Prevalence and Antimicrobial Resistance Profiles of Salmonella Species and Escherichia coli Isolates from Poultry Feeds in Ruiru Sub - County, Kenya

Abstract Objectives: Contaminated poultry feeds can be a major source of E. coli and Salmonella infections in poultry. This study aimed at determining the microbial quality, prevalence and antimicrobial resistance and associated resistance genes to Salmonella and E. coli isolates from poultry feeds.Results: A total of 150 samples of different poultry feed types were randomly collected from selected sites within Ruiru Sub-County. A microbial load was determined, Salmonella and Escherichia coli were isolated and antimicrobial susceptibility test accomplished. Antimicrobial resistance genes; TEM, SHV, strB and Dfr were established. Out of analyzed samples, 58% contained Escherichia coli and 28% Salmonella. Bacterial load ranged between 3.1 x105 cfug to 3.0 x106 cfu/g. The highest resistance was found with ampicillin (41%) for Salmonella and (62%) for E. coli isolates. All the Ampicilin resistant isolates carried TEM and SHV genes. In addition, strB and Dfr drug resistance genes associated with streptomycin and Cotri-moxazole were analysed. All isolates were susceptible to chloramphenicol and ciprofloxacin. The study reveals high bacterial contamination, presence of beta-lactamase, aminoglycoside and sulphonamide resistance genes across isolates from poultry feeds. Therefore, contaminated poultry feeds with bacteria are likely to lead to increase and spread of antimicrobial resistant strains across the community.