Antimicrobial drug usage and poultry production: case study in Ghana

Abstract

Antimicrobial use in food animal production could lead to the occurrence of antimicrobial residues in the animal products. In Ghana, there is no monitoring program for antimicrobial residue in foods of animal origin. We determined the types of antimicrobial drugs used in poultry production in Dormaa municipality and the levels of residue found in poultry products. Performing a cross-sectional study, a structured questionnaire and direct observation methods were used to assess antimicrobial usage, knowledge of and adherence to withdrawal periods in randomly selected poultry farms. Eggs and ready-for-sale broilers were purchased from selected respondents’ farms for detection and quantification of residues using the microbial inhibition plate assay. A total of 132 farmers were interviewed from 115 farms. Farms (86%) administered drugs to birds for prophylactic purposes. A total of 28 (24.3%) farms had tetracycline residue in eggs, 25 (21.7%) in kidney and 14 (12.2%) in liver. Mean (±s.d.) tetracycline concentration (μg/g) found were: eggs 0.02 ± 0.003; kidneys 0.02 ± 0.01; and liver 0.01 ± 0.008. Twenty-six farms (92.9%; ρ > 0.05) that had residues in eggs had sold eggs during treatment of the laying birds. A disinfectant and two antibiotics in human formulations were administered to birds in 44.3%, 17.4% and 2.6% farms respectively on an extra-label basis. Tetracyclines were the main antimicrobial drugs used in poultry farming in the study area with little or no regard to withdrawal periods. Tetracycline residue was found in poultry but below the Maximum Residue Level set by Codex Alimentarius. Extra-label use of disinfectant to water-medicate birds poses a health hazard to farmers and consumers alike.