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41.
This paper focuses on the environmental and ethical attributes of food products and their production processes. These two aspects have been recently recognized and are becoming increasingly important in terms of signaling and of consumer perception. There are two relevant thematic domains: environmental and social. Within each domain there are two movements. Hence the paper first presents the four movements that have brought to the fore new aspects of food product quality, to wit: (1) aspects of environmental ethics (organic agriculture and integrated agriculture), and (2) social ethics (fair trade and ethical trade). Next, it describes how the actors in the movements (producers, retailers, NGOs, and governments) are organized and how consumers perceive each of the movements. From the perspective of the actors in the movements themselves, the movements are grouped into two “actors’ philosophies.” The first is a “radical” philosophy (the organic production and fair trade movements that arose in radical opposition to conventional agriculture or unfair trade relations), and the second is a “reformist” philosophy (the integrated agriculture and ethical trade movements that arose as efforts to modify but not radically change conventional agriculture). From the point of view of consumers, the classification of the movements is based on perceptions of the “domain” of the movements. That is, consumers tend to perceive the organic production movement and the integrated agricultural movement as a single group because they both deal with the environment. By contrast, consumers tend to group the fair trade movement and the ethical trade movement together because they both deal essentially with social ethics. Recently, key players such as large retailers and agribusinesses have adopted as part of their overall quality assurance programs both environmental and ethical attributes. Their involvement in and adoption of the goals of the movements have, however, generated tensions and conflicts. This is particularly true within the radical movements, because of concerns of cooptation. Finally, the paper identifies challenges faced by those promoting food products with environmental and social/ethical attributes as they attempt to communicate coherent signals to consumers at this crucial moment in the emergence of a mass market for these products. Jean -Marie Codron is a Senior Researcher at INRA and co-director of MOISA, a public joint research laboratory involved in the social sciences. His research interests focus on three main lines of research: economics of contracts, economics of the firm, and economics of market institutions, with applications to “complex” food sectors, where product quality is difficult to measure and/or to signal to the consumer. Lucie Sirieix is Professor of Marketing and Consumer Behaviour at SupAgro Montpellier, France, a national higher education establishment under the Ministry of Agriculture, Fisheries and Food. Within the MOISA research unit, her main research topics are variety seeking, risk and trust, environmental and ethical consumer concerns, and sustainable consumption. Her specific research areas include organic products, fair trade, and regional products. Thomas Reardon is Professor of Agricultural Economics at Michigan State University. His work focuses on globalization, consolidation in the retail and processing sectors, and their effects on agrifood systems and trade as well as on the economics of private quality and safety standards.  相似文献   
42.
1. The objective of this study was to determine the coefficient of pre-caecal digestion of P in maize (3.9 g/kg of total P, 0.83 g/kg of phytate P, 138 FTU [phytase units]/kg) and wheat (3.17 g/kg of total P, 1.94 g/kg of phytate P, 666 FTU/kg) in broilers according to the WPSA protocol.

2. For the diets, monosodium phosphate was used as an additional P supplement. Two sets of diets containing 200, 460 and 740 g/kg of wheat or 200, 500 and 740 g/kg of maize were formulated. A total of 288 21-d-old male broilers (Ross 308) were assigned to 24 cages (8 birds per cage) and the 6 test diets were assigned to cages. The coefficient of pre-caecal digestion of P was determined by the indicator method and linear regression.

3. In both ingredients, pre-caecal digestible P increased linearly with increasing inclusion levels of maize or wheat (P < 0.05). The coefficients of digestion of pre-caecal P were estimated to be 0.18 for wheat and 0.33 for maize.  相似文献   

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44.
Abandoned fields are perceived as potential habitats for species of threatened semi-natural dry grasslands. However, information is lacking regarding how the spontaneous colonization of abandoned fields depends on the broader spatial context. We recorded the occurrence of 87 target species in 46 abandoned fields and 339 dry grasslands. We tested the effect of the isolation of abandoned fields from source grasslands on the number of dry grassland species occurring in abandoned fields either with or without habitat characteristics being used as covariates. The isolation of the fields was calculated using the distance and area (I A ) or distance and species richness (I S ) of source habitats. I S always explained the number of grassland species in the abandoned fields better than I A . The effect of isolation became smaller or even non-significant with the inclusion of covariates; it also changed with the method used for measuring distance (edge-to-edge or center-to-center), and it was lower when other abandoned fields were considered as additional source habitats. The different performance of the two isolation measures can be explained by the weak species–area relationship in the grasslands, indicating differences in their habitat quality. Species richness is a better proxy of habitat importance in terms of propagule source than habitat area, and the new isolation measure is therefore suitable for studying the effects of landscape structure on species richness in landscapes presenting a weak species–area relationship, such as areas exhibiting pronounced effects of land-use history. Inclusion of habitat characteristics as covariates may considerably alter conclusions regarding the effect of isolation, which might actually be overestimated when assessed separately.  相似文献   
45.
Feline oral squamous cell carcinoma (FOSCC) is an aggressive cancer in domestic cats that has no effective treatment option when advanced. Preventative or early diagnostic measures are thus crucial. FOSCC is also a model for human head and neck SCC (HNSCC); strong risk factors in HNSCC include exposure to alcohol, tobacco, areca nut, and high-risk human papillomavirus. Previous studies have identified flea collar and tobacco smoke exposure, feeding canned tuna, canned cat food and cat foods with chemical additives, living in a rural environment, and having outdoor access as risk factors for FOSCC but there was no overlap in the risk factors between studies. In our study, risks for FOSCC were evaluated in an online epidemiologic survey study in 67 cats with FOSCC and 129 control cats. Clumping clay cat litter and flea collar use were significant risk factors for FOSCC on multiple logistic regression with odds ratios of 1.66 (95% CI 1.20–2.30) and 4.48 (95% CI 1.46–13.75) respectively. Crystalline silica is a carcinogen that may be present in all clay cat litters and tetrachlorvinphos is a carcinogen that is present in the most commonly used flea collars in our study. We recommend further investigation into the association between FOSCC and clay-based litter and/or flea collars containing tetrachlorvinphos.  相似文献   
46.
47.
Mass mortality events are ubiquitous in nature and can be caused by, for example, diseases, extreme weather and human perturbations such as contamination. Despite being prevalent and rising globally, how mass mortality in early life causes population-level effects such as reduced total population biomass, is not fully explored. In particular for fish, mass mortality affecting early life may be dampened by compensatory density-dependent processes. However, due to large variations in year-class strength, potentially caused by density-independent variability in survival, the impact at the population level may be high in certain years. We quantify population-level impacts at two levels of mass mortality (50% and 99% additional mortality) during early life across 40 fish species using age-structured population dynamics models. The findings from these species-specific models are further supported by an analysis of detailed stock-specific models for three of the species. We find that population impacts are highly variable between years and species. Short-lived species that exhibit a low degree of compensatory density dependence and high interannual variation in survival experience the strongest impacts at the population level. These quantitative and general relationships allow predicting the range of potential impacts of mass mortality events on species based on their life history. This is critical considering that the frequency and severity of mass mortality events are increasing worldwide.  相似文献   
48.
New Forests - Seed dormancy is an adaptive mechanism that allows seed germination under suitable environmental conditions. Germination of stored dormant seeds proceeds after dormancy breaking...  相似文献   
49.
Precise field experiments were established on two sites with winter wheat under different soil-climatic conditions in the Czech Republic. Four treatments were fertilized with same dose of nitrogen (200 kg N ha?1) and increasing dose of sulphur (0, 10, 20 and 40 kg S ha?1) using nitrogen–sulphur (N–S) fertilizer with calcium sulphate form. Soil and plant aboveground biomass samples were taken in the stages of development BBCH 26–28; 30–32; 37–39; 49–51. The winter wheat grain yield ranged between 7.20 and 10.86 t ha?1 and had an increasing trend with increasing sulphur dose. Although the differences were usually not statistically significant, there were found increasing tendencies of bioavailable sulphur content in soil with increasing S split doses. Soil S content decreased with time probably due to plant uptake. Sulphur dose did not influence the S content in plant aboveground biomass. The total S contents in grain after harvest ranged between 0.09% and 0.14% and were not significantly influenced with the fertilizing treatment. The same statement is valid for the S content in straw, which ranged between 0.03% and 0.11%. Both, S content in winter wheat seeds and straw were strongly influenced by the site conditions.  相似文献   
50.
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