1. Department of Pathobiology and Population Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herfordshire AL9 7TA, UK
2. Institute of Veterinary Bacteriology, University of Bern, Laenggassstrasse 122, 3012 Bern, Switzerland
3. Tierarztpraxis an der Simme, Simmentalstrasse 28, 3752 Wimmis, Switzerland
4. Institute of Parasitology, University of Bern, Laenggassstrasse 122, 3012 Bern, Switzerland
5. Bacteriology and Mycology Unit, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway