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31.
Impact of macronutrient composition and palatability in wet diets on food selection in cats
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F. Salaun G. Blanchard L. Le Paih F. Roberti C. Niceron 《Journal of animal physiology and animal nutrition》2017,101(2):320-328
Cats are obligate carnivores adapted to high‐protein diets, but are commonly fed diets rich in carbohydrate. The aim of this study was to examine the food intake choices of cats when diets with different protein and carbohydrate contents were offered. Thirty‐nine cats participated in voluntary dietary intake studies. Four foods were formulated to provide between 24% and 53% of metabolizable energy as protein, between 43% and 11% as carbohydrate and holding dietary fat constant with a contribution of approximately 36%. Foods were offered either singly to evaluate voluntary food intake or in pairs to compare food intake between pairs of diets. Cats regulated their macronutrient intake to attain an overall diet composition that provided 53% of metabolizable energy as protein, 11% as carbohydrate and 36% as fat. The protein contribution corresponded to approximately 6 g of protein/kg body weight/day. High‐protein/low‐carbohydrate diets were always eaten preferentially over low‐protein/high‐carbohydrate foods. When low‐protein/high‐carbohydrate diets were offered, cats limited their food intake to limit daily carbohydrate intake to less than 3 g of carbohydrate/kg body weight. This carbohydrate ceiling may limit protein and even energy intake when only low‐protein/high‐carbohydrate diets were offered. The inclusion of palatability enhancer in the diets increased food intake but did not change protein or carbohydrate intake patterns, indicating that macronutrient intake can be regulated regardless of the use of palatability enhancers in cats. We conclude that cats can discriminate between diets based on macronutrient composition and regulate their intake to maintain maximal protein intake but limit carbohydrate intake. 相似文献
32.
Mohammad Monirul Islam Eef Meerschman Timothy Saey Philippe De Smedt Ellen Van De Vijver Marc Van Meirvenne 《Precision Agriculture》2012,13(3):384-392
Every growing season, paddy fields are kept both flooded and drained for a significant period of time. As a consequence, these
soils develop distinct physico-chemical characteristics. For practical reasons, these soils are mostly sampled under dry conditions,
but the question arises how representative the results are for the wet growing conditions. Therefore, the apparent electrical
conductivity (ECa) of a 1.4 ha alluvial paddy field located in the Brahmaputra floodplain of Bangladesh was measured in both dry and wet conditions
by a sensing system using the electromagnetic induction sensor EM38, which does not require physical contact with the soil,
and compared both surveys. Due to the smooth water surface under wet conditions which ensured increased stability of the sensing
platform, the results of the survey showed considerably reduced micro-scale variability of ECa. Furthermore, the wet survey results more reliably furnished soil-related information mainly due to the absence of soil moisture
dynamics. The differences between ECa under wet and dry conditions were attributed to differences in soil texture, mainly the sand content variation having considerable
effect on soil moisture differences when flooded following drainage. Accordingly, the largest differences between ECa under wet and dry conditions were found in those parts of the field with a large sand content. Hence, the conclusion was
that an ECa survey on flooded fields has an added value to precision soil management. 相似文献
33.
A map of the interactome network of the metazoan C. elegans 总被引:1,自引:0,他引:1
Li S Armstrong CM Bertin N Ge H Milstein S Boxem M Vidalain PO Han JD Chesneau A Hao T Goldberg DS Li N Martinez M Rual JF Lamesch P Xu L Tewari M Wong SL Zhang LV Berriz GF Jacotot L Vaglio P Reboul J Hirozane-Kishikawa T Li Q Gabel HW Elewa A Baumgartner B Rose DJ Yu H Bosak S Sequerra R Fraser A Mango SE Saxton WM Strome S Van Den Heuvel S Piano F Vandenhaute J Sardet C Gerstein M Doucette-Stamm L Gunsalus KC Harper JW Cusick ME Roth FP Hill DE Vidal M 《Science (New York, N.Y.)》2004,303(5657):540-543
34.
Michel E Baglin A Auvergne M Catala C Samadi R Baudin F Appourchaux T Barban C Weiss WW Berthomieu G Boumier P Dupret MA Garcia RA Fridlund M Garrido R Goupil MJ Kjeldsen H Lebreton Y Mosser B Grotsch-Noels A Janot-Pacheco E Provost J Roxburgh IW Thoul A Toutain T Tiphène D Turck-Chieze S Vauclair SD Vauclair GP Aerts C Alecian G Ballot J Charpinet S Hubert AM Lignières F Mathias P Monteiro MJ Neiner C Poretti E de Medeiros JR Ribas I Rieutord ML Cortés TR Zwintz K 《Science (New York, N.Y.)》2008,322(5901):558-560
Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars. 相似文献
35.
Denis M Henrique E Chidaine B Tircot A Bougeard S Fravalo P 《Veterinary microbiology》2011,154(1-2):163-170
Sows have been identified as a source of Campylobacter contamination in piglets. We carried out a one-year study, in 2008, at 53 farrow-to-finish farms in Brittany, France, to determine the proportion of sows excreting Campylobacter. We also determined the genotypes of the Campylobacter isolates. Moreover, Generalized Estimating Equations including repeated effects were used to assess the association between management practices and farm characteristics, and risk of Campylobacter shedding by sows. Per farm, 10 feces samples from sows were collected from selected sites (maternity, service area, gestation area) on the farms. Campylobacter isolates were identified by PCR and typed by PFGE. Campylobacter was detected in 25.1% of the 530 samples from sows, and 67% of the 53 pig farms had at least one positive sample (of 10 taken). All the Campylobacter isolates belonged to the Campylobacter coli species. They displayed a very high level of genetic diversity, also inside farms and few genotypes were common to several farms. Warmer months, large farms, and individual housing for sows were identified as risk indicators of Campylobacter shedding by sows. A short delay between sampling and treatment of the samples should be considered, to improve the detection of the bacterium in the feces samples. 相似文献
36.
37.
Emila Akroume Bernd Zeller Marc Buée Philippe Santenoise Laurent Saint-André 《Annals of Forest Science》2016,73(4):1005-1013
Key message
Near- and mid-infrared spectroscopy allows for the detection of local patterns of forest soil properties. In combination with dendrometric data, it may be used as a prospective tool for determining soil heterogeneity before setting up long-term forest monitoring experiments.Context
Forest soils and stands generally exhibit higher spatial heterogeneity than other terrestrial ecosystems. This variability needs be taken into account before setting up long-term forest monitoring experiments to avoid multiple interactions between local heterogeneity and the factors tested in the experiment.Aims
We hypothesized that raw near- and mid-infrared spectra can be used as an integrated proxy of a large set of soil properties. The use of this method, in combination with dendrometric data, should provide a quick and cost-effective tool for optimizing the design of experimental forest sites.Methods
We assessed the local soil heterogeneity at 11 experimental sites in oak and beech stands, which belong to a new forest long-term ecological research (LTER) network. We used near- and mid-infrared spectroscopy in soil and litter samples. The spectra were subjected to principal components analyses (PCA) to determine the intra-site variability of the soil and litter layers.Results
Based on mapped PCA coordinates and basic dendrometric data, it was possible to design the experiment and minimize the interactions between the treatment layout and the tested variables. The method was validated with chemical analyses of the soil. No interaction was detected at the set-up of the experiment between the treatment layout and chemical soil properties (C, N, C/N ratio, pH, CEC, Al, Mg, P2O5, Fe, Mn, Na, and K).Conclusion
Near-infrared (NIR) and mid-infrared (MIR) spectroscopy is a useful tool for characterizing the overall heterogeneity of soil chemical properties. It can be used without any preliminary calibration. In combination with dendrometric data, it provides a reliable method for optimizing LTER plots in different types of ecosystems.38.
39.
Philippe C. Baveye 《European Journal of Soil Science》2021,72(4):1924-1927
40.
Small-scale heterogeneity in carbon dioxide, nitrous oxide and methane production from aggregates of a cultivated sandy-loam soil 总被引:2,自引:0,他引:2
Benjamin K. Sey Ameur M. Manceur Joann K. Whalen Edward G. Gregorich Philippe Rochette 《Soil biology & biochemistry》2008,40(9):2468
Spatial variability in carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) emissions from soil is related to the distribution of microsites where these gases are produced. Porous soil aggregates may possess aerobic and anaerobic microsites, depending on the water content of pores. The purpose of this study was to determine how production of CO2, N2O and CH4 was affected by aggregate size and soil water content. An air-dry sandy loam soil was sieved to generate three aggregate fractions (<0.25 mm, 0.25–2 mm and 2–6 mm) and bulk soil (<2 mm). Aggregate fractions and bulk soil were moistened (60% water-filled pore space, WFPS) and pre-incubated to restore microbial activity, then gradually dried or moistened to 20%, 40%, 60% or 80% WFPS and incubated at 25 °C for 48 h. Soil respiration peaked at 40% WFPS, presumably because this was the optimum level for heterotrophic microorganisms, and at 80% WFPS, which corresponded to the peak N2O production. More CO2 was produced by microaggregates (<0.25 mm) than macroaggregate (>0.25 mm) fractions. Incubation of aggregate fractions and soil at 80% WFPS with acetylene (10 Pa and 10 kPa) and without acetylene showed that denitrification was responsible for 95% of N2O production from microaggregates, while nitrification accounted for 97–99% of the N2O produced by macroaggregates and bulk soil. This suggests that oxygen (O2) diffusion into and around microaggregates was constrained, whereas macroaggregates remained aerobic at 80% WFPS. Methane consumption and production were measured in aggregates, reaching 1.1–6.4 ng CH4–C kg−1 soil h−1 as aggregate fractions and soil became wetter. For the sandy-loam soil studied, we conclude that nitrification in aerobic microsites contributed importantly to total N2O production, even when the soil water content permitted denitrification and CH4 production in anaerobic microsites. The relevance of these findings to microbial processes controlling N2O production at the field scale remains to be confirmed. 相似文献