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It was the purpose of this study to determine whether the early loss of the father is conducive to injury of personality development of boys and girls, which injury may still be evident in late adolescence, the crucial time in life when educational, vocational and other important decisions are being made.

Submitted by Gizele Lima (gizele.lima@inpa.gov.br) on 2017-09-04T13:34:27Z No. of bitstreams: 2 Dissertação - Comportamento Reprodutivo Allobates paleovarzensis - SulamitaRocha.pdf: 1777199 bytes, checksum: 751475a87c059b2892d3ed238c71732c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-04T13:34:27Z (GMT). No. of bitstreams: 2 Dissertação - Comportamento Reprodutivo Allobates paleovarzensis - SulamitaRocha.pdf: 1777199 bytes, checksum: 751475a87c059b2892d3ed238c71732c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-07-21 / The study of amphibians’ reproductive biology allows to outline patterns among different taxonomical groups and to test many evolutionary and behavioural hypotheses. In this study, we used the species Allobates paleovarzensis (Anura: Aromobatidae) as a model due to its parental care and male territoriality. We conducted behavioural observations and field experiments during reproductive seasons in two localities, where we described courtship behaviour, mating, parental care and territoriality (Chapter I); tested the role of intrinsic and extrinsic characteristics of the males in mating success (Chapter 2); and tested the effect of males’ removal in the survival rate of the offspring and in the parental behaviour of females (Chapter 3). Most of the studies concerning these topics in anurans were conducted in captivity, and field experiments are important for testing behavioural relations and survival rates under natural biotic and abiotic conditions. Our observations show that A. paleovarzensis is a polygamical species with uniparental care by the males, territoriality related to male competition for space and females, high investment on the number of eggs with evidence of the simultaneous transport of the highest number of tadpoles for the genus. Territory size is the main driver for males’ mating success, and this determinant was uncorrelated with other tested attributes. Females appear to access males’ territorial size during courtship, before mating, when males conduct females around the territory. Parental care in A. paleovarzensis is exclusive to males, with no evidence for maternal care. Males nurse the offspring throughout the whole developmental process that occur inside their territories. Without a male providing parental care, offspring mortality is very high in every developmental stage. / O estudo da biologia reprodutiva dos anfíbios permite delinear padrões entre os diferentes grupos taxonômicos e testar diversas hipóteses evolutivas e comportamentais. Nesse estudo utilizamos a espécie Allobates paleovarzensis (Anura: Aromobatidae) como modelo, uma vez que esta exibe cuidado paternal e territorialidade masculina. Realizamos observações comportamentais e experimentos em campo nos períodos de atividade reprodutiva em duas localidades, onde descrevemos o comportamento de corte, acasalamento, cuidado parental e territorialidade (Capítulo 1); testamos o papel de características intrínsecas e extrínsecas do macho sobre o sucesso de acasalamento (Capítulo 2); e testamos o efeito da remoção de machos parentais na sobrevivência da prole e no comportamento parental da fêmea (Capítulo 3). A maior parte dos estudos sobre esses tópicos em anuros foram conduzidos em cativeiro, e experimentos de campo são importantes para testar as relações comportamentais e a sobrevivência sob condições bióticas e abióticas naturais. Nossas observações indicam que A. paleovarzensis é uma espécie poligâmica de cuidado uniparental realizado pelo macho, territorialidade relacionada à competição masculina por espaço e por fêmeas, alto investimento em número de ovos e com evidência de transporte simultâneo do maior número de girinos no gênero. O tamanho do território foi o principal determinante do sucesso de acasalamento dos machos e este fator não teve relação com os demais atributos testados. As fêmeas parecem acessar o tamanho do território do macho por meio do processo de corte que antecede a oviposição, momento em que o macho conduz a fêmea pelo território. O cuidado parental em Allobates paleovarzensis é realizado exclusivamente pelo pai, sem nenhuma evidência de participação materna. O macho cuida da prole durante todo o período de desenvolvimento em que esta se encontra associada ao seu território, de ovo até a fase de girino transportado para um corpo d’água. Na ausência do pai, a mortalidade da prole é elevada em todas as fases de desenvolvimento.

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Stress is ubiquitous for all organisms, however, impacts vary depending on type and strength of the stressor, as well as the organism’s tolerance. Currently, ionizing radiation is described by the “linear no threshold” model. However, considerable research suggests that a hormetic or threshold model may better describe radiation exposure. Using male house crickets the impacts of early-life radiation on life history and reproductive traits, molecular biomarkers, and trans-generational impacts were analyzed. Generally, radiation impacts were best described by non-linear modelling. Multiple aspects of sexual signalling were disrupted by radiation, and impacts emerged in F1 offspring through extended longevity and superior survivorship. / Thesis / Master of Science (MSc)

Background: Understanding of child development is predominantly based on maternal influences on children’s emotional, behavioural and cognitive outcomes. Although there has been an increase in research focus on fathers in recent years suggesting that fathers are important in the development of their child, there is still a shortage of research on fathers in the literature. Research has shown fathers negatively impact on their children’s emotional, behavioural and cognitive development, but there is a lack of understanding regarding the specific mechanisms through which paternal depression influences their children. The aim of the current PhD is to address this gap in the literature and this is done by: a) investigating the prevalence of depressive symptoms among fathers of children (aged 9 months – 7 years) and their associated risk factors; b) investigating the association between paternal depressive symptoms and different aspects of parenting such as warmth, conflict and involvement; c) testing whether fathers’ parenting mediated any association between paternal depressive symptoms and children’s emotional, behavioural and cognitive outcomes; and d) investigating the association between paternal depression/depressive symptoms and insecure father-child attachment. Methods: There are two methods employed for this PhD. One is secondary data analysis of the large and representative Millennium Cohort Study (MCS) (investigating a, b and c) and the other is primary data analysis of the Fathers-in-Focus (FIF) study using interview and observational methods to investigate (d). Results: Paternal depressive symptoms peak during the first year of children’s lives and then gradually decline between the first year and 7 years old (a). These depressive symptoms across the first 7 years of fatherhood were consistently associated with maternal depressive symptoms, relationship conflict and unemployment (a). Moreover, depressive symptoms in the first year were associated with father-child conflict, but not father-child warmth or involvement in parenting activities (b). Father-child conflict mediated the association between paternal depressive symptoms and children’s emotional and behavioural outcomes (c). Finally, father’s depressive symptoms were not associated with father-child attachment or children’s cognitive development (c and d). Conclusion: The key finding of this PhD is that father-child conflict is an important factor that may be associated with the risk transmission of paternal depressive symptoms and children’s emotional and behavioural outcomes. Therefore, it may be beneficial for service providers and clinicians to target interventions with depressed fathers’ and at-risk families.

Background: Becoming a parent can elicit many emotions. For some parents, it can be a time of anxiety and depression. Fathers are not exempt from this type of depression. Paternal depression (PD) is a serious health issue with long lasting consequences for both the father and child. Unfortunately, little research has been done on PD. The research that has been done recommends routine PD screening. Methods: A cross-sectional descriptive study design was used to determine the current PD screening practices and screening tools of providers in the Tucson area. The study sample consisted of randomly selected healthcare providers. The total number of possible participants was eighty two. Participants were provided a 20 question survey to assess screening practices as well as the beliefs, attitudes, norms, and confidence of providers regarding PD screening. Results: The study found many providers routinely screen for maternal depression but few screen for PD. While providers did recognize the impact PD has on children, this belief was not enough to implement screening. Most providers were unsure if PD was serious or if PD screening and therapy were effective. Few providers had any training or education regarding PD and few were confident in their ability to screen for PD. Providers who felt confident in their ability to screen, acknowledge the USPTF recommendation for screening all adults for depression, and had positive beliefs/attitudes regarding PD screening were more likely to have incorporated screening into practice. Of those who do screen, the majority do not use a validated screening. Conclusions: Although research recommends PD screening, it has not been implemented into practice. Training and education regarding PD is also lacking. The next step in research is to implement interventions that improve screening practices among providers, increase provider confidence in screening, and increase provider's awareness about PD.

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Phodopus campbelli is a naturally biparental dwarf hamster with males so paternal they will act as midwives during the birth of their litter. The hormonal regulation of parental behaviour has been well established in many species. However, to date, no causal mechanism for the extensive paternal behaviour displayed by male P. campbelli has been discovered. Recently, activity at the progesterone receptor has been shown to inhibit infant-directed behaviour in male mice. Therefore, the first study in this thesis was carried out to determine if antagonism of the progesterone receptor (PR) would enhance infant-directed care behaviour in naïve P. campbelli males. Despite detectable serum progesterone concentration in males, PR antagonism did not alter progesterone concentration, nor did it alter infant-directed behaviour in males with antagonized PR in adulthood. A slight increase in the latency to retrieve a pup seen in males with antagonized PR during adolescence suggests that there may be a developmental effect of PR activity on infant-directed behaviour in adulthood. Neonatal male rats express high levels of PR in brain regions important for parental behaviour. Since hormones can act very early in life to organize adult behaviour, the second study was carried out to determine if progesterone acting much earlier than adolescence is important in the regulation of paternal behaviour in P. campbelli adulthood. Males were treated daily for the first week of life with transdermal progesterone, which increased neonatal serum progesterone concentration fivefold. Despite the significant increase in progesterone (and therefore presumably activity at the PR), male behaviour in three different stages of adulthood (sexually naïve, during the birth of the male’s first litter, and in new fatherhood) towards pups was not altered. Measures of paternal contribution such as pup weight throughout the lactational period were altered by progesterone treatment during the neonatal period, but litter quality was ultimately high in both groups. Therefore, activity at the PR in adulthood, puberty, or during the neonatal period does not inhibit paternal behaviour in the naturally biparental hamster, P. campbelli. Thus, progesterone and its receptor do not organizationally or activationally regulate paternal behaviour in P. campbelli. / Thesis (Master, Biology) -- Queen's University, 2009-09-04 13:23:18.733