1. Department of Anatomy and Physiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
2. Department of Clinical Sciences, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
3. Department of Animal Science, Kansas State University, Manhattan, KS, USA
4. Department of Diagnostic Medicine/Pathobiology and Kansas State Veterinary Diagnostic Laboratory, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
5. Merck Animal Health, De Soto, KS, USA