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The objective of this study was to investigate the influence of orally administered biotin on the healing of uncomplicated sole ulcers in dairy cattle. In a double-blind controlled study, 24 dairy cows with a mild, uncomplicated sole ulcer on a lateral hind claw were given either 40 mg biotin per day or a placebo feed over a period of 50 days. An orthopaedic shoe was fitted to the medial claw of the affected foot. The healing process was assessed clinically and by histological examination of horn samples. In the biotin-treated animals, the newly formed epidermis covering the sole ulcers was found to be of significantly better histological quality after 50 days than at the start of the study. The significant improvement in histological horn quality found in the biotin-treated animals suggests that biotin exerts a positive influence on the healing of sole ulcers, however the study period of 50 days appears to have been too short to permit macroscopic detection of the improvement in horn quality.  相似文献   
23.
Laboratory experiments were conducted to test the effect of various concentrations of Trifluralin on certain fungi. The ectotrophic mycorrhizal fungi tested were: Amanita citrina Schaefer, Tricholoma pessundatum (Fr.) Quel., and Tricholoma saponaceum (Fr.) Qtiel. All exhibited sensitivity to Trifluralin concentrations. The consequence of such fungitoxicity was discussed.  相似文献   
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Pot experiments were performed to investigate the effects of Tritluralin on the mycorrhizal symbiosis of conifer seedlings. Infected forcst soils and potting mixturcs were mixed, pottcd and treated with Trifluralin at levels of 0.2 and 0.4ml/m2 Seeds of Pinus sylvestris L. and Picea abies (L.) Karst. were sown in the pots. The concentrations tested, though recommended by the manufacturer produced phytotoxicity. The seedling growth in general and that of the rootsystem and laceral roots in particular, were severely inhibited. Mycorrhizal development in the seedlings was consequently adversely affected.  相似文献   
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20 trials of materials used in buildings have been offered to dermestid larvae to bore in for pupations. Two different types of damage are described. Eight different test substances have been more or less damaged by the larvae.  相似文献   
27.

Silvopastoral systems integrate the complexity of forestry and forage-livestock management in an economically and ecologically sustainable way. However, these systems have undergone intensive pressure over the past decades caused by changes in land uses, as well as, in local socioeconomic priorities that suppressed traditional practices such as livestock grazing. These changes have caused land cover spatiotemporal diversifications whose effects were investigated in a traditional oak silvopastoral system at western Greece. In order to investigate the effect of human activities over the study area, the spatiotemporal land cover changes in conjunction with human and animal population changes and the environmental factors altitude, soil depth, inclination and rock type were analyzed. Also, forest-crown density changes were examined as a complimentary factor for the investigation of human intervention in the study area. Data about land-cover changes were derived from aerial orthorectified photographs of years 1945 and 2008, complimented by maps of environmental factors. Data digitization was implemented by the use of ArcGis. Based on the data analysis it derives that land cover changes are mainly attributed to direct human intervention. Environmental factors affect the ecosystem in two ways; first by affecting the location, type and intensity of human activities in the area, for example, soil depth determines where land is more productive and so predetermines the location, type and intensity of agricultural activities. Secondly, in the areas without or with minimal human intervention, environmental factors affect directly the land cover in conjunction with natural species necessities and their antagonistic capabilities.

  相似文献   
28.
The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive.  相似文献   
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Eddy covariance (EC) systems are being used to assess the accuracy of remote sensing methods in mapping surface sensible and latent heat fluxes and evapotranspiration (ET) from local to regional scales, and in crop coefficient development. Therefore, the objective was to evaluate the accuracy of EC systems in measuring sensible heat (H) and latent heat (LE) fluxes. For this purpose, two EC systems were installed near large monolithic weighing lysimeters, on irrigated cotton fields in the Texas High Plains, during the months of June and July 2008. Sensible and latent heat fluxes were underestimated with an average error of about 30%. Most of the errors were from nocturnal measurements. Energy balance (EB) closure was 73.2–78.0% for daytime fluxes. Thus, daylight fluxes were adjusted for lack of EB closure using the Bowen ratio/preservation of energy principle, which improved the resulting EC heat flux agreement with lysimetric values. Further adjustments to EC-based ET included nighttime ET (composite) incorporation, and the use of ‘heat flux source area’ (footprint) functions to compensate ET when the footprint expanded beyond the crop field boundary. As a result, ET values remarkably matched lysimetric ET values, with a ‘mean bias error ± root mean square error’ of −0.03 ± 0.5 mm day−1 (or −0.6 ± 10.2%).  相似文献   
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