DOI: 10.1128/AEM.00204-13
Article Figures & Data
Figures
- Fig 1
Distribution of β-lactamase genes in 184 ESBL-producing E. coli isolates and 48 AmpC-producing E. coli isolates from mixed dairy and beef cattle farms and beef cattle farms.
- Fig 2
ESBL-producing E. coli isolates resistant to one or more classes of antimicrobial substances. The asterisk indicates that if an isolate was classified as intermediate for a group, it was categorized as resistant.
Tables
- Table 1
Numbers and distributions of samples collected from farms
Sample source (n) No. of samples Fecal (3/group) Boot swabs (1 pair/group) Dust (1/group) Mixed farms (30) Cows 90 31 29b Calves 89a 30 30 Beef cattle 89a 31 29b Sum 268 92 88 Beef cattle farms (15) Youngest group 45 15 15 Oldest group 45 16 14b Sum 90 31 29 Control group (10) Cow-calf herds (9) 27 9 3c Beef cattle farms (1) 6 2 2 Sum 33 11 5 - Table 2
Percentages of ESBL-producing E. coli-positive samples and confidence intervals
Sample source No. of samples/total (%) [CI] Fecal Boot swabs Dust Mixed farms Cows 37/90 (41.1) [31.5–51.4] 14/31 (45.2) [29.2–62.2] 5/29 (17.2) [7.6–34.6] Calves 50/89 (56.2) [45.8–66.0] 21/30 (70) [52.1–83.3] 12/30 (40) [24.6–57.7] Beef cattle 19/89 (21.4) [14.1–31.0] 12/31 (38.7) [23.7–56.2] 0/29 (0) [0.0–11.7] Sum 106/268 (39.6) [33.9–45.5] 47/92 (51.1) [41.0–61.1] 17/88 (19.3) [12.4–28.8] Beef cattle farms Youngest group 12/45 (26.7) [16.0–41.0] 3/15 (20) [7.1–45.2] 1/15 (6.7) [1.2–29.8] Oldest group 5/45 (11.1) [4.8–23.5] 5/16 (31.3) [14.2–55.6] 0/14 (0) [0.0–21.5] Sum 17/90 (18.9) [12.1–28.2] 8/31 (25.8) [13.7–43.3] 1/29 (3.5) [0.6–17.2] Total sum for mixed farms and beef cattle farms 123/358 (34.4) [29.6–39.4] 55/123 (44.7) [36.2–53.5] 18/117 (15.4) [10.0–23.0] Control group 0/33 (0) [0.0–10.4] 3/11 (27.3) [9.8–56.6] 0/5 (0) [0.0–43.5] - Table 3
Resistance patterns of bovine ESBL-producing E. coli isolates
Antimicrobial(s) No. (%) of isolates from: Mixed dairy and beef cattle farms (n = 170) Beef cattle farms (n = 26) Susceptible Intermediate Resistant Susceptible Intermediate Resistant Ampicillin 0 0 170 (100) 0 0 26 (100) Cefazolin 0 0 170 (100) 0 0 26 (100) Cefuroxime 0 0 170 (100) 0 0 26 (100) Cephalexin 1 (0.6) 0 169 (99.4) 1 (3.9) 0 25 (96.2) Cefotaxime 1 (0.6) 7 (4.1) 162 (95.3) 0 4 (15.4) 22 (84.6) Ceftazidime 33 (19.4) 82 (48.2) 55 (32.4) 10 (38.5) 10 (38.5) 6 (23.1) Imipenem 170 (100) 0 0 26 (100) 0 0 Meropenem 170 (100) 0 0 26 (100) 0 0 Ertapenem 170 (100) 0 0 25 (96.2) 0 1 (3.9) Aztreonam 1 (0.6) 26 (15.3) 143 (84.1) 1 (3.9) 8 (30.8) 17 (65.4) Nitrofurantoin 164 (96.5) 0 (0) 6 (3.5) 23 (88.5) 0 3 (11.5) Gentamicin 78 (45.9) 5 (2.9) 87 (51.2) 22 (84.6) 0 4 (15.4) Tobramycin 73 (42.9) 0 97 (57.1) 19 (73.1) 0 7 (26.9) Amikacin 169 (99.4) 1 (0.6) 0 26 (100) 0 0 Ciprofloxacin 68 (40.0) 2 (1.2) 100 (58.8) 22 (84.6) 0 4 (15.4) Trimethoprim-sulfomethoxazole 48 (28.2) 0 122 (71.8) 14 (53.8) 0 12 (46.2) Piperacillin-tazobactam 141 (82.9) 5 (2.9) 24 (14.1) 22 (84.6) 0 4 (15.4) Amoxicillin-clavulanic acid 80 (47.1) 0 90 (52.9) 12 (46.2) 0 14 (53.8) Colistin 170 (100) 0 0 26 (100) 0 0 Fosfomycin 169 (99.4) 0 1 (0.6) 23 (88.5) 0 3 (11.5)
