1 The Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK.
2 WildGenes Laboratory, Royal Zoological Society of Scotland, Edinburgh EH12 6TS, UK.
3 Small Animal Hospital, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
4 Powell Torrance Diagnostic Services, Manor Farm Business Park, Higham Gobion, Hertfordshire SG5 3HR, UK.
5 Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, Republic of South Africa.