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The heart rates (HR) and rhythms of 15 healthy donkeys of various ages, both sexes, and various breeds were analyzed throughout 24-hour Holter monitoring. The animals were evaluated at rest in their daily environment without the presence of investigators causing stress, using a three-channel digital Holter recorder. Analysis revealed a maximal HR range from 62.5 to 93.7 beats/min (mean, 72.50 ± 7.51 beats/min), whereas the minimal HR ranged from 29.7 to 42.2 beats/min (mean, 34.90 ± 4.22 beats/min). The daily mean HR was 47.55 ± 3.70 beats/min. The daytime mean HR was 49.39 ± 2.77 beats/min, whereas the night time rate was 46.22 ± 4.38 beats/min. Sinus bradycardia and sinus tachycardia were detected in 7 and 10 of 15 studied donkeys, respectively. Cardiac dysrhythmias due to high vagal tone such as sinoatrial heart block and second-degree atrioventricular heart block were occasionally recorded in 1 and 3 donkeys, respectively. A higher mean HR and fewer cardiac dysrhythmias were observed in donkeys than in horses and ponies at rest. These findings could be justified by differences in the autonomic nervous system tone.  相似文献   
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The aim of the present study was to analyze the effects of drug detection training on behavior and blood neurotransmitter levels in drug detection dogs so as to investigate some variables influencing dog reactivity and responsiveness to training. In all, 20 dogs were sampled out of the Guardia di Finanza canine population. All the subjects were born, reared, housed, and trained in the same facility and followed the same training sessions. Dogs’ behavioral reactivity was scored according to a standardized working dogs test to evaluate natural dog attitudes. Plasma samples were analyzed by the high-performance liquid chromatography method to evaluate adrenaline, noradrenaline, L-3,4-dihydroxyphenylalanine, homovanillic acid (HVA), 3-methoxy-4-hydroxyphenylglycol acid (MHPG), 5-hydroxyindole acetic acid (5-HIAA), and 5-hydroxytryptamine (5-HT) levels. 5-HT and 5-HIAA were also analyzed from platelets. The analysis was carried out considering training, breed, and sex as independent variables. From a behavioral point of view, significant differences were recorded before and after training in “sociability,” “playfulness,” “predatory instinct,” and “aggressiveness” scores. Lower levels of platelet 5-HT and 5-HIAA were found after training. Plasma L-3,4-dihydroxyphenylalanine levels differed between sexes, with males showing higher concentrations. These results underline the importance of complete and objective evaluations protocols of the dogs before, during, and after drugs search training to determine effective and successful selection strategies and training procedures.  相似文献   
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Landscape Ecology - Network-theoretic tools contribute to understanding real-world system dynamics, such as species survival or spread. Network visualization helps illustrate structural...  相似文献   
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Background  

We have recently reported that spontaneous internal desynchronization between the locomotor activity rhythm and the melatonin rhythm may occur in rats (30% of tested animals) when they are maintained in constant dim red light (LLdim) for 60 days. Previous work has also shown that melatonin plays an important role in the modulation of the circadian rhythms of running wheel activity (Rw) and body temperature (Tb). The aim of the present study was to investigate the effect that desynchronization of the melatonin rhythm may have on the coupling and expression of circadian rhythms in Rw and Tb.  相似文献   
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Globe artichoke (Cynara cardunculus L. var. scolymus) plants of a typical landrace (‘Montelupone A’) from the Marche region (Italy) and three commercial cultivars (‘Apollo’, ‘Romanesco C3’, ‘Exploter’) were compared as a detailed analysis of their productive, morphological, qualitative, and nutritional parameters was carried out to characterise their particularities and suitability for the fresh market or the processing industry. Cultivar ‘Apollo’ stands out for its qualitative and agronomic aspects, with ‘Romanesco C3’ showing high flower head yield, as the most important Romanesco cultivar that is widely cultivated in central Italy. ‘Exploter’ shows high productivity and qualitative characteristics. The lower phenol content of ‘Exploter’ indicates its suitability for processing as a fresh cut preparation. The ‘Montelupone A’ landrace is characterised by beneficial nutritional values that indicate its use for fresh consumption and as a source of antioxidant compounds. The ‘Apollo’ and ‘Romanesco C3’ commercial cultivars show higher processing yield due to flower head characteristics. In particular, ‘Apollo’ has an interesting profile according to its technological qualitative and nutritional value. ‘Exploter’ differs in its high yield and suitability for the fresh market. Analysis of the ‘Montelupone A’ landrace confirms its interesting qualitative and nutritional values.  相似文献   
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In primates that are highly sexually dimorphic, males often reach maturity later than females, and young adult males do not show the size, morphology, and coloration of mature males. Here we describe extended male development in a hominin species, Paranthropus robustus. Ranking a large sample of facial remains on the basis of dental wear stages reveals a difference in size and robusticity between young adult and old adult males. Combined with estimates of sexual dimorphism, this pattern suggests that male reproductive strategy focused on monopolizing groups of females, in a manner similar to that of silverback gorillas. However, males appear to have borne a substantial cost in the form of high rates of predation.  相似文献   
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Background  

Daylight saving time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into daylight saving time on the circadian rhythm of activity.  相似文献   
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