title: Bovine leukemia virus seroprevalence among cattle presented for slaughter in the United States.
abstract: Infection with bovine leukemia virus (BLV) results in economic loss because of reduced productivity, especially reduced milk production, and early culling. In the United States, studies in 1996, 1999, and 2007 showed BLV infection to be widespread, especially in dairy herds. We updated information herein on BLV seroprevalence in the United States, using samples submitted for testing and found negative for antibodies for Brucella by the Kentucky Eastern Regional Federal Brucellosis Laboratory. From October 2014 through August 2015, 2,000 samples from all regions of the contiguous United States were selected and tested for BLV antibodies by enzyme-linked immunosorbent assay. The overall percentage of samples positive for BLV antibody was 38.6%. Based on the animal's origin, the percent positive by region ranged from 32.5% (Mountain West region) to 54.3% (Northeast region; p < 0.05). The positive rate for slaughter plants that processed mainly dairy animals (dairy plants; 47.6%) was higher than the positive rate at slaughter plants that processed mainly beef animals (beef plants; 33.6%; p < 0.05). The results suggest that BLV infection remains widespread in all regions of the United States and that rates may differ between beef and dairy cattle.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Ames, IA (Bauermann, Ridpath).|U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Center for Epidemiology and Animal Health, Fort Collins, CO (Dargatz).
authors.forename: Fernando V
authors.initials: FV
authors.lastname: Bauermann
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Ames, IA (Bauermann, Ridpath).|U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Center for Epidemiology and Animal Health, Fort Collins, CO (Dargatz).
authors.forename: Julia F
authors.initials: JF
authors.lastname: Ridpath
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Ames, IA (Bauermann, Ridpath).|U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Center for Epidemiology and Animal Health, Fort Collins, CO (Dargatz).
authors.forename: David A
authors.initials: DA
authors.lastname: Dargatz
mesh_terms: D000003:Abattoirs; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002417:Cattle; D003430:Cross-Sectional Studies; D016583:Enzootic Bovine Leukosis / Q000453:epidemiology* / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D001909:Leukemia Virus, Bovine / Q000302:isolation & purification*; D015995:Prevalence; D016036:Seroepidemiologic Studies; D014481:United States / Q000453:epidemiology
chemical_list: D000914:Antibodies, Viral
keywords: Antibodies; Bovine leukemia virus; enzyme-linked immunosorbent assay; prevalence; retrovirus