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71.
72.
73.
T Taksdal J Wiik‐Nielsen S Birkeland P Dalgaard T Mørkøre 《Journal of fish diseases》2012,35(12):897-906
Pancreas disease (PD) is a viral disease of farmed salmonid fish, which causes huge economic losses. Pathological changes in skeletal muscle, pancreas and heart are hallmarks of PD. Stakeholders in the fish‐smoking industry have claimed that fillets from PD‐affected Atlantic salmon, Salmo salar L., are of poor quality. We therefore examined harvest‐ready, clinically healthy Atlantic salmon from a population of fish previously affected by PD. Histopathological changes in skeletal muscle tissues ranged from minor to severe. Fillet quality measurements showed that fish with severe skeletal muscle changes provided a paler raw fillet and a yellowish and harder cold‐smoked fillet than normal. PD had no significant effect on fillet gaping, bacteriological quality or off‐odour development during storage. An unexpected finding was a significant subendocardial fibrosis in 23% of the PD‐affected fish. The latter may indicate susceptibility to stress‐related heart failure. 相似文献
74.
Attia J Millot S Di-Poï C Bégout ML Noble C Sanchez-Vazquez FJ Terova G Saroglia M Damsgård B 《Fish physiology and biochemistry》2012,38(1):107-118
Following the development of demand-feeding systems, many experiments have been conducted to explore feeding motivation and
feed intake in farmed fish. This work aims to review a selection of studies in the field, focusing on three key factors, related
to demand feeding and fish welfare. Firstly, we outline how demand feeders should be considered when developing feed management
strategies for improving welfare in production conditions. Secondly, via laboratory demand-feeding experiments, we show self-feeding
activities depend not only on feeding motivation and social organisation, but also on individual learning capacity and risk-taking
behaviour. Thirdly, we report encouraging results demonstrating that when presented with two or more self-feeders containing
complementary foods, fish select a diet according to their specific nutritional requirements, suggesting that demand feeders
could be used to improve welfare by allowing fish to meet their nutritional needs. 相似文献
75.
Stine Kreutzmann Marc Bassompierre Anette Kistrup Thybo Lars Buch Søren Balling Engelsen 《Potato Research》2011,54(1):13-28
From a potato cultivar breeding database including 2,143 named cultivars and clones, 11 cultivars that spanned the major variation
in cultivar quality were selected for subsequent sensory and hedonistic applicability tests. A tailor-made sensory profile
of the cultivars was developed for four different cooking procedures: boiled, mashed, oven-fried and oven-cooked potatoes.
A sensory profile consisted of the four to five most important sensory attributes, and the data was combined with the applicability
data using multivariate data analysis. Ultimately, the variation in eating quality was evaluated in a hedonistic test with
expert evaluation of applicability. Three gourmet chefs prepared the different cultivars as boiled potatoes, mashed potatoes,
baked potatoes and oven-fried potatoes and evaluated the cultivars’ applicability, while a sensory panel consisting of nine
judges evaluated the sensory quality. The multivariate data analysis revealed a significant diversity amongst the cultivars
for the different cooking procedures. A single PCA bi-plot was able to provide a simple and clear overview of the gastronomic
diversity and possible applications of the different potato cultivars. 相似文献
76.
Trustworthy eco-labels provide consumers with valuable information on environmentally friendly products and thus promote green consumerism. But what makes an eco-label trustworthy and what can government do to increase consumer confidence? The scant existing literature indicates that low governmental involvement increases confidence. This suggests that government should just provide the basic legal framework for eco-labeling and leave the rest to non-governmental organizations. However, the empirical underpinning of this conclusion is insufficient. This paper analyses consumer confidence in different organic food labeling regimes with varying degrees of governmental involvement. Using unique and detailed survey data from the US, United Kingdom, Denmark, and Sweden, the analysis shows that confidence is highest in countries with substantial state involvement. This suggests that governments can increase green consumerism through active and substantial involvement in eco-labeling. 相似文献
77.
78.
Barley is one of the most important cereal crops grown for the livelihoods of the poor farmers of Tigray region in northern
Ethiopia. As many low input and marginal environments it has benefited less from the yield increases achieved by modern breeding.
This has been largely attributed due to genotype × environment intraction (GEI). To investigate the causes of GEI, ten barley
varieties including local checks (two farmers developed varieties, four modern varieties and three rare local varieties) were
tested over 21 environments. Participatory methods were applied to sample an adequate number of environments spanning the
regional diversity. The yielding ability and stability of the varieties was graphically depicted by GGE and PLSR biplot. There
were two major groups of environments, the central and northern highlands, the latter with less rainfall and poorer soils.
Rainfall per month and total nitrogen level were the environmental variables that differentiated these two groups. In Tigray,
rainfall in June and July were negatively correlated with yield, reflecting waterlogging problems. The different varieties
were either specifically or widely adapted across the two environments. The variety ‘Himblil’, originating in Tigray, was
the highest yielding and also most stable in the region of origin. However, it was inferior to improved varieties (Shege and
Dimtu) at high yield levels. The association of earliness with grain yield indicates that the trait can be effectively manipulated
within the existing materials. We recommend breeding for drought/water logging resistance based on selection in the target
environment as the best strategy to provide stable and high yielding varieties for Tigray. 相似文献
79.
J. Børve A. Stensvand 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(5):461-467
Effects of controlled atmosphere (CA) conditions on physiological disorders and fungal fruit decay on apple ‘Aroma’ were investigated. Fruit from three growing seasons were stored at 1% or 2% O2 (both at 2% CO2) at either 1°C or 3°C in small research units; controls were kept in the same ventilated rooms at the two temperatures (ambient air). The fruit were removed from storage after four or six months and assessed for fruit decay immediately afterwards and after two weeks at 20°C. Fruit quality parameters were recorded at the end of storage. On a three-year average, fruit stored in CA was less ripe at the end of storage. After both four and six months storage, CA reduced total decay (physiological disorders and fungal decay) by on average 70% and 45%, respectively, compared to storage in ambient air. Senescent breakdown was lower after CA storage for four months, but not after six months and not after simulated shelf life. Soft scald was lower when stored in CA both after cold storage at 1°C and simulated shelf life. After storage at 3°C there was lower incidence of soft scald when stored in CA after four months, but not after six months. For fungal fruit decay in general, there was no effect of low oxygen, however, 2% O2 gave slightly less bitter rot (Colletotrichum acutatum) than 1% O2 and significantly less than ambient air after simulated shelf life. Averaged over all oxygen levels, 1°C gave significantly less bitter rot than 3°C. It may be concluded that use of CA for storage of ‘Aroma’ is a good way of reducing development of physiological disorders. However, development of bitter rot seemed to be more influenced by temperature and storage time than by low O2. 相似文献
80.
David Nicholas Barton Ståle Navrud Heid Bjørkeslett Ingrid Lilleby 《Journal of Soils and Sediments》2010,10(2):186-201