1. Nutrition and Public Health Intervention Research Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
2. Leverhulme Centre for Intergrative Research in Agriculture and Health London International Development Centre, 36 Gordon Square, London WC1H 0PD, UK
3. School of Oriental and African Studies, University of London, Thornhaugh Street, Russell Square, London, WC1H 0XG London, UK
4. Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
5. London International Development Centre, 36 Gordon Square, London WC1H 0PD, UK