It’s Not Simply Pugs—New Research IDs the Canine Breeds at Excessive Threat of Respiratory Points

All dogs are good boys and girls. But sadly, some are predisposed to all sorts of health problems. Research out this week highlights the dogs that have the hardest time even catching their breath.

Scientists examined data from hundreds of short-faced dogs in the UK. They identified several breeds with especially high rates of brachycephalic obstructive airway syndrome, including Pekingese dogs and Bulldogs. The findings show that while these dogs in general have a higher chance of breathing troubles, the prevalence can differ significantly across breeds, the researchers say.

“It remains sensible to evaluate the extent to which brachycephalic breeds are affected by health issues by their individual breed,” they wrote in their paper, published Wednesday in the journal PLOS-ONE.

Short on luck

Short-faced, or brachycephalic, dogs are defined by their flattened skulls. These skulls, while perhaps making for cute dogs, are closely associated with brachycephalic obstructive airway syndrome, or BOAS. The condition is caused by the chronic obstruction of the airways, typically the result of too much soft tissue packed inside the skull, and is characterized by symptoms like wheezing, snoring, and an inability to be active for very long.

Scientists have extensively studied BOAS and its risk factors among popular breeds infamous for their breathing problems, particularly the pug, Bulldog, and French Bulldog. But the study researchers say there’s been considerably less attention paid to how often and why BOAS can happen in other brachycephalic dogs.

In this latest study, the authors proactively studied the health of 898 dogs across 14 less studied brachycephalic breeds. These dogs, all over the age of one, were examined at veterinary appointments, dog shows, or breed-specific heath testing clinics. They compared BOAS rates among these dogs to historical data collected on pugs, Bulldogs, and Frenchies, using a four-point scale (a zero score meaning no or few symptoms).

While Bulldogs are notorious for often having BOAS, the researchers found that Pekingese dogs suffer from it just as much. About 90% of Pekingese in their study had some level of BOAS above grade zero. Japanese Chins also routinely had BOAS, with roughly 83% having some degree of it.

Many of the other breeds didn’t fare great either. The King Charles Spaniel, Shih Tzu and Boston Terrier all had rates of BOAS between 50% and 75%; and the Cavalier King Charles Spaniel, Pomeranian, Boxer, and Chihuahua had rates between 25% and 50%. Ultimately, there were only two breeds without signs of major breathing problems: the Maltese and Pomeranian.

Better breathing

The team’s work confirms that BOAS is a frequent health problem among brachycephalic dogs. And they identified several important things that seem to generally increase the risk of dogs developing it, such as an especially flattened face and narrowed nostrils (also called nostril stenosis).

On the other hand, their research also shows that not all breeds suffer from BOAS equally, and that its associated risk factors can differ between specific breeds. Some extremely flat-faced breeds, like the King Charles Spaniel, had lower rates of BOAS than the researchers expected based on their skull shape, for instance.

In recent years, there have been efforts to improve the breeding of brachycephalic dogs like the pug to reduce the risk of BOAS and other common health problems (some countries have also pushed for the outright banning of certain breeds). The researchers argue that these efforts will be tweaked on an individual breed-by-breed basis if they are to be successful. “The findings of this study advocate for a breed-specific approach when tackling the reduction of the disease on a population level,” they wrote.

Every dog deserves love and attention. Some, however, will need added help to escape the genetic fate we created for them.