Des Moines Register: During hearings Wednesday, U.S. House and Senate members grilled meatpacking executives about why their profits were soaring, while at the same time, independent cattle producers are suffering significant losses. Legislators blame cattle producer losses on consolidation within the beef industry and the tremendous market power of four large meatpackers — Cargill Inc., Tyson Foods, JBS and National Beef Packing Co., which process about 80% of the nation’s cattle supply. Both Republican and Democratic senators suggested the answer could be to break up the Big Four meatpackers to regain market balance.