Flat-faced dogs such as pugs and bulldogs have a higher risk of developing heatstroke, a new study suggests.

Also known as brachycephalic dogs, these breeds have increased in popularity in recent years, with celebrities including David Beckham, Reese Witherspoon and Love Islander Olivia Buckland leading the trend.

However, the researchers say that the rising demand for these dogs is concerning, particularly as climate change increases the severity and frequency of heatwaves.

They believe increasing numbers of these breeds combined with rising UK temperatures could lead to even more dogs suffering from the potentially fatal condition in the future.

Based on their findings, published in the journal Scientific Reports, the scientists said vets should weigh up the potential risk of heatstroke when advising owners on breed selection.

Emily Hall, lead researcher and a veterinary surgeon at Nottingham Trent University’s School of Animal, Rural and Environmental Sciences, 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.”

A team of experts at the Nottingham Trent University and the Royal Veterinary College analysed anonymised electronic records of more than 900,000 dogs across the UK, in what is thought to be the largest study of its kind.

They identified nearly 400 confirmed cases of heat-related illnesses among dogs under veterinary care but believe actual numbers may be higher as many affected with heatstroke may not be taken to see the vet.

The experts used Labrador retriever, a popular breed in the UK, as the “base” comparison breed to identify dogs at most risk from heat-related illnesses.

They found bulldogs were 14 times more likely to develop heatstroke than Labs, while French bulldogs were found to be six times more likely and pugs were twice more likely to develop the condition.

In general, flat-faced dogs were twice as likely to suffer with heatstroke, the researchers said.

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

Other dogs at most risk also include Chow Chows, Dogue de Bordeaux, Greyhound, Cavalier King Charles Spaniel, Golden Retriever and Springer Spaniel.

Being above average weight and being over two years old were also some of the factors identified by the researchers as predictors for heatstrokes.

Paula Boyden, veterinary director at Dogs Trust, said: “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 heatstroke.

“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.”