Residues of an anthelmintic veterinary drug (closantel) detected in red foxes (Vulpes vulpes) in Scotland.

The contamination of the environment by some veterinary medicines and their impact on wild animals is of increasing concern. However, there is a lack of information about their residues in wildlife. The sentinel animals most commonly used for monitoring the level of environmental contamination are birds of prey, and information on other carnivores and scavengers scarce. This study examined the livers from 118 foxes for residues of a range of 18 veterinary medicines (16 anthelmintic agents and 2 metabolites) used on farm livestock. The samples were collected from foxes, primarily in Scotland, shot during legal pest control activities conducted between 2014 and 2019. Closantel residues were detected in 18 samples, and the concentrations found ranged from 6.5 µgkg-1 to 1383 µgkg-1. No other compounds were found in significant quantities. The results show a surprising frequency and level of closantel contamination, raising concerns about both the route of contamination and the potential impacts on wild animals and the environment, such as the potential for significant wildlife contamination to contribute to the development of closantel-resistant parasites. The results also suggest that red fox (Vulpes vulpes) could be a useful sentinel species for detecting and monitoring some veterinary medicine residues in the environment.

White-Tailed Eagles' (Haliaeetus albicilla) Exposure to Anticoagulant Rodenticides and Causes of Poisoning in Poland (2018-2020).

The white-tailed eagle (Haliaeetus albicilla) is strictly protected in Poland due to its threat of extinction. This study's main goal was to assess their exposure to indirect poisoning by anticoagulant rodenticides (AR). This study presents the investigation results of 40 white-tailed eagles' suspected poisoning cases in the years 2018-2020 in Poland. In all tested liver samples, using a liquid chromatography-mass spectrometry method, at least one of the AR (bromadiolone, brodifacoum, difenacoum, flocoumafen) was detected and confirmed. The other tested AR compounds (chlorophacinone, coumachlor, coumatetralyl, difethialone, diphacinone, warfarin) were not detected. The mean concentration of the sum of rodenticides was 174.4 µg/kg (from 2.5 to 1225.0 µg/kg). In 20 cases, the sum concentration was above 100 µg/kg and in 10 cases it was above 200 µg/kg. Interpretation of cases of AR poisonings should take into account their concentration in the liver, anatomopathological lesions, circumstances of death/finding of the animal, and elimination of other possible causes of poisoning. Based on this study, AR was the direct cause of death in 10% of incidents. Extensive use of rodenticides generates a high risk of poisonings of white-tailed eagles in Poland.

A Preliminary Study of the Poultry Body Weight Effect of Carvacrol in Litter and Of Carvacrol Residue in Organ Tissue of Exposed Chickens.

Introduction: Carvacrol is an essential oil extracted from oregano which can be used as a natural additive in poultry litter and could have a positive impact not only on production rates but also on the quality of poultry meat. The aim of this study was to evaluate the effect of the addition of carvacrol to litter on weight gain and the occurrence of residues in chicken tissues. Material and Methods: One-day-old Ross 308 chicks were used for the study and were randomly divided into two experimental groups. For 42 days, one group was kept in a room with litter enriched with carvacrol and the second group was kept in a room with litter without carvacrol. After 42 days, the birds were sacrificed and necropsied. Carvacrol content was determined in homogenised organ tissue samples by liquid chromatography-mass spectrometry. Results: Weekly weighing results showed that exposure to carvacrol in litter had no impact on chicken body weight. The analysis of plasma, muscle, liver and lung tissue after 42 days' exposure clearly indicated that there were residues of carvacrol in the analysed matrices. Conclusion: Exposure of chickens to carvacrol left residues but did not affect body weight.

The Markers of Stress in Swine Oral Fluid.

INTRODUCTION: The study measured the hormonal and protein markers of acute stress, those of oxidative stress and total antioxidant capacity (TAC) in swine oral fluid, determined which of these parameters would be the most appropriate for future livestock welfare assessment and established the time when the samples should be taken. MATERIAL AND METHODS: Stress was induced in 7 out of 14 castrated six-week-old Danbred×Duroc pigs by immobilisation on a nasal snare at 8 a.m., 1 p.m., and 6 p.m. and samples were taken both directly after the stressor was applied and 30 min later. The remaining pigs were the control group, which were not immobilised; their samples were taken at the same times. The concentrations of hormones and malondialdehyde (MDA) were measured using liquid chromatography with tandem mass spectrometry, while those of alpha-amylase and TAC were measured using spectrophotometry. RESULTS: The levels of cortisol and cortisone increased with statistical significance immediately after the acute stress response and 30 min later. A cut-off value set at 0.25 ng/mL cortisol concentration was capable of distinguishing between the stressed and control groups with 100% accuracy in evening samples and 95% accuracy overall. Prednisolone was not present, and the levels of testosterone and corticosterone were low and not distinctive. Alpha-amylase became significantly more concentrated during stress induction and 30 min later. The TAC and MDA levels rose after the stress but without statistical significance. CONCLUSION: The most suitable markers of acute stress were cortisol, cortisone and alpha-amylase. Oral fluid is a reliable material for monitoring the level of pigs' stress and should be collected in the evening.

QuEChERS and HPLC-MS/MS Combination for the Determination of Chloramphenicol in Twenty Two Different Matrices.

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 (CCß) 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.

Ingestion of bedding material as a cause of acute copper sulfate poisoning in turkey poults.

The article reports a case of acute copper sulfate (CuSO4) poisoning in 2-day-old turkeys. The first incidences were noticed 2 h after placing the animals in the poultry house, where turkeys were provided with wood shaving bedding. Post-mortem examination showed wood shavings present in gastric and intestinal contents and numerous lesions in the alimentary tract: dark green color of the koilin lining, and surface erosions, deep ulceration, and severe congestion of the gizzard. The copper (Cu) concentration in samples of the liver, kidney, heart, gizzard content, gizzard muscle, gizzard lining, and wood shavings from the bedding was determined. Our results showed that the level of Cu in the livers of affected birds was more than sevenfold higher than the recommended value and the Cu content in bedding material was above the value considered to be toxic to turkeys. Our investigation identified the bedding disinfected using a CuSO4 solution as a possible cause of turkey fatalities.

Comparison between endometrial protein profile in Holstein-Friesian heifers and female prepubertal calves.

The protein profile of each tissue depends on the expression of genes that are regulated, among others, by sex steroids. Comparing the profiles of sexually immature and mature females should therefore define markers of age-related changes. The aim of this study is to compare the pattern of proteins in the endometrium of heifers and pre-pubertal female calves by using difference in gel electrophoresis (DIGE), and to identify the presence and amount of similar or significantly different proteins. Endometrial samples were collected in slaughterhouse from heifers aged between 14-27 months (n = 6; sexually mature) and calves between 0.5-2 months (n = 6; sexually immature). All animals were healthy, Holstein-Friesian bred animals. Samples were subjected to fluorescent staining and 2D electrophoresis. Out of more than 900 spots detected in the endometrium of heifers, 73% were similar to calves. Selected spots were identified. Angiopoietin-2 and dynamin-like protein were detected only in heifers. These proteins are involved in angiogenesis and cell membrane remodelling, respectively. Aldose reductase, and phospholipase, which are important for prostaglandin metabolism, were present in different amounts in both sources. These results help to further understand the mechanism of steroid hormone action and look for markers of bovine endometrium status. Moreover, fluorescent staining appeared to be an useful tool when comparing 2 samples from different sources.

New Method of Analysis of Nitrofurans and Nitrofuran Metabolites in Different Biological Matrices Using UHPLC-MS/MS.

INTRODUCTION: The major difficulty in analysis of nitrofurans in feed, feed water, and food of animal origin is that nitrofurans have low molecular weights and fast metabolism. The principal goal of this study was to prepare a procedure for the determination of nitrofurans and their metabolites by a single method in different types of feed, feed water, and food of animal origin. MATERIAL AND METHODS: Two-gram samples were subjected to hydrolysis and derivatisation processes by addition of hydrochloric acid and 2-nitrobenzaldehyde. After incubation the sample was purified by solid phase extraction technique. Nitrofurans were analysed using ultra-high-pressure liquid chromatography-MS/MS (UHPLC-MS/MS). RESULTS: The results of validation fulfil the requirement of the confirmatory criteria according to the European Commission Decision 2002/657/EC regarding apparent recoveries (88.9%-107.3%), repeatability (2.9%-9.4%) and within-laboratory reproducibility (4.4%-10.7%). CONCLUSION: The method can be successfully applied to monitor nitrofurans and their metabolites in different matrices.

The influence of age and gender on antioxidant enzyme activities in humans and laboratory animals.

Antioxidative/oxidative balance is one of the important factors for homeostasis. Antioxidative systems which protect from peroxidative damage are supposed to be under the influence of steroid hormones. The implications of this influence are age and gender as well as tissue dependent alterations in antioxidative enzyme activities. Apart from hormonal influence, antioxidative enzymes require the presence of microelements in their active centers as well as concerted action of non enzymatic antioxidants which support enzymes in their scavenging action. The aim of this review is to analyze and compare existing knowledge about the changes in activity of antioxidant enzymes in human and animal females and males of different age. Evidence as regards participation of oxidative stress in senescence are specific diseases which, to some extent, are gender dependent and appear more frequently in males or females. Several experiments in laboratory animals revealed that changes in enzyme activities are reflected in histopathological pictures of cells. The alterations observed during perimenopausal period provide with additional evidence of the participation of steroid hormones in the regulation of antioxidative system activity. Moreover, estrogens themselves exhibit antioxidative activity which is receptor independent. In conclusion, apart from genetic-related influences, also diet and style of life may have an impact on the antioxidative system which requires appropriate supplementation in microelements and vitamins for its effective function of scavenging excess of free radicals.