Prevalence of Antimicrobial Residues in Tissues of Broilers Sold at a Local Market in Enugu State, Nigeria Using the European Four Plate Test

ABSTRACT Background Consumption of animal tissues treated with antimicrobial agents may be deleterious if they contain violative levels of the residues. This study determined antimicrobial residues prevalence in broilers sold at Ikpa market, Nsukka, Nigeria. Methods Tissues from muscle, liver and kidney of 60 commercial broilers (180 samples) were tested for antimicrobial residues using the conventional Four Plate Test. Result Prevalence of 80.0% (48/60) and 51.7% (93/180) was recorded in the birds and samples {muscle 40.0%(24/60); liver 55.0%(33/60) and kidney 60.0%(36/60)} respectively. There was no significant association between residue occurrence and tissue type (χ 2 (2) = 5.206; p = 0.074). Possible antimicrobial classes detected were: macrolid (50.0%) at pH 8.0 with Micrococcus luteus; β-lactams and tetracyclines (64.4%) with Bacillus subtillis at pH 6.0; sulphonamides (53.3%) at pH 7.2 with Bacillus subtillis , and aminoglycosides (46.8%) at pH 8.0 with Bacillus subtillis . Twenty-four tissue samples were positive at all four pH levels indicating use of more than one class of antimicrobials during each treatment. Conclusion Antimicrobial residues were detected in commercial broilers (muscles, liver and kidney) sampled at Ikpa Market, Nsukka. This is of public health importance given that antimicrobial residues are not monitored in poultry consumed in Nigeria.