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Reproduction failure as a counterstrategy against potential infanticide
Ivanková, Lucia ; Bartoš, Luděk (advisor) ; Adéla, Adéla (referee)
The domestic cat is along with the dog recently the most common and popular pet. Unlike the dog the cat kept her appearance and nature without major changes despite long years of domestication. She has been highly adaptive to extremely variable conditions.
Beeing a prolific species she breeds succesfully in wide range of enviromental conditions and in a large spectrum of climatic conditions from subarctic to tropical regions. She reproduces successfully in urban colonies in high density of thousands of cats per square kilometre as well as in arctic regions with the population density equal to one cat per square kilometre. Mating strategy varies from promiscuous behaviour, through polygyny/polyandry system, to monogamy.
The infanticide in felinae is a common reproductive strategy. Male kills dependent offspring sired by another male in order to hasten the female oestrus and to reproduce with her himself. In domestic cats the infanticide attracts long-lasting discussion. However, in reality reports on the incidence of infanticide has been scarce.
One of the possible female counter-strategies is pregnancy block, known as a Bruce effect. The mated female blocks the blastocyte implantation when facing the treath of possible infanticide to avoid waste of energy by delivering offspring with poor chance for survival. Based on the questionnaire survey we have estimated the possibility of reproduction failure in a situation of potential male infanticide. From data which we have obtained we could not yet check the advanced hypothesis due to lack of variation and very few recorded cases of reproduction failure. On the other hand, we have accumulated extended information of the cat reproduction. In the future we are planning to collect more data in order to be able to test properly the hypothesis.
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An effect of environmental factors on foetal development in mammals
Sedláčková, Lucie ; Bartoš, Luděk (advisor) ; Bučková, Katarína (referee)
The development of fetus begins with merging of male and female sex cells, of the sperm with the egg, and with the formation of zygote. This moment triggers a complex process of prenatal development, a period very sensitive to changes and adverse conditions in the mothers surroundings. Such circumstances may include poor nutrition, sudden changes in the mothers social environment, a high occurrence of predators, stressful experiences due to inadequate handling and many other factors. All of these are connected by a frequently spelled term - stress.
It is stress that causes excessive discharge of glucocorticoid hormones, for example cortisol. This glucocorticoid is necessary for fetal growth and for induction of certain enzymes, such as lung surfactants. Under certain conditions, maternal cortisol can reach abnormal values. Consequently, the excess of cortisol impacts the fetus in high concentrations, which may negatively influence the growth of the fetus and its development.
In mammals, the mothers stress during her pregnancy not only increases her own cortisol levels, but also decreases the expression and activity of glucocorticoid barrier enzyme 11beta-HSD2 in the placenta; therefore, the fetus is less protected. On the other hand, this affects placental production and metabolism of other proteins and hormones sensitive to glucocorticoid, such as prostaglandins, progesterone, estrogens, glucose transporter and placental lactogen. Additionally, inhibition of 11beta-HSD2 by prenatal stress might contribute to low birth weight and to pregnancy diseases, such as premature birth.
Prenatal stress mainly affects brain development. The effects of prenatal stress in mammals have been observed with increased latency for games, indirect locomotion behavior, anxiety and impaired memory. Prenatal stress is also associated with greater volatility and attention disorders, which are also connected with a reduced learning ability. It has been ascertained that prenatally stressed individuals may exhibit increased aggressive behavior, demasculinized and feminized behavior has been observed in males.
The effects of prenatal stress are transmissible to the next generation and there is evidence that these are manifested to a greater extent in the following generations.
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Role of laterality in agonistic behaviour of red deer II
Jirsová, Adéla ; Bartoš, Luděk (advisor) ; Kouba, Marek (referee)
The theoretical part of this diploma thesis deals with the role of brain laterality of red deer (Cervus elaphus) in agonistic behaviour. Therefore, the largest part of the review of published scientific outcome is devoted to the agonistic behaviour, namely it focuses on the fights between males during the autumn rut. Battles are strictly ritualized and males adhere to strict rules. The role of laterality in animals is being recently studied and the outcomes so far indicates that, particularly in agonistic interactions the laterality may play a significant role. Brain lateralization is simply a preference for one or the other hemisphere in certain activities. The main topic of this thesis is how laterality affects combat of red deer.
The research part took place in a deer-park Zátoň where the duels between stags in rut were recorded. We also used videos from farms Podlesko and Žalany and a deer-park Milešov. These records were processed in the program Noldus Observes, with emphasis placed on the facts which deer was the initiator of the fight and his position to opponent, or with which eye the opponent was perceived at the beginning, but also during the fight. Data were statistically evaluated in SAS software (version 9.4., SAS Institute Inc.). We observed a strong tendency that the winner also initiates the interaction. Chance, that the winner will be the initiator, was compared to recipient 15 times higher. Initiator estimates his option in the battle to win, so he does not let the duel quit before it comes to physical confrontation. Regardless of the character of the behaviour initiator approached his rival more likely on right eye. There was statistically significant demonstrated initiator access to the recipient from the right side in parallel walk as well as in direct physical engagement. As stags train fights during the whole year, so even in the rut are information processed by the left hemisphere, which controls the routine affairs. We can say, that the deer fights during the rut are so frequent, when applies the routine of using antlers as a weapons and therefore we observe right side preference.
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Fire Combustion Control System Based on Lambda Probe
Bartoš, Lukáš ; Tříska, Vít (referee) ; Šimek, Václav (advisor)
The bachelors thesis deals with a design of automatic regulation of biomass combustion in fireplaces by lambda probe. The probe measures residual amount of oxygen during the combustion and the measured value influences the efficiency of combustion process and harmful emissions which are emitted into the air. The first part of the thesis is focused onto a theoretical analysis of the proces of combustion and the effects which influence efficiency and emissions. The second part concerns the description and the use of necessary components for automatical combustion regulation. The third part deals with a pratical test which confirms or declines the possibility of regulation by measurement of residual amount of oxygen. The fourth part follows up with a design of a regulation algorithm and its implementation. The fifth part evaluates past tests and suggests a procedure for production.
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Improvement of Manganese Separation in Drinking Water Treatment
Bartoš, Ladislav ; Janda, Václav (referee) ; Hlaváč, Jaroslav (referee) ; Dolejš, Petr (advisor)
The submitted paper covers manganese comprehensively. The introduction provides an overview of its basic physical and chemical properties. Its compounds are discussed individually, including their preparation, production, and practical uses. Furthermore, a list of analytical methods in which manganese is involved in the form of its compounds as reagents is included. The same section includes an overview of analytical methods whereby manganese and its compounds are detected, primarily in water industry processes. Attention is paid to manganese as a non-negligible constituent of the various parts of the environment. The section on manganese’s biogenic properties is interesting from the viewpoint of its toxicity as well as its role as an important biogenic element, indispensable primarily for mammals. The subsequent chapters discuss the various methods which are suitable, under specific conditions, for separation in the treatment of surface and underground water aimed at producing drinking, process, or industrial water, where a minimal concentration of this metal is required. The impact of the physical/chemical conditions which influence the efficiency of separation in a manner ranging from non-negligible to principal, is discussed further on. Given the specifics of treatment of surface [and] underground water, the chapters provide more details on the processes suitable for specific types of matrix and specific conditions. Next chapters sum up many years of the author’s observations and experiences in the various parts of the water management system, from the raw water source to treatment to distribution, focusing on surface and underground water separately. Last chapter describes the construction of a water treatment plant model, its launch and calibration, and the tests focused on separating manganese by way of coagulation using aluminium and iron sulphate.
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Analysis of menu cards at choice primary school from aspect of advised nutritional doses
BARTOŠ, Ladislav
Diploma thesis is based on the research which was carried out at the Primary school Velešín in the school year 2007/2008 and was focused on the pupils of fifth, seventh and ninth grades. The objective of the thesis was the analysis of the menus to find out saturation by macro-nutrients and selected micro-nutrients according to the nutritional requirements for school children. Research investigation might be divided into four parts. First part lied in the collection of the menus for the school year, their analysis in the programme NutriDan and following comparison to the norm of need of a school lunch, which is 35 % of a total daily nutritional dose. In the second part the variety of menus was assessed on the basis of repetition rate of particular meals in the school canteen in a month. The third part was the carrying out a questionnaire research of eating habits in pupils. In the fourth part the testing hypotheses were statistically assessed by means of chi-square distribution test. Out of gained results it was found out that required energy was fulfilled only in girls of ninth grade. The fulfilment was at the level 36.14{--}38.29 % of recommended daily dose (RDD). In other grades the energy was undervalued. Proteins were over the limit through the whole year. In the pupils of the fifth grade the fulfilment was in the interval 72.66{--}98.24 % of RDD (the average was 84.7 %), in the pupils of the seventh grade in the interval 55.28{--}74.22 % of RDD (the average was 64.2 %) and in the pupils of ninth grade in the interval 64.93{--}103.15 % of RDD (the average was 82 %). The fulfilment of carbohydrates was insufficient. In the fifth grade it was in the interval 18.81{--}25.35 % of RDD, in the seventh grade only in the interval 16.27{--}23.52 % of RDD and in ninth grade in the interval 21.54{--}29 % of RDD. The intake of lipids was excessive in the girls of the ninth grade (37.56{--}46.21 % of RDD). The fibre was in the norm of need. Out of the observed micronutrients calcium was deficient; the fulfilment was not over 21.62 % of RDD in the pupils of the fifth grade, in the pupils of the seventh grade 19.82 % of RDD. In the pupils of the ninth grade the fulfilment was in the interval 21.37{--}27.86 % of RDD. Through the whole year, vitamins B6 and B12 were over the limit. By the assessment of variety the low rates of leguminous soups, fish, fruit and vegetables were found out. Pork meat and sweet meals were excessive in several months. In boys increasing trend of Body Mass Index (BMI) depending on their age was evident; with higher age more respondents left out breakfast and had lunch more off the school canteen, which might be one of the causes of overweight or obesity in children. The consumption of fruit and vegetables was insufficient. Tested hypotheses proved the following: physical activity did not depend on respondents{\crq} sex; respondents{\crq} BMI depended on regular consumption of breakfast, time spent at a TV set and a computer did not depend on the age of respondents.
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