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Adaptations comportementales des vaches laitières aux contraintes d’abreuvement selon leur position sociale
No full textRecommendations exist to ensure that dairy herds do not suffer from prolonged thirst. However, the current evaluation criteria for on-farm watering systems, on which these recommendations are based, induces an obligation of means but not of results. This thesis has shown that rearing conditions observed on farms can affect animal drinking behavior, with heterogeneous responses between animals. During this work, a method was sought to automatically characterize the social hierarchy established at drinking troughs. Experiments were then conducted to simulate a variety of on-farm housing conditions, with constraints on watering. The results suggest that current recommendations regarding the number of animals per trough still guarantee the absence of prolonged thirst.On the other hand, the most subordinate animals in the herd seemed to find it more difficult to adapt to constraints such as an increase in the density of animals at water troughs or temporal restrictions on access to water. These temporal constraints also affected the resting time of the cows. Although all the cows managed to drink sufficiently, these results suggest that these constraints could affect their well-being. Finally, the experiments showed that certain parameters of drinking behavior, such as drinking rates or the distributions of watering into drinking bouts, could be used in future to develop new indicators to better characterize the absence of prolonged thirst in all cows in dairy herds.Il existe des recommandations pour garantir l'absence de soif dans les troupeaux. Cependant, les critères d'évaluation des équipements d'abreuvement sur lesquels reposent ces recommandations répondent à des obligations de moyens mais pas de résultats. Cette thèse a montré comment des conditions d'élevage variées, observables dans les fermes, peuvent affecter l'abreuvement des animaux et refléter leur hétérogénéité de réponse face à certaines situations. La recherche d'une méthode d'identification automatique de la hiérarchie social qui s'établit aux abreuvoirs a été menée. Puis, des expérimentations simulant des conditions d'élevage variées visibles en ferme, avec des contraintes sur l'abreuvement, ont été mises en œuvre. Les résultats suggèrent que les recommandations actuelles en matière de nombre d'animaux par abreuvoir garantissent toujours l'absence de soif prolongée. En revanche, les animaux les plus subordonnés des troupeaux semblent avoir plus de mal à s'adapter à des contraintes telles que des augmentations de la densité d'animaux aux abreuvoirs ou des restrictions temporelles d'accès à l'eau. Ces contraintes temporelles ont également affecté le temps de repos des vaches. Ainsi, bien que toutes les vaches aient réussi à s'abreuver de manière suffisante, ces résultats suggèrent que ces contraintes pourraient affecter leur bien-être. Les expérimentations menées ont enfin mis en évidence que certains comportements liés à l'abreuvement, tels que la vitesse d'abreuvement ou les épisodes de buvées, pourraient, à l’avenir, servir de base pour créer de nouveaux indicateurs, afin de mieux caractériser l'absence de soif prolongée pour toutes les vaches des troupeaux laitiers
Dairy cows' behavioral adaptations to watering restrictions as a function of their social position
No full textIl existe des recommandations pour garantir l'absence de soif dans les troupeaux. Cependant, les critères d'évaluation des équipements d'abreuvement sur lesquels reposent ces recommandations répondent à des obligations de moyens mais pas de résultats. Cette thèse a montré comment des conditions d'élevage variées, observables dans les fermes, peuvent affecter l'abreuvement des animaux et refléter leur hétérogénéité de réponse face à certaines situations. La recherche d'une méthode d'identification automatique de la hiérarchie social qui s'établit aux abreuvoirs a été menée. Puis, des expérimentations simulant des conditions d'élevage variées visibles en ferme, avec des contraintes sur l'abreuvement, ont été mises en œuvre. Les résultats suggèrent que les recommandations actuelles en matière de nombre d'animaux par abreuvoir garantissent toujours l'absence de soif prolongée. En revanche, les animaux les plus subordonnés des troupeaux semblent avoir plus de mal à s'adapter à des contraintes telles que des augmentations de la densité d'animaux aux abreuvoirs ou des restrictions temporelles d'accès à l'eau. Ces contraintes temporelles ont également affecté le temps de repos des vaches. Ainsi, bien que toutes les vaches aient réussi à s'abreuver de manière suffisante, ces résultats suggèrent que ces contraintes pourraient affecter leur bien-être. Les expérimentations menées ont enfin mis en évidence que certains comportements liés à l'abreuvement, tels que la vitesse d'abreuvement ou les épisodes de buvées, pourraient, à l’avenir, servir de base pour créer de nouveaux indicateurs, afin de mieux caractériser l'absence de soif prolongée pour toutes les vaches des troupeaux laitiers.Recommendations exist to ensure that dairy herds do not suffer from prolonged thirst. However, the current evaluation criteria for on-farm watering systems, on which these recommendations are based, induces an obligation of means but not of results. This thesis has shown that rearing conditions observed on farms can affect animal drinking behavior, with heterogeneous responses between animals. During this work, a method was sought to automatically characterize the social hierarchy established at drinking troughs. Experiments were then conducted to simulate a variety of on-farm housing conditions, with constraints on watering. The results suggest that current recommendations regarding the number of animals per trough still guarantee the absence of prolonged thirst.On the other hand, the most subordinate animals in the herd seemed to find it more difficult to adapt to constraints such as an increase in the density of animals at water troughs or temporal restrictions on access to water. These temporal constraints also affected the resting time of the cows. Although all the cows managed to drink sufficiently, these results suggest that these constraints could affect their well-being. Finally, the experiments showed that certain parameters of drinking behavior, such as drinking rates or the distributions of watering into drinking bouts, could be used in future to develop new indicators to better characterize the absence of prolonged thirst in all cows in dairy herds
Adaptations comportementales des vaches laitières aux contraintes d’abreuvement selon leur position sociale
No full textRecommendations exist to ensure that dairy herds do not suffer from prolonged thirst. However, the current evaluation criteria for on-farm watering systems, on which these recommendations are based, induces an obligation of means but not of results. This thesis has shown that rearing conditions observed on farms can affect animal drinking behavior, with heterogeneous responses between animals. During this work, a method was sought to automatically characterize the social hierarchy established at drinking troughs. Experiments were then conducted to simulate a variety of on-farm housing conditions, with constraints on watering. The results suggest that current recommendations regarding the number of animals per trough still guarantee the absence of prolonged thirst.On the other hand, the most subordinate animals in the herd seemed to find it more difficult to adapt to constraints such as an increase in the density of animals at water troughs or temporal restrictions on access to water. These temporal constraints also affected the resting time of the cows. Although all the cows managed to drink sufficiently, these results suggest that these constraints could affect their well-being. Finally, the experiments showed that certain parameters of drinking behavior, such as drinking rates or the distributions of watering into drinking bouts, could be used in future to develop new indicators to better characterize the absence of prolonged thirst in all cows in dairy herds.Il existe des recommandations pour garantir l'absence de soif dans les troupeaux. Cependant, les critères d'évaluation des équipements d'abreuvement sur lesquels reposent ces recommandations répondent à des obligations de moyens mais pas de résultats. Cette thèse a montré comment des conditions d'élevage variées, observables dans les fermes, peuvent affecter l'abreuvement des animaux et refléter leur hétérogénéité de réponse face à certaines situations. La recherche d'une méthode d'identification automatique de la hiérarchie social qui s'établit aux abreuvoirs a été menée. Puis, des expérimentations simulant des conditions d'élevage variées visibles en ferme, avec des contraintes sur l'abreuvement, ont été mises en œuvre. Les résultats suggèrent que les recommandations actuelles en matière de nombre d'animaux par abreuvoir garantissent toujours l'absence de soif prolongée. En revanche, les animaux les plus subordonnés des troupeaux semblent avoir plus de mal à s'adapter à des contraintes telles que des augmentations de la densité d'animaux aux abreuvoirs ou des restrictions temporelles d'accès à l'eau. Ces contraintes temporelles ont également affecté le temps de repos des vaches. Ainsi, bien que toutes les vaches aient réussi à s'abreuver de manière suffisante, ces résultats suggèrent que ces contraintes pourraient affecter leur bien-être. Les expérimentations menées ont enfin mis en évidence que certains comportements liés à l'abreuvement, tels que la vitesse d'abreuvement ou les épisodes de buvées, pourraient, à l’avenir, servir de base pour créer de nouveaux indicateurs, afin de mieux caractériser l'absence de soif prolongée pour toutes les vaches des troupeaux laitiers
Détection de problèmes techniques à partir de données individuelles d’abreuvement de truies gestantes
No full textInternational audienceBesides farmer observations, new technology such as connected troughs allows for individual and automatic monitoring of gestating sows. The aim of this study was to determine whether technical malfunctioning in the gestation room can be detected from records of individual water intake. Data were collected for 52 gestating sows during two types of induced stress events: thermic stress (hot and cold) and feeding stress, due to the closing of an automatic feeder. Data were analyzed using a smoothing method in R software (“fda” package) that can smooth data to varying degrees to detect potential disruptions. A specificity/sensitivity analysis was then conducted. Initial results showed that gestating sows drank a mean of 8.8 L of water/d, at a frequency of 14.5 visits/d and for a global duration of 9.5 min/d. One to four perturbations per gestation were detected by the smoothing methods. The specificity analyses highlighted that the event-detection method was more than 95% specific and thus able to detect nearly all true negative individuals. But the sensitivity was very low (9.4%). In conclusion, too few technical malfunctions can be detected from records of individual water intake. The method needs to be more accurate; one solution could be to apply it simultaneously to more variables
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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