1. Haskell County Animal Hospital, Sublette, KS (Hessman, Sjeklocha)
2. Department of Veterinary Pathobiology (Fulton, Johnson), Oklahoma Animal Disease Diagnostic Laboratory (Johnson) College for Health Sciences, Oklahoma State University, Stillwater, OK
3. U.S. Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Ames, IA (Ridpath)
4. Nortex Feeders, Dalhart, TX (McElroy)