1. *Research and Development, Hy-Line International, Dallas Center, IA;
2. †Department of Animal Genetics and Conservation, Institute of Animal Science, Warsaw University of Life Sciences, Warsaw, Poland;
3. ‡Department of Animal Science, Iowa State University, Ames, IA;
4. §Department of Animal and Food Science, University of Delaware, Newark, DE; and
5. ¶Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV