Bacterial are essential components of aquatic ecosystems, performing critical ecological functions while influencing the health of their hosts. As aquaculture remains the fastest-growing food sector, ensuring the bacteriological safety of freshwater fish is vital for both ecological stability and human health. This study aimed to isolate, characterize, and identify the bacterial diversity across the skin, fins, gills, and gastrointestinal tracts of eight freshwater fish species (in-cluding Catla catla, Labeo rohita, and various catfishes) collected from diverse water bodies in the Ganjam district of Odisha. Bacteriological profiling was conducted through isolation and identification using standard microbiological techniques. A total of 72 bacterial isolates were recovered. Antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion assay against 10 antibiotics from various classes, including carbapenems, polymyxins, and beta-lactams. Quantitative analysis revealed the highest bacterial load in the gut of Anabas testu-dineus (2.8 ×10⁷ CFU/ml), followed by the gut of Labeo species. Gram-positive bacteria were found to be more abundant than Gram-negative species. Identified genera included Bacillus sp., Lactobacillus sp., Staphylococcus sp., Streptococcus sp., and Micrococcus sp. (Gram-positive), as well as Aeromonas sp., Pseudomonas sp., and Proteus sp. (Gram-negative). Notably, E. coli and Vibrio sp. were absent in the samples. The antibiogram revealed significant resistance to Ampicillin, Penicillin-G, and Colistin, while Chloramphenicol remained effective against most isolates. The presence of multi-drug-resistant (MDR) bacteria in these commercially important fish species poses a serious public health concern. These findings underscore the need for improved aquaculture management and stringent food safety protocols to safeguard consumer health in the region.

Aquaculture, Ganjam, Antimicrobial Resistance, Bacteriological Profiling, Food Safety, Anabas testudineus