Degenerative myelopathy in the French bulldog

Degenerative myelopathy is a degenerative health condition that affects the back legs of affected dogs, and while the condition isn’t painful, it leads to a gradual, slow onset paralysis. Ultimately, the condition is fatal in affected dogs, and cannot be cured or prevented.

Degenerative myelopathy is a hereditary health condition, which means that it is passed on from parent dogs who carry the gene markers for the condition to their young, making it more prevalent in certain dog breeds than others.

The French bulldog is one of the dog breeds that is recognised as having higher risk factors for the condition than most, so much so that a pre-breeding health screening protocol for the condition was added to the breed’s recommended health tests in 2016.

If you own a French bulldog or are considering buying one, it is important to learn about their health and potential health risks, including that of degenerative myelopathy.

In this article we will explain how degenerative myelopathy is passed from dog to dog, how dogs can be tested for the condition, the progression of the condition, and what breeders and puppy buyers need to know to ensure healthy puppies. Read on to learn more.

What is degenerative myelopathy?

Degenerative myelopathy is a progressive condition that causes a type of degenerative disease of the dog’s spinal cord. The condition used to be known by the name of chronic degenerative radiculomyelopathy, and in some clinics these two terms are still used interchangeably.

Degenerative myelopathy doesn’t usually begin to show symptoms until the dog in question is mature – usually over the age of around five but rarely later than eight. This means it is impossible to tell from examining or looking at a younger dog whether or not they will develop the condition as they get older, and of course, the condition’s late onset means that an affected dog may have already been bred from, passing on the gene mutation that causes the condition to their own young.

The first symptoms of degenerative myelopathy in French bulldogs begin with the rear legs, as the muscle tissue weakens. This can lead to instability walking, problems getting up and down, and loss of coordination. However, because of the typical age of onset of degenerative myelopathy, the early symptoms are commonly confused with arthritis.

Degenerative myelopathy worsens over time, and can result in faecal and urinary incontinence, and full paralysis of the dog’s back legs and hindquarters. As the disease reaches its peak, the front limbs and lungs become affected too, so that the dog won’t be able to move around or breathe normally. A decision to put the dog to sleep is usually made at this time, to avoid further suffering.

How long it takes for degenerative myelopathy to reach this stage in the French bulldog can vary a lot from case to case, taking months or even years to reach the point at which the dog’s quality of life is no longer viable.

How is the condition passed on from one dog to another?

Degenerative myelopathy is not contagious, and can only be passed to another dog by inheritance of certain gene faults that are carried by their parent dogs.

Degenerative myelopathy is passed from dog to dog by means of autosomal recessive heredity with incomplete penetrance – although up until a few years ago, the mutation that causes the condition was thought to be a dominant one.

The mutation is found on the SOD1 gene, and amongst the general French bulldog population, results collated by gene testing laboratory Paw Print Genetics indicates that as many as 20.7% of the total French bulldog population may be carriers for the condition, with 5.7% considered to be “at risk.”

How can you find out the degenerative myelopathy status of your French bulldog?

Unless your French bulldog is showing symptoms of degenerative myelopathy, the only way to find out if an apparently healthy French bulldog is a carrier for or likely to be affected by degenerative myelopathy is to have them DNA tested.

Your vet will take a DNA sample from your dog and send it to the appropriate laboratory for testing, to return a result of either clear, carrier, or affected respectively. If you purchased a French bulldog from a responsible breeder since the breed’s degenerative myelopathy health testing protocol was launched in 2016, you can also ask them if they undertook pre-breeding testing on their own dogs and can tell you the status result of your dog’s parents.

Breeding and buying healthy French bulldogs

If you are considering buying a French bulldog puppy, degenerative myelopathy is one of the most important conditions to ask the breeder about when it comes to health testing. The only way to ensure that your prospective pup won’t develop the condition in later life is to choose one from a litter whose parents were tested and deemed not at risk of passing the condition onto their puppies

If you breed French bulldogs, or are considering breeding a litter from your own pet Frenchie, having both the dam and sire tested prior to breeding is the responsible decision to make, and will help your puppy buyers to avoid heartbreak and expensive vet’s bills further down the line.

Talk to your vet to find out more about getting your dog health tested, and for advice and insights on breeding healthy French bulldogs.