Preliminary evaluation of antimicrobial residue levels in marketed pork and chicken meat in the Red River Delta region of Vietnam.

The presence of antibacterial in 97 pork and 83 chicken meat samples, rando mly collected fro m 3 different representative provinces (Hanoi, Hai Duong and Thai Binh) of the Red River Delta, was determined by a screening step using in parallel 2 microbiological methods (Premi ® -test and New Two Plate Test). In total, 27% of all samples displayed a positive response in at least one of both tests, from which 11 (13% of chicken samples) are ch icken samples and 38 (39% of pork samples) are pork samples. The 33 samples fro m the Thai Binh which were screened positive were then submitted to post-screening tests specific for tetracyclines and (fluoro) quinolones (Tetrasensor ® dipstick for tetracyclines and an ELISA for quinolones), two groups of antibiotics widely used in animal production in this region, and confirmed by liquid chromatography coupled to mass spectrometry. Tetracyclines and (fluoro)quinolones residues were found, using a post screening test, in 23 and 5 samp les, respectively. Ten (all pork) and 4 samples (1 pork, 3 chicken) were confirmed containing tetracyclines (chlortetracycline, o xytetracycline, tetracycline, do xycycline) and (fluoro) quinolones (nalidixic acid, enroflo xacin and ciproflo xacin) respectively, fro m which 1 and 3 pork samples were found to contain enrofloxacin and tetracycline residues , respectively, with a concentration higher than their respective MRLs. This study shows the good performance of the proposed strategy to identify non-co mpliant meat samples (microbiological screening, tetracyclines and quinolones targeted post-screening and confirmation), which allows to obtain conclusive results in 82% of the cases.