In the UK, vet are warning people against buying 'flat-faced' dogs:
Pugs, bulldogs, French bulldogs, shih-tzus and cavalier King Charles spaniels have become sought-after in the UK, despite wide-ranging health problems.
Their appeal is attributed to having "squashed" faces and wrinkled noses.
The British Veterinary Association said the surge in popularity of these dogs had "increased animal suffering".
Sean Wensley, president of the British Veterinary Association (BVA), said: "Prospective owners need to consider that these dogs can suffer from a range of health problems, from eye ulcers to severe breathing difficulties.
"We strongly encourage people to choose a healthier breed or a crossbreed instead."
The warning has been echoed by the PDSA, the Royal Veterinary College, the RSPCA and the Kennel Club.
...A recent survey by the Royal Veterinary College suggests many owners of brachycephalic dogs are not aware of the common underlying health problems.
Caroline Reay, chief vet at Bluecross Animal Hospital in Merton, said: "Most owners - and some vets - think airway noise, and consequently reduced activity, is normal, so the problems are rarely discussed.