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361.
Wim Wolff 《水产资源保护:海洋与淡水生态系统》1997,7(4):327-327
362.
Kathleen Neumann Berien S. Elbersen Peter H. Verburg Igor Staritsky Marta Pérez-Soba Wim de Vries Willem A. Rienks 《Landscape Ecology》2009,24(9):1207-1222
Livestock remains the world’s largest user of land and is strongly related to grassland and feed-crop production. Assessments
of environmental impacts of livestock farming require detailed knowledge of the presence of livestock, farming practices,
and environmental conditions. The present Europe-wide livestock distribution information is generally restricted to a spatial
resolution of NUTS 2 (province level). This paper presents a modelling approach to determine the spatial distribution of livestock
at the landscape level. Location factors for livestock occurrence were explored and applied to consistent and harmonized EU-wide
regional statistics to produce a detailed spatial distribution of livestock numbers. Both an expert-based and an empirical
approach were applied in order to disaggregate the data to grid level. The resulting livestock maps were validated. Results
differ between the two downscaling approaches but also between livestock types and countries. While both the expert-based
and empirical approach are equally suited to modelling herbivores, in general, the spatial distribution of monogastrics can
be better modelled by applying the empirical approach. 相似文献
363.
David A. Ramírez Wolfgang Grüneberg Maria I. Andrade Bert De Boeck Hildo Loayza Godwill S. Makunde Johan Ninanya Javier Rinza Simon Heck Hugo Campos 《Journal of Agronomy and Crop Science》2023,209(1):41-55
Sweetpotato is a crucial crop to guarantee food security in sub-Saharan Africa, and drought events are considered one of the most critical factors affecting sweetpotato productivity in this region. In this study, airborne imagery based on reflectance (NDVI, CIred-edge) and canopy temperature minus air temperature (dT) indices was used to characterize sweetpotato genotypes under drought treatments in Mozambique. Two field experiments established in rainy/hot (Trial A) and dry/cool (Trial B) seasons were assessed. In Trial A, 24 genotypes were subjected to early- (ESD), mid- (MSD) and late-season (LSD) drought stress treatments and compared against a control. In Trial B, 120 genotypes were subjected to LSD only. The percentage of reduction in vine weight (PRVW) under drought was related primarily to temporal variation of NDVI and CI, regardless of drought treatment and seasons. dT in relation to control (dTAmp) was associated with PRVW in ESD-Trial A and LSD-Trial B, whereas under LSD-Trial A, dTAmp was related to total fresh storage root weight (TRW). During the rainy/hot season, higher TRW reduction was promoted under ESD; however, under LSD, it was possible to identify productive genotypes able to withstand drought stress, highlighting their relevance for drought-tolerance selection purposes. 相似文献
364.
Hanne Digre Ulf Erikson Ekrem Misimi Bert Lambooij Hans Van De Vis 《Aquaculture Research》2010,41(8):1190-1202
An industrial and experimental electrical method for stunning farmed Atlantic cod in air and seawater (SW), respectively, were compared. The impacts of sedation with AQUI‐S? and exercise to exhaustion before electrical stunning were also assessed to monitor the possible depletion of rested muscle energy levels by electrical stunning. Stress (blood glucose, haematocrit, muscle pH, muscle excitability, high‐energy phosphates and rigor mortis) and flesh quality (fillet texture, colour, liquid leakage (LL), gaping, residual blood and K‐value) were assessed. For the industrial stunning method, an average of 41 V, 0.2 A dc was applied to individual cod for 18–27 s. For the SW method, a bipolar square wave current (170 Hz, 33% duty cycle) was applied for 5 s. After stunning, recovery was prevented by exsanguination in chilled SW. There were no differences (P>0.05) between the two stunning methods except for a higher ultimate fillet pH for cod stunned in air 8 days postmortem. Exercise before stunning depleted muscle energy levels at slaughter, increased LL and fillets had redder and darker flesh after storage on ice for 8 days. Electrical stunning (in air) of AQUI‐S?‐treated fish partly depleted muscle energy levels (pH 7.3, ATP 18.7 μmol g?1, PCr 70.1 μmol g?1). However, flesh quality was not affected. Unless pre‐rigor filleting is the chosen processing strategy, electrical stunning of cod seems to be a promising stunning method. 相似文献
365.
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367.
Tuyttens FA Vanhonacker F Langendries K Aluwé M Millet S Bekaert K Verbeke W 《Research in veterinary science》2011,91(2):327-332
Pork consumers know little about boar taint and the methods used to avoid it. As such, relevant information is necessary to assist consumers to judge the acceptability of different strategies to avoid boar taint. The effect of basic (T1) or extensive (T2) written information or T2 with supplementary audio–visual information (AV) on the opinion concerning immunocastration (IC), raising entire male pigs (EM) and surgical castration with anaesthesia (SA) as compared to castration without anaesthesia (SC) was investigated in a student population. Overall, IC was significantly preferred over SC. The information condition influenced the preference for IC and EM as compared to SC. Participants exposed to AV were more positive to IC than participants exposed to T1 and T2, and more positive to EM than participants exposed to T2. The impact of information condition was not affected by gender, farming experience, knowledge about the boar taint issue or personal relevance of pig welfare. Potential effects of providing background information and media campaigns on public surveys ought to be considered. Supplementary audio–visual information increased the impact of information provisioning. 相似文献
368.
369.
Sabrina Vairo Wim Van den Broeck Herman Favoreel Alessandra Scagliarini Hans Nauwynck 《Veterinary research》2013,44(1):22
The upper respiratory tract mucosa represents the first line of defense, which has to be overcome by pathogens before invading the host. Considering the economic and ethical aspects involved in using experimental animals for pathogenesis studies, respiratory mucosal explants, in which the tissue’s three-dimensional architecture is preserved, may be ideal alternatives. Different respiratory mucosal explant cultures have been developed. However, none of them could be inoculated with pathogens solely at the epithelium side. In the present study, equine nasal and nasopharyngeal explants were embedded in agarose (3%), leaving the epithelium side exposed to allow apical inoculation. Morphometric analysis did not show degenerative changes during 72 h of cultivation. The number of apoptotic cells in the mucosa slightly increased over time. After validation, the system was used for apical infection with a European strain (08P178) of equine arteritis virus (EAV) (107.6TCID50/mL per explant). Impermeability of agarose to virus particles was demonstrated by the absence of labeled microspheres (40nm) and a lack of EAV-antigens in RK13 cells seeded underneath the agarose layer in which inoculated explants were embedded. At 72 hpi, 27% of the EAV-positive cells were CD172a+ and 19% were CD3+ in nasal explants and 45% of the EAV-positive cells were CD172a+ and 15% were CD3+ in nasopharyngeal explants. Only a small percentage of EAV-positive cells were IgM+. This study validates the usefulness of a polarized mucosal explant system and shows that CD172a+ myeloid cells and CD3+ T lymphocytes represent important EAV-target cells in the respiratory mucosa. 相似文献
370.
Elijah I. Ohimain Wim Andriesse Martinus E.F van Mensvoort 《Journal of Soils and Sediments》2004,4(1):59-65