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Nutritional biology of synanthropic mites (Acari: Acaridida)
Erban, Tomáš ; Smrž, Jaroslav (advisor) ; Grubhoffer, Libor (referee) ; Šustr, Vladimír (referee)
Ph.D. THESIS TITLE Nutritional Biology of Synanthropic Mites (Acari: Acaridida) ABSTRACT Several attempts to describe the nutritional biology of acaridid mites were undertaken, however full understanding of these processes remains incomplete. The objective of this Ph.D. thesis was to expand our knowledge concerning digestive physiology of stored product and house dust mites and to apply this knowledge to their nutritional biology. The research approach adopted in this Ph.D. thesis includes in vitro characterization of enzymatic activity in whole mite extracts (WME) and spent growth medium extracts (SGME), evaluation of the enzyme activities with respect to the gut physiological pH, enzyme inhibition experiments, in vivo localization of enzyme activities in the mite gut, determination of effects of nutrient or antifeedant additives in experimental diets on mite population growth and determination of the feeding preferences of synanthropic mites as assessed by in vitro and in vivo analyses. The gut contents of twelve species of synanthropic acaridid mites were determined to be within a pH range of 4 to 7 and showed a pH gradient from the anterior to the posterior midgut. The pH in digestive tract of synanthropic acaridid mites corresponds to the activity of proteases, α-glucosidases, α-amylases and...
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Digestive proteases of termites
Čermáková, Markéta ; Konvalinka, Jan (advisor) ; Ryšlavá, Helena (referee)
Digestive proteolysis in termites has not been studied yet. In this diploma thesis, proteolytic enzymes of the digestive tract of two significant pest species Reticulitermes santonensis and Coptotermes formosanus (Rhinotermitidae) were analyzed. Proteases were identified and quantified in gut compartments using a panel of specific substrates and inhibitors. Major proteases were localized in the midgut and were classified as endogenous serine proteases of trypsin type. Minor cysteine proteases were detected in the paunch and were most likely produced by symbionts. The trypsin protease from R. santonensis was chromatographically isolated and its N-terminal sequence was identified. The physiological importance of the digestive trypsin proteases was demonstrated using selective inhibitors tested in vivo with C. formosanus. Based on the analysis of proteases from additional 12 termite species, a general scheme of digestive proteolysis in the order Isoptera was proposed. (In Czech)
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Výživa a krmení zakrslých králíků
Halouzková, Soňa
This bachelor thesis on the topic Nutrition and feeding dwarf rabbits I focused on general information about dwarf rabbits as zoological classification, history breeding and use of dwarf rabbits. Much of the work deals with the anatomy, physiology of digestion and absorption of nutrients, which is closely related to nutritional requirements. Further chapters relate directly to nutrition and feeding techniques. I dealt with the general characteristics of nutrients, methods of their determination and the need for individual rabbits categories. Then I said feed mainly suitable for dwarf rabbits and basic principles of feeding. All nutrient standards are established only for domestic rabbits, that's why I said in the last chapter experiment aimed at comparing nutrition claims in domestic and dwarf rabbits. The experimental part involves the preparation of feed mixtures, which I fed my own breeding dwarf rabbits, familiarity with local conditions and tested rabbits and the results of the experiment.
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Factors regulating the expression and activity of digestive enzymes in the tick \kur{Ixodes ricinus}
KONVIČKOVÁ, Jitka
The intracellular proteolysis of ingested meal plays an essential role in tick development. The thesis focuses on the factors influencing the expressions and activities of digestive enzymes in Ixodes ricinus females during the feeding and post-feeding period. We have revealed the effect of fertilization on blood feeding and digestion. The females cannot reach the rapid engorgement phase without being fertilized. The rate of mated females in the nature proved the presumption that mating can occur even off the host. Implementation of in vitro feeding technique further extended our current knowledge about tick digestive apparatus. Adult females were fed on hemoglobin-rich and hemoglobin-poor diet and the mRNA expression levels of digestive proteases were determined. In line with obtained data, we assumed that albuminolysis is conducted by the same or similar pathway as hemoglobinolysis. The gene silencing method and protein immuno-detection were used to unequivocally identify the isoforms of 'early expressed' IrCL1 and 'late expressed' IrCL3 isoform of cathepsin L.
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Stanovení stravitelnosti organické hmoty metodou „in vitro" u píce odebrané z obnovených travních porostů v průběhu nárůstu 1. seče
Němcová, Petra
My thesis is focused on possible improvement of prediction of net energy lactation (NEL) and net energy fattening (NEV) concentrations by organic matter digestibility (OMD) which is determined by the laboratory method ELOS suitable for routine operations. This should improve current practice when the determination coefficients are taken from the stock-feeding tables. This method of OMD in vitro determination with ANKOM DaisyII Incubator allows serial digestion of more samples in one batch in the fermentation vessel en bloc which significantly decreases laboriousness of operation, filtration is not necessary anymore, and alternatively inoculum can be chosen according to the laboratory potential (rumen juice -- buffer, resp. clean cellulases). Prediction accuracy, when the cellulase preparations made in the Czech Republic with balanced cellulolytic and other activities were used in this experiment, proved to be sufficiently accurate and fully applicable for practical use within a wide range of grass samples. The accuracy of determination of OMD in vitro by ELOS method within values usual for grasses in technical maturity (grazing, conservation), i.e. 60 -- 80, demonstrates results which are practically identical (+-2.43 OMD units) to the Tilley, Terry (1963) method. Specific differences in growth rhythm of 7 tested grasses were stated (P 0.01), and the difference in heading of the earliest grasses (Fl - Hy 'Hykor', FA 'Kora' -- table 5) and late grass (LP 'Kentaur' -- table 5) was 3 weeks. The OMD value decrease is in the average of species, 7 dates of sample collection, two sites and two harvest years 4.44 units, decrease of NEL and NEV values by 0.42 MJ.kg-1 dry matter per week.
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Dynamics of digestive enzymes in the gut of ticks \kur{Ixodes ricinus} during blood feeding on the host.
KONVIČKOVÁ, Jitka
Proteolysis of ingested blood proteins is a crucial physiological process in ticks. This thesis focuses on profiling of dynamics of digestive enzymes in the ticks Ixodes ricinus during the course of blood-feeding on the host and during digestive phase after detachment from the host. We have measured the activity of digestive peptidases (using specific fluorescent substrates and inhibitors). The enzyme activities were negligible at the early stage of bloodfeeding than increased dramatically towards the end of the feeding period and dropped down immediately after detachment from the host. The activity of most enzymes increased again during the digestive phase before oviposition of females or metamorphosis of nymphs. The protein level of each peptidase was confirmed by immunolocalization using Western blot analyses.
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