title: Comparative serological study of Leptospira serovar hardjo genotypes for use in the microscopic agglutination test.
abstract: A comparative serological study was conducted using the Leptospira microscopic agglutination test (MAT). Genotypes hardjoprajitno (HP), hardjo-bovis A (HA), and hardjo-bovis B (HB) were compared to determine which best detects hardjo antibody in cattle serum. A total of 2,431 cattle sera were tested. Sera were collected from 4 geographic regions of the United States. Samples were obtained without knowledge of breed, age, vaccination history, or herd health status. Of the sera collected, 60.7% (1,475) were negative at the 1 : 100 dilution for all three genotypes. Serological reactivity at the 1 : 100 dilution was identified in 956 (39.3%) of the sera tested. Considering the 956 positive sera, 941 (98.4%) reacted to HP, whereas the remaining 15 sera (1.6%) reacted to only HA and/or HB. A total of 394/941 (41.9%) HP positive sera failed to react to HA or HB. The results of this study support the conclusion that HP antigen was most sensitive in detection of hardjo antibody.
authors: USDA, 1800 Dayton Avenue, Ames, IA 50010, USA. Morgan.L.Hotka@aphis.usda.gov
authors: Morgan L
authors: ML
authors: Hotka
authors: Mark A
authors: MA
authors: Wilson
authors: Tammy M
authors: TM
authors: Anderson
authors: Corrie L
authors: CL
authors: Tichenor
authors: David A
authors: DA
authors: Miller
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary*; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000175:diagnosis; D005838:Genotype; D007919:Leptospira / Q000145:classification / Q000235:genetics*; D007922:Leptospirosis / Q000097:blood / Q000175:diagnosis; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000662:veterinary*