Brains from cows over 30 months old at slaughter are no longer permitted in human food in the United States (Hefling, 2004). Some restaurants have taken to serving pigs' brains instead of cows' brains due to BSE concerns. But as pigs' brains are substantially smaller than cows' brains, the amount of preparation required for each sandwich increases. Each brain must be cleaned before being sliced and pigs' brains produce fewer slices.