Table 3. The chloramphenicol resistance gene detection in Escherichia coli isolated from aquaculture farm and rivers
| Lane | E. coli isolate | Chloramphenicol resistant gene |
| cat I (349 bp) | cat II (567 bp) | cat III (275 bp) | cat IV (451 bp) |
| 1 | Positive control | + | + | – | – |
| 2 | RBK-S2-A | – | + | – | + |
| 3 | RDM-S1-A | – | + | – | + |
| 4 | RDM-S2-A | + | + | – | – |
| 5 | RDM-S3-A | + | + | – | – |
| 6 | RWF-S1-A | – | + | – | + |
| 7 | RSN-S1-A | – | + | + | – |
| 8 | RSN-S2-A | – | + | + | – |
| 9 | FAS-RV1(S) | – | + | – | + |
| 10 | FBK2-OLT(B) | – | + | – | + |
| 11 | FBK2-K2 | – | + | + | – |
Positive control, DUS-WF-6; +, indicates the presence of cat genes; –, indicate the absence of cat genes.