Border Disease: Congenital disorder of lambs caused by a virus closely related to or identical with certain strains of bovine viral diarrhea virus.Border disease virus: A species of PESTIVIRUS causing a congenital sheep disease characterized by an abnormally hairy birth-coat, tremors, and poor growth.Rupicapra: A genus of ruminants in the family Bovidae. The common name chamois usually refers to the species Rupicapra rupicapra. Rupicapra pyrenaica, found in the Pyrenees, is more properly referred to as the Pyrenean chamois.Pestivirus: A genus of FLAVIVIRIDAE, also known as mucosal disease virus group, which is not arthropod-borne. Transmission is by direct and indirect contact, and by transplacental and congenital transmission. Species include BORDER DISEASE VIRUS, bovine viral diarrhea virus (DIARRHEA VIRUS, BOVINE VIRAL), and CLASSICAL SWINE FEVER VIRUS.Diarrhea Viruses, Bovine Viral: A group of viruses in the genus PESTIVIRUS, causing diarrhea, fever, oral ulcerations, hemorrhagic syndrome, and various necrotic lesions among cattle and other domestic animals. The two species (genotypes), BVDV-1 and BVDV-2 , exhibit antigenic and pathological differences. The historical designation, BVDV, consisted of both (then unrecognized) genotypes.Pestivirus Infections: Infections with viruses of the genus PESTIVIRUS, family FLAVIVIRIDAE.Sheep Diseases: Diseases of domestic and mountain sheep of the genus Ovis.Classical swine fever virus: A species of the PESTIVIRUS genus causing exceedingly contagious and fatal hemorrhagic disease of swine.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Bovine Virus Diarrhea-Mucosal Disease: Acute disease of cattle caused by the bovine viral diarrhea viruses (DIARRHEA VIRUSES, BOVINE VIRAL). Often mouth ulcerations are the only sign but fever, diarrhea, drop in milk yield, and loss of appetite are also seen. Severity of clinical disease varies and is strain dependent. Outbreaks are characterized by low morbidity and high mortality.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.