Validação de metodologia analítica por UPLC/MS-MS para avaliação da presença de resíduos de antimicrobianos em músculo de frangos de corte após tratamento

Abstract

In order to evaluate the presence and the levels of antimicrobial residues in the broiler chickens muscle, by ultra performance liquid chromatography-tandem mass spectrometry (UPLC/MS-MS), were used 320 broiler chickens from Cobb line, that were housed in 8 units (pens) containing 40 birds each. The treatments, were defined according to the antimicrobial provided to broilers via drinking water, and they were as follows: A) birds received no drug (control); B) birds that received enrofloxacin in the drinking water; C) birds that received sulfaquinoxaline via drinking water and D) birds that received oxytetracycline in drinking water. The drugs were provided to the animals on days 32, 33 and 34 of rearing. The birds of groups B, C and D were slaughtered on days 32, 33, 34, 35, 36, 38, 40, 42, 44 and 46 days of rearing, while birds in group A were slaughtered on days 35, 36 , 38, 40, 42, 44 and 46 to collect thigh and breast muscle samples for evaluation of antimicrobial residues used. The analytical method by UPLC/MS-MS was validated and showed high selectivity, linearity (correlation coefficient greater than 0.99), adequate accuracy, with recoveries ranging from 86.40 to 107.08%, limits of detection (LOD) from 1.76 to 6.71, limits of quantification (LOQ) ranging from 5.33 to 20.34, decision limit (CC) and detection capability (CC) ranging from 111.34 to 120.86 and the from 122.67 to 141.72 respectively. The results of the analysis of the broiler chicken muscle samples showed the presence of residues of antimicrobials at concentrations above the maximum residue levels (MRL) of each drug until the 36th day of rearing of the birds, that is, two days after the discontinuation of the medication. At the 38th day of rearing, the residue levels found were below the quantification limit of the method for the tested analytes. It was concluded that the UPLC/MS-MS method has the performance characteristics adequate and is suitable for detecting residues of enrofloxacin, ciprofloxacin, sulphaquinoxaline and oxytetracycline in broiler chicken muscle. Also, the residues of all studied antimicrobials are rapidly metabolized from broiler muscles, because after four days of withdrawal period, the levels found were lower than the limit of quantification of the method for the studied analytes.