1. Department of Clinical Sciences; University Animal Hospital, Swedish University of Agricultural Science; SE-750 07 Uppsala Sweden
2. Veterinary Information Network; Davis CA 95616 USA
3. Department of Clinical Sciences; School of Veterinary Medicine, University of Perugia; Perugia 06100 Italy
4. Wey Referrals; 25 Chertsey Rd, Woking Surrey GU21 5BP
5. Department of Clinical Sciences; The Koret School of Veterinary Medicine, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem; Rehovot 76100 Israel