Fêmeas suínas gestantes são frequentemente submetidas a uma restrição alimentar, que pode comprometer o bem-estar e produtividade. Existe pouca informação em relação as consequências da fome nas fêmeas gestantes nas medidas de bem-estar dos leitões. Dietas ricas em fibra podem minimizar a sensação de fome e, consequentemente, melhorar o bem-estar e a produtividade. Os objetivos deste estudo foram: 1) avaliar o impacto de uma dieta alta fibra (AF) para marrãs gestantes em medidas de bem-estar e 2) avaliar as consequências da dieta contendo AF durante a gestação no comportamento agonístico e indicadores de medo nos leitões ao desmame. Vinte e oito marrãs gestantes foram alimentadas com diferentes dietas: dieta AF, contendo 12,86% de fibra bruta (n=16), ou dieta baixa fibra (BF), contendo 2,53% de fibra bruta (n=12). Investigamos o impacto da AF ou BF nos seguintes parâmetros nas marrãs gestantes: comportamento; concentração do cortisol salivar; desempenho; motivação alimentar durante um teste de consumo ad libitum. Também avaliamos medidas de comportamento e desempenho da prole de 22 fêmeas (AF=14, BF=8). Lesões de pele foram avaliadas antes e após o desmame em 156 (100 AF e 56 BF), e 142 leitões foram submetidos ao teste de campo aberto e objeto novo (87 AF e 55 BF). Houve uma interação entre tratamento e tempo de alimentação para duração e frequência do comportamento mastigação em falso, indicando que as fêmeas que receberam a dieta BF apresentaram o comportamento mastigação em falso por mais tempo e com maior frequência antes da alimentação comparada com após a alimentação. Isso não foi observado nas fêmeas alimentadas com dieta AF. Para a maioria dos comportamentos avaliados, houve um efeito do momento de alimentação na duração e frequência. Não houve diferença na concentração de cortisol salivar entre os tratamentos. Os dados de desempenho indicam que as fêmeas AF foram mais pesadas no terço final de gestação e aos 107 dias de gestação, quando elas foram transferidas para a maternidade, comparadas com fêmeas BF. Não houve diferença nos outros parâmetros de desempenho. Não houve efeito do tratamento no total de alimento consumido durante o teste ad libitum. Não houve efeito do tratamento no desempenho dos leitões. Leitões nascidos de marrãs que receberam a dieta AF apresentaram menor número de lesões de pele antes do desmame comparados à prole de fêmeas BF. No teste de campo aberto e objeto novo, não houve efeito do tratamento no comportamento dos leitões. Esses resultados indicam que uma dieta AF foi eficaz em reduzir o comportamento anormal em marrãs e os leitões nascidos de fêmeas alimentadas com dieta AF demonstraram menor comportamento agressivo antes do desmame. / Pregnant sows are often subjected to food restriction, which can compromise their welfare and performance. Limited information is available on the consequences of sow hunger during pregnancy on welfare outcomes for their piglets. High fibre diets can mitigate the feeling of hunger and, consequently, improving welfare and productivity measures. The aims of this study were: 1) to measure the impact of feeding pregnant gilts with high fibre diet (HFD) on welfare measures, and 2) to assess the consequences of feeding gilts with HFD during pregnancy on agonistic behaviour and indicators of fear in their piglets at weaning. Twenty-eight pregnant gilts were fed either HFD, 12,86% of crude fibre (n=16) or low fibre diet (LFD), 2,53% of crude fibre (n=12). We investigated the impact of HFD and LFD on the following parameters in pregnant gilts: behaviour; salivary cortisol concentration; performance; and feeding motivation during an ad libitum test. We also assessed some behavior and performance measures in the offspring of 22 sows (HFD=14 LFD=8). Skin lesions were evaluated before and after weaning in 156 piglets (100 HFD and 56 LFD), and 142 piglets were subjected to an open field and novel object test (87HFD and 55 LFD). There was an interaction between treatment and feeding time, for duration and frequency of sham chewing abnormal behaviour, indicating that sows that received LFD performed the behaviour for longer and more often before feeding than after feeding. This was not observed in HFD fed sows. For most behaviours evaluated, there was an effect of feeding time in their duration and frequency. There was no difference in salivary cortisol concentration among treatments. The performance data indicated that HFD fed pregnant gilts were heavier in the last third of gestation and at 107th days of gestation, when they were moved to farrowing pens, than LFD fed pregnant gilts. There was no difference in other performance parameters. There was no effect of treatment on total food consumption during the ad libitum test. There was no treatment effect on the piglet\'s performance. Piglets born from gilts that received HFD had less skin lesions before weaning that the offspring of LFD pregnant gilts. In the open field and novel object tests, there was no treatment effect on the behaviour of piglets. These results indicate that HFD was beneficial in reducing abnormal behaviour is sows and that piglets born from gilts fed with HFD showed less aggressive behaviour prior to weaning.

abstract: The main objective of this study was to use a genetically-informative design to examine the putative influences of maternal perceived prenatal stress, obstetrical complications, and gestational age on infant dysregulation, competence, and developmental maturity. Specifically, whether or not prenatal and obstetrical environmental conditions modified the heritability of infant outcomes was examined. A total of 291 mothers were interviewed when their twin infants were 12 months of age. Pregnancy and twin birth medical records were obtained to code obstetrical data. Utilizing behavioral genetic models, results indicated maternal perceived prenatal stress moderated genetic and environmental influences on developmental maturity whereas obstetrical complications moderated shared environmental influences on infant competence and nonshared environmental influences on developmental maturity. Gestational age moderated the heritability and nonshared environment of infant dysregulation, shared and nonshared environmental influences on competence, and nonshared environmental influences on developmental maturity. Taken together, prenatal and obstetric conditions were important nonlinear influences on infant outcomes. An evolutionary perspective may provide a framework for these findings, such that the prenatal environment programs the fetus to be adaptive to current environmental contexts. Specifically, prenatal stress governs gene expression through epigenetic processes. Findings highlight the utility of a genetically informative design for elucidating the role of prenatal and obstetric conditions in the etiology of infant developmental outcomes. / Dissertation/Thesis / Ph.D. Psychology 2011

Fêmeas suínas gestantes são frequentemente submetidas a uma restrição alimentar, que pode comprometer o bem-estar e produtividade. Existe pouca informação em relação as consequências da fome nas fêmeas gestantes nas medidas de bem-estar dos leitões. Dietas ricas em fibra podem minimizar a sensação de fome e, consequentemente, melhorar o bem-estar e a produtividade. Os objetivos deste estudo foram: 1) avaliar o impacto de uma dieta alta fibra (AF) para marrãs gestantes em medidas de bem-estar e 2) avaliar as consequências da dieta contendo AF durante a gestação no comportamento agonístico e indicadores de medo nos leitões ao desmame. Vinte e oito marrãs gestantes foram alimentadas com diferentes dietas: dieta AF, contendo 12,86% de fibra bruta (n=16), ou dieta baixa fibra (BF), contendo 2,53% de fibra bruta (n=12). Investigamos o impacto da AF ou BF nos seguintes parâmetros nas marrãs gestantes: comportamento; concentração do cortisol salivar; desempenho; motivação alimentar durante um teste de consumo ad libitum. Também avaliamos medidas de comportamento e desempenho da prole de 22 fêmeas (AF=14, BF=8). Lesões de pele foram avaliadas antes e após o desmame em 156 (100 AF e 56 BF), e 142 leitões foram submetidos ao teste de campo aberto e objeto novo (87 AF e 55 BF). Houve uma interação entre tratamento e tempo de alimentação para duração e frequência do comportamento mastigação em falso, indicando que as fêmeas que receberam a dieta BF apresentaram o comportamento mastigação em falso por mais tempo e com maior frequência antes da alimentação comparada com após a alimentação. Isso não foi observado nas fêmeas alimentadas com dieta AF. Para a maioria dos comportamentos avaliados, houve um efeito do momento de alimentação na duração e frequência. Não houve diferença na concentração de cortisol salivar entre os tratamentos. Os dados de desempenho indicam que as fêmeas AF foram mais pesadas no terço final de gestação e aos 107 dias de gestação, quando elas foram transferidas para a maternidade, comparadas com fêmeas BF. Não houve diferença nos outros parâmetros de desempenho. Não houve efeito do tratamento no total de alimento consumido durante o teste ad libitum. Não houve efeito do tratamento no desempenho dos leitões. Leitões nascidos de marrãs que receberam a dieta AF apresentaram menor número de lesões de pele antes do desmame comparados à prole de fêmeas BF. No teste de campo aberto e objeto novo, não houve efeito do tratamento no comportamento dos leitões. Esses resultados indicam que uma dieta AF foi eficaz em reduzir o comportamento anormal em marrãs e os leitões nascidos de fêmeas alimentadas com dieta AF demonstraram menor comportamento agressivo antes do desmame. / Pregnant sows are often subjected to food restriction, which can compromise their welfare and performance. Limited information is available on the consequences of sow hunger during pregnancy on welfare outcomes for their piglets. High fibre diets can mitigate the feeling of hunger and, consequently, improving welfare and productivity measures. The aims of this study were: 1) to measure the impact of feeding pregnant gilts with high fibre diet (HFD) on welfare measures, and 2) to assess the consequences of feeding gilts with HFD during pregnancy on agonistic behaviour and indicators of fear in their piglets at weaning. Twenty-eight pregnant gilts were fed either HFD, 12,86% of crude fibre (n=16) or low fibre diet (LFD), 2,53% of crude fibre (n=12). We investigated the impact of HFD and LFD on the following parameters in pregnant gilts: behaviour; salivary cortisol concentration; performance; and feeding motivation during an ad libitum test. We also assessed some behavior and performance measures in the offspring of 22 sows (HFD=14 LFD=8). Skin lesions were evaluated before and after weaning in 156 piglets (100 HFD and 56 LFD), and 142 piglets were subjected to an open field and novel object test (87HFD and 55 LFD). There was an interaction between treatment and feeding time, for duration and frequency of sham chewing abnormal behaviour, indicating that sows that received LFD performed the behaviour for longer and more often before feeding than after feeding. This was not observed in HFD fed sows. For most behaviours evaluated, there was an effect of feeding time in their duration and frequency. There was no difference in salivary cortisol concentration among treatments. The performance data indicated that HFD fed pregnant gilts were heavier in the last third of gestation and at 107th days of gestation, when they were moved to farrowing pens, than LFD fed pregnant gilts. There was no difference in other performance parameters. There was no effect of treatment on total food consumption during the ad libitum test. There was no treatment effect on the piglet\'s performance. Piglets born from gilts that received HFD had less skin lesions before weaning that the offspring of LFD pregnant gilts. In the open field and novel object tests, there was no treatment effect on the behaviour of piglets. These results indicate that HFD was beneficial in reducing abnormal behaviour is sows and that piglets born from gilts fed with HFD showed less aggressive behaviour prior to weaning.

No description available.

Prenatal stress may increase the risk for depression in offspring and it has been suggested that this could be linked to alterations in tryptophan metabolism, leading to serotonergic changes. Dietary patterns based on the Mediterranean (Med) diet, which includes foods rich in nutrients involved in the tryptophan-serotonin pathway, have been linked to depressive symptom improvements when used as an intervention. This thesis examined, in a mouse model, whether a Med-based diet normalized depressive-like behaviour and changes in the serotonin system in the colon and hippocampus resulting from a repeated physical restraint stressor administered during the second trimester in adult C57BL/6N female and male offspring. The Med-based diet modulated behaviour and hippocampal serotonin receptors primarily in females and changed the enzyme involved in the colonic serotonergic pathway in males. These results suggest that a Med-based diet may help improve behavioural disturbances stemming from prenatal stress in a sex-specific way, perhaps through its actions on the gut-brain serotonin system.

Introduction : En France, comme ailleurs, la prévalence de la dépression post-partum (DPP) (environ 10% des femmes) n'est pas plus importante que celle d'autres formes de dépression mais elle pose un important problème de dépistage car, les femmes consultent moins rendant difficile sa prévention. Les recherches visant à améliorer la prévention de la DPP s'appuient sur deux modèles principaux, le modèle de la vulnérabilité au stress et le modèle bio-psycho-social. L'un comme l'autre décrivent le stress psychologique prénatal comme étant un important déterminant de la DPP. Néanmoins, si le stress est fréquemment évalué, il n'est mesuré en général qu'une fois et tardivement dans la grossesse. Il n'est donc actuellement pas possible de connaître ni son évolution ni l'effet de cette évolution sur la DPP. En conséquence, un premier objectif de ce travail doctoral est d'identifier et de caractériser des trajectoires de stress afin d'évaluer leurs effets sur la DPP. Par ailleurs, certaines recherches montrent que les complications obstétricales lors de l'accouchement ont un effet délétère sur la santé psychologique des femmes en postpartum et d'autres que le stress prénatal augmente le risque de complications obstétricales. Nous faisons donc l'hypothèse qu'une élévation du stress associée à des complications obstétricales à l'accouchement augmente considérablement le risque de DPP, mais que cela diffère d'une femme à l'autre en fonction du niveau des déterminants du stress.Méthode : La santé des mères, leur trait d'anxiété et des variables socio-économiques ont été relevées chez 164 femmes avant la fin des deux premiers mois de la grossesse. Le stress perçu, l'état d'anxiété, le soutien social et les stratégies de coping ont été évalués à 2, 6 et 9 mois de grossesse pour 163 femmes puis à 1 et 6 mois postpartum pour 91 d'entre elles. Par ailleurs, les résultats du dépistage prénatal des pathologies fœtales, le terme de la grossesse, le poids de naissance du bébé, ses résultats à l'Apgar et le type d'accouchement (dystocique versus eutocique) ont également été relevés. Enfin, la mesure de la DPP a été effectuée 6 mois après l'accouchement. Nous avons calculé des trajectoires individuelles de stress et mesuré l'effet de ces trajectoires sur les variables liées à l'accouchement pour 163 femmes puis sur la DPP pour 91 d'entre elles.Résultats : Trois trajectoires ont été identifiées en prépartum comme en postpartum. Une première où le stress est faible en début de grossesse, augmente jusqu'en début de post-partum et diminue légèrement en fin de période postnatale. Une seconde où le stress est modéré en début de grossesse, diminue jusqu'au milieu de la grossesse, augmente en fin de grossesse et se stabilise en période postnatale. Une dernière où le stress est élevé en début de grossesse, puis diminue jusqu'en fin de grossesse et continue de diminuer en période postnatale. Lorsque le stress suit les trajectoires 2 et 3, la durée de gestation est plus courte, F(2,138) = 3,45, p < 0,05, η2 = 0,048, l'usage de la césarienne est plus fréquent, OR = 2,62,p < 0,05, IC95% = [1,01 – 6,75] ainsi que l'accouchement dystocique, OR = 3,54, p < 0,005, IC95% = [1,18 – 10,52]. En revanche, les trajectoires de stress n'ont pas d'effet sur la DPP.Discussion : Nos résultats sont encourageants et permettent de montrer que l'évolution de la perception du stress pendant la grossesse a un effet sur la durée de gestation, les complications obstétricales et l'usage de la césarienne. En revanche, elle n'en a pas sur la DPP. Cependant nos résultats suggèrent que le stress pourrait avoir un effet uniquement chez les femmes vulnérables et que la DPP s'insèrerait dans un continuum dépressif, alors contigu à la vulnérabilité au stress. Les recherches ultérieures devraient donc évaluer le lien entre des trajectoires individuelles de dépression et de stress du début de la grossesse en fin de postpartum afin de tester cette hypothèse. / Introduction : In France, as well as in other countries, the prevalence of postpartum depression (PPD) (about 10% of women) is not more important than other forms of depression, but it is a major problem of screening, because women less consult, making prevention difficult. Researches to improve the prevention of DPP are essentially based on two models, the stress-vulnerability model and the bio-psycho-social model. The both models describe the prenatal psychological stress as an important determinant of the PPD. However, if stress is frequently assessed, it is usually measured only once and late in pregnancy. So, by now, it is not possible to know its evolution or to know its effects on PPD. Accordingly, a primary objective of this doctoral work is to identify and characterize trajectories of stress to assess their effects on the DPP. Moreover, some researches showed that obstetric complications during childbirth have a deleterious effect on the psychological health of postpartum women. Others proved that prenatal stress increases the risk of obstetric complications. So we assume that an elevated stress associated with obstetric complications in childbirth significantly increases the risk of PPD. Neverthless it differs from one woman to another depending on the level of stress determinants.Method: The health of mothers, their anxiety-trait level and socio-economic variables were recorded among 164 women before the end of two months of pregnancy (T0). Perceived stress, state anxiety, social support and coping strategies were evaluated at 2, 6 and 9 months of pregnancy for 163 women and at 1 and 6 months postpartum for 91 of them. Moreover, the results of prenatal screening for fetal pathologies, the term of pregnancy, baby's birth weight, results of Apgar and type of delivery (dystocic versus eutocic) were recorded. Finally, the measurement of the PPD was performed 6 months after delivery. We calculated trajectories of stress and we measured the effect of these trajectories on the variables related to childbirth for 163 women and on DPP for 91 of them.Results: Three trajectories were identified in prepartum and postpartum. A first trajectory where the stress is low in early pregnancy, increases until early postpartum and decreased slightly at the end of the postnatal period. A second where the stress is moderate in early pregnancy decreases until the middle of pregnancy, increases in late pregnancy and postpartum. A final trajectory where stress is high in early pregnancy and then decreases until the end of pregnancy and continues to decrease in postpartum. When the stress follows the paths 2 and 3, the gestation period is shorter, F(2,138) = 3.45, p <0.05, η2 = 0.048, the use of cesarean section is more common, OR = 2.62, p < 0.05, CI 95% = [1.01- 6.75] as well as dystocic labor, OR = 3.54, p <0.005, CI 95% = [1.18-10.52]. In contrast, the trajectories of stress does not have an effect on the PPD.Discussion: Our results are encouraging and show that the perception of stress during pregnancy has an effect on the duration of pregnancy, obstetric complications and the use of cesarean section. However it has no effect on the DPP, but our results suggest that stress may have an effect only among vulnerable women and that the DPP would fit into a depressive continuum, while adjacent to the vulnerability to stress. In conclusion, future researches should assess the link between trajectories of stress and depression from early pregnancy to late postpartum to test this hypothesis.

Egg-laying hens coming from commercial hatchery go through hatchery procedures considered as stressful and engaging prolonged stress response in adult chickens. The aim of our study was to evaluate the impact of commercial hatching procedure on the affective state of chicks, on their short- and long-term memory and on their need for social reinstatement. To assess the affective state of the chicks we used a cognitive bias protocol integrating the ecological response of a chick to the picture of another chick, to an owl and to an ambiguous cue mixing features of both the chickand the owl pictures. Short-term memory was evaluated by using a delayed matching-to-sample experiment (with 10, 30,60 and 120 s delays), with conspecifics as sample stimuli. We assessed long-term memory with an arena containing multiple doors leading to conspecifics, in which a chick had to remember which door was open after a delay of one hour or three hours. Finally, we observed the need for social reinstatement through a sociality test arena allowing a chick to be more or less close to conspecifics. We found that chicks coming from commercial hatchery were in a depressive affective state compare to control group. Those chicks also showed higher need for social reinstatement and loss weight. No differences were found regarding short- and long-time working memory between the two groups, but the methods used during these experiments will be discussed. Studying how commercial procedures impact the cognition and more specifically the emotions and state of mind of chickens, is a necessary step forward into the understanding of farm animals’ welfare.

This research project explores the contribution of prenatal stress to the pathogenesis of autism as a neurobiological developmental disorder. The neurobiological impact of stress prior to the 28th week of gestation might produce structural neural changes, specifically regarding the cerebellum, the brain stem and limbic pathways, including the hippocampal area, which concept relates closely to the pathogenesis of autism. In this research project a significant focus is placed on prenatal hipothalamic-pituary-adrenal (HPA) activity due to the HPA axis’ interactivity with cortisol, digoxin and serotonin, as these biochemicals are significantly implicated in programmed foetal development, postnatal cortical behaviour, postnatal learning, as well as in functional impairment of socialization, communication and imagery associated with autism. Based upon the rationale of this research project and the conceptualisation of the topic of interest, the research problem was formulated as follows: In what unique ways does prenatal stress contribute to the pathogenesis of autism as a neurobiological developmental disorder? Sub questions included: Did the mother of the dizygotic twins experience significant stress during the period of gestation? What structural brain differences can be observed among the dizygotic twins at hand of MR-imaging? To which periods of prenatal development can these structural differences be related? How do these differences account for sensory, motor, cognitive, and affective behavioural differences among the dizygotic twins? What plasma differences can be observed among the dizygotic twins at hand of blood sampling? How does elevation of pre- and postnatal glucocorticoids relate to plasma difference among the dizygotic twins? How do these plasma differences account for sensory, motor, cognitive, and affective behavioural differences among the dizygotic twins? This research project represents quantitative research. The mode of inquiry is non-experimental at hand of a single dizygotic twin study. The following data generating strategies were employed: clinical intake interviews, administration of a diagnostic stress inventory and the 16-PF Questionnaire, MR-imaging, and the collection of blood plasma pathology results. / Dissertation (M.Ed)--University of Pretoria, 2006. / Educational Psychology / unrestricted

Environmental stress has shown to affect both the exposed individuals and the development of their offspring. Generally, it is thought that the stressed organism responds to stress by trying to adapt to it. This thesis investigates possible evolutionary consequences of cross-generational transmissions of stress, where the parent has been stressed but the offspring has not. In two studies we have exposed chicken parents of different breeds to an unpredictable circadian light rhythm, to investigate the influence of genetic background on the transmission of behaviour and patterns of genome-wide gene expression across generations. In Paper I, we can show that the domesticated chicken, by means of epigenetic factors, transmit their behaviours as well as their gene expression profiles to their offspring to a higher extent than their wild ancestor, the red junglefowl. Furthermore, in Paper II, even though the offspring never experienced the stress or had any contact with their stressed parents, they seemed to have adapted to it, which suggests that the parents might have prepared (or pre-adapted) them for living in the unpredictable environment. Additionally, eggs of stressed hens showed increased levels of estradiol that might have affected gene expression of specific immune genes, which were up-regulated in the offspring of stressed parents. It is possible that the traditional distinction between stress responses and evolutionary adaptation may be reevaluated, since our results indicate that they could be parts of the same evolutionary event.

<p>Environmental stress has shown to affect both the exposed individuals and the development of their offspring. Generally, it is thought that the stressed organism responds to stress by trying to adapt to it. This thesis investigates possible evolutionary consequences of cross-generational transmissions of stress, where the parent has been stressed but the offspring has not. In two studies we have exposed chicken parents of different breeds to an unpredictable circadian light rhythm, to investigate the influence of genetic background on the transmission of behaviour and patterns of genome-wide gene expression across generations. In Paper I, we can show that the domesticated chicken, by means of epigenetic factors, transmit their behaviours as well as their gene expression profiles to their offspring to a higher extent than their wild ancestor, the red junglefowl. Furthermore, in Paper II, even though the offspring never experienced the stress or had any contact with their stressed parents, they seemed to have adapted to it, which suggests that the parents might have prepared (or pre-adapted) them for living in the unpredictable environment. Additionally, eggs of stressed hens showed increased levels of estradiol that might have affected gene expression of specific immune genes, which were up-regulated in the offspring of stressed parents. It is possible that the traditional distinction between stress responses and evolutionary adaptation may be reevaluated, since our results indicate that they could be parts of the same evolutionary event.</p>