Here is a brief description on some of the health issues that can possibly affect the Miniature American Shepherd. Please follow the links for further information.
We believe information is power. We test our MAS for these genetic health issues and gather as much information on each MAS as we possibly can. This information allows us to make better breeding decisions, so we can produce healthy dogs that will live long and happy lives.
Orthopedic Disorders:
All dog breeds can have orthopedic disease. All Breeders should be testing for dysplasia and luxation before breeding.
Hip Dysplasia
- Canine hip dysplasia is the most common orthopedic disease in dogs.
- CHD is a degenerative, developmental condition, leading to painful hip osteoarthritis, stiffness, and diminished quality of life.
- All dog breeds are affected by CHD
- In some breeds more than 50% of dogs are afflicted.
- The disease is polygenic, multifactorial and is affected by environmental factors such as weight and age.
OFA rated "GOOD" Hips
The inheritance of Hip Dysplasia is not completely understood. Two dogs with no evidence of Hip Dysplasia can still produce affected offspring. Testing for CHD is merely a tool used to better match breeding pairs together in hopes to lower the incidence of Hip Dysplasia from occurring.

Elbow Dysplasia
Elbow Dysplasia is a term used to describe one or more inherited developmental abnormalities in a dog's elbow joint;
- Ununited anconeal process (UAP)
- Fragmented coronoid process (FCP)
- Osteochrondrosis dissecans (OCD)
- Elbow incongruency
OFA "NORMAL" elbows
Patellar Luxation
In Patellar Luxation, the kneecap luxates, or pops out of place, either in a medial or lateral position. Patellar Luxation can lead to degenerative joint disease, lameness and pain.
Examples of OFA / PennHip certificates for
Hip/Elbow Dysplasia and Patellar Luxation
Genetic disorders with DNA tests:
CEA - CH
Collie Eye Anomaly - Choroidal Hypoplasia
The Choroid is a layer of vascular tissue in the eye responsible for supplying blood and nutrients to the retina. Dogs affected with CEA have choroids that did not develop properly with severity varying from dog to dog.
CEA is present at birth and does Not progress.
Mildly affected dogs only have some thinning of the choroid and retain functional vision. Severely affected dogs may have additional eye disorders; iris colobomas, nerve colobomal/stapholma, microphthalmia "small eye", intraocular hemorrhage, retinal detachment, or complete blindness.
CMR1
Canine Multifocal Retinopathy
CD
Cone Degeneration
CD causes the "cone" cells in the retina of the eye to deteriorate, resulting in day- blindness. A puppy will quickly go day-blind and become sensitive to bright light, finding it irritating and even painful.
CD does not affect night-vision.
Affected dogs are able to see at night and in dimly lit areas.
CDDY with IVDD
Chondrodystrophy with
Intervertebral Disc Disease Risk Factor
CDDY with IVDD
Chondrodystrophy with Intervertebral Disc Disease Risk Factor
Dogs affected with Intervertebral disc disease (IVDD) have premature degeneration and calcification of the cartilage discs that connect the vertebrae.
Affected dogs can present with severe back pain, abnormal gait, loss of balance, and limb weakness or paralysis, often requiring surgical intervention.
Affected dogs are at risk of experiencing disc herniations at multiple sites along their spine during their lifetime.
DM
Degenerative Myelopathy
DM is a autoimmune disease that attacks the myelin, the "insulation" of the nerves in the spinal cord, causing progressive paralysis. DM is a late on set disease, appearing around 8 years of age in Miniature American Shepherds.
Symptoms start off with a lack of coordination in the hind limbs; dogs will have an unsteady gait, will wobble and begin to drag their back feet. Within 6-12 months from onset, most dogs are paraplegic and can no longer walk. If allowed to progress, the dog will develop urinary and fecal incontinence and loose respiratory function. DM is not a painful disease. There is no treatment for DM and life ends in euthanasia.
Not every dog with 2 copies of the DM gene will develop symptoms, but those diagnosed with DM will ALL have 2 copies of the gene.
HSF4 - HC
Hereditary Cataracts
Cataracts are a clouding of the lens of the eye caused by a breakdown of tissue. Not all cataracts are hereditary and Not all hereditary cataracts are caused by the HSF4 gene. Not every dog that has the HSF4 mutation will develop cataracts. Instead, having 1 or 2 copies of the HSF4 gene mutation significantly increases the dogs risk of developing bilateral posterior cataracts.
The cataracts caused by the HSF4 gene usually start off small in the back of the lens and progressively develop over time. Some affected dogs will retain functional vision throughout their entire life, while other affected dogs will quickly progress to complete blindness.
MDR1
Multi-Drug Resistance 1
MDR1 is a gene mutation that creates a sensitivity to certain drugs. Dogs affected with MDR1 are defective in their ability to limit drug distribution (particularly in the brain), and also have delayed excretions of drugs that make them susceptible to severe drug toxicity.
The severity of the reaction depends on the dosage given and if the dog is only a carrier of MDR1 or fully affected, seizures and death can occur.
- Dogs that are affected by MDR1 will have a sensitivity to certain drugs.
- Dogs that are carriers of MDR1 may experience some sensitivity to certain drugs.
- Dogs that test clear for MDR1 should not exhibit any drug sensitivities.
Approximately 50% of MAS have at least 1 mutated MDR1 gene.
PRCD - PRA
(Progressive Rod Cone Degeneration - Progressive Retinal Atrophy)
PRCD is a form of PRA, a late onset, inherited eye disease that causes cells in the retina of the eye to degenerate slowly and eventually die. The "rod" cells degenerate first causing night blindness. Then the "cone" cells will slowly degenerate leading to full vision loss.
Dogs need two copies of the PRCD gene to be affected. Affected dogs appear healthy as puppies, but Most will eventually go blind.