1 Institute of Animal Husbandry and Veterinary Medicine (IAHVM), Beijing Academy of Agriculture and Forestry Sciences (BAAFS), Beijing, China.
2 Joint Laboratory of Animal Science Between IAHVM of BAAFS and Division of Agricultural Science and Natural Resource of Oklahoma State University, Beijing, China.
3 College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China.
4 College of Animal Science and Technology, Hebei North University, Zhangjiakou, China.
5 Department of Infectious Diseases and Public Health, City University of Hong Kong, Hong Kong, China.