Racing NSW head Peter V'landys has condemned the alleged "abhorrent actions" of the Meramist abattoir in Queensland while insisting state rules prohibit most NSW racehorses from being slaughtered at the end of their careers.
Mr V'landys said vision aired by ABC TV of racehorses being sent to slaughter was "sickening and horrendous" but such mistreatment wasn't tolerated in NSW.
"NSW is the only state in Australia that has a rule of racing that prohibits horses from being sent to a knackery or abattoir if they have been predominantly domiciled in the NSW thoroughbred racing industry," the chief executive said in a statement.
"Further, in NSW it is illegal for an abattoir to process a horse for human consumption, unlike other states."
Racing NSW on Friday called on the Queensland government and its primary industries department to take the "strongest possible" action against the alleged perpetrators at the Meramist abattoir north of Brisbane.
The ABC report also claimed 14 ex-racehorses were found at a NSW knackery.
It said Australia-wide hundreds, possibly thousands, of healthy racehorses are being sent to slaughterhouses annually.
Mr V'landys on Friday said no system was foolproof and unfortunately one per cent of participants broke the rules while everyone else did the "completely right thing".
But UNSW animal rights expert Siobhan O'Sullivan said there's been a "systemic" failure and Mr V'landys' claim that the majority of racing participants did the right thing was nonsense.
"The industry is lying to us," Dr O'Sullivan told AAP.
"It always suits industry to say it's a few bad apples - but I don't find that a credible explanation."
Dr O'Sullivan said a national horse registry would be a positive step forward but she doubts it would be a magic bullet.
"Those systems don't often work terribly well, particularly when they're just left to self-regulation," she said.
"Animals do go missing from chains like that. We've seen the same with live animal exports."
RSPCA Australia acting chief executive Bidda Jones said the ABC report highlighted the "appalling" handling and slaughter practices at the Queensland abattoir as well as the "oversupply and wastage" of horses in the racing industry.
The matter should be urgently investigated by the federal department of agriculture, Dr Jones said in a statement.
"Racing Australia and the state racing bodies need to get real.
"It's clear they have completely lost control of the way racehorses are managed in their industry, from how they are treated while training and racing, to their fate after racing."