title: Vertical transmission of bovine leukemia virus and bovine immunodeficiency virus in dairy cattle herds.
abstract: Vertical transmission of bovine leukemia virus (BLV) and bovine immunodeficiency virus (BIV) was investigated in five dairy cattle herds in Hokkaido, where 36.1 and 17.0% of cattle were BLV and BIV seropositive, respectively, and 9.9% of dams were co-infected with both BIV and BLV. Twenty six cases of offspring born from dams infected with only BLV (17 cases) or with both BIV and BLV (9 cases) were examined for the presence of BLV and BIV before and after colostrum feeding by polymerase chain reaction (PCR) and syncytium assay. After birth, all calves were separated immediately from their dams. The offspring born from BLV-positive dams were BLV-negative before colostrum feeding, suggesting that no transplacental transmission had occurred. Thereafter, these offspring were fed colostrum or milk from their dams, but still remained BLV-negative. The other offspring born from BLV-positive dams were fed with BLV-negative colostrum, or with pasteurized BLV-positive colostrum. All these calves remained negative for BLV infection, suggesting that in utero transmission of BLV is negligible. In the case of offspring born from dams co-infected with BLV and BIV, calves were BIV-positive before colostrum feeding at 1 day after the birth, indicating in utero transmission of BIV. After colostrum feeding from their dams, newborn calves became BLV-positive. In addition, one calf was BLV-positive even before colostrum feeding. These results suggest that BIV can be transmitted to offspring in utero, and that BLV can be transmitted through colostrum or milk if dams are infected with both BIV and BLV.
authors.affiliation: Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, 060-0818, Sapporo, Japan.
authors.forename: Sothy
authors.initials: S
authors.lastname: Meas
authors.forename: Tatsufumi
authors.initials: T
authors.lastname: Usui
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ohashi
authors.forename: Chihiro
authors.initials: C
authors.lastname: Sugimoto
authors.forename: Misao
authors.initials: M
authors.lastname: Onuma
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000635:transmission*; D003126:Colostrum / Q000821:virology; D016583:Enzootic Bovine Leukosis / Q000453:epidemiology / Q000635:transmission*; D005260:Female; D016087:Immunodeficiency Virus, Bovine / Q000276:immunology; D018445:Infectious Disease Transmission, Vertical / Q000662:veterinary*; D007564:Japan / Q000453:epidemiology; D016180:Lentivirus Infections / Q000453:epidemiology / Q000635:transmission / Q000662:veterinary*; D001909:Leukemia Virus, Bovine / Q000276:immunology; D008892:Milk / Q000821:virology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral