1. Louisiana State University, School of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, Louisiana 70803, USA
2. Current address: Centers for Disease Control and Prevention, Foodborne and Diarrheal Diseases Branch, 1600 Clifton Rd., NE MS D-63, Atlanta, Georgia 30333, USA
3. United States Department of Agriculture, Agricultural Research Service, Meat Animal Research Center, PO Box 166, Clay Center, Nebraska 68933, USA
4. Louisiana Department of Wildlife and Fisheries, Deer Study Leader, 2000 Quail Drive, Baton Rouge, Louisiana 70808, USA
5. Current address: University of Montreal, Faculty of Veterinary Medicine, Saint-Hyacinthe, Quebec J2S 7C6, Canada