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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.
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed for the determination of melamine in feed samples. After a preliminary dissolution in acetonitryle and 0.05 M phosphate buffer, the obtained extract was sonicated for 10 min and supernatant was collected. The supernatant was cleaned up on SCX solid phase extraction cartridges. Melamine was determined, using electrospray ionisation in the positive mode, followed by separation on the carbon column Thermo Hypercarb. The whole procedure was validated for the identification and determination purposes. Feed samples were spiked with melamine solution at levels corresponding to 0.5-1.0-2.5-10.0 mg/kg. At the studied levels, trueness ranged between 78.0% and 82.3% and within-laboratory reproducibility expressed as a relative standard deviation was lower than 15%. The limit of detection was estimated at the level of 0.58 mg and limit of quantitation was 0.65 mg/kg.
A multiresidue method for determination and quantification of Fusarium mycotoxins: deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, and metabolite of Aspergillus and Penicillium species - ochratoxin A in feeds was described. The method was based on the simultaneous extraction of selected mycotoxins from matrix, followed by liquid chromatography coupled with tandem mass spectrometry using a hybrid triple quadmpole - linear ion trap mass spectrometer with the multiple reaction monitoring in both positive- and negative-ion modes. The method was validated in accordance with the Commision Decision 2002/657/EC requirements. The mean recoveries of mycotoxins from spiked feed samples ranged from 74.6% to 113.9%, whereas limit of detection and quantification ranged from 0.72 to 12.4 µg/kg and 1.86 to 31.7 µg/kg, respectively.
A liquid chromatographic method coupled with UV-Vis and fluorescence detectors for the determination of azaperone, carazolol, and chlorpromazine residues in urine has been described. Analytes were isolated from biological samples with acetonitrvle. The obtained extracts were applied to solid phase extraction Strata X-C 33 µn Polimeric Strong Cation columns. The analytes were eluted with alkalised acetonitrvle. The whole procedure was validated according to European Decision 657/2002/EC. The detection limits were established at the level 2 µg/L for Carazolol and 5 µg/L for azaperone and chlorpromazine. Detection capabilities for carazolol, azaperone, and chlorpromazine were 8.62, 18.9, and 6.53 µg/L, respectively. Recoveries were above 90%.
An in-house reference material of chloramphenicol (CAP) in pigs muscle was prepared from the chloramphenicol treated animals. The incurred muscle material was diluted by mixing with blank muscle sample. The concentration of CAP at the level 0.33 µg kg⁻¹ was reached. For the homogeneity study, 10 random samples were analysed and the results were interpreted by Cochran's test and the sufficient homogeneity test. Additionally, the samples were tested for their stability according to the following scheme: 1, 7, 14, 28, 56, 84, and 112 d. It was confirmed that an appropriate homogeneity and stability of the produced in-house reference material was obtained.
A liquid chromatographic method coupled with UV- Vis and photodiode-array detection for the determination of nitrofuran residues: nitrofurazone, nitrofurantoin, furazolidone, and furaltadone in water was developed and validated. Confirmation of the identity of nitrofurans was performed by liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization interface. The nitrofurans were isolated from water by solid-phase extraction and complete separation was obtained using a C18 analytical column and the mobile phase consisting of acetonitrile and 0.01 M sodium acetate buffer pH=6.0 (250:750, v/v), with the detection at λ=376 nm. Average recoveries for the compounds ranged from 63% to 90%. The results of the validation show that the method can be successfully used for the official control of nitrofurans in water.
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