1. Department of Veterinary Diagnostic and Production Animal Medicine College of Veterinary Medicine Iowa State University Ames IA USA
2. Key Laboratory of Livestock Disease Prevention of Guangdong Province Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province Institute of Animal Health Guangdong Academy of Agricultural Sciences Guangzhou China
3. Department of Veterinary Clinical Medicine and the Veterinary Diagnostic Laboratory College of Veterinary Medicine University of Illinois Urbana IL USA
4. Arkcare Fairbury NE USA