1. Department of Clinical Studies, Ontario Veterinary College University of Guelph Guelph Ontario Canada
2. Department of Clinical Studies, College of Veterinary Medicine University of Florida Gainesville Florida USA
3. Département de Sciences Cliniques, Faculté de Médecine Vétérinaire Université de Montréal Montréal Quebec Canada
4. Department of Comparative, Diagnostic & Population Medicine, College of Veterinary Medicine University of Florida Gainesville Florida USA