1. Division of Genetics and Genomics, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom.
2. Department of Ecology and Vertebrate Zoology, University of Łódź, 90-237 Łódź, Poland.
3. Centre for Tropical Livestock Genetics and Health (CTLGH), ILRI Kenya, P.O. Box 30709, Nairobi, Kenya.