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71.
Marc B. M. BRACKE Rudi M. DE MOL Satoshi HIRAHARA Katsuji UETAKE Toshio TANAKA 《Animal Science Journal》2011,82(1):150-160
To increase the validity of evaluations and facilitate expansion and maintenance of assessment systems, we constructed a database of studies on the welfare of laying hens around the world. On the basis of this database, we devised a science‐based welfare assessment model. Our model includes measurements, levels and weightings based on the scientific studies in the database, and can clarify the advantages and disadvantages of housing systems for laying hens from the viewpoint of the five freedoms. We also evaluated the usefulness of our model by comparing it with environment‐based Animal Needs Index (ANI), another science‐based model called FOWEL, and animal‐based measurements. Our model showed that freedom from injury, pain and disease, and freedom from discomfort were more secure in the cage system, while non‐cage systems scored better for natural behavior and freedom from fear and distress. A significant strong‐positive correlation was found between the animal‐based assessment and the total scores of ANI (rs = 0.94, P < 0.05), FOWEL (rs = 0.99, P < 0.05) or our model (rs = 0.99, P < 0.05), which indicate that these different approaches to welfare assessment may be used almost interchangeably to ‘measure’ a common property (‘overall laying hen welfare’). However, assessments using our model and FOWEL were more sensitive than ANI and can be applied to cage systems, which suggest that our model and FOWEL may have added value. 相似文献
72.
Fifty-nine of the 65 dairy farms with cubicle sheds in the Norwegian county of Oppland in 1990 were included in a study of rearing accommodation, cubicle refusal and mastitis incidence. The farmers recorded the favoured resting location of the individual cows and heifers throughout the final week of pregnancy as well as during calving. The observations were matched with individual records of mastitis cases during the first 30 days after calving. Mastitis incidence in the heifers was analysed by logistic regression using rearing accommodation and cubicle refusal as independent variables, controlling for herd as a clustering factor. Cubicle refusal was found in 29% of the heifers, but in only 3% of older cows. The results of the analysis indicated a tendency for cubicle refusal to be associated with an increased mastitis incidence among the heifers (OR = 2.2, c.i.95%OR = 0.9-5.4, P = 0.08). Cubicle refusal accounted for 21% (0-32%) of the mastitis cases in the study population (PAF = 0.21). 相似文献
73.
麦秸在建筑材料中的应用——定向结构麦秸板及其房屋系统 总被引:2,自引:0,他引:2
定向结构麦秸板(OSSB)具有质轻、强度高、尺寸稳定性好和绿色环保的特点,其各项物理力学性能完全可与木质定向刨花板相媲美,是一种可作为建筑材料使用的结构板材,可应用于轻钢屋架OSSB房屋系统。 相似文献
74.
75.
风机壳体零件按传统加工方法一般是先加工轴承孔,然后以轴承孔为定位基准铣削风机安装平面、钻紧固螺栓孔、背锪螺栓紧固平面,费时费力。经过加工工艺改进,变背锪平面为铣平面,变单件加工为四件同时加工,减少了安装次数,大大提高了生产效率和加工精度。本文阐述了风机壳体的工艺改进,并对关键零件利用NX进行了强度有限元分析。 相似文献
76.
77.
县域交通对农村房屋建筑区景观格局的影响研究——以广东佛山市三水区为例 总被引:2,自引:0,他引:2
基于实证分析法,运用GIS空间分析、景观指数以及回归分析法,分析县域视角下交通沿线农村房屋建筑区景观类型与空间分布规律、道路网络影响范围内的农村房屋建筑区景观异质性和稳定性。以佛山市三水区为例,研究不同等级道路与农村房屋建筑密度、楼层高度及空间格局的相互关系,从而探讨县域交通对农村房屋建筑景观格局的影响。研究结果表明:农村房屋建筑区以高密度低矮类型为主,农村居民点整理潜力巨大;总体上农村房屋趋近道路分布;道路级别与其空间吸引力呈相反趋势;道路影响下农村低密度房屋建筑区空间结构最不稳定;低等级道路对农村房屋建筑区密度和楼层的影响大于高等级道路;村庄规划与布局需综合考虑道路级别的影响。 相似文献
78.
用热管换热器回收密闭式畜禽舍冬季换气中的余热 总被引:1,自引:0,他引:1
首次将热管换热器用于回收密闭式畜禽舍冬季换气中的余热。对热管换热器作了传热设计计算,对给定工况进行了优化参数选定。根据设计参数而安装调试的热管换热器在实际运行中实测值略高于计算值,说明设计计算是合理的。热管换热器具有热效率高、节能等优点,有一定的推广价值。 相似文献
79.
作为全国33个农村土地改革试点县之一,义乌市率先探索农村宅基地改革“三权分置”路径,其实质是拓展宅基地的产权权能。通过落实农村集体所有权、保障集体经济组织成员资格权、适度放活宅基地使用权,极大地拓展了宅基地所有权、占有权、处置权、收益权等权利、权能。但是,也存在权能拓展不充分与权力运行失范的双重困惑,需要细分宅基地“三权权属”,加快相关法律衔接,规避“适度放活”风险。 相似文献
80.
As the new century approaches, the problem of aging society is confronting us. The housing market for elders is becoming a constituent of the housing market in China. It is an indisputable way that credit and insurance play roles in the process of promoting the elder's housing consumption. This paper introduces a different kind of credit-inverse mortgage, suitable for elders, and explores its characteristics and three main forms. For weak abilities of elders to resist risks, this paper also explores some insurance forms that can help elder housing consumers. 相似文献