1. Department of Veterinary Clinical Sciences; College of Veterinary Medicine; Iowa State University; 1800 Christensen Drive Ames IA 5011 USA
2. Department of Small Animal Clinical Sciences; UT College of Veterinary Medicine; University of Tennessee; 2407 River Drive Knoxville TN 37996 USA
3. Department of Biomedical and Diagnostic Sciences; UT College of Veterinary Medicine; University of Tennessee; 2407 River Drive Knoxville TN 37996 USA