COMPARISON OF MICROBIOLOGIC CULTURE, AN ENZYME-LINKED-IMMUNOSORBENT-ASSAY, AND DETERMINATION OF SOMATIC-CELL COUNT FOR DIAGNOSING STAPHYLOCOCCUS-AUREUS MASTITIS IN DAIRY-COWS
Cr. Hicks et al., COMPARISON OF MICROBIOLOGIC CULTURE, AN ENZYME-LINKED-IMMUNOSORBENT-ASSAY, AND DETERMINATION OF SOMATIC-CELL COUNT FOR DIAGNOSING STAPHYLOCOCCUS-AUREUS MASTITIS IN DAIRY-COWS, Journal of the American Veterinary Medical Association, 204(2), 1994, pp. 255-260
Results of using microbiologic culture of a single milk sample, determ
ination of somatic cell count (SCC), an ELISA, and a combination of de
termination of SCC and ELISA to diagnose Staphylococcus aureus mastiti
s in dairy cattle were compared. Cows were considered to have S aureus
intramammary infections if microbiologic culture of at least 2 of 3 c
onsecutive sets of milk samples yielded growth of the organism. Data w
ere analyzed from milk samples collected over a 4-month period from 18
5 cows in 5 herds. Sensitivity, specificity, and likelihood ratio of a
positive test result for microbiologic culture of a single milk sampl
e weve 93%, 99%, and 93.0, respectively. Sensitivity, specificity, and
likelihood ratio of a positive test result for ELISA were 69%, 61%, a
nd 1.8, respectively, and for determination of sec, they weve 79%, 72%
, and 2.9, respectively. Combination of determination of SCC and ELISA
had sensitivity, specificity, and likelihood ratio of a positive test
result of 80%, 62%, and 3.4, respectively. Results from microbiologic
culture of consecutive milk samples were more consistent than results
of ELISA performed on consecutive samples. These data suggest that mi
crobiologic culture of a single milk sample is the best of the 3 tests
studied for diagnosing S aureus intramammary infection.