Sébastien Couvreur | Ecole Supérieure d'Agriculture d'Angers (original) (raw)

Papers by Sébastien Couvreur

International audienceIn 2011, the French government initiated an ambitious experiment dedicated ... more International audienceIn 2011, the French government initiated an ambitious experiment dedicated to pedagogical innovations through the funding of 37 projects experimenting creative, collective, and cross-disciplinary approaches for innovative teaching. One of these projects, MAN-IMAL, was the first France-based international higher education degree programme exclusively based on the "One World, One Health" initiative. MAN-IMAL experimented: i) the use of ICTE; ii) a multidisciplinary approach developed by academics from Agricultural, Medical, and Veterinary Sciences; iii) as well as the interest of mixing students from various backgrounds (medical and veterinary studies, agricultural engineering, biological, and pharmacy studies). The developed training courses included several Bachelor-level modules and an international One Health post-graduate degree entirely taught in English, the latter experimenting a multicultural approach. The teachers involved in the MAN-IMAL prog...

International audienceLa transition agroécologique initiée depuis les années 1990 vise à développ... more International audienceLa transition agroécologique initiée depuis les années 1990 vise à développer de nouveaux systèmes d'élevage qui optimisent la productivité tout en améliorant la santé des animaux et en diminuant les impacts environnementaux. Dans le cas particulier de l'élevage de bovins laitiers, la valorisation des prairies par le pâturage devrait permettre de répondre à plusieurs piliers de l'agroéocologie. Cette pratique est néanmoins complexe à mettre en oeuvre et une gestion inadaptée peut compromettre les bénéfices attendus (valorisation de l'herbe non optimale, stress des animaux sur les prairies, etc.). Dans le cadre de l'élevage de précision, des outils se développent pour améliorer les performances des exploitations mais ceux à destination du pâturage restent marginaux et de plus-value discutable. A ce propos, le comportement et la position des vaches laitières devraient servir de support au développement de nouveaux outils puisqu'ils sont de...

Computers and Electronics in Agriculture, 2022

L’objectif de ce travail a ete d’evaluer le lien entre le type de vaches de reforme de l’AOP Main... more L’objectif de ce travail a ete d’evaluer le lien entre le type de vaches de reforme de l’AOP Maine Anjou, les pratiques de finition et la qualite de la viande. Pour cela, les muscles Longissimus Thoracis (LT) et Rectus Abdominis (RA) de 111 vaches de reforme de race Rouge des Pres ont ete preleves et caracterises physico- chimiquement et sensoriellement (RA uniquement). Les pratiques de finition et les caracteristiques des vaches ont ete renseignees par enquete individuelle. Des groupes de vaches et de finition ont ete definis par classification ascendante hierarchique et leurs effets sur la qualite de la viande ont ete definis par analyse de variance. Trois types de vache ont ete definis : des vaches jeunes et legeres a aptitude laitiere moyenne (J_leg ; n= 51) ; des vaches âgees et lourdes a bonne aptitude laitiere (V_lait ; n= 32) ; des vaches jeunes et lourdes a faible aptitude laitiere (J_lourde ; n= 13). Quatre pratiques de finition ont ete definies : finition longue (142 j) a...

La question de l'interdisciplinarite est aujourd'hui evoquee dans les plans d'actions... more La question de l'interdisciplinarite est aujourd'hui evoquee dans les plans d'actions strategiques de nombreuses universites. L'objectif de cette communication est de realiser un bilan de la gestion de l'interdisciplinarite dans une formation (master 2 ieme annee « MAN-IMAL ») ayant pour objectif de faire collaborer des etudiants ayant des formations initiales differentes (medecins, pharmaciens, veterinaires, scientifiques, ingenieurs) et provenant de differents continents afin de resoudre de maniere concertee des crises sanitaires impliquant l'homme, l'animal, l'alimentation et l'environnement. Notre reflexion s'est appuyee sur deux axes : l'etude de l'existence d'une interdisciplinarite dans cette formation, et un bilan des deux premieres annees montrant la vision des enseignants et celle des etudiants a l'aide d'entretiens collectifs semi-diriges. Certaines activites proposees (approche par probleme avec des etudes de ca...

Fourrages, 2017

Les benefices des prairies pour les exploitations et les territoires sont de plus en plus reconnu... more Les benefices des prairies pour les exploitations et les territoires sont de plus en plus reconnus. Pourtant, elles continuent a regresser a l'echelle nationale. Au nord de Rennes, en contexte periurbain, elles se sont toutefois maintenues ou ont mieux resiste qu'ailleurs entre 2000 et 2010. Ce constat pose la question du role qu'a pu jouer ce contexte periurbain dans ce maintien. Pour comprendre ces facteurs, une analyse historique de l'evolution de l'agriculture et une typologie des exploitations agricoles actuelles ont ete realisees. Sept types d'elevages laitiers ont ete definis dans cette zone ou l'elevage laitier predomine. Malgre un contexte pedoclimatique favorable a d'autres cultures, la prairie est presente dans toutes les exploitations laitieres (a des niveaux variables) du fait de la structuration d'une filiere industrielle laitiere forte et diversifiee liee a l'explosion d'un pole urbain valorisant de nouveaux modes de consomm...

Drawing pathways of cattle farms to identify the factors of grassland maintenance in the long ter... more Drawing pathways of cattle farms to identify the factors of grassland maintenance in the long term. 26. General meeting of the European Grassland Federation (EGF) on The Multiple Roles of Grassland in the European Bioeconomy

Les proprietes nutritionnelles et technologiques de la matiere grasse laitiere dependent de sa co... more Les proprietes nutritionnelles et technologiques de la matiere grasse laitiere dependent de sa composition et de la taille des globules gras qui la composent. Ces composantes sont maitrisables des l'elevage, les principaux leviers d'action etant lies a l'animal lui-meme ou a son alimentation. Cette revue bibliographique a pour objectif de decrire les mecanismes biochimiques et physiologiques a l'origine de la synthese et de la secretion de la matiere grasse laitiere, ainsi que les facteurs d'elevage permettant de les moduler et donc de modifier la composition et la taille des globules gras. Apres avoir resume les principales voies de synthese de la matiere grasse laitiere, les mecanismes supposes de sa secretion par le lactocyte sont explicites et les caracteristiques des globules gras (diametre, structure et composition de la membrane et du centre des globules gras) sont definies. Ensuite, leurs fonctionnalites technologiques, sensorielles et nutritionnelles son...

Preventive Veterinary Medicine, 2021

The behaviour and movement of lame dairy cows at pasture have been studied little, yet they could... more The behaviour and movement of lame dairy cows at pasture have been studied little, yet they could be relevant to improve the automatic detection of lameness in cows in pasture-based systems. Our aim in this study is to identify behavioural and movement variables of dairy cows at pasture that could discriminate lameness scores. Individual cow behaviours were predicted from accelerometer data and movements measured using GPS data. Sixty-eight dairy cows from three pasture-based commercial farms were equipped with a 3-D accelerometer and a GPS sensor fixed on a neck collar for 1-5 weeks, depending on the farm, in spring and summer 2018. A lameness score was assigned to each cow by a trained observer twice a week. Behaviours were predicted every 10 s based on accelerometer data, and then combined with the GPS position. Segmentation on behavioural time series was used to delineate each behavioural bout within each outdoor period. Thirty-seven behavioural and movement variables were then calculated from the behavioural bouts for each cow. A partial least square discriminant analysis was performed to identify the variables that best discriminate lameness scores. Time spent grazing, grazing bout duration, duration before lying down in the pasture, time spent resting, number of resting bouts, distance travelled during grazing, and dispersion were the most discriminant variables in the PLS-DA (VIP > 1). Severely lame cows spent 4.5 times less time grazing and almost twice as much time resting as their sound congeners, especially in the lying position. Exploratory behaviour was also reduced for both moderately and severely lame cows, resulting in 1.2 and 1.7 times less distance travelled respectively, especially during grazing. These variables could be used as additional variables to improve the performance of existing lameness detection devices in pasture-based systems.

Agricultural Systems, 2021

Abstract CONTEXT There is growing evidence that agroecology can reconcile the environmental, econ... more Abstract CONTEXT There is growing evidence that agroecology can reconcile the environmental, economic, and social pillars of agricultural sustainability. However, teaching and learning agroecology is challenging, especially since most agricultural graduate programs in Europe are not adapted to teach the diversity of its related practices. OBJECTIVE To improve agroecology learning, we built the online simulation game SEGAE. This article illustrates the game's relevance for learning agroecology. METHODS The game is based on a modeling framework that gamifies the implementation of agroecological practices in an integrated crop-livestock farm and assesses their impacts on sustainability. To do so, SEGAE is based on an output-oriented approach that represents impacts of practices on various indicators. These impacts are included in a matrix, which is associated with a dynamic graphical interface accessible to players. Two examples of game sessions were developed to illustrate the game's potential. RESULTS AND CONCLUSIONS In the first example, players can gain knowledge about agroecological practices by implementing practices that improve soil quality and assessing their impacts on sustainability. Results of this example place the farm's improved overall sustainability into perspective with its reduced food production potential. In the second example, players can improve their skills in transition management and acquire a systems approach by converting the farm to organic farming within five years. Results of this example prompt discussion of the steps needed to obtain organic certification and the coherence between crop and animal production needed to foster sustainability. SIGNIFICANCE SEGAE was designed to strengthen European training in agroecology, and active contributions from users would help to improve this tool, extend it to new farming systems and forge connections within the community of teachers working on agroecology.

Data in Brief, 2021

This article presents data designed by European researchers who performed a literature review and... more This article presents data designed by European researchers who performed a literature review and interpreted the results to determine impact factors of many agroecological practices on a wide variety of sustainability indicators. The impact factors are represented in a matrix that connects

Sensors, 2020

Our aim in this study was to investigate whether the behaviors of dairy cows on pasture, predicte... more Our aim in this study was to investigate whether the behaviors of dairy cows on pasture, predicted with accelerometer data and combined with GPS data, can be used to better understand the relationship between behaviors and pasture characteristics. During spring 2018, 26 Holstein cows were equipped with a 3D-accelerometer and a GPS sensor fixed on a neck-collar for five days. The cows grazed alternatively in permanent and in temporary grasslands. The structural elements, soil moisture, slope and botanical characteristics were identified. Behaviors were predicted every 10 s from the accelerometer data and combined with the GPS data. The time-budgets expressed in each characterized zone of 8 m × 8 m were calculated. The relation between the time-budgets and pasture characteristics was explored with a linear mixed model. In the permanent grassland, dairy cows spent more time under a tree to ruminate (p < 0.001) and to rest (p < 0.001) and more time to graze in areas with Holcus la...

Sustainability, 2020

Agroecology represents a pertinent option to improve the sustainability of agriculture. To promot... more Agroecology represents a pertinent option to improve the sustainability of agriculture. To promote its application, agroecological concepts should be taught to students and professionals in the agricultural sector. However, most agricultural courses are not adapted to teach these concepts due to little interactivity or interdisciplinarity, and a lack of a systems approach to farm management. Serious games help to fill these gaps by simulating complex models in which players can learn by doing. We thus developed a serious computer game, called SEGAE (SErious Game for AgroEcology learning), which represents a mixed crop-livestock farm and assesses impacts of farming practices on indicators related to environmental, economic, and social sustainability. Its pedagogical interest was evaluated through two types of surveys given to university students who played the game during a one-week workshop: A knowledge survey on agroecology, and a feedback survey based on flow theory. Results showe...

Computers and Electronics in Agriculture, 2019

Monitoring livestock behaviour can be a useful way to improve farm animal management and to detec... more Monitoring livestock behaviour can be a useful way to improve farm animal management and to detect individual health events. The use of automated systems that predict several daily behaviours from accelerometer data is growing and studies have often focused on the comparison of datamining classification methods. However, few studies have attempted to evaluate the effect of the step preceding the classification, namely accelerometer signal pre-processing. This study aimed to evaluate the effect of several pre-processing methods on the prediction of dairy cows behaviour from accelerometer data. Ten Holstein cows equipped with a threedimensional accelerometer fixed on a neck collar were simultaneously observed by two observers. Observed behaviours were predicted with decision tree using pre-processed accelerometer data as inputs. Different procedures were evaluated for each of these following pre-processing steps: signal filtering, signal segmentation and feature calculation. For signal filtering, low-pass filters and high-pass filters were considered. For signal segmentation, various window sizes and percentages of overlap between windows were implemented. Sixty-one features were computed. This resulted in 150 different combinations of pre-processing steps. For each combination a decision tree model predicting the observed behaviours was trained. The performance of each model to predict the observed behaviours was compared based on accuracy and F-score measures. The relative importance of each pre-processing configuration on the performance of prediction was evaluated with a linear regression model. The best configurations led to an accuracy of 0.95 and a F-score of 0.96 against 0.76 and 0.65 respectively with the worse combinations. The best combinations included a window size of 20 s and 30 s, with an overlap of 90% and no high-pass filter. High-pass filter had the most significant effect on the classification (P < 0.001), with a substantial decrease when it was applied. Performance of the classification was also significantly improved when increasing the percentage of overlapping (P < 0.001). The decline of the accuracy observed for the window size of 20 s without overlap was prevented when an overlap higher than 50% was applied. This suggested that overlap should be considered when there is not sufficient data available. No impact was found for the low-pas filter. In conclusion, the way of pre-processing the accelerometer signal deserves to be considered in the classification and adapted according to the aim and design of the study.

Foods, 2019

This trial aimed to integrate metadata that spread over farm-to-fork continuum of 110 Protected D... more This trial aimed to integrate metadata that spread over farm-to-fork continuum of 110 Protected Designation of Origin (PDO)Maine-Anjou cows and combine two statistical approaches that are chemometrics and supervised learning; to identify the potential predictors of beef tenderness analyzed using the instrumental Warner-Bratzler Shear force (WBSF). Accordingly, 60 variables including WBSF and belonging to 4 levels of the continuum that are farm-slaughterhouse-muscle-meat were analyzed by Partial Least Squares (PLS) and three decision tree methods (C&RT: classification and regression tree; QUEST: quick, unbiased, efficient regression tree and CHAID: Chi-squared Automatic Interaction Detection) to select the driving factors of beef tenderness and propose predictive decision tools. The former method retained 24 variables from 59 to explain 75% of WBSF. Among the 24 variables, six were from farm level, four from slaughterhouse level, 11 were from muscle level which are mostly protein bio...

Foods, 2019

The aim of study was to investigate the relationships between the characteristics of cull beef co... more The aim of study was to investigate the relationships between the characteristics of cull beef cows in the Rouge des Prés breed, finishing practices and physicochemical characteristics and sensory traits of Longissimus thoracis (LT) and Rectus abdominis (RA) muscles from 111 cows. On the basis of our surveys, which qualify at cow level the animal characteristics and finishing diet, clusters of cull cows and finishing practices are created and their effects tested on LT and RA meat quality. Old and heavy cows with good suckling ability (95 months, 466 kg and 7.1/10) are characterized by LT with larger fibers, and higher intramuscular fat content and fat-to-muscle ratio. Young and heavy cows with low suckling ability (54 months, 474 kg and 4.4/10) are characterized by LT and RA with lower MyHC IIx and higher MyHC IIa and MyHC I proportions. MyHC IIx and IIa proportions are lower and a* and b* color indices higher when cows are finished on pasture, probably related to grass diet and ph...

Http Www Theses Fr, 2006

Les effets de l’alimentation et de la variabilite individuelle des vaches laitieres (VL) sur la c... more Les effets de l’alimentation et de la variabilite individuelle des vaches laitieres (VL) sur la composition de la matiere grasse (MG) du lait son bien connus ce qui n’est pas le cas pour les caracteristiques physicochimiques de sa forme native, le globule gras (GG). Notre objectif etait de decrire les effets de ces facteurs d’elevage sur les caracteristiques du GG, d’analyser la relation entre les caracteristiques physiques du GG, les criteres de production du lait et le profil en acides gras (AG), et de caracteriser et distinguer les consequences d’une modification des proprietes des GG (taille et composition en AG) sur l’aptitude beurriere. L’herbe, comparee a l’ensilage de mais, diminue la taille des GG de 0,3 um en moyenne quelle que soit sa forme d’apport (pâturee, enrubannee ou ensilee). Elle ameliore selon une loi de reponse lineaire les proprietes nutritionnelles et rheologiques du beurre en lien avec une augmentation des teneurs en AG insatures. Enfin, les effets du fourrage et du niveau energetique de la ration sur le profil en AG son independants et se cumulent. Les VL de race de Normande ont en moyenne de plus gros GG (0,3 um) et ont tendance a avoir des activites de desaturation et de synthese de novo plus faible que les VL de race Holstein. La taille des GG n’evolue pas entre lactation et a tendance a diminuer avec le stade de lactation. Il existe une forte variabilite individuelle intra-race au niveau de la taille des GG et de la composition en AG. Les VL produisant de petits GG n’evolue pas entre lactation et a tendance a diminuer avec le stade de lactation. Il existe une forte variabilite individuelle intra-race au niveau de la taille des GG et de la composition en AG. Les VL produisant des petits GG se distinguent des VL produisant des gros GG par des activites de synthese de lait et de matieres proteiques, de desaturation des AG et de mobilisation calcique plus forts. Par contre, elles possedent des taux (TB et TP) et une activite de synthese de novo des AG plus faibles.

Journal of Dairy Science, 2006

Fresh grass in the cow diet improves the rheological and nutritional properties of butter. Howeve... more Fresh grass in the cow diet improves the rheological and nutritional properties of butter. However, the relationship between the proportion of fresh grass in the diet and these properties is still unknown. The objective of the study was to determine the relationship between the proportion of fresh grass in the diet and the properties of milk and butter. Four groups of 2 cows were fed 4 isoenergetic diets characterized by increasing amounts of fresh grass (0, 30, 60, and 100% dry matter of forage) according to a Youden square design. Energy levels were similar among all diets. Thus, no effect of mobilization was observed and the results were only due to the proportion of fresh grass in the diet. Milk yield linearly increased with the proportion of fresh grass in the diet (+0.21 kg/d per 10% of grass). Fat yield remained unchanged. Thus, by effect of dilution, increasing the proportion of fresh grass in the diet induced a linear decrease in fat content. Milk fat globule size decreased by 0.29 m when the proportion of grass reached 30% in the diet. Increasing the proportion of fresh grass in the diet induced a linear increase in unsaturated fatty acids percentages at the expense of saturated fatty acids. Relationships were +0.38, +0.12, +0.05 and −0.69 points/10% of fresh grass in the diet for C18:1 trans-11, C18:2 cis-9,trans-11, C18:3n-3, and C16:0, respectively. These modifications in fatty acid composition, and in particular in the spreadability index, C16:0/C18:1, were responsible for linear decreases in final melting temperature and solid fat content in butter fat, perceived in sensory analysis by a linear decrease in firmness in mouth. The nutritional value of butter was also linearly improved by the proportion of fresh grass in the diet by halving the atherogenicity index.

International audienceIn 2011, the French government initiated an ambitious experiment dedicated ... more International audienceIn 2011, the French government initiated an ambitious experiment dedicated to pedagogical innovations through the funding of 37 projects experimenting creative, collective, and cross-disciplinary approaches for innovative teaching. One of these projects, MAN-IMAL, was the first France-based international higher education degree programme exclusively based on the "One World, One Health" initiative. MAN-IMAL experimented: i) the use of ICTE; ii) a multidisciplinary approach developed by academics from Agricultural, Medical, and Veterinary Sciences; iii) as well as the interest of mixing students from various backgrounds (medical and veterinary studies, agricultural engineering, biological, and pharmacy studies). The developed training courses included several Bachelor-level modules and an international One Health post-graduate degree entirely taught in English, the latter experimenting a multicultural approach. The teachers involved in the MAN-IMAL prog...

International audienceLa transition agroécologique initiée depuis les années 1990 vise à développ... more International audienceLa transition agroécologique initiée depuis les années 1990 vise à développer de nouveaux systèmes d'élevage qui optimisent la productivité tout en améliorant la santé des animaux et en diminuant les impacts environnementaux. Dans le cas particulier de l'élevage de bovins laitiers, la valorisation des prairies par le pâturage devrait permettre de répondre à plusieurs piliers de l'agroéocologie. Cette pratique est néanmoins complexe à mettre en oeuvre et une gestion inadaptée peut compromettre les bénéfices attendus (valorisation de l'herbe non optimale, stress des animaux sur les prairies, etc.). Dans le cadre de l'élevage de précision, des outils se développent pour améliorer les performances des exploitations mais ceux à destination du pâturage restent marginaux et de plus-value discutable. A ce propos, le comportement et la position des vaches laitières devraient servir de support au développement de nouveaux outils puisqu'ils sont de...

Computers and Electronics in Agriculture, 2022

L’objectif de ce travail a ete d’evaluer le lien entre le type de vaches de reforme de l’AOP Main... more L’objectif de ce travail a ete d’evaluer le lien entre le type de vaches de reforme de l’AOP Maine Anjou, les pratiques de finition et la qualite de la viande. Pour cela, les muscles Longissimus Thoracis (LT) et Rectus Abdominis (RA) de 111 vaches de reforme de race Rouge des Pres ont ete preleves et caracterises physico- chimiquement et sensoriellement (RA uniquement). Les pratiques de finition et les caracteristiques des vaches ont ete renseignees par enquete individuelle. Des groupes de vaches et de finition ont ete definis par classification ascendante hierarchique et leurs effets sur la qualite de la viande ont ete definis par analyse de variance. Trois types de vache ont ete definis : des vaches jeunes et legeres a aptitude laitiere moyenne (J_leg ; n= 51) ; des vaches âgees et lourdes a bonne aptitude laitiere (V_lait ; n= 32) ; des vaches jeunes et lourdes a faible aptitude laitiere (J_lourde ; n= 13). Quatre pratiques de finition ont ete definies : finition longue (142 j) a...

La question de l'interdisciplinarite est aujourd'hui evoquee dans les plans d'actions... more La question de l'interdisciplinarite est aujourd'hui evoquee dans les plans d'actions strategiques de nombreuses universites. L'objectif de cette communication est de realiser un bilan de la gestion de l'interdisciplinarite dans une formation (master 2 ieme annee « MAN-IMAL ») ayant pour objectif de faire collaborer des etudiants ayant des formations initiales differentes (medecins, pharmaciens, veterinaires, scientifiques, ingenieurs) et provenant de differents continents afin de resoudre de maniere concertee des crises sanitaires impliquant l'homme, l'animal, l'alimentation et l'environnement. Notre reflexion s'est appuyee sur deux axes : l'etude de l'existence d'une interdisciplinarite dans cette formation, et un bilan des deux premieres annees montrant la vision des enseignants et celle des etudiants a l'aide d'entretiens collectifs semi-diriges. Certaines activites proposees (approche par probleme avec des etudes de ca...

Fourrages, 2017

Les benefices des prairies pour les exploitations et les territoires sont de plus en plus reconnu... more Les benefices des prairies pour les exploitations et les territoires sont de plus en plus reconnus. Pourtant, elles continuent a regresser a l'echelle nationale. Au nord de Rennes, en contexte periurbain, elles se sont toutefois maintenues ou ont mieux resiste qu'ailleurs entre 2000 et 2010. Ce constat pose la question du role qu'a pu jouer ce contexte periurbain dans ce maintien. Pour comprendre ces facteurs, une analyse historique de l'evolution de l'agriculture et une typologie des exploitations agricoles actuelles ont ete realisees. Sept types d'elevages laitiers ont ete definis dans cette zone ou l'elevage laitier predomine. Malgre un contexte pedoclimatique favorable a d'autres cultures, la prairie est presente dans toutes les exploitations laitieres (a des niveaux variables) du fait de la structuration d'une filiere industrielle laitiere forte et diversifiee liee a l'explosion d'un pole urbain valorisant de nouveaux modes de consomm...

Drawing pathways of cattle farms to identify the factors of grassland maintenance in the long ter... more Drawing pathways of cattle farms to identify the factors of grassland maintenance in the long term. 26. General meeting of the European Grassland Federation (EGF) on The Multiple Roles of Grassland in the European Bioeconomy

Les proprietes nutritionnelles et technologiques de la matiere grasse laitiere dependent de sa co... more Les proprietes nutritionnelles et technologiques de la matiere grasse laitiere dependent de sa composition et de la taille des globules gras qui la composent. Ces composantes sont maitrisables des l'elevage, les principaux leviers d'action etant lies a l'animal lui-meme ou a son alimentation. Cette revue bibliographique a pour objectif de decrire les mecanismes biochimiques et physiologiques a l'origine de la synthese et de la secretion de la matiere grasse laitiere, ainsi que les facteurs d'elevage permettant de les moduler et donc de modifier la composition et la taille des globules gras. Apres avoir resume les principales voies de synthese de la matiere grasse laitiere, les mecanismes supposes de sa secretion par le lactocyte sont explicites et les caracteristiques des globules gras (diametre, structure et composition de la membrane et du centre des globules gras) sont definies. Ensuite, leurs fonctionnalites technologiques, sensorielles et nutritionnelles son...

Preventive Veterinary Medicine, 2021

The behaviour and movement of lame dairy cows at pasture have been studied little, yet they could... more The behaviour and movement of lame dairy cows at pasture have been studied little, yet they could be relevant to improve the automatic detection of lameness in cows in pasture-based systems. Our aim in this study is to identify behavioural and movement variables of dairy cows at pasture that could discriminate lameness scores. Individual cow behaviours were predicted from accelerometer data and movements measured using GPS data. Sixty-eight dairy cows from three pasture-based commercial farms were equipped with a 3-D accelerometer and a GPS sensor fixed on a neck collar for 1-5 weeks, depending on the farm, in spring and summer 2018. A lameness score was assigned to each cow by a trained observer twice a week. Behaviours were predicted every 10 s based on accelerometer data, and then combined with the GPS position. Segmentation on behavioural time series was used to delineate each behavioural bout within each outdoor period. Thirty-seven behavioural and movement variables were then calculated from the behavioural bouts for each cow. A partial least square discriminant analysis was performed to identify the variables that best discriminate lameness scores. Time spent grazing, grazing bout duration, duration before lying down in the pasture, time spent resting, number of resting bouts, distance travelled during grazing, and dispersion were the most discriminant variables in the PLS-DA (VIP > 1). Severely lame cows spent 4.5 times less time grazing and almost twice as much time resting as their sound congeners, especially in the lying position. Exploratory behaviour was also reduced for both moderately and severely lame cows, resulting in 1.2 and 1.7 times less distance travelled respectively, especially during grazing. These variables could be used as additional variables to improve the performance of existing lameness detection devices in pasture-based systems.

Agricultural Systems, 2021

Abstract CONTEXT There is growing evidence that agroecology can reconcile the environmental, econ... more Abstract CONTEXT There is growing evidence that agroecology can reconcile the environmental, economic, and social pillars of agricultural sustainability. However, teaching and learning agroecology is challenging, especially since most agricultural graduate programs in Europe are not adapted to teach the diversity of its related practices. OBJECTIVE To improve agroecology learning, we built the online simulation game SEGAE. This article illustrates the game's relevance for learning agroecology. METHODS The game is based on a modeling framework that gamifies the implementation of agroecological practices in an integrated crop-livestock farm and assesses their impacts on sustainability. To do so, SEGAE is based on an output-oriented approach that represents impacts of practices on various indicators. These impacts are included in a matrix, which is associated with a dynamic graphical interface accessible to players. Two examples of game sessions were developed to illustrate the game's potential. RESULTS AND CONCLUSIONS In the first example, players can gain knowledge about agroecological practices by implementing practices that improve soil quality and assessing their impacts on sustainability. Results of this example place the farm's improved overall sustainability into perspective with its reduced food production potential. In the second example, players can improve their skills in transition management and acquire a systems approach by converting the farm to organic farming within five years. Results of this example prompt discussion of the steps needed to obtain organic certification and the coherence between crop and animal production needed to foster sustainability. SIGNIFICANCE SEGAE was designed to strengthen European training in agroecology, and active contributions from users would help to improve this tool, extend it to new farming systems and forge connections within the community of teachers working on agroecology.

Data in Brief, 2021

This article presents data designed by European researchers who performed a literature review and... more This article presents data designed by European researchers who performed a literature review and interpreted the results to determine impact factors of many agroecological practices on a wide variety of sustainability indicators. The impact factors are represented in a matrix that connects

Sensors, 2020

Our aim in this study was to investigate whether the behaviors of dairy cows on pasture, predicte... more Our aim in this study was to investigate whether the behaviors of dairy cows on pasture, predicted with accelerometer data and combined with GPS data, can be used to better understand the relationship between behaviors and pasture characteristics. During spring 2018, 26 Holstein cows were equipped with a 3D-accelerometer and a GPS sensor fixed on a neck-collar for five days. The cows grazed alternatively in permanent and in temporary grasslands. The structural elements, soil moisture, slope and botanical characteristics were identified. Behaviors were predicted every 10 s from the accelerometer data and combined with the GPS data. The time-budgets expressed in each characterized zone of 8 m × 8 m were calculated. The relation between the time-budgets and pasture characteristics was explored with a linear mixed model. In the permanent grassland, dairy cows spent more time under a tree to ruminate (p < 0.001) and to rest (p < 0.001) and more time to graze in areas with Holcus la...

Sustainability, 2020

Agroecology represents a pertinent option to improve the sustainability of agriculture. To promot... more Agroecology represents a pertinent option to improve the sustainability of agriculture. To promote its application, agroecological concepts should be taught to students and professionals in the agricultural sector. However, most agricultural courses are not adapted to teach these concepts due to little interactivity or interdisciplinarity, and a lack of a systems approach to farm management. Serious games help to fill these gaps by simulating complex models in which players can learn by doing. We thus developed a serious computer game, called SEGAE (SErious Game for AgroEcology learning), which represents a mixed crop-livestock farm and assesses impacts of farming practices on indicators related to environmental, economic, and social sustainability. Its pedagogical interest was evaluated through two types of surveys given to university students who played the game during a one-week workshop: A knowledge survey on agroecology, and a feedback survey based on flow theory. Results showe...

Computers and Electronics in Agriculture, 2019

Monitoring livestock behaviour can be a useful way to improve farm animal management and to detec... more Monitoring livestock behaviour can be a useful way to improve farm animal management and to detect individual health events. The use of automated systems that predict several daily behaviours from accelerometer data is growing and studies have often focused on the comparison of datamining classification methods. However, few studies have attempted to evaluate the effect of the step preceding the classification, namely accelerometer signal pre-processing. This study aimed to evaluate the effect of several pre-processing methods on the prediction of dairy cows behaviour from accelerometer data. Ten Holstein cows equipped with a threedimensional accelerometer fixed on a neck collar were simultaneously observed by two observers. Observed behaviours were predicted with decision tree using pre-processed accelerometer data as inputs. Different procedures were evaluated for each of these following pre-processing steps: signal filtering, signal segmentation and feature calculation. For signal filtering, low-pass filters and high-pass filters were considered. For signal segmentation, various window sizes and percentages of overlap between windows were implemented. Sixty-one features were computed. This resulted in 150 different combinations of pre-processing steps. For each combination a decision tree model predicting the observed behaviours was trained. The performance of each model to predict the observed behaviours was compared based on accuracy and F-score measures. The relative importance of each pre-processing configuration on the performance of prediction was evaluated with a linear regression model. The best configurations led to an accuracy of 0.95 and a F-score of 0.96 against 0.76 and 0.65 respectively with the worse combinations. The best combinations included a window size of 20 s and 30 s, with an overlap of 90% and no high-pass filter. High-pass filter had the most significant effect on the classification (P < 0.001), with a substantial decrease when it was applied. Performance of the classification was also significantly improved when increasing the percentage of overlapping (P < 0.001). The decline of the accuracy observed for the window size of 20 s without overlap was prevented when an overlap higher than 50% was applied. This suggested that overlap should be considered when there is not sufficient data available. No impact was found for the low-pas filter. In conclusion, the way of pre-processing the accelerometer signal deserves to be considered in the classification and adapted according to the aim and design of the study.

Foods, 2019

This trial aimed to integrate metadata that spread over farm-to-fork continuum of 110 Protected D... more This trial aimed to integrate metadata that spread over farm-to-fork continuum of 110 Protected Designation of Origin (PDO)Maine-Anjou cows and combine two statistical approaches that are chemometrics and supervised learning; to identify the potential predictors of beef tenderness analyzed using the instrumental Warner-Bratzler Shear force (WBSF). Accordingly, 60 variables including WBSF and belonging to 4 levels of the continuum that are farm-slaughterhouse-muscle-meat were analyzed by Partial Least Squares (PLS) and three decision tree methods (C&RT: classification and regression tree; QUEST: quick, unbiased, efficient regression tree and CHAID: Chi-squared Automatic Interaction Detection) to select the driving factors of beef tenderness and propose predictive decision tools. The former method retained 24 variables from 59 to explain 75% of WBSF. Among the 24 variables, six were from farm level, four from slaughterhouse level, 11 were from muscle level which are mostly protein bio...

Foods, 2019

The aim of study was to investigate the relationships between the characteristics of cull beef co... more The aim of study was to investigate the relationships between the characteristics of cull beef cows in the Rouge des Prés breed, finishing practices and physicochemical characteristics and sensory traits of Longissimus thoracis (LT) and Rectus abdominis (RA) muscles from 111 cows. On the basis of our surveys, which qualify at cow level the animal characteristics and finishing diet, clusters of cull cows and finishing practices are created and their effects tested on LT and RA meat quality. Old and heavy cows with good suckling ability (95 months, 466 kg and 7.1/10) are characterized by LT with larger fibers, and higher intramuscular fat content and fat-to-muscle ratio. Young and heavy cows with low suckling ability (54 months, 474 kg and 4.4/10) are characterized by LT and RA with lower MyHC IIx and higher MyHC IIa and MyHC I proportions. MyHC IIx and IIa proportions are lower and a* and b* color indices higher when cows are finished on pasture, probably related to grass diet and ph...

Http Www Theses Fr, 2006

Les effets de l’alimentation et de la variabilite individuelle des vaches laitieres (VL) sur la c... more Les effets de l’alimentation et de la variabilite individuelle des vaches laitieres (VL) sur la composition de la matiere grasse (MG) du lait son bien connus ce qui n’est pas le cas pour les caracteristiques physicochimiques de sa forme native, le globule gras (GG). Notre objectif etait de decrire les effets de ces facteurs d’elevage sur les caracteristiques du GG, d’analyser la relation entre les caracteristiques physiques du GG, les criteres de production du lait et le profil en acides gras (AG), et de caracteriser et distinguer les consequences d’une modification des proprietes des GG (taille et composition en AG) sur l’aptitude beurriere. L’herbe, comparee a l’ensilage de mais, diminue la taille des GG de 0,3 um en moyenne quelle que soit sa forme d’apport (pâturee, enrubannee ou ensilee). Elle ameliore selon une loi de reponse lineaire les proprietes nutritionnelles et rheologiques du beurre en lien avec une augmentation des teneurs en AG insatures. Enfin, les effets du fourrage et du niveau energetique de la ration sur le profil en AG son independants et se cumulent. Les VL de race de Normande ont en moyenne de plus gros GG (0,3 um) et ont tendance a avoir des activites de desaturation et de synthese de novo plus faible que les VL de race Holstein. La taille des GG n’evolue pas entre lactation et a tendance a diminuer avec le stade de lactation. Il existe une forte variabilite individuelle intra-race au niveau de la taille des GG et de la composition en AG. Les VL produisant de petits GG n’evolue pas entre lactation et a tendance a diminuer avec le stade de lactation. Il existe une forte variabilite individuelle intra-race au niveau de la taille des GG et de la composition en AG. Les VL produisant des petits GG se distinguent des VL produisant des gros GG par des activites de synthese de lait et de matieres proteiques, de desaturation des AG et de mobilisation calcique plus forts. Par contre, elles possedent des taux (TB et TP) et une activite de synthese de novo des AG plus faibles.

Journal of Dairy Science, 2006

Fresh grass in the cow diet improves the rheological and nutritional properties of butter. Howeve... more Fresh grass in the cow diet improves the rheological and nutritional properties of butter. However, the relationship between the proportion of fresh grass in the diet and these properties is still unknown. The objective of the study was to determine the relationship between the proportion of fresh grass in the diet and the properties of milk and butter. Four groups of 2 cows were fed 4 isoenergetic diets characterized by increasing amounts of fresh grass (0, 30, 60, and 100% dry matter of forage) according to a Youden square design. Energy levels were similar among all diets. Thus, no effect of mobilization was observed and the results were only due to the proportion of fresh grass in the diet. Milk yield linearly increased with the proportion of fresh grass in the diet (+0.21 kg/d per 10% of grass). Fat yield remained unchanged. Thus, by effect of dilution, increasing the proportion of fresh grass in the diet induced a linear decrease in fat content. Milk fat globule size decreased by 0.29 m when the proportion of grass reached 30% in the diet. Increasing the proportion of fresh grass in the diet induced a linear increase in unsaturated fatty acids percentages at the expense of saturated fatty acids. Relationships were +0.38, +0.12, +0.05 and −0.69 points/10% of fresh grass in the diet for C18:1 trans-11, C18:2 cis-9,trans-11, C18:3n-3, and C16:0, respectively. These modifications in fatty acid composition, and in particular in the spreadability index, C16:0/C18:1, were responsible for linear decreases in final melting temperature and solid fat content in butter fat, perceived in sensory analysis by a linear decrease in firmness in mouth. The nutritional value of butter was also linearly improved by the proportion of fresh grass in the diet by halving the atherogenicity index.