This report was prepared for FAO by Dr Ashley Robinson, Associate Dean (Pre-Clinical Program), College of Veterinary Medicine, Western University of Health Sciences, Pomona, California 91766-1854, USA.

With inputs from:

Dr A. Benkirane, Département de Microbiologie, Immunologie et Maladies Contagieuses, Institut Agronomique et Vétérinaire Hassan II, B.P. 6202-Instituts, 10101 Rabat, Morocco.

Dr J.M. Blasco, Unidad de Sanidad Animal, SIA/DGA, Zaragoza, Spain.

Dr M.R. Dalrymple, National Animal Health Programmes, USDA - APHIS, Riverdale, Maryland, USA.

Dr M. Van-Ham, Department of Epidemiology, Veterinary Services and Animal Health, Ministry of Agriculture and Rural Development, PO Box 12, Bet Dagan, 50250 Israel.

Dr A.P. MacMillan, FAO/WHO Collaborating Centre for Reference and Research on Brucellosis, Central Veterinary Laboratory, Weybridge, England, UK.

Dr J.G. Murray, Chief Veterinary Officer, Department of Primary Industries and Energy, Canberra, Australia.

Dr Valerie Ragan, National Animal Health Programmes, USDA - APHIS, Riverdale, Maryland, USA.

Dr Stuart C. MacDiarmid, National Manager (Agricultural Security - Regulatory Authority), Ministry of Agriculture and Forestry, PO Box 2526, Wellington, New Zealand.

Dr Mo. Salman, Department of Microbiology and Environmental Health, College of Veterinary Medicine, Colorado State University, Fort Collins, Colorado, USA.

The inputs are gratefully acknowledged.

This publication was reviewed by Ahmed El Idrissi of the FAO Animal Production and Health Division and staff of the Infectious Diseases Group of the FAO Animal Health Service.

Editorial and technical production coordination was by W. Amanfu and J. Lubroth.

Final preparation for publishing was by Thorgeir Lawrence.