ANTIBIOTIC-RE¬¬SISTANT MOTILE AEROMONADS ASSOCIATED WITH CULTURED INDIAN MAJOR CARPS, POND WATER AND POND SEDIMENT

ANTIBIOTIC-RESISTANCE IN MOTILE AEROMONADS

Abstract

The uproar in antimicrobial resistance (AMR) among the aquacultured environment has led to the isolation of multiple antibiotic-resistant (MAR) Aeromonas strains. The current study aimed at the enumeration of antibiotic-resistant Aeromonas in carps of aquacultured environment and market samples. Isolation of Aeromonas was also done in Rimler-Shotts agar supplemented with novobiocin followed by antibiotic-sensitivity assay against 12 broad-spectrum antibiotics. Five oxytetracycline-resistant strains were examined for the presence of three tetracycline-resistant genes (tetA, tetC and tetE). The presumptive Aeromonas counts on starch-ampicillin agar were determined as log 3.00-log 6.45/g in carps, log 3.00l-log 5.06/ml in pond water and log 3.30–log 5.14/g in pond sediment. Higher proportions of motile aeromonads from market carps were resistant to chloramphenicol, cefalexin, gentamycin, oxytetracycline and trimethoprim than the farmed carps. Aeromonas strains depicted 57 resistant profiles. About 88.43% of the Aeromonas strains were of the MAR group among which 12.15% and 4.67% were resistant to ≥6 and ≥7 antibiotic groups, respectively. Selected oxytetracycline-resistant strains were negative for targeted genes. The current study implied the high prevalence of AMR bacteria in cultured carps in West Bengal, India. Furthermore, the study indicated that motile aeromonads comprise an effective marker for monitoring AMR in freshwater aquatic environments.