1. Weipers Centre for Equine Welfare; Institute of Comparative Medicine; Faculty of Veterinary Medicine; University of Glasgow; Bearsden Road Glasgow G61 1QH
2. Boyd Orr Centre for Population and Ecosystem Health; Institute of Comparative Medicine; Faculty of Veterinary Medicine; University of Glasgow; Bearsden Road Glasgow G61 1QH
3. School of Animal and Veterinary Sciences; Charles Stuart University; Locked Bag 588 Wagga Wagga New South Wales 2678 Australia