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SOLVL - Les sols des aires de circulation dans les bâtiments des vaches laitières : évaluation sanitaire, environnementale et économique.
No full textAvec l’augmentation de la taille des troupeaux, les vaches passent plus de temps en bâtiment et les
bâtiments avec logettes se développent. Ainsi, les éleveurs se préoccupent davantage de la nature, de
la conception et des coûts des sols des aires de circulation et des conséquences de ceux-ci sur la santé
et le comportement des vaches. Le projet SOLVL a été conduit pour apporter de nouveaux éléments
sur ce sujet en combinant dans un premier temps une enquête postale à visée descriptive auprès de
645 élevages, puis dans un deuxième temps une enquête épidémiologique transversale sur la santé et
la propreté des animaux auprès de 87 élevages équipés des sols les plus courants (bétons pleins,
caillebotis et tapis) identifiés dans la première étape, pour finir par un suivi longitudinal dans 9 élevages
équipés de sols innovants. En pratique, ce projet a permis de compléter les interventions en élevage en
mettant au point une méthode de diagnostic des sols des aires de circulation, et de donner des
recommandations sur le choix, la conception, la réfection et l’entretien des sols.With the increase of dairy herd size, an extended time of the cows in housing and the development of
free-stall barns, the flooring in the walking areas of cubicle housing systems became a concern for
many farmers and stakeholders. Therefore, farmers must consider design, cost and also consequences
of flooring on health and behavior of dairy cows. This project was carried out to provide new elements
on flooring in the walking area. First, a descriptive survey was conducted among 645 farms. Then, an
epidemiological survey was conducted over winter 2015, where 87 farms were randomly selected from
the 645 free-stall barns database in order to represent the seven most common types of flooring.
Eventually, nine innovative floors were assessed. This study led to complement observations in farms
by the creation of methods to make a diagnosis of flooring. Also, many recommendations and advices
were made to better improve conception and renovation and to help farmers to choose the best type of
floor for their dairy cows
Comment les filières agricoles influencent-elles l’adoption de pratiques écologiques à l’échelle des exploitations?: Etude sur le secteur porcin
No full textNotre étude examine, pour le secteur porcin du Grand Ouest de la France:
- comment la création de standards privés influence l’adoption de pratiques écologiques à l’échelle des exploitation;
- les rôles joués par les organisations de producteurs (OP) dans l’adoption de pratiques écologiques au niveau de la production agricole
Serum levels of miR-126 and miR-223 and outcomes in chronic kidney disease patients
No full textSeveral microRNAs (miRNAs) have been linked to chronic kidney disease (CKD) mortality, cardiovascular (CV) complications and kidney disease progression. However, their association with clinical outcomes remains poorly evaluated. We used real-time qPCR to measure serum levels of miR-126 and miR-223 in a large cohort of 601 CKD patients (CKD stage G1 to G5 patients or on renal replacement therapy – CKD G5D) from Ghent University Hospital and 31 healthy controls. All-cause mortality and cardiovascular and renal events were registered as endpoints over a 6 year follow-up period. miR-126 levels were significantly lower from CKD stage G2 on, compared to controls. The serum levels of miR-223 were significantly lower from CKD stage G3B on. When considering overall mortality, patients with levels of either miR-126 or miR-223 below the median had a lower survival rate. Similar results were observed for CV and renal events. The observed link between the two miRNAs’ seric levels and mortality, cardiovascular events or renal events in CKD appears to depend on eGFR. However, this does not preclude their potential role in the pathophysiology of CKD. In conclusion, CKD is associated with a decrease in circulating miR-223 and miR-126 level
Nondestructive and Fast Vibration Phenotyping of Plants
No full textThe frequencies of free oscillations of plants, or plant parts, depend on their geometries, stiffnesses, and masses. Besides direct biomechanical interest, free frequencies also provide insights into plant properties that can usually only be measured destructively or with low-throughput techniques (e.g., change in mass, tissue density, or stiffness over development or with stresses). We propose here a new high-throughput method based on the noncontact measurements of the free frequencies of the standing plant. The plant is excited by short air pulses (typically 100 ms). The resulting motion is recorded by a high speed video camera (100 fps) and processed using fast space and time correlation algorithms. In less than a minute the mechanical behavior of the plant is tested over several directions. The performance and versatility of this method has been tested in three contrasted species: tobacco (Nicotiana benthamian), wheat (Triticum aestivum L.), and poplar (Populus sp.), for a total of more than 4000 data points. In tobacco we show that water stress decreased the free frequency by 15%. In wheat we could detect variations of less than 1 g in the mass of spikes. In poplar we could measure frequencies of both the whole stem and leaves. The work provides insight into new potential directions for development of phenotyping
A modular Golden Gate toolkit for Yarrowia lipolytica synthetic biology
No full textThe oleaginous yeast Yarrowia lipolytica is an established host for the bio-based production of valuable compounds and an organism for which many genetic tools have been developed. However, to properly engineer Y. lipolytica and take full advantage of its potential, we need efficient, versatile, standardized and modular cloning tools. Here, we present a new modular Golden Gate toolkit for the one-step assembly of three transcription units that includes a selective marker and sequences for genome integration. Perfectly suited to a combinatorial approach, it contains nine different validated promoters, including inducible promoters, which allows expression to be fine-tuned. Moreover, this toolbox incorporates six different markers (three auxotrophic markers, two antibiotic-resistance markers and one metabolic marker), which allows the fast sequential construction and transformation of multiple elements. In total, the toolbox contains 64 bricks, and it has been validated and characterized using three different fluorescent reporter proteins. Additionally, it was successfully used to assemble and integrate a three-gene pathway allowing xylose utilization by Y. lipolytica. This toolbox provides a powerful new tool for rapidly engineering Y. lipolytica strains and is available to the community through Addgene
Development of a cost-effective single nucleotide polymorphism genotyping array for management of greater yam germplasm collections
No full textUsing genome-wide single nucleotide polymorphism (SNP) discovery in greater yam (Discorea alata L.), 4,593 good quality SNPs were identified in 40 accessions. One hundred ninety six of these SNPs were selected to represent the overall dataset and used to design a competitive allele specific PCR array (KASPar). This array was validated on 141 accessions from the Tropical Plants Biological Resources Centre (CRB-PT) and CIRAD collections that encompass worldwide D. alata diversity. Overall, 129 SNPs were successfully converted as cost-effective genotyping tools. The results showed that the ploidy levels of accessions could be accurately estimated using this array. The rate of redundant accessions within the collections was high in agreement with the low genetic diversity of D. alata and its diversification by somatic clone selection. The overall diversity resulting from these 129 polymorphic SNPs was consistent with the findings of previously published studies. This KASPar array will be useful in collection management, ploidy level inference, while complementing accurate agro-morphological descriptions
MAMP and PRR Interaction at the Centre of Probiotic/Host Interaction
No full textProbiotic microorganisms may affect human health, partly by modulating the immune response. They are commensals, part of the natural human microbiota, or provided within fermented foods or within food supplements. As an example, some of them colonize the digestive tract at early stages of life and play a key role in the maturation of the immune system. Accordingly, a lack of implantation of these beneficial bacteria correlates with immune and inflammatory disorders, which constitute a growing health concern and are gradually understood, in the light of variations of the gut microbiota structure. Potential applications of probiotic bacteria further involve the treatment of diarrhoea caused by rotavirus, of allergy, of eczema, of irritable bowel syndrome and of inflammatory bowel diseases. The mechanisms underlying interactions between probiotic bacteria and the host thus constitute a hot topic.
Surface molecules of probiotic bacteria play a central role in these interactions. Referred to as Microbe-associated Molecular Pattern (MAMP), these key molecules are recognized by corresponding pattern recognition receptors (PRR), present at the surface of the host cells. The role of MAMPs includes adhesion and modulation of the gut associated immune system, prior to that of the systemic immune system, by mediating a host/bacteria cross-talk. MAMPs include surface proteins, glycoproteins, lipoproteins, pilins, flagellins, as well as surface associated polysaccharides. Host PRRs, which can perceive MAMPs, include Toll-like receptors (TLR), as well as the C type lectin DC-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN). They may be present at the surface of epithelial cells, and of dendritic cells.
This oral presentation will illustrate the key role of probiotics’ MAMPs through examples of bifidobacteria, lactobacilli, and of propionibacteria. It will present textbook cases spanning from molecular to in vivo studies. Scientific data acquired during the last decade indeed place interactions between MAMP and PRR at the Centre of Probiotic/Host Interaction. The corresponding mechanisms are currently elucidated
A predator-prey system: Phytoseiulus persimilis (Acari: Phytoseiidae) and Tetranychus urticae (Acari: Tetranychidae): worldwide occurrence datasets
No full textThe predator-prey system Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) and Tetranychus urticae (Koch) (Acari: Tetranychidae) represents the most studied and the most known system among the Acari. Because of the agronomical importance of the two mite species, a wealth of modelling studies investigated the interactions of the two species at the individual level. However, regional or global level works on this system are lacking, which is impeding the investigation of climate change effects on biological control effectiveness. Here we compile and geo-locate worldwide occurrences for the two species considered, based on literature, collection and field survey data. The datasets presented in this document gather most of the literature records of both species for which locality data were available for geo-referencing (1,037 for T. urticae and 126 for P. persimilis). Geo-located data from collections and field surveys including host-plants are also presented for the first time (322 for T. urticae and 65 for P. persimilis). Phytoseiulus persimilis is also reported for the first time from Kenya and La Martinique
