Institution: | *Centre for Small Animal Studies, Animal Health Trust, P.O. Box 5, Newmarket, Suffolk CB8 7DW, U.K.;?Centre for Preventive Medicine, Animal Health Trust, P.O. Box 5, Newmarket, Suffolk CB8 7DW, U.K.;§Department of Pathology and Microbiology, Comparative Pathology Laboratory, School of Veterinary Science, Langford, Bristol BS18 7DU, U.K. |