Trendy flat-faced dogs such as bulldogs, pugs and French bulldogs are twice as likely to suffer from heat stroke than other breeds, a study shows.
Scientists found extreme selective breeding for flat faces has made it almost impossible for them to cool down.
Dogs do not sweat like humans and therefore rely heavily on panting to lower their body temperature.
But brachycephalism — having a short and wide head — in dogs makes this process far less effective, experts have found.
Just 20 minutes in a car can see them develop heat stroke, and it can be fatal to dogs. One in seven canines diagnosed with the condition dies as a direct result.
Trendy flat-faced dogs such as bulldogs, pugs and French bulldogs are twice as likely to suffer from heat stroke than other breeds, a study shows. Scientists found extreme selective breeding for flat faces has made it almost impossible for them to cool down
Pugs (pictured) had a short-lived spike in popularity due, in part, to their popularity on social media. The dog’s extremely squashed face is the result of years of selective breeding which has led to a range of health issues, including leaving them at greater risk of heat stroke
Researchers from Nottingham Trent University and the Royal Veterinary College looked at anonymous data from almost one million dogs in the UK.
These veterinarian records included more than 1,200 instances where dogs had received treatment for heat stroke.
Overall, the data reveals that flat-faced dogs are at twice as much risk of suffering from heatstroke as their long-snouted brethren.
However, some breeds are at even more significant risk.
The English bulldog, for example, is 14 times more likely to get heat stroke than a Labrador, which was found to be at no greater risk than cross-breeds and used as the experiment’s control.
Other flat-faced dogs at increased risk include the French bulldog (6x), Dogue de Bordeaux (5x) and the pug (3x).
Emily Hall, lead researcher and a veterinary surgeon at Nottingham Trent University, said: ‘It’s likely that brachycephalic dogs overheat due to their intrinsically ineffective cooling mechanisms.
‘Dogs pant to cool down – without a nose, panting is simply less effective.
‘In fact, brachycephalic dogs may even generate more heat simply gasping to breathe than they lose by panting.’
As well as brachycephalism, other factors can increase a dog’s risk of developing heat stroke.
The Chow Chow, which is a staggering 17 times more likely to suffer from the condition, and Golden Retriever breeds are also at increased risk due to their fur.
These pets have so-called ‘double-coats’ which allows the fur to trap air against the body, like goosebumps in humans.
However, this is far more effective in dogs than it is in humans due to their thick fur, and as a result, it significantly restricts their ability too cool down in hot weather.
Meanwhile, racing Greyhounds are four times more likely to suffer heatstroke because of their high lean muscle mass, which has been associated with increased risk of overheating after exercise.
Overall, the data reveals that flat-faced dogs are at twice as much risk of suffering from heatstroke as their long-snouted brethren. However, some breeds are at even more significant risk. The English bulldog (pictured), is 14 times more likely to get heat stroke than a Labrador
As well as brachycephalism, other factors can increase a dog’s risk of developing heat stroke. The Chow Chow, for example, is a staggering 17 times more likely to develop the condition due to its thick, double-layered, fur
Dog owners fall out of love with flat-faced pup
Pugs, French bulldogs and bulldogs are dipping in popularity, as miniature Dachshunds look set to overtake them as the UK’s top tiny dog by the end of the year.
This is according to registration statistics released by dog welfare organisation the Kennel Club.
The statistics have been welcomed by health and welfare experts who say that flat-faced – or brachycephalic – dogs can suffer from a number of health problems such as breathing and eye conditions due to their short head.
‘The dropping registrations for these key flat-faced breeds are a step in the right direction and we do welcome them, although with some caution,’ said Dan O’Neill, Chair of the Brachycephalic Working Group, which is made up of vets, national animal welfare organisations, scientists, and dog breed clubs.
‘We hope this is a sign that more puppy buyers, owners and breeders are considering the health and welfare implications these dogs can face, especially if these dogs are bought on an impulse solely because they ‘look cute’ but with little understanding of their potential health issues, or that they are bred indiscriminately to meet demand.’
Not the top tiny dog anymore. French bulldogs are on their way down: there were eight per cent fewer registrations of French Bulldogs in the first six months of 2019
Heavy dogs, above average weight either due to obesity or muscle mass, are also at increased risk.
Dogs that are bigger than standard for their breed are almost one and a half times more at risk than smaller animals of the same breed.
In extreme cases, when the dog weighs more than 110lbs (50kg), the average weight of a 14-year-old human, the risk soars.
These larger animals are 3.5 times at much at risk of heat stroke compared to lap dogs weighing up to 22lbs (10kg).
Dr Dan O’Neill, co-author and senior lecturer in companion animal epidemiology at The Royal Veterinary College, said: ‘As the UK moves progressively towards higher average temperatures due to global warming effects, we all need to wake up to the changing health hazards that our dogs will increasingly face.’
The authors of the study urge people to reconsider buying dogs which have been deliberately bred to have an abnormally short nose.
Previous research has found brachycephalic suffer from an array of health concerns.
Many suffer from Brachycephalic Obstructive Airway Syndrome (BOAS) which can lead to a lac of air into their lungs, and can be spotted by loud breathing; snoring; and regular, heavy panting.
They have also been found to have difficult breeding and giving birth as well as a preponderance of ailments affecting their hearts, teeth, skin and eyes.
Dr O’Neill says: ‘Knowledge is power when it comes to protecting our beloved dogs.
‘A core message from this study would be to ‘stop and think before buying a flat-faced dog’.’
Charity Dogs Trust supported the research, which was published today in the journal Scientific Reports, and Paula Boyden, veterinary director there, says owners need to be attentive to prevent their beloved dog falling sick.
‘Dogs are unable to regulate their body temperature as well as humans do, so as the weather warms up, we need to be alert to the signs of heat stroke,’ she says.
‘These findings show that owners of flat-faced breeds and dogs who are overweight, need to keep an especially close eye on their beloved pet during the warm weather as they could be at greater risk.
‘The good news is there are lots of things we can do to make sure our dogs stay happy and healthy in hot weather, whether outside or playing indoors as many of us are at the moment.
‘Make sure they have plenty of shade and water, and if you need to head out in the car with your dog, please be very careful.
‘As little as twenty minutes can prove fatal if a dog is left alone in a car on a warm day.’