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Chapter 11 - Modeling spatiotemporal distribution of fish species richness and abundance
No full textInternational audienceThis chapter proposes a general overview of data and methods allowing for spatiotemporal representation of marine fish species distribution and abundance. The most widespread approach to model and map the spatiotemporal distribution of fish species is described. The value of these approaches’ outputs to improve knowledge about the dynamics of marine ichthyofauna, estimate the consequences of human disturbances, and simulate prospective scenarios accounting for global change and management measures is presented. Last, the interest in this quantitative information to prioritize protection areas and improve fisheries management systems is evidenced
Alternative approaches to antibiotics in the control of mastitis in dairy cows: a review
No full textInternational audienceBovine mastitis is the most widespread and economically burdensome condition affecting dairy herds worldwide, causing substantial financial losses in the livestock and dairy sectors. The main approach to treating mastitis in dairy cows is based on the administration of antibiotics. However, their widespread use has led to the emergence of antibiotic-resistant pathogens, and thus to numerous food safety problems. Consequently, a growing body of scientific research has been directed towards exploring new and effective therapeutic alternatives for the management of bovine mastitis, which could replace conventional antibiotic therapy. This review surveys the various alternative strategies employed in the prevention and treatment of mastitis in dairy cattle. These strategies include nanoparticle therapy, bacteriophage therapy, vaccination, phytotherapy, the use of animal proteins, probiotics and bacteriocins. In addition, the potential synergistic effects resulting from the combination of these treatments has shown real benefits that will be highlighted
Rôle de la formation initiale dans l’attractivité des métiers de la filière porcine
No full textInternational audienceStrengthening the attractiveness of jobs in the pig sector among younger generations is a major challenge to address given the difficulties in recruiting employees and with generational renewal. This study aimed 1) to inventory curricula in high schools (French vocational Baccalaureate – Bac Pro) and advanced technician’s certificate (BTS) programmes that included pig-farming courses and 2) to identify educational practices and strategies that teachers used to improve the image of the pig sector among their students, as well as the obstacles they encountered. Among the 69 BTS curriculum in animal sciences and production listed on the ONISEP and Parcours Sup websites, 82% mentioned pigs, compared to only 18% of the 246 Bac Pro curricula in Farm Management. These programmes were located mainly in the Grand Ouest and Auvergne Rhône-Alpes regions of France. Interviews with 10 teachers confirmed that students had little interest in working in the pig sector. Students’ negative perceptions of pig farming were related to the indoor working conditions, strong odours, and animal-welfare concerns. Teachers cited farm visits, practical classes about farms, and meetings with enthusiastic professionals as mechanisms to raise awareness about the sector. Difficulty finding farms that accept visitors, particularly in regions with low farming density or due to biosecurity procedures, was a large obstacle. Modernisationof high-school farms or partnerships with local farmers were strong mechanisms. More broadly, teachers highlighted the need for more positive communication by the media about the pig sector to make it attractive to students as future job candidates
Evolution of microclimate following small patch de-sealing and revegetation in urban context
No full textInternational audienceThis research explores the impact of de-sealing a 64 m 2 patch (Oasis) after introducing indigenous vegetation, four trees and herbaceous species, on local microclimate conditions in an urban context. Over two years, microclimate variables were monitored and thermal comfort was evaluated with the Universal Thermal Climate Index (UTCI). The Oasis experienced a noticeable reduction in Ts compared to surrounding asphalted areas, with a daily mean difference in maximum surface temperatures of 18.4 • C the first summer and 23.0 • C the second, attributed to the development of the herbaceous layer, which covered 60 % of the Oasis three months after sowing and above 90 % from the second year. This Ts is partly responsible for improving thermal comfort during the day. Tree shading induced further local cooling, with a decrease of up to 8 • C of UTCI in shaded areas. No evidence of lower nocturnal Ta compared to sealed reference was shown, possibly due to the small size of the patch and air mixing with the surroundings. However, as the low vegetation grew, the nocturnal de-sealed patch Ta got closer to mature meadow values. Modeling using UMEP and SOLWEIG projected further improvements in thermal comfort in the coming years during the daytime considering future tree dimensions. During nighttime, the trees would induce a significant radiative trapping. This study demonstrates that small-scale de-sealing and revegetation projects can provide meaningful microclimate improvements in urban environment as early as the first year. In the following years, the development of vegetation further helps cities to adapt to climate change
Espaces critiques.Dimension spatiale des rapports sociaux et champ scientifique.
No full textInternational audienceDepuis le milieu des années 2000, la question de la dimension spatiale des rapports sociaux, des inégalités et des formes de domination est de plus en plus explorée en géographie française, mais aussi dans d’autres sciences sociales comme la sociologie et la science politique. L’ouvrage poursuit cette dynamique en contribuant à une forme de réflexivité, soit en explicitant des positionnements théoriques soumis à la discussion collective, soit en analysant la recherche comme des pratiques sociales qui s’affrontent à des cloisonnements ou des hiérarchies entre disciplines, langues ou champs nationaux, qu’il s’agit d’identifier pour pouvoir les dépasser. Espaces critiques peut alors se comprendre de deux façons : ce sont d’abord les différentes conceptions de la dimension spatiale mais aussi scalaire des rapports sociaux qu’élaborent les recherches critiques ; ce sont aussi les espaces sociaux, qui ne sont pas seulement académiques, dans lesquels les recherches sont élaborées, discutées et transmises
Celebrating the 25th Anniversary of the International Society for Seed Science
No full textInternational audienceIt has been 25 years since the International Society for Seed Science (ISSS) was founded, marking a quarter of a century of shared dedication to advancing seed science worldwide. Over these years, the ISSS has served the scientific community of seed scientists, bringing them together into a vibrant and dynamic community driven by the collaborative spirit of its members. With great pride and a sense of history, I write this foreword to celebrate the society's enduring impact and the remarkable journey we have undertaken together.The founding of the ISSS is a story of visionaries who recognized the need for a global platform to foster collaboration and innovation in seed science. Mike Black, among others, played a pivotal role in establishing the society, and their legacy continues to inspire our work today.Central to the ISSS's success has been the dedicated leadership of its presidents, secretaries and treasurers (Table 1). Over the generations, these individuals have shouldered the responsibility of guiding society's growth and direction. They have been supported by the invaluable counsel and contributions of additional trustees serving on the Executive Committee. This collective leadership has shaped the ISSS into the thriving and dynamic organization it is today.The main focal point of the ISSS is the organization of meetings and conferences. These gatherings have been instrumental in fostering connections, sparking ideas, and shaping careers. For many of us, ISSS conferences have been defining in career moments. They provide a rare opportunity to step away from the daily demands of research and administrative duties and take time to reflect on our research and its place in the broader context of seed science. In an increasingly fast-paced and interconnected world, these interludes are more important than ever. Reflecting on my journey, I vividly recall the excitement of attending my first ISSS conference, meeting future mentors and collaborators, and experiencing the dynamic exchange of ideas that these events facilitate. Science thrives on discovery and collaboration, and ISSS meetings provide the perfect environment to nurture both.The ISSS values its efforts to support and encourage young scientists. The 14th ISSS Biennial Conference at Sorbonne University in Paris stands out as an excellent example. Through financial support, the society enabled 62 PhD students to attend, offering discounted registration fees and 15 travel grants. These efforts ensure the future of seed science remains bright, with new generations inspired to take up the mantle.As a global scientific society, the ISSS recognizes its responsibility to contribute to sustainability. We need to be committed to exploring alternative ways for members to connect, including virtual and hybrid meeting formats, to complement in-person gatherings. We will continue to rotate the location of our biennial meetings across different continents, ensuring accessibility for members worldwide and reducing the need for long-distance travel for some. By adopting these practices, we aim to balance the benefits of collaboration and community building with the need to protect our planet for future generations.Training young scientists remains a cornerstone of our mission, but it is increasingly important to extend our reach beyond traditional academic boundaries. Social media and digital platforms provide opportunities to inspire younger generations about the importance of seeds in agriculture, ecosystems and daily life. Amid growing misinformation, the ISSS plays a crucial role in promoting transparency and collaboration. The transition of our journal</p
Breakthrough innovations in industrial cheesemaking processes
No full textInternational audienceCheese, which has played a crucial role in mankind history, is now produced using optimized and automated processes. However, these productions still have significant potential for improvement in terms of the technological, economic, and environmental performance and of the product quality. Controlling milk composition and curd cutting time pave the route for optimizing cheesemaking performances and cheese characteristics, while ripening time can be reduced by uncoupling cheese texture and aroma construction or properly selecting cheese ripening strains and enzymes. Omics techniques now make it possible to screen starters both having technological and functional or probiotic properties, or preventing fungal or bacteria spoilage. Similarly, the mining of the whole processing data set using artificial intelligence, expert knowledge and multi-objective optimization has enormous potential for identifying thebest possible cheesemaking route. By taking environmental performance into account, the latter can identify solutions that reduce consumptions of water, energy and cleaning agents
Use of stable isotope-labeled fatty acids to measure desaturase activities with negative chemical ionization GC-MS
No full textInternational audienceA C T Fatty acid desaturases are key enzymes in lipid metabolism. They introduce double bonds between defined carbons of the fatty acyl chain and catalyze rate-limiting steps in the biosynthesis of polyunsaturated fatty acids. For decades, in vitro desaturase activities have been determined by using radiolabeled fatty acids as substrates, incubated with tissue or cell fractions containing membrane-bound desaturases. However, handling radioactivity is being increasingly complicated due to safety and regulatory concern. Radiolabeled fatty acids are also expensive and many of them are not commercially available. There is therefore a crucial need to develop new methods. Although methods using unlabeled fatty acids as substrates have recently been validated, they are well suited for large tissue samples and did not achieve the same sensitivity as the radioactive ones. Here, we show that negative chemical ionization GC-MS on stable isotope-labeled fatty acids, derivatized to pentafluorobenzyl esters, now offers this opportunity, because of its high sensitivity in the selected ion monitoring mode. By using this simple and affordable improved method, we measured the kinetic parameters of mouse liver Δ6-desaturase for its two main substrates (C18:2 n-6 and C18:3 n-3; 10-13 µM). Moreover, this method enabled to compare Δ5desaturase apparent Km values (19-22 µM) for its two main substrates (C20:3 n-6 and C20:4 n-3). Finally, we reevaluated the controversial effect of freezing on desaturase activities by using both frozen rat tissues and cryopreserved human hepatocytes. This safe, reliable and sensitive method may be applied to other enzymatic activities involving fatty acids (elongation, hydroxylation) in miniaturized samples
Occurrence des résidus de médicaments vétérinaires dans les eaux destinées à la consommation humaine : cas de bassins versants bretons (Etude EXPO-VETO)
No full textLa Directive Cadre sur l’Eau (2000) fait état de la dégradation du bon état chimique des eaux superficielles et des eaux souterraines. Parmi les polluants émergents mis en cause figurent les résidus de médicaments qui représentent une menace diffuse et potentiellement persistante dans les hydro-systèmes. A ce jour, peu d’études se sont intéressées spécifiquement aux résidus médicamenteux vétérinaires (RMV). En France, la Bretagne est une région d'élevage intensif. 75% des eaux destinées à la consommation humaine (EDCH) sont issues d’eau de surface particulièrement vulnérables. Dans ce contexte, les objectifs de cette thèse sont de (i) sélectionner les sites à risque et les RMV d’intérêt, (ii) développer une méthode d’analyse pour la liste de composés retenus, (iii) acquérir des premières données d’occurrence par les RMV dans les ressources et eaux du robinet correspondante et (iv) identifier les sources des RMV à l’aide de l’étude de la contamination fécale associée dans les eaux brutes. Au niveau des RMV d’intérêt, 40 substances ont été sélectionnés en accord avec les pratiques vétérinaires bretonnes, les données de pharmacocinétique, leur devenir dans l’environnement et la faisabilité analytique. Les sites sélectionnés sont au nombre de 25 captages situés en contexte d’élevage intensif en Bretagne. La stratégie d’échantillonnage avait pour objectif de refléter les variations des prescriptions vétérinaires, les périodes d’épandages et le régime hydrique (étiage ou crues). Cinq campagnes de prélèvements ont été réalisées de mars 2017 à juin 2018, en entrée et sortie d’usine de potabilisation (200 échantillons). Les méthodes d’analyse nécessaires pour mesurer ces RMV ont été développées spécifiquement pour l’étude. Les résultats des analyses ont quantifié des RMV dans les ressources en eau (23 eaux de surfaces et 2 eaux souterraines) dans 32% à 47% des échantillons selon les campagnes. La diversité de molécules quantifiées est plus importante en période d’étiage. Les concentrations mesurées varient de 5 ng/l (la limite de quantification) à 2 µg/l. Dans les eaux traitées correspondantes, des RMV sont également quantifiés de 4% jusqu’à 65% des échantillons selon les campagnes. La diversité des molécules quantifiées était plus importante en période d’épandages. Les concentrations mesurées varient de 5ng/l à 200 ng/l environ. Ces concentrations en RMV dans les EDCH en Bretagne sont les premières données de contamination les plus importantes en nombre (200 échantillons), sur une période de temps (environ 1 année) et à l’échelle d’une région en France
Younger dams without older litters in the cage increases mouse pre-weaning survival
No full textInternational audienceWhen attempting to reduce mouse breeding for research, a problem remaining largely unaddressed is the issue of mouse pre-weaning mortality. Studies have been reporting mortality levels from less than 10% to 49%, often reaching above 20%. Considering an average of 4.5 million mice used in EU research yearly, and assuming a conservative mortality level of 20%, up to 1.1 million mice may have been dying annually, before being available for use in science. Furthermore, the more pups that are bred, the more breeding resources are needed, making this a world-wide animal welfare, economic, logistic, and sustainability issue. Pre-weaning mortality, reproductive, and welfare parameters have previously been linked with social and environmental factors, such as cage enrichment (e.g. nest material and amount), bedding material, dam handling and parity, cage temperature and light intensity, and more recently, litter overlap, which happens when new pups are born in the presence of older pups already in the cage. Still, how these social factors interact with the cage microenvironment to impact pup survivability remains unknown. Therefore, this study aimed to evaluate pup survival as function of the most relevant environmental and social factors for mouse pups, and their degree of importance relative to pup survival. A total of 3380 pups from 509 C57BL/6J litters were counted twice daily from birth until day four post-partum for accurate detection of mortality. Pup probability to die was modelled as a function of dam age, number of pups born, number and age of older pups in cage. Additional measurements were performed for 172 litters (1181 pups), to continuously monitor cage temperature, light intensity, vibration, and frequency of human movements near mouse cages, for four days post-partum. Nests were scored daily regarding their height and closure of the walls surrounding the nest cavity. A Decision Tree was built to describe the environmental and social pathways leading to pup death. Probability of pups to die increased with the increase in dam age, number and age of older pups in the cage, and in small (≤6 pups) and large (>11 pups) focal-litters. Higher temperatures (>23.6°C) and nest scores (>3.75) compensated some of the socially-risky situations for pup death. These findings can be implemented in strategies for reducing pre-weaning mortality, for a more welfare-friendly and sustainable mouse breeding for science