5 frequently asked questions about BOAS or brachycephalic obstructive airway syndrome in dogs

5 frequently asked questions about BOAS or brachycephalic obstructive airway syndrome in dogs

Health & Safety

BOAS or brachycephalic obstructive airway syndrome is the long and rather complicated name given to a combination of conformation defects that can arise in certain specific types of dogs, and which can have a serious, acute and limiting effect on their health.

BOAS can affect a dog’s quality of life, lifestyle and even lifespan, and it can also be very time consuming and expensive for owners of dogs with BOAS to care for their dogs too, because dogs with anything other than mild levels of BOAS need to have a number of special accommodations made to reflect the limitations of their condition.

However, despite the fact that BOAS is incredibly common across many of the UK’s most popular dog breeds including the French bulldog, English bulldog and pug, every year, thousands of puppy buyers unwittingly buy a puppy that has BOAS without realising it, and having no idea of the impact that the condition can have upon both dog and owner.

The above-mentioned breeds and others with similar physical traits that can cause BOAS are hugely popular in the UK – but also, often prone to BOAS, not helped by a large number of irresponsible breeders who produce dogs of this type for looks and profit alone, rather than with the best interests of the dogs themselves in mind.

Getting objective information about BOAS when you’re trying to choose a healthy puppy isn’t always easy, and you should never simply take a breeder’s word for it that their dogs are healthy, free of BOAS, or not at risk of the condition. Nor should you take at face value any claims made by breeders about the impact of BOAS on their own breed lines, or how it might affect and limit individual dogs.

With this in mind, this article has been produced to answer five of the most basic frequently asked questions that people have about BOAS or brachycephalic obstructive airway syndrome in dogs, as part of a series of guides on the condition to help prospective puppy buyers to make healthy choices. Read on to learn more.

What does BOAS mean?

BOAS stands for “brachycephalic obstructive airway syndrome.” It is not so much one health condition as a collection of potentially several, which occur in affected dogs in varying degrees from very mild to very severe, depending on the conformation of their head and face.

Brachycephalic obstructive airway syndrome can present in different ways in different dogs, and as mentioned, to different degrees of severity. BOAS can result in a number of problems affecting the dog’s upper airways, and which are caused in their turn by the dog in question having an abnormally short muzzle and soft palate, leading to a flat-faced appearance.

BOAS is caused by conformation defects that may include any or all of the following:

  • A longer and thicker than normal soft palate.
  • Abnormally narrow nostrils.
  • Growth defects within the windpipe.
  • Everted laryngeal saccules, which obstruct airflow in the windpipe.

These conformation problems can cause issues for the dog simply breathing normally, causing discomfort, distress, poor oxygenation, and a wide range of other difficulties that can affect every aspect of the dog’s life. Being unable to breathe freely is of course frightening, uncomfortable and dangerous, and means that exercise, normal play and hot weather pose a real threat to some dogs with BOAS too.

Dogs with severe degrees of BOAS don’t have a very good quality of life and cannot take part in normal activities like vigorous play and exercise, and exertion and hot weather can directly threaten their lives and even prove fatal in some cases.

What type of dogs might have BOAS?

BOAS can occur in any dog with a brachycephalic face. A brachycephalic face is one that is shorter than the healthy norm for dogs as a species; and yet, the brachycephalic face is in fact the norm and actually desirable within certain dog breeds, which are bred to replicate this trait.

The three dog breeds mentioned in the introduction are all brachycephalic and so, might have BOAS, and some others include the Boston terrier, Cavalier King Charles Spaniel, and Boxer.

There are several others as well, so ensure you find out if the breed you’re considering is brachycephalic before you buy.

Do all brachycephalic dogs have BOAS?

Any brachycephalic dog can theoretically have BOAS, but BOAS is a condition that appears on a sliding scale in line with the flatness of the face of the dog, rather than something that is very binary in terms of yes or no, they have it or they don’t.

The degree of flatness of a dog’s face and how brachycephalic (flat faced) they are directly correlates to the level of BOAS they display.

A dog whose face is just brachycephalic to the tiniest degree, and that looks almost the same as the norm for the dog species as a whole will in turn have the tiniest degree of BOAS, which in effect will be so low as to be immeasurable, or normal.

The more acute the brachycephaly or flatness, the more acute the BOAS. Ergo, dogs with very flat faces and short soft palates will have it worst. Sadly, these are often also the dogs that are considered to be the cutest looking, most in demand with buyers and most profitable to breed, despite the impact it has on the dog’s health.

The degree to which a dog is brachycephalic varies both from breed to breed, with some brachy breeds being much more moderate on the whole than others. Variations can be significant from dog to dog within individual dogs of each breed too. Breeds strongly associated with high levels of acute BOAS like the pug and French bulldog can be particularly variable from dog to dog in terms of the length of the muzzle and so, impact it has on health.

How serious is BOAS?

How serious BOAS is depends on how badly it affects any given dog, which as explained above, depends how flat the dog’s face is.

Some dogs with BOAS have it so mildly as that it has virtually no impact on their day to day life and lifestyle, whilst for others, they will be hugely limited in more or less everything they do.

A dog with severe BOAS may struggle to breathe even when at rest, be unable to move past a walk and even then need to be kept very quiet, and overheat incredibly quickly in hot weather.

Severe BOAS is limiting, distressing and dangerous, and means affected dogs simply don’t have a good quality of life, and may even die of the condition. Very mild BOAS, on the other hand, places very few limitations on the dog in question.

Can BOAS be treated or cured?

Mild to moderate BOAS tends to be managed rather than treated, by means of avoiding very vigorous exercise, keeping the dog at a healthy weight, and taking care to keep them cool in hot weather.

The only way to ease the symptoms of a dog with BOAS that is serious enough to make their quality of life untenable is by means of surgical correction of the conformation issue causing the problem. What type of surgery this is depends on the problem or problems in play, and is not viable for every issue or every affected dog.

BOAS surgeries tend to be complex and costly to perform too, but for dogs suffering acutely in day to day life, this may be the only option to make them more comfortable and able to breathe without a continual struggle, but even after surgery their lifestyles will still tend to be somewhat limited.



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