The changing face of Brachycephalic Breed dogs – Bulldogs, Pugs, Frenchies & Boxers

Breeds such as Pugs, Bulldogs, French bulldogs and Boxers are prone to a range of health problems, many of which are related to their short skulls and other characteristic features.

Breeding over the years has changed skeletal structures in their skulls resulting in narrower nostrils, deformed windpipes and excess soft tissues inside their nose and throat. All of these can obstruct breathing which in turn can lead to secondary complications including regurgitation, heart disease, hiatus hernias and laryngeal collapse.

If you look at the CT image below comparing the skulls of a Brachycephalic breed and a regular long nose breed dog – you can see why the internal tissue structures can easily fill more of the available space making it harder for your dog to breathe.


Brachycephalic obstructive airway syndrome (BOAS), is estimated to affect half of all brachycephalic breed (flat-faced) dogs, most notably Bulldogs, French bulldogs and Pugs.

The degree to which individual dogs are affected varies. Most of the time owners are completely unaware of signs their dog is suffering from this condition.

Habits such a snoring, snorting and panting after even small amounts of activity are, seen as normal and sometimes even described as cute or funny. But – there’s nothing funny about a dog that is struggling to breathe.

BOAS dogs can suffer from oxygen starvation, leading to fainting and other problems. The constant fight to draw in air can also create a destructive negative pressure inside the animals. Over time, this weakens harder structures such as the larynx, causing them to narrow or even collapse, further obstructing the airway.

Their lack of ability to draw in large amounts of air quickly also means these dogs also very prone to overheating – especially during Summer.

How is BOAS in dogs Diagnosed?

If your dog is a (Bulldog, Pug, French Bulldog) then it’s most likely he or she has some degree of BOAS. This can only be accurately diagnosed by a combination of:

  1. An exercise tolerance test
  2. CT Scan of the head and internal structures and
  3. Endoscopic visualisation of the throat & airways.

Exercise Tolerance Test for BOAS

This is the first step in determining whether your dog has BOAS. Ideally this should be performed when your dog is young – preferably between 6 months and 1 year of age BEFORE signs appear.

Please note – this is not a routine consultation or heath check. The extent of BOAS can’t be diagnosed from a routine physical examination alone.

If the results indicate a positive response then a CT Scan of your dog’s head is recommended.

What a CT shows

The CT scan shows the size and shape of the soft palate, how much space it occupies in the throat and the presence of Aberrant Nasal Turbinates that will block the nasopharynx

Too often in these breeds the soft palate is longer and thicker than normal which means it blocks off space within the throat thereby limiting vital airflow to the lungs. Unfortunately the size and shape of these internal tissue structures have not changed with shrinking skulls so they are often grow far too big for the spaces they occupy.

Long Term Effects of BOAS

If they don’t become obese due to low exercise tolerance, BOAS dogs can become starved of food as well as oxygen. The fleshy throat obstructions can make eating and swallowing difficult, and this can lead to frequent regurgitation as oesophageal changes occur

  • The build – up of pressure, meanwhile, can pull at the digestive tract, drawing out fleshy folds and even pulling up the stomach into the chest, causing reflux (Hiatal Hernia)
  • Their thick soft palates are virtually closing off the airways in some dogs. These dogs are slowly choking to death!
  • Left untreated, BOAS can also cause irreversible heart damage.

These are all serious secondary conditions which can’t be reversed.

Too often we see these dogs only when they are already in a life- threatening condition such as collapse because people know so little about this condition. By the time this happens, these dogs already have developed life-threatening secondary complications.

This is why we are urging all Brachycephalic pet owners to consider early diagnosis and intervention before your dog gets to this stage.

Even if your dog is showing no symptoms – please at the very least have the exercise tolerance test performed.

What can I do to avoid BOAS complications in my dog?

Early corrective surgery can help your dog breathe better and avoid the dangerous long-term side effects of BOAS.

The corrective surgery can be staged over a period of time. The first step is surgically widening the nostril (nares) to at least allow your dog to intake air more freely. Further surgery is determined by the extent other indicators of BOAS are present.

Nasal Opening Comparison

The picture on the right shows the difference in size in nostril openings between a Brachycehpalic Breed of dog (Left image) and a long nose breed. (Right image)
You can clearly see how much smaller and narrower the opening is for these flat faced breeds.

Opening up these nares is the first corrective surgery we recommend in BOAS surgery.

The past approach to BOAS Surgery

The past approach to BOAS surgery addresses these three elements

  1. Widening Nares (Nostrils) = allows greater airflow into your dog’s lungs. Dogs naturally breathe through their nose and not their mouth
  2. Removing laryngeal saccules. Located inside the larynx
  3. Shortening the soft palate

However – the latest research shows this is no longer enough. This is due to the changes caused through breeding over the past year

New approach to BOAS Surgery based on latest research

The modern surgical approach addresses the following

They are:

  1. Stenotic nares,(Widening the nostrils to allow more airflow into the lungs)
  2. Nasal septum
  3. Deviation, aberrant nasal turbinates, Similar to adenoids in people) pushed back further out of the nasal cavity into the back of the throat. These are removed in new approach to BOAS.
  4. Soft palate elongation and hypertrophy,
  5. Nasopharyngeal mucosal hyperplasia,
  6. Tonsil hypertrophy,
  7. Macroglossia, everted laryngeal saccules and
  8. Tracheal hypoplasia

We understand that’s a lot of technical speak however it’s important to compare the differences between the original more simplistic approach to corrective surgery and what experts are saying now.

To summarise

If you own one of these lovable breeds, we strongly urge you to consider his or her long – term health by having them examined for BOAS early.

Ask for a BOAS consultation which includes the exercise tolerance test with one of our team. Email us or Message us through Facebook and we’ll organise it for you. Also if you have any more questions – please feel to reach out as well.

After that we’ll be able to tell you whether BOAS is a concern and make any further recommendations from there.

Related information from our blog

Smooshy faced dogs – What’s not to love about them.


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