References of "Beckers, Yves"
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See detailIn vitro evaluation of fermentation characteristics of two types of insects, as potential novel protein feeds for pigs
POELAERT, Christine ULg; Beckers, Yves ULg; Despret, Xavier et al

in 13th International Symposium on Digestive Physiology of Pigs (2015, May)

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See detailImproving adjuvant systems for polyclonal egg yolk antibody (IgY) production in laying hens in terms of productivity and animal welfare
Marcq, Christopher ULg; Marlier, Didier ULg; Beckers, Yves ULg

in Veterinary Immunology and Immunopathology (2015), 165(1-2), 54-63

The antibody production in the egg yolks of immunized laying hens is seen as a way of improving animal welfare compared with conventional production by mammals. Immunoglobulin Y (IgY) technology, however ... [more ▼]

The antibody production in the egg yolks of immunized laying hens is seen as a way of improving animal welfare compared with conventional production by mammals. Immunoglobulin Y (IgY) technology, however, has still to address welfare issues linked to the widespread use of an adjuvant in vaccines. Currently, Freund's adjuvants, complete (FCA) or incomplete (FIA), remain the standard. This study sought to evaluate various approaches used to enhance egg yolk antibody production in terms of both productivity and avian welfare. The outer membrane protein (OMP) of Salmonella Typhimurium was used as the prototype antigen. At 20 weeks of age, 56 ISA Brown hens, with specific-Salmonella-free status, were divided into seven groups (n = 8) and received an initial intramuscular immunization. Hens in the two negative control groups received phosphate buffered saline (PBS) or FIA alone. Hens in the other groups received 80 μg of Salmonella OMP emulsified with one of the following adjuvants: 200 μl of FIA alone (T1); 200 μl of FIA supplemented with 8 μg of C-phosphate-guanosine oligodeoxynucleotides (CpG-ODN) (T2); and 280 μl of Montanide ISA 70 VG (T4). Birds in the T3 group received the antigen in emulsion with FIA and were given the tested immunostimulatory component (l-carnitine) via their feed (100 mg/kg). A positive control group (PC) received FCA for the first and final immunizations and FIA for the other boosters. Immunization was repeated after 20, 46, 82 and 221 days. Eggs were collected regularly until 242 days after the first immunization and the anti-Salmonella Typhimurium activities in the yolk were determined by ELISA. After 242 days, the birds were euthanized and the injection sites were evaluated for gross and microscopic lesions. Among the tested immunostimulatory approaches, supplementation of FIA with CpG-ODN led to a significant and long-lasting enhancement of the specific antibody response. This treatment was even higher than the positive benchmark using FCA in the first immunization. The study results showed that a clinical examination of injection sites is insufficient for drawing conclusions about the local tolerance of vaccines. Tissue damage was noticeable in all treatment groups. The birds receiving the Montanide adjuvant, however, had fewer and less severe lesions. Given these limited side-effects, Montanide ISA 70 VG could provide the depot effect needed to ensure the immunomodulatory efficiency of CpG-ODN. The association of these two adjuvants could prove a promising alternative to Freund's adjuvants (FA). [less ▲]

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See detailLes premiers enseignements de l'enquête auprès des élevages laitiers sur leurs évolutions technico-économiques
Beckers, Yves ULg; Vanwindekens, Frédéric ULg; Wyzen, Benoît et al

in Carrefour des Productions animales, 20ème édition "L'exploitation laitière wallonne de demain : du point de vue des acteurs aux propositions de la reccherche" (2015, February 11)

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See detailL'exploitation laitière de demain : conclusions
Beckers, Yves ULg

Conference (2015, February 11)

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See detailL'exploitation laitière de demain : présentation de l'enquête
Beckers, Yves ULg

Conference (2015, February 11)

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See detailChemical characterisation and in vitro assessment of the nutritive value of co-products yield from the corn wet-milling process
Malumba Kamba, Paul ULg; Boudry, Christelle ULg; Roiseux, Olivier et al

in Food Chemistry (2015), 166

The chemical characteristics of co-products recovered during a laboratory-scale wet milling procedure as well as that of whole corn flour were characterised and their digestibility and fermentability ... [more ▼]

The chemical characteristics of co-products recovered during a laboratory-scale wet milling procedure as well as that of whole corn flour were characterised and their digestibility and fermentability value determined using a 2 steps in vitro digestibility and fermentation model of the pig digestive tract. Five co-products differing in their chemical composition were collected and analysed. These co-products differed in their in vitro dry matter Digestibility and in their kinetic of fermentation. High coefficients of digestibility were observed for starchy samples, while low coefficients of digestibility were observed for samples rich in lignocellulosic components. Fermentation patterns of samples analysed were different as well as the profile of volatile fatty acids produced during the fermentation. The production of straight-chain fatty acids produced was significantly correlated with the proportion of starch in the sample, while branched-chain fatty acids were correlated to proteins concentration of samples. [less ▲]

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See detailDes vaches et des prairies : en faut-il encore ?
Beckers, Yves ULg

Conference given outside the academic context (2014)

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See detailUsing milk spectral data for large-scale phenotypes linked to mitigation and efficiency
Soyeurt, Hélène ULg; Vanlierde, Amélie; Vanrobays, Marie-Laure ULg et al

Conference (2014, August 26)

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as ... [more ▼]

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as methane emission (CH4), dry matter intake (DMI) and feed efficiency (FE); however they are available on a small scale. Researches showed that CH4 could be predicted from milk mid-infrared (MIR) spectra, allowing large-scale recording at low cost. The main objective of this study was to show, using a modelling approach, that DMI and FE could be derived from milk MIR spectra. For that, knowledge of body weight (BW) is required; however it was unknown in this study. Derived procedure was based on milk yield and composition, MIR CH4, and modelled standard animal requirements, allowing the prediction of expected BW. An external validation was conducted based on 91 actual records. 95% confidence limit for the difference ranged between -0.66 and 18.84 kg for BW, from -0.02 to 0.26 kg/day for DMI, and from -0.02 to 0.002 kg of fat corrected milk/kg DM for FE. Root mean square errors were 39.66 kg, 0.56 kg/d, and 0.03 kg/DM for the 3 studied traits. P-value for the t-test was not significant for BW and DMI. This suggests the possibility to obtain expected BW and therefore DMI from MIR spectra. Single trait animal test-day models used 1,291,850 records to assess the variability of studied traits. Significant variations were observed for the lactation stage, parity, genetics, and age. These findings were in agreement with the literature except for early lactation. This suggests in conclusion that the MIR information gave similar results for DMI and CH4 for the major part of lactation. The use of this novel method to predict expected BW offers new possibilities interesting for the development of genomic and genetic tools. [less ▲]

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See detailUsing milk spectral data for large-scale phenotypes linked to mitigation and efficiency
Soyeurt, Hélène ULg; Vanlierde, Amélie; Vanrobays, Marie-Laure ULg et al

in Book of abstracts of the 65th annual meeting of the European Federation of Animal Science (2014, August)

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as ... [more ▼]

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as methane emission (CH4), dry matter intake (DMI) and feed efficiency (FE); however they are available on a small scale. Researches showed that CH4 could be predicted from milk mid-infrared (MIR) spectra, allowing large-scale recording at low cost. The main objective of this study was to show, using a modelling approach, that DMI and FE could be derived from milk MIR spectra. For that, knowledge of body weight (BW) is required; however it was unknown in this study. Derived procedure was based on milk yield and composition, MIR CH4, and modelled standard animal requirements, allowing the prediction of expected BW. An external validation was conducted based on 91 actual records. 95% confidence limit for the difference ranged between -0.66 and 18.84 kg for BW, from -0.02 to 0.26 kg/day for DMI, and from -0.02 to 0.002 kg of fat corrected milk/kg DM for FE. Root mean square errors were 39.66 kg, 0.56 kg/d, and 0.03 kg/DM for the 3 studied traits. P-value for the t-test was not significant for BW and DMI. This suggests the possibility to obtain expected BW and therefore DMI from MIR spectra. Single trait animal test-day models used 1,291,850 records to assess the variability of studied traits. Significant variations were observed for the lactation stage, parity, genetics, and age. These findings were in agreement with the literature except for early lactation. This suggests in conclusion that the MIR information gave similar results for DMI and CH4 for the major part of lactation. The use of this novel method to predict expected BW offers new possibilities interesting for the development of genomic and genetic tools. [less ▲]

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See detailComment améliorer les taux de matières utiles dans le lait ? Solutions actuelles et perspectives ...
Beckers, Yves ULg

Conference given outside the academic context (2014)

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See detailLes herbivores, transformateurs de produits fourragers et de coproduits issus de l'agro-industrie en aliments nobles pour l'homme
Decruyenaere, Virginie; Lessire, Françoise ULg; Beckers, Yves ULg et al

in CRA-W (Ed.) La viande bovine remise en question: De sa production à sa consommation (2014, February 19)

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour ... [more ▼]

Les prairies recouvrent près de 50% de la surface agricole utile en Wallonie. Dans certaines régions, la prépondérance des prairies dans le paysage wallon se justifie par des contraintes climatiques. Pour celles-ci bien souvent, les sommes de température et la durée de végétation active sont faibles et limitent considérablement le choix des cultures susceptibles d’atteindre la maturité avant récolte avec certitude. Dans d’autres régions, les prairies s’imposent davantage en raison de contraintes agronomiques : nature du sol, disposition des parcelles, relief du territoire, intérêt dans la rotation pour les prairies temporaires… Ainsi, la grande majorité des prairies de notre Région ne peut pas être remplacée par des cultures ; elles doivent dès lors être perçues comme une bonne alternative à la valorisation du territoire. Grâce à la présence du rumen en amont de l’estomac, les ruminants ont la capacité de transformer des productions non éligibles pour l’homme, tels que les fourrages et les co-produits des industries agro-alimentaires. Ces aliments, de nature essentiellement fibreuse mais pas pour autant pauvres en protéine et en énergie, sont largement fermentés par les micro-organismes du rumen qui les dégradent en composés plus simples, valorisables ensuite par l’animal. Par ce mécanisme, les ruminants contribuent à transformer ces aliments grossiers en produits nobles, tels que le lait et la viande. On comprend dès lors aisément que la présence des ruminants est étroitement liée aux superficies enherbées, elles-mêmes dépendantes des conditions pédo-climatiques d’une région. Malgré des systèmes de production intensifs et l’amélioration continue du potentiel génétique des animaux, les bovins restent peu dépendants des aliments du commerce comparativement aux autres spéculations animales. Ainsi, selon l’APFACA, de l’ordre de 16% des aliments composés produits en Belgique et importés sont utilisés pour les bovins, dont seulement 1/3 est écoulé dans la filière viande bovine. L’herbe, les produits herbagers et les aliments produits sur l’exploitation tels que le maïs restent donc majoritaires dans la ration des bovins élevés pour la production de viande. La valorisation de l’herbe et des produits herbagers dépend fortement des performances zootechniques recherchées. Les objectifs de croissance sont établis, en autre, sur base des prix offerts par la cheville variant avec les catégories d’âge et de poids d’abattage. Ces dernières années, il semble que les animaux abattus un peu plus tardivement soient moins dépréciés qu’auparavant, facilitant la formulation de rations à base de matières premières herbagères. A l’inverse, l’intensification dans le but de produire des animaux abattus plus jeunes ou à un poids supérieur, implique une croissance plus soutenue, et de ce fait la distribution de rations plus denses en énergie. Pour la formulation de telles rations, certains coproduits disposent de valeurs nutritionnelles intéressantes, permettant de satisfaire des besoins nutritionnels élevés, tout en conservant une certaine autonomie alimentaire. Leur valorisation au niveau local représente en outre un intérêt considérable pour la rentabilité des industries agro-alimentaires qui, sans la présence de l’animal, devraient trouver d’autres débouchés pour les coproduits sous peine d’être dans l’obligation de financer leur élimination. Cet exposé a pour objectif d’illustrer les potentiels, mais aussi les limites, des aliments produits localement pour les bovins viande, que ce soit selon leur type (vache de réforme- taurillon…), leur race et leurs performances zootechniques, mais aussi l’intérêt de ces aliments en termes d’efficiences alimentaire et économique. Il analyse les atouts et faiblesses de la spéculation viande bovine en ne se limitant pas à l’échelle de l’animal seul, mais en le replaçant en tant que véritable maillon de la chaîne agro-alimentaire. Ce positionnement permet non seulement de mieux cerner les enjeux de ces élevages au niveau de la production primaire, mais aussi leur importance dans les secteurs amont et aval. [less ▲]

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See detailA côté des produits de la prairie, quels aliments pour complémenter les rations des vaches laitières ?
Beckers, Yves ULg

Conference given outside the academic context (2014)

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See detailL'âge d'abattage influence-t-il la qualité de la viande?
De Maeseneire, Coraline ULg; Sindic, Marianne ULg; Colot, Catherine et al

Article for general public (2014)

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See detailWelke impact heeft de slachtleeftijd bij vleeskuikens op de zintuiglijke eigenschappen van het vlees?
De Maeseneire, Coraline ULg; Sindic, Marianne ULg; Colot, Catherine et al

Article for general public (2014)

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See detailImpact of grazing on carbon dioxide exchanges in an intensively managed Belgian grassland
Jerome, Elisabeth ULg; Beckers, Yves ULg; Bodson, Bernard ULg et al

in Agriculture, Ecosystems & Environment (2014), 194

Given that the soil carbon (C) sequestration potential by grasslands can be used to partly mitigate the total greenhouse gas emissions of livestock production systems, a better understanding of the ... [more ▼]

Given that the soil carbon (C) sequestration potential by grasslands can be used to partly mitigate the total greenhouse gas emissions of livestock production systems, a better understanding of the effects of management practices, and especially grazing, on grassland carbon dioxide (CO2) exchanges has become a major concern. This study aimed at quantifying grazing impact on CO2 fluxes measured by eddy covariance by using innovative data analyses and experiments. For that, we distinguished direct and indirect grazing impact. Indirect impact results from biomass consumption, excretion deposits and soil compaction by cattle that modify CO2 exchanges. Direct impact results from livestock CO2 emissions through respiration that add to total ecosystem respiration. For the indirect impact, the variation during periods with fixed stocking rate of gross primary productivity at light saturation (GPPmax) and normalized dark respiration (Rd,10) was analyzed. On average, GPPmax decreased during grazing periods and increased during non-grazing periods which could be explained by aboveground biomass reduction and re-growth, respectively. In addition, GPPmax variations were negatively correlated to grazing intensity (defined as the product of the stocking rate and the grazing duration). On the contrary, no significant evolution of Rd,10 was found during both grazing and non-grazing periods, probably due to a combination of opposing effects of grazing on the total ecosystem respiration components. The direct impact was emphasized through four specific designed confinement experiments. Each experiment extended over three successive days. On the first and third day, there was no cattle on the plot, while, on the second day, cattle were confined in the main wind direction area of the eddy covariance set-up to increase the stocking rate (≈26livestockunitsha-1). The average livestock CO2 emissions during confinement, FCO2,livestock, were deduced from the differences between half-hourly measurements taken at 24h interval with or without cattle and under similar environmental conditions. They were estimated to be 2.59±0.58kgClivestockunit-1d-1 on average. This result was corroborated by independent estimates based on the C ingested by cattle during confinement. Using an annual average stocking of 2livestockunitsha-1, we found that livestock CO2 emissions represent only 8% of this grassland annual total ecosystem respiration. To our knowledge, this study is the first to quantify both direct and indirect livestock contribution to CO2 fluxes exchanged at the ecosystem scale using the eddy covariance technique. © 2014 Elsevier B.V. [less ▲]

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See detailComparison of three 15N methods to correct for microbial contamination when assessing in situ protein degradability of fresh forages
Kamoun, M.; Ammar, H.; Thewis, André ULg et al

in Journal of Animal Science (2014), 92(11), 5053-5062

The use of stable15N as a marker to determine microbial contamination in nylon bag incubation residues to estimate protein degradability was investigated. Three methods using15N were compared:15N-labeled ... [more ▼]

The use of stable15N as a marker to determine microbial contamination in nylon bag incubation residues to estimate protein degradability was investigated. Three methods using15N were compared:15N-labeled forage (dilution method, LF),15N enrichment of rumen solids-associated bacteria (SAB), and 15N enrichment of rumen liquid-associated bacteria (LAB). Herbage from forages differing in protein and fiber contents (early-cut Italian ryegrass, late-cut Italian ryegrass, and red clover) were freeze-dried and ground and then incubated in situ in the rumen of 3 steers for 3, 6, 12, 24, and 48 h using the nylon bag technique. The15N-labeled forages were obtained by fertilizing the plots where herbage was grown with15NH4 15NO3. Unlabeled forages (obtained from plots fertilized with NH4NO3) were incubated at the same time that (15NH4)2SO4 was continuously infused into the rumen of the steers, and then pellets of labeled SAB and LAB were isolated by differential centrifugation of samples of ruminal contents. The proportion of bacterial N in the incubation residues increased from 0.09 and 0.45 g bacterial N/g total N at 3 h of incubation to 0.37 and 0.85 g bacterial N/g total N at 48 h of incubation for early-cut and late-cut ryegrass, respectively. There were differences (P < 0.001) between uncorrected N degradability values and those corrected for microbial contamination with all of the methods. Apparent N degradability of the low-N, high-fiber forage (latecut ryegrass) was 0.51, whereas the corrected values were 0.85, 0.84, and 0.77 for the LF, SAB, and LAB methods, respectively. With early-cut ryegrass and red clover, the differences between uncorrected and corrected values ranged between 6% and 13%, with small differences among the labeling methods. Generally, methods using labeled forage or labeled SAB and LAB provided similar corrected degradability values. The accuracy in estimating the extent of degradation of protein in the rumen from in situ disappearance curves is improved when values are corrected for microbial contamination of the bag residue. [less ▲]

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See detailPhysicochemical characterization and in vitro assessment of the nutritive value of starch yield from corn dried at different temperatures
Malumba, P.; Odjo, S.; Boudry, Christelle ULg et al

in Stärke = Starch (2014), 66

To assess modifications induced in starch granules during high temperature drying of corn grain and their effect on the nutritive value of corn-starch, physicochemical and structural characteristics of ... [more ▼]

To assess modifications induced in starch granules during high temperature drying of corn grain and their effect on the nutritive value of corn-starch, physicochemical and structural characteristics of starch granules from corn grains dried at different temperatures have been determined. Additionally, their in vitro digestibility and fermentation patterns were investigated, using a two steps in vitro model of the pig digestive tract. High drying temperatures induced a partial gelatinization of starch granules and produced a very favorable substrate for porcine pancreatic amylase and led to an altered physical structure which affected the rate and extent of starch granules digestion by gastric and pancreatic enzymes. Starch micrographs showed that granules extracted from corn dried at 130°C were less angular, bigger, and had smoother surface than granules extracted from corn dried at lower temperature. High-temperature drying increased the digestibility of wet-milled starch granules, while the residues of starch from corn dried at lower temperature produced higher volume of gas during their in vitro fermentation, despite their more pronounced crystalline characteristic. The residues from pepsin–pancreatic digestion of overall samples analyzed showed highly degraded and pitted granules or fragmented external shells, starch from corn dried at 130°C being the most degraded. Aforementioned changes of nutritional attributes of starch granules are discussed according to the restructuration occurring within both their amorphous and crystalline phase, as well as to the changes of the granules size and purity. [less ▲]

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See detailChemical and biological evaluation of the nutritive value of Algerian green seaweed Ulva lactuca using in vitro gas production technique fior ruminant animals
Zitouni, Hind; Arhab, Rabah; Boudry, Christelle ULg et al

in International Journal of Advanced Research (2014), 2(4), 916-925

This study aimed to determine the nutritive value of seaweed Ulva lactuca collected from the Algerian coast by estimation of its chemical composition and fermentation characteristics, comparatively to ... [more ▼]

This study aimed to determine the nutritive value of seaweed Ulva lactuca collected from the Algerian coast by estimation of its chemical composition and fermentation characteristics, comparatively to vetch-oat hay (control), using in vitro gas production technique. Seaweed and control were incubated with rumen liquor taken from fistulated and non lactating cows. Gas production was recorded at: 2, 4, 6, 8, 12, 24, 48 and 72h. The in vitro rumen fermentation parameters were measured after 24h and 72h of fermentation. Proteins degradability was investigated by the enzymatic technique using a protease extracted from Streptomyces griseus. The results showed a wide variation between the chemical components of seaweed and conventional fodder used as control. The main constituents in Ulva lactuca were ashes (39.1% DM), fibers (22.8 % DM) and proteins (15.3% DM). The gas production profile of seaweed during 72h of incubation showed a slow and low gas production. Cumulative gas production obtained after 24h for seaweed (42 ml/g OM) was significantly lower than control (128.4 ml/g OM) (P<0.001). pH, ammonia, volatile fatty acids (VFAs), apparent digestibility of dry matter (DDM), organic matter digestibility (OMD) and metabolizable energy (ME) were significantly different between seaweed and vetch-oat hay (6.86, 290.1 mg/ml, 1.25 mmol/g DM, 38.3%, 29.2%, 3.81MJ/Kg DM respectively for seaweed). Protein degradability measurement indicates the weak hydrolysis of seaweed crude protein which is beneficial for ruminants. This study showed that the use of Ulva lactuca as non conventional feed in ruminant nutrition can be considered under certain conditions. [less ▲]

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