Antibiotics use and gentamicin residues in commercial poultry and chicken eggs from Oyo and Lagos States, Nigeria

Abstract

Nigeria poultry industry is fast growing to meet the demand of the increasing population with overdependence on antibiotics for production leading to consumer safety and public health concerns. The antibiotic use in poultry farms and presence of gentamicin residues in chicken eggs from city markets of Southwest Nigeria were investigated. A semi-structured questionnaire was administered to 45 poultry farmers to determine the patterns of antibiotic use, knowledge of withdrawal periods and food safety implications. Furthermore, 270 egg samples from six retail markets in Oyo and Lagos states were analyzed with ELISA for gentamicin residues. Residue concentrations were compared with Student’s t test and ANOVA (p < 0.05). About 90% of the respondents reported they frequently administered antibiotics, 85% engaged in non-prescribed medication, and about 80% did not observe a withdrawal period before selling the eggs from treated chickens. In addition, 60% and 80% of pooled eggs from Oyo and Lagos states, respectively, contained gentamicin residues with means of 1461 ± 74 and 1350 ± 92 µg/kg, respectively. The mean residues obtained from the two states were higher than the maximum recommended residue limits. High levels of gentamicin residues, from unbridled use of antibiotics in poultry production, detected in retail eggs from markets rendered the eggs unsafe for human consumption. Therefore, regulatory control and veterinary supervision of antibiotic use are advocated to ensure Nigerian consumer protection.