Open AccessDetermination of the Mutant Selection Window and Evaluation of the Killing of Mycoplasma gallisepticum by Danofloxacin, Doxycycline, Tilmicosin, Tylvalosin and Valnemulin
Author(s) -
Nan Zhang,
Xiaomei Ye,
Yuzhi Wu,
Zibin Huang,
Xiaoyan Gu,
Quan-Ying Cai,
Xin Shen,
Hongxia Jiang,
Huanzhong Ding
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0169134
Subject(s) - tilmicosin , danofloxacin , mycoplasma gallisepticum , doxycycline , biology , microbiology and biotechnology , selection (genetic algorithm) , virology , mycoplasma , antibiotics , computer science , enrofloxacin , ciprofloxacin , artificial intelligence
Mycoplasma gallisepticum is a common etiological cause of a chronic respiratory disease in chickens; its increasing antimicrobial resistance compromises the use of tetracyclines, macrolides and quinolones in the farm environment. Mutant selection window (MSW) determination was used to investigate the propensity for future resistance induction by danofloxacin, doxycycline, tilmicosin, tylvalosin and valnemulin. Killing of M . gallisepticum strain S6 by these antimicrobials was also studied by incubating M . gallisepticum into medium containing the compounds at the minimal concentration that inhibits colony formation by 99% (MIC 99 ) and the mutant prevention concentration (MPC). Based on the morphology and colony numbers of M . gallisepticum on agar plates, the four kinds of sera in the order of the applicability for culturing M . gallisepticum were swine serum > horse serum > bovine serum > mixed serum. The MPC/MIC 99 values for each agent were as follows: danofloxacin > tilmicosin > tylvalosin > doxycycline > valnemulin. MPC generated more rapid and greater magnitude killing than MIC 99 against M . gallisepticum . Under exposure of 10 5 –10 9 CFU/mL at MPC drug levels, valnemulin had the slowest rate of reduction in viable organisms and danofloxacin had the highest rate of reduction.