Bacterial Assessment and Isolation of Antibiotic Resistant Bacteria from the Indian Major Carp, Labeo rohita

Abstract

A bacteriological study of fish is critical to protecting people from potential hazards and serving as an indicator of water contamination. The study was carried out to investigate microorganisms from the Labeo rohita. A total bacterial load was measured in the skin, gills, and intestine. It had a total bacterial load (TBL) of 1.54×109 CFU/g on average. The intestine had the highest average TBL of 2.09×109 CFU/g, while the gill had the lowest average TBL of 1.08×109 CFU/g. Isolated bacteria were grouped based on colony characteristics and then subjected to morphological, physiological, and biochemical analysis for identification up to the genus or species level. Staphylococcus aureus and Vibrio spp. were identified as the two microorganisms. After a thorough examination and PCR analysis, the two bacteria, S. aureus and Vibrio spp., were isolated. S. aureus was detected in skin samples from R3 and R5 fish. S. aureus was isolated from R3, R4, and R5 in the gills. S. aureus was found in intestinal samples R2, R3, R4, and R5. The presence of Vibrio spp. was found in the intestines of all fish samples tested, as well as the skin of R4 and R5, and the gills of R2, R3, R4, and R5. The 16S rRNA gene was amplified in all S. aureus isolates, while the Tox-R gene was amplified in all Vibrio spp isolates. The isolated S. aureus and Vibrio tested positive for the 16s rRNA and Tox-R genes, respectively. An antibiotic sensitivity test revealed that the majority of S. aureus and Vibrio spp were susceptible to azithromycin, ciprofloxacin, and tetracycline but resistant to amoxicillin and streptomycin.