The typical cage for egg-laying hens allows floor space about the size of a sheet of printer paper. Such cages are stacked 3 to 9 tiers high. Japan has the world's highest battery cages stacked 18 tiers high, all in windowless sheds. Some chickens will become violent, others will go mad. A few deprived of food and hope will become cannibalistic. 97% of all eggs in the United States are from hens in battery cages with no way to roam outside. The doors of their cages will open once, at the end of their life, for their journey to the only place worse, processing.
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