1. College of Veterinary Medicine, North-west A&F University, Yangling 712100, China.
2. Chinese Institute of Veterinary Drug Controls, Beijing 100000, China.
3. VIDO-InteVac, School of Public Health, University of Saskatchewan Saskatoon, Saskatchewan S4S 6A6, Canada.
4. Vaccinology & Immunotherapeutics Program, School of Public Health, University of Saskatchewan Saskatoon, Saskatchewan S4S 6A6, Canada.