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AphidInnov -Biological solutions for controlling aphid populations in protected crops
No full textAlternatives aux néonicotinoïdes Rendu des projets réunissant des contributions des projets scientifiques d'Ecophyto et du Plan National de Recherche et Innovation-betterave avec, selon les projets, les soutiens financiers de l'Office français de la biodiversité (OFB), l’Institut national de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE) et de l'Institut technique de la betterave (ITB).International audienceInundative biological control with natural enemies produced by specialist suppliers is the main alternative to insecticides in protected crops. However, major pests such as aphids are still poorly controlled, due to a lack of efficiency or availability of biological control agents that would give solutions for the disappearance of neonicotinoids. The AphidInnov project has shown, on seed cabbage, strawberry and cucumber crops, that effective parasitoid species and populations adapted to each agricultural context could be selected, taking into account the ecological specialisation of parasitoids and their genetic variation, and that effective solutions could be proposed by combining parasitoids, predators and cultural practices. The production of these biological control agents could create new business models, involving more directly professional organizations and growers
Encapsulating DHA oil promotes the digestion process in vitro and profoundly modifies the metabolism of DHA in vivo
No full textInternational audienceAn oil consisting of triglycerides highly enriched in docosahexaenoic acid (DHA), a valuable omega 3fatty acid, was encapsulated with whey proteins to form Pickering emulsions (1). The emulsion or crudeDHA oil was then cooked in an omelette. In vitro digestion showed that the bioaccessibility of DHA wassignificantly improved by the encapsulation of DHA oil. As much DHA was released during digestionafter one hour of lipase activity when the DHA oil was encapsulated, as after two hours of digestionwhen the DHA oil was not encapsulated (2). On the basis of this observation, omelettes containingencapsulated or non-encapsulated DHA oil were administered to young rats for 4 weeks to observethe metabolic effects.Firstly, the encapsulation of DHA oil tended to increase the bioavailability of DHA, although plasmalevels were not significantly different with the encapsulation of DHA oil. It also modified feedingbehaviour by stimulating rodent chow consumption. This effect promoted the animal’s growth.Secondly, administration of DHA oil significantly altered the profiles of oxygenated fatty acidderivatives, drastically reducing the overall levels of omega-6-derived oxylipins in the plasma and theheart, but not in the brain (3). This effect was greatly accentuated when the DHA oil was encapsulated.On the other hand, DHA-derived oxylipins were increased overall in the heart and brain, even more sowhen the DHA oil was encapsulated.Thirdly, administration of DHA oil also modified the profiles of endocannabinoid derivatives of fattyacids (4). Endocannabinoids and N-acylethanolamides were greatly reduced in plasma and brain, butwithout the impact of DHA encapsulation. The heart showed a different pattern, with an increase inDHEA from DHA, specifically when DHA oil was encapsulated.In conclusion, these results show that modifying the food structure allows a nutrient to be delivereddifferently, and thus to modify not only its digestion process but also its subsequent metabolism. Theyalso highlight the fact that the impact of the food structure may not really influence the levels of thetarget nutrient in the body, but may completely affect its metabolism into lipid derivatives, which mustbe investigated and quantified
The in vitro dynamic digestion : a suitable model to mimic the in vivo digestion of infant foods in terms of food deconstruction and protein hydrolysis
No full textInternational audienceHuman infants are preferably fed human milk (HM), but a majority still receive infant formula (IF) as a HM substitute. Optimization of IF is still required to improve HM biomimetics, including digestion behavior biomimetics. While this can be studied in vivo, such experiments have to be reduced and appropriate in vitro models are needed. The present study aimed to compare food deconstruction and protein digestion of HM vs. IF using two infant digestion models, the mini-piglet and the in vitro dynamic gastrointestinal system (DIDGI®). Mini-piglets (Yucatan) were fed either a mature HM (n=9) or a standard IF (n=9) during 6 days. Piglet digesta were collected along the digestive tract 30 min after the last meal. The same foods were digested in triplicate using a term infant in vitro dynamic model with regular digesta sampling along time. Microstructure (confocal microscopy and laser diffraction) and protein digestion (SDS-PAGE, hydrolysis degree, peptidomics) were investigated in both digestion models. Data were statistically analyzed thanks to ANOVA and multidimensional analyses (hierarchical classification and multiple factor analyses). The microstructure of the digesta differed between HM and IF in a similar manner in vitro and in vivo along digestion. The meal dilution and emptying were similar between both digestion models, with a faster emptying for HM. Proteolysis, as investigated by SDS-PAGE, were similar between digestion models, with a lower hydrolysis level for HM caseins. Peptide mapping along the sequence of the major proteins was well correlated between models, particularly in the stomach and the proximal jejunum (r > 0.6). Similar result was found for bioactive peptide release. The ratio between bioaccessibility (in vitro) and bioavailability (in vivo) of amino acids was high (50-80%) at the cleavage sites of the pancreatic enzymes, more precisely for Arg, Tyr, Lys, Phe and Leu, but was much lower for the other amino acids (<30%). In overall, the in vitro dynamic gastrointestinal digestion model well predicted the in vivo digestion of HM and IF, particularly for protein hydrolysis, peptidomics and food deconstruction, while further improvement is needed to better correlate bioaccessibility and bioavailability
Infrared Thermography of Teat in French Dairy Alpine Goats: A Promising Tool to Study Animal–Machine Interaction during Milking but Not to Detect Mastitis
No full textInternational audienceThere is a need to develop tools for mastitis management in goats and to measure the effects of milking machines on teats. Infrared thermography (IRT), as shown in cows, was a good candidate for early mastitis detection and focusing on milking equipment and settings implicated in potential problems. The aim of this study was to test IRT to detect udder inflammation and the effects of mechanical milking on teats in relation to inflammation status, udder balance, and teat shape in Alpine goats. IRT spectra were compared before and after milking in 551 goats from three commercial herds compared to their individual SCC (somatic cell count). We found no regression or trend between logSCC and IRT measurement or response to milking, even in highly inflamed goat udders. The effect of milking was significant (p < 0.05) with global temperature reduction after milking, but differences were seen between teat parts and unbalanced half udders. The highest reduction in skin temperature was observed at the teat orifice (−1.06 ± 0.05) and the lowest at the teat barrel (−0.37 ± 0.05). The teats with long barrels showed more IRT reactions, which clearly indicates poor adaptation to the liners used. In conclusion, the IRT was not able to detect mastitis, but it is a good tool to diagnose the effects of the milking machine in order to adapt milking equipment and settings to the goats and improve their welfare
How does the social economy contribute to social and environmental innovation? Evidence of direct and indirect effects from a European survey
No full textInternational audienceThis study represents the first empirical attempt to conduct a cross-country comparison of social economy (SE) enterprises with other enterprises in the development of social and environmental innovation. Using data from a European survey with >16,000 respondents, we estimate a bivariate probit model with correlated random effects to identify the direct and indirect effects of the SE on social and environmental innovation. We demonstrate that the primary impact of SE enterprises on environmental innovation is through their influence on other enterprises. We also identify the specific levers of innovation in SE and non-SE enterprises. Our empirical findings are consistent with previous research on the SE as a laboratory of innovation and a yardstick for transformative change. Our original findings regarding contextual effects highlights a strong implication advocating public policies to promote SE for its assumed benefits as well as the tendency of SE to foster innovation within non-SE enterprises
Dark side of the honeymoon: reconstructing the Asian x European rose breeding history through the lens of genomics
No full textInternational audienceAbstract Roses have a specific symbolic charge in Western cultural heritage, often used as a metaphor for love and romance. Despite its ancient cultivation, the passion for the phenotypic diversity of roses is relatively recent, dating back to the early 19 th century. During that century, the number of rose varieties has increased exponentially from roughly 100 to 8,000, in such a way that this period can be considered as the golden age for rose breeding. To retrace the history of rose breeding in Europe and shed new light on genetic changes during this period, we collected large phenotypic and genetic data from 204 accessions, including botanical roses and varieties bred between 1800 and 1910. We also used whole-genome sequences from 32 accessions as an extra resource. The genetic makeup of roses is remarkably consistent with a temporal shift from a historical European to a near-Asian genetic background within a few generations. Our analyses are consistent with a substantial erosion of the genetic diversity during this period, both because of the greater contribution of the Asian genepool - a less genetically diverse group - and of specific genomic footprints of selection, in particular regarding the extension of the blooming period. Thanks to this study, we have generated the largest GWAS catalog for roses to date, which can be used as a tool for future rose breeding programs. We particularly discuss the crucial importance of preserving ancient rose collections to safeguard genetic diversity and ensure a sustainable breeding for the long-term
Induction of common bean OVATE Family Protein 7 (PvOFP7) promotes resistance to common bacterial blight
No full textCommon bacterial blight of bean (CBB) is a devastating seed-transmitted disease caused by Xanthomonas phaseoli pv. phaseoli and Xanthomonas citri pv. fuscans on common bean (Phaseolus vulgaris L.). The genes responsible for CBB resistance are largely unknown. moreover, the lack of reproducible and universal transformation protocol limits the study and improvement of genetic traits in common bean. We produced X. phaseoli pv. phaseoli strains expressing artificially-designed Transcription-Activator Like Effectors (dTALEs) to target 14 candidate genes and performed in planta assays in a susceptible common bean genotype to analyse if the transcriptional induction of these genes could confer resistance to CBB. Induction of PvOFP7, PvAP2-ERF71 and PvExpansinA17 resulted in CBB symptom reduction. In particular, PvOFP7 induction led to strong symptom reduction, linked to reduced bacterial growth in planta at early colonisation stages. RNA-Seq analysis revealed up-regulation of cell wall formation and primary metabolism, and major downregulation of Heat Shock Proteins. Our results demonstrate that PvOFP7 is contributes to CBB resistance, and underline the usefulness of dTALEs for highlighting genes of quantitative activity
One-shot technology for 3D imaging of large animals: perspectives for ruminant management
No full textInternational audienceIn numerous systems of animal production, there is increasing interest in the use of 3D imaging technology on farms for its ability to easily and safely measure traits of interest on living animals. With this information, it is possible to evaluate multiple morphological indicators of interest, either directly or indirectly, and follow them through time. Several tools for this purpose were developed, but one of their main weaknesses was their sensitivity to light and animal movement, which limited their potential for large-scale application on farms. To address this, a new device, called Deffilait3D and based on depth camera technology, was developed. In tests on 31 Holstein dairy cows and 13 Holstein heifers, the values generated for most measured indicators were highly repeatable and reproducible, with coefficients of variation lower than 4%. A comparison of measurements obtained from both Deffilait3D and previous validated system, called Morpho3D, revealed a high degree of similarity for most selected traits, e.g., less than 0.2% variation for animal volume and 1.2% for chest depth, with the highest degree of difference (8%) noted for animal surface area. Previously published equations used to estimate body weight with the Morpho3D device were equally valid using Deffilait3D. This new device was able to record 3D images regardless of the movement of animals and it is affected only by direct daylight. The on-going step is now to develop methods for automated analysis and extraction from images, which should enable the rapid development of new tools and potentially lead to the large-scale adoption of this type of device on commercial farms
Partie 1. Travailler avec les ruminants
No full textNational audienceLe Manuel d'expérimentation animale - La pratique, rédigé par des acteurs du monde scientifique et de la recherche expérimentale, vient en complément du Manuel d'expérimentation animale - Principes généraux qui aborde principalement les questions d'éthique et la réglementation du travail avec les animaux utilisés à des fins scientifiques. Les 2 volumes couvrent tous les thèmes développés lors des formations réglementaires permettant d'acquérir les compétences les autorisant à travailler avec les animaux, quelle que soit l'espèce, et vient combler un manque pour la communauté scientifique. Complet et pratique, ce volume organisé en 2 tomes, rassemble les connaissances relatives aux principales espèces impliquées dans la recherche expérimentale et décrit les gestes pratiques et les observations de terrain des différents acteurs de la recherche. Les rongeurs, lapins, carnivores, oiseaux sont traités dans le tome 1 ; les ruminants, primates non humains, porcs, espèces aquacoles vertébrées, céphalopodes sont traités dans le tome 2. L'ouvrage servira de référence aux chercheurs, vétérinaires, techniciens et animaliers dans leur pratique quotidienne. Ils pourront s'y référer en termes de bonnes pratiques et y trouver des réponses aux interrogations concernant le travail avec les différentes espèces : origine, anatomie et physiologie, comportement et enrichissements, reconnaissance des signes de souffrance, paramètres de l'environnement, gestion des animaux dans l'animalerie, zootechnie, gestes et procédures de base
Overexpression of an apple broad range agglutinating lectin does not promote in planta resistance to fire blight and bacterial wilt
No full textInternational audienceLectins, a large group of proteins present in all kingdoms of life can bind reversibly to glycans. The roles of plant lectins are diverse and include resistance to biotic or abiotic stress, notably bacterial resistance. A gene family encoding amaranthin-like lectins termed MdAGGs in apple (Malus domestica) has been identified to be overexpressed upon treatment with the plant resistance inducer acibenzolar-S-methyl (ASM) which promotes enhanced resistance to the fire blight disease caused by Erwinia amylovora (Ea). In this study, we first screened the ability of purified MdAGG10 to agglutinate bacterial cells in vitro among a range of bacterial species. Several bacterial species, either Gram positive or negative, either plant- or human-pathogens were found to be agglutinated by MdAGG10 in acidic conditions. Apple and Arabidopsis lines constitutively overexpressing MdAGG10 were generated and evaluated for their resistance to, respectively, Ea and Ralstonia solanacearum, both plant pathogens that were found in our screening. Despite MdAGG10 protein accumulated in tissues of both apple and Arabidopsis lines, they remained susceptible to their respective pathogens. Interestingly, in vitro agglutination of Ea by MdAGG10 did not impair bacterial growth, suggesting that other plant molecules are involved in the resistance to fire blight triggered after an ASM treatment