1. Institute of Veterinary Bacteriology, Bern, University of Bern
2. Graduate School of Cellular and Biomedical Sciences, Bern, University of Bern
3. Department of Clinical Veterinary Medicine, Bern, University of Bern
4. Institute for Infectious Diseases, University of Bern, Bern, Switzerland
5. Clinic for Small Animal Internal Medicine, University of Zurich, Zurich, Switzerland