What French bulldog owners need to know about BOAS or brachycephalic obstructive airway syndrome

BOAS or brachycephalic obstructive airway syndrome is the term given to a range of different problems that affect a dog’s upper airway, and that can occur in dogs with a shortened muzzle and flat face – like the French bulldog.

Any dog with a brachycephalic face may suffer from brachycephalic obstructive airway syndrome, and the condition is not exclusive to French bulldogs. However, because French bulldogs are such a popular breed in the UK today and because many dogs of the breed are deliberately bred for a very flat-faced appearance, the condition has become prevalent within the breed to quite an alarming extent.

Not all first-time French bulldog buyers are aware of the potential risk factors that accompany a flat or brachycephalic face, nor the fact that the risks rise exponentially as the degree of exaggeration of the dog’s facial features increases.

In this article we will look at brachycephalic obstructive airway syndrome or BOAS in the French bulldog in more detail, to assist both existing French bulldog owners and potential puppy buyers in understanding the condition. Read on to learn more.

What is BOAS?

BOAS or brachycephalic airway syndrome is not so much one condition, but a combination of conditions or problems that can all be caused by an exaggeratedly flat face.

BOAS is caused by a combination of up to four congenital abnormalities that can be found in brachycephalic dogs depending on how flat their faces are, and they are:

• An elongated soft palate.
• Stenotic nares (narrow nostrils).
• Hypoplastic trachea (a growth abnormality in the cartilage of the windpipe).
• Everted laryngeal saccules, which can obstruct the dog’s airway.

All of these factors either alone or in combination can affect the dog’s ability to breathe normally and get enough air, which tends to become particularly acute if the dog is hot, exercising hard, or under stress.

Dogs with BOAS may not be able to get enough breath, and so, don’t get enough oxygen in their bloodstream and are unable to exhale sufficient carbon dioxide. This leads to panting and an increased heart rate which in turn, raises the dog’s stress levels and exacerbates the problem, which can ultimately prove life threatening.

Why is BOAS a risk to French bulldogs?

By no means all French bulldogs suffer from BOAS, but a significant number of dogs of the breed do to some extent. Dogs that have a healthy-length muzzle and whose faces are not overly flat are those most likely to be healthy, whilst dogs with very short muzzles and flat faces are much more likely to be diagnosed with BOAS.

How acute the condition is also depends on the degree of flatness of the face, and dogs of the breed that are deliberately bred for an exaggerated appearance and a very short muzzle are very likely to suffer with BOAS as a result.

The symptoms of BOAS in French bulldogs

Many French bulldogs snore when asleep, but laboured, loud or heavy snoring is one potential indicator of BOAS. Affected dogs may also have loud or laboured breath sounds when awake, particularly if exercising or when the weather is hot. Dogs whose breathing is noisy even at rest are almost certainly displaying symptoms of BOAS.

French bulldogs with BOAS will also tend to have a low tolerance for exercise, becoming worn out and panting heavily very quickly. They will also tend to overheat faster than other dogs, and be less tolerant of hot weather, particularly when exercising.

It takes them longer to cool down when hot or after exercise too, and the dog may pant for a long time after they stop moving around or move somewhere cooler.

BOAS can lead to heatstroke very easily, as well as exercise-induced collapse, both of which are serious and life-threatening conditions.

What can be done about BOAS?

In dogs who suffer from BOAS to a great extent and who are considered to be at particular risk for acute problems, or whose quality of life is significantly affected, surgical intervention is widely considered to be the only option to attempt to correct the conformation issues that cause BOAS and provide the dog with a good and safe quality of life.

Exactly what type of surgery is indicated will depend on the combination of conformation defects that cause the condition, and may include surgery to remove excess tissue from an elongated soft palate, widening the nostrils, and removing everted laryngeal saccules.

However, none of these surgeries are without risk, and in particular, corrective surgery for an elongated soft palate is not a procedure to be undertaken lightly. That said, laser surgery is now offered in some UK veterinary referral clinics, which helps to reduce the risk factors for such corrective surgeries, and shorten the recovery time too.

In dogs who suffer from a mild presentation of BOAS, lifestyle and management changes is often preferable to surgery. This will involve keeping the dog at a healthy weight as obesity can greatly exacerbate the condition, avoiding heat, keeping the dog calm, and monitoring exercise carefully.

Using a harness rather than a collar and lead is also strongly recommended for dogs with BOAS, to reduce pressure on the already compromised airway.

Choosing and buying a healthy French bulldog

If you’re considering buying a French bulldog and the health and quality of life of your new dog is your main concern, it is important to choose a dog that is bred for health and not exaggerations.

The flatter the dog’s face and the shorter their muzzle, the greater the risk factors for BOAS in the French bulldog.

Look for a dog with nostrils that are wide enough to allow them to breathe normally, and steer clear of overly stocky French bulldogs and those with exaggeratedly flat faces.

Examine the pup’s dam (and sire too, if possible) to get a better idea of the shape of the face that any puppy might be apt to display when they are fully grown.