• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 23
  • 2
  • Tagged with
  • 25
  • 10
  • 6
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Vliv přikrmování upravenými krmnými komponenty v kapřích rybnících na kvalitu vody v recipientech

HLAVÁČ, David January 2015 (has links)
Minimisation of environmental impact is a key factor in insuring the long-term sustainability of the aquacultural industry. Numerous studies have examined nutritional strategies as a means of reducing waste production and minimising the environmental impact of aquacultural waste. To achieve this goal, it is the challenge to the aquacultural industry to develop "environmentally friendly" feeds, feed management and feed production methods to reduce pollution. This applies mainly to pond farming of common carp, which plays an important role in global aquaculture. The objective of this Ph.D. thesis was to evaluate the possibilities of using modified cereals in pond aquaculture. It focused on issues that contribute to a better understanding of the interconnection between fish production, feed quality and applied feeding technologies with respect to water quality, nutrient budget, quality and quantity of natural food.
12

Potravní enrichment u vybraných zástupců čeledi Felidae / Feeding enrichment in selected Felids

PINTOVÁ, Radka January 2014 (has links)
Environmental enrichment and welfare are important elements for animals in captivity. This study starts with general introduction in breeding animals in zoos and environmental enrichment for important taxonomic groups. The practical part is following with a research on effect of food on frequency of stereotypic behavior. The theoretical assumption says that the different time of eating the food leads to different behavior. Long-term observation was done to confirm the theory. Eight animals belonging in three species were observed in time of feeding, eight types of food were given. The behavior at the time of feeding and after was evaluated by ethogram. General trends in time used for feeding were confirmed (the shortest time for chicken and opposite the longest for head of a goat). The evaluation of stereotypic behavior mainly showed the individuality of each animal. However, servals exhibit most of this pattern. The relationship between stereotypes and time of feeding was insignificant. Generally most of the results were statistically insignificant because of low number of repetition in the dataset.
13

Individuální růst a variabilita časných preimaginálních stádií vodní ploštice bodule obecné (Ilyocoris cimicoides) (Heteroptera: Nepomorpha: Naucoridae) / Individual growth and variability of early development stage of creeping water bug Ilyocoris cimicoides (Heteroptera: Nepomorpha:Naucoridae)

PILAŘOVÁ, Simona January 2014 (has links)
This thesis investigates an influence of environmental variables (temperature and food availability) on development and growth of the first three nymphal stages of Ilyocoris cimicoides Linnaeus, 1758 Individuals were housed individually in experimental cages from eklosis into adulthood. Experiments were carried out in a combination of four different temperatures (17 ?, 19 ?, 22 ? and 25 ? C) and two different modes of food availability (full-fed every day, red-fed every other day) (in eight treatments). The temperature significantly influenced the length of nymphal development. According to our expectation, shortest development was achieved in individuals reared at 25° C. Development period was prolonged by decreasing temperatures. Unpredictably, the nymphs of the 3rd instar had longest development at the lowest temperatures (17 ? C) whereas nymphal development of the 1st and 2nd instars ran faster Both, the lowest- (17 ? C) as well as the highest used temperature (25 ? C) are probably very close to the temperature limits, that corresponds to the limits of postembryonic development. The optimum temperature for development was 22 ? C. Furthermore, it has been found that food availability should also significantly affect growth and development. Surprisingly, less mortality was observed in individuals reared in reduced feeding treatment, except the only case - nymphs reared in low temperature (19 ? C), where higher mortality was found in individuals reared at the same food availability.
14

Potrava dravých ryb v nově napouštěné nádrži Chabařovice / Food of predatory fish during the flooding of the Chabařovice coal mining pit

KABILKA, Petr January 2007 (has links)
The Chabařovice coal mining pit is currently still under the process of continuous flooding and its area increased up to 174 ha since 2001.Adult perch (Perca fluviatilis) have been the most numerous fish of the lake until 2004. Fish were collected during the ichtyological survey sampling campaigns in June and September.Diet composition was expressed as percent weight, which was calculated for each prey taxon.
15

Vliv potravy a krmení mláďat na jejich kvalitu u vrabce domácího (Passer domesticus) / Effects of diet and feeding behaviour on nestlings quality in House Sparrow (Passer domesticus)

Lusková, Miroslava January 2010 (has links)
This study focused on analysing the diet composition of nestlings of different age during two breeding seasons in rural environment of agricultural farm near Veselí nad Lužnicí, South Bohemia. Feeding behaviour and habitat selection by parents was also monitored. Population decline of the species as a consequence of low invertebrates rate in nestlings diet and disappearing of important habitats are discussed. Most of studies on feeding behaviour in the Czech Republic focused only on feeding frequency. Two commonly used methods for diet determination, neck- collars and faecal analysis, were compared. The feeding frequency of male and female were also determined. Coleoptera (Scarebeidae) were the most often determined group in samples of feacals, while Diptera (Tipulidae) were the most often determined group in samples from ligatures. The differences between diet of younger and older nestling were assessed. While diet of young nestlings contained Diptera, Coleoptera dominated in diet of older nestlings. The vegetable food, mainly seeds of Poaceae, dominated in diet of older nestlings. Amount of food increased along age gradient (samples of older nestlings were heavier). Different effect of animal proportion in the nestling diet was determined. Increase in animal proportion in the dietof young nestlings caused...
16

The reaction of phytophagous on differenced manganese content in the diet

Martinek, Petr January 2018 (has links)
The rapid adaptation of insect species on environment changes can represent a significant advantage for their development and consequently a great negative effect for the stability of forest ecosystems. Larval individuals of Cabera pusaria and Lymantria dispar and adults of Melolontha hippocastani and Phillobius arborator is in general widely expanded species of herbivorous insects in European regions and with them are connected huge economic and ecological losses. The composition of food (biogenic elements, trace elements, heavy metals, proteins, carbohydrates etc.) is the main parameter of food quality. Laboratory experiment with natural diet (assimilation apparatus of Quercus petraea and Betula pendula) in control conditions (temperature, humidity, and light) were used for determination of insects’ reactions to increased concentration of manganese in the diet. Food was contaminated by soaking in solutions of MnCl2.4H2O with graded manganese concentrations. On the base of experiment design and character of reared experimental species we determined the food consumption, the activity period of adults, the mortality of larvae, the quantity of eggs laying, the dry mass and live weight of experimental individuals, concentrations of manganese in unconsumed food, excrement and lyophilized bodies, larval and pupal exuviae. Mentioned parameters were observed for determination of reactions of experimental insect species on changed food quality via the presence of high manganese contents. The results showed, that the reactions of individual experimental animals were very different. We observed the negative reaction to high manganese content in the diet of L. dispar larvae with the tendency of its compensation (the increasing food consumption rate and prolongation of development). Caterpillars of C. pusaria were very sensitive to changed food quality and therefore we observed high mortality. On the other side, the high manganese content in the diet of P. arborator in the laboratory conditions influenced neither their food intake nor their mortality. For individuals of M. hippocastani very high content of manganese in the diet significantly influenced the food consumption and thereby their development(distortion of copulation and consequent eggs laying). We observed the repellent effect of high levels of manganese in the diet. In all cases, the elimination mechanisms of surplus manganese in the diet were observed. Individuals in experiments exuded manganese through the digestive system into excrements and by incorporation of it into unspecified parts of their adult body without direct physiology activity or in exuviae of caterpillars.
17

Ekologické faktory ovlivňující složení potravy kalouse ušatého Asio otus (Linnaeus, 1758) / Ecological Factors and their Impact on a Diet of the Long -eared Owl (Asio otus)

Gaďůrková, Kateřina January 2013 (has links)
My thesis deals with ecology and diet of the Long - eared Owl (Asio otus). The study area a wintering place is situated near the town of Kladno. 1) The hypothesis that a high snow cover has an influence on the Long-eared Owl diet has been confirmed. 3) The thesis deals with the determination methods of small vertebrate species in Long - eared Owl's diet. The work deals with postcranial skelet as well. There was compilled the method of the sex determination in Common vole (Microtus arvalis). The sex determination was based on the morphological differences of the pelvic bones. The results (sex ratio) had been statistically tested and as such found significant. 2) There were also analyzed the skeletal remnants of the pelvic bones in the pellets. The study of the pelvic bones was carry out in order to find expected seasonal changes in the sex ratio in a dominant prey Common vole (Microtus arvalis). That hypothesis was not confirmed. Keywords: Long-eared owl (Asio otus), diet, postcranial skeleton, pelvic bones
18

Monitoring invazního raka pruhovaného v ÚN Lipno a evaluace jeho predace vybranými druhy ryb / Monitoring of invasive spiny-cheek crayfish in Lipno dam and the evaluation of its predation on chosen fish species.

SALON, František January 2015 (has links)
Astacologic survey took place in ÚN Lipno and was conducted in time from 2012 till 2013. For the actual mapping of the occurrence of spiny-cheek crayfish, the locations of total 17 places were detected. These monitoring areas were carried out in two ways for collecting the samples. The trapping of all individuals was achieved with special instruments, like pots or traps by hands or with the help of nets. For the caught specimens of spiny-cheek crayfish, which were determined by sex, the length of carapace was measured and as well if possible, the postorbital carapace length was taken. Throughout the whole monitoring, 228 individuals of spiny-cheek crayfish were caught in the amount of 107 (47%) females (CL = 21.5 ? 7.3 mm) and 121 (53%) males (CL = 20.1 ? 5 mm). Another aim of this work was to demonstrate that crayfish figure in fish food menu. Catches of fish were carried out in two ways, using fishing rods or into the clutches. The stomachs and intestines contents were analyzed at caught fish samples. If the condition of the contents of stomachs or intestines were allowed, it was also identified, what kind of food it was. For our annual issues, were included mainly species of piscivor fish. Spiny-cheek crayfish were identified in the stomachs of two species of fish, namely perch and pike.
19

Vývoj, růst a variabilita jedinců semiakvatické ploštice hladinatky pobřežní (Microvelia reticulata) (Heteroptera: Gerromorpha: Veliidae) / Development, growth and variability of semiaquatic bug Microvelia reticulata (Heteroptera: Gerromorpha: Veliidae)

VOJTOVÁ, Lucie January 2012 (has links)
I investigated the effect of environmental factors (temperature and food availability) on the development and growth of semiaquatic bug Microvelia reticulata Burmeister, 1835. I focused on the developmental rate isomorphy. In a cross-designed experiment, M. reticulata was individually kept over whole juvenile period (eggs to reaching maturity) and subjected to treatments of three temperature (17, 21, 25 °C) and two food availability (full - daily feeding and reduced - 2 days interval) and their interaction. Development and growth was strongly influenced by temperature. Longest postembryonic development measured in individuals kept in the lowest temperature (54 days) contrasted to those kept in the highest temperature (16 days). Mortality was also significantly influenced by temperature; highest mortality rate was found in the 17 °C treatment. Effect of food availability was significant only in low temperature, resulting in the better survival of individuals on the high food level. In other temperature treatments, I found no effect of food on survival rate of M. reticulata. However, the food level influenced development significantly. In the 21 °C and 25 °C treatment, individuals on a full food developed faster than individuals on a reduced food. In 17 °C the food availability had no effect on time required to reach maturity. The best fitness (expressed as combination of low mortality rate and short development) was observed in 21 °C, both other temperature treatment were found stressing. Food availability had stronger effect on female individuals compared to males. In conclusion, I found no evidence of developmental rate isomorphy in M. reticulata. The research was supported by project of the Grant Agency of the Czech Republic GAČR P505/10/0096.
20

Využití mechanicky upravených krmiv v polointenzívním chovu tržního kapra / The Use of Mechanically Modified Cereals in Semi ? Intensive Culture of Market Carp

VODÁREK, Michal January 2011 (has links)
120 day feeding experiment was executed on the Trebon fishponds in the area of feeding the market carp. The aim was to determine what way of cereals processing will have favorable effects in terms of production efficiency in the mechanical processed cereal by grinding and mashing in comparison with cereal without processing. The theoretical part focuses on the characteristics of natural food, technology feeding, feed distribution and appropriate processing to achieve high growth results in common carp (Cyprinus carpio). The practical part includes the methodology and results of the production parameters of carp fed by triticale without processing, by grinding and mashing. The highest feed efficiency was observed in carps under supplementary by triticale mashed feeding with FCR 0.83; 1.21 kg of FCE and FCR / SGR; 1.05; the highest growth rate was achieved in carp under supplementary by grinded triticale (1,2 mm) feeding with SGR: 0.86 %.d-1.; worse results were observed in carp feeding by triticale without processing: FCR: 1.27; FCE: 0.79 kg; FCR / SGR: 1.61; SGR: 0.79 %.d-1.

Page generated in 0.0329 seconds