1. 1Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
2. 2Institute of Animal Husbandry, Heilongjiang Academy of Agricultural Sciences, Harbin, China
3. 3Department of Animal Science, Heilongjiang State Farms Science Technology Vocational College, Harbin, China
4. 4CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
5. 5Beijing Key Laboratory of Animal Genetic Improvement, China Agricultural University, Beijing, China