Paraphrase This.

From “Our Decrepit Food Factories” by Michael Pollan
http://www.nytimes.com/2007/12/16/magazine/16wwln-lede-t.html?_r=2&oref=slogin

The Union of Concerned Scientists estimates that at least 70 percent of the antibiotics used in America are fed to animals living on factory farms. Raising vast numbers of pigs or chickens or cattle in close and filthy confinement simply would not be possible without the routine feeding of antibiotics to keep the animals from dying of infectious diseases. That the antibiotics speed up the animals’ growth also commends their use to industrial agriculture, but the crucial fact is that without these pharmaceuticals, meat production practiced on the scale and with the intensity we practice it could not be sustained for months, let alone decades.

The Union of Concerned Scientists state that over 70 percent of animals living in factory farms are fed antibiotics. Without these antibiotics, raising large numbers of pigs, chickens or cattle would simply not be possible in the filthy and confined living conditions they must live in. Livestock would constantly be dying from infectious disease. These antibiotics also speed up animal growth which is also an important trait for the agriculture industry. Without these drugs meat production as it is today could not be maintained for the future.