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Predicting in vivo protein digestibility from ingredient composition and in vitro digestion
No full textInternational audienceBackground and objectives. The nutritional quality of proteins depends on their indispensable amino acid profile and their digestibility. Accurate measurement of protein digestibility requires in vivo experimentation, which presents several constraints. In vitro digestion models have been developed, but presently, none of them can provide a totally reliable assessment of protein digestibility. An alternative approach, the subject of this study, could be to model protein digestibility on the basis of in vitro digestion data and/or readily available physicochemical characteristics of protein sources.Methods. a dataset of 47 individuals, each corresponding to a specific plant protein ingredient in a given form (seed, powder, or isolate, with or without processing), was created. Each individual was characterized by variables measured after in vitro digestion using the Infogest protocol (proteolysis degree, % soluble nitrogen), compositional traits (content of protein, lipid, carbohydrate, starch, fiber, and amino acid profile), and in vivo true N digestibility (ileal or fecal). PCA and hierarchical clustering (HAC) were applied, followed by multiple linear regression to model in vivo digestibility, with missing data handled.Results. The PCA did not reveal significant correlations between in vivo digestibility and characteristics derived from in vitro digestibility, nor with compositional traits, except for fiber content, which showed an inverse correlation (r² = -0.73) with in vivo digestibility. The HAC identified three clusters of individuals: those with low in vivo and in vitro digestibility, those poorly digestible in vivo, and those highly digestible in vivo and in vitro. The latter cluster was characterized by the presence of ingredients that had undergone significant processing, while the former included various forms of chia. Several highly significant (p-value<10 -6 ) regression models were established, with the best performing (r²=0.777, p-value=4.8e-08) modeling in vivo digestibility from the degree of proteolysis measured in vitro, content of fibers and protein content in Arg, His, Ile, Lys and Pro.Conclusions. This preliminary study shows potential for predicting in vivo digestibility of plant protein ingredients using easily accessible measurements, which could reduce the need for in vivo experiments. However, further validation is required, both by expanding the dataset with more diverse, well-characterized ingredients and by using cross-validation.These approaches are currently being explored.</p
EFFICIENCE D’UTILISATION D’ENGRAIS ORGANIQUES PAR LES PLANTES : INNOVATION D’UN ÉTIQUETAGE COMMERCIAL FERTILISANT
No full textInternational audienceLes producteurs et consommateurs expriment de plus en plus une préoccupation vis-à-vis de la qualité desproduits végétaux qu’ils se procurent et qu’ils consomment, et de l'impact de la production végétale surl'environnement. A l’heure du consommer mieux et de la gouvernance des communs, une transitionagroécologique majeure s’est opérée ces dernières années. Dans la filière de l’horticulture, la fertilisationorganique et le développement de supports de culture à partir de matières organiques renouvelables est aucœur des préoccupations (Burnett et al., 2016). A la différence des engrais minéraux ou engrais “retard” quisont presque immédiatement assimilables par les plantes, les engrais organiques doivent d’abord subir unephase de minéralisation, processus biologique réalisé par les communautés microbiennes présentes dans lessupports de plantatio
Insect Pollinators (Hymenoptera: Aculeata) Diversity on Aromatic and Medicinal Plants from Tunisia
No full textInternational audienceThis study investigates the diversity of hymenopteran aculeate fauna associated with aromatic and medicinal plants from Tunisia. In terms of taxonomic diversity, 68 species belonging to 36 genera, four superfamilies and 12 families are identified. The most represented genera are Andrena and Hylaeus, accounting for 26.51% and 17.15% of the total abundance, respectively. Themost species-rich are Andrena (11 species), Lasioglossum (6 species) and Hylaeus (5 species). Individuals captured on sweet fennel account for almost 60% of the total sample, confirming its strong attractiveness to aculeate Hymenoptera. Wild solitary bees (Andrenidae, Halictidae and Colletidae) are the most collected, with Halictidae favoring wild fennel and Colletidae favoringsweet fennel. The Shannon diversity index (H’), MAPs have the maximum value, suggesting that MAPs tend to support slightly more diverse and evenly distributed communities, in contrast to wild fennel, which is more strongly dominated by the genera Hylaeus, Andrena, Nomioides and st, hymenopteran pollinators are most attracted to all studied plants, with a preference for wild and sweet fennels. These findings suggest that fennel and other MAPs could be integrated into management programs for pollination-dependent crops such as cucurbits and Tunisian almonds
OneWater Data: towards a national FAIR water data platform and community
No full textInternational audienceAs part of the FAIR Water Data platform, we explain the importance of contributing to the co-construction of an ecosystem of FAIR services related to water.To achieve this goal, we present the general FAIR Factory method and illustrate it with various examples
Evolution of perceptions of French high school students on livestock farming between 2014 and 2025
No full textInternational audienceIn many Western countries, people are increasingly disconnected with farms realities, and their knowledge about agricultural practices is steadily declining, while their expectations about production, animal welfare and environmental impact are rising. In 2014, we conducted a survey on the perceptions and concerns about livestock farming on 1,083 French high school students. As significant societal and environmental changes occurred since then, a similar survey was undertaken in January 2025, among 503 French high school students. A similar questionnaire to the 2014 one was used, including closed and open-ended questions to evaluate the perceptions, consumption habits, knowledge, and interest in livestock farming and practices of these young people. From 2014 to 2025, the percentage of students who experienced contact with farm animals or visited a farm decreased by 22% and 15%, respectively, meaning that only 25% of them have been in contact with farm animals 2025. This might be due to a lower proportion of students enrolled in agricultural studies in 2025’s sample, as well as stricter biosecurity measures that have restricted public access to farms. The results also showed that in 2025, 36% of students had a positive perception of livestock farming, compared to 44% in 2014. Students’ main concerns regarding livestock farming remained consistent over time, with animal welfare (87%), environmental impacts (57%) and health crises (22%) being the most important in 2025. Over 90% of the students considered that livestock production is of importance in France, especially for its role in providing local food. Information regarding livestock farming mainly originated from social networks and TV news, and many students indicated that they would like to be better informed, mainly via professional interventions and social networks. It was concluded that, despite changing contexts, the main concerns of higher school students still remained similar from 2014 to 2025, and they were still in favour of preserving livestock farming in France
A comparison of natural pest control measurement methods: which indicators do we need to quantify predation?
No full textInternational audienceUnderstanding the conditions favourable to the natural regulation of pest insects and adapting management strategies based on this ecosystem service depend entirely on reliable and effective methods of measuring the intensity of predation (the number of preys killed by a predator per unit of time). However, it remains difficult to quantify predation in the field while estimating the specific contributions of a diversity of coexisting predators. We reviewed the available methods for estimating pest predation, distinguishing between direct or indirect measures (e.g., video recording or DNA-based testing) and inference methods (e.g., estimating predation rates from pest population dynamics) and more general proxies (e.g., predator diversity). We analysed the quantitative, qualitative and semi-quantitative information provided by these methods, from the individual hunter to the predator community, and discussed their field of application, merits and biases. A particular development based on the techniques of molecular detection of prey consumed by predators consists of converting the qualitative information obtained into a quantitative estimate of the predation rate. This also comes with a set of limitations.None of the methods considered on its own allows for a reliable estimate of the intensity of pest predation by a community of predators while estimating the contribution of each predator species. Fortunately, combining molecular detection data (PCR like) from field-caught predators with estimated abundances of predator species in the field, the most frequently measured variable but which has a noisy correlation with pest predation, offers a promising and elegant way of meeting the challenge. We show how an indicator that aggregates the predation intensities estimated simultaneously for a set of predatory species can be constructed using this approach and provide a new tool for quantifying biological pest control
Analyse nomenclaturale et typification du lotier de Jordan
No full textInternational audienceBased on a detailed nomenclatural analysis, we conclude that the combination Lotus jordanii Coulot, Rabaute & J.-M. Tison is valid for designating the Mediterranean coastal Lotus, initially named Dorycnium gracile by Alexis Jordan, which has been the subject of several treatments since that date.We also designate the lectotyp.À l’appui d’une analyse nomenclaturale détaillée, nous concluons sur la validité de la combinaison Lotus jordanii Coulot, Rabaute & J.-M. Tison pour désigner le lotier du littoral méditerranéen, appelé initialement Dorycnium gracile par Alexis Jordan, et qui a fait l’objet de plusieurs traitements depuiscette date. Nous en désignons également le lectotype
Spatial prediction of soil properties using Sentinel-2 temporal mosaics of non-vegetated soils in a semi-arid region: A comparative evaluation of Google Earth Engine and THEIA platforms in Sminja
No full textInternational audienceThis study investigates the potential of Sentinel-2 (S2) temporal mosaics (TM) of non-vegetated soils for enhancing soil property mapping in the semi-arid Sminja Plain, Tunisia (480 km²). Utilising data from 2019 to 2023 across all seasons (autumn, spring, summer, and winter), we generated TM through the Google Earth Engine (GEE) and THEIA platforms. This comparative evaluation highlighted the importance of platform selection and seasonal considerations in remote sensing-based soil property predictions. Non-vegetated soils were isolated using thresholds of NDVI < 0.35 and NBR2 < 0.09 to maximise non-vegetated soil extraction. Key soil propertiesanalysed through a dataset of 215 sample locations regularly spread over the area included electrical conductivity (EC), soil organic carbon (SOC), pH, base saturation (BS), granulometric fractions, and soil moisture content. Random forest (RF) models with K-fold cross-validation assessed the predictive performance, evaluated using RMSE, RPD, and RPIQ metrics. Results indicate that both GEE and THEIA platforms effectively predicted (with THEIA having a very slight edge) most of the soil properties (SOC, CaCO₃, Ca, base saturation, granulometric fractions, and soil moisture content) with RPIQ values exceeding 1.7, while predictions for pH, EC, K, Na, and P₂O₅ were poorly reliable with RPIQ < 0.8. This pinpointed the limitations of the generated RF models for certain soil properties in such environments. Seasonal variations slightly influenced model accuracy, underscoring the importance of platform selection and temporal considerations in remote sensing-based soil property prediction. These findings offer valuable insights for sustainable land management and agricultural planning in semi-arid regions
Chapter 4 -Fish growth: Patterns and modeling
No full textInternational audienceSize matters in many facets of fish ecology and fisheries production. Growth is a fundamental biological process that is closely tied to protein metabolism. Different ways of describing individual fish growth can be identified, requiring careful selection of time scales and measurement of growth currency in relation to other factors. Acquiring biometric data across age points within a population or individual is crucial for accurate growth measurements, requiring careful consideration of essential conditions. Measuring growth can be based on various methods (direct measurements, size-composition data, sclerochronology, biochemical growth proxies, or epigenetic aging) and various growth models can be used to describe the relationship between fish length and age. The von Bertalanffy growth function (VBGF) is the most famous and widely used analytical method. However, while such growth models are mainly empirical and phenomenological, they are based on bioenergetics assumptions, considering growth as a product of the balance between anabolism and catabolism. Several authors have developed bioenergetics theoretical frameworks to better describe physiological processes involved in growth and how factors like diet composition, feeding rates, and metabolic efficiency influence the growth potential of marine fish. These frameworks can also help predict responses to environmental changes, such as shifts in prey availability and climate-induced habitat alterations
Acquisition pilotée par la donnée pour accélérer la microscopie point-à-point de type Brillouin
No full textInternational audienceWe propose a smart scanning protocol to speed up the acquisition of Brillouin microscopy. It is based on a bimodalimaging system. During a first pass, we use a full-field imaging modality (fluorescence or phase contrast) correlated with Brillouininformation to rapidly provide a global view of the scene. A segmentation of the region of interest of this scene is performed. Thepixels of this region of interest are then acquired with a local Brillouin probe via an online algorithm that auto-adaptively set thetime spent on each of them. We take advantage of recent work on the use of so-called essential pixels identified in the space ofFourier spectral phasors.Nous proposons un protocole de « smart scan », c'est-à-dire une acquisition pilotée par la donnée, pour accélérer l'acquisition de la microscopie Brillouin. Il est basé sur un système d'imagerie bimodale. Dans une première passe, nous utilisons une première modalité d'imagerie plein champ (fluorescence ici) correlée avec l'information Brillouin qui fournit rapidement une vue globale de la scène. Une segmentation de la région d'intérêt de cette scène est réalisée. Les pixels de la région d'intérêt sont ensuite acquis avec une sonde locale de type Brillouin via un algorithme en ligne qui ajuste de façon auto-adaptative le temps passé sur ces pixels. Nous mettons ici à profit des travaux récents sur l'usage des pixels dits essentiels identifiés dans l'espace des phaseurs spectraux de Fourier