TABLE 3.
Antimicrobial resistance and molecular characterization of C. coli isolates isolated from swine in this study
| Isolate ID | Production system | Processing stage | MIC (μg/ml)
|
Resistance patternb | Mutationc
|
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| CHL (32)a | CIP (4) | ERY (8) | GEN (16) | NAL (32) | TET (16) | Thr 86 Ile | 23S rRNA gene | ||||
| 49 | ABF | Nursery | 4 | 0.25 | 8 | 2 | 32 | >32 | ERY NAL TET | − | − |
| 260 | ABF | Nursery | 8 | 8 | 4 | 8 | >128 | >32 | CIP NAL TET | − | − |
| 952 | ABF | Finishing | 16 | 2 | >32 | 2 | >128 | >32 | ERY NAL TET | − | − |
| 966 | ABF | Finishing | 8 | 2 | 16 | 2 | >128 | >32 | ERY NAL TET | − | + |
| 1005 | ABF | Finishing | 4 | 1 | >32 | 1 | >128 | >32 | ERY NAL TET | − | + |
| 4075 | ABF | Finishing | 8 | 8 | 4 | 8 | >128 | >32 | CIP NAL TET | − | − |
| 4076 | ABF | Finishing | 8 | 8 | 4 | 8 | >128 | >32 | CIP NAL TET | − | − |
| 3804 | ABF | Finishing | 8 | 4 | >32 | 2 | 64 | >32 | CIP ERY NAL TET | − | − |
| 461 | Conventional | Nursery | 4 | 4 | >32 | 16 | >128 | >32 | CIP ERY GEN NAL TET | − | + |
| 475 | Conventional | Nursery | 8 | >4 | >32 | 2 | 128 | >32 | CIP ERY NAL TET | + | + |
| 524 | Conventional | Nursery | 8 | >4 | >32 | 8 | >128 | >32 | CIP ERY NAL TET | + | + |
| 525 | Conventional | Nursery | 8 | 64 | >32 | 1 | 128 | >32 | CIP ERY NAL TET | + | + |
| 526 | Conventional | Nursery | 8 | 64 | >32 | 1 | 128 | >32 | CIP ERY NAL TET | + | + |
| 548 | Conventional | Nursery | 2 | >64 | >32 | 1 | 128 | >32 | CIP ERY NAL TET | + | + |
| 549 | Conventional | Nursery | 2 | >64 | >32 | 2 | 128 | >32 | CIP ERY NAL TET | + | + |
| 552 | Conventional | Nursery | 4 | >64 | >32 | 2 | 128 | >32 | CIP ERY NAL TET | + | + |
| 554 | Conventional | Nursery | 4 | >64 | >32 | 2 | 128 | >32 | CIP ERY NAL TET | + | + |
| 555 | Conventional | Nursery | 4 | >64 | >32 | 2 | 128 | >32 | CIP ERY NAL TET | + | + |
| 459 | Conventional | Finishing | 8 | 0.5 | >32 | 1 | 32 | >32 | ERY NAL TET | − | + |
| 4516 | Conventional | Finishing | 32 | 4 | >32 | 1 | 128 | >32 | CHL CIP ERY NAL TET | − | + |
| 4517 | Conventional | Finishing | 32 | 4 | >32 | 1 | 128 | >32 | CHL CIP ERY NAL TET | − | + |
a
Breakpoint level based on C. jejuni ATCC 33560 in μg/ml antimicrobial concentration.
b
CHL, chloramphenicol; CIP, ciprofloxacin; ERY, erythromycin; GEN, gentamicin; NAL, nalidixic acid; TET, tetracycline.
c
Point mutations in gyrA and the 23S rRNA genes coding for ciprofloxacin and erythromycin resistance, respectively. All isolates were positive for the tet(O) gene.