1. Colorado State University Veterinary Diagnostic Laboratory, Diagnostic Medicine Center, Colorado State University, Fort Collins, Colorado, USA
2. Department of Microbiology, Pathology and Immunology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
3. Biomedical Sciences Department, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA