Génotypage et cryoconservation d'embryons équins : état des courses. Premières gestations après transfert d'embryons équins biopsés et sexés

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Premières gestations après transfert d'embryons équins biopsés et sexés

Embryo transfer coupled with embryonic genotyping from biopsied cells is a powerful tool for genetic selection. We have tested two technics of embryonic biopsy on in vitro and in vivo viability of equine embryo: by section (study 1) and by aspiration (study 2). We have also sexed the embryos. More than 70 embryos were collected 6.75 or 7 days post ovulation. Study 1: after biopsy and 24h of in vitro culture, morphological notation of biopsied embryos was significantly worse than control (P=0.001). After transfer, less than 20% of gestation at Day 14 was obtained with biopsied embryos versus almost 70% for control. Study 2: after biopsy and 24h of in vitro culture, morphological notations of biopsied embryos and controls were not significantly different (P=0.89). After transfer, half of the recipients with biopsied embryos were pregnant at Day 30 and a third with control. Biopsy by aspiration must be chosen for genotyping in equine species. Sex diagnosis was efficient for all biopsies (study 1) and for more than 80% in study 2. For both studies, all sex diagnoses were correct.Le transfert d'embryons couplé au génotypage de l'embryon à partir de biopsies embryonnaires est un puissant outil de diffusion du progrès génétique. Dans ce travail, nous avons testé l'impact de deux techniques de biopsie embryonnaire sur la survie in vitro et in vivo d'embryons équins : par coupe (étude 1), par aspiration (étude 2), et génotypé les embryons (sexe). Plus de 70 embryons ont été collectés sur des ponettes Welsh 6,75 ou 7 jours post ovulation. Etude 1 : après biopsie et 24h de culture in vitro, la note morphologique des embryons était négativement affectée par la biopsie, comparée à celle des embryons témoins (P=0,001). Après transfert, moins de 20% de DG14 ont été obtenus contre presque 70% avec les témoins. Etude 2 : après biopsie et 24h de culture in vitro, la note morphologique des embryons biopsiés était identique à celle des témoins (P= 0,89). A DG30, la moitié des receveuses d'embryons biopsiés était gestante, contre un tiers pour les receveuses d'embryons témoins. La biopsie par aspiration est donc à privilégier pour cette espèce. Le sexe des embryons a pu être prédit sur toutes les biopsies (étude 1) et sur plus de 80% (étude 2). Toutes les prédictions se sont révélées exactes

Preimplantation genetic diagnosis in Welsh pony embryos after biopsy and cryopreservation

Preimplantation genetic diagnosis and embryo cryopreservation are important tools to improve genetic management in equine species with marked consequences on the economic value, health, biodiversity, and preservation of the animals. This study aimed to develop a biopsy method at the blastocyst stage that provides viable genotyped cryopreserved Welsh pony embryos. Embryos were collected at d 6.75 to 7 after ovulation. Biopsies were performed with either a microblade or a micropipette. After biopsy, embryos were cryopreserved. The survival rate of biopsied embryos was evaluated on fresh and cryopreserved embryos either 24 h after in vitro culture or after transfer to recipients. Fresh and nonbiopsied embryos were used as controls. Sex, coat color genes, myotony (neuromuscular disorder) diagnosis, and markers of parentage were investigated using PCR on biopsied cells after whole-genome amplification and on remaining embryos. The embryo survival rate after transfer was not affected by the micropipette biopsy (50%, n = 8; 43%, n = 7; and 50%, n = 12, at d 30 for fresh biopsied embryos, vitrified biopsied embryos, and control embryos, respectively) but was significantly reduced by the use of microblade biopsy: 9 (n = 11) vs. 67% (n = 12) for control embryos. Successful sex determination was achieved for 82% (n = 28) of the micropipette biopsies and 100% (n = 50) of the microblade biopsies. Sex determined on biopsied cells was found to correspond completely (100%) with that determined on the remaining embryo (n = 37). More than 90% of the parentage checking markers, coat color, and myotony diagnosis were successfully determined on biopsies obtained with either a micropipette or a microblade. Mendelian incompatibility (7.5 and 5.5%) and embryo genotyping errors (6.6 and 8.6%) were low and not significantly different between the 2 methods. In conclusion, for the first time, pregnancy at Day 30 was obtained after transfer of Welsh pony biopsied and vitrified embryos >300 μm in diameter to recipient pony mares. The biopsied cells collected enabled multigenetic embryo diagnoses to be performed to a high degree of accuracy. The micropipette biopsy is the better method to apply on Welsh pony embryos

: Zone Atelier Plaine & Val de Sèvre

International audienceAgriculture is currently facing unprecedented challenges: ensuring food, fiber and energy production in the face of global change, maintaining the economic performance of farmers and preserving natural resources such as biodiversity and associated key ecosystem services for sustainable agriculture. Addressing these challenges requires innovative landscape scale farming systems that account for changing economic and environmental targets. These novel agricultural systems need to be recognized, accepted and promoted by all stakeholders, including local residents, and supported by public policies. Agroecosystems should be considered as socio-ecological systems and alternative farming systems should be based on ecological principles while taking societal needs into account. This requires an in-depth knowledge of the multiple interactions between sociological and ecological dynamics. Long Term Socio-Ecological Research platforms (LTSER) are ideal for acquiring this knowledge as they (i) are not constrained by traditional disciplinary boundaries, (ii) operate at a large spatial scale involving all stakeholders, and (iii) use systemic approaches to investigate biodiversity and ecosystem services. This study presents the socio-ecological research strategy from the LTSER "Zone Atelier Plaine & Val de Sèvre" (ZA PVS), a large study area where data has been sampled since 1994. Its global aim is to identify effective solutions for agricultural development and the conservation of biodiversity in farmlands. Three main objectives are targeted by the ZAPVS. The first objective is intensive monitoring of landscape features, the main taxa present and agricultural practices. The second objective is the experimental investigation, in real fields with local farmers, of important ecosystem functions and services, in relation to pesticide use, crop production and farming socio-economic value. The third aim is to involve stakeholders through participatory research, citizen science and the dissemination of scientific results. This paper underlines the relevance of LTSERs for addressing agricultural challenges, while acknowledging that there are some yet unsolved key challenges

Untargeted metabolomic analyses reveal the diversity and plasticity of the specialized metabolome in seeds of different Camelina sativa genotypes

International audienceDespite the essential role of specialized metabolites (SMs) in the interaction of plants with the environment,studying the ability of crop seeds to produce these protective compounds has been neglected. Furthermore,seeds produce a myriad of SMs, providing an interesting model to investigate their diversity and plasticity.Camelina sativagained a lot of interest in the past few years as a rustic oilseed crop. A characterization ofseed SM landscapes in six camelina genotypes grown in the field and harvested during five growing seasonshas been undertaken in this work. This allowed a comprehensive annotation of seed SMs combining analysesthat cluster SMs based on their chemical structures and co-accumulation patterns. These data showed broadeffects of the environment on the stimulation of the seed SM. Among well-annotated compounds, flavonolswere identified as the metabolic class characterized by high plasticity, revealing significant variable accumula-tion according to the year and/or the genotype. Lastly, a deeper characterization of primary metabolites andlipids in two selected genotypes has been performed. We showed that, in addition to flavonols, alkaloids andglucosinolates displayed a higher phenotypic plasticity with respect to most of the primary metabolites, inclu-ding some sugars and major storage compounds such as fatty acids, proteins and most lipid classes (e.g. dia-cylglycerols, triacylglycerols), but similar plasticity compared with free amino acids and carboxylic acids. Thiswork highlighted major and unexplored effects of the environment on the seed SM, demonstrating that seedsexhibit a dynamic and plastic metabolism, with an impact on seed quality

Bourdieu

Les débats passionnels à propos de l'œuvre de Pierre Bourdieu et de ses engagements publics ont longtemps limité l'expression d'une critique scrupuleuse de son travail. Alors que ces débats commencent à s'estomper, ce livre propose une analyse du cœur de son projet intellectuel : sa théorie de la pratique. Les textes qu'il réunit examinent l'usage des notions que Bourdieu a introduites dans le lexique de la sociologie et de l'anthropologie et qui en font désormais partie : champ, habitus, capital, réflexivité, familiarité, intérêt, désintéressement, critique, position scolastique. Sociologues, philosophes et linguistes s'attachent ainsi, chacun à leur manière, à rendre compte d'un aspect de la théorie de la pratique de Bourdieu, en ouvrant une réflexion sur sa pertinence et sur les lacunes et contradictions qui ont provoqué sa remise en cause ou son rejet. Ce livre n'est pas un plaidoyer pour ou contre Bourdieu. Il cherche plutôt à présenter une confrontation raisonnée de ses thèses avec celles qui ont été élaborées par les approches qui, depuis une vingtaine d'années maintenant, ont renouvelé l'enquête en sciences sociales, en l'orientant résolument vers l'analyse empirique de la pratique, dont la collection « Raisons pratiques » a été l'un des lieux majeurs de développement en France

Sex and PRNP genotype determination in preimplantation caprine embryos

Chantier qualité GAThe objective of this study was to test the accuracy of genotype diagnosis after whole amplification of DNA extracted from biopsies obtained by trimming goat embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer. Whole genome amplification (WGA) was performed using Multiple Displacement Amplification (MDA). Sex and prion protein (PRNP) genotypes were determined. Sex diagnosis was carried out by PCR amplification of ZFX/ZFY and Y chromosome-specific sequences. Prion protein genotype determination was performed on codons 142, 154, 211, 222 and 240. Embryos were collected at day 7 after oestrus and biopsied either immediately after collection (blastocysts and expanded blastocysts) or after 24 h of in vitro culture (compacted morulae). Biopsied embryos were frozen by vitrification. Vitrified whole embryos were kept as control. DNA of biopsies was extracted and amplified using MDA. Sex diagnosis was efficient for 97.4% of biopsies and PRNP genotyping was determined in 78.7% of biopsies. After embryo transfer, no significant difference was observed in kidding rate between biopsied and vitrified control embryos, whereas embryo survival rate was different between biopsied and whole vitrified embryos (p = 0.032). At birth, 100% of diagnosed sex and 98.2% of predetermined codons were correct. Offspring PRNP profiles were in agreement with parental genotype. Whole genome amplification with MDA kit coupled with sex diagnosis and PRNP genotype predetermination are very accurate techniques to genotype goat embryos before transfer. These novel results allow us to plan selection of scrapie-resistant genotypes and kid sex before transfer of cryopreserved embryo

NBAS mutations cause a multisystem disorder involving bone, connective tissue, liver, immune system, and retina.

We report two unrelated patients with a multisystem disease involving liver, eye, immune system, connective tissue, and bone, caused by biallelic mutations in the neuroblastoma amplified sequence (NBAS) gene. Both presented as infants with recurrent episodes triggered by fever with vomiting, dehydration, and elevated transaminases. They had frequent infections, hypogammaglobulinemia, reduced natural killer cells, and the Pelger-Huët anomaly of their granulocytes. Their facial features were similar with a pointed chin and proptosis; loose skin and reduced subcutaneous fat gave them a progeroid appearance. Skeletal features included short stature, slender bones, epiphyseal dysplasia with multiple phalangeal pseudo-epiphyses, and small C1-C2 vertebrae causing cervical instability and myelopathy. Retinal dystrophy and optic atrophy were present in one patient. NBAS is a component of the synthaxin-18 complex and is involved in nonsense-mediated mRNA decay control. Putative loss-of-function mutations in NBAS are already known to cause disease in humans. A specific founder mutation has been associated with short stature, optic nerve atrophy and Pelger-Huët anomaly of granulocytes (SOPH) in the Siberian Yakut population. A more recent report associates NBAS mutations with recurrent acute liver failure in infancy in a group of patients of European descent. Our observations indicate that the phenotypic spectrum of NBAS deficiency is wider than previously known and includes skeletal, hepatic, metabolic, and immunologic aspects. Early recognition of the skeletal phenotype is important for preventive management of cervical instability