Table 4. Escherichia coli isolate antimicrobial resistance patterns by site.
| N | Control | Dairy | Beef A | Beef B | Antibiotics | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bird* | Environment | Bird | Environment | Bird | Environment | Bird | Environment | TE** | SXT | KF | EFT | AM | RD | AZM | AMC | C | |
| 1 | 1 | R | R | R | R | R | S | S | R | R | |||||||
| 1 | 1 | R | R | I | S | R | R | S | S | R | |||||||
| 1 | 1 | R | S | R | S | R | S | S | S | R | |||||||
| 1 | 1 (H) | R | S | S | S | R | S | S | S | R | |||||||
| 1 | 1 | R | R | S | S | S | S | S | S | S | |||||||
| 2 | 1 | 1 | R | S | S/I | S | S | R | S | S | S | ||||||
| 1 | 1 (H) | R | S | S | S | R | S | S | S | S | |||||||
| 7 | 3 | 4 | R | S | S/I | S | S | S/I | S | S | S | ||||||
| 28 | 1 (M) | 3 | 3 (H) | 5 | 6 | 1 (G) | 9 | S | S | S/I | S | S | R | S | S | S | |
| 1 | 1 (H) | S | S | R | S | S | S | S | S | S | |||||||
| 1 | 1 (G) | S | R | S | S | S | S | S | S | S | |||||||
| 66 | 9 (C, G, H-2,M-5) | 10 (H-9,B) | 7 | 11 (R-2, E-6, A-2, P) | 18 | 4 (G, S, H, B) | 7 | S/I | S | S/I | S | S/I | S/I | S | S | S | |
| 111 | 11 | 3 | 16 | 16 | 11 | 27 | 5 | 22 | |||||||||
Notes:
Table 1 shows antibiotic resistance combinations observed within individual isolates for all antibiotics tested. An “R” in the antibiotics column indicates the isolates listed by count (with bird species-number indicated in parentheses) was resistant to the antibiotics. An “S” indicates the all isolates in the row were susceptible to the antibiotic. An “I” indicates that all isolates in the row were of intermediate status. An “S/I” indicates that some of the isolates in that row were susceptible and at least one isolate had an intermediate phenotype. Antibiotic abbreviations: TE, tetracycline; SXT, trimethoprim-sulfamethoxazole; KF, cephalothin; EFT, ceftiofur; AM, ampicillin; RD, rifampin; AZM, azythromycin; AMC, ampicillin with clavulinate; C, chloramphenicol.
Bird identity abbreviations: A, gray catbird; B, red-winged blackbird; C, brown-headed cowbird; G, common grackle; H, house sparrow; M, mourning dove; P, grasshopper sparrow; S, European starling.