Cambridge, UK – Researchers at the University of Cambridge uncovered widespread breathing difficulties in 14 brachycephalic dog breeds, challenging the notion that issues like brachycephalic obstructive airway syndrome, or BOAS, afflict only pugs, bulldogs, and French bulldogs.
Pekingese and Japanese Chin Match High-Risk Profile
Nearly 90 percent of Pekingese dogs examined showed signs of BOAS, with just 10.9 percent achieving the top respiratory grade of zero, indicating free breathing during exercise. Japanese Chin followed closely, affecting 82 percent of the group, where only 17.4 percent breathed without obstruction.
These rates rival those in the traditionally flagged breeds: pugs at around 7 percent grade zero, French bulldogs at 10 percent, and bulldogs at 10.9 percent. The team assessed 898 dogs over three years using a standardized three-minute trotting test adapted from prior protocols. Lead author Dr. Francesca Tomlinson noted, “BOAS exists on a spectrum. Some dogs are only mildly affected, but for those at the more severe end, it can significantly reduce quality of life.”
Severe cases manifest as labored breathing, exercise intolerance, and overheating, often requiring surgical intervention.
Full List of Breeds Under Scrutiny
The investigation targeted these 14 breeds in the UK pet population:
- Affenpinscher
- Boston Terrier
- Boxer
- Cavalier King Charles Spaniel
- Chihuahua
- Dogue de Bordeaux
- Griffon Bruxellois
- Japanese Chin
- King Charles Spaniel
- Maltese
- Pekingese
- Pomeranian
- Shih Tzu
- Staffordshire Bull Terrier
Researchers categorized risks: high for Pekingese and Japanese Chin; moderate for Griffon Bruxellois, Boston Terrier, Dogue de Bordeaux, King Charles Spaniel, and Shih Tzu; mild for Staffordshire Bull Terrier, Cavalier King Charles Spaniel, Chihuahua, Boxer, and Affenpinscher. Maltese and Pomeranian showed no clinically significant issues.
Surprisingly, some extremely flat-faced breeds like King Charles Spaniel performed better than expected, highlighting breed-specific variations.
Conformation Traits Fuel the Problem
Across breeds, three factors stood out: elevated body condition scores signaling overweight status, nostril stenosis where nostrils collapse inward, and reduced craniofacial ratios marking flatter faces. These traits explained about 20 percent of BOAS variation in a logistic regression model.
Other contributors varied: thicker necks plagued Boston Terriers and Staffordshire Bull Terriers, while shorter tails raised risks in Shih Tzus and Staffordshire Bull Terriers. Dr. Jane Ladlow emphasized, “Weight loss could be used as a management tool to reduce the risk of BOAS in these breeds, as it is in the Pug.”
| Risk Level | Example Breeds | % Grade 0 |
|---|---|---|
| High | Pekingese, Japanese Chin | ≤25% |
| Moderate | Shih Tzu, Boston Terrier | 25-50% |
| Mild | Boxer, Chihuahua | >50% |
Path Forward for Healthier Breeding
The findings, detailed in PLOS One, urge tailored strategies per breed rather than blanket measures. Tomlinson advocated, “Our findings support a breed-specific approach when tackling the reduction of this disease on a population level.”
Breeders and judges should prioritize respiratory health screenings, avoiding rewards for extreme traits like pinched nostrils. Owners can mitigate risks through weight control and awareness.
Key Takeaways
- Pekingese and Japanese Chin face BOAS rates akin to pugs and bulldogs.
- Overweight, narrow nostrils, and flat faces drive most risks.
- Breed-specific breeding and management offer the best welfare gains.
This research signals a pivotal shift toward prioritizing breath over beauty in dog breeding. What steps will you take if you own one of these breeds? Tell us in the comments.
