Bacteriological load and antibiotic susceptibility patterns of bacterial isolates from aquatic resources harvested from Okwan Obolo estuary, Akwa Ibom State

This study was conducted to determine bacteriological load and antibiotic susceptibility profile of isolates from aquatic resources harvested from Okwan Obolo estuary, Akwa Ibom state, using standard microbiological techniques. The aquatic resources used were the fresh land crab (Gecarinus quadratus), Pallid Ghost crab (Ocypode pallidulla) and fishes (Sadinella maderensis) samples. The bacterial load of each sample was determined using serial dilution and pour plating techniques. Antibiotic sensitivity test was conducted using Kirby-Bauer Agar-disc diffusion method. The results indicated the highest mean of total heterotrophic bacterial counts(THBC), total Vibrio count (TVC), total coliform count (TCC) and total fecal coliform count(TFCC) ranges of 1.15 x105 CFU/g, 4.9x105 CFU/g 6.9 x105 CFU/g, 5.25 x105 CFU/g for Gecarinus quadratus 1, 1.16 x105 CFU/g, 4.4 x105 CFU/g, 6.5 x105 CFU/g, 5.75 x105 CFU/g for Ocypode pallidulla 1. Mean bacterial load from different anatomical sites of Sadinella maderensis ranged from 4.1 x 105 CFU/g, 1.6 x 105 CFU/g, 3.3 x 105 CFU/g and 2.6x 105 CFU/g for Sadinella maderensis1, 4.4 x 105 CFU/g, 2.6x 105 CFU/g, 2.8x 105 CFU/g, 2.0 x 105 CFU/g for Sadinella maderensis2 respectively. The isolates recovered were Vibrio parahaemolyticus, Vibrio vulnificus, Escherichia coli, Enterococcus spp, Staphylococcus aureus, Salmonella spp, Micrococcus spp, Coagulase- negative Staphylococcus (CON Staphylococcus), Bacillus spp, Enterobacter  spp, Pseudomonas spp and Proteus species. However, guts samples had the highest number of bacterial loads and isolates. Staphylococcus aureus had the highest percentage of occurrence (14.1%), closely followed by Escherichia coli and Micrococcus spp (12.5%) respectively. All the isolates recorded 100% sensitivity to amoxicillin-clavulanic antibiotics. CON Staphylococcus and Proteus spp recorded 100% sensitivity to all drugs tested while Escherichia coli recorded 100% to imipenem, gentamicin, ceftriazole and amoxicillin-clauvalanic antibiotics respectively. Proper cooking of aquatic resources is encouraged, and good water quality should be maintained in the estuary.