Comparison of the antimicrobial activities of gallium nitrate and gallium maltolate against Mycobacterium avium subsp paratuberculosis in vitro

Johne's disease (JD) is an enteric infection of cattle and other ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). This study compared the antimicrobial activities of gallium nitrate (GaN) and gallium maltolate (GaM) against two field MAP isolates by use of broth culture. The concentrations that resulted in 99% growth inhibition of isolates 1 and 2 were, respectively, 636 mu M and 183 mu M for GaN, and 251 mu A and 142 mu M for GaM. For both isolates, time to detection was significantly higher for GaM than GaN. These results suggest that GaM is more efficient than GaN in inhibiting MAP growth in vitro. (C) 2014 Elsevier Ltd. All rights reserved.