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Simple and soft means are needed to manage horse stress. For instance, essential oils such as lavender oil contain active principles that may mitigate stress responses in humans and animals. Here we developed a protocol to test the effects of essential oil on equine stress response. We tested the effect of lavender oil on horse stress. Twenty-eight Welsh horse fillies were divided into two groups: horses treated with a roll-on with 2 mL of vegetable oil (control) and horses treated with 2 mL of 10% lavender essential oil in vegetable oil. Horses were then subjected to a series of stress tests. Heart rates and stress behavioral indicators were monitored during the 30 min of the stress tests. Saliva was collected. Blood from six horses was sampled after lavender essential oil application to follow plasma linalool content and antioxidant efficiency. Results show that stress indicators such as heart rate, alert postures and defecations are lower in lavender oil-treated horses. Lavender essential oil also modified salivary cortisol. Pharmacokinetics of linalool in plasma displayed a peak 20 min after lavender essential oil application, thus confirming the effect of lavender oil. Overall, our findings demonstrate that lavender essential oil reduces the response to stress of horses placed in stressful situations.  相似文献   
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Environmental Chemistry Letters - Most of the catalytic systems for C–C coupling reactions are based on homogeneous catalysts which are normally used only once and do not have a sustainable...  相似文献   
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The concentrations of indicator polychlorinated biphenyls (PCBs No. 28, 52, 101, 138, 153 and 180) and organochlorine pesticides (HCB, p,p′-DDE and p,p′-DDT) in 121 blood serum specimens collected from non-occupationally exposed adults living in contaminated and comparison areas were determined using high-resolution gas chromatography/electron capture detection (HRGC/ECD). The sum of the serum concentrations of the three most abundant PCB congeners (No. 138, 153 and 180) found in participants (N?=?81) living in industrial areas near incinerators, metallurgical and chemical plants (Krompachy, Kosice, Nemecka and Sala) was significantly higher (p?N?=?40). Similarly, significant differences were observed for p,p′-DDE (p?p?U test between groups showed that the difference for HCB was not statistically significant (p?=?0.089). Age was positively correlated with the sum of PCBs (No. 138, 153 and 180), HCB and the sum of p,p′-DDE and p,p′-DDT (p?相似文献   
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The ultimate and proximate causes of natal dispersal have been extensively investigated, but the behaviour of dispersers in relation to social interactions has been largely neglected. Here, we investigated the social organisation of floating individuals during their dispersal by analysing the behaviour of 40 radio-tagged eagle owls Bubo bubo during the wandering and stop phases of dispersal. Unexpectedly, eagle owl floaters mixed with conspecifics independently of their sex, age, phase of dispersal, birthplace, health status and habitat features, showing an ‘underworld’ of interactions characterised by the absence of obvious social organisation or short-term strategies. Non-breeding owls were not transient floaters that occurred at numerous sites for short periods of time but rather had fairly stable home ranges: they attempted to settle as soon as possible within well-defined home ranges. The spatial distribution pattern of floaters and high rates of home range overlap support the prediction that floating individuals are not spatially segregated, challenging the expectation that dominance by size, age and/or health status may determine the exclusive use of some portions of the dispersal area. Finally, (1) the short distances among conspecifics and the extensive home range overlaps allowed us to discard the possibility that neighbouring floaters represent a real cost during dispersal and (2) floater interactions showed a lack of clear mechanisms for avoidance of kin competition among offspring or inbreeding.  相似文献   
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