title: Comparison of fluorescent antibody and microscopic agglutination testing for Leptospira in pregnant and nonpregnant cows.
abstract: Serum and urine samples from 30 cows (15 pregnant and 15 nonpregnant) from each of 10 Georgia dairy herds (total cows = 300) were examined by microscopic agglutination testing (MAT) and direct fluorescent antibody testing (FAT), respectively. Seven of the 10 herds had at least 1 cow with a positive FAT, and all of the herds had at least 1 cow with a reciprocal MAT titer > or =100 for 1 or more serovars. Serological testing was not helpful in identifying the infecting serovar for cows with a positive FAT result. The MAT titers for all 7 of the serovars evaluated were significantly correlated with one another, with 17 (81%) of the 21 Spearman rank correlation coefficients > or =0.4 in magnitude. Twenty (56%) of 36 FAT-positive cows did not have a titer that was highest for any particular serovar. Four of the 7 herds that reported using a Leptospira borgpetersenii serovar Hardjo-bovis vaccine had one or more FAT-positive cows compared with 3 out of 3 herds that reported they were not using this type of vaccine, although this difference was not statistically significant.
authors.affiliation: The University of Georgia, The College of Veterinary Medicine, Veterinary Diagnostic and Investigational Laboratory, 43 Brighton Road, Tifton, GA 31794, USA. srajeev@uga.edu
authors.forename: Sreekumari
authors.initials: S
authors.lastname: Rajeev
authors.forename: Roy D
authors.initials: RD
authors.lastname: Berghaus
authors.forename: Michael W
authors.initials: MW
authors.lastname: Overton
authors.forename: Mel E
authors.initials: ME
authors.lastname: Pence
authors.forename: Charles A
authors.initials: CA
authors.lastname: Baldwin
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary*; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000652:urine; D005260:Female; D005455:Fluorescent Antibody Technique / Q000662:veterinary*; D007919:Leptospira / Q000302:isolation & purification*; D007922:Leptospirosis / Q000175:diagnosis / Q000652:urine / Q000662:veterinary*; D008853:Microscopy; D011247:Pregnancy