The use of thyreostats as veterinary drugs is banned in the European Union since 1981 because of their carcinogenic and teratogenic properties. Controlling their illegal use in breeding animals is quite difficult because of their low molecular weight, high polarity and the presence of tautomeric forms. To harmonise the performance of analytical methods, the recommended concentration for thyreostats such as thiouracil, methylthiouracil, propylthiouracil and tapazole established by the Community Reference Laboratory in 2007 is 10 ng g(-1). The majority of the currently available analytical methods require a time-consuming derivatisation step and/or an SPE clean-up step. In this study, a rapid confirmatory method for the determination of six thyreostatic drugs - thiouracil, methylthiouracil, propylthiouracil, phenylthiouracil, tapazole and 2-mercaptobenzoimidazole - in thyroid and muscle at recommended concentration is presented. Quick sample extraction has been achieved by QuEChERS with ethyl acetate without further clean-up or derivatisation steps. Analysis has been carried out by using UPLC-ESI-MS/MS. Performance characteristics of the method have been determined in agreement with Commission Decision 2002/657/EC requirements for confirmatory methods and calculated decision limits (CCα) are below the recommended concentration (10 ng g(-1)).
During oestrus, fattening female pigs are more prone to lameness, fractures and wounds due to mounting and agonistic behaviours of penmates. This study assessed the effect of sexual maturity on the behaviour and welfare of heavy female pigs slaughtered at 36 weeks of age (180±10 kg) for dry-cured ham production. An immunocastrated control group was used for comparison. In all, 56 15-week-old female pigs, individually identifiable by back tattoos were equally distributed among four pens. All animals from two pens were subject to a three-dose immunocastration schedule at 16, 20 and 32 weeks of age. Skin lesions and behaviours were assessed at 18, 23, 28, 33 and 36 weeks of age. A blood sample was collected at 20, 24, 28 and 32 weeks of age for assessing health/stress parameters and GnRH antibodies. At slaughter, ovaries were weighed, measured and histologically examined; stomachs, carcasses and lungs were scored for lesions and a further blood sample was taken. Immunocastrated pigs did not significantly differ from controls in growth rate, feed efficiency and slaughter performances (lung score, gastric score, backfat thickness). However, they showed a lower frequency of aggressive interactions at 33 and 36 weeks, lower front lesions at 28 weeks, but higher at 30 weeks; a lower haptoglobin level at 28 weeks, a lower level of cortisol and back lesions at slaughter (36 weeks). These findings suggest a low, yet not negligible, impact of sexual maturity on the welfare of heavy female pigs.
The availability of sensitive analytical methods to detect per- and polyfluoroalkyl substances (PFASs) in food of animal origin is fundamental for monitoring programs to collect data useful for improving risk assessment strategies. The present study aimed to develop and validate a fast and sensitive method for determining short and long-chain PFASs in meat (bovine, fish, and swine muscle), bovine liver, hen eggs, and cow’s milk to be easily applicable in routine analysis of food. A QuEChERS extraction and clean-up method in combination with liquid chromatography coupled to mass spectrometry (LC-MSMS) were used. The method resulted in good linearity (Pearson’s R > 0.99), low limits of detection (7.78–16.35 ng/kg, 8.26–34.01 ng/kg, 6.70–33.65 ng/kg, and 5.92–19.07 ng/kg for milk, liver, egg, and muscle, respectively), and appropriate limits of quantification (50 ng/kg for all compounds except for GenX and C6O4, where the limits of quantification were 100 ng/kg). Trueness and precision for all the tested levels met the acceptability criteria of 80–120% and ≤20%, respectively, regardless of the analyzed matrix. As to measurement uncertainty, it was <50% for all compound/matrix combinations. These results demonstrate the selectivity and sensitivity of the method for simultaneous trace detection and quantification of 14 PFASs in foods of animal origin, verified through the analysis of 63 food samples.
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