1. Institute of Animal Pathology; Vetsuisse Faculty; University of Bern; Länggassstrasse 122 3001 Bern Switzerland
2. Division of Internal Medicine; Department of Clinical Veterinary Medicine; Vetsuisse Faculty; University of Bern; Länggassstrasse 124 3001 Bern Switzerland
3. Institute of Pathology; Division of Immunopathology; University of Bern; Murtenstrasse 31 3010 Bern Switzerland