Contentedly pecking seed in the open countryside, free-range hens have carefree lives that their counterparts in battery farms can only dream about, or so it has long been believed.
In fact, caged hens are no more stressed than those that roam free, researchers have discovered.
Scientists measured corticosterone, a hormone produced in response to stress or fear, in eggs from free-range and caged hens. They found that the levels in both were very similar.