WASHINGTON — The Department of Justice filed a civil antitrust lawsuit today in U.S. District Court in Chicago to block the proposed acquisition by JBS S.A., currently the third-largest U.S. beef packer, of National Beef Packing Company LLC, the fourth-largest U.S. beef packer. The Department said that the proposed deal would combine two of the top four U.S. beef packers resulting in lower prices paid to cattle suppliers and higher beef prices for consumers. The Attorneys General of Colorado, Iowa, Kansas, Minnesota, Missouri, Montana, North Dakota, Ohio, Oklahoma, Oregon, South Dakota, Texas and Wyoming are joining the Department’s lawsuit. JBS, headquartered in Brazil, is in the process of acquiring Smithfield Beef Group Inc. from Smithfield Foods Inc. The Department is not challenging JBS’s acquisition of Smithfield Beef Group Inc. In 2007, JBS purchased Colorado-based Swift Foods Company. Beef packers purchase annually $30 billion in fed cattle from feedlots, slaughter them, and pr...