• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 22
  • 3
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 35
  • 35
  • 28
  • 6
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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.
21

Social context affects behavioral responsiveness to maternal alarm calls in Bobwhite quail chicks

Casey, Michael Bernard 04 May 2010 (has links)
These studies examined the effects of altered developmental experience (rearing history) and altered behavioral context (testing environment) on the alarm call responsiveness of maternally naive, incubator-reared bobwhite quail chicks. Experiment 1 assessed alarm call responsiveness in socially-reared, socially-tested hatchlings across the first 96 hours following hatch. No significant age effects were revealed. Hatchlings tested at 24 hours did not differ significantly from birds tested at 48, 72, or 96 hours on the two principle behavioral measures (number of grid crossings and vocalizations per one-minute trials). Experiment 2 assessed whether hatchlings' alarm call responsiveness is at least partially dependent on the availability of cover (i.e., hiding sites) in the testing situation. No significant differences in responding were found in comparisons between hiding sites and social (non-hiding sites) testing conditions. However, behavioral observations did indicate that hatchlings in the hiding site condition utilized the hiding site as an attractor, in that chicks typically huddled and froze around the hiding site structure. Experiment 3 examined the relative effects of individual testing on socially-reared bobwhite quail hatchlings. Results revealed that individually tested hatchlings increased their locomotor activity following initial exposure to the maternal alarm call when compared to socially tested chicks. Vocalizations were significantly reduced in post-alarm call testing from pre-alarm call levels. However, hatchlings tested individually had higher levels of vocal activity when compared to socially tested chicks. In comparison with socially-reared/socially-tested subjects, socially-reared/individually tested subjects were more active following exposure to the maternal alarm call than they were prior to exposure to the call. Results from the three experiments are discussed in terms of species-typical experience and development. It is maintained that species-typical responding to the bobwhite maternal alarm call is partially influenced by social context. An argument for continued polythetic research on behavioral development in avian communication is also made. / Master of Science
22

Comparison of maternal performance of reciprocal crossbred cows

Leonard, Bobby Elwood 17 February 2010 (has links)
Maternal performance of reciprocal two-breed cross cows between Angus, Herefords and Shorthorns was compared in 249 matings over a four year period. These cows were mated to bulls of the same three breeds to produce three-breed and baekcross calvea. Shorthorn x Angus cows (sire breed first) weaned l7.S~ fewer calve. and Hereford x Angus cows 10.31 fewer calves than their respective reciprocal crosses. Thete differencea while large were not statistically significant presumably due to the small numbers involved. There was little difference between Shorthorn x Hereford and Hereford x Shorthorn cows in percentage calf crop_ The calves from Shorthorn x Angua cows were significantly heavier at birth than the calves from their reciprocals. Birth weight differences of calves from the other two sets of rec1proc41 eros. cows were not significantly different. Differences in average daily gain from birth to weaning were highly significant in calves from Angus x Hereford cows over calves from Hereford x Angus cows as well as Shorthorn x Hereford over Hereford x Shorthorn. The third set of reCiprocal crossea, Angus x Shorthorn versus Shorthorn x Hereford, did not show significant differences in average daily gains. / Master of Science
23

Molecular Dissection of Neural Circuits Underlying Parental Behavior in Mice

Wu, Zheng January 2013 (has links)
Mice display robust and stereotyped behaviors towards pups: virgin males typically attack pups, while virgin females and sexually experienced males display parental care. I show here that virgin males that are genetically impaired in vomeronasal sensing do not attack pups and are parental, suggesting a key role of the vomeronasal system in controlling male infanticide. In addition, we have identified putative vomeronasal receptors (or receptor groups) for the detection of pup odors, thus uncovering new tools for the molecular and genetic dissection of male infanticide. Further, we have uncovered galanin-expressing neurons in the medial preoptic area (MPOA) as key regulators of male and female parental behavior. Genetic ablation of MPOA galanin- neurons results in dramatic impairment of parental responses in both virgin females and sexually experienced males. In addition, optogenetic activation of these cells in virgin males suppresses infanticide and induces pup grooming. Thus, MPOA galanin-expressing neurons emerge as an essential node of regulation of innate behavior in the hypothalamus that orchestrates male and female parenting while opposing vomeronasal circuits underlying infanticide. Our results provide an entry point for the genetic and circuit-level dissection of mouse parental behavior and its modulation by social experience.
24

Maternal strategies in vervet monkeys

Sashaw, Jessica Joan Hayden January 2012 (has links)
I studied free-ranging vervet monkeys (Chlorocebus aethiops) in South Africa using focal animal sampling to test current theories of reproduction and maternal investment. Mothers cope with the energetic costs of lactation by feeding more than non-lactating females and targeting higher nutrient quality items as their infant ages. The dynamic nature of mother-infant interactions is highlighted, with infants spending less time in contact while the mother is moving and foraging. Other troop members “allomother” the infant primarily in the infant’s first couple of months. The length of investment is explored, with greater length of interbirth interval in low nutrient quality environments, larger troop sizes and higher survival rates. Maternal dominance rank and infant sex significantly influenced time in ventral contact, with low-ranking daughters spending more time in contact than high-ranking daughters. The findings from this thesis highlight the complex interaction of ecological and social conditions on maternal investment. / xiv, 182 leaves ; 29 cm
25

Penguin parenting : assortative mating, nest attendance and sex-specific chick provisioning in the African Penguin (Spheniscus demersus)

Smith, Diane Lauren January 2016 (has links)
Animal behaviour is especially sensitive to environmental variability and prey availability during the breeding season, and this is particularly true for non-volant, central place foragers such as the endangered African Penguin (Spheniscus demersus). Individual sex and morphology, as well as the level of assortment within mated pairs can influence both the behaviour and the reproductive success of species exhibiting biparental care. This study made use of a large biometric database and nest attendance video footage to determine the influence of intrinsic (assortative mating, brood size and chick age) and extrinsic (environmental conditions, anthropic disturbance) factors on breeding behaviour and performance of African Penguins on Bird Island, Algoa Bay, during peak breeding (March - July) in 2013. While sexual dimorphism in African Penguins is subtle, the colony-specific discriminant functions presented here provide an accurate sexing tool when only bill and flipper length are available. Despite the premise that selection of a large, high-quality mate in this longlived, monogamous seabird governs lifetime fitness, only low levels of assortative mating were found, and this only for earlier breeders, when larger females (but not males) bred. The 2013 season was a particularly successful one, coinciding with above-average sardine and anchovy abundance, and almost 80 percent of monitored nests were double-brooded, with very low levels of mortality. A- and B-chicks of double broods and singleton chicks grew at similar rates and exhibited similar body condition indices. In these conditions, chick developmental rates were independent of parental size, assortment or provisioning behaviour. Females raising a double brood were significantly lighter and in poorer body condition than those raising a single chick, although the same trend was not evident in males. Offspring sex ratio in 2013 (2.27:1) favoured male chicks, suggesting that there is potential to over-produce the larger sex when resources are plentiful. Peak nest arrival and departure times of parents did not change over the course of monitored breeding attempts (March-June), nor were they different for disturbed and undisturbed nests or for a single or double brood. The increase in CCTV-observed provisioning rate as chicks grew larger was best explained by brood size, at-sea chlorophyll a concentration, and maximum air temperature, but was unrelated to parental morphology or assortative index. Importantly, parental absenteeism commenced earlier and was markedly greater in nests frequently handled by researchers than in undisturbed nests. Both the time spent together by parents, and absenteeism were measurably affected by maximum afternoon air temperatures, the effects of which are expected to be exacerbated by poorer foraging conditions and climate change. A third of manually-monitored nests shared chick-guarding duties unequally, although this phenomenon was independent of parental sex or morphology. The adaptive benefits of mating patterns and division of labour during chick-rearing may only become apparent in a year of below-average food availability and it is highly recommended that this study be repeated in a year of scarce food resources. These findings augment past foraging ecology studies and demonstrate that investigator disturbance and environmental conditions can affect the nesting behaviour of this highly threatened seabird.
26

Social relationships of infants of resident females and infants of immigrant females in mountain gorillas (Gorilla gorilla beringei)

Anness, Lorna Margaret 01 January 1990 (has links)
This study compares social behavior of infants of resident mothers and infants of immigrant mothers in social groups of the mountain gorilla, Gorilla gorilla beringei. Infants of immigrant mothers spent more time in proximity to their mothers during group resting. They spent more time in solo play and less time in social play during group feeding. Their opportunity for social interaction with peers may be restricted mostly to group rest periods and their social play levels during this time are higher than infants with resident mothers. However, during both group resting and feeding they spent less time near other infants and they initiated fewer dyadic play bouts.
27

Does parental behavior moderate the association between psychopathic traits andantisocial behavior in adolescents?

Cressell, Samantha, Nordkvist, My January 2021 (has links)
This study examines the moderating effect of six different parental behaviors on the level ofantisocial behavior in adolescents with psychopathic traits. Participants were 839 adolescents froma mid-sized town in Sweden between the ages of 13 - 15 years (M = 14.2, SD = .94). Parentalbehaviors and antisocial behavior were measured through adolescents' self-reports, psychopathictraits were measured using the Youth Psychopathic traits Inventory (YPI). The result from themoderation analysis showed that the three negative parental behaviors (bad reactions to disclosure,angry outbursts and coldness-rejection) had a significant positive moderating effect on the level ofantisocial behavior that the adolescents engaged in. The three positive parental behaviors (warmth,attempted understanding and control) however, did not have a significant moderating effect on thelevel of antisocial behavior. In sum, the result from this study suggests that negative parentalbehavior acts as risk factors for adolescents with psychopathic traits to engage in higher levels ofantisocial behavior. Furthermore, positive parental behaviors do not have a buffering effect againstantisocial behavior among these youths, indicating that it may be beyond the parents’ control toprevent the negative development of antisocial behavior among these youths.
28

Behavioral Alterations in Prairie Voles (Microtus ochrogaster) after Parent-Pup Separation

Yamamoto, Mihoko 01 January 2009 (has links) (PDF)
The prairie vole (Microtus ochrogaster), a highly social species, offers a unique opportunity to examine the effects of parent-pup separation in a biparental family system similar to humans. We hypothesized that 1) repeated separation from pups affects parental behavior and emotionality in parents, and 2) neonatal parental separation affects emotional and physiological development in pups, and thus induces altered adult parental, emotional, and social behaviors. During postnatal day (PND) 1-10, pups were removed from their parents for 0, 15, or 360 min and housed either individually or with siblings. Unhandled controls experienced only daily lid opening. Tests for parental responsiveness and emotionality were conducted on PND11 for parents and PND90-92 for their offspring. Emotionality tests included the elevated plus maze, open field, and forced swim tests. Starting at PND150, half of each litter was paired with an opposite-sex vole for 24 hours and tested for partner preference. Additionally, behavioral response to stress was measured in all animals 0, 30, or 60 min after exposure to a forced swim. Generally, the behavior of the parents and adult offspring was influenced by daily handling, the length of the separation, and presence of siblings. Parental behaviors in parents did not differ among groups, while their anxiety- and depression-like behaviors were influenced by pup separation. For the adult offspring, separation treatment altered parental behavior, emotionality, partner preference, and stress response. Our results demonstrated that parent-pup separation affects emotional and social behaviors in prairie vole parents and adult offspring.
29

PARENT-ADOLESCENT CONFLICT IN KENYA: THE EFFECT OF PARENTAL BEHAVIOR ON ADOLESCENT’S AUTONOMY AND CONFORMITY

Dotse, Nathaniel 22 November 2016 (has links)
No description available.
30

Étude des liens entre les difficultés d’attention et le stress chez les jeunes, de la maternelle à l’université : rôles des comportements parentaux et des problèmes de sommeil / Study of the links between attention difficulties and stress in young people, from kindergarten to university : roles of parental behavior and sleep problems

Meyer, Eric 06 December 2018 (has links)
Ces dernières années, la santé des jeunes générations est devenue une priorité et il est important de pouvoir mieux identifier les signes de mal-être et/ou de souffrance des jeunes. L’étude de ces problématiques de souffrance est d’autant plus importante que la réussite des jeunes passe par le fait d’être en bonne santé. Nous avons choisi de nous centrer sur deux dimensions de ces problématiques qui impactent la scolarité et l’efficacité des jeunes de la maternelle à l’université : le stress et les difficultés d’attention. Bien que la littérature aborde majoritairement la problématique des difficultés d’attention sous l’angle du Trouble de l’Attention avec ou sans Hyperactivité (TDAH), elles regroupent également les difficultés pouvant être présentes dans l’ensemble des dimensions cognitives propre à l’attention, et, peuvent être inhérentes à d’autres souffrances psychiques comme la dépression, l’anxiété, les troubles psychotiques. En considération avec la littérature récente, pour nous, les difficultés d’attention correspondent à un continuum dont une extrémité serait le TDAH, pouvant ainsi être défini selon le niveau de symptomatologie du TDAH. Le stress est défini et évalué de manière multiple, selon des marqueurs physiologiques, ou encore par des inventaires d’événement de vie. Pour des raisons théoriques, nous le définissons par le concept de stress perçu et ressenti. Il ressort que les liens entre le stress et les difficultés d’attention ne sont pas clairs. Certaines études mettent en avant un impact du stress sur les difficultés d’attention, d’autres des difficultés d’attention sur le stress. Afin d’approfondir ces liens, nous avons isolé deux prédicteurs de la symptomatologie du TDAH en lien avec le stress : les comportements parentaux et les problèmes de sommeil. Toutefois, il n’existe à notre connaissance aucune étude ayant travaillé les liens entre le stress, la symptomatologie du TDAH et les problèmes de sommeil, et, entre le stress, la symptomatologie du TDAH et les comportements parentaux. Afin d’étudier ces liens et comprendre l’articulation du stress et de la symptomatologie du TDAH (difficultés d’attention et comportements d’hyperactivité), nous avons réalisé trois études: deux en population générale, auprès d’enfants en maternelle (3-6 ans) et auprès d’étudiants à l’université, et, une auprès d’enfant et d’adolescents (6-16 ans) présentant des difficultés scolaires. Nos études montrent que le stress est fortement associé aux difficultés d’attention et moins aux comportements d’hyperactivité chez les 3-6 ans et chez les étudiants. Chez les 6-16 ans, le stress perçu n’est pas associé à la symptomatologie du TDAH au contraire des difficultés émotionnelles mesurées par les parents qui sont associées aux difficultés d’attention et aux comportements d’hyperactivité. Les problèmes de sommeil sont associés aux difficultés d’attention et aux comportements d’hyperactivité chez les étudiants, ils ne sont associés qu’aux comportements d’hyperactivité chez les 3-6 ans et qu’aux difficultés d’attention chez les 6-16 ans. Nos résultats montrent la présence d’une médiation partielle chez les étudiants que nous ne retrouvons pas chez les enfants et adolescents. Les comportements parentaux, principalement coercitifs, sont associés avec les comportements d’hyperactivité et d’inattention. Et il semble que le stress soit un médiateur partiel entre les comportements parentaux et la symptomatologie du TDAH. Ainsi l’ensemble de nos études montrent l’importance de considérer les difficultés d’attention selon un continuum et de tenir compte du stress et des difficultés de sommeil lorsque nous évaluons la présence de difficultés d’attention. Ces deux variables peuvent augmenter la sévérité des difficultés d’attention, pouvant peut-être provoquer un TDAH-like. Ce travail de thèse fait également ressortir un champ d’intervention possible par la prise en compte simultanée des difficultés d’attention, du stress et des problèmes de sommeil. / In recent years, the health of younger generations has become a priority and it seems more important to identify the signs of malaise and / or suffering of young people. The study of these problems of suffering is all the more important that the success of young people is through being healthy. We chose to focus our work on two dimensions that impact the education and effectiveness of young people from kindergarten to university: stress and attention difficulties.Although the literature mainly addresses the problem of attention difficulties from the angle of Attention Disorder with or without Hyperactivity (ADHD), attention difficulties also group the difficulties that can be present in all the cognitive dimensions specific to attention, and, may be inherent to other psychological pains such as depression, anxiety, psychotic disorders. In consideration with recent literature, for us attention difficulties correspond to a continuum of which one pole is ADHD, thus being able to be defined according to the level of symptomatology of ADHD.Stress is defined and evaluated in multiple ways, according to physiological markers, or by life event inventories. For theoretical reasons, we define it by the concept of perceived and felt stress.It appears that the links between stress and attention difficulties are unclear. Some studies highlight an impact of stress on attention difficulties and others attention difficulties on stress.In order to understand these links, we isolated two predictors of ADHD symptomatology related to stress: parental behaviors and sleep problems. However, to our knowledge, there are no studies that have worked on the links between stress, symptomology of ADHD and sleep problems, and, between stress, ADHD symptomatology and parental behavior.In order to study these links and to understand the articulation of stress and ADHD symptomatology (attention difficulties and hyperactivity behaviors), we conducted three studies: two in the general population, with children in kindergarten (2 at age 6) and with university students, and one with children and adolescents between the ages of 6 and 16 with learning difficulties.Our studies show that stress is strongly associated with attention difficulties and less with hyperactivity in 2 to 6-year old and students. In the age group 6 to 16, perceived stress is not associated with ADHD symptomatology, unlike emotional difficulties measured by parents that are associated with attention difficulties and hyperactivity behaviors. Sleep problems are associated with attention difficulties and hyperactivity behaviors in students, they are associated with hyperactivity behaviors in 2-6 years of age and attention difficulties in 6- 16 years old. Our results show the presence of partial mediation among students that we do not find in children and adolescents. Parenting behaviors, mainly coercive, are associated with hyperactivity and inattention behaviors. And it seems that stress mediate partially the relationship between parenting behaviors and the symptomatology of ADHD.Thus, all of our studies show the importance of considering attention difficulties along a continuum and considering stress and sleep difficulties when assessing the presence of attention difficulties. These two variables may increase the severity of attention difficulties, possibly leading to ADHD-like. This thesis work also highlights a possible field of intervention by simultaneously considering the difficulties of attention, stress and sleep problems.

Page generated in 0.0617 seconds