1. Graduate School of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan
2. Present: Division of Inflammation Research, Center for Molecular Medicine, Jichi Medical University, Tochigi 329-0498, Japan
3. Clinic for Cattle, University of Veterinary Medicine Hannover, Hannover 30173, Germany
4. Present: Clinic for Reproductive Medicine, University of Zürich, Zürich 8006, Switzerland