49 research outputs found

    Genetic parameters of feeding behaviour and performance traits in group-housed Large White and French Landrace growing pigs

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    Data on feeding behaviour of 3 710 group-housed and ad libitum fed growing pigs were recorded using ’Acema 48’ electronic feed dispensers. Genetic parameters for six feeding behaviour criteria and the main production traits routinely recorded in French central test stations (three ’boar’ traits and three ’sib’ traits) were estimated in two breeds (Large White and French Landrace) using a multiple trait animal model DF-REML procedure. Heritability estimates for feeding behaviour criteria ranged from 0.36 to 0.54 and were markedly higher than that for the food conversion ratio (0.20). Heritability of daily feed intake was 0.42 in both breeds, whereas heritabilities of rate of feed intake, feed intake per meal and time per meal were slightly higher (0.45-0.54). Daily feed intake showed a very close genetic correlation (around 0.85) with average daily gain but also unfavourable genetic correlations with ultrasonic backfat thickness (around 0.5) and lean percentage (around -0.4). Daily feed intake was genetically independent of food conversion ratio, whereas average daily gain showed a favourable genetic correlation (around -0.35) with that trait. Among the feeding behaviour criteria, feed intake per meal and rate of feed intake showed the highest genetic correlations with daily feed intake (around 0.5) and average daily gain (around 0.4). They also showed moderately unfavourable genetic correlations with ultrasonic backfat thickness (around 0.25) and carcass lean percentage (around -0.25) and seemed to be genetically independent of food conversion ratio. The value of including a trait relating to feed intake pattern among traits selected for is discussed on the basis of this set of genetic parameters.Les données de comportement alimentaire de 3 710 porcs en croissance élevés en groupes et alimentés à volonté ont été récoltées à l’aide de distributeurs automatiques d’aliment «Acema 48». Les paramètres génétiques de six critères de comportement alimentaire et des principaux caractères de production mesurés en routine dans les stations publiques de contrôle des performances (trois caractères « candidats » et trois caractères « collatéraux») ont été estimés dans deux races (Large White et Landrace français) à l’aide de la méthode du maximum de vraisemblance restreinte (REML) appliquée à un modèle animal multicaractère. Les héritabilités des critères de comportement alimentaire sont comprises entre 0,36 et 0,54, et sont nettement supérieures à celle de l’indice de consommation (0,20). L’héritabilité de la consommation moyenne journalière est de 0,42 dans chacune des deux races tandis que celles de la vitesse d’ingestion, de la consommation moyenne par repas ou de la durée des repas sont légèrement plus élevées (0,45-0,54). La consommation moyenne journalière présente une corrélation génétique très élevée (de l’ordre de 0,85) avec le gain moyen quotidien mais aussi des corrélations génétiques défavorables avec l’épaisseur de lard dorsal (de l’ordre de 0,5) et le pourcentage de muscle (de l’ordre de - 0,4). La consommation moyenne journalière est génétiquement indépendante de l’indice de consommation tandis que le gain moyen quotidien présente une corrélation génétique favorable (de l’ordre de -0,35) avec ce caractère. Parmi les critères de comportement alimentaire, la consommation moyenne par repas et la vitesse d’ingestion sont les plus liées génétiquement à la consommation moyenne journalière (environ 0,5) et au gain moyen quotidien (environ 0,4). Ces critères présentent également des corrélations génétiques modérément défavorables avec l’épaisseur de lard dorsal (environ 0,25) et le pourcentage de muscle (environ -0,25) et semblent être génétiquement indépendants de l’indice de consommation. L’inclusion possible d’un critère de comportement alimentaire parmi les caractères sélectionnés est discutée sur la base de cet ensemble de paramètres génétiques

    Ensuring that the Sentinel-3A altimeter provides climate-quality data

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    Sentinel-3A, launched in February 2016, is part of ESA's long-term commitment to climate monitoring from space. Its suite of instruments for measuring surface topography includes a Microwave Radiometer (MWR) and SRAL, the first delay-Doppler instrument to provide global coverage. SRAL promises fine spatial resolution and reduced noise levels that should together lead to improved performance over all Earth surfaces. The Sentinel-3 Mission Performance Centre (S3MPC) has been developing the methodology to evaluate the accuracy of retrievals, monitor any changes and develop solutions to known problems. The S3MPC monitors internal temperatures, path delays and the shape of the generated pulses to assess the instruments health. The MWR records over known reference surfaces are compared with those from other spaceborne instruments. Over the ocean the SRAL's return pulses are analysed to give range to the sea surface, wave height and signal strength (which can be interpreted as wind speed). The metocean data are regularly contrasted with records from in situ measurements and the output from meteorological models, which rapidly highlights the effects of any changes in processing. Range information is used to give surface elevation, which is assessed in three ways. First, flights over a dedicated radar transponder provide an estimate of path delay to within ~10 mm (r.m.s.). Second, measurements are compared to GPS- levelled surfaces near Corsica and over Lake Issyk-kul. Third, there are consistency checks between ascending and descending passes and with other missions. Further waveform analysis techniques are being developed to improve the retrieval of information over sea-ice, land-ice and inland waters

    The Sentinel-3 Mission Performance Center

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    As part of the Sentinel-3 mission and in order to ensure the highest quality of products, ESA in cooperation with EUMETSAT has set up the Sentinel-3 Mission Performance Centre (S-3 MPC). This facility is part of the Payload Data Ground Segment (PDGS) and aims at controlling the quality of all generated products, from L0 to L2. The S-3 MPC is composed of a Coordinating Centre (CC), where the core infrastructure is hosted, which is in charge of the main routine activities (especially the quality control of data) and the overall service management. Expert Support Laboratories (ESLs) are involved in calibration and validation activities and provide specific assessment of the products (e.g., analysis of trends, ad hoc analysis of anomalies, etc.). The S-3 MPC interacts with the Processing Archiving Centres (PACs) and the Marine centre at EUMETSAT

    Copernicus Cal/Val Solution - D3.3 - Copernicus operational FRM network and supersites

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    - Identify measurement gaps, considering the existing ground-based Cal/Val measurement campaigns and networks (as outcome from Tasks 2.4 and 2.5) - Identify rationalization and optimization pathways: e.g., use of common instrumentation, protocols, and standards across sites; cross-Sentinel use of generic measurements; “supersite” approaches to minimize maintenance costs, as well as possible synergies with other European or international programs - Define a minimum set of requirements for a “Copernicus” label for measurement sites, addressing measurement protocols, documentation, availability, data policy; define a certification process - Principles and need to evaluate degree of equivalence between individual networks and sites (inter-comparisons) and for other comparison measurement

    Sentinel-3 Mission Performance Centre: Ensuring a high-quality altimetric dataset

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    Sentinel-3A is scheduled for launch in Oct. 2015, with Sentinel-3B to follow 18 months later. Together these missions are to take oceanographic remote-sensing into a new operational realm. To achieve this a large number of processing, calibration and validation tasks have to be applied to their data in order to assess for quality, absolute bias, short-term changes and long-term drifts. ESA has funded the Sentinel-3 Mission Performance Centre (S3MPC) to carry out this evaluation on behalf of ESA and EUMETSAT. The S3MPC is run by a consortium led by ACRI [1] and this paper describes the work on the calibration/validation (cal/val) of the Surface Topography Mission (STM), which is co-ordinated by CLS and PML

    Globcurrent: Sentinel-3 synergy in action

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    The ESA Data User Element (DUE) funded GlobCurrent project (http://www.globcurrent.org) aims to: (i) advance the quantitative estimation of ocean surface currents from satellite sensor synergy; and (ii) demonstrate impact in user-led scientific, operational and commercial applications that, in turn, will improve and strengthen the uptake of satellite measurements. Today, a synergetic approach for quantitative analysis can build on high-resolution imaging radar and spectrometer data, infrared radiometer data and radar altimeter measurements. It will further integrate Sentinel-3 in combination with Sentinel-1 SAR data. From existing and past missions, it is often demonstrated that sharp gradients in the sea surface temperature (SST) field and the ocean surface chlorophyll-a distribution are spatially correlated with the sea surface roughness anomaly fields at small spatial scales, in the sub-mesocale (1-10 km) to the mesoscale (30-80 km). At the larger mesoscale range (>50 km), information derived from radar altimeters often depict the presence of coherent structures and eddies. The variability often appears largest in regions where the intense surface current regimes (>100 - 200 km) are found. These 2-dimensional structures manifested in the satellite observations represent evidence of the upper ocean (~100-200 m) dynamics. Whereas the quasi geostrophic assumption is valid for the upper ocean dynamics at the larger scale (>100 km), possible triggering mechanisms for the expressions at the mesoscale-to-submesoscale may include spiraling tracers of inertial motion and the interaction of the wind-driven Ekman layer with the quasi-geostrophic current field. This latter, in turn, produces bands of downwelling (convergence) and upwelling (divergence) near fronts. A regular utilization of the sensor synergy approach with the combination of Sentinel-3 and Sentinel-1 will provide a highly valuable data set for further research and development to better relate the 2-dimensional surface expressions and the upper ocean dynamics

    Copernicus Cal/Val Solution - D3.1 Recommendations for R&D activities on Instrumentation Technologies

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    The Document identifies the gaps in instrumentation technologies for pre-flight characterisation, onboard calibration and Fiducial Reference Measurements (FRM) used for calibration and validation (Cal/Val) activities for the current Copernicus missions. It also addresses the measurement needs for future Copernicus missions and gives a prioritised list of recommendations for R&D activities on instrumentation technologies. Four types of missions are covered based on the division used in the rest of the CCVS project: optical, altimetry, radar and microwave and atmospheric composition. It also gives an overview of some promising instrumentation technologies in each measurement field for FRM that could fill the gaps for requirements not yet met for the current and future Copernicus missions and identifies the research and development (R&D) activities needed to mature these example technologies. The Document does not provide an exhaustive list of all the new technologies being developed but will give a few examples for each field to show what efforts are being made to fill the gaps. None of the examples is promoted as the best possible solutions. The selection is based on the authors' knowledge during the preparation of the Document. The information included is mainly collected from the deliverables of work packages 1 and 2 in the CCVS project. The new technologies are primarily from the interviews with various measurement networks and campaigns carried out in tasks 2.4 and 2.5. Reference documents can be found in section 1.3

    Comparison of Muscle Transcriptome between Pigs with Divergent Meat Quality Phenotypes Identifies Genes Related to Muscle Metabolism and Structure

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    Background: Meat quality depends on physiological processes taking place in muscle tissue, which could involve a large pattern of genes associated with both muscle structural and metabolic features. Understanding the biological phenomena underlying muscle phenotype at slaughter is necessary to uncover meat quality development. Therefore, a muscle transcriptome analysis was undertaken to compare gene expression profiles between two highly contrasted pig breeds, Large White (LW) and Basque (B), reared in two different housing systems themselves influencing meat quality. LW is the most predominant breed used in pig industry, which exhibits standard meat quality attributes. B is an indigenous breed with low lean meat and high fat contents, high meat quality characteristics, and is genetically distant from other European pig breeds. Methodology/Principal Findings: Transcriptome analysis undertaken using a custom 15 K microarray, highlighted 1233 genes differentially expressed between breeds (multiple-test adjusted P-value,0.05), out of which 635 were highly expressed in the B and 598 highly expressed in the LW pigs. No difference in gene expression was found between housing systems. Besides, expression level of 12 differentially expressed genes quantified by real-time RT-PCR validated microarray data. Functional annotation clustering emphasized four main clusters associated to transcriptome breed differences: metabolic processes, skeletal muscle structure and organization, extracellular matrix, lysosome, and proteolysis, thereb

    Facteurs de variation génétiques de la prise alimentaire chez le porc en croissance : le point des connaissances

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    National audienceThe aim of this paper is to investigate the different genetic factors that influence feed intake, previously to study the possible inclusion of a feeding behaviour criterion in the selection objective. Breed is an important souce of variation of feed intake (differences of 10 to 20 %). In addition, breed could influence meal characteristics (frequency, size, duration). Heterosis estimates for daily feed intake (5 to 10 % of the parental mean) are similar to those reported for growth rate and feed efficiency. Feed intake differences between the three genotypes at the Hal locus range from 5 to 15 %. The average of estimates for feed intake heritability in real ad libitum feeding conditions is 0.32. The average genetic correlations between daily feed intake on the one hand, and average daily gain, food conversion ratio and carcass lean content on the other hand, are around 0.75, 0.40 and -0.45, respectively. The possible consequences of including appetite in the selection objective are discussed on the basis of these average genetic parameters.L’objectif de cet article est d’examiner les différents facteurs génétiques qui influencent la prise alimentaire, avant d’étudier la possibilité d’inclure un critère de comportement alimentaire dans les objectifs de sélection. Le type génétique peut entraîner des variations importantes (10 à 20 %) du niveau de consommation et influencer les caractéristiques (fréquence, taille, durée) des repas. Les valeurs d’hétérosis pour la consommation moyenne journalière (5 à 10 % de la moyenne parentale) sont du même ordre de grandeur que celles rapportées pour la vitesse de croissance ou l’efficacité alimentaire. Les écarts de consommation entre les trois génotypes pour le gène Hal varient entre 5 et 15 %. La moyenne des estimées pour l’héritabilité de la consommation alimentaire en conditions réelles d’alimentation ad libitum est 0,32. Les corrélations génétiques moyennes entre la consommation moyenne journalière d’une part, le gain moyen quotidien, l’indice de consommation et le taux de muscle d’autre part, sont respectivement de l’ordre de 0,75, 0,40 et -0,45. Les répercussions économiques éventuelles de la prise en compte de l’appétit dans les objectifs de sélection sont discutées sur la base de ces paramètres génétiques moyens
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