1. a EpiCentre, Institute of Veterinary , Animal and Biomedical Sciences, Massey University , Private Bag 11222, Palmerston North, New Zealand
2. c 55A Alderley Street, Toowoomba, Queensland, 4350, Australia E-mail:
3. b Veterinary Informatics and Epidemiology, Department of Veterinary Clinical Studies , University of Glasgow Veterinary School , Glasgow G61 1QH, Bearsden, Scotland