Hundreds of lambs lined up to run down Queen Street in central Auckland to celebrate the Rugby World Cup have been slaughtered.

Real New Zealand Festival organisers wanted to run about 1000 lambs from Aotea Square to Queens Wharf at lunchtime just days before the rugby World Cup final on October 17.

The run was canned when the SPCA complained it went against "humane principles".

Organiser Steve Hollander this morning said most of the lambs that were going to participate in the event had been sent to the meatworks.

They would have been kept alive for at least two extra months if the run had not been called off, he said.

"Right now they'd still be alive. They'd be getting ready for their run down Queen Street and I think they'd be having a good time."

"Taking them down Queen Street would probably have been the day of their lives and would have prolonged their lives for two months."

SPCA national chief executive Robyn Kippenberger told 3 News the lambs were destined to die regardless of whether the run was staged.

She earlier said the run would have stressed the lambs and inappropriately used animals for entertainment.

"This runs against the humane principles held by the SPCA around the use of animals for entertainment. If animals are likely to suffer, simply as a side show, then the SPCA believes that they should not be subject to this distress," she said.