Institution: | 1. EpiCentre, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11222, Palmerston North, New Zealand E-mail: n.r.perkins@massey.ac.nz;2. Veterinary Informatics and Epidemiology, Department of Veterinary Clinical Studies , University of Glasgow Veterinary School , Glasgow G61 1QH, Bearsden, Scotland |