1. Departamento de Zootecnia, Universidade Federal de Viçosa, 36570-000 Viçosa, Brazil
2. Animal Breeding and Genomics Centre, Wageningen University, P.O. Box 338, 6700 AH Wageningen, the Netherlands
3. TOPIGS Research Center IPG, P.O. Box 43, 6640 AA Beuningen, the Netherlands