Table 5.
Changes in MICs of antimicrobial agents among Streptococcus uberis (n = 228) isolates from dairy cattle with bovine mastitis in northern Thailand during 2010–2017.
| Antimicrobial agents | MIC50/MIC90 (μg/mL) | |||||||
|---|---|---|---|---|---|---|---|---|
| 2010 (n = 9) | 2011 (n = 9) | 2012 (n = 32) | 2013 (n = 17) | 2014 (n = 57) | 2015 (n = 52) | 2016 (n = 18) | 2017 (n = 34) | |
| Ceftiofur | 4/4 | 2/8 | 2/4 | 2/8 | 4/8 | 4/8 | 4/4 | 8/32 |
| Tetracycline | >32/>32 | >32/>32 | >32/>32 | 4/>32 | >32/>32 | >32/>32 | >32/>32 | >32/>32 |
| Erythromycin | <0.0039/2 | <0.0039/2 | <0.0039/ <0.0039 | <0.0039/ <0.0039 | <0.0039/ <0.0039 | <0.0039/ <0.0039 | <0.0039/ <0.0039 | <0.0039/>2 |
| Gentamycin | 1/2 | 1/2 | 2/2 | 1/2 | 1/2 | 1/2 | 1/2 | 1/2 |
| Penicillin G | 0.0625/0.25 | 0.0078/0.0625 | 0.0078/0.0078 | 0.0078/0.0078 | 0.0078/0.03125 | 0.0078/0.0625 | 0.0078/0.03125 | 0.03125/0.5 |
MIC, minimum inhibitory concentration.