And, in farming communities, a variety of protein sources were readily available, from soybeans or peanuts or cottonseed. Or, from chicken feces, poultry feathers, cow blood or other parts of pigs, horses, fish, cattle and just about any animal part unfit for human consumption.
"These days, anytime you find an animal raised in a factory feedlot setting, they're all eating rendered animal parts." Lyman said. "I was told this was the new modern way to do it. I bought into it hook, line and sinker. And I was wrong."
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Cows are still allowed to eat feeds that can include parts of pigs, fish, chicken, horses, even cats or dogs. And some of those animals -- before being rendered and mixed up for cattle feed -- are raised on food containing the same cow parts now banned from cattle consumption
And cattle can continue to consume pig and horse blood for protein, as well as tallow, a hard fat from rendered cattle parts, as a fattening source. - Seattle Post-Intelligencer
