1. Animal Genomics and Improvement Laboratory, BARC, Agricultural Research Service, USDA, Beltsville, MD, USA
2. Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
3. Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, Hubei, China
4. Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
5. Dairy Forage Research Center, Agricultural Research Service, USDA, Madison, WI, USA