1. College of Animal Science and Veterinary MedicineShandong Agricultural University Tai'an China
2. College of AgricultureLiaocheng University Liaocheng China
3. Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal ScienceChinese Academy of Agricultural Sciences Beijing China
4. Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal ScienceChinese Academy of Agricultural Sciences Beijing China