Dog shelters say they have been “flooded” with XL Bully dogs as panicked owners try to get rid of them before the ban comes into effect.
Large Breed Dog Rescue in Greenhithe, Kent, said it had put down 25 American XL Bullies last week and urged people not to panic.
It comes after Prime Minister Rishi Sunak announced last week that the breed would be banned in the UK by the end of the year, following a series of “terror” attacks.
Jo Woods, a volunteer at the rescue, said she was offered about 25 bullies a week, with owners telling her they would put their pets down if there was no space at her shelter.
“In the last week, I've put down 25 dogs and that's just me. My coordinator also liaises with specialist rescuers. They're just nuts,” he told Kent Online.
The ban follows a spate of attacks this year, including two American XL Bully dogs that allegedly killed father-of-two Ian Price in Staffordshire.
Ms Woods said some people had bought the “wrong” type of dog during the Covid-19 pandemic, which had now led to violent teenagers and untrained dogs being left at home.
Campaign group Save Our Seized Dogs said they had also been “inundated” with messages from XL Bully owners asking for help, adding that a ban would do “more harm than good”.
Campaigner Jayne Dendle said irresponsible dog owners “don't care” what happened to their dogs and would simply abandon them after the ban, making the situation worse.
In 2023, more than a third of recorded dog attacks were by American Bully breeds including the Bully XL, according to lobby group Bully Watch. The group said 341 of the 841 dog attacks it recorded in 2023 were by American Bully breeds.
Around half of American bullies bred in the UK are linked to a dog known as ‘Killer Kimbo', the lobbying group has found.
It also found that dogs associated with the animal, which grew up in Los Angeles, United States, were responsible for at least 10 violent incidents around the world.
Announcing the ban, Mr Sunak said: “American bully dog XL is a danger to our communities, especially our children.
“I share the nation's horror at the recent videos we have all seen. Yesterday we saw another suspected XL bully dog attack which tragically resulted in a fatality.
“It is not currently a statutory breed, so this vital first step must be taken quickly. It is clear that this is not a handful of spoiled dogs, it is a pattern of behavior and it cannot continue.”