Primary Lens Luxation
Eye Panel Examiners
Hearing Test Centres in the UK
Defects Advice - Deafness
in dogs should be easily detected if it is
bilateral - in other words, it occurs in both ears.
bilaterally deaf puppy is unresponsive to
loud noises, and will use mainly visual cues to interact with its
are only deaf in one ear, and can often compensate for this so well
that they can
react in exactly the same way as puppies with normal hearing. The
only way to reliably identify a
unilaterally deaf puppy is to carry out a Brainstem Auditory Evoked
on the whole, can lead normal lives, however studies have shown that if
are bred from, the incidence of unilateral and bilateral deafness in
progeny is greatly increased.
Collies have also been noted as being
particularly prone to middle aged onset deafness – initially
are known to
have normal hearing, however sometimes as early as 4 years of age, they
is currently underway in the United States for a possible genetic basis
testing can be carried out on adult dogs
before they are used for breeding, or on puppies before they leave the
It gives a
clear result, and is
not reliant on any conscious response from the dog.
dogs and puppies may find the procedure
slightly stressful, and require a light sedative, however many remain
relaxed throughout the procedure. During
the test, a headphone is placed over one ear, which sends a series of
into the ear.
hearing in that ear
is normal, sensors placed around the head pick up signals which then
waveform on the screen of the equipment that should show characteristic
procedure is then
repeated for the other ear.
Animal Health Trust (AHT) has been reviewing
results for Border Collie BAER tests, and has found an incidence of
bilateral or unilateral deafness in the breed. This
is significantly higher than the
incidence of deafness in the
canine population as a whole, which is estimated at 0.025%. At
the AHT, analysis of the pedigrees and
certain physical characteristics - such as the extent of white
merle gene and the presence of blue eyes - are being correlated with
results and DNA sampling, in order to find the cause of deafness in the
data that is obtained,
the quicker the answer will come. All
results are kept in the strictest confidence, and no individual persons
will be identified in the findings.
testing centres are relatively few and far
between in the UK.
A list of
carrying out the testing can be found at the end of this health section. Costs
can vary, but may be around £25 -
depending on whether sedation is required.