1. Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB R3E 3R2, Canada
2. National Veterinary Laboratory, Instituto Colombiano Agropecurio, Bogota 110911, DC, Colombia
3. Department of Animal Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
4. Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada