Estimation of the sensitivity and specificity of the agar gel immunodiffusion test for bovine leukemia virus: 1,296 cases (1982-1989)

• Published in: Journal of the American Veterinary Medical Association Vol. 200; no. 12; p. 2001
• Main Authors: Monke, D R, Rohde, R F, Hueston, W D, Milburn, R J
• Format: Journal Article
• Language: English
• Published: United States 15-06-1992
• Subjects: Animals; Antibodies, Viral - blood; Breeding; Cattle; Enzootic Bovine Leukosis - diagnosis; Evaluation Studies as Topic; False Negative Reactions; False Positive Reactions; Immunodiffusion; Leukemia Virus, Bovine - immunology; Leukemia Virus, Bovine - isolation & purification; Male; Retrospective Studies; Sensitivity and Specificity
• ISSN: 0003-1488
• DOI: 10.2460/javma.1992.200.12.2001

A retrospective study of the results of 12,549 agar gel immunodiffusion tests for bovine leukemia virus, conducted on 1,296 dairy bulls over an 8-year period, was performed to estimate the sensitivity and specificity of the test. The number of tests performed on each bull ranged from 5 to 35, with a mean of 9.7 tests per bull. Bulls were categorized by their agar gel immunodiffusion test responses; 1,069 (82.5%) were noninfected and 227 (17.5%) were infected. Eighteen false-positive results were reported from the noninfected bulls. Test specificity was estimated to be 99.8%. Thirty-one false-negative results were reported from the infected bulls. Test sensitivity was estimated to be 98.5%. Fifty-six bulls had 1 or more positive responses when less than 6 months old. In 26 (46%), these results were thought to be attributable to colostral immunity.