John Johnson, chief operating officer (COO) of the U.S. National Pork Board, speaks during an interview with Xinhua in Des Moines of Iowa state, the United States, July 27, 2018. U.S. pig farmers are feeling the pinch after the trade disputes initiated by the United States and they are worried about losing their markets, one of the heads of the U.S. National Pork Board told Xinhua in a recent interview. (Xinhua/Wang Ping)