TABLE 2.
Initial and final MIC50s, MIC90s, and MIC ranges of antimicrobials against Belgian M. hyopneumoniae field isolates
| Antimicrobiala | Reading | Field isolates (n = 21)
|
Reference (J) strain
|
||
|---|---|---|---|---|---|
| MIC50 | MIC90 | MIC range | MIC range | ||
| LIN | Initial | ≤0.06 | ≤0.06 | ≤0.06->8 | <0.06 |
| Final | ≤0.06 | 0.12 | ≤0.06->8 | 0.25 | |
| LIN/SPT | Initial | ≤0.06/0.12 | ≤0.06/0.12 | ≤0.06/0.12-0.25/0.5 | <0.06/0.12 |
| Final | ≤0.06/0.12 | 0.12/0.25 | ≤0.06/0.12-0.25/0.5 | 0.12/0.25-0.25/0.5 | |
| SPT | Initial | 0.25 | 0.5 | ≤0.12-0.5 | 0.5 |
| Final | 0.5 | 1 | ≤0.12-1 | 1-2 | |
| OXY | Initial | 0.12 | 1 | 0.03-2 | 0.12 |
| Final | 0.5 | 2 | 0.12->2 | 1 | |
| DOX | Initial | 0.12 | 0.5 | 0.03-1 | 0.06-0.12 |
| Final | 0.5 | 1 | 0.12-2 | 0.5-1 | |
| ENRO | Initial | 0.03 | 0.5 | 0.015->1 | 0.015-0.03 |
| Final | 0.06 | 0.5 | 0.03->1 | 0.06 | |
| FLUM | Initial | 1 | >16 | 0.25->16 | 0.5-1 |
| Final | 2 | >16 | 0.5->16 | 2 | |
| GEN | Initial | ≤0.12 | 0.5 | ≤0.12-1 | 0.25-0.5 |
| Final | 0.5 | 1 | ≤0.12-1 | 0.5-1 | |
| FFN | Initial | ≤0.12 | 0.25 | ≤0.12-0.5 | 0.25 |
| Final | 0.25 | 0.5 | ≤0.12-1 | 1 | |
| TIA | Initial | ≤0.015 | 0.12 | ≤0.015-0.12 | 0.03 |
| Final | 0.03 | 0.12 | ≤0.015-0.12 | 0.06 | |
| TIL | Initial | 0.25 | 0.5 | ≤0.25->16 | 0.25 |
| Final | 0.5 | 0.5 | ≤0.25->16 | 0.5 | |
| TYL | Initial | 0.03 | 0.06 | ≤0.015->1 | ≤0.015-0.03 |
| Final | 0.06 | 0.12 | ≤0.015->1 | 0.12 | |
a
All data are given in micrograms per milliliter. MICs for the reference strain (J strain) were determined three times, and the results are included in this table.
b
LIN, lincomycin; SPT, spectinomycin; OXY, oxytetracycline; DOX, doxycycline; ENRO, enrofloxacin; FLUM, flumequine; GEN, gentamicin; FFN, florfenicol; TIA, tiamulin; TIL, tilmicosin; TYL, tylosin.