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D R Nelson W A Wolff D J Blodgett B Luecke R W Ely J F Zachary 《Journal of the American Veterinary Medical Association》1984,184(12):1480-1485
Zinc deficiency was diagnosed in 2 flocks of sheep and a herd of goats. Alopecia and eating of wool were observed. Skin lesions were hyperkeratosis and parakeratosis. Abnormal hoof growth and a closed stance with arched back and bowed hindlimbs were seen. Anorexia, depression, and foot soreness diminished quickly after zinc supplementation. Skin lesions healed and hair and wool growth resumed. A cause for the deficiency could not be established. 相似文献
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R D Welsh R W Ely R J Holland 《Journal of the American Veterinary Medical Association》1992,201(1):142-144
An epizootic attributable to Yersinia pseudotuberculosis infection was confirmed in captive ruminants in a wildlife park by microbiologic and histologic findings. An epornitic of Y pseudotuberculosis infection was identified at the same period in a vicinity near the ruminant deaths. Yersinia pseudotuberculosis can infect human beings and cause acute enteritis and mesenteric lymphadenitis. People in contact with infected animals should use extreme caution and use good sanitary precautions to preclude transmission of this agent. 相似文献
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There is a growing need for both science and practice domains to collaboratively and systematically seek knowledge-based strategies for sustainable development.In recent years,transdisciplinary research has emerged as a new approach that enables joint problem solving among scientists and stakeholders in various fields. In this paper,we aim to introduce transdisciplinary research for supporting the integration of the concept of ecosystem services into land and water management in the Tarim River Basin,Xinjiang,Northwest China.While a large number of ecosystem service studies have helped to raise the awareness for the value of nature in China,a number of challenges remain,including an improved understanding of the relationships between ecosystem structure, functions and services,and the interaction of the various ecosystem services.A meaningful valuation of ecosystem services also requires the consideration of their strong spatial heterogeneity.In addition,ways to introduce the concept of ecosystem services into decision-making in China need to be explored.Thus,successful integration of the concept of ecosystem services into actual land and water management requires a broad knowledge base that only a number of scientific disciplines and stakeholders can provide jointly,via a transdisciplinary research process.We regard transdisciplinary research as a recursive process to support adaptive management that includes joint knowledge generation and integration among scientists and stakeholders.System,target,and transformation knowledge are generated and integrated during the process of(1)problem(re)definition,(2)problem analysis and strategy development,and(3)evaluation of the impact of the derived strategy.Methods to support transdisciplinary research comprise participatory modelling(actor-based modelling and Bayesian Networks modelling)and participatory scenario development.Actor-based modelling is a semi-quantitative method that is based on the analysis of problem perspectives of individual stakeholders as depicted in perception graphs.With Bayesian Networks,complex problem fields are modelled probabilistically in a simplified manner,using both quantitative data and qualitative expert judgments.These participatory methods serve to integrate diverse scientific and stakeholder knowledge and to support the generation of actually implementable management strategies for sustainable development.For the purpose of integrating ecosystem services in land and water management in the Tarim River Basin through transdisciplinary research,collaboration among scientists and institutional stakeholders from different sectors including water,agriculture,forestry,and nature conservation is required.The challenge is to adapt methods of transdisciplinary research to socio-cultural conditions in China,particularly regarding ways of communication and decision-making. 相似文献
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LILJA STEFANSDOTTIR JÓN SOLMUNDSSON GUÐRÚN MARTEINSDOTTIR KRISTJÁN KRISTINSSON JÓNAS PÁLL JONASSON 《Fisheries Oceanography》2010,19(1):42-62
Elevated ocean temperatures have been predicted to lead to a poleward shift in the latitudinal distribution ranges of fish species. Different responses of fish species to increased temperatures might lead to changes in assemblage structure and local species richness. In this study, the assemblage structure and diversity of groundfish in Icelandic waters were examined using data from a standardized groundfish survey conducted annually in 1996–2007. We used hierarchical cluster analysis to define assemblages in two time periods and canonical correspondence analysis to explore the relationships between the assemblages and temperature, depth, latitude, longitude and year. We further used two estimates of diversity, species richness and the Shannon index. Four major species assemblages were identified. Assemblages in the hydrographically stable deep waters north of the country were consistent during the study, while assemblage structure in the more variable shallow waters underwent some changes. For this period of generally increasing sea temperature, the canonical correspondence analysis also revealed a shift towards species representative of warmer temperatures. Diversity was shown to be highly variable both temporally and spatially, and also to vary with depth and temperature. Species richness increased with temperature and time southwest of the country, but decreased northeast of the country. The different trends detected between the northern and southern areas illustrate the importance of performing analyses at the most appropriate scale. 相似文献
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Bacterial associations with plant roots are thought to contribute to the success of phytoremediation. We tested the effect of addition of a polycyclic aromatic hydrocarbon contaminated soil on the structure of the rhizosphere microbial communities of wheat (Triticum aestivum), lettuce (Lactuca sativa var. Tango), zucchini (Cucurbita pepo spp. pepo var. Black Beauty), and pumpkin (C. pepo spp. pepo var. Howden) 16S rDNA terminal restriction fragment length polymorphism (T-RFLP) profiles of rhizosphere microbial communities from different soil/plant combinations were compared with a pairwise Pearson correlation coefficient. Rhizosphere microbial communities of zucchini and pumpkin grown in the media amended with highest degree of contaminated soil clustered separately, whereas communities of these plants grown in unamended or amended with lower concentrations of contaminated soil, grouped in a second cluster. Lettuce communities grouped similarly to cucurbits communities, whereas wheat communities did not display an obvious clustering. The variability of 16S rDNA T-RFLP profiles among the different plant/soil treatments were mostly due to the difference in relative abundance rather than presence/absence of T-RFLP fragments. Our results suggest that in highly contaminated soils, the rhizosphere microbial community structure is governed more by the degree of contamination rather than the plant host type. 相似文献
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