London: More than a quarter of chickens bred intensively for meat have difficulty walking, crippled by rapid weight gain, sleep deprivation and cramped conditions, according to a study funded by Britain's farm ministry.
The study found that at an average age of 40 days, more than 27.6 per cent had difficulty walking and 3.3 per cent were almost unable to walk despite culling policies designed to remove severely lame birds from flocks.
"We have been called in to see flocks ... and they've all been on the floor and they can't move and they are dehydrating and starving to death," said Toby Knowles of Bristol University's Division of Food Animal Science.
"You just have to try and find a way to put down 25,000 birds because they are just going to die in agony otherwise," said Knowles, one of author's of the study.
Celebrity chefs Jamie Oliver and Hugh Fearnley-Whittingstall have led a campaign in Britain this year to improve the welfare standards in chicken production.
Knowles said broiler chickens had been subjected to intense genetic selection during the last 50 years, increasing growth rates by more than 300 per cent.
He said the problem was made worse by intensive rearing methods including crowded conditions and shorter dark periods during the day.
"By reducing the stocking density and letting them sleep at night rather than pretending it is a 24-hour day then they won't suffer the problems to quite the same extent but it would be greater than if they were a breed that is more closely related to the ancestral birds," Knowles said.
