1. Enzyme R & D, Genencor, Danisco A/S, DK 8220 Brabrand, Aarhus, Denmark
2. Department of Biotechnology, Lund University, Lund, Sweden
3. Poultry Research Foundation, Veterinary Science Faculty, University of Sydney, Camden, NSW 2570, Australia
4. Danisco Animal Nutrition, SN8 1AA Marlborough, United Kingdom