Features of sheep border disease

Abstract

Border sheep disease - viral congenital disease of sheep and goats that occurs during infection of pregnant ewes, characterized by lesions of the reproductive organs (abortions, stillbirths, infertility, birth of nonviable, mummified, undeveloped and ugly lambs) and organs of the immune system, growth retardation of newborn lambs, pathology of myelogenesis. The name of the disease was determined by the place of registration of the disease in 1959, in the border zone between England and Wales. Sheep border disease is considered to be one of the most common infections, causing great economic damage to cattle breeding worldwide. Infection of susceptible animals can proceed after the use of Pestivirus contaminated modified live virus vaccines. Border disease causative agent spreads with persistently infected animals. Border disease virus transmission can occur in mixed grazing of large horned cattle with infected sheep and goats and vice versa. Border disease virus was also isolated from deer, roe deer and other wild ruminants. 70-80% of lymphocytes in experimentally infected sheep contain the virus. Immunodeficiency state is detected in ruminants infected with border disease. The survival rate of offspring ranged from 59% to 88% during experimental infection with the border disease virus of pregnant ewes. The causative agent of border disease has negligible pathogenicity for pigs, but is highly pathogenic for large horned cattle, and cause potentially serious disorders of reproduction.