Occurrence and levels of multiple veterinary antibiotics in broiler chicken processed and sold in Southern Mozambique

Abstract

Antibiotic residues in chicken meat pose a health risk to the general public, particularly to sensitive consumers. The aim of this study was to determine the level of antibiotic residues in on-the-market dressed chicken in the Southern Region of Mozambique. A total of 160 samples were randomly collected from eight markets located in five districts in the provinces of Maputo, Gaza, and Inhambane. The residues of β-lactams, quinolones, tetracyclines, and sulfonamides in chicken breast muscle were separated, identified, and quantified using high-performance liquid chromatography (HPLC), coupled with ultraviolet light (UV–VIS). Results revealed that 26.9% of the analyzed samples displayed detectable antibiotic residues, with 14.4% classified as mono-contaminated and 12.5% as poly-contaminated. Oxytetracycline prevailed (19.4%) and had the highest concentration (84–636 µg/kg), followed by trimethoprim (9.4%) and sulfamethoxazole (7.5%). Although the majority of samples adhered to the criteria established by Codex and EU, 100% of positive sample, exceeded the maximum residue limits for trimethoprim, with an average contamination level of 197 µg/kg. The presence of antibiotics in chicken breast meat at levels above maximum residue limits represents a risk to public health, reflecting even higher concentrations in risky parts like gizzard and liver, which are delicacies in Mozambique. This study suggests the implementation of a rigorous monitoring system across the chicken value chain (including farms, transportation, and slaughter facilities) to prevent the indiscriminate use of antibiotics in chickens.