Submitted to: International Workshop on Tuberculosis in Animals
Publication Type: Abstract Only
Publication Acceptance Date: 9/15/1999
Publication Date: N/A
Technical Abstract: The specimen processing method based on the use of Zephiran was compared with the C18-carboxypropylbetaine (CB-18) method (JCM 36:3558-3566, 1998) in an attempt to develop an improved antemortem swab test for detecting Mycobacterium bovis infections in livestock. An initial in vitro comparison simply diluted swab samples that had been spiked with bacilli 1:1 with either 2 mM CB-18 or 0.2% Zephiran. Samples were then subjected to centrifugation and analyzed by culture. In this simple assay, CB-18 processing increased recovery of M. bovis 1315, which was originally isolated from a white-tailed deer, by three- to four-fold when analyzed by quantitative culture. However, after having been processed with CB-18, M. bovis 1315 was unable to grow in BACTEC 12B cultures that had been supplemented with PANTA. Further analysis of the components of PANTA indicated that nalidixic acid at 2.5-20 ug/ml in combination with CB-18 at 10-15 ug/ml was capable of killing this isolate. Modification of the CB-18 processing protocol was required to enable recovery of the M. bovis 1315 isolate. These modifications included first incubating the specimen in 2 mM CB-18 (final) and then diluting CB-18 to approximately 0.2 mM prior to centrifugation.