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Angiostrongylus vasorum, French heartworm, is a metastrongloid parasite found in the pulmonary arteries and right ventricle of wild and domestic canids and various other animals. The natural definitive hosts are species of foxes. The geographic distribution of the parasite includes various countries of Europe, Africa, South America, and North America. Angiostrongylosis is considered an emerging disease in dogs in Europe. In North America, autochthonous A. vasorum infection occurs only in the Canadian province of Newfoundland-Labrador. Computer modeling suggests there is a high probability that A. vasorum will spread to other parts of North America and will likely become endemic in the eastern half of the continent and in the states and provinces along the western coast. Animals acquire infection by the ingestion of gastropod or frog intermediate hosts that carry the infective 3rd-stage larvae. Frogs can also serve as paratenic hosts. Definitive antemortem diagnosis is by detection of L(1) in feces, sputum, or bronchoalveolar lavage samples. Baermann fecal examination is the most reliable method for fecal detection. However, false negative results can occur due to the typical erratic/sporadic fecal larval shedding pattern of A. vasorum. Recently, promising new methods for A. vasorum infection diagnosis have been reported involving polymerase chain reaction of blood and fecal samples and a sandwich ELISA for detection of circulating worm excretory/secretory antigen. Current treatment options include moxidectin, milbemycin oxime, and fenbendazole.  相似文献   
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Objective: To review the use of cardiac troponins as biomarkers for myocardial injury in human and veterinary medicine. Data sources: Data sources included scientific reviews and original research publications. Human data synthesis: Cardiac troponins have been extensively studied in human medicine. Finding an elevated cardiac troponin level carries important diagnostic and prognostic information for humans with cardiovascular disease. Troponin assays are used primarily to diagnose acute myocardial infarction in patients with ischemic symptoms such as chest pain. However, elevated blood levels may be found with any cause of myocardial injury. Veterinary data synthesis: Several studies have shown that cardiac troponins are sensitive and specific for myocardial damage in veterinary patients and may have utility in diagnosis and prognosis for certain disease states. Human assays may be used in most animals due to significant homology in the troponin proteins between species. Conclusions: Cardiac troponins are sensitive and specific markers of myocardial injury although they do not give any information regarding the mechanism of injury. They have redefined how acute myocardial infarction is diagnosed in humans. Their use in the clinical management of veterinary patients is limited at this time. Further prospective studies are warranted.  相似文献   
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We investigated the physiological effects on goats of transportation for one hour in a small truck. We also investigated food and water consumption after transportation. Eight adult goats (four castrated males and four ovariectomized females) were used. Plasma levels of cortisol, glucose and free fatty acids increased significantly within 15 min of the start of transportation, and these higher levels were maintained throughout transportation. These results indicate that transportation in a small truck activates the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system in goats. Despite activation of the sympathetic nervous system, heart rate (HR) in subjected animals during transportation did not differ from during the control animals, which were housed in their usual pen. However, after the transportation had ended and the goats started to eat fodder, HR increased significantly. There was no difference in the amount of food consumption between the control and transported goats. Water consumption in the first three hours after transportation was significantly lower in the transported goats than in the controls for the equivalent period. In the subsequent three hours, however, the transported goats consumed more water than the controls. Consequently, the total water consumption of the transported goats did not differ from that of the controls during the six hours after transportation. In conclusion, short-term transportation with a small vehicle activated the HPA axis and the sympathetic nervous system in goats. HR was not increased during transportation, but after the transportation had ended HR in transported goats was higher than that in control goats. After transportation, goats had consumed the same amount of food as control goats, but water consumption during three hours after the transportation was lower than that of control goats.  相似文献   
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张泽樘  詹勋  吴银宝  罗庆斌 《中国家禽》2012,34(3):18-20,24
选择华南农业大学增城正大肉鸡发展中心的肉种鸡舍为研究对象,在夏季分别对该鸡舍的气温、气湿、风速等温热环境因子进行测定,用以评价该鸡舍采用的湿帘通风系统对鸡舍内温热环境因子的调节效果。结果表明,夏季采用湿帘通风系统的鸡舍平均舍温比舍外气温低3~4℃,相对湿度保持在80%左右;夏季采用湿帘通风系统可以有效地降低舍温,主要表现为前端降温效果明显,后部降温效果有所下降;中间比两侧的降温效果好。表明夏季采用湿帘通风系统对种鸡舍内的温热环境控制较好。  相似文献   
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试验旨在对鲁西黄牛心型α肌动蛋白的进化及表达进行研究,为研究该基因的功能提供依据。试验采用生物信息学方法对心型α肌动蛋白的进化进行了分析,利用Western blotting和免疫荧光的方法分析了牛心型α肌动蛋白的表达模式。结果显示,心型α肌动蛋白除在鲁西黄牛心脏组织中有强表达外,在骨骼肌中也检测到该蛋白的表达。推测心型α肌动蛋白除在成体鲁西黄牛的心脏发育过程中起作用外,在骨骼肌发育过程中也起作用。  相似文献   
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The aim of this study was to determine whether autonomic nervous activity of a rider with no disability was altered by one practical and applicable horse trekking (HT) exercise. Changes in autonomic nervous activity were analyzed by heart rate variability (HRV). Twenty‐three participants with no disability rode horses along a predetermined HT course at trotting and walking for 60 min. HRV was sampled at 60 min before and immediately, following 60 min, and 120 min after HT. As a control, the same measurements were performed for 22 age‐matched participants during their rest. Only in the HT group, the value of normalized unit in high frequency component (HF nu), an index of parasympathetic nervous activity, was higher at 120 min after treatment than before HT (P < 0.05). The low / high frequency ratio (LF / HF), believed to reflect sympathetic nervous activity, was lower in the HT group than those in the control group at 60 min (P < 0.05) and 120 min after treatment (P < 0.01). These findings suggest that a single HT shifted the autonomic nervous balance of a rider toward parasympathetic dominance. The results obtained by the present study could accelerate the use of horses for human health.  相似文献   
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