Table 5. Enterococcus isolate antimicrobial resistance patterns by site and bacterial species.
| Control | Dairy | Beef A | Beef B | Antibiotics | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Species* | N | Bird** | Environment | Bird | Environment | Bird | Environment | Bird | Environment | TE*** | SXT | CN | E | P | VA |
| C | 1 | 1 | R | S | S | R | S | S | |||||||
| C | 2 | 1 (H) | 1 | R | S | S | I | S | S | ||||||
| C | 1 | 1 (H) | S | S | R | I | S | S | |||||||
| C | 1 | 1 (B) | S | S | I | I | S | R | |||||||
| C | 18 | 4 (C-2,H,M) | 1 | 1 (B) | 6 | 1 (B) | 5 | S | S | S | S/I | S | S | ||
| D | 6 | 1 (H) | 1 | 1 (H) | 3 | R | S | S | S/I | S | S | ||||
| D | 1 | 1 | S | S | I | R | S | S | |||||||
| D | 7 | 1 (G) | 1 | 1 (H) | 4 | 1 (B, H) | S/I | S | S/I | S/I | S | S/I | |||
| Fs | 1 | 1 | R | R | R | I | S | R | |||||||
| Fs | 1 | 1 (B) | R | R | R | R | S | I | |||||||
| Fs | 3 | 2 (A, S) | 1 | R | S | R | R | S | S/I | ||||||
| Fs | 1 | 1 (B) | S | S | R | R | S | R | |||||||
| Fs | 2 | 1 | 1 (O) | R | S | S | R | S | S | ||||||
| Fs | 1 | 1 | S | S | S | R | S | R | |||||||
| Fs | 1 | 1 (H) | S | S | R | I | S | R | |||||||
| Fs | 4 | 1 (M) | 1 | 1 (B) | 1 | R | S | S | S/I | S | S | ||||
| Fs | 2 | 1 | 1 | S | S | I | I | S | R | ||||||
| Fs | 7 | 1 (B)& | 1 | 1 (H) | 4 (B-3, S) | S | S | R | I | S | I | ||||
| Fs | 3 | 1 | 2 (B, H) | S | S | S/I | R | S | S | ||||||
| Fs | 24 | 3 | 6 (H-5, B) | 1 | 5 (R, S-4) | 1 | 8 (R, C-2, G-2,H, B-2) | S | S | S/I | S/I | S | S/I | ||
| Fm | 1 | 1 | R | I | R | R | S | I | |||||||
| Fm | 1 | 1 (H) | R | R | S | R | S | S | |||||||
| Fm | 3 | 2 (H) | 1 | R | S | S | I | R | S | ||||||
| Fm | 1 | 1 | R | S | S | R | S | S | |||||||
| Fm | 5 | 1 (B)$ | 4$ | R | S | S | S/I | S | S | ||||||
| Fm | 1 | 1 (H) | S | S | R | I | S | I | |||||||
| Fm | 3 | 1 (H) | 2 | S | S | S | R | S | S | ||||||
| Fm | 6 | 2 (H) | 4 | S | S | S | S/I | S | S | ||||||
| G | 1 | 1 (B) | R | S | S | I | S | I | |||||||
| G | 3 | 1 (H) | 1 | 1 | S | S | S | S/I | S | S/I | |||||
| H | 3 | 1 | 2 | R | S | S | R | S | S | ||||||
| H | 4 | 2 (C, M) | 2 (H) | R | S | S | S/I | S | S | ||||||
| H | 9 | 1 (H) | 1 | 3 | 4 | R | S | S/I | S/I | S | S | ||||
| H | 2 | 1 | 1% | S | S | S | R | S | S | ||||||
| H | 32 | 12 (C-2, G, H-6, M-3) | 5 | 2 | 2 (S) | 2 | 5 (C-2, B-3) | 4 | S | S | S | S/I | S | S | |
| All | 162 | 21 | 12 | 23 | 26 | 10 | 17 | 29 | 24 | ||||||
Notes:
Enterococcus species abbreviations: c, Enterococcus casseliflavus; d, Enterococcus durans; fs, Enterococcus faecalis; fm, Enterococcus faecium; g, Enterococcus gallinarum; h, Enterococcus hirae.
Bird identity abbreviations: A, gray catbird; B, red-winged blackbird; C, brown-headed cowbird; G, common grackle; H, house sparrow; M, mourning dove; O, song sparrow; P, grasshopper sparrow; R, American Robin; S, European starling.
Table 2 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; CN, gentamicin; E, erythromycin; P, penicillin G; VA, vancomycin.
SXT not tested for one isolate assigned to this profile due to laboratory error (one control house sparrow).
E not tested for two isolates assigned to this profile due to laboratory error (one each of a red-winged blackbird and environmental sample at the dairy site).
TE and SXT not tested for one isolate assigned to this profile due to laboratory error (one environmental sample from beef R).