1. Animal Health Diagnostic Center, Department of Population Medicine and Diagnostic Sciences, Cornell University, 240 Farrier Rd., Ithaca, NY 14853, USA
2. Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
3. College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
4. Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA