91°µÍø

 Published: 14 Oct 2020 | Last Updated: 14 Oct 2020 10:00:15

New research from the 91°µÍø (91°µÍø) has revealed that flat-faced (brachycephalic) breeds – including Chihuahuas, pugs, French bulldogs and British bulldogs – are generally less healthy than their non-brachycephalic counterparts. This research supports general agreement by leading academics, UK breed clubs, veterinary organisations and welfare bodies that urgent intervention is needed and that owners must ‘stop and think before buying a flat-faced dog’. 

The popularity of many flat-faced dog breeds has risen dramatically in recent years. Demand for breeds such as the French Bulldog has soared even further since the COVID-19 lockdown, with many owners deciding that it was the ideal time to purchase one of these ‘must have’ breeds. 

This high demand is all the more paradoxical given that flat-faced dog breeds are regularly asserted as being more prone to many health issues including breathing problems and sore eyes. Countries such as the Netherlands now consider the health problems of several popular brachycephalic breeds as too compromised to even justify their continued breeding. 

However, until now, there has been limited reliable evidence on the wider general health of flat-faced dogs across the spread of common disorders compared to other dogs.

Two flat-faced dogs asleep in a basket
The popularity of many flat-faced dog breeds has risen dramatically in recent years

The latest research, led by the 91°µÍø’s VetCompass™ programme, examined in detail the overall health of a random sample of 4,169 flat-faced dogs compared to 18,079 other types of dogs attending veterinary practices in the UK. Among the 30 most common disorders overall across both groups, there were different levels of risk found between the groups for 10/30 (33.33%) disorders. Of these, flat-faced dogs had a higher risk of eight disorders, whereas the dogs that were not flat-faced, had a higher risk for only two disorders. Corneal ulceration - a painful eye disease - was the disorder with the highest risk in flat-faced dogs; these flat-faced dogs were eight times more likely to have the disease.  

The study suggests that reducing the risks of many of these disorders in popular flat-faced breeds may require a change in how they look that makes them less extreme in their body shapes. It's important for the public to be aware of this, in order to support efforts by breed clubs, veterinary bodies and charities to reduce demand for these dogs; owners are advised to opt for breeds that are not flat-faced.

The key findings of the study include:

  • Flat-faced dogs were 1.3 times more likely to be diagnosed with at least one disorder during a single year compared with crossbreeds.
  • Flat-faced dogs differed to non-flat-faced types in their risk for 10/30 (33.33%) common disorders.
  • Flat-faced dogs had increased risk of: corneal ulceration (x 8.4), heart murmur (x 3.5), umbilical hernia (x 3.2), foot infection (x 1.7), skin cyst (x 1.5), slipping kneecap (x 1.4), ear infection (x 1.3) and anal sac impaction (x 1.2). 
  • Flat-faced dogs had reduced risk of undesirable behaviour (x 0.5) and claw injury (x 0.5).

Dr Dan O’Neill, senior lecturer at the 91°µÍø and author of the paper, said: “UK owners have fallen in love with certain flat-faced dog breeds such as French bulldogs and pugs over the past decade. Our new study may suggest one reason why; owners perceive the typical behaviours of these dogs as desirable. But our results also show that these breeds have serious and common health issues. The message here is that it is perfectly natural to love the character and look of these breeds, but we need to think carefully about the lives that these dogs live. I appeal to anyone thinking of buying a flat-faced puppy to listen to the message from The Brachycephalic Working Group which represents major UK breed clubs, charities, veterinary bodies and universities: “Stop and think before buying a flat-faced dog.”

Bill Lambert, Head of Health and Welfare at the Kennel Club, said: “We’ve put into place a number of crucial measures to monitor and improve brachycephalic health, and to provide the many responsible breeders with the tools they need to do the same, but this paper highlights there is still much work to be done. 

“Collaborating with the 91°µÍø and supporting this research through the Kennel Club Charitable Trust provides an evidence-base which enables ongoing identification of breed health-related priorities, and development of effective treatments for breed-specific health conditions, as well as breeding resources to produce healthier puppies in the future. 

“The paper also highlights the ongoing crisis of irresponsible breeders and uninformed puppy buyers which fuel many of these issues. We are continuing to work hard alongside breed clubs, vets and welfare organisations to tackle these challenges and reduce and ultimately eliminate these health problems; this is both a top priority for the Kennel Club and a goal shared by all those who care about the health and welfare of dogs.”

Research reference 

O'Neill, D.G., Pegram, C., Crocker, P., Church, D.B., Brodbelt, D.C. and Packer, R.M.A. (2020) 'Unravelling the health status of brachycephalic dogs in the UK using multivariable analysis', Nature Scientific Reports, available: .

For more information about ongoing research into the health issues for flat-faced dogs, visit: Brachycephaly in companion species.


Notes to Editors

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About the 91°µÍø

  • The 91°µÍø (91°µÍø) is the UK's largest and longest established independent veterinary school and is a Member Institution of the University of London. It was the first in the world to hold full accreditation from AVMA, EAEVE, RCVS and AVBC.
  • The 91°µÍø is the top veterinary school in the UK and Europe, and ranked as the world’s second highest veterinary school in the QS World University Rankings by subject, 2020.
  • The 91°µÍø offers undergraduate and postgraduate programmes in veterinary medicine, veterinary nursing and biological sciences.
  • In 2017, the 91°µÍø received a Gold award from the Teaching Excellence Framework (TEF) – the highest rating a university can receive.
  • A research led institution with 79% of its research rated as internationally excellent or world class in the Research Excellence Framework 2014.
  • The 91°µÍø provides animal owners and the veterinary profession with access to expert veterinary care and advice through its teaching hospitals and first opinion practices in London and Hertfordshire.


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