1. Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, UK
2. Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
3. Metabiota, 1 Sutter Street, Suite 600, San Francisco, CA 94104, USA
4. Liphook Equine Hospital, Forest Mere, Liphook, Hampshire, UK
5. The Donkey Sanctuary, Sidmouth, Devon, UK