Bacteriological and physicochemical analysis of waste water from fish ponds

Abstract

Rearing of fish especially catfish is very common in many communities in Nigeria and the wastewater from these fish ponds are often discharged into the surrounding drains. Assessment of the bacteriological and physicochemical characteristics of ten freshwater fish ponds stocked with African catfish (Clarias gariepinus) was conducted within Ilorin metropolis. The results of physicochemical properties of the water samples showed that the pH, total hardness, salinity, and suspended solid ranged from 6.77 – 8.43, 65 – 124 mg/l, 7.02 – 10.062 g/l, and 0.012 – 0.128g/100ml respectively. The bacterial count, total coliform, and faecal coliform count of the wastewater  ranged  from  4.0 x 10³ – 6.7 x 10⁵cfu/ml, nil to 2 x 10⁴cfu/ml, and nil to 1 x 10³cfu/ml respectively. The bacterial species isolated from the ponds were Escherichia coli, Staphylococcus sp., Staphylococcus aureus, Aeromonas hydrophila, Staphylococcus saprophyticus, Chromobacterium sp, Micrococcus sp., Micrococcus kristinae, Providencia sp., and Listeria sp. The antibiotics susceptibility testing of the bacterial isolates were determined using the disc method. All the isolates exhibited multiple antibiotic resistance (MAR). It can be concluded from this study that there is need to monitor the quality of wastewater from the fish ponds before being discharged into the environment since potential pathogens were isolated and most of these  isolates were multiple antibiotic resistant. This study is of socioeconomic significance in the sense that while the farmers are able to raise their fish in the ponds and derive their livelihood, they are being cautioned on the need to treat their waste water before being discharged into the receiving water body.

Keywords: Wastewater, Fish pond, Catfish, Assessment, Antibiotic resistance