BACTERIOLOGICAL ASSESSMENT OF FISH PONDS IN BENIN METROPOLIS

ABSTRACT

A fish pond is a man-made lake or reservoir designed specifically for breeding fish. Fishes are raised in various containments such as concrete, earthen, or plastic ponds. Water sources such as well water, rivers, lakes, borehole and stored water supplied into the fish pond could serve as pathways for microorganisms. These organisms include; bacteria, virus, fungi and nematodes. The aim of this study was to assess bacterial population in pond water from selected fish farms in Ikpoba Okha axis, Benin City, Nigeria. A total of twenty (20) pond water samples were collected and analyzed using standard culture methods. The total heterotrophic bacterial count was determined using the pour plate methods. Enumeration of the bacterial isolates was carried out and the mean counts were expressed as colony-forming units per millilitre (CFU/mL). The total heterotrophic bacterial count from the different fish ponds ranged from 24.5 ± 0.9 ×107 to 104.5 ± 1.7 ×107 CFU/mL. The highest count was recorded from pond 10 the lowest count from pond 14 respectively. The bacterial species isolated in this study include Staphylococcus spp, Enterococcus spp, Vibrio spp, Pseudomonas spp, Escherichia coli, Aeromonas spp and Proteus spp. The highest diversity of bacterial count was observed in earthen pond water and Tarpaulin pond water that were changed bi-monthly or ≥ monthly basis while the least diversity of bacterial count was observed in concrete and plastic pond water that were changed on a daily basis. The presence of the bacteria isolated from this study shows lack of qualitative pond management practices in the farms examined and this could pose great health implication on the fishes and consumers. Hence, the need to implement suitable control measures to prevent the proliferation of bacterial in aquaculture environments.