1. California Veterinary Diagnostic Laboratory System, Turlock Branch, School of Veterinary Medicine, University of California-Davis, PO Box 1522, Turlock, CA 95381
2. California Veterinary Diagnostic Laboratory System, School of Veterinary Medicine, University of California, Davis, CA 95616
3. Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616