DutchNews.nl reports that the group visited 10 outlets of the 10 biggest supermarket groups. It found the fast-reared broiler chickens – known as plofkip, or exploding chickens because of the way they are reared – accounted for well over half the chicken on sale in every one. In one supermarket, 95 per cent of the chicken on sale was plofkip.

The worst performers were Dirk, Jumbo and Emté. Market leader Albert Heijn, Aldi and C1000 were regarded as average. The Coop, Plus, Lidl and Deen had the greatest variety of chicken, including organic meat and meat with up to three Beter Leven stars.

In 2013, representatives of supermarkets, abattoirs and poultry farms agreed that from 2015, chickens reared for Dutch supermarkets will be of a slower-growing breed. They will be given 10 per cent more space, six hours sleep instead of just four and have straw and grain to 'play' with.

The change-over should be complete by 2020, although the plofkip will still be reared for export. Only some 30 per cent of the chicken produced in the Netherlands is for the domestic market.