The monitoring of antibiotic use in animals is a crucial element to ensure food safety. Themain goal of this study was to analyse the distribution of selected antibiotics to porcine oral fluid,as well as to demonstrate that an oral fluid is an alternative to other biological matrices used inthe control of antibacterials. Therefore, an animal study with pigs treated using seven differentantibiotics was performed. Sulfadoxine (SDX) with trimethoprim (TRMP), lincomycin (LIN), tiamulin(TIAM), tylosin (TYL), amoxicillin (AMX) and penicillin G (PEN G) were injected intramuscularly topigs, and concentrations of these analytes in the oral fluid were assessed. Ultra-high-performanceliquid chromatography coupled with mass spectrometry (UHPLC-MS/MS) was used to quantify theanalytes. On the first day of medication, the highest concentrations for SDX and TRMP at the level of22,300 μg/kg and 14,100 μg/kg were found, respectively. The concentrations of LIN (10,500 μg/kg)and TIAM (7600 μg/kg) were also relatively high. The peak of TYL was recorded on the secondday of drug administration. Most of the analytes were present in oral fluid for 30 days, apart fromTYL, which was detected for 27 days. It was found that AMX and PEN G were quantified only for5 and 8 days, respectively, at very low concentrations. It was found that oral fluid can be used for theverification of antibiotics on pig farms (18) (PDF) UHPLC-MS/MS Analysis of Antibiotics Transfer and Concentrations in Porcine Oral Fluid after Intramuscular Application. Available from: https://www.researchgate.net/publication/358606554_UHPLC MSMS_Analysis_of_Antibiotics_Transfer_and_Concentrations_in_Porcine_Oral_Fluid_after_Intramuscular_Application [accessed Feb 21 2022].