Salmonella spp. and antimicrobial residues in eggs from caged and cage-free systems in Colombia: labeling, production, and responsible food consumption

Background: The intensification of poultry farming poses challenges to food safety, animal welfare, and sustainability. Eggs, which are a source of high-quality protein, require sustainable production systems that ensure quality, safety, and animal welfare. Aim: To evaluate the presence of Salmonella spp. and antimicrobial residues in cage and cage-free eggs sold in Bogotá, and to analyze their labeling. Methods: A total of 100 samples (50 from cage and 50 from cage-free production systems, with each sample consisting of 20 eggs) were analyzed using lateral flow immunochromatography to detect Salmonella spp., and a microbiological inhibition test to identify residues of four families of antimicrobials. Labeling information was evaluated. Results: Salmonella spp. was detected in 19% of the samples, most frequently in those from caged systems. Antimicrobial residues were found in 50% of the samples, with a higher proportion in cage-free systems. No significant differences were observed between the two production systems. Cage-free system producers provided more information on their labels. Conclusions: There were no significant differences between housing systems and the presence of Salmonella spp. or antimicrobial residues, highlighting the risks of both systems. More information was provided on the labels of cage-free eggs, although deficiencies in labeling were found in both systems. Responsible food production and consumption should be promoted, which requires rigorous labeling.