Catahoula Issues » Deafness  

Catahoula Issues is a large section of our site.
Please use the links below to navigate the pages within this section.

There has been much debate pertaining to the owning of deaf Catahoulas. Breeders are not readily willing to allow deaf Catahoulas to leave their premises and will generally euthanize the deaf pups. This is to prevent any future breeding of a dog that they know will produce deaf offspring. It is more humane to destroy the pup while it is very young and avoid any future tragedies that could bring pain and hardship to both the dog and the owner.

I have stated that owning a deaf Catahoula could result in a child or person's being bitten by a sleeping dog. I have also been criticized by some that own these dogs and state that the dog is not the keg of dynamite that I claim it to be. These dogs are exceptions, and, as in any other circumstance, there are exceptions to every rule. The majority of those that own this type dog have taken every precaution and have displayed the patience needed to provide a better living environment for the dog, one that would not have been provided had the dog been a hearing one. They take the precautions and time to train the dog, but that does not eliminate any underlying potential to create disaster.

There will be someone to say that I cannot predict the future of any hearing dog, so what authority is given to predict that of a deaf dog. My response is that I cannot predict the future, but I can forewarn those of tragedies that have occurred in the past and could happen to them.

With every care taken to avoid any accidents, I have been informed of deaf dogs that escaped the confines of his home only to be hit by an oncoming car. Yes, hearing dogs have had that happen also, but how many hearing dogs have escaped injury because they could hear the horn blow, or the tires squeal, or the shouting of their owners? No one writes a statement about how their deaf dog escaped their protection through their negligence, and that they lost their beloved animal. It happens, but no one will write about it. They will, however, write about how great their deaf dog is as their family pet.

On the incidence of biting, I have personally dealt with deaf dogs and Catahoulas in general. I can speak very frankly about one in particular that was a family pet that came to me for obedience training. The dog did well during training, and was able to be controlled without any incidents by the young man handling the dog. Three years after that training, when the dog was five (5) years of age, it suddenly and without provocation attacked the 11 year old daughter of the owner while food was being dispensed. The dog had grown accustomed to the young man feeding him, and in his absence the daughter took on the chore. The child experienced great trauma and 64 stitches about her face. The dog was pulled from the child only to bite the owner on his hand. Later, the authorities retrieved the dog from the home and the dog was euthanized. A lot of this could have been avoided.

The thing that needs to be understood is that a Catahoula is a very strong willed dog and likes to be in charge. Training doesn't end. It is ongoing. If you think that you have controlled this breed by training and it's over, you are only fooling yourself. Like children, they will test you to see if you will hold that ALPHA position. This is more true of a Catahoula than any other breed that I've handled. As a Catahoula matures, he will test you. If you do not hold toyour convictions, you will be ruled by him. With this in mind, a hearing dog will respond to those commands that contain Q and K sounds much quicker than any other command. What verbal sound can you make to have a deaf Catahoula stop its actions?

I've attended numerous field trials where a dog is so intent on its job that all the screaming in the world will not stop that dog from what he is doing, and he has to be caught and physically removed from the event. The dog will react when it sees its owner coming after him and will generally respond to the voice command at that time. Not always, but most of the time. What would you do if a deaf Catahoula were to get into that frenzy? What command would you give? How many of those owners that have deaf Catahoulas would rush in and grab a dog that is biting and fighting for what it believes is his job?

Remember, the Catahoula has not been around as long as some other breeds, and they have not had the funding for studies that others have had. In the dog world, this is relatively a new breed. In addition, the Show World has not had as much opportunity to turn these dogs into the shell of a dog that most organizations will do. This dog was bred to work and hunt, and that's what most breeders maintain. This doesn't mean that it can't be a pet, but you have to understand the undertaking and what is required. Just because the dog is deaf doesn't mean that it doesn't need the same exercise, care, maintenance, and training as that of a hearing dog. In fact, it requires more.

The following is an unedited email I received on 11/23/08:
Mr. Abney,
I have thought about you much this week, as it has been the most difficult week of my life. My husband and I contacted you through email about two and half years ago about our deaf Catahoula. You wrote back a very long and heartfelt email saying that we needed to put him down, that he was a ticking timebomb and that, no doubt, it would be worse in the long run.
You were so right. We tried so hard with our Jake, excercising him, taking him to doggie daycare nearly every day, being more forceful at home with discipline. We just couldn't bring ourselves to give up on him when you told us that we should. And it worked, it seemed, for a while. Ultimately, we were unable to help him. His aggression against us was unpredictable and dangerous. He got worse over these two and half years, and bit several people. Luckily, amazingly, no one who sued us or who was horriby hurt. The last time was this week, when he bit me and it felt like he had cracked the bones in my hand. He didn't, but as always, the attack was unprovoked and without warning. He was sick, for he obviously loved me the most, and yet could hurt me in that way.
We had to put him down this weekend. We just couldn't do it anymore. The guilt that we felt was unbelievable, but it was the only option.
Thank you for your honesty those years ago. Your words were, truly, always in the back of my mind. I wanted to make Jake realize that we were helping him, but he was mentally ill, mentally unable to change.
I hope that others never have to go through what we've gone through. Please pass my story along to anyone that you are counseling.
Victoria Scheffler, Fort Worth, TX

I have had an opportunity to provide some puppies to Dr. George Strain in his studies on Deafness in Dogs. I have asked him to write an article for me, and I have reproduced that article here.

Deafness in dogs can result from many causes (aging, drug toxicity, noise, infection, trauma), but the cause of significant concern to owners of Catahoulas and other similarly affected breeds is congenital sensorineural deafness, because it appears to be inherited. Although described as congenital (present at or near birth), the deafness actually is not present until age 3-4 weeks. Cochlear (inner ear) development occurs normally to that point, but the blood supply to the cochlea (the stria vascularis) degenerates, so the hair cells of the cochlea die. This is known as sensorineural deafness because the sensory nerve cells, the hair cells, die. There is no treatment for the hair cell loss, and the deafness is total for each affected ear. Thus, a dog may be unilaterally deaf, bilaterally deaf, or bilaterally hearing. Congenital deafness has been reported in sixty breeds, but it is uncommon in most and usually not proven to be inherited.

The cause of the degeneration of the stria vascularis is not known for certain, but appears to result from the absence of pigment cells (melanocytes) in the stria. The melanocytes are suppressed by the gene (piebald) responsible for white in the hair coat. There is considerable evidence that congenital deafness in many species (including humans) is associated with genes producing white hair.

Dogs that are bilaterally deaf become fairly obvious with time (they don't wake up at meal time or in response to loud noises), but unilaterally deaf dogs usually go undetected because they respond to sounds with their good ear. Their only deficit is difficulty in localizing sound, and they quickly adapt to this. The only way to be certain of a dog's hearing status is to have its hearing tested by the BAER test (see below). Behavioral testing by the owner or a veterinarian will not detect unilaterally deaf animals, and often does not detect bilaterally deaf dogs because they rely heavily on visual and vibratory cues.

Dogs that are bilaterally deaf do not make good pets, and it is strongly recommended that they be put down by the breeder before placement with pet owners who become devastated with the discovery of the deafness, and experience considerable difficulty in raising and caring for these animals. This recommendation is certainly controversial, but there is no shortage of available dogs without obvious genetic defects, and the quality of life for a dog who is constantly being startled is questionable. Because this defect appears to be hereditary, dogs with unilateral deafness should not be bred. I have shown with my research on the Dalmatian breed that deafness incidence nearly doubles in breedings from parents with three good ears between them compared to parents with four good ears. It is very important to know the hearing status of your dog and its potential mate before breeding them.

Based on analysis of the results of hearing tests I have performed on about 50 Catahoulas, the prevalence of deafness is 27% unilateral deafness and 42% bilateral deafness, but these numbers are grossly biased since the testing of most dogs was because owners suspected deafness and insufficient numbers of dogs have been tested to assess true prevalence. Nevertheless, this problem is not trivial in the breed. In the Dalmatian, the most severely affected breed, prevalence is 22% and 8%. There is no difference in prevalence between males and females, no difference between left or right ears, and no apparent difference in prevalence between different color patterns. In other breeds blue-eyed dogs have a greater than normal prevalence of deafness; my experience has been that most of the deaf Catahoulas I have seen have had blue eyes. The likelihood of deafness being present in dogs with at least one unilaterally deaf parent has been shown to be significantly greater in the Dalmatian and English Cocker Spaniel breeds, but insufficient data is available from Catahoulas to confirm a similar effect. Nevertheless, it is extremely likely to hold true.

The mechanism of inheritance of deafness is not known. It does not appear to be sex-linked or simple autosomal recessive or dominant: I have experimentally bred a deaf Dalmatian to another deaf Dalmatian and gotten bilaterally hearing puppies along with deaf puppies. The best guess at this time is that at least two genes are involved. I have been isolating DNA from deaf dogs for several years, and have just gotten a study funded with a colleague to attempt to identify the genetic defect. Much research waits to be performed before we completely understand this problem.

What is the BAER test? The hearing test known as the brainstem auditory evoked response (BAER) or brainstem auditory evoked potential (BAEP) detects electrical activity in the cochlea and auditory pathways in the brain in much the same way that an EKG detects electrical activity of the heart. The response waveform consists of a series of peaks numbered with Roman numerals: peak I is produced by the cochlea and auditory nerve, and later peaks are produced within the brain. The response from an ear that is deaf is an essentially flat line.

Deafness ScanIn the sample recordings shown here, Puppy 1 heard in both ears, Puppy 2 was deaf in the left ear, Puppy 3 was deaf in the right ear, and Puppy 4 was deaf in both ears. Because the response amplitude is so small (fractions of a microvolt) it is necessary to average the responses to multiple stimuli (clicks) to unmask them from the other unrelated electrical activity that is also present on the scalp (EEG, muscle activity, etc).

The response is collected with a special computer through extremely small electrodes placed under the skin of the scalp: one in front of each ear, one at the top of the head, and one between and behind the eyes. It is rare for a dog to show any evidence of pain from the placement of the electrodes - if anything the dog objects to the gentle restraint and the irritation of wires hanging in front of its face. The stimulus click produced by the computer is directed into the ear with a foam insert earphone. Each ear is tested individually, and the test usually is complete in 10-15 minutes. Sedation or anesthesia are not necessary unless the dog becomes extremely agitated, which can usually be avoided with patient and gentle handling. A printout of the test results, showing the actual recorded waveform, is provided at the end of the procedure. Test results are confidential.

George M. Strain, PhD
Associate Vice Chancellor, Office of Research & Graduate Studies, and
Professor of Neuroscience, School of Veterinary Medicine
Louisiana State University
Baton Rouge, Louisiana 70803
Phone: 225-388-5833
Fax: 225-388-5983

For a more in-depth review of deafness please visit:
Deafness in Dogs & Cats Web Page. Strain, G.M. 1999.

References for further reading:
Strain, G. M. 1996. Aetiology, prevalence, and diagnosis of deafness in dogs and cats.
British Veterinary Journal 152:17-36. (Available on web site.)

Strain, G.M. 1999. Congenital deafness and its recognition.
Vet Clinics of North America: Small Animal Practice (in press - July).
(Available on web site.)

Top of Page

Home   |   About Us   |   Catahoula Info   |   Our Catahoulas   |   Site Map


© Abney Catahoulas All Rights Reserved   Terms Of Use