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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Neuroendocrine Profiles of Pekin Ducks Associated with Positive and Negative Affective States

Melanie M Bergman (19206493), Gregory S. Fraley (15440574), J. Alex Pasternak (13886678), Karen Schwean-Lardner (6678449), Darrin Karcher (5497484) 27 July 2024 (has links)
<p dir="ltr">The Pekin duck, a major poultry product, is an important livestock species that requires further study to understand their physiological needs and welfare. Welfare improvements can be obtainable by measuring a duck’s response to its environment and developing management practices that allow ducks to explore positive natural behaviors and minimize negative affective states. Assessing welfare includes measuring physical and mental states of an animal and how it copes with its environment. This thesis sets out to use established indicators for mental state, such as serotonin (5-HT) and dopamine (DA), to validate methods of measuring duck affective state applied to environment changes. Affective states can be assessed using neurotransmitter concentrations inserted into turnover equations to understand serotonergic and dopaminergic activity within the synapse. Similarly, gene expression can be linked to affective state by investigating the rate-limiting enzyme in 5-HT and DA synthesis. Developing neuroendocrine profiles for the Pekin duck can elucidate how environmental changes affect physiology and welfare. </p><p dir="ltr">Preening cups are a semi open water source placed within duck barns to improve welfare and allow for positive natural behaviors. Since ducks are waterfowl, many believe these birds need access to open water to develop naturally and have positive welfare. Our lab designed an experiment, referenced in Chapter 3, to compare ducks raised with preening cups to ducks raised with only water nipple lines. At Purdue Animal Science Research and Education Center (ASREC), 260 grow-out Pekin ducks were raised to the industry standard. There were 2 pens that had access to preening cups on day 18 and 2 pens had access to only nipple lines. We collected duck brains on day 18 before preening cup placement (PRE, n = 6). On day 43, we collected duck brains from pens with preening cups (PC, n = 6) and from pens without preening cups (CON, n = 6). Then, brains were hemisected and further dissected into caudal mesencephalon (CM), rostral mesencephalon (RM), diencephalon (DI), and forebrain (FB). The right portions of each brain were used to investigate neurotransmitter concentrations and turnover using mass spectrometry. While the left portions were used to investigate gene expression of tryptophan hydroxylase (TPH1, TPH2) and tyrosine hydroxylase (TH). Our results found no significant differences in 5-HT turnover or 5-HT static levels associated with preening cups across collection days. In the CM, we found a decrease in DA turnovers for PC and CON (p = 0.0067) when compared to PRE. Also, we found a decrease in DA turnover for PC when compared to PRE and CON (p = 0.003) in the RM. In the CM, we found increases in TPH1 expression (p = 0.022) for PC and CON when compared to PRE and in TH expression (p = 0.022) for CON when compared to PRE. There were no significant differences found in the RM and DI brain areas for gene expression. In the FB, we found a decrease in TH gene expression (p = 0.031). Overall, our data highlights an increase in dopaminergic activity within the midbrain. This increase in DA can be correlated with aggressive behavior witnessed from ducks housed with preening cups. Elevated DA is associated with addiction and resource guarding. In this experimental study, we concluded that preening cups placed with a small number of ducks (n = 65 ducks per preening cup) may elicit aggressive behavior and decrease welfare. </p><p dir="ltr">The results of this initial study led us to the question of how a duck affective state is altered by preening cups in a large commercial setting. A commercial Pekin duck barn will place one preening cup for approximately 1,000-1,500 ducks, which means a barn will carry about 3-5 preening cups. Similar methodology was used in Chapter 4 to investigate the ducks affective state using mass spectrometry and qRT-PCR to assess 5-HT and DA activity within the brain. We visited four commercial duck barns with an average of 7,500 ducks on day (d)21 prior to preening cup placement, d28 one week after preening cup placement, and d35 one day prior to processing. We collected litter samples to test moisture content (n = 3/barn/day) and found no differences before or after preening cup placement. We performed a transect walk by moving systematically through each barn and recording the frequency of welfare concerns. All barns showed low percentages of welfare concerns while differences were likely due to natural aging of ducks in a production system. Brains were collected from two locations in the barn including ducks actively using the preening cup (PC) and ducks across the barn not actively performing any behaviors other than standing or sitting (CON). Brains were divided into CM, RM, and DI brain areas and each half was assessed with 5-HT and DA turnover along with TPH1, TPH2, and TH gene expression. No differences were found for 5-HT turnover or static levels. This suggests that preening cups are not altering affective state. DA turnover was decreased in the CM (p < 0.05) and DI (p < 0.001) due to age, but no differences were found between collection location (PC vs CON). We link this increase in dopaminergic activity to natural aging and preparation for puberty as no aggressive behavior was witnessed in commercial barns. Aggression and resource guarding of commercial preening cups is unlikely due to the increased number of ducks per water source and the large space the ducks can access. There was increased TPH1 expression within the RM brain area for d35 ducks when compared to d28 and d21. We conclude that affective state is not variable within the barn based on collection locations. Overall, 5-HT was not affected by preening cups and DA was affected by age. This means that preening cups may not improve affective state and welfare, but they also do not cause determinantal effects either. </p><p dir="ltr">Another major welfare concern associated with environment is transportation for Pekin ducks. To assess how affective state is altered by crating and transportation of hens and drakes, Chapter 5 used similar methodology as the previous studies. Transportation may cause an acutely stressful event while activating a physiological stress response. Chapter 5 measured several central and peripheral physiological parameters to assess responses to transportation. Thirty-six, 23-week-old breeder ducks from a commercial facility were randomly assigned to one of three treatment groups. The control group (CON) was caught and immediate euthanized in the pen, the crate group (CRA) was caught and crated for 90 minutes before euthanasia, and the transport group (TRA) was caught, crated, and loaded into the back of a truck to be driven on country roads at 55 mph for 90 minutes before immediate euthanasia. Blood was collected for corticosterone ELISA analysis and blood smear heterophil to lymphocyte ratio (HLR) analysis. We found that hens showed an increase in HLR (p = 0.035) and serum corticosterone (p = 0.01) due to CRA. Drakes and hens showed an increase in HLR (p = 0.035) and serum corticosterone (p = 0.0084) for TRA. These results suggest that transportation is a stressor that elicits a sex dependent response where hens increase corticosterone and HLR under CRA unlike drakes who only showed a stress response under TRA. Likewise, a sex difference was shown for 5-HT turnover where hens show a stepwise increase from CON to CRA (p = 0.01) and from CRA to TRA (p = 0.016) in the CM and RM. There were no differences for DA turnover while TPH1 gene expression was decreased (p = 0.03) for TRA hens when compared to CON and CRA hens. Our results suggest that transportation negatively shifts affective state by increasing stress responses in ducks and reducing serotonergic activity in hens. In the future, care should be taken to evaluate stress between sexes and minimize transportation time. </p><p dir="ltr">In conclusion, preening cups and transportation are important aspects of a Pekin ducks’ life that alter affective state and physiology. We recommend proper management of preening cups to ensure positive welfare by placing water sources over open pits to prevent excess accumulation of water in the barn. We recommend that while evaluating stressors, researchers need to assess different sexes and collection time from the onset of the stressor. Future studies can include determining affective state for other enrichments such as environmental enrichment devices or investigating commercial barns without preening cups during the production cycle. Continued research could measure affective state following shorter transportation stress or chronic stress to resolve what timeframes alter 5-HT and DA turnover. Transportation may be minimized by installing on-site processing facilities to stun and process animals without transportation to reduce negative affective states. In an academic setting, pharmaceutical intervention may be interesting to investigate to improve affective state during stressful events.</p>
2

Multimodal e-learning : an empirical study

Faneer, Musa Khalifa A. January 2015 (has links)
This empirical work aims to investigate the impact of using multimodal communication metaphors on e-learning systems’ usability, overall user experience and affective state. The study proposed a triple evaluation approach to avoid the problem of conventional assessment relying only on usability measurements of efficiency, effectiveness and user satisfactions. Usability in that sense refers only to the functionality and pragmatic side of the product and neglects other aspects of the system. Learning is a cognitive and repetitive task, requiring learners’ attention as well as their interest. Therefore, when delivering content, in addition to the pragmatic functionality, an e-learning system should provide a constructive overall user experience and positive affective state. Doing so will ensure user engagement, facilitate the learning process and increase learners’ performance. The impact of using five different communication metaphors was evaluated in three dimensions using the proposed approach. Within the usability dimension, the evaluation criteria involved measuring system efficiency, effectiveness, user satisfaction and learning performance. Within the user experience dimension, the evaluation criteria involved measuring pragmatic aspects of the user experience, the hedonic aspects of user experience in terms of stimulation as well as identification and the overall system attractiveness. Within the affective state dimension a self-assessments manikin technique was used in conjunction with biofeedback measurements, and users’ valence, arousal and dominance were measured. The study found that system attractiveness and the hedonic user experience had a profound impact on users’ learning performance and attitude toward the tested system. Furthermore, they influenced users’ views and judgement of the system and its usability. The communication metaphors were not equal in their influence within the evaluation criteria. Empirically derived guidelines were produced for the use and integration of these metaphors in e-learning systems. The outcome of the study highlights the need to use the triple evaluation approach in the assessment of e-learning interfaces prior to their release for better adoption and acceptance by end users.
3

The Effects of Performance Feedback on Exercise, Physiological Reactivity, and Affective State among Hostile College Students

Lin, Crystal Chia-Sheng 01 May 2002 (has links)
hostility has been found to be a risk factor for cardiovascular disease. One proposed pathway between hostility and cardiovascular disease is an increase in cardiovascular reactivity among hostile individuals when faced with challenging, competitive situations, in which interpersonal stressors are present. A potential situation that may elicit this exaggerated reactivity is found in cardiac rehabilitation exercise programs. Such factors may be competition and feedback regarding their performance. This study sought to find out how hostile individuals would respond physiologically, behaviorally, and affectively when presented with negative and positive performance feedback, while exercising in a challenging, competitive setting. It was found that the three groups (positive feedback, negative feedback, no feedback) did not differ on physiological reactivity, exercise behavior, or affect as a result of the type of feedback they received. Limitations of the study are discussed and improvements for future studies are suggested.
4

Ensino de algoritmos : detecção do estado afetivo de frustração para apoio ao processo de aprendizagem

Iepsen, Edécio Fernando January 2013 (has links)
Esta tese apresenta uma pesquisa para detectar os alunos que evidenciam sinais de frustração em atividades de ensino e de aprendizagem na área de Algoritmos, para então, auxiliá-los com ações proativas de apoio. A motivação para o desenvolvimento deste trabalho advém da dificuldade dos alunos na aprendizagem dos conceitos e técnicas de construção de Algoritmos, que se constitui num dos principais fatores que levam os cursos de formação em Computação a atingir altas taxas de evasão. Na busca por diminuir tal evasão, esta pesquisa destaca a importância de considerar os estados afetivos dos alunos, procurando motivá-los a estudar e resolver suas dificuldades de entendimento da resolução de problemas usando como suporte os sistemas computacionais. Para fins de validação da pesquisa foi construída uma ferramenta para: a) inferir o estado afetivo de frustração do aluno durante a resolução dos exercícios de Algoritmos, b) ao detectar sinais associados à frustração, apresentar recursos de apoio ao aprendizado do aluno. A inferência da frustração ocorre a partir da análise das variáveis comportamentais produzidas pelas interações dos alunos com a ferramenta. O apoio consiste na exibição de um tutorial com a resolução passo a passo do exercício no qual o aluno apresenta dificuldades e na recomendação de um novo exercício com níveis de complexidade mais lineares aos conceitos trabalhados até aquele ponto da disciplina. A partir destas ações, pretende-se auxiliar a fazer com que a frustração do aluno possa ser transformada em uma oportunidade de aprendizado. Estudos de Caso foram realizados com alunos de Algoritmos do curso de Tecnologia em Análise e Desenvolvimento de Sistemas da Faculdade de Tecnologia Senac Pelotas durante os anos de 2011 e 2012. Para identificar os padrões de comportamento dos alunos foram utilizadas técnicas de Mineração de Dados. Os resultados dos experimentos demonstraram que evidências como, o alto número de tentativas de compilação de um programa sem sucesso, o grande número de erros em um mesmo programa ou a quantidade de tempo gasto na tentativa de resolver um algoritmo, podem estar relacionadas ao estado de frustração do aluno. Além disso, em um dos experimentos foi realizado um comparativo de pré e pós-teste que demonstrou importantes avanços no aprendizado dos alunos participantes da pesquisa. / This thesis presents a research work on the detection of students who show signs of frustration in learning activities in the area of algorithms, to then assist them with proactive support actions. Our motivation for the development of this work comes from students' difficulty in learning the concepts and techniques for building algorithms, which constitutes one of the main factors for the high dropout rates of computing courses. With the intent of giving a contribution to the reduction of such evasion, this research highlights the importance of considering students' affective states, trying to motivate them to study and work out their difficulties, with the assistance of computer systems. For research validation purposes, a tool was built to: a) infer the student’s affective state of frustration while solving exercises of algorithms; b) detect signs associated with frustration, to provide resources to support student learning. The inference of frustration comes from the analysis of behavioral variables produced by the interactions of students with the tool. The support consists in displaying a tutorial with a step by step solution for the exercise in which the student shows difficulties, and the recommendation of a new exercise with more linear levels of complexity than the concepts worked until that point in the course. With these actions, our intention is to turn student's frustration into a learning opportunity. Case studies were conducted with students of Algorithms at the Faculty of Technology Senac Pelotas, in 2011 and 2012. Data mining techniques were used to identify patterns of student behavior. The experiment results showed that evidence such as the high number of attempts to compile a program without success, the large number of errors in a program or even the amount of time spent trying to solve an algorithm, might be related to the student’s frustration state. Additionally, a pre and post-test comparison showed significant progress in students' learning.
5

Ensino de algoritmos : detecção do estado afetivo de frustração para apoio ao processo de aprendizagem

Iepsen, Edécio Fernando January 2013 (has links)
Esta tese apresenta uma pesquisa para detectar os alunos que evidenciam sinais de frustração em atividades de ensino e de aprendizagem na área de Algoritmos, para então, auxiliá-los com ações proativas de apoio. A motivação para o desenvolvimento deste trabalho advém da dificuldade dos alunos na aprendizagem dos conceitos e técnicas de construção de Algoritmos, que se constitui num dos principais fatores que levam os cursos de formação em Computação a atingir altas taxas de evasão. Na busca por diminuir tal evasão, esta pesquisa destaca a importância de considerar os estados afetivos dos alunos, procurando motivá-los a estudar e resolver suas dificuldades de entendimento da resolução de problemas usando como suporte os sistemas computacionais. Para fins de validação da pesquisa foi construída uma ferramenta para: a) inferir o estado afetivo de frustração do aluno durante a resolução dos exercícios de Algoritmos, b) ao detectar sinais associados à frustração, apresentar recursos de apoio ao aprendizado do aluno. A inferência da frustração ocorre a partir da análise das variáveis comportamentais produzidas pelas interações dos alunos com a ferramenta. O apoio consiste na exibição de um tutorial com a resolução passo a passo do exercício no qual o aluno apresenta dificuldades e na recomendação de um novo exercício com níveis de complexidade mais lineares aos conceitos trabalhados até aquele ponto da disciplina. A partir destas ações, pretende-se auxiliar a fazer com que a frustração do aluno possa ser transformada em uma oportunidade de aprendizado. Estudos de Caso foram realizados com alunos de Algoritmos do curso de Tecnologia em Análise e Desenvolvimento de Sistemas da Faculdade de Tecnologia Senac Pelotas durante os anos de 2011 e 2012. Para identificar os padrões de comportamento dos alunos foram utilizadas técnicas de Mineração de Dados. Os resultados dos experimentos demonstraram que evidências como, o alto número de tentativas de compilação de um programa sem sucesso, o grande número de erros em um mesmo programa ou a quantidade de tempo gasto na tentativa de resolver um algoritmo, podem estar relacionadas ao estado de frustração do aluno. Além disso, em um dos experimentos foi realizado um comparativo de pré e pós-teste que demonstrou importantes avanços no aprendizado dos alunos participantes da pesquisa. / This thesis presents a research work on the detection of students who show signs of frustration in learning activities in the area of algorithms, to then assist them with proactive support actions. Our motivation for the development of this work comes from students' difficulty in learning the concepts and techniques for building algorithms, which constitutes one of the main factors for the high dropout rates of computing courses. With the intent of giving a contribution to the reduction of such evasion, this research highlights the importance of considering students' affective states, trying to motivate them to study and work out their difficulties, with the assistance of computer systems. For research validation purposes, a tool was built to: a) infer the student’s affective state of frustration while solving exercises of algorithms; b) detect signs associated with frustration, to provide resources to support student learning. The inference of frustration comes from the analysis of behavioral variables produced by the interactions of students with the tool. The support consists in displaying a tutorial with a step by step solution for the exercise in which the student shows difficulties, and the recommendation of a new exercise with more linear levels of complexity than the concepts worked until that point in the course. With these actions, our intention is to turn student's frustration into a learning opportunity. Case studies were conducted with students of Algorithms at the Faculty of Technology Senac Pelotas, in 2011 and 2012. Data mining techniques were used to identify patterns of student behavior. The experiment results showed that evidence such as the high number of attempts to compile a program without success, the large number of errors in a program or even the amount of time spent trying to solve an algorithm, might be related to the student’s frustration state. Additionally, a pre and post-test comparison showed significant progress in students' learning.
6

Ensino de algoritmos : detecção do estado afetivo de frustração para apoio ao processo de aprendizagem

Iepsen, Edécio Fernando January 2013 (has links)
Esta tese apresenta uma pesquisa para detectar os alunos que evidenciam sinais de frustração em atividades de ensino e de aprendizagem na área de Algoritmos, para então, auxiliá-los com ações proativas de apoio. A motivação para o desenvolvimento deste trabalho advém da dificuldade dos alunos na aprendizagem dos conceitos e técnicas de construção de Algoritmos, que se constitui num dos principais fatores que levam os cursos de formação em Computação a atingir altas taxas de evasão. Na busca por diminuir tal evasão, esta pesquisa destaca a importância de considerar os estados afetivos dos alunos, procurando motivá-los a estudar e resolver suas dificuldades de entendimento da resolução de problemas usando como suporte os sistemas computacionais. Para fins de validação da pesquisa foi construída uma ferramenta para: a) inferir o estado afetivo de frustração do aluno durante a resolução dos exercícios de Algoritmos, b) ao detectar sinais associados à frustração, apresentar recursos de apoio ao aprendizado do aluno. A inferência da frustração ocorre a partir da análise das variáveis comportamentais produzidas pelas interações dos alunos com a ferramenta. O apoio consiste na exibição de um tutorial com a resolução passo a passo do exercício no qual o aluno apresenta dificuldades e na recomendação de um novo exercício com níveis de complexidade mais lineares aos conceitos trabalhados até aquele ponto da disciplina. A partir destas ações, pretende-se auxiliar a fazer com que a frustração do aluno possa ser transformada em uma oportunidade de aprendizado. Estudos de Caso foram realizados com alunos de Algoritmos do curso de Tecnologia em Análise e Desenvolvimento de Sistemas da Faculdade de Tecnologia Senac Pelotas durante os anos de 2011 e 2012. Para identificar os padrões de comportamento dos alunos foram utilizadas técnicas de Mineração de Dados. Os resultados dos experimentos demonstraram que evidências como, o alto número de tentativas de compilação de um programa sem sucesso, o grande número de erros em um mesmo programa ou a quantidade de tempo gasto na tentativa de resolver um algoritmo, podem estar relacionadas ao estado de frustração do aluno. Além disso, em um dos experimentos foi realizado um comparativo de pré e pós-teste que demonstrou importantes avanços no aprendizado dos alunos participantes da pesquisa. / This thesis presents a research work on the detection of students who show signs of frustration in learning activities in the area of algorithms, to then assist them with proactive support actions. Our motivation for the development of this work comes from students' difficulty in learning the concepts and techniques for building algorithms, which constitutes one of the main factors for the high dropout rates of computing courses. With the intent of giving a contribution to the reduction of such evasion, this research highlights the importance of considering students' affective states, trying to motivate them to study and work out their difficulties, with the assistance of computer systems. For research validation purposes, a tool was built to: a) infer the student’s affective state of frustration while solving exercises of algorithms; b) detect signs associated with frustration, to provide resources to support student learning. The inference of frustration comes from the analysis of behavioral variables produced by the interactions of students with the tool. The support consists in displaying a tutorial with a step by step solution for the exercise in which the student shows difficulties, and the recommendation of a new exercise with more linear levels of complexity than the concepts worked until that point in the course. With these actions, our intention is to turn student's frustration into a learning opportunity. Case studies were conducted with students of Algorithms at the Faculty of Technology Senac Pelotas, in 2011 and 2012. Data mining techniques were used to identify patterns of student behavior. The experiment results showed that evidence such as the high number of attempts to compile a program without success, the large number of errors in a program or even the amount of time spent trying to solve an algorithm, might be related to the student’s frustration state. Additionally, a pre and post-test comparison showed significant progress in students' learning.
7

Chicken or fish? Do environmental complexity and stocking density impact affective states of broiler chickens and rainbow trout?

Anderson, Mallory G. 30 September 2021 (has links)
In commercial settings, broiler chickens and rainbow trout are housed in barren environments under high stocking densities, due to an emphasis on production efficiency. These monotonous housing conditions do not provide broilers or trout with the ability to perform functional, highly-motivated behaviors and increase their susceptibility to excessive anxiety and fear, resulting in negative affective states and poor animal welfare. Affective state (or emotional state) is a cumulative product of short-term life experiences, ranging from positive to negative. Because affective states are largely influenced by environmental condition, determining animal affective state can provide useful information on how to improve housing conditions in order to ensure positive experiences and good animal welfare. Cognitive processes are closely associated with affective state; a "cognitive bias" occurs when affective state influences aspects of cognition, such as judgement and attention. Animals in positive affective states make optimistically-biased decisions during ambiguous situations, judging the situation as if it will produce a positive outcome, and show less bias towards a perceived threat, responding in a less anxious and calm manner. Animals in negative affective states make pessimistically-biased decisions during ambiguous situations, judging the situation as if it will result in a negative outcome. Additionally, animals in negative affective states will bias their attention towards a perceived threat rather than alternative stimuli, responding in an anxious manner. Therefore, judgement and attention bias tests can be used to determine animal affective states. In Chapter 3, a judgement bias test was used to determine affective state of broiler chickens housed in either complex (perches, dust bath, pecking stones, and rotating enrichment objects) or barren (no enrichment) environments under either high or low stocking densities. Broilers housed in complex environments responded more optimistically during the judgement bias test than broilers from barren environments, indicating the former were in a positive affective state. Stocking density did not impact their responses in the judgement bias test, indicating that affective states were not impacted by that treatment. In Chapter 4, an attention bias test was used to determine level of anxiety and a tonic immobility test was used to determine fear in order to investigate affective state of broilers housed in the same conditions as described for Chapter 3. Broilers housed in complex environments were less anxious during the attention bias test than broilers from barren environments, indicating environmental complexity reduced anxiety in broilers. Stocking density did not impact anxiety. Broilers from high stocking density environments had shorter tonic immobility durations than broilers from low stocking density environments, suggesting the former were less fearful. Environmental complexity did not impact fearfulness. In Chapter 5, a judgement bias test was used to determine affective state of rainbow trout housed in either complex (shelter structure and artificial plants) or barren (no enrichment) tanks under either low or high stocking densities. Trout housed in high stocking density tanks responded optimistically during the judgement bias test, indicating they were in a more positive affective state compared to trout housed in low stocking density tanks. Environmental complexity did not impact their responses in the judgement bias test, indicating no effect of enrichments on affective states was found. These results indicate a beneficial relationship of a complex environment on broiler chicken affective state, observed through an optimistic judgement bias and reduced attention bias (anxiety) towards a perceived threat. Thus, providing a complex housing environment for broilers can improve their welfare and result in a positive affective state. Rainbow trout reared at the tested high density resulted in a positive affective state, although complexity did not benefit their welfare. Our results contribute much needed information on stocking densities to ensure fish welfare. Overall, environmental complexity, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental complexity. / Master of Science / Conventional housing of broiler chickens and rainbow trout (both raised for meat) causes concern for their welfare and affective states. Environmental conditions can greatly impact animals' affective states–their long-term emotional state, ranging from positive to negative. In barren environments at high stocking densities, broiler chickens and rainbow trout are prevented from showing normal behaviors and these conditions can compromise their affective state and welfare. By 'asking' chickens and trout whether the glass is half full or half empty, we can determine level of optimism or pessimism, and level of anxiety or calmness, therefore gaining a better understanding of their affective states. This can be done using a judgement bias test and attention bias test, where animal responses (optimism and anxiety) are recorded during ambiguous situations (judgement) and threatening situations (attention). Animals in positive affective states judge ambiguous situations optimistically (glass half full) and pay little attention towards perceived threats, while animals in negative affective states judge the same ambiguous situations pessimistically (glass half empty) and pay more attention towards perceived threats. In Chapter 3, responses to ambiguous situations were used to determine the affective state of broiler chickens housed in either enriched (perches, dust bath, pecking stones, rotating toys) or barren environments at either high or low stocking densities. Broiler chickens housed in enriched environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state compared to broilers housed in barren environments. Stocking density did not impact their level of optimism. In Chapter 4, responses to a perceived threat were used to determine level of anxiety and a tonic immobility test was used to determine fear of broilers housed under the same conditions as in Chapter 3. Broilers housed in enriched environments paid less attention to a perceived threat than broilers housed in barren environments, indicating the former were less anxious (glass half full) and in a positive affective state. Fear was not impacted by the tested enrichments, but birds kept under higher stocking densities did show reduced fear compared to birds in low-density environments. In Chapter 5, rainbow trout were housed in either enriched (shelter structure and artificial plants) or barren tanks at either high or low stocking densities. Affective state was evaluated through their responses to ambiguous situations. Trout housed in high stocking density environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state than trout housed in low stocking density environments. The enrichments did not impact their responses during the test, suggesting they did not impact fish optimism. These results indicate that an enriched environment improves broiler affective state and welfare compared to conventional housing conditions, the tested densities did not impact their welfare. Although an enriched environment did not positively impact responses of trout during ambiguous situations, our results show that housing rainbow trout in large groups results in a positive affective state and improved welfare status compared to housing trout in small groups. Overall, environmental enrichment, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental enrichment.
8

Happy Chickens: Novel Physiological and Behavioral Measures of Cumulative Experience in Broilers and Laying Hens

Campbell, Andrew Michael 03 April 2023 (has links)
Conventional housing environments for broiler chickens and commercial laying hens are often barren, high-density environments with an emphasis on production efficiency. These housing conditions limit birds' ability to display species-specific behaviors, can negatively impact health, and may contribute to negative cumulative experience. Cumulative experience is the culmination of all positive and negative experienced during an animal's lifetime. However, cumulative experience is difficult to quantify, as no validated measures of cumulative experience exist. Additionally, existing measures of negative animal experience mostly rely on interpretations of animal behavior which can be subjective, time consuming, and difficult to interpret. Therefore, there is scientific need for objective measures that can detect cumulative experience in poultry. Secretory and plasma Immunoglobulin A (IgA), telomere length, feather corticosterone concentrations, and attention bias testing all seem to respond to positive and negative experiences in humans or other non-human animal species, indicating that they may be useful as measures for poultry. Therefore, the objective of this thesis was to determine if these novel measures could be used as indicators of cumulative experience in broiler chickens and laying hens. In chapter 3, secretory and plasma IgA concentrations were measured in broilers raised in either high-complexity or low-complexity environments under either high or low stocking density over three replicated experiments. Birds housed in highly complex environments showed higher concentrations of plasma IgA compared to birds housed in low-complexity environments at day 48 of age, indicating reduced chronic stress in the former. Additionally, day 48 secretory IgA concentrations were decreased in birds housed in high-density environments compared to birds housed in low density environments, indicating birds from high-density environments were more chronically stressed. In chapter 4, gonad and kidney telomere length was measured to determine cumulative experience in broilers raised in the same housing conditions and replicated experiments of chapter 3. Treatment did not impact gonad telomere length, in line with expectations as gonads contain stem cells which produce high concentrations of telomerase. Birds housed in high-complexity pens had longer kidney telomeres compared to birds in low-complexity pens, indicating high-complexity birds had more positive cumulative experience. Stocking density did not impact kidney telomere length. In chapter 5, attention bias, tonic immobility, plasma and secretory IgA concentrations, and feather corticosterone concentrations were determined in laying hens raised in conventional cages or enriched floor pens. Birds in enriched floor pens showed increased attention bias, decreased tonic immobility, increased secretory IgA concentrations at week 22 of age, and decreased feather corticosterone concentrations compared to caged hens. These results indicate that compared to conventional cages, enriched pens in this study improved immune systems, reduced chronic stress, reduced fear, but increased anxiety in hens. In conclusion, secretory and plasma IgA and telomere length show appropriate contrast in response to broiler chicken housing conditions. However, additional work needs to be done before these measures can be widely used as measures of cumulative experience in poultry. Furthermore, attention bias, secretory IgA, and feather corticosterone showed an appropriate contrast between chronic stress responses in laying hens, but confirmation is needed in other contexts. Overall, the results indicate a beneficial relationship between environmental complexity and poultry welfare physiology and affective state, with the exception for anxiety in laying hens. Thus, providing an enriched environment can improve the welfare of commercial poultry and result in positive cumulative experience in most situations. Additionally, these results indicate that stocking density is a negative environment in broilers but potentially less intense than previously thought under experimental conditions. The assessment of behavioral and physiological measures of cumulative and positive animal experience should be included in experiments seeking to determine the impacts of environmental or management conditions to determine the broader impacts on poultry welfare. / Doctor of Philosophy / Conventional housing systems of broiler chickens (raised for meat) and laying hens (raised for egg production) can negatively impact their welfare. Animal welfare, defined as an animal's ability to interact with and cope with their environment, is an individual experience for each animal and fluctuates on a scale from very negative to very positive. Traditionally, measurements of animal welfare have focused only on avoiding the negative aspects of animal welfare such as fear, distress (negative stress), hunger, thirst, pain, and suffering. However, it is important that animals are provided opportunities to experience positive animal welfare to provide a life worth living. So, when measuring animal welfare, all positive and negative experiences (termed cumulative experience) should be included to form an accurate picture of an animal's welfare. However, no validated measures of cumulative experience exist in non-human animals. However, recently, several potential measures of cumulative experience have been proposed in human and non-human animals including secretory and plasma IgA, telomere length, feather corticosterone, and attention bias testing. So, the objective of this thesis was to determine if these proposed measures can be used to determine cumulative experience in commercial broilers and laying hens. In chapters 3 and 4, we investigated if secretory and plasma IgA concentrations (measure of chronic stress; chapter 3) and telomere length (measure of cumulative experience; chapter 4) responded to environmental complexity (positive stimulus) and stocking density (negative stimulus) over three replicated experiments. Broilers were housed in a 2 × 2 factorial study of either high or low complexity or high or low density. This resulted in four treatment groups of high-complexity/high-density, low-complexity/low-density, high-complexity/low-density, and low-complexity/high-density. During chapter 3, environmental complexity increased concentrations of plasma IgA, indicating that birds from high-complexity pens were under less chronic stress compared to birds from low-complexity pens. Alternatively, high density decreased secretory IgA, indicating that birds from high-density pens were under a more chronic stress than birds from low density pens. In chapter 4, environmental complexity increased telomere length in broilers compared to low-complexity pens indicating that environmental complexity positively impacted cumulative experience. However, stocking density did not impact telomere length, indicating that high density did not negatively impact cumulative experience. In chapter 5, we investigated if attention bias (measure of anxiety), tonic immobility duration (measure of fear), plasma and secretory IgA (chronic stress), and feather corticosterone (chronic stress) responded to environmentally enriched floor pens (positive housing system) and conventional caging (negative housing system). We found that birds housed in enriched floor pens were more anxious (increased attention bias), less fearful (decreased tonic immobility duration), and less chronically stressed (increased SIgA concentrations at week 22 and increased feather corticosterone concentrations) compared to birds housed in conventional cages. Overall, IgA concentrations and telomere length (broilers) and attention bias, secretory IgA concentration, and feather corticosterone concentrations (layers) seem useable as measures of animal experience in commercial poultry. Additionally, these results indicate that positive experience has a positive impact on cumulative experience in commercial poultry. Stocking density also seems to contribute to chronic stress in broilers, indicated by decreased SIgA concentrations, but only during the last few weeks of life. These findings should be confirmed by additional studies before common use as measures of cumulative experience in animals. However, the inclusion of measures of cumulative and positive animal experience should be included in experiment which wish to determine the broad impacts of housing system on non-human animals.
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Accumulation d'émotions et modifications de la sensibilité émotionnelle et des fonctions cognitives chez les ovins / Accumulation of emotions and modification of emotional reactivity and cognitive functions in sheep

Destrez, Alexandra 21 September 2012 (has links)
La question du bien-être de l’animal ne se pose que si on lui reconnaît le statut d’être sensible, capable de ressentir des émotions. Les émotions dépendent de processus cognitifs qu’entreprend l’animal pour évaluer son environnement. Pour comprendre le passage des émotions à un état de bien-être, nous avons étudié si ces processus cognitifs peuvent être biaisés par les émotions, lesquelles en retour seraient modulées durablement. Un modèle de stress chronique a été développé sur ovins : des agnelles sont exposées de manière répétée à des évènements aversifs, imprévisibles et incontrôlables. L’altération des systèmes neuroendocriniens et la potentialisation de la réactivité émotionnelle confirment que les agnelles ont développé un stress. Ensuite, l’effet de ce stress chronique sur les processus d’évaluation a été exploré : les agnelles stressées montrent une évaluation négative et des déficits d’apprentissage. Enfin, nous avons cherché à savoir si l’induction répétée d’émotions positives chez des agnelles stressées peut contrecarrer les biais d’évaluation négative induits par le stress. Elles évaluent de manière plus positive les événements ambigus que les agnelles uniquement stressées. L’accumulation d’émotions négatives peut conduire l’animal à développer une perception pessimiste de son environnement et une anhédonie, qui contribuent à auto-entretenir l’état de stress. La réduction d’anhédonie après induction répétée d’émotions positives montre que des stratégies cognitivo-comportementales sont envisageables pour corriger un stress. Bien qu’analytiques, ces travaux contribuent à la conception de pratiques d’élevage innovantes améliorant la qualité de vie des animaux. / The term ‘animal welfare’ embraces both physical and mental well-being of animals. The consideration of mental well-being of animals results from the acceptance that they are sentient beings that feel emotions. Emotions depend on cognitive abilities used by animals to evaluate its environment. To understand the progression from emotions to welfare state, we investigated whether these cognitive abilities could be biased by emotions which would be in turn modified in a lasting fashion. A model of chronic stress was developed in sheep : female lambs were repeatedly exposed to unpredictable and uncontrollable aversive events. The alteration of neuroendocrine systems and the increase of emotional reactivity showed that lambs underwent a chronic stress experience. Then, we investigated the impact of chronic stress on cognitive abilities : chronic stressed lambs showed negative evaluation and learning deficits. Finally, we investigated if a repeated exposure to positive emotions could alleviate negative cognitive biases in chronically stressed lambs. These animals showed a more positive evaluation of ambiguous events than lambs which had only been chronically stressed. Accumulation of negative emotions could lead the animal to develop a pessimistic-like perception of environment and anhedonia thus reinforcing and maintaining the state of stress. A decrease in anhedonia after repeated exposure to positive emotions in stressed animals showed that cognitive-behavioral strategies are possible to alleviate negative effects of stress. This work will contribute to develop innovating rearing practices which improve animal welfare.
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Promoção do Interesse em Criança com Autismo a partir de uma Plataforma Educacional Assistiva com Fantoche Eletrônico

Lima, Roceli Pereira January 2017 (has links)
A tecnologia, na sua evolução e transformação, influencia novos desdobramentos da técnica, dos processos e de aplicações, não somente na indústria, mas, também, em processos sociais e culturais. Salienta-se o uso de Tecnologia de Informação e Comunicação na Educação, Engenharia e de modelos da Computação Afetiva como recurso de ação mediadora para promoção do ser humano social. Neste contexto, a presente Tese desenvolveu, à luz da Teoria Sócio-Histórica, uma Plataforma Educacional Assistiva capaz de possibilitar a promoção do estado afetivo de interesse em crianças com Transtorno do Espectro Autista (TEA) dos anos iniciais do Ensino Fundamental. O TEA leva a uma condição de déficit no desenvolvimento, em escala de manifestação, nos domínios comportamental, comunicativo e ou cognitivo. O déficit de “atenção conjunta”, de reciprocidade emocional, de interesse, e prejuízo qualitativo na comunicação verbal e não verbal são características mencionadas largamente na literatura. Para “compensar” esse gap, o professor (assim como pais e terapeutas) precisa enfrentar o desafio de projetar estratégias de interação que possam promover cenas de atenção conjunta. Além disso, segundo dados do censo de educação básica de 2015, das quase 8 milhões de matrículas na Educação Infantil, cerca de 900 mil são para Educação Especial, sendo 700 mil no Ensino Fundamental e o preocupante afunilamento para 30 mil no 1º ano do Ensino Médio. Esses números reafirmam a importância da inclusão social e acredita-se que este decréscimo esteja relacionado à necessidade de um apoio tecnológico contextualizado nas atividades comunicativas e de atenção conjunta A metodologia de pesquisa é de natureza qualitativa, e utilizou o método de estudo de caso, de múltiplos casos. A atividade educativa foi desenvolvida por meio da contação de história infantil e uso de recurso tecnológico, dispositivo robótico, de ação mediadora, denominado de Fantoche Eletrônico, especialmente projetado para esta investigação. A práxis teve como base sociocognitiva as três etapas de intenção comunicativa da aquisição da linguagem proposta por Tomasello e de indicadores para a análise do estado afetivo de interesse. Os dados foram coletados por meio de instrumentos de entrevistas e observação sob a contação de quatro histórias infantil para quatro estudantes com autismo do 7º e 8º anos do ensino fundamental, totalizando 16 casos. Os resultados demonstraram que o uso do Fantoche Eletrônico promoveu mais de 80% de cenas de atenção conjunta, e um aumento, de três casos positivos com fantoche não eletrônico para quase 10 com o Fantoche Eletrônico, representado um ganho de mais de 200%. Além disso, 83% dos casos apresentaram indicativo positivo de estado afetivo de interesse. A Plataforma Educacional Assistiva foi denominada de Asistranto, assistência em Esperanto, e se mostrou adequada para o desenvolvimento de diferentes atividades acadêmicas com o objetivo de incluir estudantes com autismo em espaços escolares. / Technology, in its evolution and transformation, influences new developments in the techniques, processes and applications, not only in industry, but also in social and cultural processes. The use of Information Technology and Communication in Education, Engineering and Affective Computing models as a resource of mediating action to promote the social human being. In this context, the present developed, in the light of Socio-Historical Theory, an Assistive Educational Platform capable of to promote the affective state of interest in children with Autistic Spectrum Disorder(ASD) of the initial years of Elementary School. The ASD leads to a condition of development, demonstration scale, behavioral, communicative and or cognitive. The deficit of "joint attention", emotional reciprocity, of interest, and qualitative impairment in verbal and non-verbal communication verbal characteristics are widely mentioned in the literature. To "compensate" this gap, the teacher (as well as parents and therapists) must face the challenge of designing interaction strategies that can promote scenes of joint attention. Besides that, according to data from the 2015 basic education census, of the almost 8 million enrollments in the Education, about 900 thousand are for Special Education, of which 700 thousand are Elementary School and the worrying bottleneck for 30 thousand in the first year of high school. Those reaffirm the importance of social inclusion and it is believed that this related to the need for technological support contextualized in the activities communicative and joint attention. The research methodology is qualitative in nature, and used multiple cases study technique The educational activity was developed through the account of children's history and the use of technological resources, device robotic, of mediating action, denominated of Electronic Puppet, specially designed for this research. The praxis was based on sociocognitive three stages of communicative intention of language acquisition proposed by Tomasello and of indicators for the analysis of the affective state of interest. The data were collected by medium of instruments of interviews and observation under the account of four children's stories for four students with autism in the 7th and 8th years of elementary school, totaling 16 cases. The results showed that the use of the Electronic Puppet promoted more than 80% of scenes of joint attention, and an increase, of three positive cases with non-electronic puppet for almost 10 with the Electronic Puppet, represented a gain of over 200%. In addition, 83% of the cases presented positive indicative affective status of interest. The Assistive Educational Platform was denominated Asistranto, assistance in Esperanto, and proved adequate for the development of different activities with the aim of including students with autism in school settings.

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