Factory farming began in the 1960s when scientists realized that agriculture was going to have to become much more efficient to feed an exploding human population. Instead of small farms raising pigs outdoors in pastures, larger farms started raising them in extreme confinement, indoors. As the U.S. Environmental Protection Agencyexplains:
There has also been a significant change in how and where hogs are produced in the U.S. over the past 50 years. Low consumer prices, and therefore low producer prices, have resulted in larger, more efficient operations, with many smaller farms no longer able to produce pigs profitably.
Pigs are cruelly abused on factory farms from the time they are little piglets. Piglets routinely have their teeth clipped, have their tails cut off and are castrated without anesthesia.
After weaning, the piglets are put in crowded pens with slotted floors for the manure to fall through, into a manure pit. In these pens, they each typically haveonly three square feetof room. When they become too large, they are moved to new pens, also with slotted floors, where they have八平方英尺空间。由于拥挤，疾病的传播是一个恒定的问题，并且整个动物的动物被给予抗生素作为预防措施。当他们达到250-275磅的屠宰体重时，大部分大约五到六个月的时候，大多数都被派去屠宰，而少数女性成为繁殖母猪。
After being impregnated, sometimes by a boar and sometimes artificially, breeding sows are then confined in gestation stalls that are so tiny, the animals cannot even turn around. Gestation stalls are considered so cruel, they have been banned in several countries and in several U.S. states, but are still legal in most states.
而有些人呼吁更人道的待遇of the pigs, allowing the pigs to roam on pastures would make animal agriculture even more inefficient, requiring甚至更多的资源.
Animal agriculture is inefficient because it takes so much more resources to grow crops to feed to pigs than it would be to grow crops to feed to people directly. It takes aboutsix pounds of feedto produce a pound of pork. Growing those extra crops requires additional land, fuel, water, fertilizer, pesticides, seeds, labor, and other resources. The extra agriculture will also create more pollution, such as pesticide and fertilizer runoff and fuel emissions, not to mention the methane that the animals produce.
猪也产生了很多粪便，而工厂农场已经提出来了详细制作系统for storing solid or liquid manure until it can be used as fertilizer. However, these manure pits or lagoons are environmental disasters waiting to happen. Methane sometimes becomes trapped under a layer of foam in a manure pit and explodes. Manure pits can also overflow or can become flooded, polluting the groundwater, streams, lakes and drinking water.
Pork and Human Health
因为猪现在被养育是瘦的，所以猪肉并不像曾经是不健康的，而不是健康食品。因为它们在饱和脂肪中很高，所以哈佛大学公共卫生学院recommends avoiding red meats, including beef, pork, and lamb.
Aside from the risks of eating pork, supporting the pork industry means supporting an industry that endangers public health and not just the health of people who choose to eat pork. Because the pigs are constantly given antibioticsas a preventive measure，行业促进了崛起和传播抗生素抗性菌株of bacteria. Similarly, the pork industry spreads swine flu, or H1N1, because the virus mutates so quickly and spreads quickly among closely-confined animals as well as to farmworkers. The environmental issues also mean that pig farms endanger their neighbors' health with manure and disease.