1. State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China
2. Academy of National Food and Strategic Reserves Administration, Beijing, China
3. Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, College of Veterinary Medicine, China Agricultural University, Beijing, China
4. Department of Animal Science, Division of Agriculture, University of Arkansas, Fayetteville, AR, USA