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Identifying the critical life stage of a recruitment-driven decline in an exploited marine fish stock: The Bay of Biscay common sole
No full textInternational audienceIn the Bay of Biscay (BoB), the common sole (Solea solea) population supports a major commercial fishery. However, a decline in recruitment has been observed since the late 2000's, despite management measures that have lowered fishing mortality. This study investigates the decline in sole juvenile abundance in the BoB coastal and estuarine nursery grounds and compares recruitment trends among sole stocks across the Northeast Atlantic. The analysis of stock assessment products revealed that recruitment decline preceded and drove the subsequent decrease in the coming spawning stock biomass, with a two-year lag. Time series of juvenile abundance, estimated using habitat suitability models based on young fish survey data, showed a decreasing trend since the 2000's in four of the six main BoB nursery grounds, for juveniles at ages 0 and 1 year, in both spring and autumn. This decline in sole juvenile abundance shortly after metamorphosis indicates reduced settlement success in nursery habitats. Because this decline was observed across several nursery grounds from early juvenile stage, it suggests that changes in pelagic conditions may have impaired sole larval survival. Across the Northeast Atlantic, recruitment trends among sole stocks displayed no consistent latitudinal or spatial pattern, indicating population-specific responses to local factors
From Glasshouse to Field: Assessing Potato Variety Growth Consistency under Drought Conditions
No full textInternational audiencePotato, produced by Solanum tuberosum L., serves as a critical component in meeting the demands of food security. Drought is classified as the primary abiotic stressor affecting potato plants, leading to yield reductions from 30 to 61%, and even exceeding 75% some years in the most susceptible varieties. In this study, through nine trials implemented in fields and glasshouses, we evaluate the drought tolerance of 59 varieties, according to their tuber yield after periods of water shortage. Meanwhile, 29 plant growth traits have been measured to find common drought tolerance traits that enable the estimation of tuber yield, regardless of trial conditions. Among them, aboveground biomass production per plant in interaction with Harvest Index emerged as the most reliable predictor of tuber yield across all trials and water conditions, explaining between 89 and 93% of tuber mass variability. Different models were implemented to assess the accuracy of these findings and determine their applicability to other trials. We found that field trials predicted other field trials with high accuracy, between 87 and 94%. Additionally, glasshouse trials under control conditions (fully irrigated) accurately predicted tuber yield in field trials under drought conditions, achieving 85% accuracy. Furthermore, potato plants yielded twice as much in field trials compared to glasshouse trials, likely due to the higher night/day temperature differential in the field, as night temperatures were higher in the glasshouse soil type, or drought imposition. We hypothesise that by reducing night temperature in glasshouse trials, potato plants grown in glasshouses could be more representative of potato plants growing under field conditions, thereby enhancing tuber yield prediction
Stochastic simulations to optimize genomic selection for laying hens: impact of generation interval and genotyping in the context of extended laying period
No full textInternational audienceExtending the productive lifespan of laying hens is a key objective for sustainable egg production.Achieving this goal requires improving egg production and quality traits expressed late in life. Genomic selection offers opportunities to increase accuracy of selection for such traits, while shorter generation intervals can accelerate genetic progress. However, both strategies may affect inbreeding, and their combined impact in the context of extended laying cycles has not yet been quantified. Stochastic simulations were performed to evaluate seven breeding programs for layers, based on real genotype data and six quantitative traits (egg weight, egg shell strength, and laying rate, each at 60 and 90 weeks). Programs differed by generation interval (L, 60, 45, or 30 weeks) and two selection method were applied to each scenario: single-step GBLUP using male genotypes (ssGBLUPm), or single-step GBLUP using both male and female genotypes (ssGBLUPmf). A control PBLUP based scenario with a 60 weeks L was also performed. Each scenario was replicated 30 times, and results were compared for annual genetic gain (∆G), prediction accuracy (r), and inbreeding rate (∆F). Genomic evaluations using a generation interval of 60 weeks improved both ∆G and ∆F, especially when both sexes were genotyped. Reducing the generation interval to 30 weeks maximized ∆G (up to 1.17 SD/year) but increased ∆F above 1%/year. Overlapping generation schemes (45-week interval) provided an intermediate outcome, improving ∆G compared with conventional 60-week generation interval schemes while limiting ∆F compared with 30-week generation interval schemes. Including female genotypes was particularly beneficial for laterecorded traits at 90 weeks, where accuracy increased by up to 38%. Shortening generation interval and implementing genomic selection substantially increased annual genetic gain, especially for persistency traits expressed late in life. However, these strategies also raised inbreeding, with overlapping generations offering a valuable compromise. Full genotyping of both sexes enhance
Enabling cross-sectoral transformation for coastal climate adaptation in Europe: Four directions for interdisciplinary efforts
No full textInternational audienceCoastal areas in Europe are of immense value – not only to their residents but also to communities further inland. At the same time, they are particularly vulnerable to the impacts of climate change. The current pace of coastal climate adaptation remains slow, constrained by underfunding and the fragmented, sectoral nature of many initiatives. This calls for radically new yet practical approaches. In this perspective, a group of European researchers from diverse disciplines explores what cross-sectoral transformation could mean in the context of coastal climate adaptation. Drawing on expertise in environmental science, spatial planning, law, ecology, health, and tourism, we propose four directions for interdisciplinary research to enable such transformation: (1) developing dynamic and holistic understandings of climate impacts and adaptation responses; (2) establishing shared adaptation objectives and priorities across sectors; (3) promoting ecosystem-based development; and (4) adapting legal and institutional systems to support integration and flexibility. We invite scholars and practitioners to engage with these interdependent directions to advance adaptation efforts for European coasts
How the Covid-19 pandemic has changed the behaviour of consumers of fisheries and aquaculture products (FAP) in France
No full textInternational audienceA year after the pandemic, we surveyed 1268 French FAP consumers in April 2021 to evaluate if the crisis had led to more sustainable consumption patterns by giving priority to fresh seafood from local circuits. We also match those results with a study prior to the Covid-19 to estimate the impact of the crisis on the perception of FAP. For more than 50% of consumers, the Covid-19 crisis did not lead to change in their FAP consumption and we found a very small proportion of consumers who increased their purchases of fresh FAP and favoured short channels during and after the Covid-19 crisis. We demonstrate that pre-Covid-19 characteristics and attitudes are important explanatory factors for behaviour during the crisis. Big consumers of fresh FAP and consumers with a positive image of the health benefits of seafood were more likely to have increased their consumption of fresh FAP. Similarly, people who were used to consuming FAP away from home instead consumed FAP at home during the crisis and after. The results also suggest that consumers tended to perceive FAP as more expensive after the Covid-19, a major obstacle to the emergence of more sustainable consumption behaviour in this sector
Optimizing phosphorus input and straw return enhances soil health: Insights into microbial functional gene indicators in Solanum lycopersicum
No full textInternational audienceIntensive greenhouse vegetable production plays a crucial role in meeting food demand but is often associated with excessive fertilizer inputs and continuous monoculture, leading to soil degradation, microbial imbalance, and increased incidence of soilborne diseases (Li et al., 2014, Ma et al., 2023, Sun et al., 2025). In S. lycopersicum systems, root rot and yield loss are closely linked to soil health decline, and phosphorus (P) overuse is particularly problematic. The low use efficiency of applied P (only 10–20 % uptake by crops) and residual P accumulation not only waste resources but also elevate environmental risks (Almario et al., 2014, Chien et al., 2018, Kopittke et al., 2019, Zhao et al., 2022). With phosphate rock projected to be depleted by 2050, optimizing P management has become a priority for sustaining intensive agriculture (Rowe et al., 2016, Chanda et al., 2025, Gong et al., 2025, Wu et al., 2025). Although precision nutrient strategies integrating reduced N and P inputs have shown promise (Getahun et al., 2024, Liu et al., 2023a), few studies have systematically examined how nutrient reduction can sustain yield while alleviating soil health deterioration in high-input S. lycopersicum systems.Plants exhibit adaptive responses under P deficiency, including increased root length, secretion of organic acids, and recruitment of phosphate-solubilizing microbes that harbor functional genes such as phoD (alkaline phosphatase) and pqqC (pyrroloquinoline quinone synthase) (Fan et al., 2025). These mechanisms mobilize unavailable P and enhance plant uptake (Hu et al., 2025, Jarosch et al., 2015, Luo et al., 2019, Wen et al., 2019). Moderate P reduction has been reported to enrich these beneficial microbial communities while maintaining crop productivity (Cao et al., 2022, Liu et al., 2022, Wang et al., 2025). Similarly, straw return is recognized as a sustainable practice that increases soil organic matter, improves structure, and stimulates microbial activity and nutrient cycling (Bai et al., 2023, Fu et al., 2021, Li et al., 2023, Liu et al., 2023b). Long-term studies show that straw incorporation can raise P-use efficiency by more than 60 % when combined with inorganic fertilizer (Guo et al., 2018, Xiao et al., 2024, Wang et al., 2024, Wang et al., 2025). Straw-induced microbial shifts may also enhance beneficial taxa such as Pseudomonas and Streptomyces, which suppress soilborne pathogens (Ling et al., 2024, Zhang et al., 2024b, Wang et al., 2022). However, it remains unclear how the integration of P reduction and straw return influences nutrient-cycling and disease-suppressive genes in high-input greenhouse systems.Soil health evaluation frameworks have increasingly emphasized the need to incorporate biological indicators (Joos et al., 2023, Kruczyńska et al., 2023). Traditional assessments based largely on physical and chemical properties fail to capture the dynamic, process-driven roles of microbial communities (Rinot et al., 2019, Wade et al., 2022). Recent advances highlight microbial functional genes-including phoD, pqqC, and nitrogen-cycling genes (nirS, nosZ)- as sensitive and mechanistic indicators of microbial functional potential, soil multifunctionality, and ecosystem resilience (Creamer et al., 2022, Jia et al., 2025, Luo et al., 2019, Trivedi et al., 2016). Yet few studies have simultaneously quantified how reduced P fertilization and straw return regulate functional gene networks, soil multifunctionality, pathogen dynamics, and yield in intensive S. lycopersicum production.To address this gap, we conducted a long-term field experiment in a facility-grown S. lycopersicum system, testing four P input levels (100 %, 80 %, 50 %, and 0 %) with and without straw additions. We assessed soil nutrients, functional gene abundance, potential pathogen risks (Fusarium oxysporum f. sp. Lycopersici, Fol) and beneficial taxa (Pseudomonas, Pse), soil quality index (SQI), multifunctionality, yield, and economic performance. We hypothesized that moderate P reduction, particularly when integrated with straw return, can maintain S. lycopersicum productivity while enhancing soil health through improved microbial functional potential and disease suppression. Specifically, we asked: (1) How does reduced P fertilization affect yield, economic return, nutrient status, and microbial functional indicators in an intensive S. lycopersicum system? (2) Can straw addition under reduced P input amplify soil multifunctionality and optimize the balance productivity with pathogen suppression
Assessing the reliability of camera-based identification, activity monitoring, and location in housing systems on dairy farms
No full textInternational audienceVideo-based livestock monitoring offers a noninvasive, cost-effective, and scalable alternative to direct human monitoring, but also to commonly used collar or ear tag devices on farms. It enables simultaneous real-time observation of multiple animals while avoiding stress and injuries from physical devices. However, single-camera systems face challenges such as blind spots and limited individual tracking, especially in barns lacking corridor layouts. These limitations can be overcome using multi-camera, multi-cow tracking (MCMCT) systems that integrate deep learning and statistical techniques to enable continuous detection, identification, activity classification, and zone location of animals in the barn, under commercial conditions. This environment is characterized by high stocking density (in m 2 per cow), occlusions, and variable lighting. In this study, a commercial MCMCT system was tested over 31 d (May 2025) on 3 Holstein dairy farms in western France. Herd size ranged from 70 to 250 lactating cows and used automatic milking systems (AMS), which allowed identification of all animals when milked. Individual detection performance of this MCMCT system was then validated compared with official AMS records. A dedicated hybrid confusion matrix framework was developed to jointly assess detection and identification errors in the sequential process, allowing precise calculation of recall, precision, and F1-scores at both stages. Overall, this MCMCT system achieved over 90% detection recall and 87% to 93% precision, successfully detecting continuously more than 9 out of 10 cows daily. Identification was more challenging, with recall varying from 69% to 78% and precision above 83%, resulting in F1-scores of 79% to 82%. The performance of detection varied significantly between day and night in 2 out of 3 farms (H1 and H2), with recall rates dropping to 76% at night and exceeding 94% during peak daylight, underscoring the impact of lighting and activity patterns. Activity classification and zone location were robust, with F1-scores exceeding 87%, demonstrating the system's capacity to provide practical insights for herd management such as monitoring individual behaviors, identifying high-density zones around resources, and supporting daily management decisions. This work confirms the system's practical viability as a scalable, noninvasive monitoring solution effective under commercial farm complexities such as crowding, occlusion, and lighting variability. The integration of day-night performance analysis and the hybrid confusion matrix provide a rigorous and transparent framework for assessing system reliability, critical for deploying precision livestock farming technologies. Identification performance decreased under overcrowded conditions. Overcrowding is defined here as a surface area of less than 9 m 2 per cow or less than than one cubicle per cow, as recommended by the EFSA Panel on Animal Health and Animal Welfare in 2023. The system demonstrates significant potential to support and enhance herd management, early disease detection, and animal welfare monitorin
Clustering of the dynamics of milk lactose content throughout lactation and identification of variation factors
No full textInternational audienceInterest in milk lactose content (LC) has grown due to its potential as an indicator of udder health and metabolic disorders in dairy cattle. However, the variability of LC dynamics during lactation remains poorly described, and a better characterization of these dynamics could clarify our understanding of LC variations among cows, and potentially those due to udder health and metabolismrelated variations. The aim of this study was to identify distinct patterns of LC dynamics and assess their environmental and genetic determinants, as well as their phenotypic and genetic associations with milk yield, Na, K, SCC, and their phenotypic associations with fat-toprotein ratio (FPR) and BHB. A total of 1,980,693 testday records were analyzed from 183,150 Holstein cows in 2,239 herds across France. At least 2 records in the first 90 d and 4 records between 7 and 300 DIM were available for each cow, averaging 7.3 records per cow. Functional principal component analysis was used to describe LC dynamics throughout lactation. This approach involved smoothing the LC curves for each cow and then summarizing their overall shape using 3 principal components: average LC throughout lactation, LC slope and LC at mid lactation. Dynamics of LC were grouped into 6 clusters. Three clusters (3, 4, and 5) represented 86% of the data and shared similar dynamics with a flat trend after an initial rise in LC at early lactation and different average LC levels (cluster 3: 4.68%, cluster 4: 5.10%, cluster 5: 4.86%). Environmental and intrinsic animal factors explained 69% of the variability in average LC among clusters 3, 4, and 5, with cow parity and LC EBV identified as the main intrinsic contributors. The remaining clusters (1, 2, and 6) showed LC levels similar to the mean of the dataset (LC: 4.88% ± 0.19%) until 150 DIM. Thereafter, 2 clusters displayed negative LC slopes (cluster 1: -0.13% and cluster 6: -0.07% per month of lactation) and one a positive slope (cluster 2: +0.05% per month). Fifteen percent of the variations in the LC slopes of clusters 1, 2, and 6 was explained by environmental factors, mainly calving season: winter calving was associated with clusters 1 and 6, and summer calving with cluster 2. The remaining unexplained negative slope variation from mid lactation onward appears to be related to distinct patterns characterized by higher FPR and milk BHB concentrations preceding the decline in LC, followed by increased SCC after 150 DIM. The lactosebased clusters also corresponded to distinct curves for milk sodium contents, and there were slight correlations for potassium levels, indicating different equilibria between the 3 main osmotic agents (lactose, sodium, and potassium), probably to maintain milk osmolarity. As a result, LC clustering uncovered meaningful physiological profiles: average LC levels were primarily driven by parity and genetics, whereas LC slope variations appeared to be more sensitive to environmental and health-related factors. These findings support the potential of LC dynamics, accessible via mid-infrared spectra, to serve as functional biomarkers for udder health and, potentially, of metabolic status
Pentadecanoic acid in the French diet: Absolute quantitative assessment and contributions of dairy and non-dairy foods using a market basket approach
No full textInternational audiencePentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) are odd-chain fatty acids, mainly described in dairy products, as they constitute 1% and 0.5% of total ruminant milk fatty acids. They are thus often considered as plasma biomarkers of dairy intake. Yet, their detection in some non-dairy foods has challenged this exclusivity. To identify the dietary sources of OCFAs, a broad food panel was analyzed by GC-MS, including dairy (cheese, yogurt, butter…), meat (beef, pork, chicken…), different fish species and fish oils, vegetal oils, fruits and vegetables etc. Results confirmed that C15:0 and C17:0 represented on average 1.5% and 0.8% of total fatty acids in dairy products. C15:0 was almost exclusively abundant in dairy, whereas C17:0 also appeared in notable amounts in beef and, to a lesser extent, pork. Low amounts of C15:0 and C17:0 were detected in fish, whereas higher amounts of C17:0 were found in fish oils. Thus, dairy products remain the richest source of C15:0, containing the highest amounts per portion
Les fausses publications scientifiques menacent de submerger la recherche contre le cancer
No full textInternational audienceUne étude récente pointe un chiffre alarmant : plus de 250 000 articles scientifiques liés au cancer pourraient avoir été fabriqués de toutes pièces entre 1999 et 2024. Cette production s’accélère et menace la production scientifique honnête