Study of total microbial count, coliform contamination, and the antibiotic resistance pattern of Escherichia coli strains in shrimp supplied in Kerman City

Shrimp, a valuable marine protein source, was assessed for microbial quality in Kerman stores over a 3-month period during fall 2021. Aerobic mesophilic bacteria, coliforms, fecal coliforms, and Escherichia coli were quantified in 21 raw shrimp samples. Additionally, antibiotic resistance profiles of 125 Escherichia coli isolates against nine antibiotics (cefotaxime, ciprofloxacin, nitrofurantoin, gentamicin, cefixime, amikacin, sulfamethoprim, ceftriaxone, and nalidixic acid) were evaluated via disk diffusion assay. Results indicated microbial counts ranging from 3.3×105 to 8×108 CFU/ml (5.52 to 8.9 log CFU/ml). Coliform counts varied from zero per gram in 19% of samples to 4383.97 per gram. Fecal coliforms ranged from 0.1898 to 0.32 per gram, absent in 42.86% of samples. E. coli was isolated from 57.14% of samples, exhibiting the highest resistance to nalidixic acid (16.8%) and the highest sensitivity to nitrofurantoin and amikacin (99.2%). While antibiotic resistance levels were not alarming, the presence of fecal coliforms and E. coli suggests inadequate hygiene, necessitating closer monitoring and adherence to proper protocols for catching, transportation, storage, and preparation of shrimp.