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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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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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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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Comparison of situation of mothers and fathers looking after children in frame of "equal parenting" in CZ
Taševská, Ivana ; Pavlík, Petr (advisor) ; Maříková, Hana (referee)
1 UNIVERZITA KARLOVA V PRAZE FAKULTA HUMANITNÍCH STUDIÍ Katedra genderových studií IVANA TAŠEVSKÁ Porovnání situace matek a otců pečujících o děti formou střídavé péče v České republice Diplomová práce Vedoucí práce: Ing. Petr Pavlík, Ph.D. PRAHA 2011 2 ABSTRACT Split-up of family is not a gender-neutral phenomenon. In most cases, children are confided to the care of mother after the split-up. The family law recognizes also other forms of care, but both joint-custody parenting is rarely used in the Czech Republic. However, there is a tendency to change the state affairs in recent years. Supporters and opponents of joint custody voice their arguments in the public sphere, but relatively little attention has been paid so far to those who are supposed practice joint custody parenting, the parents. That is why, the focus of my research has been a comparison of experience of mothers and fathers practicing joint custody of their children in the Czech Republic. Concretely, I wanted to study whether, similarly with foreign studies, the mothers and the fathers experience joint custody differently. For example, whether the fathers have received a bigger support from their family and friends than have the mothers and whether the fathers experience less financial stress than the mothers. My research is explorative...
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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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