@Wen I expect their intensive inhumane feedlot system of mass produced beef is almost certain to reduce animal health and the density of the 'herds' almost guarantees any infections will pass swiftly through the herd.
And their given hormone supplements to grow faster.
Why anyone thinks US beef is good, totally baffles me. The pollution it causes is enormous. Free ranging big herbivores are an environmental plus, but force fed dense collections are a disaster waiting to happen.
Wen