TABLE 2.
MIC distributions and resistance rates of C. jejuni isolates from turkey farms
| Antimicrobial | No. of isolates inhibited at indicated concn (μg/ml)a
|
MIC50/MIC90(μg/ml) | No. (%) of resistant isolates | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | 64 | 128 | 256 | >256 | |||
| Ampicillin | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 76 | >256/>256 | 78 (97.5) |
| Chloramphenicol | 2 | 5 | 32 | 36 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 4/4 | 0 |
| Ciprofloxacin | 27 | 1 | 1 | 0 | 1 | 8 | 29 | 11 | 2 | 0 | 0 | 32/64 | 51 (63.75) |
| Erythromycin | 30 | 31 | 18 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1/2 | 0 |
| Gentamicin | 32 | 45 | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1/1 | 0 |
| Kanamycin | 0 | 0 | 1 | 8 | 29 | 7 | 0 | 1 | 0 | 1 | 33 | 16/>256 | 34 (42.5) |
| Nalidixic acid | 0 | 0 | 2 | 12 | 13 | 2 | 0 | 15 | 25 | 7 | 4 | 64/256 | 51 (63.75) |
| Streptomycin | 1 | 8 | 11 | 2 | 0 | 2 | 1 | 7 | 9 | 3 | 36 | 128/>256 | 48 (60) |
| Tetracycline | 2 | 3 | 8 | 1 | 1 | 0 | 2 | 5 | 28 | 21 | 9 | 128/>256 | 65 (81.25) |
a
Boldface numbers of isolates indicate that the corresponding MIC was the resistance breakpoint.