References of "Dufrasne, Isabelle"
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See detailSystematic Review and Meta-Analysis: Identification of Factors Influencing Milking Frequency of Cows in Automatic Milking Systems Combined with Grazing.
Lessire, Françoise ULiege; Moula, Nassim ULiege; Hornick, Jean-Luc ULiege et al

in Animals (2020), 10(5), 913

More dairy farms (up to more than one in four in some countries) are equipped with automatic milking systems (AMS) worldwide. Because of the positive impacts of grazing, e.g., on animal welfare or on ... [more ▼]

More dairy farms (up to more than one in four in some countries) are equipped with automatic milking systems (AMS) worldwide. Because of the positive impacts of grazing, e.g., on animal welfare or on production costs, numerous researchers have published papers on the combination of AMS with grazing. However, pasture-based AMS usually causes a reduction in milking frequency (MF) compared to indoors systems. The objectives of this meta-analysis were to review publications on the impacts of pasture-based AMS on MF and mitigation strategies. First, data from 43 selected studies were gathered in a dataset including 14 parameters, and on which a Principal Component Analysis (PCA) was performed, leading to the description of four clusters summarizing different management practices. Multiple pairwise comparisons were performed to determine the relationship between the highlighted parameters of MF on milk yield (MY). From these different analyses, the relationship between MF and MY was confirmed, the systems, i.e., Clusters 1 and 2, that experienced the lowest MF also demonstrated the lowest MY/cow per day. In these clusters, grazed grass was an essential component of the cow’s diet and low feeding costs compensated MY reduction. The management options described in Clusters 3 and 4 allowed maintenance of MF and MY by complementing the cows’ diets with concentrates or partial mixed ration supplied at the AMS feeding bin or provided at barn. The chosen management options were closely linked to the geographical origin of the papers indicating that other factors (e.g., climatic conditions or available grasslands) could be decisional key points for AMS management strategies. [less ▲]

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See detailManaging the high variability of compressed sward heights to model grass growth on pastures using satellite images
Nickmilder, Charles ULiege; Soyeurt, Hélène ULiege; Dufrasne, Isabelle ULiege et al

Poster (2020, January 31)

ROADSTEP is a Walloon research program aiming to develop decision tools to help farmers in their daily herd monitoring on pastures. One of the aims is to develop a modelling tool to predict the ... [more ▼]

ROADSTEP is a Walloon research program aiming to develop decision tools to help farmers in their daily herd monitoring on pastures. One of the aims is to develop a modelling tool to predict the availability of pasture feeding based on satellite images, meteorological variables and soil characteristics. So, 72,975 compressed sward heights (CSH) have been measured on 30 parcels located in 3 farms using Jenquip EC20G platemeter in 2018 and 2019. CSH records (175 ± 53 mm) seemed to be normally distributed based on the low values of skewness (-1.96) and kurtosis (3.28). However, CSH gathered per parcel and per date showed a trend to unfit a normal distribution and seemed to be dependent on the location of the measurement spot on the parcel. Indeed, the observed kurtosis per parcel and test date were comprised between 0.64 and 27.40. Skewness values ranged from -4.39 to -1.38. These high kurtosis values highlight that CSH records were not normally distributed per parcel. Therefore, the current way to use an average CSH to represent a parcel is not the best choice as this value is not representative. This implies the need to adopt an unbiased approach that enables the comparison of CSH and other variables between dates. The chosen method consists in splitting the parcels in square sub-blocks. Each cell of this grid gathers all the climatic-soil related-satellite-median CSH data and is used as the unitary entity to train the predictive model of the biomass available in the pasture. [less ▲]

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See detailGlobal AMS R&D Online Showcase: Belgium
Lessire, Françoise ULiege; Dufrasne, Isabelle ULiege

Conference (2019, December 10)

Présentation faisant le point des avancées du robot de traite en Belgique et en particulier en combinaison avec le pâturage

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See detailContribution of milk mid-infrared spectrum to improve the accuracy of test-day body weight predicted from stage, lactation number, month of test and milk yield
Soyeurt, Hélène ULiege; Froidmont, Éric; Dufrasne, Isabelle ULiege et al

in Livestock Science (2019), 227(2019), 82-89

A regular and repeated recording of body weight (BW) is useful information for herd management. BW can bepredicted regularly from animal characteristics such as age, lactation number, or lactation stage ... [more ▼]

A regular and repeated recording of body weight (BW) is useful information for herd management. BW can bepredicted regularly from animal characteristics such as age, lactation number, or lactation stage. Those traits areunfortunately animal unspecific. Adding animal specific information, which can be easily obtained on a largescale, to the BW prediction would be of utmost importance. There are good scientific reasons to suspect linksbetween BW and animal specific characteristics, available in a repeated fashion, such as milk yield and milkcomposition. This study aimed to demonstrate the feasibility of predicting test-day BW from stage, lactationnumber, month of test, milk yield and mid-infrared spectra, representing milk composition. Five models weretested initially from 721 BW records collected in 6 herds: day in milk + number of lactation (equation 1a);equation1a + milk yield (equation 1b); only spectral data (equation 1c); equation 1c + equation 1a (equation2); equation 2 + milk yield (equation 3). Then 3 other equations included the same explicative variables, exceptthat the spectral data were regressed using second order Legendre Polynomials (PL) to take into account changesof spectral data within lactation. Equation 1a and 1b were built using linear regressions and equation 1c until 3were built using partial least square regressions. These 3 last equations had a higher number of factors. Adding ofMIR data in the equation increased of 7% the values of cross-validation R² (R²cv). Potential BW outliers werediscarded using a residual analysis based on equation 3. From 662 records, the following statistical parameterswere obtained: the calibration coefficient of determination (R²c) = 0.65, R²cv = 0.61, calibration root meansquared error of prediction (RMSEP)=38 kg, and RMSEPcv=40 kg. Low variation of R²c and RMSEPc valuesobtained from the herd validation confirmed the herd independence of predictions. However, large variabilitywas observed for RMSEPv (37 to 64 kg) suggesting the need to increase the dataset in order to improve therobustness of the equation. By applying the equations on a large spectral database, it was confirmed that theaddition of MIR data allows to better model the BW evolution within lactation. Based on these preliminaryresults, and if a larger validation confirms thesefindings, this approach could be used to develop equations thatare better able to assess BW throughout lactation(s), BW being an important element for management andselection tools. [less ▲]

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See detailComparison of three gradients of grazed grass in dairy cows diet in terms of environmental and zootechnical performances
Lessire, Françoise ULiege; Dufrasne, Isabelle ULiege

in O'Brien, Bernadette; Henessy, Deirdre; Shalloo, Laurence (Eds.) et al Precision Livestock Farming'19 (2019, August 26)

Climatic change induces challenges in grazing management, which could tempt farmers to keep their cows indoors. To assess the environmental and economic impact of diets with different percentages of ... [more ▼]

Climatic change induces challenges in grazing management, which could tempt farmers to keep their cows indoors. To assess the environmental and economic impact of diets with different percentages of grazed grass, thirty-three Holstein cows in early lactation were divided into three groups from 27 April to 7 July 2018. These groups were allocated an increasing proportion of grazed grass in their diet. No access to grazed grass was possible for Group 1 (0%), while Group 2 and 3 were granted access to pasture 21w. Group 2’s (100%) diet was composed of 100% grass. Group 3 (50%) received silage in the barn as well as grazed grass. The access to pasture was adapted to achieve a proportion of 50% grass in the diet. Sward height was measured every week with an electronic rising plate meter (EC 20®), and the nutritional composition of grazed grass was evaluated. All the groups’ diet was complemented with concentrates delivered by the automatic concentrate supplier, where the Guardian® was located in order to measure the methane emitted at each visit. Methane emissions were also assessed by predictions based on the mid infra-red (MIR) spectrum of milk samples. Animal performance was recorded and the milk carbon footprint was estimated by the Feedprint®. No difference in milk yield between the groups was recorded. Predictions based on the MIR spectra analysis showed a slight decrease in methane emission per cow and per day in the 100% group, but this decrease was not confirmed by the breath samples measurements. The feeding costs were in favour of the 100% group. The carbon-footprint of the milk produced with 100% or 50% of grazed grass was lower than for the zero-grazing cows. [less ▲]

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See detailDetermination of enteric methane emissions of dairy cows fed with different diets and relationship with milk yield and ruminal function in order to improve advice for farmers
Lessire, Françoise ULiege; Dufrasne, Isabelle ULiege

in O'Brien, Bernadette; Henessy, Deirdre; Shalloo, Laurence (Eds.) et al Precision Livestock Farming'19 (2019, August 26)

Methane from ruminal fermentation, termed enteric methane, contributes 40% of the total agricultural emissions (Gerber et al., 2014). Mitigation of methane production could allow for a reduction in the ... [more ▼]

Methane from ruminal fermentation, termed enteric methane, contributes 40% of the total agricultural emissions (Gerber et al., 2014). Mitigation of methane production could allow for a reduction in the impact of livestock on climate change and may improve the public perception towards this sector. Milk yield, methane emissions, carbon footprint and dietary costs were measured in experimental and commercial farms in different diet conditions: enriched fat diet (linseed or canola), high concentrate diet, high level of starch in diet or grazing. Individual milk samples were analysed monthly for milk quality and for methane emissions predicted by milk spectra analysis. The first results showed that methane emissions per kg of milk can vary from 11 to 20 g. Preliminary comparison between the diets demonstrated that feeding with grazed grass was beneficial in terms of feeding costs and environmental impact while methane emissions per kg milk were higher. Diets with low fibre content can have a beneficial impact to decrease methane emissions but could disturb ruminal function. These results will allow us to predict methane emissions and environmental impacts of milk production according to the diet composition, dietary costs, lactation stage and milk production. From these results, advice about feeding strategies could be given to reach the best compromise between environmental and economic objectives. [less ▲]

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See detailValidation of the prediction of body weight from dairy cow characteristics and milk MIR spectra
Soyeurt, Hélène ULiege; Froidmont, E.; Dufrasne, Isabelle ULiege et al

in Book of Abstracts of the 70th Annual Meeting of the European Association for Animal Production (2019, August)

Body weight (BW) recording is of interest to optimize herd management and environmental fingerprint. Due to its cost, a weighing system is not installed in many farms. Linear type traits are mostly ... [more ▼]

Body weight (BW) recording is of interest to optimize herd management and environmental fingerprint. Due to its cost, a weighing system is not installed in many farms. Linear type traits are mostly available only once in the lifetime of the cow. So, an interest exists to develop a method to predict routinely BW with traits easily recorded and cheap. First investigation was conducted one year ago to build a prediction equation of BW from parity, test month, milk yield, days in milk and milk MIR spectrum. This study based on 717 records obtained a herd validation root mean square error (RMSEv) ranged from 37 to 64 kg. Cross-validation (cv) R2 was equal to 0.51 with RMSE of 50 kg. This equation was applied on 1,161 milk MIR spectra collected in the GplusE project from Holstein cows. Validation R2 was 0.51 with RMSEv of 65 kg. A total of 109 spectra had a global H distance higher than 3 suggesting spectral outliers. After their removal, R2v increased slightly (0.54). Difference of RMSEv can be explained by a lack of spectral variability in the calibration set. So, the 2 datasets were merged to build a PLS regression including the same predictive traits as the first study. After a spectral cleaning based on GH and residual analysis, the best equation used 1,837 records and gave a 10 fold R2cv of 0.64±0.02 with a RMSEv of 46±2 kg. The ability to predict BW was improved by adding this new data. Lowest errors were observed for BW ranged from 500 to 750 kg which represents 94% of the set. So, low and high BW lack in the calibration set. This study confirms the preliminary results and the potentiality to predict an indicator of body weight. This alternative BW prediction could explain a part of the BW variability not already covered by other BW predictors as those based on linear scores. Moreover, this method allows to consider the past information if the spectral data is available. This approach should help research on BW changes and selection for this trait in the future. [less ▲]

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See detailPrediction of test-day body weight from dairy cow characteristics and milk spectra
Soyeurt, Hélène ULiege; Colinet, Frédéric ULiege; Froidmont, E. et al

in Book of Abstracts of the 69th Annual Meeting of the European Federation of Animal Science (2018, August)

The knowledge of individual body weight (BW) is a management key in terms of feed efficiency and to assess the environmental footprint of dairy production. From 6 farms, BW were measured on 735 Holstein ... [more ▼]

The knowledge of individual body weight (BW) is a management key in terms of feed efficiency and to assess the environmental footprint of dairy production. From 6 farms, BW were measured on 735 Holstein cows. Daily milk samples were collected on these weighed cows and analysed by mid-infrared spectrometry. The stage and number of lactation were also collated. A spectral cleaning was conducted by calculating GH distances from 17 principal components. Spectra with a GH greater than 3 were discarded. The final dataset contained 720 records. Predicting equations were based on Partial Least Squares regressions. Cross-validation coefficient of determination (R2cv) and root mean square error (RMSEPcv) of the equation including only spectral data were of 0.19 and 65 kg. Then, days in milk, month of test and lactation stage were added. The obtained R2cv and RMSEPcv increased (0.43 and 54 kg). The part of the information derived from the spectral data was equal to 6%. By adding the daily milk yield, the BW prediction was slightly improved and showed a R2cv of 0.45 and a RMSEPcv of 53 kg. The use of Legendre Polynomials to regress the spectral data following the day in milk did not improve the predictability. By deleting samples showing a squared residual higher than its mean + 3 times of its standard deviation, the final equation included 668 samples (93% of the initial set) and had a R2cv of 0.58 and RMSEPcv of 42 kg. A herd cross-validation was then performed to assess the robustness of the developed equation. RMSEPv ranged from 40 to 58 kg. This preliminary study showed the potentiality to predict an indicator of body weight. As this prediction uses easy to record explicative variables and if a larger validation confirmed the obtained results, this prediction equation could be used to develop large scale study about feed efficiency. Moreover, this method allows to consider the past information if spectral data are available. [less ▲]

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See detailMethane emissions and milk carbon footprint of dairy cows at grazing or fed with a concentrate diet
Lessire, Françoise ULiege; Scohier, Catherine; Dufrasne, Isabelle ULiege

in Sustainable meat and milk production from grassalnds (2018, June 17)

In order to compare methane emissions and carbon footprint of milk produced by dairy cows with different feeding strategies, a trial was carried out on 2 groups of 11 Holstein cows from May to July 2017 ... [more ▼]

In order to compare methane emissions and carbon footprint of milk produced by dairy cows with different feeding strategies, a trial was carried out on 2 groups of 11 Holstein cows from May to July 2017. One group was grazing day and night with a target sward availability of 17 kg per cow. The other one received a diet composed of dried pellets mixed with straw, molasses and alfalfa hay. In the barn where all the cows had permanent access, an automatic concentrate supplier provided concentrates to complement the ration of both groups. Methane emissions were assessed by predictions based on the mid infra-red spectra of milk samples and by the Guardian® located in the automatic concentrate supplier. Furthermore, ruminal fluid was sampled monthly on 5 cows of each group to check the ruminal function (pH, redox potential, presence and mobility of protozoa). The aim of this study was to get a holistic overview of the effect of contrasted feeding practices on methane emissions, environmental impact, zootechnical and economical performances. Grazing decreased feeding costs and feeding environmental impacts while methane emissions per kg milk increased. This highlights the complexity of mitigation actions of GHG in the dairy sector. [less ▲]

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See detailGrazing practices in three European countries: results of a survey in dairy farms
Lessire, Françoise ULiege; Scohier, Catherine; Kristensen, Troels et al

in Sustainable meat and milk production from grassalnds (2018, June 17)

Grassland plays an important role in mitigation of greenhouse gases (GHG) emissions from the agricultural sector by sinking carbon (Soussana et al., 2010). Thus grazing is often essential for maintenance ... [more ▼]

Grassland plays an important role in mitigation of greenhouse gases (GHG) emissions from the agricultural sector by sinking carbon (Soussana et al., 2010). Thus grazing is often essential for maintenance of grassland. Furthermore grazing has demonstrated positive effects on animal welfare, production costs, landscape and biodiversity. However grazing is decreasing in most European countries. For the project Life Dairyclim, a survey was led in the three partner countries for a better understanding of grazing practices and of perceptions and expectations of dairy farmers. A questionnaire was thus sent in dairy farms of South-Belgium (BE), Luxembourg (LU) and Denmark (DK). From 1439 filled forms, 1147 declared that lactating cows grazed (80%) but this result reflects different situations: 95% LC were grazing in BE while this percentage dropped to 83% in LU and 37% in DK. This lower % of LC seemed to be linked to larger farm surface, bigger herd size and increased milk yield. The opinion about benefits of grazing depended on the grazing practices. Grazing farmers were very convinced about beneficial effects of grazing on animal welfare (95.4%) and on landscape preservation (86.1%). Surprisingly the positive effect on environment was mentioned in only 61.3% forms and even a negative impact was cited in 16.6%. Eighty six % of surveyed farmers expected to continue grazing. [less ▲]

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See detailCombiner robot de traite et pâturage
Lessire, Françoise ULiege; Dufrasne, Isabelle ULiege

Article for general public (2017)

La traite robotisée s'impose de plus en plus dans les exploitations laitières avec pour corollaire la diminution du pâturage. Pourtant cette pratique est bénéfique au niveau économique et environnemental ... [more ▼]

La traite robotisée s'impose de plus en plus dans les exploitations laitières avec pour corollaire la diminution du pâturage. Pourtant cette pratique est bénéfique au niveau économique et environnemental ainsi que du point de vue du bien-être animal. Mais est-ce possible de concilier robot de traite et pâturage? C'est la question à laquelle le projet Européen Autograssmilk a tenté de répondre. [less ▲]

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See detailImpact of grazing practices on farm self-sufficiency, milk and economic performances of three automatized farms
Lessire, Françoise ULiege; Scohier, Catherine ULiege; Dufrasne, Isabelle ULiege

in Porqueddu, Claudio; Franca, Antonello; Lombardi, Giampiero (Eds.) et al Grassland resources for extensive farming systems in marginal lands: major drivers and future scenarios (2017, May 07)

The dairy sector is facing serious economic difficulties linked to low milk price and volatility of feedstuff price. In this context, reducing farm inputs is necessary. Optimization of use of grazed ... [more ▼]

The dairy sector is facing serious economic difficulties linked to low milk price and volatility of feedstuff price. In this context, reducing farm inputs is necessary. Optimization of use of grazed, ensiled or dried grass could be a key strategy to improve self-sufficiency and thus to decrease feeding costs. Yet, practice of grazing is disappearing due to several factors, including increased size of dairy herds and development of automation. However combining grazing and automatic milking systems (AMS) is possible. Three Walloon dairy farms equipped with an AMS were monitored to assess their grazing practices, grass proportion in the cows’ diet both at barn and on pasture and the economic advantages linked to grass use in 2015. These farms practiced various grazing strategies including full-grass system (FG), day and night grass allocation (DNG), and rotational grazing (RG) completed with a partial mixed ration. The effects of grazing on milk yield (MY) were also evaluated. Grazing reduced the daily feeding costs per cow in all systems with variable impact due to grazing management. The most pronounced decline was observed in FG with a severe drop in MY. Conversely, the decrease in MY was less marked in the other farms. [less ▲]

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See detailThe effect of concentrate allocation on traffic and milk production of pasture based cows milked by an automatic milking system
Lessire, Françoise ULiege; Froidmont, Eric; Shortall, John et al

in Animal (2017), 11(4), 1-9

Increased economic, societal and environmental challenges facing agriculture are leading to a greater focus on effective way to combine grazing and automatic milking systems (AMS). One of the fundamental ... [more ▼]

Increased economic, societal and environmental challenges facing agriculture are leading to a greater focus on effective way to combine grazing and automatic milking systems (AMS). One of the fundamental aspects of robotic milking is cows’ traffic to the AMS. Numerous studies have identified feed provided, either as fresh grass or concentrate supplement, as the main incentive for cows to return to the robot. The aim of this study was to determine the effect of concentrate allocation on voluntary cow traffic from pasture to the robot during the grazing period, to highlight the interactions between grazed pasture and concentrate allocation in terms of substitution rate and the subsequent effect on average milk yield and composition. Thus, 29 grazing cows, milked by a mobile robot, were monitored for the grazing period (4 months). They were assigned to 2 groups: a low concentrate (LC) group (15 cows) and a high concentrate (HC) group (14 cows) receiving 2 kg and 4 kg concentrate per cow per day respectively. Two allocations per day of fresh pasture were provided at 0700h and 1600h. The cows had to go through the AMS to receive the fresh pasture allocation. The effect of concentrate level on robot visitation was calculated by summing milkings, refusals and failed milkings/cow per day. The impact on average daily milk yield and composition was also determined. The interaction between lactation number and month was used as an indicator of pasture availability. Concentrate allocation increased significantly robot visitations in HC (3.60 ± 0.07 visitations/cow per day in HC - 3.10 ± 0.07 visitations/cow per day in LC; P<0.001) while milkings/cow per day were similar in both groups (LC: 2.37 ± 0.02/day - HC: 2.39 ± 0.02/day; ns). The average daily milk yield over the grazing period was enhanced in HC (22.39 ± 0.22 kg/cow per day in HC- 21.33 ± 0.22 kg/cow per day in LC; P<0.001). However the gain in milk due to higher concentrate supply was limited with regards to the amount of provided concentrates. Milking frequency in HC primiparous compared with LC was increased. In the context of this study, considering high concentrate levels as an incentive for robot visitation might be questioned, as it had no impact on milking frequency and limited impact on average milk yield and composition. By contrast, increased concentrate supply could be targeted specifically to primiparous cows. [less ▲]

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See detailEnquête sur les pratiques de pâturage en Wallonie: Résultats et conclusions
Lessire, Françoise ULiege; Dufrasne, Isabelle ULiege

Conference given outside the academic context (2017)

The role of grasslands as a C sink is generally accepted. It is considered that permanent grasslands allow annual C storage rates between 22 and 44 g C/m2/y (Soussana et al., 2010) thereby contributing to ... [more ▼]

The role of grasslands as a C sink is generally accepted. It is considered that permanent grasslands allow annual C storage rates between 22 and 44 g C/m2/y (Soussana et al., 2010) thereby contributing to the mitigation of greenhouse gas (GHG) emissions. Grassland preservation has several other advantages including a decrease in feeding costs (Dillon et al., 2005), a positive effect on cows’ health (e.g.a decrease in lameness) (Burow et al., 2011) and the provision of a positive image to consumers. Despite these arguments, grazing is decreasing in Europe and grasslands are disappearing. A better understanding of grazing practices and of farmers’ expectations could suggest ways of improving these practices and limiting grassland disappearance. As a result, Walloon dairy farmers were surveyed in December 2015 and the preliminary results are presented below. [less ▲]

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See detailPâturer avec un robot de traite: une diversité de stratégies...
Brocard, Valérie; Lessire, Françoise ULiege; Cloet, Estelle et al

in Fourrages (2017), 229

Au cours du projet Autograssmilk, différentes stratégies ont été testées pour maximiser la production de lait ( et réduire les coûts alimentaires) en combinant robot et pâturage dans une large gamme de ... [more ▼]

Au cours du projet Autograssmilk, différentes stratégies ont été testées pour maximiser la production de lait ( et réduire les coûts alimentaires) en combinant robot et pâturage dans une large gamme de contextes: des systèmes pâturants à faibles coûts alimentaires, jusqu'à des systèmes plus intensifs tournés vers la recherche de productivité animale. Ainsi, les points-clés de la réussite d'un système combinant robot de traite et pâturage ont pu être décrits, notamment pour le choix d'un mode de gestion de l'alimentation (et son adaptation aux variations d'herbe disponible), la circulation des vaches (selon le nombre de vaches traites par robot), la distance des parcelles (possibilité d'utiliser un robot déplaçable). Les animaux ont la faculté de s'habituer à un nouveau mode de fonctionnement. [less ▲]

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See detailTraite robotisée, grands troupeaux et pâturage: retour d'expérience de 2 exploitations en Belgique
Lessire, Françoise ULiege; Knoden, David; Dufrasne, Isabelle ULiege

in Fourrages (2017), 229

La technique de traite robotisée entraîne dans bon nombre de cas l’abandon du pâturage ou, du moins, une forte diminution de la part d’herbe pâturée dans la ration des vaches laitières. Cet article montre ... [more ▼]

La technique de traite robotisée entraîne dans bon nombre de cas l’abandon du pâturage ou, du moins, une forte diminution de la part d’herbe pâturée dans la ration des vaches laitières. Cet article montre qu’il est possible de concilier traite robotisée, pâturage et grands troupeaux tout en gardant de bonnes performances économiques. [less ▲]

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See detailEvaluation of the ruminal function of Belgian dairy cows suspected of subacute ruminal acidosis.
Lessire, Françoise ULiege; Knapp, Emilie; Theron, Léonard et al

in Vlaams Diergeneeskundig Tijdschrift (2017), 86(1), 16-23

Subacute ruminal acidosis (SARA) has been considered a major pathology in high producing dairy herds for years. These findings were corroborated by several studies in Europe. However, different feeding ... [more ▼]

Subacute ruminal acidosis (SARA) has been considered a major pathology in high producing dairy herds for years. These findings were corroborated by several studies in Europe. However, different feeding practices and herds’ production levels are found in Southern Belgium. This study aimed to ascertain whether dairy cows of several herds from the south of Belgium (Wallonia) with a suspicion of SARA really did present too low ruminal pH values. Twenty-four herds were visited and 172 cows were sampled using an oropharyngeal device to collect ruminal fluid, i.e. Geishauser probe. On the samples, three tests were performed: pH measurement, methylene blue reduction test and microscopic evaluation of protozoa vitality. Based on these analyses, no cows demonstrated pH values lower than 5.5 and, only ten cows could be considered at risk for SARA. By contrast, in eightteen cows, pH values higher than 7.0 were measured and ruminal inactivity was suspected. In this study, ruminal alkalosis appeared to be more frequently observed than SARA. [less ▲]

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See detailDevelopment of an open-source algorithm based on inertial measurement units (IMU) of a smartphone to detect cattle grass intake and ruminating behaviors
Andriamandroso, Andriamasinoro ULiege; Lebeau, Frédéric ULiege; Beckers, Yves ULiege et al

in Computers and Electronics in Agriculture (2017), 139

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a ... [more ▼]

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a smartphone, which contains an accelerometer, a gyroscope, a magnetometer and location sensors signals sampled at 100 Hz. This equipment was mounted on 19 grazing cows of different breeds and daily video sequences were recorded on pasture of different forage allowances. After visually analyzing the cows’ movements on a calibration database, signal combinations were selected and thresholds were determined based on 1-s time windows, since increasing the time window did not increase the accuracy of detection. The final algorithm uses the average value and standard deviation of two signals in a two-step discrimination tree: the gravitational acceleration on x-axis (Gx) expressing the cows’ head movements and the rotation rate on the same x-axis (Rx) expressing jaw movements. Threshold values encompassing 95% of the normalized calibrated data gave the best results. Validation on an independent database resulted in an average detection accuracy of 92% with a better detection for rumination (95%) than for grass intake (91%). The detection algorithm also allows for characterization of the diurnal feeding activities of cattle at pasture. Any user can make further improvements, for data collected at the same way as the iPhone’s IMU has done, since the algorithm codes are open and provided as supplementary data. [less ▲]

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See detailChallenges and priorities for modelling livestock health and pathogens in the context of climate change
Özkan, Şeyda; Vitali, Andrea; Lacetera, Nicola et al

in Environmental Research (2016), 151(Supplement C), 130-144

Climate change has the potential to impair livestock health, with consequences for animal welfare, productivity, greenhouse gas emissions, and human livelihoods and health. Modelling has an important role ... [more ▼]

Climate change has the potential to impair livestock health, with consequences for animal welfare, productivity, greenhouse gas emissions, and human livelihoods and health. Modelling has an important role in assessing the impacts of climate change on livestock systems and the efficacy of potential adaptation strategies, to support decision making for more efficient, resilient and sustainable production. However, a coherent set of challenges and research priorities for modelling livestock health and pathogens under climate change has not previously been available. To identify such challenges and priorities, researchers from across Europe were engaged in a horizon-scanning study, involving workshop and questionnaire based exercises and focussed literature reviews. Eighteen key challenges were identified and grouped into six categories based on subject-specific and capacity building requirements. Across a number of challenges, the need for inventories relating model types to different applications (e.g. the pathogen species, region, scale of focus and purpose to which they can be applied) was identified, in order to identify gaps in capability in relation to the impacts of climate change on animal health. The need for collaboration and learning across disciplines was highlighted in several challenges, e.g. to better understand and model complex ecological interactions between pathogens, vectors, wildlife hosts and livestock in the context of climate change. Collaboration between socio-economic and biophysical disciplines was seen as important for better engagement with stakeholders and for improved modelling of the costs and benefits of poor livestock health. The need for more comprehensive validation of empirical relationships, for harmonising terminology and measurements, and for building capacity for under-researched nations, systems and health problems indicated the importance of joined up approaches across nations. The challenges and priorities identified can help focus the development of modelling capacity and future research structures in this vital field. Well-funded networks capable of managing the long-term development of shared resources are required in order to create a cohesive modelling community equipped to tackle the complex challenges of climate change. [less ▲]

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