A quick and non-invasive diagnosis of deafness in dogs is achieved through Brainstem Auditory Evoked Response (BAER); a test where the electrical activity of the brain in response to an auditory (click) stimulus is recorded and displayed on a computer screen.
BAER testing is a technique that can be used to assess the hearing status of adult animals where there is a concern about deafness, or prior to breeding and puppies before they go to their new homes.At present, approximately 13.6% of Dalmatians tested at the Animal Health Trust are unilaterally deaf (deaf in one ear), while 4.9% are bilaterally deaf (deaf in both ears). The lower prevalence of deafness in Dalmatians we test (18.5% affected), where blue eyed dogs are not bred from, when compared with the US population (29.7% affected), where blue eyed dogs are used as breeding stock, seems to imply that removing blue eyed individuals from the breeding population could reduce the prevalence of affected offspring. This is supported by recent information from the US, which shows a statistically significant relationship between deafness and blue eyes.The anatomical changes that take place in the inner ear due to this disorder have been extensively studied. Microscopic examination has shown that the deafness that affects Dalmatians is caused by degeneration of the blood supply to the cochlea (a spiral-shaped structure in the inner ear). in the first few weeks of life. This is followed by destruction of the hair cells and ultimately further deterioration of components of the inner ear and nerve degeneration. The loss of the hair cells is permanent and irreversible. The passage of sound to the auditory nerve is interrupted, i.e. sound cannot “get in” to the auditory pathway, resulting in the dog becoming deaf.
BAER testing is a technique that can be used to assess the hearing status of adult animals where there is a concern about deafness, or prior to breeding and puppies before they go to their new homes.At present, approximately 13.6% of Dalmatians tested at the Animal Health Trust are unilaterally deaf (deaf in one ear), while 4.9% are bilaterally deaf (deaf in both ears). The lower prevalence of deafness in Dalmatians we test (18.5% affected), where blue eyed dogs are not bred from, when compared with the US population (29.7% affected), where blue eyed dogs are used as breeding stock, seems to imply that removing blue eyed individuals from the breeding population could reduce the prevalence of affected offspring. This is supported by recent information from the US, which shows a statistically significant relationship between deafness and blue eyes.The anatomical changes that take place in the inner ear due to this disorder have been extensively studied. Microscopic examination has shown that the deafness that affects Dalmatians is caused by degeneration of the blood supply to the cochlea (a spiral-shaped structure in the inner ear). in the first few weeks of life. This is followed by destruction of the hair cells and ultimately further deterioration of components of the inner ear and nerve degeneration. The loss of the hair cells is permanent and irreversible. The passage of sound to the auditory nerve is interrupted, i.e. sound cannot “get in” to the auditory pathway, resulting in the dog becoming deaf.
We use EBV's (Estimated Breeding Values) for good hearing results in all LUA litters. To date out of 100 puppies born all but one have been bilateral hearing... just one uni and no deaf.. Again proving if you really want to breed for the dogs ... you can!
EBVs use information about the phenotypes of a dog and its relatives to predict genotype of a dog, its "breeding value" for a particular trait.
So with this in mind if you go to the puppy page, you will see the hearing record of ALL planned litters.
To quote Dr George Strain, an authority on the genetics in Dalmatian deafness...
EBVs use information about the phenotypes of a dog and its relatives to predict genotype of a dog, its "breeding value" for a particular trait.
So with this in mind if you go to the puppy page, you will see the hearing record of ALL planned litters.
To quote Dr George Strain, an authority on the genetics in Dalmatian deafness...
. "extreme caution must be used when line breeding of dogs related to deaf dogs, whether the deafness is unilateral or bilateral. To make these decisions in an informed manner for breeds with known deafness, it is important that advantage be taken of hearing testing facilities. Unilaterally deaf dogs cannot be detected by other means, and these dogs WILL pass on their deafness genes"
