A slaughterhouse or abattoir i/ˈæbətwɑr/ is a facility where animals are killed for consumption as food products. Slaughterhouses which process meat not intended for human consumption are sometimes referred to as Knacker’s yards or Knackeries.
In the United States, around nine billion animals are slaughtered every year (this includes about 150.4 million cattle, bison, sheep, hogs, and goats and 8.9 billion chickens, turkeys, and ducks) in 5,700 slaughterhouses and processing plants employing 527,000 workers; in 2009, 13,450,000 long tons (13,670,000 t) of beef were consumed in the U.S. alone. In Canada, 650 million animals are killed annually. In the European Union, the annual figure is 300 million cattle, sheep, and pigs, and four billion chickens.
Slaughtering animals on a large scale poses significant logistical problems and public health requirements. Public aversion to meat packing in many cultures influences the location of slaughterhouses. In addition, some religions stipulate certain conditions for the slaughter of animals.
There has been criticism of the methods of transport, preparation, herding, and killing within some slaughterhouses, and in particular of the speed with which the slaughter is sometimes conducted. Investigations by animal welfare and animal rights groups have indicated that in some cases animals are skinned or gutted while alive and conscious. In some cases animals are driven for hundreds of miles to slaughterhouses in conditions that often result in injuries and death en route. Slaughtering animals is opposed by animal rights groups on ethical grounds.