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Estelle C.C. ?gren Jan Johansson Jenny Fr?ssling Helene Wahlstr?m Ulf Emanuelson Susanna Sternberg-Lewerin 《Acta veterinaria Scandinavica》2015,57(1)
Background
The Swedish control program for salmonella includes restrictions and on-farm control measures when salmonella is detected in a herd. Required control measures are subsidised by the government. This provides an opportunity to study costs for on-farm salmonella control. The aim of this study was to describe the costs for on-farm salmonella control in Swedish cattle herds and to investigate the effects of herd factors on these costs in dairy herds.Results
During the 15 years studied there had been a total of 124 restriction periods in 118 cattle herds; 89 dairy herds, 28 specialised fattening herds and three suckler herds. The average costs per herd for on-farm salmonella control was 4.60 million SEK with a median of 1.06 million SEK corresponding to approximately 490 000 and 110 000 EUR. The range was 0.01 to 41 million SEK corresponding to 1080 EUR to 4.44 million EUR per farm. The costs cover measures required in herd-specific control plans, generally measures improving herd hygiene. A mixed linear model was used to investigate associations between herd factors and costs for on-farm salmonella control in dairy herds. Herd size and length of the restriction period were both significantly associated with costs for on-farm control of salmonella with larger herds and longer periods of restrictions leading to higher costs. Serotype detected and administrative changes in the Swedish Board of Agriculture aiming at reducing costs were not associated with costs for on-farm salmonella control.Conclusions
On-farm control of salmonella in Swedish cattle herds incurred high costs but the costs also varied largely between herds. Larger herds and longer restriction periods increased the costs for on-farm control of salmonella in Swedish dairy herds. This causes concern for future costs for the Swedish salmonella control program as herd sizes are increasing. 相似文献2.
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林业机械设备寿命周期费用的计算、分析和应用研究 总被引：1，自引：0，他引：1
寿命周期费用理论是现代设备管理的重要理论。本文首先阐述了寿命周期费用的概念和各种计算方法,包括总费用的静态、动态计算方法和年平均费用的静态、动态计算方法。然后介绍了寿命周期费用分析步骤。在此基础上探讨了寿命周期费用分析在设备评价和设备更新效益计算中的应用方法。 相似文献
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为研究中国中规模生猪生产的成本与收益,探究提高生猪产业经济效益的途径,更好地指导生猪产业发展,运用2004—2013年数据,分析了中国中规模生猪生产环节每头生猪的成本与收益的各项具体指标,总结了中国中规模生猪生产环节成本收益的现状与变化趋势。研究发现物质与服务费用占生猪产业总成本的90%以上,饲料费用和仔畜进价不断上涨以及其所占成本比例较大是导致生猪生产成本上涨和效益低下的原因,生猪生产收益具有很大的波动性。最后提出了提高养殖技术与研究投入、推进规模化经营与组织化程度等降低生猪生产成本和保障食品安全与价格稳定、增强产业链联系、促进生态养殖等提高生猪生产收益的政策建议。 相似文献
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发展林下经济不仅有利于贫困地区农民增收、深化林权制度改革,同时还能促进生态保护。北京市发展林下经济,取得了显著成就,也存在许多问题和不足。该研究针对林下经济的现状和问题,基于抽样调查数据,采用净现值分析方法,集中关注栗树蘑、香菇和木耳3种林菌项目。结果显示,市场需求和林菌产量是决定林菌项目净现金效益的重要因素,价格补贴影响较小,菌种费对成本影响较大,劳动和农业机械费投入次之。因此,拓宽销售渠道、提高市场需求,改进生产技术是实现林菌项目又好又快发展的关键所在。 相似文献
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The impact of on-farm water saving irrigation techniques on rice productivity and profitability in Zhanghe Irrigation System,Hubei, China 总被引：3，自引：1，他引：3
Piedad?MoyaEmail author Lin?Hong David?Dawe Chen?Chongde 《Paddy and Water Environment》2004,2(4):207-215
To optimize the use of limited water resources, surface irrigation systems in parts of China have introduced a new water saving irrigation method for rice termed alternate wetting and drying (AWD). The basic feature of this method is to irrigate so that the soil alternates between periods of standing water and damp or dry soil conditions from 30 days after crop establishment up to harvesting. However, many Chinese rice farmers still practice the continuous irrigation method with late- season drying of the soil.A comparative assessment of these two methods of on-farm water management for rice was conducted at two sites within the Zhanghe Irrigation System (ZIS) in Hubei province of China for the 1999 and 2000 rice crops. The objective was to evaluate the impact of AWD on crop management practices and the profitability of rice production. In conjunction with irrigation district officials, two sites within ZIS were selected for study, one where AWD was supposed to be widely practiced (Tuanlin, TL) and one where it had not been introduced (Lengshui, LS). It was found that farmers at both sites do not practice a pure form of either AWD or continuous flooding. However, farmers in TL did tend to let the soil dry more frequently than their counterparts in LS.Because most farmers practice neither pure AWD nor pure continuous flooding, an AWD score was developed that measures the frequency with which farmers allow their soil to dry. This AWD score was not significantly correlated with yield after controlling for site and year effects and input use. AWD scores were also not correlated with input use. We conclude that AWD saves water at the farm level without adversely affecting yields or farm profitability. 相似文献
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阐述了农民专业合作经济组织特有的发展机理,指出它是分散弱小的广大农户为应对市场风险、提升市场竞争地位而自愿组织起来的内生型组织;从具有所有者与使用者同一、劳动联合、民主管理和共有产权等方面探讨了农民专业合作经济组织区别于其他经济组织的本质特征;剖析了农民专业合作经济组织的动力机制,指出市场环境和政府政策构成其外部发展动力,组织形成方式以及产权制度、激励制度等是其发展的内部动力,组织发展效率的提升主要依赖决策成本、监督成本和教育成本等非物质成本的降低。 相似文献
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Majid Azizi 《林业研究》2008,19(4):323-328
The objective of this research is to design a method for an appropriate alternative to supply poplar wood as raw material for wood and paper factories in Iran.Due to the destruction of the forests and lack of proper plantation,replacement of the forest wood by the fast growing wood is vital to satisfy all requirements of these factories.A hierarchy was used to prioritize benefits,opportunities,costs and risks (BOCR) using the Analytic Hierarchy Process (AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy was also created and prioritized by applying the Analytic Network Process (ANP).A total of four major control criteria in the system are prioritized where each one controls a network structure evaluated by using ANP.The final synthesis results of the system showed that internal poplar tree farming supplied by the forest product factories was the best choice among three potential alternatives (factory procurement,external procurement and mix procurement). 相似文献