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71.
In order to evaluate the effects of short transportation on β‐endorphin, adrenocorticotropic hormone (ACTH) and cortisol changes, 12 healthy stallions of Equidae (Equus asinus and Equus caballus) were studied before and after transportation of 50 km. Blood samples were collected 1 week before transportation in basal conditions, immediately before loading and after transportation and unloading, on their arrival at the breeding station. Compared to basal and before values, donkeys showed an increase in circulating ACTH (P < 0.001) and cortisol (P < 0.0005) levels after transportation and higher ACTH (P < 0.01) levels than horses after transportation. A positive and significant correlation (r = 0.885; P < 0.01) between ACTH and cortisol levels after transportation was found. No significant differences were observed for β‐endorphin levels. Compared to basal and before values, horses showed higher cortisol (P < 0.005) levels after transportation and no significant differences were observed for ACTH and β‐endorphin levels in donkeys. Horses facing forward (direction of travel) showed higher (P < 0.01) β‐endorphin levels after transportation than donkeys; horses facing backward (the opposite direction of travel) showed lower (P < 0.05) ACTH levels after transportation. The results indicate that short transportation induces a preferential activation of the hypothalamus‐pituitary‐axis (HPA), with significant release of ACTH and cortisol in donkeys and only of cortisol in horses, suggesting that transportation for donkeys may be more stressful than horses.  相似文献   
72.
Housing conditions and human presence have been shown to have an influence on daily amount of activity in herbivores. Only few studies on the behavior of cats and interactions between cat and human were conducted, and these few works are referred to cats housed in laboratories. At the same way, only few and conflicting reports about the presence of circadian rhythms in cats are present. In view of this incomplete literature, the main aim of our study was to investigate the influence of different housing conditions on daily rhythm of total locomotor activity (TLA) in cats.For this purpose, 10 clinically healthy adult domestic cats were used. They were divided into 2 equal groups living with their owner in their home. Group A lived in 80-100 m2 house and had free daily access to 20-40 m2 garden from 08:00 to 9:00. Group B lived in 200-250 m2 house, had free access to 2000-2500 m2 garden all day, and from 21:00 to 08:00 they were kept outside. Our results showed that in group A, that live in strong symbiosis with owners respect to group B, the amount of activity was higher during the photophase. This supporting the view that domestic cats adapt their lifestyle with their owners. Group B exhibited the highest level of locomotor activity during the scotophase. Moreover, a robust daily rhythmicity of TLA was observed in group B; on the contrary, in group A, TLA showed no daily rhythmicity. Our findings underline the high influence of human presence and care on the amount of activity and daily rhythm in cats.  相似文献   
73.
Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile.  相似文献   
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75.
In the sport field, non‐esterified fatty acids (NEFA) are important for the physical performance during the aerobic exercise of short intensity and long duration. In man, rat, goat and in the sedentary horse studies on the chronometabolism showed the presence of a circadian rhythm of the plasmatic concentration of NEFA while data for the athletic horse are lacking. To define a chronogram helpful for a specific planning and the differentiation of the training programmme in the athletic horse, the circadian pattern of some fatty acids (NEFA, palmitic, stearic, oleic, linoleic and linolenic acids) was studied in five Sella Italiana horses. These horses trained following a daily model of activity consisting of walk, trot, gallop and jump of obstacles of different heights. Blood samples were collected from the jugular vein every 4 h, starting at 08:00 hours, for 2 days to assess the concentrations of total NEFA (by spectrophotometry), palmitic, stearic, oleic, linoleic and linolenic acids (by gas chromatography). anova for repeated measures showed a statistical significant effect of the time of the day in NEFA, oleic and linolenic acids. The application of the periodic model showed the periodic pattern of NEFA, oleic, linoleic and linolenic acids. Acrophases were in the afternoon for all parameters. The results obtained showed a different trend of the circadian pattern of the studied parameters in the athletic horse than in the sedentary one because the physical activity and the post‐prandial metabolism acted as zeitgebers.  相似文献   
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