Beef is the culinary name for meat from cattle. In prehistoric times, humans hunted aurochs and later domesticated them. Since then, numerous breeds of cattle have been bred specifically for the quality or quantity of their meat. Today, beef is the third most widely consumed meat in the world, after pork and poultry. As of 2018, the United States, Brazil, and China were the largest producers of beef. In the United States, beef production has come to rely heavily on factory farms. The prevalence of manure in these farms has been linked to contamination of beef with E. coli, leading to large recalls, as well as increased antibiotic usage. The now-restricted use of meat and bone meal feed was historically responsible for outbreaks of bovine spongiform encephalopathy.