Physicochemical Studies of Environmental Samples and Antimicrobial Susceptibility Profile of Escherichia coli Isolated from Akinyele Abattoir, Ibadan, Nigeria

Abstract

Introduction: Wastes generated from abattoirs contain pollutants including coliform that contaminates the environment. Aim: This study was designed to determine the physicochemical parameters of different environmental samples collected from an abattoir in Ibadan, South-western Nigeria. Materials and Methods: Samples were collected from well water, pond water, wastewater, cow dung and soil. The physicochemical analyses of the samples were carried out, the samples were serially diluted and using pour plate method, E. coli was isolated with MacConkey agar and Eosin Methylene Blue Agar. The antibiotic susceptibility test of the isolates was carried out using the disc diffusion technique against the following antibiotics: Tetracycline (30 µg), Oxytetracycline (30 µg), Nalidixic acid (30 µg), Nitrofuratoin (300 µg), Amikacin (30 µg), Ceftazidime (30 µg), Cefotaxime (30 µg) Chloramphenicol (30 µg), Ampicillin (10 µg), and Ciprofloxacin (5 µg). Results: The temperature and pH range of the water samples were between 29-30°C and 6.5-7.6 respectively, while the dissolved oxygen ranged between 0.02 mg/L and 9.7 mg/L. The biochemical oxygen demand ranged between 5.7 mg/L and 698.5 mg/L, whereas, the range of the turbidity was between 9.4 NUT and 1056.8 NUT. A total of 106 E. coli were isolated from the samples, out of which 55.7% showed resistance to ampicillin as against 1.9% that showed resistance to amikacin. Conclusion: The values of the physicochemical parameters that were above the limits coupled with the presence of multiple antibiotic resistant E. coli is an indication that the abattoir activities have been impacting negatively on the surrounding environment. Hence, adequate monitoring is required from the local authorities assigned to the management of the abattoirs to ensure that best abattoir practices are adhered to protect the health of the public.