1. Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, Tennessee, USA
2. Present Address: Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 South Lincoln Avenue, Urbana, Illinois, USA
3. Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, Tennessee, USA
4. Virology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
5. Wildlife Center of Virginia, PO Box 1557, Waynesboro, Virginia, USA
6. College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina, USA