Why are some Aussies deaf?
The most common cause of deafness in Aussies is a lack of melanocytes (pigment cells) in the inner ear. These cells help translate air vibrations caused by sound into electrical impulses that travel to the brain. If the cells are absent, the dog will be deaf. This form of deafness is present from birth.
Deafness can also be acquired, due to chronic ear infections, old age, trauma, or disease but the most frequent cause of deafness in Aussies is due to pigment deficit in the ear.
Why do some Aussies not have pigment cells in the inner ear?
The lack of melanocytes is related to excessive white markings on the head. Genes which cause white markings can impact not only the skin and hair, but any part of the body that is pigmented. It doesn’t matter whether the white markings are because the dog is a double merle (two copies of the merle gene) or because normal white markings are overextended on the head.
Are all double merles deaf?
Most are because most have a lot of white on the head. Occasionally, if a double merle is from parents that have only a very small amount of white and come from families with little white a double merle may have coloring in the head, in which case it will not be deaf.
Are blue eyes are related to deafness?
Blue eyes may be associated with deafness, but not always. In some breeds, like the Dalmatian, the association is high. In Aussies it does not appear to be a significant factor.
How can I tell if a puppy is deaf?
The most conclusive way is to have a vet do a BAER test. The test is non-invasive and isn’t too expensive. It will tell you if the puppy has total hearing loss in either ear. It can be done in a small animal practice, but not every vet will have one do to the expense of the equipment and isufficient client demand, so you may need to travel to a clinic that offers it.
If BAER testing isn’t readily available, you can do a home test that may tell you if the puppy can hear or not. Put the puppy in a room away from other dogs. The room or space used should offer minimal distractions. Have someone stand on one side of the space to draw the puppy’s attention—not to get it to come, but just to get it to look toward them. A second person should stand on the opposite side of the room. When the puppy is looking at the first person, the second one should make a distinct noise. A wooden spoon hitting the bottom of a pot or squeezing a loud squeaky toy should do it. Don’t do anything really loud or scary; you don’t want to traumatize the puppy. If the pup does not react at all after 2-3 tries, it is likely the puppy is deaf.
What is a BAER test?
BAER stands for Brainstem Audio Evoked Response. This test must be done by a vet who has the proper equipment. It will measure involuntary nerve response to an auditory signal. It can detect whether the dog is deaf in one or both ears. It cannot detect partial hearing loss.
Can an Aussie be deaf in only one ear?
Yes.
How can I tell if my dog is deaf in only one ear?
If a dog is deaf in one ear only, it will have functional hearing but mayl have some difficulty orienting on the direction of a sound. In time most dogs learn to compensate. If you notice that your dog has trouble locating a sound source, or turns toward an echo instead of to you when you call, it may be deaf in one ear. You will need to have the dog BAER tested to confirm that.
If a white spot on the ear in a deaf puppy colors in, will he get his hearing back in that ear?
No. If the puppy is deaf in the ear that has a white spot, that will not change if the ear colors in. Dogs can be deaf in an ear that has pigment on it, though they usually will have a lot of white on the head.
Is it possible to get deafness in a tri to tri cross?
Yes, particularly if a puppy has a lot of white on or close to one or both ears.
If I produce a deaf puppy, can it be placed?
Yes, but it will need someone committed to lifetime care for a special needs dog.
Is deafness hereditary?
In that the underlying cause of almost all deafness in Aussies is a lack of melanocytes in the inner ear and this is a result of too much white on or around the ears, a trait governed by heredity, it is inherited. Not every dog with too much white is deaf, so there are probably additional genetic factors which determine whether the dog is deaf. However, if breeders make efforts not to produce puppies with white on or close around the ears they can significantly reduce the frequency of deafness in the breed. Deaf dogs, including those deaf in only one ear, should not be bred.
How can I avoid producing deaf puppies?
Don’t breed merle to merle. Don’t breed dogs with excessive white markings. If a dog has produced offspring that have excessive white, breed it only to mates that have less white than it does and which come from families where excessive white is uncommon or absent.