Posted: June 16, 2017
Paul Patterson, professor of poultry science, said very few hens are given feed containing animal products, as was done more often in the past.
Producers used to feed hens more animal by-products. But that practice fell out of favor around the time of mad cow disease in the 1990s, according to Patterson.
Today, most commercial egg-laying hens are fed a vegetarian, corn-and-soybean-based diet, he explained, even though they are not naturally vegetarians.
--American Public Media "Marketplace," Nov. 29, 2016