Expert Opinions

The United Egg Producers, which represents more than 80% of egg producers in the U.S., continues to defend its promotion of barren battery cages and less floor space than a sheet of paper per bird as scientifically sound.

Yet, scientists and experts from around the world agree that this system of intensive confinement, which prevents birds from engaging in many of their natural behaviors, is inherently cruel and causes unnecessary suffering.

Below are excerpts taken from "Scientists and Experts on Battery Cages and Laying Hen Welfare," as compiled by the Humane Society of the United States.

Download entire PDF including citations.

Dr. Ian Duncan
Department of Animal and Poultry Science, University of Guelph, Canada

• "Battery cages for laying hens have been shown (by me and others) to cause extreme frustration particularly when the hen wants to lay an egg. Battery cages are being phased out in Europe and other more humane husbandry systems are being developed."
• "Hens in battery cages are prevented from performing several natural behaviour patterns. … The biggest source of frustration is undoubtedly the lack of nesting opportunity."
• "The lack of space in battery cages reduces welfare by preventing hens from adopting certain postures—such as an erect posture with the head raised—and performing particular behaviors—such as wing-flapping."
• "[T]he difficulty of inspecting cages means that the welfare of the birds is at some risk."

Dr. Joy Mench
Department of Animal Science at the University of California, Davis

• "Battery cages provide an inadequate environment for nesting, lacking both sites which fit these criteria [concealment and separation from other birds] as well as substrates for nest-building. Hens housed in battery cages display agitated pacing and escape behaviors which last for 2 to 4 hours prior to oviposition [laying eggs]."
• "Conventional cages for laying hens have pervasive problems for welfare."

Dr. Michael Baxter
Formerly with the Agricultural Engineering Unit, Scottish Agricultural College

• "The space available in a battery cage does not allow hens even to stand still in the way they would in a more spacious environment. Some behaviours are completely inhibited by confinement in a cage causing a progressive accumulation of motivation to perform the behaviours."
• "The fact that hens are restricted from exercising to such an extent that they are unable to maintain the strength of their bones is probably the greatest single indictment of the battery cage. The increased incidence of bone breakage which results is a serious welfare insult."

European Commission's Scientific Veterinary Committee

• "Battery cage systems provide a barren environment for the birds…It is clear that because of its small size and its barrenness, the battery cage as used at present has inherent severe disadvantages for the welfare of hens."

Dr. Lesley J. Rogers
Professor of Zoology, University of New England, Australia

• "In no way can these living conditions [battery cages] meet the demands of a complex nervous system designed to form a multitude of memories and make complex decisions."