Antibiotic Resistance and its Gene Profile in Escherichia coli Isolated from Diseased Farm- Raised Carps in Punjab, Pakistan

Antibiotic resistance has become alarming to public health. The present study aimed to investigate the multi-drug resistance (MDR) of Escherichia coli (E. coli) in farm-raised fish. A total of 216 diseased fish samples from different fish farms were screened for E. coli. Molecular confirmation was done with Polymerase chain reaction (PCR) using uspA gene. All the positive E. coli isolates were subjected to eight different antibiotics. Antimicrobial sensitivity was performed via the Kirby Bauer disk diffusion method. Antibiotic resistance genes; blaSHV blaTEM, blaCTX-M, tet(A), tet(B), erm (A), erm (B), erm (C), vga (A), str(A), str(B), aadA1 and aac (3)-I were examined. A total of 79 (36.57%) E. coli was confirmed through PCR. Antibacterial susceptibility test showed 86.1% of isolates were highly resistant towards oxytetracycline and 22.7% of isolates were sensitive against azithromycin, respectively. Results for all antimicrobial agents were highly significant p<0.01, except streptomycin. Phenotypic multi-drug resistant (MDR) was documented against 8 different antibiotics. About 7.59% of isolates stood resistant against eight different antibiotics. The higher prevalence for blaCTX-M was 86.07%, tetA 91.13%, and ermB 69.62% while for strA 75.94% was recorded. While blaSHV, ermA, and vga(A) genes were not detected. All isolates were recorded for genotypic MDR. About 10.12% of isolates were sustained for ten different antibiotic resistance genes. The results for antibiotic susceptibility and resistance genes pattern in the present study have provided a valuable check and balance in term of unhygienic practices and the misuse of antimicrobial agents.