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The influence of maternal care on the development of the circadian clock during ontogeny
Straková, Lucie ; Sumová, Alena (advisor) ; Spišská, Veronika (referee)
This bachelor thesis focuses on the importance of maternal care in early ontogeny on the development of circadian rhythms and further physiological development. The central clock oscillator (SCN) is most strongly synchronized by the external environment through the rhythms of light and dark. However, during ontogeny, when the main and peripheral oscillators first develop, maternal signals are the main synchronizers for the offspring. Thus, integration between mother and offspring is fundamental to the proper synchronization of the developing offspring's circadian clock, and the mother, through her behavior, can negatively or positively influence its setting. Attention is therefore paid to breastfeeding as a nowadays neglected factor of motherhood that has a strong influence. The composition of breast milk has proven beneficial effects over artificial diets, and breastfeeding has benefits for the health and circadian rhythm of mothers and their offspring. Premature infants are exposed to artificial conditions and weaned from maternal care, similar to offspring in cross-foster experiments. The observation of these effects on the development of their circadian rhythms again only confirms the importance of maternal care. Key words: maternal care, circadian rhythms, ontogeny, breastfeeding
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Maternal effect in selected rodent species: positive and negative effect on offspring fitness
Malá, Jana ; Landová, Eva (advisor) ; Stopková, Romana (referee)
This work describes the most studied mechanisms which could be classified as maternal effects. Here I focus on the effects of body weight, health status, intestinal microflora and age of the mother in model rodent organisms. I also present factors such as the position of the young in the uterus, population density, stress and especially maternal care, which accompanies this entire work. Each of these mechanisms can positively or negatively influence offspring fitness, depending on specific environmental conditions. Maternal behaviour is presented here in the form of research, which documents both epigenetic and genetic influences acting on its final form. Maternal care as an element of maternal behaviour shows a different measure between individuals, indicated by the frequency of licking and cleaning offsprings. By evaluation of maternal care, we can find in laboratory populations two stable phenotypes of individuals with different behavioural manifestations in terms of sexual behaviour, stress reaction, aggression or cognitive abilities. The discussion critically evaluates whether maternal care really affects reproductive success and whether it can therefore be considered an adaptive mechanism. According to the available information, low maternal care appears to be a more beneficial strategy in...
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Pach vítězství: role feromonů v interakcích raků
MAREŠ, Josef
Analysis of communication, hierarchy, and role of pheromones in crayfish is an interesting area that constantly brings new knowledge and can help us understand some facts that may be valid not only for crayfish but also other crustaceans. In this work, it was therefore studied how the offspring of two females behave in a one tank. After the dominance establishment in females (after a series of contacts and fights), the offspring of preferred a dominant female only, regardless of if their own or a unfamiliar mother. The dominant female, that successfully fought the fights, collected juveniles by its active movement, and they followed its movements. The subordinate female accepted her position, tried to avoid contacts, and reduced its activity. The juveniles practically ignored the subordinate mother at this stage of the experiment. Within the diploma thesis, all set goals were achieved and the newly discovered facts may be an important part of further follow-up experiments. We were able to respond positively to all primary hypotheses when: 1 / Females of marbled crayfish in one tank always established a relationship of the dominant and subordinate one, 2 / marbled crayfish juveniles always chose only one mother in a common tank, and 3 / it was in all cases the dominant one. The results show that dominance (whether communicated chemically or by visual stimuli) is a more important factor for juvenile crayfish than the specific brood pheromeone of their mother. The results bring significant knowledge to the issue of the hierarchy of various chemical and visual signals in crayfish communication. Thus, certain communication signals seem to be superior to others. The "winner odours" are probably stronger than such a strong stimulus as the brood pheromone responsible for recognizing the offspring and the mother. On the other hand, it is not possible to rule out a possible effect of the unattractiveness of the subordinate mother. How the relationships among the subordinate female, dominant female and their offspring would develop in remains opened to further research hypotheses.
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Is longer maternal care always beneficial? The impact of a four-year paid parental leave
Bičáková, Alena ; Kalíšková, Klára
We study the impact of an extension of paid family leave from 3 to 4 years on child long-term outcomes. Using a difference-in-differences design and comparing the first-affected with the last-unaffected cohorts of children, we find that an additional year of maternal care at the age of 3, which primarily crowded out enrollment into public kindergartens, had an adverse effect for children of loweducated mothers on human capital investments and labor-market attachment in early adulthood. The affected children were 12 p.p. more likely not to be in education, employment, or training (NEET) at the age of 21-22. The impact on daughters was larger and driven by a lower probability of attending college and higher probability of home production. Sons of low-educated mothers, on the other hand, were less likely to be employed. The results suggest that exposure to formal childcare may be more beneficial than all-day maternal care at the age of 3, especially for children with a lower socio-economic background.
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Parental care of drug-dependent mothers
Burgrová, Kristýna ; Křížová, Eva (advisor) ; Mašková, Eva (referee)
This bachelor thesis named Parenthood of drug addicted mothers focuses on the relationship between drug addicted mother and her child. It explains the nature of parenthood, children rights, needs, difficulties and specific issues of drug addiction in motherhood. Legal background of child protection has briefly been outlined and the main obligations of social authorities introduced. The drug dependence of mothers has been identified as a fundamental problem in child care with the use of some examples based on an on-site experience from The Therapeutic community Karlov. A complex system of social services available to drug addicted mothers and their children existing in the Czech Republic has been presented. Keywords drug addiction, drug addicted mothers, maternity, family, therapeutic community, endangered children, addiction treatment, children's rights, services for drug addicts
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Effects of early-life stress on development of cognitive abilities
Lukavská, Markéta ; Landová, Eva (advisor) ; Svoboda, Jan (referee)
Stress is a major factor affecting both current and long-term performance of the organism to certain situations. Stress can hormonally influence some neuronal axis, particularly frontal lobe, hippocampus and amygdale, through the activation of HPA axis and its feedback. Changes in these regions of the brain during postnatal ontogeny can significantly affect individual behaviour and cognition. The mentioned effect of stress on cognitive functions is influenced, in particular, by the timing of the impact of stress due to postnatal ontogeny of the above mentioned regions of the brain. In addition to this timing is necessary to take into account a whole range of other factors such as predictability and the level of control above stress situations. A summary of all of these factors affects the specific impact on cognition of the individual will be a stressor. An acute or a long-term mild stress (i. e. sensory stimulation) increases the individual's cognitive abilities. On the contrary, too strong, non-predictable or uncontrollable stress has a negative effect on cognitive performance. Unfortunately, it is not easy to determine a reliable marker of the stress situation. In the postnatal period in mammals, we meet with the so-called hypo-responsive period which is characterized by stress resistance and...
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Variability of social behaviour in domestic and feral horses
ŠANDLOVÁ, Kateřina
This thesis is focused on social behaviour of horses living under feral, semi-feral and domestic conditions and its variability. This variability is represented mainly by variations in agonistic and friendly interactions among horses. Also the differences in reproductive behaviour and maternal care are included.
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Parental behaviour and its relationship to social and reproductive system in voles \kur{(Microtus, Arvicolinae)}
ELIÁŠOVÁ, Michaela
I examined parental behaviour of three vole species, the brandt{\crq}s vole (Microtus brandti), the common vole (M. arvalis) and the levant vole (M. guentheri) in laboratory conditions. Monogamous and highly social Brandt{\crq}s voles displayed high levels of parental and paternal care. However, mostly promiscuous and solitary common voles also exhibited an intensive parental care. In contrast, polygynous and social levant voles displayed very low levels of parental care. Males of both latter species engaged in parental activities but spent less time in contact with pups then females. These findings suggest that intensive parental care may be connected rather with the high growth rate a slower postnatal development of the species than with social or reproductive system.
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