Determination of Sedatives and β-Blocker Residues in Bovine, Swine, and Equine Kidney by Liquid Chromatography Coupled to Tandem Mass Spectrometry

Sedatives and β-blockers are frequently utilized to mitigate stress in the transport of livestock, specifically pigs, with the goal of avoiding subpar meat quality and premature mortality. The unauthorized application of sedatives in animal farming seeks to improve the feed conversion ratio, fostering weight gain through the reduction of animal activity. The potential for residues in consumable tissues is increased due to the common practice of administering these substances shortly before the slaughtering process. A method for the determination of five sedatives (azaperol, azaperone, clorpromazine, acepromazine, and xylazine) and one β-blocker (carazolol) residue in swine, bovine, and equine kidney is detailed. Briefly, samples were extracted with acetonitrile and purified using dispersive solid phase extraction (d-SPE) with Celite 545 with subsequent analysis by LC-MS/MS. This protocol is part of the official Brazilian National Residue Control Plan since 2016 and has been applied for thousands of samples since then. The method is able to detect and quantify the analytes with detection limits from 1.25 to 2.5μg kg−1.