|Vander Ley, Brian|
Submitted to: Journal of Veterinary Laboratory Diagnostics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/13/2012
Publication Date: 5/1/2012
Citation: Vander Ley, B.L., Ridpath, J.F., Sweiger, S.H. 2012. Bovine viral diarrhea virus antigen detection across whole cattle hides using two antigen-capture enzyme-linked immunosorbent assays. Journal of Veterinary Laboratory Diagnostics. 24(3):546-548. Interpretive Summary: Bovine viral diarrhea virus (BVDV) causes several significant diseases of cattle, including abortions and decreased immune function. The majority of BVDV infections can be traced to cattle that have life long BVDV infections. These animals are called persistently infected or PI with the virus. Identifying and removing PI cattle from herds is important for preventing BVDV infections and is accomplished using a variety of diagnostic tests. Developing and ensuring the accuracy of these tests requires large amounts of sample material from animals that are PI and animals that are not PI. A common sample used for testing is skin from the ear. The purpose of this experiment was to determine if the entire skin of cattle is suitable for use in development and accuracy testing of a specific type of diagnostic test called an enzyme linked immunosorbent assays (ELISA). Two different ELISAs were used to test samples taken from the skin of 3 PI calves. One test positively identified every skin sample taken from all 3 animals. The second test identified approximately 60% of all samples as positive. This research demonstrates that some diagnostic tests can utilize any skin sample, whereas others require skin samples from specific areas. This difference in detection requires testing of each diagnostic test to determine what types of samples are appropriate.
Technical Abstract: Bovine viral diarrhea virus is a costly disease of cattle that can be controlled by vaccination, biosecurity, and removal of persistently infected cattle. Development and proficiency testing of assays to identify persistently infected cattle substantial quantities of known positive and negative sample material. The objective of this study was to determine what sections of bovine skin contained bovine viral diarrhea virus antigen. Two commercially available antigen capture enzyme linked immunoassays were used to test subsamples representing the entire skin of 3 persistently infected calves. Both assays detected bovine viral diarrhea virus antigen in the samples indicated for use by assay protocol. However, one assay identified all subsamples as positive while the second assay identified 64.4% of subsamples as positive. Further analysis of data from the second assay showed that significant differences in detected antigen were present between different sections of skin. These results show that use of samples other than those specified by the assay protocol must be validated for each individual assay. In this study alternative sample sites and use of the entire hide for proficiency testing would be acceptable for only one of the assays tested.