1. Giardino Zoologico di Pistoia, Via Pieve a Celle 160a, 51100 Pistoia, Italy
2. Centre for Animal Welfare, Faculty of Health and Wellbeing, University of Winchester, Sparkford Road, Winchester SO22 4NR, UK
3. School of Environment and Science, Nathan Campus, Griffith University, 170 Kessels Rd, Nathan, Brisbane, QLD 4111, Australia