College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.School of Engineering and Information Technology, Mathematics & Statistics, Murdoch University, Murdoch, Western Australia, Australia.Centre for Applied Statistics (M019), University of Western Australia, Nedlands, Western Australia, Australia.Centre for Applied Statistics (M019), University of Western Australia, Nedlands, Western Australia, Australia.College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.