Bacteriological assessment of sediments from catfish ponds in Monai, Southern Basin of Kainji Lake, New Bussa, Niger State, Nigeria.

Abstract

This research study carried out a quantitative and qualitative bacteriological investigations on sediments sampled from catfish ponds over three seasons: harmattan, hot and wet. Results for quantitative bacteriological analysis recorded high total viable bacterial counts in the sediment samples, with the highest counts observed during the wet season months of August (3.22 x 10⁸ CFU/g) and September (2.30 x 10⁸ CFU/g). Similarly, results for total and fecal coliform counts also revealed the highest counts in the study during these wet months: August and September, reaching means of 1600 coliforms/100g and 69-138 faecal coliforms/100g, respectively. The lowest mean bacterial counts of 2.92 x 107 cfu/g and 3.67 x 107 cfu/g were recorded in the months of January and February respectively (harmattan season). Overall, the study recorded a total of 39 bacterial isolates that were identified across the samples through cultural, microscopy and biochemical tests. The predominant species included Escherichia coli, Enterobacter sp., Bacillus sp., Pseudomonas sp., Klebsiella pneumoniae, Aeromonas hydrophila/Aeromonas sp., Salmonella sp. and Micrococcus sp. The high bacterial loads, particularly the high loads of coliforms during wet periods generally indicate potential fecal contamination and seasonal impacts on microbial water quality as a result of anthropogenic activities such as cattle grazing, animal husbandry activities as well as point and non-point sources of pollution around the cluster fish farm. These findings outlined the need for monitoring and mitigating measures to safeguard public health. This is important because some villagers in Monai still use the stretch of Kainji Lake as a drinking water source and this lake receives effluents from the catfish ponds.