Table 4.
Antimicrobial susceptibility of the study isolates to eight of the 12 antimicrobial agents tested.
| Antimicrobials | MIC50 | MIC90 | Range | Resistant, no. of isolates (%) | Intermediate, no. of isolates (%) | Susceptible, no. of isolates (%) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Farm A | Farm B | Total | Farm A | Farm B | Total | Farm A | Farm B | Total | ||||
| Penicillin | 0.06 | 8 | 0.06—32 | 13(17.8) | 17(73.9)* | 30(31.3) | 0(0) | 0(0) | 0(0) | 60(82.2) | 6(26.1) | 66(68.8) |
| Ciprofloxacin | 2 | 8 | 0.125—16 | 10(13.7) | 8(34.8)* | 18(18.8) | 52(71.2) | 0(0) | 52(54.2) | 11(15.1) | 15(65.2) | 26(27.1) |
| Enrofloxacin | 0.5 | 4 | 0.125—32 | 7(9.6) | 8(34.8)* | 15(15.6) | 7(9.6) | 0(0) | 7(7.3) | 59(80.1) | 15(65.2) | 74(77.1) |
| Tilmicosin | 2 | 2 | 0.5—64 | 2(2.7) | 4(17.4)* | 6(6.3) | 0(0) | 0(0) | 0(0) | 71(97.3) | 19(82.6) | 90(93.8) |
| Erythromycin | 0.25 | 0.25 | 0.125—16 | 1(1.4) | 4(17.4)* | 5(5.2) | 2(2.7) | 0(0) | 2(2.1) | 70(95.9) | 19(82.6) | 89(92.7) |
| Gentamycin | 1 | 1 | 0.5—64 | 1(1.4) | 0(0) | 1(1) | 0(0) | 0(0) | 0(0) | 72(98.6) | 23(100) | 95(99) |
| Chloramphenicol | 8 | 8 | 0.5—128 | 1(1.4) | 0(0) | 1(1) | 1(1.4) | 1(4.3) | 2(2.1) | 71(97.3) | 22(95.7) | 93(96.9) |
| Tetracycline | 0.5 | 0.5 | 0.25—64 | 1(1.4) | 0(0) | 1(1) | 1(1.4) | 0(0) | 1(1) | 71(97.3) | 23(100) | 94(97.9) |
| Fosfomycin | 32 | 64 | 0.5—256 | 0(0) | 0(0) | 0(0) | 1(1.4) | 0(0) | 1(1) | 72(98.6) | 23(100) | 95(99) |
| Ceftiofur | 0.5 | 2 | 0.25—64 | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 73(100) | 23(100) | 96(100) |
| Daptomycin | 0.5 | 1 | 0.06—16 | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 73(100) | 23(100) | 96(100) |
| Vancomycin | 0.5 | 1 | 0.06—128 | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 0(0) | 73(100) | 23(100) | 96(100) |
*
p < 0.05.