Hardin L E, Thorne J G
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia 65211, USA.
J Am Vet Med Assoc. 1996 Jul 1;209(1):120-2.
To compare milk with serum ELISA for detection of antibodies to Mycobacterium paratuberculosis.
Epidemiologic survey.
821 Missouri dairy cattle of 12 herds that were brucellosis certified and Dairy Herd Improvement Association members.
Milk and serum samples obtained concurrently from Missouri dairy herds were tested by use of a standard ELISA procedure. Concurrent collection of milk and serum samples controlled for interactions such as colostral antibodies and the effect of time. On the basis of milk and serum ELISA values, disease prevalence and correlation between milk and serum test results were determined.
Correlation measures on individual animals indicated low correlation of milk and serum ELISA values. McNemar's chi 2 of 7.6 was significant (P = 0.05). Analysis correlation was low (kappa = 0.08), as was regression analysis (R2 = 0.02).
Milk ELISA for the detection of exposure to M paratuberculosis lacked correlation with serum ELISA. Further evaluation to determine sensitivity and specificity of milk ELISA will augment the usefulness of milk ELISA as a herd screening test.
