This timely publication updates and standardizes currently used diagnostic procedures for this widespread, economically costly livestock disease. It includes state-of-the-art technology, now in limited use, which will replace the conventional methodology in the near future. The volume covers research done on improved diagnostic techniques, vaccines, taxonomy, epidemiology, pathology, and basic immunology. It is an important literature review for those more established in this field and serves as a guide to researchers or diagnosticians becoming involved with this disease.