Investigation of antibiotic resistant vibrios associated with shrimp (Litopenaeus vannamei) farms

Abstract

Abstract For the sustainable farming of disease-free and healthy shrimps, antimicrobial usage is frequent nowadays in shrimp-cultured system. This could lead to the emergence of severe antimicrobial resistance (AMR) in the whole ecosystem. Considering the serious impact of global AMR, the present study was focused to investigate the prevalence of antimicrobial resistant vibrios among infected shrimps (Litopenaeus vannamei) from two brackish-water cultured farms. Diverse species of vibrios viz. V. alginolyticus, V. parahaemolyticus, V. cholerae, V. mimicus and V. fluvialis and other isolates such as Aeromonas hydrophila, A. salmonicida and Shewanella algae were also recovered from the shrimps on TCBS medium.Shannon wiener diversity index, H’ (loge) was found to be 1.506 for the isolates from farm 1 and 1.69 for those from farm 2. V. alginolyticus was found to be the most resistant isolate by showing MAR index of 0.60 followed by V. mimicus (0.54) and V. parahaemolyticus(0.42). Among the 35 antibiotics of 15 different classes tested, tetracyclines, beta lactams and cephalosporins were found as the most resistant antibiotic classes. An increased altered resistance phenotype and a drastic change in MAR index were noticed after plasmid curing. Since the studied shrimp samples are of significance in food sector and plasmid-borne AMR is evident among the isolates, public health is also alarming. This baseline information will help the authorities to curb the antimicrobial use and pave the way for establishing new alternative strategies by undertaking multidimensional “One-Health” approach.