1. The Roslin Institute and R(D)SVS, University of Edinburgh, EH25 9RG, United Kingdom.
2. Centre for Tropical Livestock Genetics and Health, Roslin Institute, University of Edinburgh, EH25 9RG, United Kingdom.
3. Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Herts, AL5 2JQ, United Kingdom.
4. Animal and Human Health Programme, 4International Livestock Research Institute, Nairobi, Kenya.
5. Biochemistry & Molecular Biology, Egerton University, Kenya.