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Forty-six racehorses with a history of poor performance underwent endoscopic evaluation of laryngeal and pharyngeal function while exercising on a high-speed treadmill. This evaluation allowed the definitive diagnosis of intermittent or continual upper respiratory tract obstruction as a cause of poor performance, as well as the documentation of the dynamic functional anatomy of the obstruction. Ten of the horses (22%) were determined to have a functional abnormality of the upper respiratory tract. These abnormalities included epiglottic entrapment (1 horse), persistent dorsal displacement of the soft palate during exercise (4 horses), and left laryngeal hemiplegia (5 horses). Thirty-two horses were observed to have signs of left laryngeal hemiparesis (asynchronous arytenoid movement) at rest that did not impair full laryngeal abduction during strenuous exercise.  相似文献   
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Dactylis glomerata L. is a widespread perennial grass species, which has been reported to be adapted to shaded conditions. Its populations thrive in a variety of environments. However, little information is available concerning the comparative response of its natural populations from contrasting environments under the reduced light intensity conditions that exist in silvopastoral systems. The objective of the present study was to estimate the comparative ability of three populations of D. glomerata from northern, central and southern Greece to grow under full sun, 60 % shade and 90 % shade in terms of their growth characteristics, phenotypic plasticity, dry matter production and nutritive value. Shade reduced tillering and dry matter production, increased tiller height and modified leaf characteristics. Under shade fewer leaves were grown simultaneously on the same tiller, but these were longer and thinner compared to full sun. Differentiation in response to shade among the populations examined of D. glomerata was observed mainly for leaf characteristics. The population from Pertouli (central Greece) responded better, particularly to moderate shade as it had a higher leaf area, longer leaf and higher dry matter production, compared to the others. Evidence for adaptive phenotypic plasticity to moderate shade was suggested only for this population. Additionally, Pertouli had higher nutritive value compared to Taxiarchis (northern Greece) and Crete (southern Greece) under shade. The divergent responses of natural populations of D. glomerata could justify breeding germplasm with enhanced shade tolerance.  相似文献   
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Journal of Pest Science - Birds provide important ecosystem services in many ecosystems, including important pest control effects on productive systems. The typically low bird diversity observed in...  相似文献   
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