© Doris Duewel / Komi, Finland / December 2009
photo by Tuulia Heikkinen / kennel Windwarriors
Why is deafness often a death penalty by humans?
Deafness in the Australian Cattle Dog goes presumably back to the white colour in Dalmatians. Scientifically it is called “Congenital sensorineural deafness”. It is proven by the BAER Test (brain stem auditory evoked response), whereby electrical activities are measured with a special computer as answer caused by the stimulance of needle-electrodes fastened on the skin of the head.
The analysis by an electrical diagnostic test is done by specialized veterinarians. The result is nowadays integrated in many, though not all, breeding regulations of ACD Clubs, and makes the first decision if the puppy will be once a stud dog or stud bitch.
This form of deafness is passed on recessively and is therefore ineradicable.Having that in mind deafness can only be fought by breeding measurements. As there is no genetically test so far for the genes responsible for deafness, the remaining strategy to reduce deafness has been to not breed affected dogs and to breed away from pedigrees with high prevalence rates.
It is clear, the less unilateral hearing dogs are used the smaller the percentage of deafness or half deafmess is in the breed. But for this all breeding ACDs have to be BAER tested.
Unfortunately unilaterally deaf dogs exhibit little if any behavioural evidence of their defect, so affected dogs and bitches that are not BAER tested as puppies or prior to being bred will, when bred, continue to increase the prevalence of the disorder.
But for the sake of the breed, an increasing number of breeders get their puppies tested, even if no breed order is demanding it.
Earlier generations of ACDs were mainly bred and selected for their herding abilities, more than for their hearing abilities. This selection for working quality is still a big profit nowadays. That is the way many uni deaf dogs came to the breed.
Our dogs have an excellent ability to smell, which guarantees their surviving qualities. Compared with this sense hearing was of minor importance. Dogs are flock animals and follow .the other members of the herd and their behaviour.
One might think that a selection for full hearing prevalence is not so important. Unfortunately nevertheless, because if a dog is passing on uni-lateral or bi-lateral deafness cannot be foreseen. Both can happen. It is also not sex-related. Both can be affected.
Uni-lateral hearing dogs can do everything what a full hearing dog can do. He is in no way handicapped by his one-sided hearing ability.
There is no reason to put them down – however they should not be bred and spread the deafness to the gene pool. On the other hand,would all 12.2% uni-lateral and 2.4.% bi-lateral * ACDs be closed out from breeding, the gene pool would lose many other important items at the same time. As consequence the gene pool would be minimized and inbreeding would be increased.
What happens with totally deaf dogs, who failed in the BAER test? For an unfortunate number this is the death penalty by their breeder. The argument is, that they cannot be sold. Do they have to be sold? Can’t they find a caring home, where a sensitive new owner will teach him everything by hand signs?
Deaf puppies are sleeping much deeper and longer than their hearing siblings. Therefore they have a very stable temperament, friendly and outgoing. All these virtues are of great help for a sensitive new owner, when teaching him to obey to hand signs instead of voice.
Whoever got involved with a deaf dog, will not regret that. I once saw in Danmark several dogs of various breeds, hearing or not, I do not know it, who were trained by hand signs, because the training area was surrounded by high apartment houses where earlier was a free field. Dogs aswell as owners were happily and successfully training. Of course, the owner has to stay within the range of sight or smelling. The connection of this team will be especially close. A delighting reward, which we give us and our dog is giving to use. Let a deaf dog have a chance for living!
*2005 296 ACDs were investigated for deafness in Louisiana State University.