TABLE 4.
Frequencies of antimicrobial drug resistance phenotypes observed by number of drugs to which the isolates were resistant and their sources
| No. of drugs to which isolates were resistant (no. of isolates) | Resistance phenotypea | % of all isolates | Source(s)b |
|---|---|---|---|
| 0 (477) | None (pansusceptible) | 51.1 | 1, 2, 3, 4, 5 |
| 1 (309) | Su | 28.3 | 1, 2, 3, 4, 5 |
| T | 2.4 | 1, 3, 4, 5 | |
| A | 1.5 | 1, 2, 3, 4 | |
| S | 0.43 | 2, 4 | |
| Fox | 0.32 | 1, 2 | |
| Nal | 0.11 | 1 | |
| 2 (78) | Su T | 5.1 | 1, 2, 3, 4, 5 |
| S Su | 0.86 | 2, 3, 4 | |
| Fox Aug | 0.86 | 1, 2 | |
| A Su | 0.64 | 1, 2, 3 | |
| Su Cef | 0.32 | 3 | |
| Nal Su | 0.32 | 3 | |
| C S | 0.11 | 2 | |
| A Fox | 0.11 | 4 | |
| 3 (35) | A Fox Aug | 3.4 | 1, 2, 3, 4 |
| S T Kan | 0.11 | 1 | |
| Su T TrSu | 0.11 | 4 | |
| S T Aug | 0.11 | 3 | |
| 4 (8) | A Su Fox Aug | 0.43 | 1, 2 |
| C S Su T | 0.21 | 4 | |
| C Su T Nal | 0.11 | 4 | |
| A Su T Fox | 0.11 | 4 | |
| 5 (2) | A Su Fox Aug Cef | 0.11 | 2 |
| A C Su T Aug | 0.11 | 1 | |
| 6 (3) | C Su T TrSu Fox Aug | 0.11 | 4 |
| A Su TrSu Fox Aug Cef | 0.11 | 2 | |
| A C S Su T Aug | 0.11 | 4 | |
| 7 (7) | A C S Su T Fox Aug | 0.43 | 1, 2, 4 |
| A C S Su T Aug Cef | 0.21 | 4 | |
| A C Su TrSu Fox Aug Cef | 0.11 | 2 | |
| 8 (5) | A C S Su T Fox Aug Cef | 0.54 | 1, 4 |
| 9 (1) | A C S Su T TrSu Fox Aug Cef | 0.11 | 2 |
| 10 (9) | A C S Su T Fox Aug Cef Kan Gen | 0.75 | 1, 2 |
| A C S Su T Fox Aug Cef Axo Kan | 0.21 | 2 |
A, ampicillin; C, chloramphenicol; S, streptomycin; Su, sulfisoxazole; T, tetracycline; Fox, cefoxitin; Aug, amoxicillin-clavulanic acid; Nal, nalidixic acid; TrSu, trimethoprim-sulfisoxazole; Cef, ceftiofur; Axo, ceftriaxone; Kan, kanamycin; Gen, gentamicin.
1, hide swab collected in an abattoir from beef-type cows removed from the herd because of poor productivity; 2, hide swab collected in an abattoir from dairy-type cows removed from the herd because of poor productivity; 3, hide swab collected in an abattoir from feedlot origin cattle that had achieved desirable harvest characteristics; 4, fecal sample collected from feedlot cattle removed from the herd because of poor productivity; 5, fecal sample collected from feedlot cattle that had achieved desirable harvest characteristics.