Health and Genetic Testing

You will see a lot of information on my site about health testing.  I feel like I should add information about the tests and links to the sources so people can learn more:

  • Any test listed in BOLD - A test that is mandatory for the Canine Health Information Center.
  • Any tested listed with an * - A test that is recomended by the Australian Shepherd parent club.
  • All test listed by name only - An optional test.

OFA Hips - Excellent, Good or Fair are passing scores.  Screening for a condition of the hip joint in which the bones are not properly formed. It results in a loose hip socket to thighbone connection causing hip pain and lameness ranging from mild to crippling.

OFA Elbows - Normal is the only passing score.  Screening for a condition of the elbow joint in which the bones are not properly formed. It results in a loose elbow connection causing pain and lameness ranging from mild to crippling.

OFA Dentition - the purpose of the database is to certify that all adult teeth are fully erupted and present. It is not intended to certify compliance with any specific breed standard.

OFA Eyes - Yearly screening Clear equals Pass.  Aussies can inherit a number of eye defects which impair vision in varying degrees or cause complete blindness. They include ocular coloboma, iris coloboma, juvenile and senior cataracts, detached retina, persistent pupillary membrane, progressive retinal atrophy and distichiasis.

Hereditary Cataracts* - Hereditary Cataracts (HC) are a clouding of the lens of the eye caused by a breakdown of tissue in the eye. This condition generally results in an inability to see clearly and can cause total blindness. In canines, cataracts are often familial; this type is known as Hereditary Cataracts.  In this case, the dog is typically affected bilaterally, in that both eyes are affected by the cataracts. The cataracts associated with HSF4 also occur in the posterior region of the lens. They usually start by being small and grow progressively, though the speed of growth is highly variable. Some cataracts will grow so slowly that the dog's vision remains relatively clear, while others will grow such a way that the dog will quickly go blind. Corrective surgery is possible, though it is costly and is not always effective.

Multi Drug Resistance* - Some dog breeds are more sensitive to certain drugs than other breeds. Aussies can have adverse reactions to drugs such as ivermectin and loperamide (Imodium). Drug sensitivities result from a mutation in the multi-drug resistance gene (MDR1). Dogs with the mutant gene cannot pump some drugs out of the brain as a normal dog would. The result may be an illness requiring an extended hospital stay - or even death.

Cone Degeneration (CD) -  Cone Degeneration disease causes day-blindness caused by a lack of cone function in the retina of the eye.  CD disease causes degeneration of the retinal "cones" that respond primarily to bright daylight, resulting in what is referred to as "day blindness." Cone-degenerate pups develop day-blindness and photophobia between 8 and 12 weeks of age, the age when retinal development is normally completed in dogs. Symptoms of CD are present only in bright light and the dog's vision is not affected in dim light.

Canine Multifocal Retinopathy (CMR) - The mutation causes raised lesions to form on the retina which alters the appearance of the eye but usually does not affect sight. The lesions may disappear, or may result in minor retinal folding. Symptoms of the mutation usually appear when a puppy is only a few months old, and generally do not worsen over time.

Degenerative Myelopathy (DM) is a progressive neurological disorder that affects the spinal cord of dogs. Dogs that have inherited two defective copies will experience a breakdown of the cells responsible for sending and receiving signals from the brain, resulting in neurological symptoms.  The disease often begins with an unsteady gait, and the dog may wobble when they attempt to walk. As the disease progresses, the dog's hind legs will weaken and eventually the dog will be unable to walk at all. Degenerative Myelopathy moves up the body, so if the disease is allowed to progress, the dog will eventually be unable to hold his bladder and will lose normal function in its front legs. Fortunately, there is no direct pain associated with Degenerative Myelopathy.

For genetic tests you will see the following results:

  • N/N - Not afected
  • N/M - Carrier
  • M/M - Affected

These are just tools, while every breeder wants N/N many carriers of these genetic disorders have absolutely no symptoms (they just carry one copy of the marker) in most cases that means breeding an N/M to an N/N will help irradicate the diesease in generations to come.

What else does all this testing mean?  It means the breeder is serious about testing and wants to know the most information they can on their dogs.  Some of the tests are very new and to me I want to know as much as I can and this is why you will see many tests on my dogs.