1. Department of Biology and Microbiology, South Dakota State University, Brookings, SD, USA
2. Animal Disease Research and Diagnostic Laboratory, South Dakota State University, Brookings, SD, USA
3. Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD, USA
4. Kansas State Veterinary Diagnostic Laboratory and Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, USA
5. Department of Veterinary Science, University of Kentucky, Lexington, KY, USA