2Faculty of Veterinary Medicine, University of Zaragoza, C/ Miguel Servet, 177, 50013 Zaragoza, Spain.
3Agrifood Research and Technology Centre of Aragon (CITA), Montañana, 930, 50059 Zaragoza, Spain.
4S.A.T. Num 42 Los Gonzalez, C/ Extramuros, s/N, 44300 Monreal del Campo, Spain.
Methodology: 4849 samples were evaluated with a methodology that combines a broad spectrum microbial test (Explorer) and a specific test for quinolones detection (Equinox). Supplementary tests were performed to achieve additional information about the nature of antimicrobials in positive samples.
Results: In a first step, 355 samples (7.3%) showed a positive result in Explorer and/or Equinox tests. The highest incidence of positive samples was obtained in poultry (9.7%) while the lowest rate was found in porcine samples (3.4%). Half of the positive screening samples (53%) showed also a positive result with supplementary tests indicating that tetracyclines, aminoglycosides sulphonamides and quinolones might be present in these samples. Aminoglycosides were the predominant residues in poultry while tetracyclines were more frequent in bovine and porcine samples. Sulphonamides were the main family of residues found in ovine.
Conclusion: Our results suggest that the current strategies used for control of antimicrobial residues in muscle could not be adequate enough. In order to protect consumers from antibiotic exposition, it should be advisable to implement more efficient methods for the screening of antibiotic residues in muscle.