Table 2.
Observed results for susceptibility testing of non-type-specific E. coli and M. haemolytica in two sample sets using broth microdilution and disk diffusion
| Non-type-specific E. coli | M. haemolytica | |||||||
|---|---|---|---|---|---|---|---|---|
| Ampicillin | Ceftiofur | Streptomycin | Sulfisoxazole | Tetracycline | TMP-SMX | Ampicillin | Tetracycline | |
| Sample set 1 | ||||||||
| Resistant by both tests | 22 (1·9%) | 0 (0%) | 41 (3·5%) | 57 (4·9%) | 161 (14·2%) | 0 (0%) | 3 (0·7%) | 16 (3·7%) |
| Resistant only by disk diffusion | 1 (0·1%) | 0 (0%) | 4 (0·3%) | 3 (0·3%) | 25 (2·2%) | 0 (0%) | 1 (0·2%) | 0 (0%) |
| Resistant only by broth microdilution | 14 (1·2%) | 6 (0·5%) | 35 (3·0%) | 16 (1·4%) | 37 (3·3%) | 2 (0·2%) | 0 (0%) | 5 (1·2%) |
| Non-resistant by both tests | 1093 (96·7%) | 1131 (99·5%) | 1076 (93·1%) | 1082 (93·4%) | 909 (80·3%) | 1148 (99·8%) | 429 (99·1%) | 412 (1·2%) |
| Sub-total | 1130 (100%) | 1137 (100%) | 1156 (100%) | 1158 (100%) | 1132 (100%) | 1150 (100%) | 433 (100%) | 433 (100%) |
| Sample set 2 | ||||||||
| Resistant by both tests | 48 (4·2%) | 0 (0%) | 215 (18·8%) | 310 (26·7%) | 809 (73·2%) | 10 (0·9%) | 2 (0·6%) | 21 (6·0%) |
| Resistant only by disk diffusion | 1 (0·1%) | 1 (0·1%) | 25 (2·2%) | 10 (0·9%) | 59 (5·3%) | 3 (0·3%) | 0 (0%) | 3 (0·9%) |
| Resistant only by broth microdilution | 15 (1·3%) | 4 (0·3%) | 92 (8·0%) | 25 (2·2%) | 42 (3·8%) | 3 (0·3%) | 1 (0·3%) | 15 (4·3%) |
| Non-resistant by both tests | 1085 (94·4%) | 1153 (99·6%) | 814 (71·0%) | 813 (70·2%) | 196 (17·7%) | 1142 (98·5%) | 347 (99·1%) | 311 (88·8%) |
| Sub-total | 1149 (100%) | 1158 (100%) | 1146 (100%) | 1158 (100%) | 1106 (100%) | 1158 (100%) | 350 (100%) | 350 (100%) |
TMP-SMX, Trimethoprim-sulfamethoxazole.