Author's Organization:School of Veterinary Medicine, Rakuno Gakuen University Department of Epizootiology, Faculty of Veterinary Medicine, Hokkaido University School of Veterinary Medicine, Rakuno Gakuen University School of Veterinary Medicine, Rakuno Gakuen University School of Veterinary Medicine, Rakuno Gakuen University School of Veterinary Medicine, Rakuno Gakuen University
Published: December 15, 1990Received: May 15, 1990Available on J-STAGE: February 14, 2008Accepted: July 18, 1990
Advance online publication: -
Revised: -