Performance studies of an enzyme-linked immunosorbent assay for detecting Staphylococcus aureus antibody in bovine milk.
An enzyme-linked immunosorbent assay (ELISA) for detecting Staphylococcus aureus antibody in bovine milk samples was examined for repeatability. A set of 51 bovine milk samples from 4 universities with confirmed culture results was assembled, and a panel of 30 milk samples was randomly selected. When the selected panel was tested at the collection laboratory, there was 97% agreement between the ELISA and the culture test. The panel was tested with the ELISA by the 4 university laboratories. Results were scored by both visual and optical density reader methods. When compared to reference ELISA results, the university laboratory ELISA results showed an agreement of 99.8% for negative samples, 98% for positive samples, and 99% for all samples. Additional studies on 19 milk samples that cultured positive for bacteria other than S. aureus showed 100% specificity. Overall comparison of ELISA and culture results showed high agreement between the 2 techniques. Disagreement appeared to result from explainable differences in antibody and bacterial levels and not from errors in either of the 2 techniques.
Matsushita
T
T
ProScience Corp., Sterling, VA 22170.
Dinsmore
R P
RP
Eberhart
R J
RJ
Jones
G M
GM
McDonald
J S
JS
Sears
P M
PM
Adams
D S
DS
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis*; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D008414:Mastitis, Bovine / Q000175:diagnosis*; D008892:Milk / Q000276:immunology*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000662:veterinary*; D013211:Staphylococcus aureus / Q000276:immunology*
D000907:Antibodies, Bacterial