Bacteriological study in association with antibiotic resistance and heavy metal of bacteria isolated from macrobrachium rosenbergii larvae waste

Abstract

A study was undertaken to investigate the presence of bacteria in Macrobrachium rosenbergii larvae waste at marine hatchery of University Malaysia Terengganu as well as to determine the correlation of antibiotic and heavy metal resistance patterns. Total plate count (TPC) were ranged from 87 x 102 i 1 to 7.07 x 10 2 g-1 . The isolates were comprised Aeromonas spp, Pseudomonas spp, Salmonella sp., E.coli, Klebsiella sp., and Vibrio spp. which identified based on morphological typing by using selective agar such as Eosin Methylene-blue Lactose Sucrose Agar (EMB), Xylose Lysine Deoxycholate Agar (XLD), MacCONKEY agar, Thiosulphate Citrate Bile Sucrose Agar (TCBS) and Pseudomonas Aeromonas Selective Agar Base (GSP). The non selective agar was Trypticase Soy Agar (TSA) (Oxoid, England). Antibiotic succeptibility were conducted by using 15 different antibiotics that were commonly used in hatcheries. Results showed that Sulphamethioxazole (CT 25) was 82.5% sensitive to all isolates. Heavy metal test were conducted by using five different heavy metals with five different concentrations. Results showed that Hg and Cr were the best tolerated metals. The percentage of bacterial isolates resistance to heavy metal was 100%. This study was initiated as a preliminary attempt to establish the normal bacterial counts and aerobic, heterotrophic microflora found in larvae waste of freshwater prawn hatcheries in Malaysia and thus the antibiotic and heavy metal that resistant to the bacteria. This information will help in the future assessment of significance of isolates from diseased larvae in epizootic bacterial diseases. It is important to understand the bacteria associated with hatchery systems because the host-microbe interactions have far reaching implication on larval health, development and outbreaks of disease.