1. Louisiana Veterinary Medical Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana 70803, USA
2. Present address: Department of Pathology, College of Veterinary Medicine, The University of Georgia, Athens, Georgia 30602, USA
3. Present address: Louisiana Reference Laboratories, 6746 Goya Ave., Baton Rouge, Louisiana 70806, USA
4. 8778 Goodwood Boulevard, Baton Rouge, Louisiana 70806, USA
5. Present address: Diagnostic Laboratory Services, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, USA