Table 1.
Minimum inhibitory concentration (MIC) distribution and resistance rates among Serratia spp. and Citrobacter spp. isolates from dogs and cats.
| Agents | Genera (No. of Isolates) | MIC (µg/mL) | No. of Resistance (%) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.031 | 0.063 | 0.125 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | 64 | 128 | 256 | >256 | |||
| CPL | Serratia (30) | 30 | 30 (100) * | ||||||||||||||
| Citrobacter (23) | 2 | 2 | 1 | 1 | 4 | 2 | 1 | 10 | 18 (78.3) | ||||||||
| CMZ | Serratia (30) | 2 | 9 | 10 | 5 | 4 | 4 (13.3) | ||||||||||
| Citrobacter (23) | 1 | 3 | 1 | 1 | 5 | 5 | 6 | 1 | 7 (30.4) | ||||||||
| CTX | Serratia (30) | 2 | 14 | 13 | 1 | 0 (0.0) | |||||||||||
| Citrobacter (23) | 3 | 6 | 6 | 1 | 1 | 1 | 2 | 1 | 2 | 8 (34.8) * | |||||||
| MPM | Serratia (30) | 4 | 25 | 1 | 0 (0.0) | ||||||||||||
| Citrobacter (23) | 19 | 3 | 1 | 0 (0.0) | |||||||||||||
| TET | Serratia (30) | 1 | 1 | 2 | 7 | 14 | 5 | 26 (86.7) * | |||||||||
| Citrobacter (23) | 1 | 15 | 1 | 2 | 1 | 1 | 2 | 4 (17.4) | |||||||||
| AMK | Serratia (30) | 4 | 3 | 20 | 3 | 0 (0.0) | |||||||||||
| Citrobacter (23) | 2 | 5 | 13 | 2 | 1 | 0 (0.0) | |||||||||||
| CHL | Serratia (30) | 2 | 14 | 10 | 2 | 1 | 1 | 4 (13.3) | |||||||||
| Citrobacter (23) | 17 | 4 | 1 | 1 | 2 (8.7) | ||||||||||||
| CIP | Serratia (30) | 4 | 4 | 16 | 4 | 1 | 1 | 0 (0.0) | |||||||||
| Citrobacter (23) | 6 | 2 | 2 | 3 | 1 | 1 | 2 | 2 | 3 | 1 | 6 (26.1) * | ||||||
| 0.125/0.063 | 0.25/0.125 | 0.5/0.25 | 1/0.5 | 2/1 | 4/2 | 8/4 | 8/16 | 32/16 | 64/32 | 128/64 | 256/128 | >256/128 | |||||
| ACV | Serratia (30) | 1 | 3 | 1 | 2 | 15 | 8 | 25 (83.3) | |||||||||
| Citrobacter (23) | 3 | 2 | 4 | 5 | 9 | 14 (60.9) | |||||||||||
| ≤0.03/0.59 | 0.06/1.19 | 0.13/2.38 | 0.25/4.75 | 0.5/9.5 | 1/19 | 2/38 | 4/76 | 8/152 | 16/304 | 32/608 | 64/1216 | >64/1216 | |||||
| TMS | Serratia (30) | 4 | 5 | 18 | 3 | 0 (0.0) | |||||||||||
| Citrobacter (23) | 9 | 5 | 1 | 2 | 1 | 1 | 1 | 3 | 4 (17.4) * | ||||||||
CPL, cephalothin; CMZ, cefmetazole; CTX, cefotaxime; MPM, meropenem; TET, tetracycline; AMK, amikacin; CHL, chloramphenicol; CIP, ciprofloxacin; ACV, amoxicillin–clavulanic acid; TMS, trimethoprim–sulfamethoxazole. Vertical lines indicate breakpoints of each drug according to the Clinical and Laboratory Standards Institute guideline [10]. * Significant differences in resistance rates between Serratia spp. and Citrobacter spp. (p < 0.05).