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111.
Virginie Martin Ioannis Vouldoukis Javier Moreno David McGahie Sylvie Gueguen Anne-Marie Cuisinier 《Veterinary research》2014,45(1):69
Control of canine leishmaniasis is an important objective for the benefit of dogs living in or visiting endemic areas and for public health because of the zoonotic nature of this disease. Resistance or susceptibility to developing canine leishmaniasis after exposure to Leishmania infantum is primarily determined by the ability of the immune system to develop an appropriate Th1-dominated specific response to the parasite. For this reason there is a need for effective canine vaccines that can decrease the number of dogs developing progressive infections. In this study, we followed the impact of the LiESP/QA-21 canine vaccine (composed of excreted-secreted proteins of L. infantum and the QA-21 saponin adjuvant), recently launched commercially in Europe, on selected humoral and cellular immune parameters following an infectious intravenous challenge with L. infantum promastigotes administered one year after the primary vaccine course. We also followed parasitological parameters to determine the parasitological status of the challenged dogs. In contrast to controls, vaccinated dogs retained significantly stronger cell-mediated immune responses against the parasite despite a virulent challenge and had significantly lower mean parasite burdens at the end of the study, associated with a lower probability of developing active infections. These results confirm that the immune responses generated by vaccination with LiESP/QA-21 are still effective against an intravenous challenge one year after the primary vaccine course. 相似文献
112.
113.
Edith?Le?CadreEmail author Sophie?Génermont Farooq?Azam Sylvie?Recous 《Biology and Fertility of Soils》2004,40(3):178-180
After dissolution of fertiliser granules, a high nitrogen concentration is recovered in the immediate vicinity of granules, which may enhance damaging processes like nitrite accumulation or ammonia volatilisation. Based on the diffusion equations of Cranck, the granule-soil microsite was modelled to obtain the actual fertilised surface plot and the effective rate of N application on this surface. Parameterisation of the diffusion coefficient of solutes consisted of a temperature and soil texture correction. The model was tested against an experimental data set obtained from soil incubations at two soil water contents (21.2% m3 m–3 and 28.3% m3 m–3) and two temperatures (4°C and 25°C) by comparing NH4+ recovery at various distances from the granules. The simulated radius of the granule-soil microsite was more affected by the water content than by the temperature. The model is very accurate because 95–100% of total NH4+ applied was recovered in the modelled surface depending on the experimental conditions (temperature and water content). The model was simple enough to be easily integrated into larger models dealing with surface-applied granule fertilisers. 相似文献
114.
Alowanou Géorcelin Goué Azando Erick V. B. Adenilé Adam D. Koudandé Delphin O. Chrysostome Christophe A. M. Hounzangbé-Adoté Sylvie M. 《Tropical animal health and production》2020,52(1):309-319
Tropical Animal Health and Production - Gastrointestinal (GI) nematodes remain a major constraint on livestock production throughout the world. This study assessed the in vivo efficacy of the... 相似文献
115.
Estimating illegal and unreported catches from marine ecosystems: a basis for change 总被引:4,自引:0,他引:4
Tony J Pitcher Reg Watson Robyn Forrest Hreiðar Þór Valtýsson & Sylvie Guénette 《Fish and Fisheries》2002,3(4):317-339
To evaluate the impacts of fishing on marine ecosystems, the total extraction of fish must be known. Putting a figure on total extraction entails the difficult task of estimating, in addition to reported landings, discards, illegal and unmandated catches. Unreported catches cast various types of shadow, which may be tracked and estimated quantitatively. Some shadows of unreported catches are reviewed, for example, an innovative, well‐funded NGO publicizes illegal catch in the Southern Ocean. For various reasons, official figures often have the implicit but unacceptable assumption that such categories are null. We present an estimation procedure based on adjustment factors taken from observer reports, correspondents and published information that track changes in a regulatory regime, and hence reflect incentives and disincentives to misreport. Monte Carlo simulations address uncertainty using multiple sources of information to provide upper and lower estimates. Once in place, this method provides preliminary estimates that may be refined without disruption. The method is demonstrated for fisheries in Iceland and Morocco. We use a ‘by‐species’ approach for Icelandic cod and haddock, while the Moroccan catch is divided into demersal and pelagic categories. Results suggest that Icelandic cod catches may have been underestimated by between 1 and 14% at different times, and haddock by between 1 and 28%. Underestimation of Moroccan catches appears to have been as much as by 50%. These case studies show that it is possible to obtain estimates of misreporting, even when direct data are lacking. Our method encourages transparency because sources of information are presented so that uncertain values are easily identified, offering a basis for comment, collaboration and refinement in estimating illegal and unreported fishing. 相似文献
116.
117.
Pierre Laurent Suzanne Dunel-Erb Claudine Chevalier Jacques Lignon 《Fish physiology and biochemistry》1994,13(5):353-370
The aim of this work was to determine the kinetics of the dramatic development of the gill chloride cells (CCs) during adaptation
of the salmonid Oncorhynchus mykiss to an ion-poor environment.
To monitor cell division, the incorporation in the mitotic cell DNA of bromo-deoxyuridine (BrdUrd) was visualized with a monoclonal
antibody. The density of labelled nuclei was used as an index of cellular division (proliferation), concomitantly with morphometry
of phenotypic changes monitored with SEM.
In the filament epithelium, a phase of CC differentiation occurred within 12h after the transfer, followed by a delayed phase
of cell proliferation (48h). In the lamellar epithelium, the present study demonstrates the absence of cell proliferation
after ion-poor water transfer. The conclusion is that proliferation (mitosis) is important in the primary filament whereas
differentiation and migration (from the filament) is the main mechanism for the appearance of CCs on the secondary lamellae.
The present study suggests that cortisol promoted differentiation, but not division, of cells. CCs, presumably premature,
were stained by anti-cortisol monoclonal antibody indicating the presence of cortisol. No mature CCs were stained.
Growth hormone (oGH, ratGH) increased the rate of cell division both in lamellar and filament epithelium. 相似文献
118.
Marie Baltzinger Frédéric Archaux Marion Gosselin Richard Chevalier 《Annals of Forest Science》2011,68(2):395-406
• Introduction
Most temperate forests are managed for wood production, and some forestry practices generate typical environmental features such as roads, paths, ditches and tractor ruts, which are likely to affect forest species distribution. 相似文献119.
Martín-Hernández C Bénet S Marvin-Guy LF 《Journal of agricultural and food chemistry》2005,53(22):8607-8613
Several methods for extraction and quantification of proteins from lecithins were compared. Extraction with hexane-2-propanol-water followed by amino acid analysis is the most suitable method for isolation and quantification of proteins from lecithins. The detection limit of the method is 15 mg protein/kg lecithin, and the quantification limit is 50 mg protein/kg. The relative repeatability limits for samples containing 0-500 and 500-5000 mg protein/kg sample were 12.6 and 7.5%, respectively. The protein recovery ranged between 101 and 123%. The protein content has been determined in different kinds of lecithins. The results were as follows: standard soy lecithins (between 232 and 1338 mg/kg), deoiled soy lecithin (342 mg/kg), phosphatydylcholine-enriched soy lecithins (not detectable and 163 mg/kg), sunflower lecithins (892 and 414 mg/kg), and egg lecithin (50 mg/kg). The sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein patterns of the standard soy and sunflower lecithins are very similar to those of soy flour. The protein profile of the egg lecithin shows several bands with a broad range of molecular masses. The molecular masses of the main proteins of soy lecithins and soy flour have been determined by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and ranged from 10.5 to 52.2 kDa. Most of the major proteins from soy and sunflower lecithins identified by MALDI-MS and electrospray tandem MS belong to the 11S globulin fraction, which is one of the main fractions of soy and sunflower seeds. In addition, the seed maturation protein P34 from the 7S globulin fraction of soy proteins has also been identified in soy lecithins. This protein has been reported as the most allergenic protein in soybean. 相似文献
120.
Nicolas Morellet Bram Van Moorter Bruno Cargnelutti Jean-Marc Angibault Bruno Lourtet Joël Merlet Sylvie Ladet A. J. Mark Hewison 《Landscape Ecology》2011,26(7):999-1010
Understanding how patterns of habitat selection vary in relation to landscape structure is essential to predict ecological
responses of species to global change and inform management. We investigated behavioural plasticity in habitat selection of
roe deer (Capreolus capreolus) in relation to variable habitat availability across a heterogeneous agricultural landscape at the home range and landscape
scales. As expected, woodland was heavily selected, but we found no functional response for this habitat, i.e. no shift in
habitat selection with changing habitat availability, possibly due to the presence of hedgerows which were increasingly selected
as woodlands were less abundant. Hedgerows may thus function as a substitutable habitat for woodlands by providing roe deer
with similar resources. We observed a functional response in the use of hedgerows, implying some degree of landscape complementation
between hedgerows and open habitats, which may in part compensate for lower woodland availability. We also expected selection
for woodland to be highest at the wider spatial scale, especially when this habitat was limiting. However, our results did
not support this hypothesis, but rather indicated a marked influence of habitat composition, as both the availability and
distribution of resources conditioned habitat selection. There was no marked between-sex difference in the pattern of habitat
selection at either scale or between seasons at the landscape scale, however, within the home range, selection did differ
between seasons. We conclude that landscape structure has a marked impact on roe deer habitat selection in agricultural landscapes
through processes such as landscape complementation and supplementation. 相似文献