Microtitration agglutination for detection of Treponema hyodysenteriae antibody

A microtitration agglutination test for the detection of Treponema hyodysenteriae antibody in swine and rabbit sera is described. The following methods provided the best test results: antigen produced from the spirochete after a culturing period of 36 to 44 h at 38 degrees C, washed antigen inactivated with 0.01% Merthiolate at 4 degrees C for 24 to 36 h, sera heated at 56 degrees C for 30 min, a diluent of phosphate-buffered saline (0.01 M, pH 7.2), and test results read macroscopically after 18 to 24 h of incubation at 38 degrees C. The test enabled detection of antibody against pathogenic T. hyodysenteriae with a high level of consistency and sensitivity. Sera against nonpathogenic T. hyodysenteriae produced low agglutinating titers (less than or equal to 1:8) when reacted against antigen from pathogenic isolates. Inactivated antigen remained stable for 7 to 10 days. Specificity of the reaction in the agglutination test was shown by absorption studies.