What Is Degenerative Myelopathy (DM) in Corgis?

Degenerative myelopathy, or DM, is one of the first things I test for before any breeding. It is also one of the most misunderstood. Here is what it is, what it is not, and how a responsible breeder keeps it out of your puppy's future.

What is degenerative myelopathy?

DM is an inherited disease of the spinal cord. In affected dogs, the nerves that carry signals to the hind legs slowly break down, usually later in life. The first signs are often a wobbly back end or scuffing of the back paws. Because it appears in older dogs, a puppy can look perfectly healthy and still carry the genes.

That is the reason testing the parents matters so much. It is far easier to prevent DM in a pairing than to deal with it years later.

How does the DNA test work?

A simple cheek swab or blood sample shows which version of the gene a dog has. A dog that is clear has two normal copies and cannot pass DM on. A carrier has one copy of the changed gene and is not expected to develop the disease. A dog that is at risk has two copies of the changed gene.

The test is done once, and the result is permanent.

Can carriers be bred responsibly?

Yes, with planning. If a carrier is bred to a clear dog, no puppy will be at risk, though some may be carriers. Our rule is simple: an at-risk dog is only bred to DM-clear mates. That is exactly the plan for our Muffin, who is DM at risk.

Each puppy listing on our Puppies page notes the parents' status, such as DM carrier or clear.

What should buyers ask?

Ask the breeder for the DM result for both parents, not just a statement that the dogs are health tested. A good answer names the dam and sire and gives the result. You should also ask about vWD1 and EIC testing and OFA exams on hips, elbows and eyes.

Our guide to corgi health tests lists what each of those means.

Does a clear result mean a dog is guaranteed healthy?

No test covers everything. DM clear means a dog will not develop that specific disease. Overall health still depends on good nutrition, a healthy weight, exercise and regular vet care. Keeping a corgi lean is one of the best things you can do for its back and joints.

Our two-year health guarantee covers genetic issues and conditions, excluding hip dysplasia and IVDD.

What are the signs to watch for?

Early signs typically appear in older dogs and include a wobbly or swaying back end, dragging or scuffing of the hind paws, and difficulty rising. These signs can also come from other conditions, such as arthritis or a disc problem, so please see your vet for a proper exam rather than assuming.

Because DM is genetic, clear parents are the best protection against it.

What does this mean for a puppy buyer?

A puppy from DM-clear parents cannot develop DM. A puppy with one carrier parent will be clear or a carrier, and will not be at risk. Knowing the status of both parents lets you understand your puppy's genetic picture before you ever bring it home.

Each of our puppy listings notes DM carrier or clear, so there is no guessing.

How do you keep your corgi healthy for life?

Keep your corgi at a lean weight, give regular moderate exercise, use ramps for furniture and cars when possible and schedule routine vet checks. These habits help a long-backed breed stay comfortable well into old age.

If you would like to talk through health testing before you apply, call or text me at (660) 234-5656.

Is there a treatment?

There is currently no cure for DM, and your vet can talk about supportive care, rehabilitation and comfort measures if a dog is affected. Because the condition is inherited, prevention through testing and careful pairing is by far the best approach.

If you are worried about a dog's mobility, schedule a vet exam, since other conditions can look similar and some are treatable.

Where can you learn more?

Your veterinarian is the best source for questions about a specific dog. Breed clubs and the OFA also publish information about inherited conditions in Pembroke Welsh Corgis.

If you are comparing breeders, ask each one how they use DM results when planning litters. A clear, simple answer is a great sign.

What can you do if you have questions about a specific litter?

Call or text me at (660) 234-5656 and I will walk you through the pedigree and results. You can also read about each of our dams and sires on the Our dogs page, then request the Puppy Questionnaire when you are ready.