Congenital, sensorineural, hereditary deafness is seen in about 60 breeds of dogs as well as several breeds of white-coated cats. The most commonly affected breeds of dogs are Dalmatians, Bull Terriers, Border Collies, Australian Cattle Dogs, English Setters, and Bull Dogs. These animals can be either completely deaf or suffer hearing loss in just one ear. As a result, simple methods such as rattling keys or clapping will not identify all affected animals. As a unilaterally deaf animal has a much greater chance of throwing progeny with hearing deficits, early identification of these animals will help prevent spreading of the problem to future generations.
The most reliable way to assess hearing is to use electrophyiologic tests such as the Brainstem Auditory Evoked Response (BAER) test. This test is objective and non-invasive and can be performed on conscious animals. However, reliable results are also obtained on sedated or anaesthetised patients.
At ChesterGates the BAER test is offered to breeders and can be performed on puppies and kittens which are at least 6 weeks of age. Adult dogs and cats can be tested on an individual basis as well.
The owners are given a record of the results for each animal tested.
Chiari Malformation Screening Scheme
This scheme is open breeders of Cavalier King Charles Spaniels, Griffons and other breeds which are affected by Chiari Malformation or Arnold Chiari Syndrome as it is sometimes referred to in human medicine. The scheme offers a quick, reduced rate, MRI scan to look for the presence or absence of cerebellar herniation, ventricular dilation, syringomyelia and/or middle ear exudates.
This scheme is not intended for dogs who are already showing obvious clinical signs of Chiari Malformation. Clearly affected dogs need to be referred to the neurology team at ChesterGates in the usual way. Dogs being presented for this scheme need to be microchipped (this can be done on the day) and have a 'clean bill of health' from their usual veterinary surgery. Dogs on this scheme often have a BAER hearing test at the same time.
Owners are given a record of the results for each animal tested and they need to present the Kennel Club registration forms for all dogs being tested under the scheme.