1. Department of Veterinary Clinical Sciences (Mordecai), College of Veterinary Medicine, Washington State University, P.O. Box 646610, Pullman, Washington 99164-6610; the
2. Departments of Clinical Studies (Liptak, Kruth) and Pathobiology (Stalker), Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada N1G 2W1
3. Woodstock Veterinary Hospital (Hofstede), 866 Nellis, Woodstock, Ontario, Canada N4S 4C4
4. From the