In this research, the pathogenesis and presence of transplacental pestivirus infection were investigated in different flocks. For this purpose, a total of 661 pregnant ewes and 29 rams were used. 174 of 661 pregnant ewes were sampled twice in the second or the third month of gestation and as well as on the day of gestation, whereas 487 of them were sampled only on the day of delivery. In addition, precolostral blood samples of 770 lambs born from those pregnant ewes, 109 of which delivered twins, were also withdrawn. Pestivirus was not detected in the blood samples tested. However, in some precolostral blood samples from lambs, pestivirus specific antibodies were detected indicating transplacental transmission of the virus during late pregnancy.