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Vincent Buchet Elodie Coquard Armelle Sévère & Hervé Barone 《Aquaculture Research》2008,39(4):420-426
Sea bass, Dicentrarchus labrax (mean weight: 748±13 g), were maintained before and during vitellogenesis in 1, 3, 8, 16 and 32 m3 tanks, and then they were transferred to 2 m3 tanks, for the spawning season. During the first 2 months of the experiment, the growth rates were significantly lower in smaller tanks (1 m3). In August, the oocyte diameters were significantly lower in smaller tanks (1, 3 and 8 m3) than in larger (16–32 m3) tanks. At the end of the experiment, the fish mean weight in the 1 m3 tanks was significantly lower than in the 3 m3 tanks, but oocyte diameters and plasma oestradiol concentrations were not significantly different between the volumes. This shows a longer acclimation requirement in smaller volume rearing. Although all the females had not spawned, one spawn at least was collected in each volume. The variation in conditioning volume has not blocked the spawning process. The qualitative and quantitative characteristics of spawns were not significantly different between volumes. The conditioning volume of 3 m3 seems to be a minimal volume required to obtain good reproduction of sea bass. 相似文献
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Georgina Catacora-Vargas Rosa Binimelis Anne I. Myhr Brian Wynne 《Agriculture and Human Values》2018,35(2):489-513
The importance of socio-economic impacts (SEI) from the introduction and use of genetically modified (GM) crops is reflected in increasing efforts to include them in regulatory frameworks. Aiming to identify and understand the present knowledge on SEI of GM crops, we here report the findings from an extensive study of the published international scientific peer-reviewed literature. After applying specified selection criteria, a total of 410 articles are analysed. The main findings include: (i) limited empirical research on SEI of GM crops in the scientific literature; (ii) the main focus of the majority of the published research is on a restricted set of monetary economic parameters; (iii) proportionally, there are very few empirical studies on social and non-monetary economic aspects; (iv) most of the research reports only short-term findings; (v) the variable local contexts and conditions are generally ignored in research methodology and analysis; (vi) conventional agriculture is the commonly used comparator, with minimal consideration of other substantially different agricultural systems; and (vii) there is the overall tendency to frame the research upon not validated theoretical assumptions, and to over-extrapolate small-scale and short-term specific results to generalized conclusions. These findings point to a lack of empirical and comprehensive research on SEI of GM crops for possible use in decision-making. Broader questions and improved methodologies, assisted by more rigorous peer-review, will be required to overcome current research shortcomings. 相似文献
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Balmford A Bennun L Brink BT Cooper D Côte IM Crane P Dobson A Dudley N Dutton I Green RE Gregory RD Harrison J Kennedy ET Kremen C Leader-Williams N Lovejoy TE Mace G May R Mayaux P Morling P Phillips J Redford K Ricketts TH Rodríguez JP Sanjayan M Schei PJ van Jaarsveld AS Walther BA 《Science (New York, N.Y.)》2005,307(5707):212-213
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Georgina C. A. Johnston Kelly A. Wood Karen V. Jackson Nigel R. Perkins Steven T. Zedler 《Journal of veterinary pharmacology and therapeutics》2020,43(1):38-49
Intra-articular (IA) hyaluronic acid (HA) is commonly used to treat equine arthritis. Inflammatory response or “joint flare” is a recognized potential side effect. However, the incidence and severity of inflammation following IA HA injection in horses is not well documented. This study compared the effects of two IA HA formulations of different molecular weight (MW) and a saline control on clinical signs and synovial fluid markers of inflammation in normal equine joints. Eight adult horses each had three healthy fetlock joints randomly assigned to treatment with either 1.4 mega Dalton HA, 0.8 mega Dalton HA or saline control once weekly for three weeks. Clinical evaluation and synovial fluid analysis were performed by blinded assessors. Outcomes of interest were lameness score, joint effusion score and synovial fluid white cell count and differential, total protein, viscosity and serum amyloid A. Joints injected with HA developed significant mild-to-moderate inflammatory responses often associated with lameness and joint effusion compared with saline control joints. The higher MW HA formulation elicited a significantly greater inflammatory response than the lower MW HA after the first injection. In HA injected joints, viscosity remained poor for the entire study. Both IA HA formulations in this study induced an inflammatory response in healthy equine joints. This may have implications for the use of HA in equine joints. The findings in this study are limited to the two HA formulations used. Further investigation of different HA formulations and the use of HA in normal and arthritic equine joints is warranted. 相似文献
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Unravelling landslide risk: soil susceptibility,agro‐forest systems and the socio‐economic profile of rural communities in Italy 下载免费PDF全文
Landslides are considered a form of physical soil degradation and are concentrated, especially in southern European countries, on inland and marginal rural areas. Low‐density, economically disadvantaged and poorly accessible areas are assumed to share a high landslide occurrence probability. However, an empirical verification of this assumption is still lacking for Mediterranean countries. This study investigates the spatial relation between a composite index of landslide risk and more than 100 indicators at the municipal level in Italy – a country with high landslide risk – exploring multiple territorial dimensions (population dynamics and settlements, job market and human capital, economic specialization and competitiveness, quality of life, agriculture and rural development, territory and environment). We combine nonparametric correlation, principal component analysis and hierarchical clustering, to profile municipalities according to their levels of landslide risk. The high landslide risk in certain areas of Italy is related to specific socio‐economic attributes (depopulation, ageing, tourism specialization, low density of economic activities, modest participation to the job market and crime intensity) and agro‐environmental features (low‐intensity cropping systems, natural landscapes and water resource availability). 相似文献