Battery cage

Battery cages are a housing system used by factory farms for various animal production methods, but primarily for egg-laying hens.

[1][2][3] They reduce aggression and cannibalism among hens, but are barren, restrict movement, prevent many natural behaviours, and increase rates of osteoporosis.

[4] In the United Kingdom, statistics from the Department for Environment, Food and Rural Affairs (DEFRA) indicate that 50% of eggs produced in the UK throughout 2010 were from cages (45% from free-range, 5% from barns).

[9] Battery cages are also used for mink, rabbit, chinchilla and fox in fur farming, and most recently for the Asian palm civet for kopi luwak production of coffee.

Arndt also mentions the use of conveyor belts under the cages to remove manure, which provides better air control quality and reduces fly breeding.

The wire floor allowed the manure to pass through, removing it from the chicks' environment and reducing the risk of manure-borne diseases.

At the end of this year, it was found that the birds confined in the batteries outlaid considerably the same size flock in the regular houses.

The birds consume less feed than those on the floor and this coupled with the increased production made them more profitable than the same number of pullets in the laying house.

[10]A number of progressive poultrymen from all over the United States and some in foreign countries cooperated with me in carrying on experimental work with this type of battery and each and every one of them were very well satisfied with the results obtained.

[13] By all accounts, a caged layer facility is more expensive to build than high-density floor confinement but can be cheaper to operate if designed to minimize labor.

[14] Efforts are being undertaken to prohibit battery cages in countries around the world, including Bhutan, India, Brazil, Costa Rica, and Mexico.

During 2013 the state government of Tasmania was planning to phase out battery cages and budgeting for financial compensation for affected farmers but this was scrapped following the 2014 election.

[19] In 2019, New South Wales Legislative Council member Emma Hurst established and chaired a NSW Parliamentary Inquiry into the Use of Battery Cages for Hens in the Egg Production Industry.

[23] Activist group Mercy for Animals was pleased with the announced phaseout, but called the timetable "simply outrageous" and argued that more urgency was required; some food companies such as Cara Foods, Tim Hortons, Burger King, McDonald's, Wendy's, Starbucks, and Subway restaurant announced they would phaseout non-cage-free eggs much sooner than 2036.

[38] Michigan's ban of battery cages and the sale of non-cage-free eggs in the state, adopted in November 2019, will enter into force at the end of 2024.

Animal rights groups have used videos of live chicks being placed into macerators as evidence of cruelty in the egg production industry.

[46] Maceration, together with cervical dislocation and asphyxiation by carbon dioxide, are all considered acceptable methods of euthanasia by the American Veterinary Medical Association.

In countries with relevant legislation, floor space for battery cages ranges upwards from 300 square centimetres (47 sq in) per bird.

Animal welfare scientists have been critical of battery cages because of these space restrictions[56] and it is widely considered that hens suffer boredom and frustration when unable to perform these behaviours.

To reduce the harmful effects of feather pecking, cannibalism and vent-pecking, hens in battery cages (and other housing systems) are often kept at low light intensities (e.g. less than ten lux).

Several studies have indicated that toward the end of the laying phase (approximately 72 weeks of age), a combination of high calcium demand for egg production and a lack of exercise can lead to osteoporosis.

This involves complete withdrawal of food (and sometimes water) for seven to fourteen days[63] or sufficiently long to cause a body weight loss of 25 to 35 percent.

[66] Free-range egg producers can limit or eliminate injurious pecking, particularly feather pecking, through such strategies as providing environmental enrichment, feeding mash instead of pellets, keeping roosters in with the hens, and arranging nest boxes so hens are not exposed to each other's vents;[66] similar strategies are more restricted or impossible in battery cages.