The use of antibiotics in farm animals is massive. As of 2009, the USDA reports nearly 30 million pounds of antibiotics—80 percent of our nation's supply—are given to animals as preventative measures to ward off illness and infections that frequent the dense and dirty concentrated animal feed operations home to tens of thousands of animals, leading to antibiotic resistant bacteria entering the food supply and rendering common treatment measures ineffective.

Grist.org senior food and agriculture writer, Tom Philpott, recently reported in an article titled, "Time to end the insane practice of lacing chicken feed with arsenic", that it's a standard chicken industry practice to dose birds with arsenic.