Molecular Studies of Antibiotics Resistant Bacteria Contaminating Poultry Feeds in Enugu Metropolis, Nigeria: The Public Health Implications

Abstract

Background and Objectives: Poultry refers to all domesticated birds kept for egg laying or meat production. Poultry feeds are feedstuffs used in raising poultry birds. Unsafe feeds may cause chronic losses to farmers and also pose public health risk. This study was conducted to identify and characterize bacterial flora of poultry feeds. Materials and Methods: Locally milled and company branded poultry feeds were obtained within Enugu, Nigeria. A total of three hundred samples of poultry feeds were investigated for bacterial contamination and total bacterial counts. Susceptibility pattern of two bacterial isolates to commonly used antibiotics was determined in vitro employing standard disk diffusion method. Molecular studies of four bacterial isolates with multiple drug resistance were done using Agarose Gel electrophoresis for plasmid profiling, multiplex PCR was used to detect SHV and CTX-M gene while conventional linear PCR was used to detect TEM gene. Results: A total of six bacterial species were isolated and they were Escherichia coli, Klebsiella pneumonia, Bacillus cereus, Staphylococcus aureus, Enterococcus species and Yersinia specie. The total bacteria counts ranged from 1.92×10⁴–25.0×10⁶ CFU g^–1. Escherichia coli having the highest occurrence rate (45.7%) was highly resistant to tetracycline (92%), streptomycine (90%), neomycin (90%), ampicillin (80%) and chloramphenicol (78%). Molecular studies of the isolates showed presence of one plasmid DNA each with band weight of 17-18 kb. Escherichia coli and Klebsiella pneumonia were positive for SHV and TEM gene while only Escherichia coli were positive for CTX-M. Conclusion: Poultry feeds did not meet the international microbiological standards.