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See detailAn approach to automated spiral eddy detection in SAR images
Karimova, Svetlana ULiege

in Proc. IGARSS 2017 (2017, July)

Satellite derived synthetic aperture radar (SAR) imagery frequently contains manifestations of coherent structures (eddies) of different spatial scale. However, due to strong dependence of SAR imaging on ... [more ▼]

Satellite derived synthetic aperture radar (SAR) imagery frequently contains manifestations of coherent structures (eddies) of different spatial scale. However, due to strong dependence of SAR imaging on the near-surface wind speed during the SAR acquisition, such eddy manifestations can be at great extent masked by the signatures of other, mostly atmospheric, phenomena. In the present paper, we propose a method for an automated detection of eddy manifestations visualized by surfactant films presenting on the water surface. The method proposed based on sequential application of image transformations aimed at masking atmospheric phenomena and highlighting the surfactant filaments manifesting eddies in SAR images. Thus extracted dark patches are being fitted by circles, and close co-location of several such circles would be considered an eddy manifestation. [less ▲]

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See detailConclusions des 53e Journées de Fanjeaux
George, Philippe ULiege

Conference given outside the academic context (2017)

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See detailMartre, muscardin, chat sylvestre et compagnie
Schockert, Vincianne ULiege; Libois, Roland ULiege; Lambinet, Clotilde ULiege

in Blerot, Philippe (Ed.) Le grand livre de la forêt (2017)

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See detailLe système semencier en question
Hecquet, Corentin ULiege; Stassart, Pierre M ULiege

Article for general public (2017)

Les enjeux de biodiversité, le procès contre l’association Kokopelli, une demande accrue d’une alimentation saine et respectueuse, le désir d’autonomie d’agricul- teurs nourrissent les interrogations ... [more ▼]

Les enjeux de biodiversité, le procès contre l’association Kokopelli, une demande accrue d’une alimentation saine et respectueuse, le désir d’autonomie d’agricul- teurs nourrissent les interrogations par rapport au fonctionnement du système se- mencier. Cet article dépeint le système semencier européen et les critiques dont il fait l’objet. Ne sont pas abordés ici la réglementation phytosanitaire1, la certification de certaines espèces ni les OGM2. La législation européenne concernant la circula- tion des semences est régie par une dizaine de directives. Les droits de propriétés intellectuelles sur les semences sont régis, quant à eux, par les conventions au sein de l’Union internationale pour la Protection des Obtentions Végétales (UPOV) et au niveau européen, l’Office Communautaire des Variétés Végétales (OCVV) soutient les mécanismes de Certification d’Obtentions Végétales (COV). [less ▲]

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See detailAntarctic sea ice trophic status
Van der Linden, Fanny ULiege; Moreau, Sébastien; Champenois, Willy ULiege et al

Poster (2017, July)

The sea ice ecosystem is characterized by steep gradients in temperature, salinity, light and nutrient availability. Despite these challenging environmental conditions, sea ice provides a dynamic habitat ... [more ▼]

The sea ice ecosystem is characterized by steep gradients in temperature, salinity, light and nutrient availability. Despite these challenging environmental conditions, sea ice provides a dynamic habitat for diverse communities of microorganisms. These communities include a wide variety of organisms from different taxonomic groups such as algae, bacteria, heterotrophic protists, fungi as well as viruses [Horner et al., 1992; Deming, 2010; Thomas and Dieckmann, 2010; Poulin et al., 2011]. In the frame of the YROSIAE project (Year-Round survey of Ocean-Sea-Ice-Atmosphere Exchanges), carried out at Cape Evans in McMurdo Sound (Antarctica) from Nov. 2011 to Dec. 2012, ice cores, seawater, and brine material were collected at regular time intervals. Physical properties (salinity, temperature, texture) and biogeochemical parameters (pCO2, dissolved inorganic carbon, total alkalinity, chlorophyll-a, macro-nutrients) were analysed. We will here particularly consider changes inused dissolved inorganic carbon (DIC) and chlorophyll-a (chl-a) , used as a proxiesy of net community production and autotrophic biomass, respectively. A high spatial and temporal variability in ice algal biomass and DIC evolution were observed. From spring, very high chl-a concentrations (>2400μg.L^(-1)) were observed at the bottom of the ice, a common feature of land fast ice in the McMurdo Sound. This suggests high primary production. However Strikingly, , at the same time, nutrients at the bottom of the ice increased significantly suggesting high heterotrophyremineralisation. In the middle of the ice column, evolution of DIC is was marked by a succession of autotrophic and heterotrophic phases. The overall increase of DIC suggests that the ice interior was rather heterotroph. Such sea ice system should expel CO2. Yet, strong under-saturation in CO2 and DIC depletion appeared at the ice surface, suggesting that sea ice was taking up CO2 from the atmosphere. On the whole, land fast sea ice in McMurdo Sound appears as a puzzling ecosystem. It is able to support elevated growth of autotrophic organisms at the bottom, but still appears to be heterotrophicin parallel to high remineralization, while the top of the ice appears to be rather heterotrophic but stilland able to pump CO2 from the atmosphere. [less ▲]

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See detailN2O production and cycling within Antarctic sea ice
Kotovitch, Marie ULiege; Tison, J.-L.; Fripiat, François ULiege et al

Poster (2017, July)

Nitrous oxide (N2O) is a potent greenhouse gas that has a lifetime of 114 years in the atmosphere and a global warming potential 300 time higher than that of CO2. However there are still large ... [more ▼]

Nitrous oxide (N2O) is a potent greenhouse gas that has a lifetime of 114 years in the atmosphere and a global warming potential 300 time higher than that of CO2. However there are still large uncertainties and gaps in the understanding of the N2O cycle in polar oceans and particularly associated to sea ice. Sources and sinks of N2O are therefore poorly quantified. To date, only one study by Randall et al. 2012 present N2O measurements in sea ice. They pointed out that sea ice formation and melt has the potential to generate sea-air or air-sea fluxes of N2O, respectively. The main processes (except the transport processes) involved in the N2O cycle within the aquatic environment are nitrification and denitrification. Recent observations of significant nitrification in Antarctic sea ice shed a new light on nitrogen cycle within sea ice. It has been suggested that nitrification supplies up to 70% of nitrate assimilated within Antarctic spring sea ice. Corollary, production of N2O, a by-product of nitrification, can potentially be significant. Our recent studies in Antarctic land fast ice in McMurdo Sound, confirmed this suggestion, where N2O release to the atmosphere was estimated to reach 4µmol.m-2.yr-1. But this assessment is probably an underestimation since it only accounts for dissolved N2O while a significant amount of N2O is likely to occur in the gaseous form like N2, O2 and Ar. We will then address the new tools to measure the bulk concentration of N2O (dissolved and gaseous) in sea ice, and the production of N2O by sympagic microorganisms - what process is dominant and how much N2O is produced - based on the first time series of N2O measurement in sea ice. The determination of the isotopic composition of N2O using cavity enhanced laser absorption spectroscopy technique (Off-axis ICOS) will allow us to determine the origin of these processes. [less ▲]

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See detailWhere does the methane entrapped in Antarctic sea ice come from?
Jacques, C.; Sapart, Célia Julia ULiege; Carnat, G. et al

Poster (2017, July)

Methane (CH4) atmospheric concentrations have increased by a factor of 2.5 since the beginning of the Industrial Era, mainly because of anthropogenic activities. However, between 1999 and 2006, CH4 growth ... [more ▼]

Methane (CH4) atmospheric concentrations have increased by a factor of 2.5 since the beginning of the Industrial Era, mainly because of anthropogenic activities. However, between 1999 and 2006, CH4 growth rate declined to a near-zero level, suggesting that an equilibrium had been reached. But, from 2007 on, atmospheric concentrations underwent a renewed growth, implying major ongoing changes in the CH4 global budget (Nisbet et al., 2016). These changes challenge our understanding on the contribution of existing sources, and in particular natural sources. Sea ice can strongly affect emissions of CH4 from the ocean, but the precise mechanisms are not well understood. Sea ice has long been considered as an inert and impermeable barrier, but recent studies have highlighted the existence of gas fluxes at the atmosphere-sea ice and sea ice-seawater interfaces (Kort et al., 2012; He et al., 2013; Zhou et al., 2014; Sapart et al., 2016). However, these fluxes are to date poorly understood and quantified. To improve future climate projections, we aim to investigate the control exerted by sea ice on the CH4 atmospheric budget. To unravel the impacts of the Antarctic sea ice physical environment on biogeochemical cycles, the AWECS (Antarctic Winter Ecosystem Climate Study) expedition was conducted between the 8th of June and the 12th of August 2013 in the Weddell Sea. Such an expedition provides a rare opportunity to obtain insights on the behaviour of sea ice during winter. Ice cores specifically dedicated to the investigation of gas dynamics were collected at ten different stations. In order to determine CH4 formation and removal pathways in sea ice, we used concentration and stable isotope analysis, which can help to distinguish different processes. Here, we present and discuss our first results of the isotopic composition of CH4 (δ13C and δ D) on sea ice cores from the Weddell Sea and the Ross Ice Shelf. This new dataset will help to determine the origin of the CH4 entrapped in Antarctic sea ice and its potential impact on the current and future atmospheric CH4 budget. [less ▲]

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See detailMultiple uprising invasions of Pelophylax water frogs, potentially inducing a new hybridogenetic complex
Dufresne, Christophe; Denoël, Mathieu ULiege; Di Santo, Lionel et al

in Scientific Reports (2017), 7

The genetic era has revolutionized our perception of biological invasions. Yet, it is usually too late to understand their genesis for efficient management. Here, we take the rare opportunity to ... [more ▼]

The genetic era has revolutionized our perception of biological invasions. Yet, it is usually too late to understand their genesis for efficient management. Here, we take the rare opportunity to reconstruct the scenario of an uprising invasion of the famous water frogs (Pelophylax) in southern France, through a fine-scale genetic survey. We identified three different taxa over less than 200 km2: the autochthonous P. perezi, along with the alien P. ridibundus and P. kurtmuelleri, which have suddenly become invasive. As a consequence, the latter hybridizes and may now form a novel hybridogenetic complex with P. perezi, which could actively promote its replacement. This exceptional situation makes a textbook application of genetics to early-detect, monitor and understand the onset of biological invasions before they pose a continental-wide threat. It further emphasizes the alarming rate of amphibian translocations, both at global and local scales, as well as the outstanding invasive potential of Pelophylax aliens. [less ▲]

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See detailNew models to predict microcarriers just-suspended state in bioreactors for stem cell culturel
Loubière, Céline; Olmos, Eric; Guedon, Emmanuel et al

Conference (2017, July)

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See detailWEATHERING ON THE DEVONIAN SLATES AND CHARACTERIZATION OF A BENTONITE LAYER IN THE WESTERWALD (GERMANY)
Fontaine, François ULiege; Hamaekers, Helen; Hoffmann, Andreas et al

Conference (2017, July)

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of ... [more ▼]

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian rocks. During the Miocene, intense volcanic activities led to a large basalt cover, protecting the clays from the erosion. The two main goals of this study are first to improve the knowledge on the weathering processes of the Devonian slates that led to the current setting of those clay deposits by studying the mineralogical and chemical composition of the clays with depth. The second goal is to characterize a bentonite layer underneath the Miocene basalt cover using quantitative X-ray diffraction, chemical analysis, BET, cation exchange capacity and scanning electron microscope. A 20 meter deep quarry mining the Devonian bedrock in southern Westerwald has been sampled on its entire depth. The XRD results show no significant variations of the mineralogy with depth, except for the phyllosilicates. The minerals of the < 2 μm fraction are illite, kaolinite, smectite and mixed-layers minerals (vermiculite-chlorite and illite-chlorite). The proportions of the minerals in the mixed-layers chlorite-vermiculite vary with depth. At the bottom of the quarry, the proportion of vermiculite is very low while in the top, the proportion of vermiculite is higher. This is explained by the degree of the weathering, logically more intense at the top of the quarry. Trace elements compositions are currently being investigated. A 3 meter thick greenish to brownish bentonite layer has been found in the eastern part of the Westerwald region. The XRD performed on different samples of this bentonite shows a relatively heterogeneous composition: montmorillonite (60-80%), kaolinite (5-12%), illite (0-7%), goethite (2-15%), talc (0-10%), K-feldspars (0-7%), plagioclase (0-4%) and traces of amphibole and pyroxene. This bentonite is probably the result of the weathering of volcanic ashes. Since there are not many outcrops of this bentonite layer, its spatial distribution is studied by drilling. [less ▲]

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See detailCognitive brain responses during circadian wake-promotion: evidence for sleep- pressure-dependent hypothalamic activations
Reichert, Carolin Franziska; Maire, Micheline; Gabel, Virginie et al

in Scientific Reports (2017), 7(1),

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See detailViolences conjugales : un dilemme pour la justice pénale ? Leçons d’une analyse des enregistrements statistiques effectués dans les parquets belges
Vanneste, Charlotte ULiege

in Champ pénal/Penal field (2017), XIV

Drawing on the analysis of statistics regarding Intimate Partner Violence collected on a large scale at the level of the Belgian prosecutors’ offices, the article reveals a wide gap between the zero ... [more ▼]

Drawing on the analysis of statistics regarding Intimate Partner Violence collected on a large scale at the level of the Belgian prosecutors’ offices, the article reveals a wide gap between the zero tolerance rhetoric conveyed in the normative discourse and actual implementation, which is generally weak and showing divergent judicial practices in the field. Faced with this dilemma, the highly contestable impact of the zero tolerance policy observed in preventing recidivism offers a substantial argument to revisit the role of the criminal justice system in this area. [less ▲]

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See detailViolences conjugales et justice pénale
Glowacz, Fabienne ULiege; Vanneste, Charlotte ULiege

Book published by CNRS Revue.Org (2017)

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See detailRepresentations about physical activity among firefighters. A study in Wallonie
Dubru, Gilles ULiege; Gribomont, Antoine; Cloes, Marc ULiege

Poster (2017, July)

Introduction To be a firefighter is a dangerous job. Many authors have found anxiety, stress, depression, sleep disorders, absenteeism and other deviant behaviors in this type of high-risk occupation ... [more ▼]

Introduction To be a firefighter is a dangerous job. Many authors have found anxiety, stress, depression, sleep disorders, absenteeism and other deviant behaviors in this type of high-risk occupation (Fullerton, Ursano & Wang, 2004 ; Carey, Al-Zaiti, Dean, Sessanna & Finnell, 2011 ; Elliot & Kuehl, 2007). Adopting an active lifestyle is therefore very important in reducing these health risks and thus maximizing the chances of staying healthy. It is for this reason that physical activity has an essential role for these people. According to this determining the place occupied by physical activity within the regional Walloon fire servicesseemed relevant. The first step should be to analyse the firefighters’ representations and lifestyle. Methods An online questionnaire (SurveyMonkey) was developed. It proposed a majority of closed-ended questions facing on age (38 ± 10.4 years), BMI (26.1 ± 3.7), gender (96.7% of men), rank, status (38.3% professional), PA representations and practices, well-being and self-esteem, job satisfaction, … We contacted one of the main firefighters association (FRCSPB) to reach a significant number of topics. 443 questionnaires were collected during a five weeks period. 394 were usable. 376 responses were needed to achieve a 95% confidence level with a 5% confidence interval based on all Belgian Firefighter. Results and discussion Results showed that firefighter showed positive representations about PA and were aware of the benefits of a regular practice on their health. Good stress management and cardiovascular endurance qualities were considerate as important in this profession. Nevertheless, subjects deplored a lack of maintenance of these qualities. The mean BMI of the subjects was above 26, indicating a slight overweight. Sedentary lifestyle, poor infrastructure, injuries due to lack of fitness allow us to suspect an insufficient training. Other factors were pointed out by the subjects (stress, absenteeism, deviant behavior…). Firefighters were generally satisfied with their job and considered that they have an acceptable quality of life. However lack of time, financial and human resources must not be a barrier to the practice of essential PA for those people who are directly related with danger. References Carey, M. G., Al-Zaiti, S. S., Dean, G. E., Sessanna, L., & Finnell, D. S. (2011). Sleep problems, depression, substance use, social bonding, and quality of live in professional firefighters. The international journal of occupational and environmental medicine, 53(8), 928-933. Doi: 10.1097/JOM.0b013e318225898f. Elliot, D. L., & Kuehl, K.S. (2007). The effects of sleep deprivation on firefighters and EMS responders: final report. International Association of fire Chiefs. Fullerton, C. S., Ursano, R.J.,& Wang, L. (2004). Acute stress disorder, posttraumatic stress disorder, and depression in disaster or rescue workers. The American Journal of Psychiatry, 161(8), 1370-76. [less ▲]

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See detailElfriede Jelinek : l'abîme sous nos pieds
Neelsen, Sarah ULiege

Article for general public (2017)

Entretien avec Christian Longchamp sur l’œuvre d'Elfriede Jelinek à l'occasion de la première de l'opéra contemporain "Kein Licht" (mise en scène Nicolas Stehmann , musique Philippe Manoury) à l'Opéra ... [more ▼]

Entretien avec Christian Longchamp sur l’œuvre d'Elfriede Jelinek à l'occasion de la première de l'opéra contemporain "Kein Licht" (mise en scène Nicolas Stehmann , musique Philippe Manoury) à l'Opéra national du Rhin. [less ▲]

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See detailChemical abundances of fast-rotating massive stars. I. Description of the methods and individual results
Cazorla, Constantin ULiege; Morel, Thierry ULiege; Nazé, Yaël ULiege et al

in Astronomy and Astrophysics (2017), 603(A56),

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast- rotating objects with apparently normal surface nitrogen abundances ... [more ▼]

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast- rotating objects with apparently normal surface nitrogen abundances. However, several questions have arisen because of a number of issues, which have rendered a reinvestigation necessary; these issues include the presence of numerous upper limits for the nitrogen abundance, unknown multiplicity status, and a mix of stars with different physical properties, such as their mass and evolutionary state, which are known to control the amount of rotational mixing. Methods: We have carefully selected a large sample of bright, fast-rotating early-type stars of our Galaxy (40 objects with spectral types between B0.5 and O4). Their high-quality, high-resolution optical spectra were then analysed with the stellar atmosphere modelling codes DETAIL/SURFACE or CMFGEN, depending on the temperature of the target. Several internal and external checks were performed to validate our methods; notably, we compared our results with literature data for some well-known objects, studied the effect of gravity darkening, or confronted the results provided by the two codes for stars amenable to both analyses. Furthermore, we studied the radial velocities of the stars to assess their binarity. Results: This first part of our study presents our methods and provides the derived stellar parameters, He, CNO abundances, and the multiplicity status of every star of the sample. It is the first time that He and CNO abundances of such a large number of Galactic massive fast rotators are determined in a homogeneous way. [less ▲]

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See detailPractical Trajectories of Parametric Tools in Small and Medium Architectural Firms
Stals, Adeline ULiege; Elsen, Catherine ULiege; Jancart, Sylvie ULiege

in Future trajectories for computation in design (2017, July)

Initially used as an extension of hand-drawing tools, digital design tools and moreover parametric ones are nowadays deeply modifying the architectural design process. Big offices with star-architects ... [more ▼]

Initially used as an extension of hand-drawing tools, digital design tools and moreover parametric ones are nowadays deeply modifying the architectural design process. Big offices with star-architects were able to adopt these tools but most architects working in a small office are still trying to cope with these parametric design tools. Several questions arise in this regard: what digital tools do architects usually use? Do they express interest for new technologies and software such as parametric ones? What is their understanding of the term “parametric architecture”? Why is this kind of tools still not largely adopted? Going through the results of an online survey, this paper first discusses the meaning of parametric design for architects. The contribution then analyzes the Belgian case regrouping mostly small and medium offices. It reflects particularly on the way architects do or do not implement these new digital tools in their workflows, and it sheds light on the fact that parametric tools also have the potential to free the creativity of SME’s. [less ▲]

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See detailOptimisation of Ship and Offshore Structures and Effective Waterway Infrastructures to Support the Global Economic Growth of a Country/Region
Rigo, Philippe ULiege; Bayatfar, Abbas ULiege; Buldgen, Loïc ULiege et al

in Ship Science & Technology (2017), 11

This paper is the written support of Prof. Ph. Rigo for his keynote lecture at the 5th International Congress for Ship Design and Naval Engineering (March 2017, Columbia). After presenting of the main ... [more ▼]

This paper is the written support of Prof. Ph. Rigo for his keynote lecture at the 5th International Congress for Ship Design and Naval Engineering (March 2017, Columbia). After presenting of the main research activities at ANAST, ULG, he discussed the way to improve the effectiveness of waterway infrastructures to support the global economic growth of a country/region. This paper includes the following parts:  Ship Structure Optimization: methodology to perform ship scantling optimization, decreasing steel weight and keeping the production cost at an acceptable level. We first review the links between “Design” and “Optimization” and secondly define the place of “Ship Structure Optimization” within the general framework of a “Ship Optimization”.  Ship impacts (Collision), with applications to navigation lock and dry dock gates: these gates have to be designed taking into account accidental loads, such as ship collisions. A new simplified analytical method is proposed, based on the so-called super-element method. This method was developed to rapidly assess the crashworthiness of the collided structure and avoid high computational effort of numerical simulations.  Inland waterway Navigation and the development in South America of Inland Waterway Classifications.  EMSHIP, European ERASMUS MUNDUS education program (www.emship.eu): the unique master in Ship & Offshore Structures awarded by the prestigious European Erasmus Mundus Program. Indeed, EMSHIP shares the outstanding experiences of educators, trainers, industrial partners and students in the rapidly developing areas of marine and offshore engineering industry. [less ▲]

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See detailGenetic evaluation of lactation persistency and total milk yield in dairy goats
Siqueira, O. H. G. B. D.; REIS MOTA, Rodrigo ULiege; Oliveira, H. R. et al

in Livestock Research for Rural Development (2017), 29(7),

Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations ... [more ▼]

Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations models such as Wood seem to be appropriate to provide persistency estimates under biological viewpoints. The aim of this study was to fit the Wood lactation model as well as to calculate and evaluate LP as selection criteria in dairy goat breeding programs through genetic parameters estimates. A total of 23,265 first lactation test day milk yield observations from 900 animals were used. The Wood random regression model was primarily fitted to estimate the lactation curve parameters (a, b and c), and then LP and total milk yield (TMY). Posteriorly, a multi-trait animal model was fitted considering simultaneously LP and TMY. The heritability estimates were 0.31 and 0.04 for TMY and LP, respectively. Based on the low LP heritability, selection based only on this trait might be inefficient. In conclusion, the results of this study suggests that selecting for high milk yields might result in high persistency since the genetic correlation between LP and TMY was moderate (0.39). [less ▲]

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