because my dogs were just five months old (at least for that type of deafness).
Why do white animals lack hearing?
Inherited congenital (existing from birth) deafness in cats is nearly only observed in those with white coats. One ear (unilateral) or both ears may be affected by the deafness, which is brought on by the auditory apparatus of the inner ear degenerating (bilateral).
Breeding research have established a link between blue eyes and deafness in white cats. W is the name of the autosomal dominant gene that is to blame (for White). This gene, which is also responsible for the white coat color, blue eyes, and deafness, appears to be pleiotropic, meaning that it has several effects. However, while the gene has perfect penetrance for the color of the white coat (all cats carrying the gene will have white coats), it has incomplete penetrance for the color of the blue eyes and for deafness (but these two are strongly linked). As a result, deafness is highly associated with having a white coat and blue eyes, albeit not all white cats or white cats with blue eyes are deaf. The interaction of additional genes and/or environmental variables may contribute to the varied penetrance of deafness and eye color.
Blindness affects white dogs?
Two coat patterns, each of which results in restricted color swatches on a dog’s coat and skin, are produced by limited coloration in non-albino dogs. In breed standards and kennel associations, these patterns are referred to as “merle” and “piebald.” Piebald dogs have coats that are primarily white with noticeable dark spots or patches. Merle-coated dogs have spots or patches of color on their skin in addition to their coats.
Additionally, dogs with merle coats are more likely to have heterochromatic, or various-colored, eyes. White and albino dogs are not inherently more likely to be born blind or deaf because, like in white cats, the genes responsible for coat color, eye, and ear health are not causally connected. A unusual genetic combination called “double merle” does, however, come with some built-in health hazards. It’s possible to mistake Keller, a double merle dog, for an albino dog. Contrary to double-merle-coated dogs, which are more susceptible to both hearing and blindness, true albino canines are normally healthy, with the exception of light sensitivity.
