Apparently, researchers have discovered that caged hens are no more stressed than those that roam free.
Corticosterone, a hormone produced in response to stress or fear, was measured in eggs from free-range and caged hens. Results showed that the levels of this hormone in both free-range and caged eggs were very similar.
According to Jeff Downing, who led the research at Sydney University, free-range hens suffer stresses that battery hens do not have to deal with. “If they have no cover they are constantly in fear of attack by predators,” he explained. “You can see it. A shadow comes over and they are completely startled.”
Downing said that free-range hens are also exposed to manure-borne diseases and parasites. He added that extreme temperatures are more stressful to hens than the method of their housing, and that caged hens have greater protection from both the elements and predators.
However, many disagree. Additionally, the numbers of free-range egg sales are on a steady increase, and caged hens are becoming fewer.
Julia Wrathall, head of the RSPCA’s farm animal department, said the research contrasted with a number of other studies that have suggested that caged birds suffer more than free-range hens. “The RSPCA believes, and scientific evidence shows, that battery cages are simply unacceptable because they don’t adequately satisfy the hens’ basic behavioural and physical needs,” she said.