1. Key Laboratory of Pig Molecular Quantitative Genetics of Anhui Academy of Agricultural Sciences, Anhui Provincial Key Laboratory of Livestock and Poultry Product Safety Engineering, Institute of Animal Husbandry and Veterinary Medicine, Anhui Academy of Agricultural Sciences, Hefei 230031, China
2. Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650500, China
3. National Animal Husbandry Service, Beijing 100125, China