Categorization of antibiotic resistant bacterial populations from Shrimp and its culture environment of Andhra Pradesh, India

• Published in: Aquaculture 2025-01, Vol.595, p.741702, Article 741702
• Main Authors: Nadella, Ranjit Kumar, Panda, Satyen Kumar, Uchoi, Devananda, Kishore, Pankaj, Chintada, Balakrishna, V.R., Madhu, V.A., Minimol, Badireddy, Madhusudana Rao, Kuricheti, Pani Prasad, Raman, Ram Prakash, Mothadaka, Mukteswar Prasad
• Format: Article
• Language: English
• Subjects: Antibiotic resistance genes (ARGs); Antimicrobial resistance (AMR); Aquaculture environment; Horizontal gene transfer (HGT); Multiple antibiotic resistance (MAR) index; Shrimp farming
• ISSN: 0044-8486
• DOI: 10.1016/j.aquaculture.2024.741702

Antibiotic resistance is one of the major concern for rapidly growing food sectors including shrimp aquaculture. A total of 2304 heterotrophic bacteria were isolated, categorized and screened for antibiotic resistance. Identification by conventional and molecular methods confirmed the presence of sixteen bacterial genera with the predominance of Vibrio sp. (38.54 %), Bacillus sp. (19.79 %), Tenacibaculum sp. (6.46 %), Halomonas sp. (6.03 %) etc. in the shrimp ponds. The isolates showed highest resistance to oxytetracycline (Vibrio sp. 79.3 %), followed by ciprofloxacin & co-trimoxazole (Exiguobacterium sp. 66.66 %) and chloramphenicol & erythromycin (Microbacterium sp. 50 % & 66.7 %). Overall resistance by all bacteria was highest for oxytetracycline (22 %). Among different bacterial isolates, majority of Vibrio sp. exhibited resistance to all the five antibiotics that varied from 1.4 % to 87.5 % from all the sampling sites (A to L). Among different antibiotic resistant genes (ARGs) screened by PCR, the most prevalent was tetA (44 %) followed sul1 (11.8 %). Vibrio sp. and Bacillus sp. showed the presence of all screened ARGs. Shrimp aquaculture ponds harboured antibiotic resistant bacteria and act as a main reservoir of ARGs. [Display omitted] •Antibiotic-resistant bacteria were widely distributed in shrimp culture ponds.•Biochemical and 16S rRNA sequencing revealed Vibrio sp. being the dominant genera.•Bacterial isolates showed maximum resistance towards oxytetracycline (22 %).•Multi-drug resistance was observed in 6.38 % of bacterial isolates.•Vibrio sp. harboured all studied ARGs with highest prevalence of tetA (44 %) gene.