1. College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, 4458 TAMU, College Station, Texas 77843, USA;
2. Texas A&M Veterinary Medical Diagnostic Laboratory, PO Drawer 3040, College Station, Texas 77841-3040, USA;
3. USDA-APHIS-Wildlife Services, PO Box 690170, San Antonio, Texas 78269-0170, USA;