1. Unit of Reproductive Medicine of Clinics - Small Animal Clinic; University of Veterinary Medicine Hannover; Hannover Germany
2. Institute for Pathology; University of Veterinary Medicine Hannover; Hannover Germany
3. Institute for Animal Breeding and Genetics; University of Veterinary Medicine Hannover; Hannover Germany
4. Clinic for Cattle; Laboratory for Endocrinology; University of Veterinary Medicine Hannover; Hannover Germany
5. Faculty of Veterinary Medicine; Institute of Physiological Chemistry; University of Leipzig; Leipzig Germany