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1.
Antoine Levasseur Julie Arsenault Julie Par 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(5):469
The objectives of the study were to describe the regional and provincial incidence rates and the weekly distribution of 842 reported West Nile virus (WNV) cases in horses in Canada between 2003 and 2019. This study also investigated characteristics of cases reported to the Canadian Food Inspection Agency (CFIA) between 2015 and 2019. The western region (British Columbia, Alberta, Saskatchewan, and Manitoba) had higher incidence rates than the eastern region (Ontario, Quebec, and Atlantic provinces) and overall, Saskatchewan registered the highest incidence. Over the study period, an earlier weekly preliminary onset of WNV cases was observed in the western region. The vast majority of cases were unvaccinated (96%), most cases were Quarter Horses (68%) and the risk of mortality was 31.9%. The findings of this study may be useful in informing veterinary equine practitioners about measures to prevent WNV disease in horses in Canada. 相似文献
2.
Antoine Leduc Sylvain Souchet Marine Gel Fabienne Le Provost Marion Boutinaud 《Journal of animal science》2021,99(7)
In the dairy cow, negative energy balance affects milk yield and composition as well as animal health. Studying the effects of negative energy balance on dairy cow milk production is thus essential. Feed restriction (FR) experiments attempting to reproduce negative energy balance by reducing the quantity or quality of the diet were conducted in order to better describe the animal physiology changes. The study of FR is also of interest since with climate change issues, cows may be increasingly faced with periods of drought leading to a shortage of forages. The aim of this article is to review the effects of FR during lactation in dairy cows to obtain a better understanding of metabolism changes and how it affects mammary gland activity and milk production and composition. A total of 41 papers studying FR in lactating cows were used to investigate physiological changes induced by these protocols. FR protocols affect the entire animal metabolism as indicated by changes in blood metabolites such as a decrease in glucose concentration and an increase in non-esterified fatty acid or β-hydroxybutyrate concentrations; hormonal regulations such as a decrease in insulin and insulin-like growth factor I or an increase in growth hormone concentrations. These variations indicated a mobilization of body reserve in most studies. FR also affects mammary gland activity through changes in gene expression and could affect mammary cell turnover through cell apoptosis, cell proliferation, and exfoliation of mammary epithelial cells into milk. Because of modifications of the mammary gland and general metabolism, FR decreases milk production and can affect milk composition with decreased lactose and protein concentrations and increased fat concentration. These effects, however, can vary widely depending on the type of restriction, its duration and intensity, or the stage of lactation in which it takes place. Finally, to avoid yield loss and metabolic disorders, it is important to identify reliable biomarkers to monitor energy balance. 相似文献
3.
Antoine LF Gady Freddy WK Hermans Marion HBJ Van de Wal Eibertus N van Loo Richard GF Visser Christian WB Bachem 《Plant methods》2009,5(1):13-14
Background
The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal. 相似文献4.
Marine Remize Frdric Planchon Matthieu Garnier Ai Ning Loh Fabienne Le Grand Antoine Bideau Christophe Lambert Rudolph Corvaisier Aswani Volety Philippe Soudant 《Marine drugs》2022,20(1)
The production of polyunsaturated fatty acids (PUFA) in Tisochrysis lutea was studied using the gradual incorporation of a 13C-enriched isotopic marker, 13CO2, for 24 h during the exponential growth of the algae. The 13C enrichment of eleven fatty acids was followed to understand the synthetic pathways the most likely to form the essential polyunsaturated fatty acids 20:5n-3 (EPA) and 22:6n-3 (DHA) in T. lutea. The fatty acids 16:0, 18:1n-9 + 18:3n-3, 18:2n-6, and 22:5n-6 were the most enriched in 13C. On the contrary, 18:4n-3 and 18:5n-3 were the least enriched in 13C after long chain polyunsaturated fatty acids such as 20:5n-3 or 22:5n-3. The algae appeared to use different routes in parallel to form its polyunsaturated fatty acids. The use of the PKS pathway was hypothesized for polyunsaturated fatty acids with n-6 configuration (such as 22:5n-6) but might also exist for n-3 PUFA (especially 20:5n-3). With regard to the conventional n-3 PUFA pathway, Δ6 desaturation of 18:3n-3 appeared to be the most limiting step for T. lutea, “stopping” at the synthesis of 18:4n-3 and 18:5n-3. These two fatty acids were hypothesized to not undergo any further reaction of elongation and desaturation after being formed and were therefore considered “end-products”. To circumvent this limiting synthetic route, Tisochrysis lutea seemed to have developed an alternative route via Δ8 desaturation to produce longer chain fatty acids such as 20:5n-3 and 22:5n-3. 22:6n-3 presented a lower enrichment and appeared to be produced by a combination of different pathways: the conventional n-3 PUFA pathway by desaturation of 22:5n-3, the alternative route of ω-3 desaturase using 22:5n-6 as precursor, and possibly the PKS pathway. In this study, PKS synthesis looked particularly effective for producing long chain polyunsaturated fatty acids. The rate of enrichment of these compounds hypothetically synthesized by PKS is remarkably fast, making undetectable the 13C incorporation into their precursors. Finally, we identified a protein cluster gathering PKS sequences of proteins that are hypothesized allowing n-3 PUFA synthesis. 相似文献
5.
Billard Antoine Bauer Rodolphe Mothe Frédéric Colin Francis Christine Deleuze Longuetaud Fleur 《European Journal of Forest Research》2021,140(6):1401-1416
European Journal of Forest Research - Studies on wood basic density (BD) vertical variations become essential to predict more accurately the within-stem distributions of biomass and wood quality in... 相似文献
6.
M Velinova C Thielen F Mélot J Donga S Eicher E Heinen N Antoine 《The Veterinary record》2001,149(20):613-617
Samples of normal bovine palatine tonsils were examined by light and electron microscopy. Like human tonsils, they were composed of crypts, subepithelial areas, follicles, and T-dependent zones, but their well-developed capsule subdivided the lymphoid tissue by connective septa. B cells formed the major lymphoid component. The follicles and T-dependent zones had morphological and histochemical features typical of peripheral lymph organs. Follicular dendritic cells were isolated and shown to be similar to human follicular dendritic cells. 相似文献
7.
Parklands are mixtures of trees and shrubs that farmers select for certain functions. In the Sahel, parklands are cultivated
together with staple food crops, such as millet and sorghum. Parkland trees are sources of foods, including fruits, fats,
oils, leafy vegetables, nuts and condiments that complement food crops in the local diet. Despite their socio-economic and
ecological role, many studies have shown that the parklands are degrading very rapidly. Therefore, there is a need to undertake
restoration actions that are based on a clear understanding of the livelihood context, such as the wealth status of the farmers,
in which these agroecosystems are evolving. Thus, we conducted a wealth survey with rural communities in two different farming
systems of Burkina Faso that are the cereal-based system in the “Plateau Central” and the cotton-based system in the “Boucle
du Mouhoun”. A total of twelve villages were sampled, six villages for each system. The Participatory Analysis of Poverty
and Livelihood Dynamics (PAPoLD) method was used by rural farmers to rank farmer households of their communities according
to their wealth status. The results revealed that 70% of households in the Plateau Central and 56% in the “Boucle du Mouhoun”
managed to escape poverty, and became wealthy. However, 2% of households of the villages in the Plateau Central and 6% in
“Boucle du Mouhoun” fell into poverty in the same period whereas 9 and 12% remained poor in these zones, respectively. The
main causes associated with households getting out of poverty are subsidies for cotton, external revenues from relatives working
in towns and gardening activities. Death of spouse, illness, high number of people in the household and indebtedness are the
main causes that lead into poverty. The implications of these findings in designing appropriate policies and management options
for a sustainable management of agroforestry parklands under different land use systems were finally discussed. 相似文献
8.
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10.
Agricultural studies of GM maize and the field experimental infrastructure of ECOGEN 总被引:4,自引:9,他引:4
Mathias Neumann Andersen Christophe Sausse Bernard Lacroix Sandra Caul Antoine Messan 《Pedobiologia》2007,51(3):175-ECOGEN
Within the ECOGEN project, long-term field experiments with genetically modified maize, Zea mays L. were conducted to study agro-ecological effects on the soil fauna and agro-economic implications of the technology. Here, we describe the study-sites, experimental layout and results of agro-economic relevance. Experiments were conducted during 2002–2005 in Denmark (Foulum), northern France (Varois) and the Midi-Pyrenees region of southern France (Narbons). MON810 Bacillus thuringiensis (Bt)-varieties expressing the Cry1Ab protein, and a T25 glufosinate-ammonium (Basta) tolerant variety expressing the pat-gene encoding phosphinotrinacetyl-transferase were compared with near-isogenic non-Bt varieties, and conventional maize varieties. At Foulum, the maize was harvested for silage. There were no significant differences in yield between Bt-maize and a near-isogenic non-Bt variety, while a small difference in N-concentration of dry matter was detected in 1 year in a range of a measured quality parameters. Similar yield and quality were found in ploughed and reduced tillage treatments in all varieties. At Varois, the maize was harvested at ripeness and no significant differences in grain yield between Bt-maize and near-isogenic non-Bt varieties were found. These results were expected, as only Narbons harbours significant corn-borer populations. At Narbons, the number of Sesamia and Ostrinia corn-borer larvae were significantly lower in the Bt-maize than in a near-isogenic non-Bt variety and for Sesamia even less than in conventional varieties sprayed with pesticides to control corn-borer infestation. Here, Bt-maize produced a higher grain yield and grain size than a near-isogenic non-Bt variety or allowed a significant reduction in pesticide use. Concentrations of Cry1Ab in the Bt-varieties were sufficient to effectively control corn-borer larvae. In soil, Cry1Ab was close to the limit of detection and the protein did not accumulate in the soil year on year. 相似文献