1. Albano Small Animal Hospital; Rinkebyvägen 23 182 36 Danderyd Sweden
2. National Veterinary Institute; Ulls väg 2B 751 89 Uppsala Sweden
3. Department of Pathology; University of Veterinary Medicine; Buenteweg 17 30559 Hannover Germany
4. Department of Clinical Sciences; Swedish University of Agricultural Sciences; Box 7054 750 07 Uppsala Sweden