1. USDA, APHIS, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado 80521, USA
2. Current address: USGS, National Wildlife Health Center, 6006 Schroeder Rd, Madison, Wisconsin, 53711 USA
3. Department of Wildlife and Fisheries, Mississippi State University, Starkville, Mississippi 39762, USA
4. USDA, APHIS, Wildlife Services, National Wildlife Research Center, Texas Field Station, Kingsville, Texas 78363, USA
5. USDA, APHIS, Wildlife Services, Moseley, Virginia 23120, USA
6. Caesar Kleberg Wildlife Research Institute, Texas A&M University–Kingsville, Kingsville, Texas 78363, USA
7. Colorado State University, Veterinary Diagnostic Laboratory, Fort Collins, Colorado 80523, USA
8. USDA, APHIS, Wildlife Services, National Wildlife Research Center, Florida Field Station, Gainesville, Florida 32641, USA