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Simon J. More Angus R. Cameron Matthias Greiner Richard S. Clifton-Hadley Sandra Correia Rodeia Douwe Bakker Mo D. Salman J. Michael Sharp Fabrizio De Massis Alicia Aranaz M. Beatrice Boniotti Alessandra Gaffuri Per Have Didier Verloo Michael Woodford Martin Wierup 《Preventive veterinary medicine》2009,90(3-4):254-267
Within the European Union (EU), detailed legislation has been developed for cattle, but not deer, to minimise disease risks associated with trade in animals and animal products. This legislation is expressed as input-based standards, providing a detailed outline of the activity required (for example, testing of animals and application of defined control measures), on the expectation that an adequate output (for example, confidence in freedom) will be achieved. Input-based standards are at odds with the increasing shift towards output-based standards, particularly in OIE rules governing international trade. In this paper, we define output-based standards to achieve and maintain freedom from tuberculosis (TB) in farmed deer, with reference to EU member states. After considering the probability of freedom achieved for cattle under existing EU legislation, we defined a ‘free farmed deer holding’ as one with a probability of freedom from infection of at least 99%. We then developed an epidemiological model of TB surveillance systems for deer holdings, incorporating different surveillance strategies, including combinations of diagnostic tests, and a variety of different scenarios relating to the potential for introduction of infection. A range of surveillance strategies were identified to achieve and maintain a free farmed deer holding, and worked examples are presented. The surveillance system sensitivity for varying combinations of screening and confirmatory tests in live animals, animals at slaughter and on-farm deaths is also presented. Using a single test at a single point in time, none of the TB tests routinely used in farmed deer is able to achieve an acceptable probability of TB freedom. If repeat testing were undertaken, an acceptable probability of TB freedom could be achieved, with differing combinations of the surveillance system sensitivity, frequency of testing and risk of introduction. The probability of introduction of infection through the importation of infected deer was influenced by the use of a pre-movement test (assumed 90% test sensitivity and negative test results), the TB prevalence in the source herd and the number of animals imported. A surveillance system sensitivity of at least 81% was achieved with different combinations of annual live animal surveillance and surveillance of animals at slaughter or on-farm deaths. This methodology has broad applicability and could also be extended to other diseases in both deer and other species with relevance to trade in animals and animal products. 相似文献
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从国际经验来看,农产品批发市场不但是辐射面广、凝聚力强的产销中心,更是农产品价格形成中心.农产品批发市场的规范、有序运行对稳定农产品市场供求,引导农业生产顺利进行具有关键性的作用.而我国农产品批发市场由于发展滞后,运作方式原始、粗放,应有功能没有得到充分发挥.因此,加强基础设施建设,强化制度建设并实行农业产业化是进一步发挥农产品批发市场价格中心作用的关键措施. 相似文献
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WTO新一轮谈判于2004年8月1日达成框架协议,农业谈判在国内支持、出口竞争、市场准入等方面取得了一定的进展,是后续谈判的基础.运用ATPSM模型,在对欧盟、美国、日本、加拿大农业自由化改革模拟的基础上,探索了以框架协议为基础的多哈农业改革对发展中国家农产品贸易的可能影响. 相似文献
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Through empirical simulations of the Taiwanese rice market, we estimate the effects of agricultural policies designed to ensure optimal levels of two multifunctional outputs, groundwater recharge, and methane emissions. Optimal policy instruments differ by region to reflect land quality and the conditions of the aquifers in major rice production regions. The effects on rice production, resource allocation, and returns to farm assets differ as well.
相似文献
Richard N. BoisvertEmail: |
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