1949 Officers of Lancaster Livestock Exchange Convention. Bill Bixler, secretary; Walter M. Dunlap, treasurer; Jacob P. Warfel, vice president; John M. Hoober, president. 1949 Officers of National Livestock Exchange. W. P. Dolan, treasurer, South St. Paul; Christ E. Mentzer, senior vice president, Omaha; H. R. Park, secretary, Chicago; Rogers E. George, president, South St. Paul. The National Livestock Exchange was held in Lancaster in May of 1949.