Prevalence of Vibrio Spp and Antibiogram of Isolates from Shrimp Rearing Ponds in Bangladesh

Abstract

Forty eight water samples were collected from 12 shrimp rearing ponds in Khulna Division, southern part of Bangladesh. Fifteen Vibrio spp were isolated and identified and subjected to antibiotic susceptibility testing against ten commercial antibiotic disks. 58% water samples were found positive for Vibrio spp. Among the isolates V. fischeri (40%) were the most prominent, followed by V. vulnificus (27%), V. anguillarum (26%), and V. cincinnatiensis (7%). Most of the Vibrio isolates were found to tolerate as much as 6% concentrations of NaCl and could not grow in culture medium without added salt. Antibiotic resistance pattern showed the highest resistance to ampicillin (100%), followed by amoxicillin (78%), nalidixic acid (40%), vancomycin (13.33%), neomycin (6.66%) and chloramphenicol (6.66%). All the Isolates were observed sensitive to gentamycin, erythromycin, ciprofloxacin and doxycyclin. Plasmid profiling of the isolates were conducted to observe if there any association of large plasmids with antibiotic resistance. Only 3 isolates were found to carry plasmid. Among them Vibrio anguillarum/P3 harbored four plasmids of 2.7, 3.0, 3.9 and 5.1 Kbp, Vibrio anguillarum/P1 harbored one plasmid of larger than 7.3 kbp and Vibrio cincinnatiensis/ P5H harbored one plasmid of larger than 30 kbp.