Antibiotics Susceptibility Profile of Listeria Species Isolated from Poultry Wastes and Fishpond Water from Private and Institutional Farms in Ibadan, Nigeria

Introduction: Untreated waste being discharged into the environment due to proliferation of poultry and fish farms can constitute a public health threat to human. Listeria, an emerging pathogen is commonly associated with food. This study aimed at determining the antibiotic resistant pattern of Listeria species isolated from poultry droppings and fish pond water in Ibadan.

Materials and Methods: Poultry waste and fishpond water samples were collected between April and July, 2016. Listeria Selective Agar was used to isolate Listeria species and identified using conventional methods. Antimicrobial susceptibility testing was done using the Kirby-Bauer disk diffusion method against ampicillin, cloxacillin, amoxicillin, streptomycin, ceftriazone, chloramphenicol, ciprofloxacin, ofloxacin, sulfamethoxazole-trimethoprim and tetracycline.

Results: A total of forty samples were collected and 105 Listeria spp. isolated; 62.9% from poultry waste and 37.1% from fishpond water. From the institutional fish pond and poultry waste, 18.1% and 51.4% isolates were obtained while from private fish pond and poultry waste, 19.1% and 11.4% isolates respectively were obtained. The isolates were Listeria monocytogenes (27.6%), L. innocua (8.6%), L. ivanovii (16.2%) and other Listeria spp. (47.6%). All the isolates were resistant to ampicillin and ciprofloxacin; all L. monocytogenes, L. innocua and L. ivanovii were resistant to ceftriaxone, but 89.3% of the other Listeria spp. showed resistance. Furthermore, all (100%) the isolates obtained from private poultry farm were resistant to chloramphenicol while 53.3% were resistant to trimethoprim/sulfamethoxazole. Also, 12.2% of the isolates were found to be resistant to a combination of six antibiotics including: Ampicillin, amoxicillin, ceftriaxone, streptomycin and trimethoprim/sulfamethoxazole.

Conclusion: This study revealed that poultry waste and fish pond water from the selected farms could be a potential source for the transmission of multi-drug resistant bacteria to humans. Proper treatment of poultry waste and fish pond water should be ensured before discharge into the environment.