This work discloses the epidemiology, clinical and pathological features of Maedi-visna virus infection in Ethiopian highland sheep. Because of its wide distribution to major sheep producing areas of the country, Maedi-visna found to be one of the major constraints of the sheep industry. The economic importance of the disease rests with losses associated with morbidity, mortality, decreased productivity, and loss of marketing opportunities as a result of restrictions. The emergence and high incidence of the disease particularly in improved breeds of sheep at ranches has critically hampered...