Faithwalk Aussies and Miniature American Shepherds

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I am updating this page on my site to include the newest DNA tests available for Aussies and Mini American Shepherds. I get my panels done with Animal Genetics, a lab I trust. Here is the page for the canine diseases.

https://www.animalgenetics.us/Canine/Genetic_Disease/Disease_Index.asp

The disease traits we need to do include HSF4 hereditary cataracts, which account for about 70% of cataract cases. There are quite a few other forms of cataracts these breeds can develop, which is why an annual eye exam with a canine opthalmologist is important. We can test for a few other eye diseases too, but not all.

The next test I do is MDR1. Multi-Drug Resistance Gene (MDR) codes for a protein that is responsible for protecting the brain by transporting potentially harmful chemicals away. In certain breeds, a mutation occurs in the MDR1 gene that causes sensitivity to Ivermectin, Loperamide, and a number of other common drugs. Dogs with this mutation have a defect in the P-glycoprotein that is normally responsible for transporting certain drugs out of the brain. The defective protein inhibits the dog's ability to remove certain drugs from the brain, leading to a buildup of these toxins. As a result of the accumulation of toxins, the dog can show neurological symptoms, such as seizures, ataxia, or even death.

Both HSF4 and MDR1 are dominant incomplete penetrance genes, meaning it only takes one copy to be affected. I will not breed a dog with HSF4, but will MDR1 because it’s too common to remove all one or two copy dogs from the gene pool. Knowing the dog’s MDR1 status allows us to choose safe drugs and medications.

I also test for CEA, prcd-PRA, CMR1 and CD. All are eye diseases, Collie Eye Anomaly, Progressive Retinal Atrophy (the form these breeds can have), Canine Multifocal Retinopathy, and Cone Degeneration. These are all simple recessive traits so a dog with one copy is a carrier, not affected, and may be safely bred to a mate that is clear.

The last tests I do include HUU which is Hyperuricosuria. Dogs with this genetic mutation metabolize waste products as uric acid in their urine. The uric acid forms into hard stones in the bladder, causing pain and inflammation as the stone moves through the urinary tract.

The other test is Degenerative Myelopathy (DM). This is a progressive neurological disorder that affects the spinal cord of dogs. Dogs that have inherited two defective copies can experience a breakdown of the cells responsible for sending and receiving signals from the brain, resulting in neurological symptoms.

Some breeders only want “clear panel” dogs but that’s throwing the baby out with the bathwater. You further restrict or even choke the gene pool by doing that. These tests should be used as tools to plan breedings in such a way to avoid affected dogs. And DNA tests are just a part of the puzzle, we still have to consider the other health aspects for which there is no DNA test, such as hip and elbow dysplasia (which we can at least look at via x-rays and submit those to OFA for evaluation), and things like epilepsy, auto immune disorders and such.

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For other health tests, let’s start with eye exams.  It used to be called CERF but that organization closed, so now  it’s CAER and submitted through OFA.   Since various eye problems are common in all breeds and mixes of breeds of dogs, including Aussies and MAS, each year we get all our dogs' eyes examined by a board certified canine opthamologist.   Most of the time we are able to get our pups' eyes checked before they leave for new homes, which is ideal.   The puppy exams can depend on weather and timing, since our eye doctor only holds clinics once, and sometimes twice a month, 100 miles from here.  It isn't the most convenient thing to load up all the dogs for a long trip, but I feel it is part of what we need to do. Experts feel very strongly all breeding dogs should have the annual CAER exam.  If possible Aussie and MAS pups should have their first one before 8 weeks of age.  The opthamologist can sometimes see things in puppies at 7 to 8 weeks of age that they will not see again for a few years. However, with the advent of CEA testing, the early exams are not quite as critical.  The reason the test is done annually is that like in people, eyes can change over time.   It's not a guarantee a dog will never pass on inherited eye problems, but will lower the chance since the dog itself is not affected.  At the time of the exam a form will be provided and signed by the doctor, showing the dogs have normal eyes or if there is a problem, what it is and where it is located in the eye.  Copies can be provided to puppy buyers or a breeder can send that into CAER for an official certificate.