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M Odonovan - One of the best experts on this subject based on the ideXlab platform.
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the effect of pasture allowance and concentrate supplementation type on milk production performance and dry matter intake of autumn calving dairy cows in early lactation
Livestock Science, 2010Co-Authors: R G Pulido, Carla Jara, J P Smulders, Patricio Orellana, Felix Wittwer, R Munoz, Oscar Balocchi, M OdonovanAbstract:Abstract This study was undertaken to evaluate the influence of daily pasture allowance and concentrate type on milk production performance, dry matter intake, Grazing Behavior and blood and urinary metabolites of autumn-calving dairy cows in early lactation. The study lasted 61 days using 28 Holstein Friesian cows. Prior to experimental treatment, milk production averaged 23.1 kg/day (± 3.64 kg/day) and mean live weight was 595 kg (± 48.1 kg). The four dietary treatments were a combination of two pasture allowances above ground level (low, 25.5 vs. high, 38.5 kg of dry matter/cow/day) and two concentrate types offered at the level of 5 kg/cow/day (corn-based concentrate vs. sugar beet pulp-based concentrate). Total dry matter intake of individual cows was estimated using the n-alkenes method and milk composition was analyzed weekly using infrared spectroscopy (Foss 4300 Milko-scan). Pasture allowance significantly (P 0.05) on milk production, milk fat (3.73%) or protein (3.09%). Pasture dry matter (DM) intake and total DM intake (kg/day) increased from 9.6 to 11.1 and from 13.9 to 15.4 with increased in pasture allowance (P 0.05). High pasture allowance increased (P
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effect of restricted access time to pasture on dairy cow milk production Grazing Behavior and dry matter intake
Journal of Dairy Science, 2009Co-Authors: E. Kennedy, M Mcevoy, J.p. Murphy, M OdonovanAbstract:Abstract The objective of this experiment was to investigate the effect of restricting pasture access time on milk production and composition, body weight and body condition score change, dry matter intake, and Grazing Behavior of autumn calving dairy cows in midlactation. Fifty-two (19 primiparous and 33 multiparous) Holstein-Friesian dairy cows (mean calving date, August 17 ± 91.2 d) were randomly assigned to a 4-treatment (n = 13) randomized block design Grazing study. The 4 Grazing treatments were: (i) full-time access to pasture (22H; control), (ii) 9-h access to pasture (9H), (iii) two 4.5-h periods of access to pasture after both milkings (2 × 4.5H), and (iv) two 3-h periods of access to pasture after both milkings (2 × 3H). Experimental treatments were imposed from March 7 to April 6, 2007 (31 d). The preGrazing herbage mass of swards offered to all treatments was 1,268 kg of dry matter/ha, and sward organic matter digestibility was 86.4%, indicating high-quality swards conducive to high dry matter intake. Swards where animals had 22H and 2 × 4.5H access to pasture had the lowest postGrazing sward heights (3.5 cm), reflecting the greatest levels of sward utilization. After the experimental period, there were no differences in milk production; however, the 2 × 3H animals tended to have lower milk protein concentration (−0.17%) compared with 22H animals. Furthermore, dry matter intake of the 9H animals was lower than 22H animals. Although restricting access time to pasture decreased Grazing time, animals compensated by increasing their intake/minute and intake/bite. Restricting pasture access time resulted in much greater Grazing efficiency, because the 9H, 2 × 4.5H, and 2 × 3H treatments spent a greater proportion of their time at pasture Grazing (81, 81, and 96%, respectively) than 22H animals (42%). Results of this study indicate that allocating animals restricted access to pasture does not significantly affect milk production. This study also found that the total access time should be greater than 6 h and that perhaps needs to be divided into 2 periods.
Remy Delagarde - One of the best experts on this subject based on the ideXlab platform.
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Metabolic and productive response and Grazing Behavior of lactating dairy cows supplemented with high moisture maize or cracked wheat Grazing at two herbage allowances in spring
Animals, 2021Co-Authors: Verónica Merino, Oscar Balocchi, Remy Delagarde, Lorena Leichtle, Francisco Lanuza, Julián Parga, Miguel Ruiz-albarrán, M. Jordana Rivero, Rubén PulidoAbstract:The aim was to determine the effect of the herbage allowance (HA) and supplement type (ST) on dry matter intake (DMI), milk production and composition, Grazing Behavior, rumen function, and blood metabolites of Grazing dairy cows in the spring season. Experiment I: 64 Holstein Friesian dairy cows were distributed in a factorial design that tested two levels of daily HA (20 and 30 kg of dry matter (DM) per cow) and two ST (high moisture maize (HMM) and cracked wheat (CW)) distributed in two daily rations (3.5 kg DM/cow/day). Experiment II: four mid-lactation rumen cannulated cows, supplemented with either HMM or CW and managed with the two HAs, were distributed in a Latin square design of 4 × 4, for four 14-d periods to assess ruminal fermentation parameters. HA had no effect on milk production (averaging 23.6 kg/day) or milk fat and protein production (823 g/day and 800 g/day, respectively). Cows supplemented with CW had greater protein concentration (+1.2 g/kg). Herbage DMI averaged 14.17 kg DM/cow.day and total DMI averaged 17.67 kg DM/cow.day and did not differ between treatments. Grazing Behavior activities (Grazing, rumination, and idling times) and body condition score (BCS) were not affected by HA or ST. Milk and plasma urea concentration increased under the high HA (+0.68 mmol/L and +0.90 mmol/L, respectively). Cows supplemented with HMM had lower milk and plasma urea concentrations (0.72 mmol/L and 0.76 mmol/L less, respectively) and tended (p = 0.054) to have higher plasma β-hydroxybutyrate. Ruminal parameters did not differ between treatments.
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Meta-analysis of the effect of pasture allowance on pasture intake, milk production, and Grazing Behavior of dairy cows Grazing temperate grasslands
Journal of Dairy Science, 2013Co-Authors: Lucio Alberto Perez Prieto, Remy DelagardeAbstract:Daily pasture allowance (PA) is defined as the product of preGrazing pasture mass and offered area, and is the major Grazing management factor determining pasture utilization per unit area and daily performance of Grazing dairy cows. The objective of the present study was to perform a meta-analysis reviewing the effect of PA on pasture intake, milk production, milk composition, and Grazing Behavior of dairy cows. Experiments studying the effect of PA on pasture intake or milk production, which eventually included milk composition or Grazing Behavior data, or both, were selected to create a database. Papers were selected only if at least 2 PA were compared under the same experimental conditions, particularly the same pasture mass (i.e., where PA levels were only obtained through changes in daily offered area). The final database included 97 PA comparisons reported in 56 papers. For analytical purposes, the database was subdivided into 3 subsets that varied according to the estimation height (EH) at which PA was determined; that is, PA above ground level (PA0 subset), PA above 2.5 to 3.5cm (PA3 subset), and PA above 4 to 5cm (PA5 subset). Statistical analyses were conducted independently on the PA0, PA3, and PA5 subsets and on the whole database (global analysis) by using linear and nonlinear mixed-model procedures. The curves, either exponential, quadratic, or linear, describing the effects of PA on pasture intake, milk production, or Grazing Behavior of dairy cows are conceptually similar, whatever the EH. The equations describing these curves are, however, specific for each EH. Accordingly, from typical low to high PA, the increase in pasture intake (0.13 vs. 0.21 vs. 0.28kg/kg of PA), milk production (0.11 vs. 0.17 vs. 0.24kg/kg of PA), and milk solids production (0.008 vs. 0.010 vs. 0.013kg/kg of PA) per kilogram of increase in PA was lower for PA0 than for PA3, and for PA3 than for PA5. Grazing time increased from low to medium PA and did not vary from medium to high PA. Pasture intake rate seemed to increase from low to medium PA because of greater bite mass, whereas it increased from medium to high PA because of greater biting rate. The present meta-analysis demonstrated that the general relationship between PA and any dependent variable is quite strong and independent of EH. This suggests no specific relationship for some parts of the world or methodology approach, with a high portability of the global equations calculated here. These results are useful for improving Grazing management and modeling on pasture-based dairy systems.
R Delagarde - One of the best experts on this subject based on the ideXlab platform.
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substitution rate and milk yield response to corn silage supplementation of late lactation dairy cows Grazing low mass pastures at 2 daily allowances in autumn
Journal of Dairy Science, 2011Co-Authors: L A Perezprieto, J L Peyraud, R DelagardeAbstract:Feed costs in dairy production systems may be decreased by extending the Grazing season to periods such as autumn when Grazing low-mass pastures is highly probable. The aim of this autumn study was to determine the effect of corn silage supplementation [0 vs. 8 kg of dry matter (DM) of a mixture 7:1 of corn silage and soybean meal] on pasture intake (PI), milk production, and Grazing Behavior of dairy cows Grazing low-mass ryegrass pastures at 2 daily pasture allowances (PA; low PA = 18 vs. high PA = 30 kg of DM/cow above 2.5 cm). Twelve multiparous Holstein cows were used in a 4 × 4 Latin square design with 14-d periods. Pre-Grazing pasture mass and pre-Grazing plate meter pasture height averaged 1.8 t of DM/ha (above 2.5 cm) and 6.3 cm, respectively. The quality of the offered pasture (above 2.5 cm) was low because of dry conditions before and during the experiment (crude protein = 11.5% of DM; net energy for lactation = 5.15 MJ/kg of DM; organic matter digestibility = 61.9%). The interaction between PA and supplementation level was significant for PI but not for milk production. Supplementation decreased PI from 11.6 to 7.6 kg of DM/d at low PA and from 13.1 to 7.3 kg of DM/d at high PA. The substitution rate was, therefore, lower at low than at high PA (0.51 vs. 0.75). Pasture intake increased with increasing PA in unsupplemented treatments, and was not affected by PA in supplemented treatments. Milk production averaged 13.5 kg/d and was greater at high than at low PA (+1.4 kg/d) and in supplemented than unsupplemented treatments (+5.2 kg/d). Milk fat concentration averaged 4.39% and was similar between treatments. Milk protein concentration increased from 3.37 to 3.51% from unsupplemented to supplemented treatments, and did not vary according to PA. Grazing Behavior parameters were only affected by supplementation. On average, daily Grazing time decreased (539 vs. 436 min) and daily ruminating time increased (388 vs. 486 min) from 0 to 8 kg of supplement DM. The PI rate was 6 g of DM/min lower in supplemented than in unsupplemented treatments (17 vs. 23 g of DM/min). The high milk yield response to supplementation may be related to a cumulative effect of the low-mass pasture (low PI) and the low quality of the pasture, which strongly limited energy supply in unsupplemented cows.
D Pacheco - One of the best experts on this subject based on the ideXlab platform.
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milk production and composition nitrogen utilization and Grazing Behavior of late lactation dairy cows as affected by time of allocation of a fresh strip of pasture
Journal of Dairy Science, 2017Co-Authors: Ronaldo Viba, P Gregorini, Michael H. Tavendale, H Schwendel, K Lowe, Do Otte, D PachecoAbstract:Eighty late-lactation dairy cows were used to examine the effects of allocating a new pasture strip of a sward based on ryegrass (Lolium perenne L.) in the morning (a.m.; ∼0730 h) or in the afternoon (p.m.; ∼1530 h) on milk production and composition, nitrogen (N) utilization, and Grazing Behavior. Cows grazed the same pasture strips for 24 h and were offered the same daily herbage allowance. Herbage composition differed among treatments; p.m. herbage had greater dry matter (DM; 22.7 vs. 19.9%), organic matter (OM; 89.5 vs. 88.9%), and water-soluble carbohydrate (10.9 vs. 7.6%) concentrations and lesser crude protein (20.5 vs. 22.2%) and neutral detergent fiber (48.8 vs. 50.4%) concentrations compared with a.m. herbage. Total fatty acids (FA), α-linolenic acid, and polyunsaturated FA (PUFA) were greater in a.m. herbage, whereas monounsaturated FA were greater in p.m. herbage. Estimates of herbage DM intake did not differ among treatments. Daily milk yields and milk fat and milk protein concentrations were similar among treatments, whereas milk fat (684 vs. 627 g/cow), milk protein (545 vs. 505 g/cow), and milk solids (milk fat + milk protein) yields (1,228 vs. 1,132 g/cow) tended to be greater for cows on p.m. herbage. Rumenic acid and total PUFA in milk were greater for cows on a.m. herbage, whereas oleic acid was greater for cows on p.m. herbage. Estimates of urinary N excretion (g/d) did not differ among treatments, but urinary N concentrations were greater for cows on a.m. herbage (5.85 vs. 5.36 g/L). Initial herbage mass (HM) available (kg of DM/ha) and instantaneous HM disappearance rates (kg of DM/ha and kg of DM/h) did not differ, but fractional disappearance rates (0.56 vs. 0.74 per hour for a.m. vs. p.m., respectively) differed. Under the current conditions, timing of pasture strip allocation altered the herbage nutrient supply to cows; allocating a fresh strip of pasture later in the day resulted in moderate increases in milk and milk solids yields in late-lactation dairy cows. Conversely, a greater concentration of precursor FA in a.m. herbage resulted in a greater concentration of beneficial FA in milk, compared with cows on p.m. herbage.
Andriamandroso Andriamasinoro - One of the best experts on this subject based on the ideXlab platform.
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Cattle Grazing dynamics under contrasted pasture characteristics at temporal and spatial scales
Université de Liège Liège Belgique, 2017Co-Authors: Andriamandroso AndriamasinoroAbstract:Grassland constitutes an important and a low-cost food source for Grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, Grazing is a normal Behavior displayed in an attempt to eat the amount of forage to fulfill their nutritive requirements for maintenance and production. It is the most time-consumed activity of cows reared in pasture-based systems. With the increase of herd size, on one hand, farmers have been constrained to integrate innovative tools and techniques, such as milking robot, to improve the production system in particular to reduce the labor cost. On the other hand, such change might reduce time allocated for Grazing on pasture. However pasture-based systems constitute a real pillar for sustainability as they are socially acceptable and environmentally profitable as they play an important role on ecosystem services and biodiversity provision. Studying Grazing processes at individual level, which finally is the key point of animal-plant interactions, is a valuable research domain to enhance the knowledge about this mechanism and to feed decision support tools. This thesis aimed to link the changes in pasture characteristics to the Grazing Behavior of cattle in order to better understand the Grazing strategy under different pasture characteristics and forage allowances. To allow an individual monitoring, sensor technology has integrated within farms and livestock researches to monitor many physical variables, inducing the emergence of precision livestock farming approach. Different types of sensors were designed, and already commercialized for some, primarily for physiological status detections such as heat, parturition or diseases. Grazing Behaviors could be monitored using pressure, electromyography, acoustic or accelerometric sensors by classifying posture and movements of the animal into unitary Behaviors (Grazing, ruminating, resting, walking, etc.) and finer Behavior such as chews and bites through jaw movements’ detection. When compared to real observation, detection accuracies of these Behaviors were variable according to the type of sensor, its position on the animal during data acquisition on pasture, the data recording frequency, the time-window and the method dedicated to the post-recording data analysis. State-of-the-art analysis demonstrated a great performance of accelerometers for unitary Behaviors and bites detection. An inertial measurement unit, integrating accelerometer, gyroscope and location sensors, was used for recording cattle movements during Grazing at high sampling rate (100Hz). It allows a correct detection of grass intake and rumination Behaviors with an average accuracy of 91% using 1-second time-window when calibrating and validating the detection algorithm. Deeper analysis of accelerometric signal allowed us to detect bites and chews performed during Grazing and ruminating. Effects of pasture heights on Grazing bites characteristics were differentiated by a higher frequency when pasture is at a lower height. Finally when combined to geographical information, a similar pattern was observed for cattle Grazing on the same spot confirming their herd movement during Grazing in terms of bites location. Differences were visible under different pasture heights but not significant. Such bites location, combined with continuous monitoring of cattle Behaviors, through use of sensors, should be furtherly linked with more pasture characteristics, if possible with the same accuracy, and monitored on longer period in order to obtain a complete coverage of cattle Grazing strategy and the effect of contrasted environment in order to purpose valuable tool for a better Grazing management.La prairie constitue une importante ressource alimentaire, et à moindre coût, pour les ruminants. Une gestion optimale de cette ressource doit considérer à la fois la productivité du fourrage et les besoins des animaux. Pour les bovins, le pâturage est un comportement normal d’ingestion de fourrage dans le but de satisfaire leurs besoins nutritionnels d’entretien et de production. Il s’agit du comportement qui occupe le plus de temps parmi les activités journalières des bovins en prairie. Avec l’augmentation de la taille des troupeaux, d’une part, les éleveurs ont été contraints d’intégrer des pratiques innovantes, telles que le robot de traite, par exemple, pour améliorer le système de production et notamment pour diminuer le coût en main d’œuvre. D’autre part, de tels changements ont eu tendance à réduire le temps alloué au pâturage des animaux. Cependant les systèmes de production à base de pâturage sont actuellement perçus comme un pilier du développement durable. En effet, ils suscitent un regain d’intérêt au niveau de la société et surtout sont bénéfiques pour l’environnement sachant que la prairie joue un rôle important dans la fourniture de services écosystémiques et de biodiversité. Etudier le processus de pâturage à l’échelle de l’individu, qui est un point-clé dans l’interaction plante-animal, constitue un domaine de recherche d’intérêt pour approfondir les connaissances à propos de ce mécanisme et pour développer des outils d’aide à la décision. La présente thèse a pour but de déterminer les liens entre les changements des caractéristiques du pâturage et le comportement des bovins afin de mieux comprendre les stratégies adoptées par les vaches dans un environnement prairial contrasté. Pour permettre un suivi individuel des animaux, diverses technologies de capteurs ont été utilisées à des fins pratiques en ferme et au niveau de la recherche scientifique pour contrôler différentes variables physiques, induisant notamment l’émergence du domaine de l’élevage de précision. Plusieurs dispositifs ont été conçus, dont certains ont déjà été commercialisés, principalement pour la détection de paramètres relatifs au statut physiologique ou à la santé de l’animal, notamment la détection de la chaleur, des signes de la mise-bas ou des maladies telles de la boiterie et les mastites. Les comportements liés au pâturage peuvent être détectés avec des capteurs de pression, acoustiques (microphone), électromyographiques ou accélérométriques en classifiant la posture et les mouvements adoptés par les animaux lorsqu’ils expriment des comportements unitaires (pâturage, rumination, repos, marches, etc.) et des comportements plus fins tels que la mastication ou la bouchée en classifiant les mouvements de la mâchoire. En comparaison avec les observations réelles, les précisions de détection de ces comportements varient selon le type de capteur, sa position sur l’animal, la fréquence d’acquisition des données, la méthode d’analyse des données ainsi que la fenêtre de calcul y afférente. L’état de l’art a notamment montré la performance des accéléromètres pour la détection des comportements unitaires et des bouchées. Une centrale inertielle composée d’accéléromètre, de gyroscope et de capteur de localisation, a été utilisée pour enregistrer les mouvements et les postures des vaches en prairie avec une fréquence de 100Hz. Un algorithme booléen a été élaboré afin de détecter les comportements d’ingestion de fourrage et de rumination et une précision moyenne de 91% a été obtenue en utilisant une fenêtre de calcul d’une seconde lors de la validation de celui-ci. Une analyse approfondie des signaux accélérométriques a permis de détecter les mouvements de la mâchoire effectués lors du pâturage et de la rumination. Confrontées à différentes hauteurs de prairie, les vaches présentaient des fréquences de bouchée supérieures lorsque la hauteur est basse. Enfin, grâce à l’exploitation des données de localisation, il a été observé que le comportement de pâturage des vaches présentait des modèles similaires en termes de mouvement confirmant un mouvement de troupeau existant au sein d’un groupe de vaches présentes sur une même prairie. Cependant les vaches présentaient des stratégies différentes en termes d’occupation de l’espace selon qu’elles entrent dans une prairie à modalité haute ou basse. Le suivi continu des comportements des vaches en prairie utilisant des capteurs et conduisant à de telles localisations des bouchées, doit être combiné avec des données sur la distribution spatiale des plantes au niveau de la prairie, en termes d’espèce, de densité et de qualité, si possible avec les mêmes précisions, pour permettre de couvrir totalement le processus de pâturage et les stratégies des animaux quand ils sont confrontés à des environnements contrastés et de proposer des outils déterminants pour optimiser la gestion des prairies
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Cattle Grazing dynamics under contrasted pasture characteristics at temporal and spatial scales
Université de Liège Liège Belgique, 2017Co-Authors: Andriamandroso AndriamasinoroAbstract:audience: researcher, professional, student, popularizationGrassland constitutes an important and a low-cost food source for Grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, Grazing is a normal Behavior displayed in an attempt to eat the amount of forage to fulfill their nutritive requirements for maintenance and production. It is the most time-consumed activity of cows reared in pasture-based systems. With the increase of herd size, on one hand, farmers have been constrained to integrate innovative tools and techniques, such as milking robot, to improve the production system in particular to reduce the labor cost. On the other hand, such change might reduce time allocated for Grazing on pasture. However pasture-based systems constitute a real pillar for sustainability as they are socially acceptable and environmentally profitable as they play an important role on ecosystem services and biodiversity provision. Studying Grazing processes at individual level, which finally is the key point of animal-plant interactions, is a valuable research domain to enhance the knowledge about this mechanism and to feed decision support tools. This thesis aimed to link the changes in pasture characteristics to the Grazing Behavior of cattle in order to better understand the Grazing strategy under different pasture characteristics and forage allowances. To allow an individual monitoring, sensor technology has integrated within farms and livestock researches to monitor many physical variables, inducing the emergence of precision livestock farming approach. Different types of sensors were designed, and already commercialized for some, primarily for physiological status detections such as heat, parturition or diseases. Grazing Behaviors could be monitored using pressure, electromyography, acoustic or accelerometric sensors by classifying posture and movements of the animal into unitary Behaviors (Grazing, ruminating, resting, walking, etc.) and finer Behavior such as chews and bites through jaw movements’ detection. When compared to real observation, detection accuracies of these Behaviors were variable according to the type of sensor, its position on the animal during data acquisition on pasture, the data recording frequency, the time-window and the method dedicated to the post-recording data analysis. State-of-the-art analysis demonstrated a great performance of accelerometers for unitary Behaviors and bites detection. An inertial measurement unit, integrating accelerometer, gyroscope and location sensors, was used for recording cattle movements during Grazing at high sampling rate (100Hz). It allows a correct detection of grass intake and rumination Behaviors with an average accuracy of 91% using 1-second time-window when calibrating and validating the detection algorithm. Deeper analysis of accelerometric signal allowed us to detect bites and chews performed during Grazing and ruminating. Effects of pasture heights on Grazing bites characteristics were differentiated by a higher frequency when pasture is at a lower height. Finally when combined to geographical information, a similar pattern was observed for cattle Grazing on the same spot confirming their herd movement during Grazing in terms of bites location. Differences were visible under different pasture heights but not significant. Such bites location, combined with continuous monitoring of cattle Behaviors, through use of sensors, should be furtherly linked with more pasture characteristics, if possible with the same accuracy, and monitored on longer period in order to obtain a complete coverage of cattle Grazing strategy and the effect of contrasted environment in order to purpose valuable tool for a better Grazing management.La prairie constitue une importante ressource alimentaire, et à moindre coût, pour les ruminants. Une gestion optimale de cette ressource doit considérer à la fois la productivité du fourrage et les besoins des animaux. Pour les bovins, le pâturage est un comportement normal d’ingestion de fourrage dans le but de satisfaire leurs besoins nutritionnels d’entretien et de production. Il s’agit du comportement qui occupe le plus de temps parmi les activités journalières des bovins en prairie. Avec l’augmentation de la taille des troupeaux, d’une part, les éleveurs ont été contraints d’intégrer des pratiques innovantes, telles que le robot de traite, par exemple, pour améliorer le système de production et notamment pour diminuer le coût en main d’œuvre. D’autre part, de tels changements ont eu tendance à réduire le temps alloué au pâturage des animaux. Cependant les systèmes de production à base de pâturage sont actuellement perçus comme un pilier du développement durable. En effet, ils suscitent un regain d’intérêt au niveau de la société et surtout sont bénéfiques pour l’environnement sachant que la prairie joue un rôle important dans la fourniture de services écosystémiques et de biodiversité. Etudier le processus de pâturage à l’échelle de l’individu, qui est un point-clé dans l’interaction plante-animal, constitue un domaine de recherche d’intérêt pour approfondir les connaissances à propos de ce mécanisme et pour développer des outils d’aide à la décision. La présente thèse a pour but de déterminer les liens entre les changements des caractéristiques du pâturage et le comportement des bovins afin de mieux comprendre les stratégies adoptées par les vaches dans un environnement prairial contrasté. Pour permettre un suivi individuel des animaux, diverses technologies de capteurs ont été utilisées à des fins pratiques en ferme et au niveau de la recherche scientifique pour contrôler différentes variables physiques, induisant notamment l’émergence du domaine de l’élevage de précision. Plusieurs dispositifs ont été conçus, dont certains ont déjà été commercialisés, principalement pour la détection de paramètres relatifs au statut physiologique ou à la santé de l’animal, notamment la détection de la chaleur, des signes de la mise-bas ou des maladies telles de la boiterie et les mastites. Les comportements liés au pâturage peuvent être détectés avec des capteurs de pression, acoustiques (microphone), électromyographiques ou accélérométriques en classifiant la posture et les mouvements adoptés par les animaux lorsqu’ils expriment des comportements unitaires (pâturage, rumination, repos, marches, etc.) et des comportements plus fins tels que la mastication ou la bouchée en classifiant les mouvements de la mâchoire. En comparaison avec les observations réelles, les précisions de détection de ces comportements varient selon le type de capteur, sa position sur l’animal, la fréquence d’acquisition des données, la méthode d’analyse des données ainsi que la fenêtre de calcul y afférente. L’état de l’art a notamment montré la performance des accéléromètres pour la détection des comportements unitaires et des bouchées. Une centrale inertielle composée d’accéléromètre, de gyroscope et de capteur de localisation, a été utilisée pour enregistrer les mouvements et les postures des vaches en prairie avec une fréquence de 100Hz. Un algorithme booléen a été élaboré afin de détecter les comportements d’ingestion de fourrage et de rumination et une précision moyenne de 91% a été obtenue en utilisant une fenêtre de calcul d’une seconde lors de la validation de celui-ci. Une analyse approfondie des signaux accélérométriques a permis de détecter les mouvements de la mâchoire effectués lors du pâturage et de la rumination. Confrontées à différentes hauteurs de prairie, les vaches présentaient des fréquences de bouchée supérieures lorsque la hauteur est basse. Enfin, grâce à l’exploitation des données de localisation, il a été observé que le comportement de pâturage des vaches présentait des modèles similaires en termes de mouvement confirmant un mouvement de troupeau existant au sein d’un groupe de vaches présentes sur une même prairie. Cependant les vaches présentaient des stratégies différentes en termes d’occupation de l’espace selon qu’elles entrent dans une prairie à modalité haute ou basse. Le suivi continu des comportements des vaches en prairie utilisant des capteurs et conduisant à de telles localisations des bouchées, doit être combiné avec des données sur la distribution spatiale des plantes au niveau de la prairie, en termes d’espèce, de densité et de qualité, si possible avec les mêmes précisions, pour permettre de couvrir totalement le processus de pâturage et les stratégies des animaux quand ils sont confrontés à des environnements contrastés et de proposer des outils déterminants pour optimiser la gestion des prairies
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LINKING CATTLE Grazing Behavior TO METHANE AND CARBON DIOXIDE DYNAMICS
Universiteit Gent. Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen, 2016Co-Authors: Blaise Yannick, Lebeau Frédéric, Andriamandroso Andriamasinoro, Beckers Yves, Heinesch Bernard, Bindelle JérômeAbstract:audience: researcher, professional, studentVarious methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well as addressing the selection of low producing individuals. On pasture and in the barn, variations in CH4 emissions are observed depending on the time of the day. However, no studies have been made to link these diurnal fluctuations to behavioural phases, especially on pasture. The aim of this study was to understand the individual dynamics of CH4 production and their links to the Grazing behaviour. For this purpose, a new tool was specifically developed. Five red-pied dry cows were equipped with infrared CH4 and carbon dioxide (CO2) sensors measuring concentrations in the exhaled air at 4 Hz. The animals were equipped with a heart rate belt (HR) and motion sensors to detect their feeding behaviours (Grazing vs. rumination) for periods of 8 h/d. Wind speed (WS) was also monitor to verify interference with sampled gas concentrations. Results showed that using the CH4:CO2 ratio reduced the interference with WS that was observed on raw CH4 and CO2 concentration signals. CH4:CO2 ratio average over 5 min periods indicated that CH4 emissions were lower during Grazing than rumination (P
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LINKING CATTLE Grazing Behavior TO METHANE AND CARBON DIOXIDE DYNAMICS
2016Co-Authors: Blaise Yannick, Lebeau Frédéric, Andriamandroso Andriamasinoro, Beckers Yves, Heinesch Bernard, Bindelle JérômeAbstract:Various methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well as addressing the selection of low producing individuals. On pasture and in the barn, variations in CH4 emissions are observed depending on the time of the day. However, no studies have been made to link these diurnal fluctuations to behavioural phases, especially on pasture. The aim of this study was to understand the individual dynamics of CH4 production and their links to the Grazing behaviour. For this purpose, a new tool was specifically developed. Five red-pied dry cows were equipped with infrared CH4 and carbon dioxide (CO2) sensors measuring concentrations in the exhaled air at 4 Hz. The animals were equipped with a heart rate belt (HR) and motion sensors to detect their feeding behaviours (Grazing vs. rumination) for periods of 8 h/d. Wind speed (WS) was also monitor to verify interference with sampled gas concentrations. Results showed that using the CH4:CO2 ratio reduced the interference with WS that was observed on raw CH4 and CO2 concentration signals. CH4:CO2 ratio average over 5 min periods indicated that CH4 emissions were lower during Grazing than rumination (P
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High rate monitoring CH4 production dynamics and their link with Behavioral phases in cattle
2016Co-Authors: Blaise Yannick, Lebeau Frédéric, Andriamandroso Andriamasinoro, Beckers Yves, Heinesch Bernard, Bindelle JérômeAbstract:Microbial fermentation in the rumen produces methane (CH4) which is a loss of energy for ruminants and also contributes to global warming. While the respiration chamber is the standard reference for CH4 emissions quantification, daily CH4 production dynamics can be measured only by steps of 30 min and measurements on pasture are impossible. The alternative method using SF6 as tracer gas can be applied for Grazing animals but provides average CH4 production values over at least several hours, making it impossible to measure short term dynamics of rumen CH4 production with changing animal Behavior along the day. Newly developed methods using CO2 as internal tracer gas extrapolate CH4 emissions from few short measurements. However, both CO2 and CH4 emissions fluctuate during the day depending on the Behavior and the post-feeding times questioning the validity of this method. Therefore, an innovative device was developed to monitor at a high rate CH4 and CO2 emission dynamics in order to investigate the link between CH4 dynamics and the animal Behavior on pasture. Preliminary results showed the ability of the device to record differences in CH4:CO2 ratios and eructation frequencies according to the individual and the Behavior. Results from complementary experiments in barn with animals fed contrasting diets regarding CH4 production (with and without linseed) and on pasture with different forage allowance will be presented in order to highlight how post-feeding time and Grazing Behavior impact CO2 and CH4 emission dynamics along the day
