1. Animal Health Group, SAC, Edinburgh, United Kingdom;
2. BioSS, Edinburgh, United Kingdom;
3. Departamento de Ciencias Biomédicas, and Instituto de Biomedicina, Universidad de León, León, Spain;
4. Farm Animal Ethology and Poultry Production, University of Hohenheim, Stuttgart, Germany; and
5. Institute of Biology, University of Southern Denmark, Odense, Denmark
6. Sustainable Livestock Systems, Scottish Agricultural College, Odense, Denmark, Edinburgh, United Kingdom;
7. School of Agriculture, Food and Rural Development, Newcastle University, Newcastle upon Tyne, United Kingdom;