Affiliation: | 1.Nihon University Veterinary Research Center,Nihon University,Fujisawa,Japan;2.Department of Veterinary Science,National Institute of Infectious Diseases,Tokyo,Japan;3.Department of Veterinary Medicine, Center of Health and Rural Technology,Federal University of Campina Grande,Patos,Brazil;4.Faculty of Veterinary Medicine and Zootechny,University of S?o Paulo,S?o Paulo,Brazil |