1. Department of Pathology; University of Veterinary Medicine Hannover; Bünteweg 17 30559 Hannover Germany
2. Small Animal Clinic; University of Veterinary Medicine Hannover; Bünteweg 9 30559 Hannover Germany
3. State Agency for Agriculture, Environment and Rural Areas, Schleswig-Holstein; Hamburger Chausse 25 24220 Flintbeck Germany