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L'insémination sous laparoscopie permet chez la brebie d'utiliser un milieu de congélation dénué de produits d'origine animale
No full textInternational audienceAnimal-derived products are widely used in sperm cryopreservation for their cryoprotective properties. These components, however, must be replaced because of sanitary risks. STEMALPHA.CRYO3 (Ref. 5617, Stem Alpha), called CRYO3, is a chemically defined preservation medium currently used for freezing human tissue and adult stem cells. The aim of this study was to evaluate the effects of a CRYO3-based medium and of two cooling rates on in vitro parameters and in vivo fertility of ram sperm. Six rams (Blanche du Massif Central) were subjected to sperm collection four times using an artificial vagina. Sperm were split and frozen in three media: an egg yolk and milk-based medium (positive control), a CRYO3-based medium (tested medium), and a medium without additives (negative control). The two cooling rates were related to the distance between the straws and the surface of liquid nitrogen during the freezing process (5 and 20 cm). Sperm membrane integrity (propidium iodide/SYBR-14), acrosome integrity (fluorescein isothiocyanate-peanut agglutinin/propidium iodide; FITC-PNA/PI), and mitochondrial membrane potential (JC-1) were assessed using flow cytometry, whereas functional membrane integrity was assessed using a hypo-osmotic swelling test and motion characteristics were evaluated using computer-assisted sperm analysis. Pregnancy rate, parturition rate, and prolificacy were evaluated after performing laparoscopic inseminations (n ¼ 75 ewes). Moreover, we characterised the freezing media thermodynamically using a differential scanning calorimeter. Statistical analyses were performed using R software. In vitro parameters were assessed using a mixed model including the time and the medium as fixed effects and the ram as a random effect. Pregnancy and parturition rates, following a binomial distribution, and prolificacy, assumed to follow a Poisson distribution, were analysed using generalised linear models, including the medium as a fixed effect and the ram as a random effect. Differences with P , 0.05 were considered statistically significant. The cooling rates had no significant effect except on the wobble motion parameter. The positive control medium showed significantly higher results than the CRYO3-based medium and the negative control medium for all in vitro parameters except for straightness motion parameter. Conversely, field trials showed no significant difference between the media for pregnancy rate (71, 64, and 74%), parturition rate (68, 61, and 74%) and prolificacy (2.0, 2.1, and 1.7), for the positive control, CRYO3-based medium, and the negative control, respectively. This study showed that the product, CRYO3, cannot replace egg yolk and milk in freezing extenders. Moreover, we showed that laparoscopic inseminations allowed a 74% parturition rate due to an easy and inexpensive medium comprising only a Tris buffer and glycerol. Although it could not be used on a large scale, this medium remains an option for international transport or long-term storage of genetic diversity
Controversial topics in agroecology: A European perspective
No full textInternational audienceSeven potential controversial topics in agroecology are presented and discussed from a European perspective comparing the position of Agroecology Europe (AEEU) obtained from an iterative, participatory approach with members and compared with published literature, including views from other parts of the world. The seven controversial topics are: i) use of agrochemicals; ii) small-scale and peasant fanning versus larger farms; iii) technological innovations in agriculture and precision fanning; iv) biotechnology and genetic engineering in agriculture; v) local and short food circuits; vi) social justice; vii) gender perspective. The analysis shows that there are diverse points of view related to geographical area and sociopolitical contexts. However, there are several convergences towards the ambition of redesigning fanning and food systems, as a lever acting on several topics, and in considering agroecology with a holistic, participatory, multiactor approach for a transition that is needed
Assessing agro-ecological practices using a combination of three sustainability assessment tools
No full textInternational audienceThe alignment of the environmental, economic and social sustainability of farms is necessary for enhancing the provision of public goods in farming. This study combines the use of three tools for the assessment of farm sustainability. It provides first insights into the sustainability performance of farms at different stages of agro-ecological transitions in 15 case studies covering a range of different farming systems across Europe. Each case study reflects a different-transition towards agro-ecological farming. The tools applied were COMPAS (an economic farm assessment tool); Cool Farm Tool (a greenhouse gas inventory, water footprint and biodiversity assessment tool); and the SMART Farm Tool (a multidimensional sustainability assessment tool).First results of the use of combined sustainability assessments deepen the understanding of different farming systems. Sustainability performance varies greatly between farms, but overall, agro-ecological farms tend to enhance biodiversity and water quality. For soil quality, no clear patterns could be identified. The same applies to economic performance at different stages of the agro-ecological transition. Quality of life was generally rated medium to high on all investigated farms. The combined sustainability assessment enabled the identification of areas for further policy development.Aligning the tools required harmonising definitions, simplification and assumptions with regard to the input data of the tools
SyAM - Systèmes alimentaires du milieu : Des outils pour développer la durabilité des systèmes alimentaires
No full textLes « systèmes alimentaires du milieu » (SyAM) sont des partenariats innovants, à mi-chemin entre circuits courts et circuits longs, dont la construction n'a rien d'évidente et nécessite d'être accompagnée. Ce livret, élaboré dans un processus de rencontre entre chercheurs et acteurs, met l'accent sur plusieurs questions clés : faire du système d'acteurs un véritable collectif, construire un partenariat, créer et partager la valeur, s'entendre sur un cahier des charges « complet », évaluer et suivre les performances, mettre en place un « modèle » pour l'accompagnement et la résilience. Chaque fiche met en exergue certains points qui nous sont apparus pertinents pour la construction de ces systèmes. Elles s'adressent aussi bien aux opérateurs économiques désireux de créer un SyAM (agriculteurs, transformateurs, distributeurs, sociétés de restauration collective, etc.), qu'aux collectivités territoriales ou organisations professionnelles soutenant leur développement. Ce livret ne donne pas à voir d'exemples approfondis de SyAM. Nous renvoyons pour cela à 12 études de cas également disponibles. Les fiches peuvent être lues de façon indépendantes mais aussi croisées afin de mieux comprendre la spécificité de ce qui fait « SyAM » et la complexité de ces démarches
Shift of belowground traits during perennial grain growth phase in annual grains crop rotation
No full textInternational audienc
Contributions of tenderness, juiciness and flavor liking to overall liking of beef in Europe
No full textInternational audienceThis study evaluated the contributions of sensory traits to overall liking in Europe. Perceptions by untrained consumers of tenderness, juiciness, flavor liking and overall liking were determined using the Meat Standards Australia protocols. According to European consumer testing with European beef samples, flavor liking was the most important contributor (39%) to beef overall liking, followed by tenderness (31%) and juiciness (24%) (P0.94). The improvement in tenderness over the last decades may explain the highest contribution of flavor liking nowadays. Flavor liking is therefore the main driver of variability in overall liking. Juiciness is the least robust trait which could be influenced by other traits during consumer perception. For outstanding steaks, each sensory trait should have excellent scores and high contributions to overall liking. For medium cuts, one sensory trait with a low score has the potential to be compensated by other traits with higher scores and more emphasis will be placed on the trait with the lowest perception
Various Statistical Approaches to Assess and Predict Carcass and Meat Quality Traits
No full textInternational audienceThe beef industry is organized around different stakeholders, each with their own expectations, sometimes antagonistic. This article first outlines these differing perspectives. Then, various optimization models that might integrate all these expectations are described. The final goal is to define practices that could increase value for animal production, carcasses and meat whilst simultaneously meeting the main expectations of the beef industry. Different models previously developed worldwide are proposed here. Two new computational methodologies that allow the simultaneous selection of the best regression models and the most interesting covariates to predict carcass and/or meat quality are developed. Then, a method of variable clustering is explained that is accurate in evaluating the interrelationships between different parameters of interest. Finally, some principles for the management of quality trade-offs are presented and the Meat Standards Australia model is discussed. The “Pareto front” is an interesting approach to deal jointly with the different sets of expectations and to propose a method that could optimize all expectations together
Deleterious impact of a generic temozolomide formulation compared with brand‐name product on the kinetic of platelet concentration and survival in newly diagnosed glioblastoma
No full textInternational audienceAbstract Chemo‐induced thrombocytopenia is a limiting toxicity among patients receiving temozolomide (TMZ) as first‐line treatment for glioblastoma. We aimed to compare early platelet concentration kinetics, hematological safety profile, and impact on survival following the initiation of either the brand‐name or a generic TMZ formulation. A retrospective trial was conducted in patients suffering from newly diagnosed glioblastoma. Patients were treated with TMZ at 75 mg/m 2 per day during six weeks, concomitantly with radiotherapy. Platelet concentration was collected each week. Primary endpoint was to perform a linear mixed‐effect model of platelet concentration kinetic over weeks. A total of 147 patients were included as follows: 96 received the brand‐name TMZ, and 51 received a generic TMZ formulation. Exposition to the generic was a significant variable that negatively influenced the platelet kinetics in the radiotherapy and concomitant TMZ phase, P = 0.02. Grade ≥3 chemo‐induced thrombocytopenia was more frequent in the generic group: 19.6% [95% CI 8.7‐30.5%] vs 3.1% [0‐6.6%], P = 0.001. Exposition to the generic formulation of TMZ led to increase early treatment discontinuation due to TMZ‐induced thrombocytopenia and was a worsening independent prognostic factor on overall survival: adjusted HR 1.83 [1.21‐2.8], P = 0.031. These data suggest that exposition to a generic formulation of TMZ vs the brand‐name product is associated with higher early platelet decrease leading to clinically relevant impacts on treatment schedule in glioblastoma. Further prospective trials are needed to confirm these results
Perennial crops for sustainable soil management – Symbiotic fungi benefit from cultivation of a model crop for perennial cereal grain production in Europe.
No full textInternational audienc
Agroecological practices supporting food production and reducing food insecurity in developing countries: A study on scientific literature in 17 countries
No full textThis report represents the initial effort to structure existing knowledge about agroecology as farming and food system in support of the EC Knowledge Centre on Food and Nutrition Security (https://ec.europa.eu/knowledge4policy/global-food-nutrition-security_en). Scientific literature has been screened on a selection of developing countries in which food and nutrition security and sustainable agriculture represent a focal sector for EU intervention (Benin, Burkina Faso, Cuba, Ethiopia, Ghana, Guatemala, Kenya, Lao PDR, Madagascar, Malawi, Mali, Nicaragua, Niger, Senegal, Tanzania, Togo, Zimbabwe). In total, 172 documents have been synthesised, a country brief has been prepared for each investigated country, and some general conclusions have been drawn. Overall, the majority of analysed publications focuses on small scale, extensive farming systems that produce food at subsistence levels and for sale on local markets. This includes smallholder farming producing staple crops (millet, sorghum, yam, etc.) or vegetable gardening for local markets. The agroecological practices that are mostly studied are: agroforestry, intercropping (or mixed cropping), introduction of legumes in rotations, soil and water conservation practices (mulching, return of crop residues, zaï holes etc.), use of animal manure, biocontrol methods to mitigate chemical pesticide use. At least 50% of the analysed papers report a positive contribution of agroecological practices to food security, mostly due to improved yields and/or a better economic situation of producers. The improvement of soil quality is key to improve yields and consequently income and food security; this can be achieved using various practices including the use of residue mulch from tree leaves in agroforestry, as well as crop mixtures or intercropping and longer more diversified crop rotations. Moreover, higher on-farm crop species diversity often results in more diversified diets. Diversified crop systems, including the introduction of agroforestry, improve household nutritional status and have positive links to better health conditions. On the other hand, the lack of access to inputs is an important limitation to the improvement of soil fertility (manure, mineral fertilizer, leaf litter, etc.), which remains a major hindrance for food security. The agroecological cultivation of cash crops, post-harvest practices and crop-livestock integration were overall lacking in the scientific analyses, as well as the assessments of fully agroecological systems compared to individual agroecological practices or groups of practices. The report identifies three factors required for the substantial development of agroecology at the farm level: more financial support from the government, greater scientific knowledge on novel agroecological practices, and a higher market value for agroecological products