Bovine anaplasmosis (BA) is a hemoparasitic disease of great importance in cattle within the tropical and subtropical regions of the world. Control programs for BA require accurate diagnostic assays but validation can be challenging because the true disease status of all animals is frequently not known with certainty. The objective of this study was to estimate the accuracy of assays for detect...

The major group-specific antigen (gs-a) of avian leukoviruses was detected by radioimmunoassay in extracellular medium of all embryonic cultures prepared from infected chickens. Embryos of birds not carrying an avian ]eukosis virus infection and of chickens from a leukosis-free flock could thus clearly be distinguished from infected ones. Release of group-specific antigen into the extracellular...

Avian lymphoid leukosis can be induced by lymphoid leukosis viruses belonging to Subgroups A, B, C, and D. The endogenous virus of the chicken (Rous-associated virus type 0) belongs to Subgroup E and has little, if any, potential for inducing lymphoid leukosis. Nearly all chicken flocks are infected with Subgroup A lymphoid leukosis virus. This virus can be transmitted from dam to offspring or ...

We report herein on the first evidence for the presence of bovine immunodeficiency virus (BIV) in Zambia. Serological surveillance of BIV and bovine leukemia virus (BLV) was conducted in traditional cattle herds in Zambia. Out of a total of 262 sera analyzed, 11.4% were found positive for anti-BIV p26 antibodies as determined by Western blot analysis, while 5.0% were positive for anti-BLV gp51 ...

It is of critical importance to understand the modalities of BLV presence in semen, especially with regard to artificial insemination (AI). Presence of bovine leukemia provirus was demonstrated in fresh and frozen semen samples by researchers. In this study paired blood and semen samples from 45 bulls were assessed for the presence of part of gag gene and antibodies to BLV in blood, semen and c...

Thirteen monoclonal antibodies directed against tumor cells from cattle from enzootic bovine leukosis (EBL) were obtained. They reacted with tumor cells but not with normal bovine cells or bovine leukemia virus antigens. According to the reactivities of these antibodies with 19 individual tumors, the 13 monoclonal antibodies can be divided into three groups. Antibodies of the first group reacte...

Bovine leukemia virus (BLV) is the etiologic agent of enzootic bovine leukosis. We previously identified several mutants of the BLV Tax protein with an ability to transactivate transcription via the BLV enhancer that is significantly greater than that of the wild-type Tax protein. Moreover, the mutant proteins also activated other viral enhancers, such as the enhancer of human T-cell leukemia v...

In human immunodeficiency virus (HIV)-infected individuals, the proportion of circulating mononuclear cells (PBMCs) which carry HIV provirus and the number of HIV proviral sequences per infected PBMC have been matters for conjecture. Using a double polymerase chain reaction which allows the detection of single molecules of provirus and a method of quantifying the provirus molecules, we have mea...