A member of the public discovered the carcasses on Tuesday in the Wild Flower Reserve on Coonarr Beach Road in Coonarr.

They were in varying states of decomposition.

The police and RSPCA joint greyhound racing inquiry task force are now investigating.

RSPCA spokesman Michael Beatty said it was believed the dogs were killed before the Four Corners special on live-baiting in the greyhound racing industry was aired on February 16.

"Unfortunately as I think most people would be aware, there's always been a lot of wastage in the greyhound industry," he said.

"The indications are that these may just be young dogs that didn't have the speed, basically. But that's really all we know."

Bobby Etheridge from the Friends of the Hound greyhound rescue group said the dumping of unwanted dogs was sad but not surprising news.

"It's horrible, and really shocking to those who don't know about it, but it's everyday business in the greyhound world," she said.

"We have been trying to tell people this for years, but it falls on deaf ears every time because there's too much money involved."

Autopsies will be carried out to determine the cause of death, and the dogs' ages.

Queensland Police Minister Jo-Ann Miller took to social media to say she was "absolutely sickened" by the news.

"Animal cruelty in Queensland won't be tolerated," she said.

Absolutely sickened that @QPSmedia & @RSPCAQld have found the remains of 55 greyhounds. Animal cruelty in Qld won't be tolerated. — Jo-Ann Miller (@JoAnnMillerMP) April 1, 2015

Racing Queensland CEO Darren Condon described the discovery as "a despicable circumstance".

"We'll seek a formal report from the police," he said.

"We'll obviously work with police to assist in their investigations and take the appropriate response."

Mr Condon said he hadn't previously seen anything to indicate "a mass dumping of dogs".

Police have urged anyone with information to contact Crime Stoppers on 1800 333 000.

- with Jorge Branco