1. Department of Animal & Avian Sciences, University of Maryland, College Park, Maryland 20742
2. United States Department of Agriculture-Agriculture Research Service (ARS), Avian Disease and Oncology Laboratory, East Lansing, Michigan 48823
3. Bovine Functional Genomic Laboratory, Animal and Natural Resources Institute, United States Department of Agriculture-Agricultural Research Service, Beltsville, Maryland 20705
4. Department of Animal Breeding and Genetics, College of Animal Sciences, China Agricultural University, Beijing, 100193, People's Republic of China