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121.
Pär Segerdahl 《Journal of Agricultural and Environmental Ethics》2007,20(2):167-193
Although the notion of natural behavior occurs in many policy-making and legal documents on animal welfare, no consensus has
been reached concerning its definition. This paper argues that one reason why the notion resists unanimously accepted definition
is that natural behavior is not properly a biological concept, although it aspires to be one, but rather a philosophical tendency
to perceive animal behavior in accordance with certain dichotomies between nature and culture, animal and human, original
orders and invented artifacts. The paper scrutinizes the philosophy of natural behavior as it developed in the organic movement
in response to a perceived contrast between industrialized and traditional agriculture. There are two reasons for focusing
on the organic movement: (i) the emphasis on “the natural” is most accentuated there and has a long history, (ii) everyday
life on organic farms presupposes human/animal interplay, which conflicts with the philosophical tendency to separate nature
from culture. This mismatch between theory and practice helps us see why, and how, the philosophy of natural behavior needs
to be reconsidered. The paper proposes that we understand farms as local human/animal cultures, and asks what we can mean
my natural behavior in such contexts. Since domestic animals adapt to agricultural environments via interaction with caretakers,
such interplay is analyzed as “hub” in these animals’ natural behavior. 相似文献
122.
Craig A. Peters 《黑龙江环境通报》2001,21(11):917-923
Fetal models of urinary tract disease have been used for many years and have provided unique and important insights into the pathophysiology of these conditions. This review will summarize the principal model systems used and the current directions of investigation. These models (including rabbit, opossum, sheep and recently swine) have demonstrated that in utero obstruction of the urinary tract alters renal growth, differentiation and produces stereotypical patterns of tissue response, particularly fibrosis. New molecular understanding of these processes has identified specific mechanisms that may be key elements in the development of renal dysfunction due to obstruction. These factors include the renin–angiotensin system (RAS) and its interaction with TGF-β in altering growth regulation and tissue fibrosis. These factors offer the prospect of clinical utility as markers of disease progression as well as pharmacologic therapy. Gene knockout systems have opened a new horizon of molecular models of congenital obstructive uropathy with insights into the role of the RAS in particular. It remains to be defined how closely these knockouts represent the human conditions they resemble. Continued application of fetal models of urinary obstruction, integrating large animal and knockout systems offers promise for improved diagnosis and treatment in these challenging conditions. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
123.
Kate M. Millar 《Journal of Agricultural and Environmental Ethics》2000,12(1):41-50
An analysis of the ethical impacts of the use of anAutomatic Milking System (AMS) is employed as a casestudy to illustrate the use of a form of bioethicalanalysis in technology assessment. The approach isbased on the Ethical Matrix, where `impacts' areassessed in terms of (lack of) respect for threeethical principles as applied to interest groups. Inthis case, only impacts on dairy cows are examined,and principally in terms of their behaviouralfreedom.In contrast to traditional milking systems, AMS, inprinciple, allow cows to present for milkingvoluntarily. So with AMS, it is claimed that dairymanagement relies on the autonomous interaction of thecow with her environment.One of the roles of bioethical analysis is to identifythe influence of rhetoric and symbolism in technologyassessment, e.g., with respect to the claimed`voluntariness' of cows' presentation. The AMS can beinstalled to allow cows three types of access, viz., i)free choice ii) rewarded access (RA) iii) obligatoryaccess (OA). Studies suggest the desire for milkremoval per se is not critical in the cow'sattendance at the AMS. Continued motivation to bemilked, required for the system to function,principally relies on RA and OA. Both RA and OA aresubject to numerous factors, such as: design of theAMS, location, etc. In turn, these can affect thecows' behavioural freedom and welfare.One of the aims of this approach is to illustrate theethical basis on which public policy is or can beformulated. 相似文献
124.
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126.
准确评价甲烷(CH4)的温室效应是制定有效减排路径的基础.首次采用新提出的、针对短寿命气候污染物(SLCP)设计的气候指标GWP-star (GWP*)对中国畜牧业CH4排放的温室效应进行定量评价,并与常用的GWP指标评价结果相比较.结果表明,GWP的视角下我国畜牧业CH4排放的温室效应持续增加.因此,畜牧业实现碳中和需要完全消除排放,或以增加碳汇、增加资源化利用的形式抵消每年稳定的CH4排放.在GWP*的视角下,2015~2019年间畜牧业CH4排放的温室效应较20年前有所减少,降低的热量相当于从20年前的大气中减少2.1×104万t CO2的热量,畜牧业只需每年有效降低0.3%的CH4排放则可在短期内实现自身碳中和.在中国畜牧业持续采取有效减排措施的情况下,采用GWP*的标准制定减排目标比用GWP制定的减排目标更早达到,但选择GWP还是GWP*需要综合考虑评价的目的、评价的时间尺度和实际可操作性. 相似文献
127.
目的:对某油田采出水用杀菌剂毒性进行评价,为员工安全操作及职业病防护提供依据。方法:采用动物试验方法,对某油田采出水用杀菌剂进行急性毒性实验研究。结果:该油田采出水用杀菌剂对SD大鼠的急性经口半数致死剂量(LD 50)为3160 mg/(kg·bw),属实际无毒级;对普通级成年新西兰白兔皮肤为中等刺激性,对眼睛为严重眼损伤/对眼造成不可逆影响;对普通级白化豚鼠皮肤为低致敏性。结论:该油田采出水用杀菌剂对皮肤、眼睛可能存在较大损伤,作业人员进行相关作业时应做好防护。 相似文献
128.
动物饲料中砷、铜和锌调查及分析 总被引:8,自引:1,他引:7
在广东省采集市售鸡、猪配合饲料样本70个和76个,调查评价其中砷、铜、锌形态和含量,并考察常用有机胂添加剂洛克沙胂(ROX)的稳定性.结果表明,鸡、猪料平均总As含量分别为3.6 mg·kg-1和6.5 mg·kg-1,总Cu含量为18.2 mg·kg-1和119.4 mg·kg-1,总Zn含量为124.6 mg·kg-1和486.2 mg·kg-1.按照国家相关限量标准,如考虑到可能添加了有机胂,饲料总As超标现象较少,猪料Cu、Zn超标现象较为普遍.Zn、Cu、As在饲料中添加量较高成为它们在禽畜粪中残留较高的根本原因.另外,有25.4%的饲料样本检出有机胂,且普遍同时含有As(Ⅲ)和As(Ⅴ)杂质.检出ROX和阿散酸(p-ASA)含量平均分别为7.0 mg·kg-1和21.2 mg·kg-1.鸡、猪料中各有24.3%和26.3%的样本检出有机胂.鸡料中常用ROX,而猪料常用p-ASA.ROX及其无机砷杂质在添加剂和饲料中均在室温至少30 d内保持形态稳定,说明饲料中较高含量的无机砷杂质很可能源自有机胂添加剂中的砷杂质.对相关从业人员而言,这是一种新的砷暴露途径. 相似文献
129.
牛眼虹膜定位算法研究及其在肉食品追溯系统中的应用 总被引:2,自引:0,他引:2
为实现动物个体的精确鉴别,提高肉食品的安全性,将动物虹膜识别技术引入到肉食品供应链中,构建了基于虹膜识别的肉食品安全可追溯系统业务流程,实现了肉食品"从农场到餐桌"的安全保障;并以牛眼虹膜为例,根据其非同心椭圆的结构特征和图像仿射变换不变特征的原理,提出了一种牛眼虹膜快速定位方法。将牛眼虹膜内、外边界分别转化为圆形,对内边界采用灰度均值法粗定位与"三点定圆"精定位相结合的方法实现,对外边界设计了一种逐点扫描分层圆环算法来精确拟合。实验结果表明:该方法避免了虹膜信息丢失,减少了空间参数的选择运算。 相似文献
130.
日本虎斑猛水蚤的重金属急性毒性及其作为标准测试生物的潜在意义 总被引:1,自引:0,他引:1
以静态实验法研究重金属Cu、Cd、Pb和Zn单独以及两两联合对日本虎斑猛水蚤(Tigriopus japonicus)的急性毒性效应,并分析其是否适宜作为我国海水重金属毒性测试的标准生物.结果显示,单独作用下,cu、Cd、Pb和Zn对受试生物的24 hLC50分别为0.26、0.14、0.40和0.65 mg·L-1,... 相似文献