Trade Me is banning the sale of pugs, British bulldogs and French bulldogs because of the breathing problems suffered by the breeds.
The online auction site confirmed today that it was banning the sale of the three brachycephalic dog breeds from 1 March.
These breeds could still be listed for adoption on TradeMe and the ban extended to crossbreeds as well as purebreds.
TradeMe spokesperson James Ryan said most dogs in the banned breeds suffered from brachycephalic obstructive airway syndrome (BOAS).
"Even when the dog is not severely affected, BOAS will cause noisy breathing, snorting and snoring. However, in many dogs the symptoms are so severe that the dog will have trouble exercising (walking for longer than 3 minutes), and find it difficult to moderate their body temperature through panting and often overheat, sometimes fatally.
"As a result, it is common for BOAS sufferers to faint, vomit, cough or gag. Many dogs also have chronic sleep deprivation due to their breathing problems. The disorder has been likened to the feeling of breathing through a pillow."
He said TradeMe had not taken the decision lightly.
"We know how loved and popular these breeds are but after consultation with a range of animal experts including the New Zealand Veterinary Association and the SPCA we felt we couldn't, in good conscience, continue to allow the sale of animals who suffer lifelong health issues."
TradeMe head of trust and safety John Duffy said the move was likely to effect about 40 breeders.
"Our decision has really been based around the scientific research which suggest that regardless of whether you're an ethical breeder or an unethical breeder, 90-95 percent of all these dogs suffer these issues. So whether you are a good or bad breeder, you're breeding dogs that have these issues, and we're not willing to support that."
Mr Duffy said while the breeds were growing in popularity, there was also a growing trend away from supporting them.
NZVA chief executive Officer Mark Ward said there had been a marked increase in the supply of dogs with exaggerated features which caused serious health issues.
"Without correctional surgery, large numbers of these dogs live with chronic pain and distress, with many owners and breeders unaware that their dog is suffering."
Rochelle Ferguson from the Veterinary Association said they were seeing a lot of cases of poor health.
"These dogs aren't able to go for walks along the beach, these dogs aren't able to procreate without assistance, they can't mate or deliver their young without caesarean section. These dogs are prone to having skin problems, teeth problems, in addition to not being able to breath well. They have eye problems. It's a bit of a catalogue of misery for many of them."
And she said unfortunately many of the problems had become normalised
"We hear people say things like 'Oh yes he does make a noise when he breathes and he struggles after a short walk but that's normal for a bulldog.'
"Now we wouldn't accept that lameness is normal for a labrador so why are we accepting that the inability to breath is normal for a bulldog or a Frenchy. I think owners and breeders have just allowed the bad to become normal and that's to the detriment of these dog's welfare."
She said the association welcomed Trade Me's move but said she was not entirely convinced a ban was going to solve the problem.
"These dogs sell for thousands of dollars and the dog's best interests aren't at the heart of the reason why some of these people are breeding."
Trade Me already bans the sale of the following breeds:
American Pit Bull Terrier