12 horses, three cows, nine geese, two goats and 70 sheep among participants in Isles of Wonder-themed event

The director of the London 2012 opening ceremony, Danny Boyle, has moved to assuage concerns about the welfare of animals who will feature in his £27m show by promising to remove them from the stadium early and ensure they do not face a grisly end afterwards.

In response to concerns raised by six animal welfare groups, Boyle has sent a letter to Peta's founder Ingrid Newkirk to offer a range of assurances over plans to use live animals in his Isles of Wonder-themed opening ceremony.

After revealing earlier this month that 12 horses, three cows, two goats, 10 chickens, 10 ducks, nine geese, 70 sheep and three sheepdogs would be part of the opening scene, animal rights campaigners claimed it could breach the Animal Welfare Act by subjecting them to undue distress.

Boyle said that "genuine care will be taken of the animals" who "will feature only in the very beginning of the show during daylight hours and will leave the stadium shortly after the 9 pm start and before any large effects or noisy sequences take place".

The opening "green and pleasant" tableau is expected to give way to a more urban environment of dark satanic mills and protests.

The Slumdog Millionaire director also promised that he would "follow up vigorously" concerns about the fate of the animals after the show, to ensure they were safely retired to animal sanctuaries.

Peta said it would offer its assistance and suggested Boyle team up with fellow film director Chris Noonan, who made sure that all 48 piglets used in the making of the film Babe were spared the abattoir.

But the group said that Boyle's reply did not fully address their concerns.

"We are satisfied that the animals won't now end up in an abattoir and that much more attention is now being paid to their welfare," said a spokesman.

"But their transport and the stress of unfamiliar surroundings as well as their use as props rather than sentient, sensitive individuals have still not been addressed."

The London 2012 organising committee has insisted that "the welfare of the animals in the London 2012 Olympic Games opening ceremony is of the utmost importance". It is working with the RSPCA, which is providing animal welfare advice.

In their original letter the six groups - Animal Aid, Animal Defenders International, Captive Animals Protection Society, Compassion in World Farming, Peta and Viva - said the experience would be a "highly stressful and probably terrifying experience" for the animals.

© Guardian News and Media 2012