Marks & Spencer will begin stocking a chicken breed said to be raised in the highest welfare conditions next week.

Devonshire Red is an organic free-range chicken produced on the Bridwell Park estate in Devon. The slow-growing birds are reared in wooden shelters regularly moved to fresh pasture, M&S said.

"The birds have the RSPCA's recommended stocking density of 30kg/m² - no other retailer has these welfare standards for their main range," said M&S animal welfare manager Mark Ranson.