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Comfy’Pack : Assessing urban microclimate conditions and outdoor thermal comfort at pedestrian scale
No full textInternational audienceHow does urban space shape small-scale pedestrian thermal environments in the context of intense heat? To answer this research question, various mobile sensing techniques are proposed recently. However, the assessment of thermal environments at pedestrian level is complex because of physical urban heterogeneity, highly variable microclimate conditions and dynamically changing environmental factors. Therefore, high spatio-temporal resolution data is needed, which implies adapted sampling frequency, low sensor inertia and suitable data post processing methods.In this context, this work aims to present the portable meteorological measuring prototype, Comfy’PACK (Comfort Pedestrian Assessment of CitywalKs), to improve microclimate and pedestrian thermal comfort zoning in a dynamically changing physical urban environment. The wearable device consists of air temperature, humidity, solar radiation, wind speed and mean radiant temperature sensors, a GPS and a thermal camera. The experimental site is an identified future de-sealing site in the city of Nantes (France), aiming to improve local outdoor thermal comfort. After a detailed physical characterisation of pedestrian pathways on site, mobile measures are repeated over several days, investigating transitions between different thermal ambiances. In this work we present the prototypes’ performances and its first application to an urban case study, evaluating small scale microclimate and thermal comfort conditions for pedestrians in relation with urban heterogeneity. Thermal comfort indicators are calculated, questioning their pertinence within various thermal environmental contexts. Data mapping will allow establishing a more detailed microclimate comfort zone classification. As part of the French research project PERMEPOLIS the findings will support the methodological development of soil de-sealing strategies and identification of alternative cool walking path in the urban space
Apports et limites des démarches participatives et de coconception pour améliorer le bien-être de l’animal en élevage
No full textInternational audienceImproving the welfare of farm animals, which is essential for the sustainability of livestock farming, raises questions and sometimes heated debates, in particular among livestock farming professionals, researchers, public authorities and citizens. Participatory and co-design approaches, which aim to bring together a wide range of stakeholders with sometimes divergent positions, to develop knowledge and innovative solutions, are particularly relevant in the field of animal welfare. The emergence of a consensus around a problem, defined and understood by all the stakeholders, and a solution can only be achieved within a framework of trust and mutual listening, for which the facilitator of the process will be the guarantor, and which requires time. Through six illustrative projects, significant benefits have been identified, whether in terms of awareness and open-mindedness or in terms of proposing operational solutions. The challenges lie in assessing the impact of the solutions developed, in terms of real improvements in animal welfare, and in disseminating these solutions in the field, considering the economic and social dimensions in which they are embedded.L’amélioration du bien-être des animaux en élevage, essentielle pour la durabilité de l'élevage, suscite des questionnements et des débats, parfois vifs, notamment parmi les professionnels de l’élevage, la recherche, les pouvoirs publics et les citoyens. Les démarches participatives et de coconception qui visent à faire coopérer de multiples acteurs, aux positions parfois divergentes, permettent l’interconnaissance, interrogent le besoin de nouvelles connaissances et peuvent également permettre la production collective de nouvelles connaissances. Faire émerger des connaissances et des solutions innovantes est particulièrement pertinent dans le domaine du bien-être animal. L’émergence d’un consensus autour d’une problématique, définie et comprise par tous les acteurs, puis d’une solution, nécessite une coopération dans un cadre de confiance et d’écoute mutuelles, dont l’animateur du processus sera le garant et nécessite du temps. Au travers de six projets illustratifs, des bénéfices notables ont été recensés, qu’ils soient de l’ordre de la prise de conscience et de l’ouverture d’esprit ou bien de la proposition de solutions opérationnelles. Les enjeux résident dans l’évaluation des impacts des solutions coconstruites en matière d’amélioration réelle du bien-être des animaux, ainsi que dans la diffusion des solutions sur le terrain, en tenant compte des dimensions économiques et sociales dans lesquelles elles s’inscrivent
The protein ingredient quality of infant formula influences colonic physiology and microbiota and the serum metabolomic profile in neonatal mini-piglets
No full textPig Physiology and Phenotyping Experimental Facilit,doi: 10.15454/1.5573932732039927E12International audienceDespite the WHO recommendations in favor of breastfeeding, most infants receive infant formulas (IFs), which are complex matrices involving numerous ingredients and processing steps. Our aim was to understand the impact of the quality of the protein ingredient in IFs on gut microbiota and physiology, blood metabolites and brain gene expression. Three IFs were produced using whey proteins (WPs) from cheese whey (IF-A) or ideal whey (IFs-C and -D) and caseins, either in a micellar form (IFs-A and -C) or partly in a non-micellar form (IF-D). Twenty-four Yucatan minipiglets received one of the IFs from 2- to 21-days of age. The piglets were then euthanized 84 min postprandially. Blood, ileal and colonic digesta and tissues, the liver and the hypothalamus were sampled. Gut microbiota composition and activity, the expression of intestinal and brain genes involved in barrier, immune, endocrine, nutrient carrier and neuronal functions and serum metabolite levels were determined. Intestinal paracellular permeability was assessed with an ex vivo Ussing chamber. The data were analyzed using multifactorial and univariate analyses. The colon was the main site to be physiologically affected by the quality of the dairy protein ingredients used in IFs. Colonic paracellular permeability was significantly higher in IF-D-fed piglets than in those receiving IFs-A and -C, in line with the expression of genes encoding tight junction proteins (OCLN, CLDN3 and CLDN4). IF-D up-regulated the colonic expression of genes involved in the immune function (SOCS3, PIGR and TNFα) when compared to IF-A. Although intestinal α- and β-diversities did not significantly differ among IFs, some specific differences were observed, such as the abundances of Campylobacterota phylum and Bacteroides genera and fecal butyrate production, which were increased with IFs-C and -D versus IF-A. The kynurenine pathway was favored in piglets fed IF-D compared to IF-A, based on colonic gene expression and serum metabolites. In addition, levels of some serum metabolites, particularly putrescine, spermidine and spermine, were higher in piglets fed IF-D than IFs-A and -C. Overall, IF-D, which combined ideal WPs and some non-micellar caseins, appeared to differ most from IF-A in terms of its physiological consequences, suggesting that both WP and casein ingredient quality may mediate the physiological properties of IFs, probably through changes to the colonic microbiota composition and activity
WAIT4 – un projet de recherche alliant technologies numériques et IA pour évaluer des indicateurs pertinents de bien-être pour des animaux confrontés aux défis des transitions agroécologique et climatique
No full textNational audienceLe projet WAIT4 exploite les opportunités offertes par les technologies numériques pour mesurer différentes composantes du bien-être animal en temps réel ; il met en œuvre des approches d’IA pour intégrer les données hétérogènes, par nature et en temporalité, qui sont ainsi collectées. L’objectif est de définir de nouveaux indicateurs et la fréquence pertinente avec laquelle les mesurer, afin d’identifier les variations du bien-être de l’animal. Différentes espèces (porcins, petits et gros ruminants), en systèmes conventionnels, biologiques ou agropastoraux, et sous des climats contrastés sont abordées. L’ambition est de détecter des déviations précoces des changements de bien-être et de santé en réponse à des changements de pratiques et face aux aléas climatiques. Le projet met en œuvre des actions concertées associant des d'instituts français de recherche (INRAE, CEA, INRIA, INSA), et un dialogue avec les porteurs d’enjeux grâce à l’appui du LIT Ouesterel pour faciliter l’appropriation et la diffusion des résultats. Le projet WAIT4 (2023-2027), coordonné par INRAE, est financé par France 2030 dans le cadre du PEPR Agroécologie et Numérique
Genetic relationships between milk lactose content, lactosaemia, udder health and metabolic status in dairy cows
No full textInternational audienceMammary inflammation in dairy cows has an adverse effect on the mammary epithelium, with an increase in lactosaemia (blood lactose, BL) and a decrease in milk lactose (ML) content. On the other hand, the high glucose demand for lactose synthesis during lactation can lead to metabolic disorders. The objectives of the present study are to assess the genetic link between lactose contents and the udder health and metabolic status of dairy cows. We investigated genetic associations between ML, BL, and indicators of udder health (Somatic Cell Score, SCS) and metabolic status (non-esterified fatty acids (NEFAs), beta-hydroxybutyrate (BHB), glucose, and urea) at different stages of lactation. The study is based on 3197 test-day records collected from 662 Holstein, Normande and crossbred cows raised at the INRAE experimental farm of Le Pin (doi: 10.15454/1.5483257052131956E12). We estimated heritability and genetic correlations by applying multi-trait animal mixed models based on test-day records, including a random permanent environmental effect and non-genetic fixed effects. Our findings reveal moderate heritability estimates for blood metabolites (0.12, 0.14, 0.17, 0.19, and 0.25, for urea, BL, BHB, NEFAs, and glucose, respectively) and for ML (0.28). Genetic correlations between blood metabolites ranged from -0.62 (BL and glucose) to 0.28 (BL and BHB), while genetic correlations between ML and blood metabolites varied from -0.40 (with BL) to 0.43 (with glucose). ML and BL, negatively correlated, presented a negative (-0.24) and positive (0.61) genetic correlation with SCS, respectively. Standard errors varied from 0.04 to 0.07 for heritability estimates and from 0.18 to 0.26 for genetic correlations. These results support the hypothesis of a genetic link between lactose metabolism and cow health, suggesting that milk and blood lactose may serve as valuable indicators of udder health and metabolic status, with potential applications for genetic selection and management practices in dairy herds
From research to practice: the genesis of a guide to help reduce urban soils sealing
No full textInternational audienceSoil sealing is a very real and growing phenomenon in our cities. While soil sealing has historically been justified by health issues, it also responds to very practical expectations in terms of mobility and housing, in line with the massive urbanisation. Paradoxically, Ekranic Technosols, which are the living environment of most of the population, have long been neglected by research. Yet they are closely linked to major environmental issues. Soil sealing has serious consequences, for example in terms of loss of biodiversity, increased flooding and development of urban heat islands. The French multidisciplinary and multi-stakeholder research project DESSERT had the aim of gaining a better understanding of the functioning and capacity of urban soils to provide ecosystem services before and after desealing. Based on both an inventory of sealing practices and laboratory and field experimental approaches, the aim was also to describe sealing operations and their support from an operational perspective. A guide is the result of the collaboration between partners. It provides a scientifically based aid to the design of desealing operations, as well as explaining the various benefits of desealing. In addition to describing the steps and documents required to carry out these operations the guide highlights their fundamental role in achieving cities with a high level of ecological functions and ecosystem services. Illustrated with numerous examples, the guide is aimed at landscape designers and urban planners but is also accessible to anyone wishing to (re)discover urban soils
Inducible MdAGG lectins in apple immunity toward Fire Blight: CRISPR/Cas9 validation and their potential for intragenesis approaches
No full textInternational audienceFire blight, caused by the bacterium Erwinia amylovora, represents a significant threat to apple (Malus domestica) production. Currently, only a limited number of genes effectively involved in resistance to E. amylovora have been identified.Seeking new resistance candidates, we focused on a multigene family encoding amaranthinlike lectins, which are highly upregulated following chemical elicitation by acibenzolar-Smethyl (ASM). These lectins are believed to contribute to downstream defense by promoting bacterial aggregation, which led to their designation as Malus domestica agglutinins (MdAGG).When loss-of-function editions were introduced into MdAGG genes, the plant's ability to mount a fully effective defense response against fire blight upon ASM treatment was compromised, confirming the role of MdAGGs in fire blight resistance. Next, we coupled the pPPO16 promoter, endogenous to apple and known to be rapidly induced during E. amylovora infection, with the coding sequence of MdAGG10 to create apple lines with fire blight-inducible MdAGG10 expression. Early MdAGG10 expression in these lines significantly improved resistance to fire blight, and an additional ASM treatment further enhanced this resistance.In summary, we conclude that MdAGGs act as defense genes whose timely expression can provide effective resistance against E. amylovora.</p
Evaluating the potential of Sentinel-2 data to assess the coarse fragment cover of the soil surface within a Spanish vineyard
No full textInternational audienceThe presence of coarse fragments (CF) on the soil surface is a critical factor influencing the assessment of key soil properties such as hydraulic conductivity and C stocks, as well as erosion processes [1–3]. This study investigates the potential of Sentinel-2 (S2) data to estimate soil surface CF cover for an 82-ha trellis-trained vineyard (Burgos, Spain), with ~3 m-inter-row spacing. CF cover (%) was estimated using the point-count method via SamplePoint [4], based on nadir photos taken ~1 m height above ground level, at 60 points repeatedly during three field campaigns. Based on two S2 time series (Jan 2023–Feb 2024 and Jan–Apr 2023 (vine dormancy)), six spectral indices computed within a 30 m-buffer were clustered through hierarchical agglomerative clustering (HAC) and principal component analysis (PCA), which led to the selection of the Non-photosynthetic vegetation soil separation index (NSSI). Assessment of NSSI relevance relied on correlating NSSI values, extracted from S2 images closest to field campaign dates, with the average CF cover, with and without applying an NDVI threshold of 0.4. A Random Forest algorithm was then used to predict CF cover, with 70% calibration 30% validation split repeated over three random iterations. Two approaches were tested, with and without NDVI threshold: (1) S2 bands only, and (2) S2 bands + NSSI + NDVI. NSSI was moderately correlated with CF cover (R² = 0.47–0.60), while best correlated with NDVI threshold (R² = 0.48–0.77). Calibration performance was good across all models (R²>0.6; RMSE<16.75%; RPD>1.62; RPIQ>2.23), even though validation results were variable. NDVI thresholding alone did not improve validation, but adding NSSI+NDVI as predictors enhanced validation accuracy. The best performance was obtained by combining data from all campaigns using S2 bands + NSSI + NDVI without any NDVI threshold (R² = 0.42; RMSE = 17.53%; RPD = 1.55; RPIQ = 2.05)
The impact of chronic heat stress on DNA methylation and gene expression in laying hens
No full textInternational audienceEnvironmental stressors, such as heat, can induce epigenetic modifications, including changes in DNA methylation, which may influence gene expression and contribute to phenotypic variability. This study examined the effects of chronic heat stress on liver DNA methylation in laying hens and investigated whether these changes may mediate genes expression. We used Reduced Representation Bisulfite Sequencing (RRBS) for genome-wide, single-base resolution DNA methylation profiling to analyze patterns of heat-induced methylation variation. We used RNA sequencing (RNA-seq) data to analyze differential gene expression between control and heat stress hens. A total of four hundred NOVOgen commercial brown egg layers were housed in two temperature-controlled chambers (200 hens each) under thermo-neutral conditions (22°C). At 27 weeks of age, the temperature of one chamber was increased to 32°C for four weeks. Liver samples were collected at 31 weeks of age from 20 animals per group for RRBS and RNA-seq analyses. Differential methylation analysis identified 4824 DMC (Differentially Methylated CpG sites) and 418 DMR (Differentially Methylated Regions). The majority of the affected CpGs were hypermethylated and distributed across most chromosomes. In total, 1120 genes were associated with DMCs. The transcriptomic analysis revealed 3578 differentially expressed protein coding genes (DEG) with 1747 genes upregulated and 1831 downregulated under heat stress. Comparing these two gene lists, we found that 269 of these DEGs harbored DMCs in promoter, exon, or intron regions. Interestingly, the large majority of these were upregulated and 27 of them were transcription factors. The functional enrichment analysis of these genes highlighted an enrichment for biological processes and molecular functions related to regulation of transcription, RNA metabolic process, and DNA-binding