1. SAC Veterinary Services, Inverness IV2 4JZ, UK
2. Department of Clinical Microbiology, Karolinska University Hospital, MTC, Stockholm SE-17176, Sweden
3. Faculty of Veterinary Science, Department of Veterinary Tropical Diseases, University of Pretoria, Onderstepoort 0110, South Africa
4. Institut Universitaire de Technologie, Université François Rabelais, 29 rue du Pont-Volant, 37082 Tours cedex 2, France
5. INRA, UR1282, Infectiologie Animale et Santé Publique, IASP, Nouzilly, F-37380, France