... One of the most troubling things about factory farms is how cavalierly they flout these evolutionary rules, forcing animals to overcome deeply ingrained aversions. We make them trade their instincts for antibiotics.
Though the industrial logic that made feeding cattle to cattle seem like a good idea has been thrown into doubt by mad cow disease, I was surprised to learn it hadn’t been discarded. The FDA ban on feeding ruminant protein to ruminants makes an exception for blood products and fat; my steer will probably dine on beef tallow recycled from the very slaughterhouse he’s headed to in June. (“Fat is fat,” the feedlot manager shrugged, when I raised an eyebrow.) Though Poky doesn’t do it, the rules still permit feedlots to feed nonruminant animal protein to ruminants. Feather meal and chicken litter (that is, bedding, feces, and discarded bits of feed) are accepted cattle feeds, as are chicken, fish, and pig meal. Some public health experts worry that since the bovine meat and bonemeal that cows used to eat is now being fed to chickens, pigs, and fish, infectious prions could find their way back into cattle when they’re fed the proteins of the animals that have been eating them.
Source: The Omnivore's Dilemma: A Natural History of Four Meals (Large Print Press), Pages: 76
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