<P> A concentrated animal feeding operation (CAFO), as defined by the United States Department of Agriculture (USDA) is an animal feeding operation (AFO)--a farm in which animals are raised in confinement--that has over 1000 "animal units" confined for over 45 days a year . An animal unit is "an animal equivalent of 1000 pounds live weight and equates to 1000 head of beef cattle, 700 dairy cows, 2500 swine weighing more than 55 lbs, 125 thousand broiler chickens, or 82 thousand laying hens or pullets". </P> <P> A CAFO is also an animal feeding operation of any size that discharges its waste into a waterway . For the most part, there are regulations that restrict how much can be distributed and for what the quality of the materials has to be . As of 2016 there were around 212,000 AFOs in the United States, 19,496 of which were CAFOS . </P>

Approximately how many chickens does a cafo (factory farm) house per building