1. Shandong Jihua Poultry Breeding Co. Ltd, Rizhao, China
2. Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
3. College of Animal Science and Technology, China Agricultural University, Beijing, China
4. Deparment of Animal Gerplasm Resources, Shandong General Station of Animal Husbandry, Jinan, China