Warning: This story contains images and descriptions that may upset some viewers.
Newshub has obtained multiple photos and descriptions of injured greyhounds linked to the South Island's most successful trainer, John McInerney.
An independent vet says the images warrant investigation, while animal rights group SAFE described the condition of the dogs as disgraceful.
McInerney oversees the largest number of racing dogs in the country.
Newshub can reveal he was recently charged by the Racing Integrity Board (RIB) for racing another dog when it had an open wound - its tail bone was exposed.
In the photos supplied to Newshub, another dog, Homebush Bayern, is seen with a large, partially-healed wound on his right shoulder, and a fresh wound on the back consistent with bite marks from another dog.
Homebush Ramona had an infected dislocated toe that had to be amputated.
Other dogs had sores on their legs. Photos of them were taken shortly after the former racing dogs were dropped off at a rehoming kennel.
Do you have more information? Email Newshub Investigations Reporter Michael Morrah in confidence at firstname.lastname@example.org
All were trained by John McInerney, although he denied that eight of his 11 dogs were in a poor condition when they arrived.
"That's not true," he said.
But Will Appelbe, SAFE investigations and rapid response manager, said the images are "seriously concerning".
"This is one of the biggest trainers in the country, he races about 200 dogs a year. Eleven dogs went to this kennel and eight of them have serious issues - that's a huge red flag."
Newshub has been leaked notes about the dogs' conditions.
Impressive Chase was 75 percent blind in one eye, "terrified of humans" and "aggressive"; Mattie Blueblood and Lonely Baxter had wounds that needed stitches; and Sozin's Comet was 6kg underweight and had severe worms.
Helen Beattie, Veterinarians for Animal Welfare Aotearoa managing director, said it warrants further investigation.
"We need more information, but certainly from the numbers coming through, the injuries seen, there absolutely needs to be further scrutiny of what's going on here."
Beattie was formerly New Zealand's chief veterinary officer and now runs an independent, science-led animal welfare company.
Her biggest concern is the marks seen on some of the dogs, which she believes are pressure sores.
"That speaks to a much more chronic, long-term husbandry issue where these animals are lying on hard surfaces for long periods of time that are causing those pressure sores," she said.
"We should be concerned about that - that's not acceptable."
Welfare rules state:
Bedding must be provided at all times and the bed must be raised off the ground
Greyhounds are to be protected from injury by other greyhounds
Immediate veterinary care must be provided for sick or injured greyhounds
John McInerney has made over $1 million so far this season and has 191 racing dogs - the largest number of any trainer in the country.
Newshub understands the injured dogs came from a property in Darfield, and that several dogs had advanced issues with worms.
Beattie said the higher the population density in an area, the harder parasites become to control.
McInerney has been charged by the RIB for failing to provide proper care for another dog, Homebush Hero, by not checking it for injury prior to racing.
Evidence at his hearing showed the greyhound's tail bone was exposed in what was described as in a "horrible state" and a days-old infection.
McInerney denied it was that bad prior to the race, saying it could have been injured in the starting box.
Newshub asked him about the photos, showing other dogs in poor condition.
"There's a picture of Homebush Bayern. How did he get those injuries?" he was asked.
"It was a dog fight," McInerney responded.
He said the injuries were "completely healed" when dropped off, although it's evident from photos the dog also had a fresh wound on its back.
"What about Ramona that had to have two toes amputated on arrival at the kennels?" Newshub asked.
"News to me," he said.
When shown that photo, he denied the injury happened at his property, saying: "It didn't come from our place like that."
Asked if he believes he's neglected his responsibilities as a greyhound trainer, McInerney said no: "That dog was not like that when it left our kennels."
But in Beattie's opinion, it's not a new injury.
"So there's a dislocated toe as well as an open wound, and the open wound would not have happened in a mere number of hours. That's a more long-standing injury," she said.
Newshub understands multiple dogs needed "immediate" vet care after being dropped off.
"It's completely shameful, It's disgraceful," said Appelbe.
"I feel for the dogs that have had to go through that kind of pain, because I think they're clear examples of neglect."
It's alleged neglect the RIB is now looking into.
RIB chief executive Mike Clement told Newshub concerns have been raised with them in relation to the photos, and the regulator is making inquiries.
"We are conducting inquiries to determine whether or not there's an allegation to be investigated," he told Newshub.
Clement said it takes such reports seriously and he would not rule out asking the SPCA to assist with its investigations.
"We reserve the right to do that."
The CEO of Greyhound Racing New Zealand refused to answer specific questions about the issue, saying it was being overseen by the RIB.
"All matters of concern of the nature you have raised are referred to the independent Racing Integrity Board for their consideration and/or investigation," she said.
John McInerney did not respond to further questions from Newshub.