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Aktivita raka mramorovaného v závislosti na reprodukčním cyklu
MARKOVÁ, Kateřina
The aim of this thesis was to elaborate a literature review on the topic of crayfish activity, in particular their feeding activity and the use of shelters, including an emphasis on the role of sex and the reproductive cycle. I also focused on the characteristics of the marbled crayfish, Procambarus virginalis Lyko, 2017 and its usability as a model organism. The experimental part of the thesis focused on comparing three groups of female marbled crayfish (with ovulum, with glair glands and without ovulum). Experiments have been carried out using a method for ecological assessment of feeding behavior and predator-prey relationship in various prey densities in the form of larvae of buzzer midge Chironomus plumosus (Linnaeus, 1758) by functional response analysis and subsequently tested for the effect of shelter presence at uniform prey densities levels. In our experiment, all three groups of tested females showed a type II functional response typical of predators. The results indicate that females without ovulum have been the most active in terms of food collection in all cases, with a generally positive effect of the presence of shelter. Females with employed ovulum are generally less active in terms of consumption, processing and overall aktivity due to hormonal, physiological and consequently behavioural changes. Females with glair glands behaved similarly to females with ovulum in our experiments, being more cautious and less active than females without ovulum. This was probably due to their increased gonadosomatic index (GSI) and, conversely, their decreased hepatopankreas to total body weight ratio, which renders these females unable to physiologically ingest large amounts of submitted food. Female GSI decreases again after ovulation, nevertheless, even females with already employed ovulum did not consume more food, as females prefer safety at this stage of the reproductive cycle. They are less active, move more slowly, spend more time in a shelter, tend to their eggs, and thus cannot devote themselves fully to hunting and prey processing. Regarding its life strategy, the marbled crayfish is a generally suitable model organism for use in various areas of research, however, it is important to take into account its rapid life and reproductive cycle and adapt the conditions of the given experiments to this fact, as the parallel use of female marbled crayfish at various stages of the reproductive cycle can modulate results in terms of their activity. Certain differences in the presented results may also be due to the origin of the experimental animals, as with very few exceptions all performed experiments with marbled crayfish have been carried out using laboratory individuals. A number of conditions that change seasonally in nature have been kept constant in the laboratory. Therefore, it is important to keep in mind that in wild, crayfish are also exposed to both biotic (predation pressure of various species of fish, birds or mammals) and abiotic (changes in temperature and water chemistry) factors that can influence food activity. Nevertheless, we assume that the patterns observed here will also be valid for female crayfish living in the wild nature. However, the lack of similar experiments leading to the elucidation of female activity depending on the stage of the reproductive cycle provides a room to investigate other, not just crayfish species.
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Stravovací návyky adolescentů
Krys, Lukáš
The bachelor's thesis deals with the eating habits of adolescents in secondary schools with a focus on gastronomy. In the theoretical part, the basic concepts related to the topic are clarified - the period of adolescence, adolescent nutrition and components of nutrition, eating behavior and eating habits of adolescents. The theoretical work also describes the environment influencing the eating habits, physical activity of adolescents and their preferences in eating. The practical part is based on the quantitative method of a questionnaire survey, where the information obtained will be used to determine whether adolescents have correct or incorrect informations and habits in the area of proper eating.
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Selekce potravy bobrem evropským (Castor fiber) ve čtyřech ročních obdobích
Macháčková, Kateřina
This thesis deals with the evaluation of Eurasian beaver foraging in cultural landscapes. The theoretical part is devoted to the existing knowledge concerning the selection of food by beavers and the factors influencing it. In the practical part, a total of nine stomachs of hunted or dead beaver individuals from different seasons are evaluated by means of the volumetric method. The results indicate that the ratios of the major constituents change during the seasons. As expected, the woody component is represented in the winter months, while its composition varies during the growing season. In summer, among other things, the representation of field crops is interesting. In spring and autumn there are transitions between woody and green biomass.
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Možnosti zvýšení adaptability a prevence negativních změn v chování u násady jesetera sibiřského (Acipenser baerii)
KODRAS, Marek
The experiment was performed to assess the impact of a modification in feed technology in the intensive rearing of Siberian sturgeon (Acipenser baerii) on the fish behavior. Four feeding regimes were tested in three repetitions: surface feeding during the day (DFSF), surface feeding at night (NFSF), bottom feeding during the day (DFBF), bottom feeding at night (NFBF). Sturgeon behavior was recorded using a video system in experimental observation tank before the application of different feeding regimens at 48th days post-hatching (dph) and every 20 days therafter (68th, 88th and 108th dph). In addition, the effect of five and ten-day starvation on fish behavior was determinated. Five parameters were tested: the total time spent in the lowest 10 and 25 % of the observation tank, the total time spent in the uppermost 10 and 25 % of the observation tank and the total activity. The whole experiment including larval rearing lasted 100 days and videos were analyzed using MATLAB software. Statistical differences were observed among the tested groups during our experiment. Experimental group NFBF at 88th dph showed the highest spending time in the lowest 25 % of the tank. Furthermore, NFBF at 68th and 88th dph displayed the lowest spending time in the uppermost 25 % of tank (only NFSF was not significantly different from NFBF at 68th dph). No statistical differences were observed in the uppermost or the lowest 10 % of the tank after all-day videorecording. After starvation, some differences were observed among the groups, however no clear trend or continuity with the data obtained before the starvation were found. In conclusion, the tested group NFBF showed better preconditions for intensive rearing of sturgeons, which might be subsequently stocked in open waters due to the lowest movement in the uppermost part of the tank (68th and 88th dph) than other tested groups. This could increase survival of the fish in the wild due to lower predation risk.
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Potravní chování hlaváčovitých ryb v závislosti na komplexitě prostředí
KOVÁŘ, Petr
Round goby Neogobius melanostomus (Pallas, 1814) and western tubenose goby Proterorhinus semilunaris (Heckel, 1837) are two benthic fish species, which have recently expanded from their native ranges of Ponto-Caspian Region to Europe and North America. While the ecological impact of round goby is widely documented, western tubenose goby receives little attention and its effect on aquatic communities has not yet been quantified. The main aims of present B.Sc. thesis are assessment and comparison of ecological impact and feeding behavior of both alien predatory fish species upon larvae of common carp (Cyprinus carpio, Linnaeus, 1758). The feeding behavior was tested in three habitats with different complexities: sandy and rocky substratum and habitat with plant. Present experiments were accomplished using comparative functional response, which has been successfully applied in assessment and comparison of ecological impact of alien species and their feeding behavior. Interspecific comparison between round goby and western tubenose goby showed similar handling times in rocky substratum and in habitat with plant suggesting similar per capita ecological impact of both predators. Intraspecific comparison showed significantly lower handling time in rocky habitats compared to others, and hence the ecological impact of both predators in such environments could elevate. Both, round goby and western tubenose goby showed type II FR in all treatments. Our results highlight the importance of complex actions in management of biological invasions, as the elimination of invasive round goby can boost the population growth of another alien species, e.g. western tubenose goby, which was not considered invasive until that time.
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Vliv ročního období a fáze laktace na potravní chování holštýnských krav ve vybraném chovu
Sukhov, Oleg
The aim of this thesis was to evaluate changes in food behavior cows of Holstein cattle during the year and the stage of lactation in a selected breeding. Monitored behaviors were: feed intake, water intake, rest, standing (especially in the hallways), movement and defecation. Ethological observations cows in the barn covered the period of one calendar year (may -- december 2014). In every season there were two-hour monitoring. Speeches animals were recorded every 3 minutes to ethogram. Records of monitoring were subsequently entered into ethogram and processed according to conventional statistical methods in MS Excel. Take aim was to evaluate own results and then compare them with the opinions of the authors reported. The obtained results can be determined considerable variation in the behavior of cows, which were affected by the current season: In the summer, there were frequent cows standing in the corridors, boos and increased fluid intake. Subsequently, in relation to water intake appeared decrease in feed intake. Conversely, in the winter, an increased incidence of lying and feed intake (compared to the summer), it is even behavior components which have the greatest impact on milk production.
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Referential vocalization of primates
Rejlová, Markéta ; Nekovářová, Tereza (advisor) ; Petrásek, Tomáš (referee)
Some types of vocalization encode only the individual properties of vocalization individuals such as species, size, and its motivational state, but also inform about events and objects around. This vocalization is called "functional reference." Referential communication acoustically different from other kinds of vocalization, and is produced only in response to specific stimulus. Recipient responds to vocalizations indirect information in the same manner as if the present initiative. Aim of this work to summarize the current knowledge on the referential communication of primates, especially food and anti-predator type, including neurological mechanisms, gestures intermediate, referential signal and interspecies comparisons. Keywords: referential communication, vocalization, primates, anti-predator behavior, feeding behavior
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Hunting behaviour of the wild population of river otter (Lutra lutra) in conditions of the shallow river.
POJEROVÁ, Lucie
Eurasian otter belongs to the group of endangered species. Its decrease was caused by the decline of suitable biotopes and the pollution of waste water. The human activity is considered to be another important reason for its decrease. Eurasian otters were hunted for their fur and for the losses on fish population. Although the number of Eurasian otter has been increasing lately, it is still important to protect these carnivorous animals. This bachelor thesis deals with the issue of foraging behaviour of the wild population of Eurasian otter. The aim of the thesis is to demonstrate the problems of otter?s foraging behaviour in shallow river; mainly the technique of this type of hunting. It was found that in the shallow river of the Lužnice River, the otters prefer rather the hunt-type of ?patch fishing?, which is usual while hunting in deep water. This kind of hunt has different characteristic since the preys are fish which are active during the daytime, contrary to inactive preys known from deep water of lakes and sea coasts. In the Lužnice River there were observed male and female otters and juvenile individuals. There was also observed the number of diving sessions during hunting session, the number of dives and hunting success set by the number of successful diving sessions.
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