Determining whether or not a dog is deaf can change the life of both the dog and the family. When the diagnosis of deafness is determined, the family is better able to understand the behavior, needs, and communication methods necessary in establishing a wonderful, loving bond. All too often dogs who are deaf are thought to be stubborn, refusing to listen, or uncooperative. In fact, deaf dogs who are not diagnosed are simply trying to live in a world that does not accommodate their uniqueness.
The following article offers some information on how a deaf dog is diagnosed through the Brainstem Auditory Evoked Response (BAER) test. The earlier that this determination can be made in a deaf dog’s life, the better. The misunderstandings involved when a deaf dog is not known to be deaf are eliminated thus creating a higher quality of life for the deaf dog.
Hogan is on the left and Georgia is on the right. (1996)
Our Hogan and Georgia were diagnosed at Tufts Univerity’s Foster Small Animal Hospital in Massachusetts. A local Dalmatian Dog Club challenged us by stating that our deaf dogs were not deaf at all but stubborn and refusing to listen. “Selective hearing,” stated one member. My husband, Jim, and I decided to make absolutely certain that Hogan and his little sister, Georgia, were indeed deaf. At the very least, we could also find out whether they could hear on some pitch frequencies. The result - total deafness. Hogan’s test revealed a completely flat line and had absolutely no hearing. Georgia had a small hearing range of extremely high pitch sounds. In all intents and purposes, she was deaf.
Deaf dogs are capable of learning, playing, living in a hearing world, and loving - the sky is the limit.
Great appreciation is given to UP’s Onderstepoort Veterinary Hospital for this valuable information.
UP's Onderstepoort Veterinary Hospital invests in a new device to test dog deafness
The University of Pretoria’s (UP's) Onderstepoort Veterinary Academic Hospital (OVAH), in the Faculty of Veterinary Science, has invested in a Brainstem Auditory Evoked Response (BAER) device to test deafness in dogs.
The veterinary hospital is currently testing 20 to 30 dogs a month, most of which are puppies. The new device being used at OVAH to do this test is the American-manufactured UFI BAERCOM, which quickly and painlessly assesses the dog’s level of hearing or deafness.
“We had an older, larger, clumsy device prior to this one, as we have been doing deafness testing for some time, but it had become unreliable to the point that we could not do any BAER tests for about two years,” says OVAH Small Animal Medicine section head and senior lecturer Dr. Paolo Pazzi.
The BAER test detects electrical activity in the cochlea and auditory pathways in the brain in much the same way that an antenna detects television signals. The test is painless, and the puppy or dog is usually lightly sedated as movement interferes with the results.
Sedated pup undergoing BAER test. Hogan and Georgia were not sedated and responded to all my words in American Sign Language. (While hand gestures were used with dogs, Hogan was among the very first deaf dogs to understand ASL. Tufts University staff was enthralled at their performance and became quite involved with Hogan over the years.)
Small electrodes are positioned on the animal’s head and connected to the device, which reads and interprets the brain’s response to a specific clicking noise generated by it.
Each ear is tested individually as the dog may only be deaf in one ear. If they can hear in the ear, the machine’s screen will show a recording of ‘waves’ of varying sizes and depths, but if they are deaf then the screen shows a recording of almost flat lines.
BAER Testing Machine
Once both ears have been tested, the sedation is reversed, and a copy of the results is shared with the owner.
Dogs with congenital deafness can be trained just like a hearing dog (using hand signals instead of speaking) and there are trainers who can assist with this. Many deaf dogs cope very well with hand signals, Pazzi says.
“Deafness in the dog – and cat – the population is low overall, but responsible breeders of predisposed breeds should ensure their puppies can hear and that deafness is not carried in their breeding lines,” he says.
Congenital deafness has been described in more than 80 breeds but is most commonly diagnosed in Dalmatians, Bull Terriers, Australian Cattle Dogs, English Setters, English Cocker Spaniels, and Boston Terriers. There is an association between deafness and pigmentation, with white dogs predisposed and even more so if they are white with blue eyes.
“It is important for dog breeders and people getting a puppy to make sure there is no congenital deafness in the line, particularly in breeds that are more susceptible to it. Other reasons for testing include owners who are concerned that the dog they have adopted is deaf, or if their elderly dog has become deaf.”
EDITED BY: CHANEL DE BRUYN
CREAMER MEDIA SENIOR DEPUTY EDITOR ONLINE
