Genetic Diseases of the Corgi
Corgis have genetic diseases that they could inherit, that is why here at AW Corgis we genetically test all of our corgis through Embark. From this we are able to obtain information on genetic diseases, traits, coat and body characteristics.
We know that DM, EIC, vWD1, X-SCID and PRA-rcd3 are inherited diseases in Corgis. All of our breeding corgis are free of the these diseases.
Research has shown that hip dysplasia and IVDD, both found in Corgis, are more complex and is not only a genetic but an environmental component.
Genetic Diseases
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What is PRA-rcd3?
This genetic disease causes blindness.
What are the symptoms?
Puppies are normally diagnosed by the time they are 8 weeks old. They develop night blindness first then total blindness by 1 to 4 years of age.
Is there a treatment?
There is no treatment.
Genetic testing & our breeding program
We test al of our breeding dogs for PRA -rcd3.
We have no dogs who carry genes for this disease.
What genetics are involved?
The gene involved is PDE6A on chromosome 4.
This disease is a recessive autosomal genetic disease, meaning that for a dog tobe affected it must inherit 2 copies of the mutation (one from each parent).
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What is vWD1?
Von Willebrands disease is a blood clotting disorder. There are 3 forms of this disease and Pembrokes may inherit type 1.
What are the symptoms?
Some dogs with Von Willebrands disease may not show any symptoms while others bruise easily or severely bleed from wounds or during surgery. Your vet may perform a clotting time test prior to spaying or neutering to make sure that a problem does not exist.
Is there treatment?
vWD cannot be treated, only managed. Preventing injuries is goal number one. If your dog requires surgery, your veterinarian should be warned that excessive bleeding may occur and blood products need to be on hand in case a transfusion is required.
Genetic testing and our breeding program
We test ALL of our breeding dogs for vWD1 and use these results to plan matings to ensure that no “affected” puppies are produced.
We do not have any vWD1 affected dogs in our breeding program.
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What is X-SCID?
X-SCID is a rare immune disorder characterized by the puppy’s inability to fight recurrent systemic or localized infections of the eye, ear or respiratory system, as well as conditions such as distemper. When symptoms of the disorder arise in puppies under six months of age, X-SCID is attributable to inherited chromosomal mutation. These affected puppies will die anytime within six months of birth. Cause of death is ascribed to a failure to thrive or fallen puppy syndrome.
What are the symptoms?
Puppies with this genetic disease are normally identified by the time they are 6-8 weeks of age. They do not grow properly, lose weight, are lethargic, and may have diarrhea and vomiting.
Is there a treatment?
Most affected puppies will die between birth and six months of age due to their immune system not being able to fight off infections.
Genetic testing & our breeding program
We test ALL of our breeding dogs for X-SCID.
We have no breeding dogs who carry genes for this disease.
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What is EIC?
Exercise Induced Collapse is a neuromuscular disorder that causes muscle weakness after strenuous exercise.
What are the symptoms?
Most dogs develop signs typically before 3 years of age. Most dogs with EIC will appears normal during low to moderate exercise but will become wobbly and may collapse after 15-20 minutes of strenuous exercise. Dogs normally remain alert during an episode howeve confusion, loss of consciousness, seizures and in rare cases death can occur.
Is there a treatment?
A dog that has been diagnosed with EIC should make sure that they do not participate in activities that require intense exercise. High environmental temperatures have been known to aggravate symptoms of this disease.
Genetic testing & our Breeding Program
We test ALL of our breeding dogs for EIC and use the results to plan matings to ensure that no “at risk” puppies.
We do not have any EIC at risk or affected dogs in our breeding program.
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What is DM?
DM is a neurological disorder that affects the spinal cord. Specifically, myelin, the covering around the nerve fibers that helps nerves conduct electrical impulses breaks down.
What are the symptoms?
Affected dogs do not usually show signs of DM until they are at least 8 years old. The first nerves affected are those that control the hind legs. Weak rear leg muscles and an abnormal gait are normally the first signs observed. The condition progressively gets worse until the dog is paralyzed. If you have ever seen a dog using a cart for a paralyzed backend they most likely had DM.
Is there a treatment?
Unfortunately, there is no treatment for DM. The only way to diagnose DM requires microscopic analysis of the spinal cord after death. However, veterinarians use clues such as genetic testing, breed, age, and other diagnostics to determine if DM is the most likely cause of your dog’s clinical signs.
Genetic testing and our breeding program
We test ALL of our breeding dogs and then use this information to plan matings to ensure that no “at risk” puppies are produced.
We do not have any DM affected dogs in our breeding program.
Genetic Diseases
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A little background info...
Corgis are a dwarf or chondrodysplasia breed. Their shortened leg bones is due to mutations in two chromosomes - 12 and 18.
Dogs that have the mutation on chromosome 18 will have shorter legs than normal. Dogs that have mutations on both chromosomes will have even shorter legs.
Here is where the problem comes in, the mutation on chromosome 12 (FGF4) is linked to IVDD therefore if a dog has this mutation on chromosome 12 they have shorter legs.
As long as a dog has at least one copy of this mutation they are at risk for IVDD. Having 2 copies does not increase the risk however it does result in shorter legs.
What is IVDD?
IVDD is a back or spine issue where discs in the back rupture or bulges and applies pressure on the spinal cord.
What are the symptoms?
Dogs with IVDD experience pain in their back and neck, may have an abnormal gait, loss of balance and may experience weakness in their rear legs.
Is there a treatment?
IVDD is treated based upon severity. Treatment might include rest, pain management or it may require surgery in extreme cases.
Genetic testing & our breeding program
Since breed standards stat that the Pembroke Welsh Corgi must have short legs, all modern Corgis should have at least one copy of the FGF4 mutation on chromosome 12.
Our Corgis are no exception, all have at least one copy of this mutation on chromosome 12.
How does the environment play a role?
Dogs with at least one copy of the FGF4 mutation have a increase risk of developing IVDD but most Corgis neve develop this disease.
Environmental factors play a HUGE role in determining if a dog who is at risk will actually develop IVDD. By taking a few precautions you can reduce the risk of your dog developing IVDD.
These environmental factors include:
Diet
Feeding a high quality dog food has been shown to reduce IVDD and hip dysplasia. We feed all of our dogs a raw balanced diet.
Weight Management
Weight should be kept in check to prevent extra stress on the spine.
Exercise
Exercise hels build strong muscles, tendons and ligaments however, taking care o not over exercise is critical. A well planned exercise program should sta t inpuppyhood. We always send home a booklet that outlines age appropriate exercises that you can do with your puppy.
Also taking care to make sure that puppies do not play too hard with other puppies or dogs is advised.
Minimize jumping off furniture
Jumping off furniture or other objects higher htan the dog’s shoulder applies extra stress to the ack and skeleton and may herniate discs. Training your dog to use a ramp to get onto and off of furniture is much safer and does not apply stress to the skeleton.
Walk with a haness rather than a leash
Walking your dog with a harness reduces stress on the vertebra of the neck.
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What is hip dysplasia?
Hip dysplasia is a condition where the joints are loose. The laxity allows the head of the femur bone to not align properly in the hip socket. Over time this misalignment leads to abnormal wear on the cartilage surfaces resulting in inflammation, pain and osteoarthritis.
Current testing and test problems
There is not a genetic test available.
There are 2 organizations that will rate hips on dogs, OA and Pennhip. Dogs are sedated and x-rays are taken. This needs to be performed by veterinarians who have undergone training on how to properly align hips during the procedure. These x-rays are then sent off to OFA or Pennhip where they are graded by radiologists.
There are several problems with this method. One is that if the dogs legs are not aligned properly during h x-ray, the x-ray will not be accurate. The other is that there may be human error in actually scoring the x-rays.
The OFA classifies hips into 7 categories:
Excellent, Good, and Fair - these are all within normal limit
Borderline - results are not clear
Mild, Moderate and Severe - these all indicate some form of dysplasia
We still perform OFA or Pennhip test on our breeding dogs.
How dos the environment play a role?
Environmental factors play a HUGE role in determining if a dog will develop hip dysplasia. Research shows that all puppies are born with normal hips therefore hip dysplasia is not a congenital defect but environmental factors starting in puppyhood.
What we do to prevent hip dysplasia
Providing excellent footing in the whelping crate
Controlling weight in pregnant females
Monitoring weight in dogs
Scheduled feedings for our puppies - No free feedings
Feeding a high quality food
Age appropriate exercise
What you can do as dog owners
Provide excellent footing
Monitor your dogs weight
No stairs for the first 3 months
Feed a high quality food
Age appropriate exercises