A simple method for the determination of chloramphenicol in 22 matrices was prepared based on the QuEChERS and HPLC-MS/MS combination. Following a hydrolysis step, the homogenized samples were extracted and partitioned after adding sodium chloride with acetonitrile. Chloramphenicol was analysed by HPLC-MS/MS in negative electrospray mode by monitoring the daughter ions m/z: 321→194 and 321→152. The limit of decision (CCα) was calculated at the range of 0.10 μg kg−1 to 0.15 μg kg−1 and detection capability (CCβ) from 0.12 μg kg−1 to 0.18 μg kg−1. Validation results showed that this method is suitable for the determination and confirmation of chloramphenicol in various matrices.

A 3-year-old female fallow deer was subjected to the necropsy and virological testing, due to a suspected infectious disease in the herd of farmed deer in the Southeastern region of Poland. The animal was found negative for the presence of BVDV, BoHV-1, BTV, and EHDV antibodies and BVDV antigen. The toxicological examination did not reveal any coccidiostats, mycotoxins, rodenticides, carbamate pesticides, and organophosphorus pesticides. The flukes found during postmortem examination were first characterised microscopically as Fascioloides magna and later their identity was confirmed by PCR and sequencing. The autopsy revealed lesions characteristic for F. magna infection, including different size cystic spaces in the liver, filled with brownish mucous fluid and flukes, and black pigment covering the surface of parietal and visceral peritoneum with the highest concentrations localised next to the liver. The changes observed in the liver tissue were typical of liver cirrhosis. The results demonstrated that in Poland, where the cervid farming is developing dynamically, the problem of fascioloidosis is present and may probably exert a significantly negative influence on the productivity of such farms if no antiparasitic treatment is performed.

Reported here is a new analytical multiclass method based on QuEChERS technique, which has proven to be effective in diagnosing fatal poisoning cases in animals. This method has been developed for the determination of analytes in liver samples comprising rodenticides, carbamate and organophosphorus pesticides, coccidiostats and mycotoxins. The procedure entails addition of acetonitrile and sodium acetate to 2 g of homogenized liver sample. The mixture was shaken intensively and centrifuged for phase separation, which was followed by an organic phase transfer into a tube containing sorbents (PSA and C18) and magnesium sulfate, then it was centrifuged, the supernatant was filtered and analyzed by liquid chromatography tandem mass spectrometry. A validation of the procedure was performed. Repeatability variation coefficients <15% have been achieved for most of the analyzed substances. Analytical conditions allowed for a successful separation of variety of poisons with the typical screening detection limit at ≤10 μg/kg levels. The method was used to investigate more than 100 animals poisoning incidents and proved that is useful to be used in animal forensic toxicology cases.

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Introduction: The main problem in poultry farming is the difficulty in producing food of animal origin without using antibacterial agents. Because most antibacterial compounds are dispensed in water, some water supply systems can be contaminated by antibiotics which are then administered to the animals unintentionally. This can lead to unexpected increases in antibiotic residues in food of animal origin. The aim of the present study was to determine whether the constant exposure of chicken broilers to enrofloxacin affects the withdrawal time of a therapeutic doxycycline that is intentionally administered to the chickens. Material and Methods: The concentrations of doxycycline, enrofloxacin, and ciprofloxacin were determined by LC-MS/MS in muscles and liver of the chickens. Results: Doxycycline residue concentrations in the chicken tissues from the group that received trace amounts of enrofloxacin were nearly 50% greater than those of the group that received only doxycycline. Conclusion: These results indicated that constant exposure to enrofloxacin in trace amounts significantly influences the residual doxycycline concentration in chicken tissues.