A top trainer could be kicked out of the greyhound racing industry if it's proven he used live bait to train his dogs.
SPCA is investigating Brendon Cole after receiving images in July which appear to show him tying what looks like an animal to a baiting lure.
Using live or dead animals to bait dogs is banned in New Zealand because it is considered cruel.
The Australian greyhound industry was rocked by scandal in 2014 after it emerged there was widespread live-baiting in some states.
The photos, taken from a distance, show a pair of trainers, including Mr Cole, attaching an animal-like object to a rod inside a training ring.
SPCA chief executive Andrea Midgen said the blurry photos make it hard to tell what the object was, and if it was dead or alive, but it was enough to spark an investigation.
"One of them has what looks like a white fluffy something," she said.
"The other one looks more like it could be a rabbit or a possum."
It was rare for trainers to act illegally, she said, because it was their livelihood.
"There's that balancing act between pushing things as far as they can to the edges of the law, but they don't want to lose that income stream, so it's very important they tow the line."
Ms Midgen said the SPCA was interviewing people on the property and carrying out forensic testing for animal blood at the training grounds.
Industry association Greyhound Racing New Zealand was alerted to the investigation in July.
Its chief executive, Phil Holden, said the allegations were very concerning.
The Racing Integrity Unit, the association's watchdog, monitors the industry closely, he said.
Routine checks showed there has not been any sign of the practise, Mr Holden said.
"We've never had any cause to be concerned about it."
He said the industry takes live-baiting very seriously.
"A hundred percent of them would be pretty disappointed about what's going on right now."
"We have zero tolerance," he said.
The Racing Integrity Unit will take action once the results of the SPCA investigation are known.
If the trainer is found guilty, he could be disqualified from the sport and have to pay a $10,000 fine, Mr Holden said.
RNZ could not reach the trainer for comment.