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Les typologies agronomiques : des outils efficaces pour évaluer rendements et performances des prairies permanentes
No full textRUNX1 safeguards the identity of the fetal ovary through an interplay with FOXL2
No full textSex determination of the gonads begins with fate specification of gonadal supporting cells into either ovarian granulosa cells or testicular Sertoli cells. This process of fate specification hinges on a balance of transcriptional control. We discovered that expression of the transcription factor RUNX1 is enriched in the fetal ovary in rainbow trout, turtle, mouse, goat and human. In the mouse, RUNX1 marks the supporting cell lineage and becomes granulosa cell-specific as the gonads differentiate. RUNX1 plays complementary/redundant roles with FOXL2 to maintain fetal granulosa cell identity, and combined loss of RUNX1 and FOXL2 results in masculinization of the fetal ovaries. At the chromatin level, RUNX1 occupancy overlaps partially with FOXL2 occupancy in the fetal ovary, suggesting that RUNX1 and FOXL2 target a common set of genes. These findings identify RUNX1, with an ovary-biased pattern conserved across species, as a novel regulator in securing the identity of ovarian supporting cells and the ovary
Identification of the master sex determining gene in Northern pike (Esox lucius) reveals restricted sex chromosome differentiation
No full textTeleost fishes, thanks to their rapid evolution of sex determination mechanisms, provide remarkable opportunities to study the formation of sex chromosomes and the mechanisms driving the birth of new master sex determining (MSD) genes. However, the evolutionary interplay between the sex chromosomes and the MSD genes they harbor is rather unexplored. We characterized a male-specific duplicate of the anti-Müllerian hormone (amh) as the MSD gene in Northern Pike (Esox lucius), using genomic and expression evidence as well as by loss-of-function and gain-of-function experiments. Using RAD-Sequencing from a family panel, we identified Linkage Group (LG) 24 as the sex chromosome and positioned the sex locus in its sub-telomeric region. Furthermore, we demonstrated that this MSD originated from an ancient duplication of the autosomal amh gene, which was subsequently translocated to LG24. Using sex-specific pooled genome sequencing and a new male genome sequence assembled using Nanopore long reads, we also characterized the differentiation of the X and Y chromosomes, revealing a small male-specific insertion containing the MSD gene and a limited region with reduced recombination. Our study depicts reveals an unexpectedly low level of differentiation between a pair of sex chromosomes harboring an old MSD gene in a wild teleost fish population, and highlights both the pivotal role of genes from the amh pathway in sex determination, as well as the importance of gene duplication as a mechanism driving the turnover of sex chromosomes in this clade
Formation FROGS juillet 2019 : Trainingon Galaxy : Metagenomics / ITS analysisin FROGS ? / Trainingon Galaxy: Statistics to explore metagenomics
No full textInfluence of protein source on the functionality and the digestibility of infant formulas
No full textInfant formulas (IF) are the only source of nutrition for infants who cannot be breastfed from their mothers. There is currently a growing interest for these sensitive products, in order to control more carefully their quality and design their composition with regard to sustainable development concern.
The aim of this work was to study how a partial substitution of dairy proteins by plant proteins influenced the functionality and the digestibility of IF.
Three IF were developed with identical composition, except that 50% of the proteins were whey proteins in the “reference IF”, and pea or faba bean proteins in the “plant IF”. Homogenization and drying steps parameters were investigated at a semi-industrial scale (IF flow rate around 100 kg.h-1). The process influence was assessed through the IF microstructure using confocal microscopy, and the protein digestibility using a dynamic in vitro digestion model.
The results showed that the emulsion structure differed depending on the protein type source that did not lead to the same stabilization of the fat droplets. It simultaneously affected the viscosity of the IF and consequently the drying parameters. Last, differences in terms of protein hydrolysis rate were observed mainly during the gastric phase compared to the end of the digestion.
This study provides new insights on the impact of the substitution of protein source in IF. It showed that plant protein sources could be good candidates for dairy proteins substitution in IF, both from a processing and nutritional point of view
Insights into the host range, genetic diversity, and geographical distribution of Jingmen viruses
No full textJingmenvirus is a recently identified group of segmented RNA viruses phylogenetically linked with unsegmented Flaviviridae viruses. Primarily identified in various tick genera originating in China, Jingmenvirus geographical distribution has rapidly expanded to cover Africa, South America, Caribbean, and Europe. The identification of Jingmen-related viruses in various mammals, including febrile humans, opens the possibility that Jingmenviruses may be novel tick-borne arboviruses. In this study, we aimed at increasing knowledge of the host range, genetic diversity, and geographical distribution of Jingmenviruses by reporting for the first time the identification of Jingmenviruses associated with Rhipicephalus microplus ticks originating in the French Antilles (Guadeloupe and Martinique islands), with Amblyomma testudinarium ticks in Lao PDR, and with lxodes ricinus ticks in metropolitan France, and from urine of Pteropus lylei bats in Cambodia. Analyses of the relationships between the different Jingmenvirus genomes resulted in the identification of three main phylogenic subclades, each of them containing both tick-borne and mammal-borne strains, reinforcing the idea that Jingmenviruses may be considered as tickborne arboviruses. Finally, we estimated the prevalence of Jingmenvirus-like infection using luciferase immunoprecipitation assay screening (LIPS) of asymptomatic humans and cattle highly exposed to tick bites. Among 70 French human, 153 Laotian human, and 200 Caribbean cattle sera tested, only one French human serum was found (slightly) positive, suggesting that the prevalence of Jingmenvirus human and cattle infections in these areas is probably low. IMPORTANCE Several arboviruses emerging as new pathogens for humans and domestic animals have recently raised public health concern and increased interest in the study of their host range and in detection of spillover events. Recently, a new group of segmented Flaviviridae related viruses, the Jingmenviruses, has been identified worldwide in many invertebrate and vertebrate hosts, pointing out the issue of whether they belong to the arbovirus group. The study presented here combined whole-genome sequencing of three tick-borne Jingmenviruses and one bat-borne Jingmenvirus with comprehensive phylogenetic analyses and high-throughput serological screening of human and cattle populations exposed to these viruses to contribute to the knowledge of Jingmenvirus host range, geographical distribution, and mammalian exposure
Similarity and competition in the agri-food trade among European mediterranean countries
No full textUsing Eurostat and OECD data on agri-food exports, this article provides a picture of the evolution in the similarity between Italian and other European Mediterranean countries’ exports, before and after the recent financial crisis. Considering different indexes, the similarity is somewhat moderate and does not vary noticeably among the indexes when considering the EU-25 market. By contrast, a strong qualitative dissimilarity is recorded in the North American market. Overall, France and Spain appear more similar to Italy and likely to compete in the same agri-food market segments. The crisis seems associated to a slight modification of the exports structure
Systèmes de production basés sur des races locales de porcs et demande sociétale pour la fourniture de biens publics : le cas de la filière Noir de Bigorre
No full textLes races locales de porcs sont fréquemment élevées dans des systèmes de production extensifs adaptés à l’environnement local et aux ressources disponibles. Ces systèmes sont généralement moins efficaces que les systèmes conventionnels mais produisent des biens publics et services pour la société (biodiversité, qualité de l’air, attractivité du paysage). La fourniture de biens publics peut ne pas être garantie par manque de reconnaissance de leur valeur économique, ou de politiques pouvant fragiliser l’avenir de ces systèmes. Des méthodes d’évaluation économique permettent de mesurer les avantages non marchands fournis par ces systèmes, par une estimation de la demande sociale envers leurs principales caractéristiques. Dans le projet européen TREASURE, une enquête d’expérimentation de choix a été réalisée pour évaluer la demande sociétale pour des caractéristiques spécifiques de la filière régionale française Noir de Bigorre (NdB), basée sur l’élevage en système extensif de porcs de race Gascon. Un questionnaire d’évaluation a été distribué, permettant l’obtention des réponses de 418 personnes, pour moitié localisées dans la région de production de la filière NdB. Les résultats montrent que 40% des répondants ne connaissent ou ne consomment pas les produits issus de cette filière. En moyenne, le consentement à payer le plus élevé est attribué pour garantir la pérennité de la race (112,37 €/foyer/an). Les répondants consentiraient à payer 42,35 € pour maintenir un nombre équivalent d’élevages de taille petite ou moyenne, et 21,86 € pour que les aliments des animaux soient produits à proximité des élevages. La disponibilité géographique et le type de points de vente des produits contribuent de façon moindre à construire leurs préférences. Ces résultats montrent qu’une demande sociale existe pour soutenir la pérennité de la race et un système de production extensif en lien avec des ressources locales.Local pig breeds are frequently raised in extensive farming systems adapted to the local environment and the resources it produces. These farming systems tend to be less efficient than their intensive counterparts, but in exchange produce goods and services for society (biodiversity, clean air, landscape attractiveness, etc.). The supply of these public goods may not be guaranteed due to a lack of recognition of their market values, and policies that ultimately can put the future of these systems at risk. Economic valuation methods can measure the non-market benefits provided by these systems as an estimate of the social demand for their key features. Within the European Union TREASURE project, a choice experiment (CE) survey was applied to assess the social demand for relevant attributes of the Noir de Bigorre (NB) French regional pork chain, based on the local Gascon pig breed in an extensive system with the character of a public good. A valuation questionnaire was administered to 418 individuals, half of them located in the production area of NB chain. Results show that almost 40% of the respondents did not know or consume products from the NB chain. On average, guaranteeing the survival of the breed achieved the highest willingness to pay (112.37 €/household/year). Respondents are willing to pay 42.35 € to maintain an equal number of small and medium farms and 21.86 € to have feedstuff produced near the farms. Geographical availability and selling places of products contribute to a lesser extent to shape their preferences. Results show that social demand does exist to support survival of the breed and its extensive production system linked to local resources
Application aux races locales européennes de la modélisation avec InraPorc des besoins nutritionnels des porcs en croissance
No full textModels such as InraPorc have been developed to simulate the growth of pigs and determine their nutrient requirements. These models have been applied largely to conventional breeds but so far not to local breeds. The aim of our study was to use InraPorc to determine nutrient requirements of growing pigs from local breeds in the H2020 European Union project TREASURE. Data on feed composition, allowance and intake, and body weight (BW) were obtained from literature reports or experiments conducted within the project. Data were used to calibrate parameters defining a growth and intake profile in InraPorc. We obtained 15 profiles from nine breeds (Alentejana, Basque, Bísara, Apulo Calabrese, Cinta Senese, Ibérico, Krškopoljska, Mangalitsa Swallow Bellied and Moravka), with one to three profiles per breed depending on experimental conditions or data source. Conditions of the studies affected calibration results. When focusing on the 40-100 kg BW range, mean protein deposition (PD) was low for all breeds, from 40.5-105.1 g/d, vs over 130 g/d in conventional breeds. The age of pigs at 40 kg BW ranged from 110-206 days, denoting different types of feeding management in addition to genetic differences. Average daily gain (ADG) curves and feed intake curves had similar shapes. Protein deposition rate was the highest in breeds with the highest ADG. Lysine requirements were largely covered in all studies and breeds, the highest requirements corresponding to the highest ADG. In all breeds, a small proportion of total body energy retention was dedicated to protein, unlike lipids. Despite some methodological limitations, this study provides an initial insight into nutrient requirements of some local breeds