Degenerative Myelopathy in Dogs

Category: Nervous System & Behavioral
Inheritance: Autosomal recessive
Breeds documented: 49
Published sources: 12

Overview

Damage to the spinal cord gradually weakens the back legs and makes movement less coordinated. Degenerative myelopathy usually develops in older dogs and may eventually prevent walking. Later, the front legs can also become affected. Known gene variants increase risk, but carrying a risk variant does not mean a dog will develop the disease.

Signs to watch for

Struggling to get up
Weakness in the back legs
An unsteady, poorly coordinated walk
Back toenails becoming scraped down
Gradual loss of muscle in the back legs

Signs usually begin around eight years of age or later.

When to get help Book a vet visit when you notice back-leg weakness or an unsteady walk.

Diagnosis and tests

A vet assesses nerve function and rules out other spinal cord diseases using blood tests and imaging. Testing fluid around the brain and spinal cord may also help. There is no single definitive test during life. DNA testing identifies known risk variants but does not confirm that symptoms are caused by this disease.

Breeds with documented risk

49 breeds

By breed size

11 Small
17 Medium
12 Large
9 Giant

All 49 breeds, A to Z

Airedale Terrier Source pubmed.ncbi.nlm.nih.gov
American Eskimo Source pubmed.ncbi.nlm.nih.gov
American Water Spaniel
Australian Shepherd Source pubmed.ncbi.nlm.nih.gov

Bernese Mountain Dog Source pubmed.ncbi.nlm.nih.gov
Bloodhound Source pubmed.ncbi.nlm.nih.gov
Bohemian Shepherd Source old.kpchp.org
Borzoi Source pubmed.ncbi.nlm.nih.gov
Boxer Source pubmed.ncbi.nlm.nih.gov
Boykin Spaniel
Brazilian Terrier Source journals.plos.org
Broholmer Source journals.plos.org

Dorgi Source petmd.com
Dutch Shepherd

English Springer Spaniel Source pubmed.ncbi.nlm.nih.gov

Finnish Hound Source journals.plos.org

Hovawart Source pubmed.ncbi.nlm.nih.gov

Kerry Blue Terrier Source pubmed.ncbi.nlm.nih.gov
Komondor Source pubmed.ncbi.nlm.nih.gov

Labrador Retriever Source pubmed.ncbi.nlm.nih.gov

Mastiff

Nova Scotia Duck Tolling Retriever

Rhodesian Ridgeback Source pubmed.ncbi.nlm.nih.gov
Romanian Mioritic Shepherd Source pmc.ncbi.nlm.nih.gov

Shepadoodle Source petmd.com
Sheprador Source petmd.com
Shetland Sheepdog Source pubmed.ncbi.nlm.nih.gov
Siberian Husky Source pubmed.ncbi.nlm.nih.gov
Soft Coated Wheaten Terrier Source pubmed.ncbi.nlm.nih.gov
Spanish Mastiff
Stabyhoun Source journals.plos.org
Staffordshire Bull Terrier

Wire Fox Terrier Source pubmed.ncbi.nlm.nih.gov

Inheritance

This condition has more than one known form, and different breeds inherit it in different ways. The sources list the form found in each breed.

Autosomal recessive
A dog is affected only if it inherits two copies of the gene variant, one from each parent. A dog with one copy is a carrier: usually healthy, but able to pass the variant on. When two carriers are bred, on average one puppy in four is affected. A DNA test can tell clear, carrier and at-risk dogs apart.
As stated by OMIA
Autosomal recessive, incomplete penetrance
This is inherited like a recessive trait, so two copies are needed. But not every dog with two copies develops the condition. Age, other genes and environment also play a part. A DNA result shows risk, not certainty.
As stated by UC Davis VGL

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.