1. Institute for Virology, Faculty of Veterinary Medicine, University of Leipzig , An den Tierkliniken 29, D-04103, Leipzig, Germany
2. Institute for Avian Diseases, Ludwig-Maximilians-University Munich , Sonnenstraße 18, D-85764, Oberschleißheim, Germany
3. Clinic for Birds, Reptilia, Amphibia and Fish, Justus Liebig University Giessen , Frankfurter Straße 91-93, D-35392, Giessen, Germany