Number of found documents: 1432
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Butterfly thermoregulation across habitats and climates
LAIRD-HOPKINS, Benita Carmen
2023 - English
Global warming, through rising temperatures and changing precipitation patterns, is placing major stress on species and ecosystems. Understanding how species respond to temperature and the mechanisms underpinning thermoregulation can help us predict which species are most vulnerable in the face of warming. In this thesis, I explore how butterflies across different habitats and climates thermoregulate and the mechanisms, including morphology and behaviour, underlaying thermoregulatory ability. Firstly, when comparing the buffering ability of neotropical and temperate butterflies I found that tropical butterflies were able to maintain more stable body temperatures than temperate butterflies, and this was likely driven by their morphology. I also found that temperate butterflies used postural means to raise their body temperature more than neotropical species, likely an adaptation to the cooler air temperatures they experience. Secondly, I showed the importance of butterflies' thermoregulatory abilities at the community level, by comparing thermoregulation of European butterflies across geographic regions and climatic zones. This study highlighted that behavioural thermoregulation, including the use of microclimates and postural means, drives regional differences in butterflies' thermoregulatory abilities. Finally, I utilised the Müllerian mimicry exhibited in Heliconius butterflies to untangle the contributions of morphology and phylogeny in butterfly thermoregulation, investigating thermal traits, including buffering ability, take-off temperature and heating rate. I found that morphology, not phylogeny, was the main driver of thermoregulation in these butterflies. Further, I investigated differences in the thermoregulatory ability of Heliconius butterflies from different habitats. I found that species from colder habitats were able to maintain a more stable body temperature and took off at a lower temperature than those from hotter habitats, suggesting there is local adaptation or acclimation in thermal traits. Overall, this work highlights that species have their own unique thermoregulatory abilities, as a result of the thermal environment they experience, and that thermoregulation is driven by morphology, behaviour and physiology. My findings have important consequences for predicting the impacts of climate change on ectotherms, by highlighting variation in thermal ability which makes some populations and species more vulnerable, while others more resilient. This thesis lays the groundwork for future studies comparing species' thermal traits across climates and habitats, increasing our understanding of how species cope with climate and land-use change. Keywords: Insects; ectotherms; Lepidoptera; butterflies; thermoregulation; ecophysiology; behaviour; microclimates; climate change; tropical regions Available in the Digital Repository of University of South Bohemia.
Butterfly thermoregulation across habitats and climates

Global warming, through rising temperatures and changing precipitation patterns, is placing major stress on species and ecosystems. Understanding how species respond to temperature and the mechanisms ...

LAIRD-HOPKINS, Benita Carmen
Jihočeská univerzita v Českých Budějovicích, 2023

Comparative Analysis of Silk Proteins and Discovery of Novel Sericin Gene in Lepidopteran Moths
WU, Bulah Chia-Hsiang
2023 - English
This thesis focuses on the silk components of the Mediterranean moth, Ephestia kuehniella, and the discovery of a novel silk gene, P150/ser6, in the silkworm, Bombyx mori. We analyzed and described the cocoon silk components in both species. In the first publication, we combined transcriptomic, genomic, and proteomic approaches to identify silk proteins in E. kuehniella. In the second publication, we described the discovery of gene P150/sericin6 in B. mori based on microsynteny analysis. Keywords: Ephestia kuehniella; Bombyx mori; Galleria mellonella; silk; fibroin; sericin; synteny; genomics; transcriptomics; proteomics Available in the Digital Repository of University of South Bohemia.
Comparative Analysis of Silk Proteins and Discovery of Novel Sericin Gene in Lepidopteran Moths

This thesis focuses on the silk components of the Mediterranean moth, Ephestia kuehniella, and the discovery of a novel silk gene, P150/ser6, in the silkworm, Bombyx mori. We analyzed and described ...

WU, Bulah Chia-Hsiang
Jihočeská univerzita v Českých Budějovicích, 2023

Ecology of Gemmatimonadota
MUJAKIĆ, Izabela
2023 - English
Phylum Gemmatimonadota is a common group present in many natural environments. Yet, this interesting bacterial group is rarely studied. Since its discovery 20 years ago, only six cultured species have been described. Abundances of Gemmatimonadota in various environments are usually low (<1%), with the exception of soils, where they are one of the more abundant phyla. Probably for this reason, at the onset of this work, most of the knowledge about Gemmatimonadota came from studies of soil environments, while information about their ecology in freshwater lakes was missing. An interesting discovery relating to the unexplored diversity of Gemmatimonadota in freshwaters was the isolation of the first phototrophic member of this group, Gemmatimonas phototrophica, which was cultured from a shallow freshwater lake. To learn more about the ecology of Gemmatimonadota in freshwaters, the main focus of this thesis was the analysis of their distribution and diversity in several freshwater lakes, with emphasis on presence of photoheterotrophic Gemmatimonadota. The potential ecological roles of this group, metabolic capabilities and general genomic characteristics have also been addressed, thereby allowing a broader scope comparison with Gemmatimonadota from other environments such as soil, marine waters, or wastewaters. Keywords: Gemmatimonadota; metagenome; Gemmatimonadetes; MAGs; anoxygenic phototrophs; aquatic bacteria; CARD-FISH; freshwater ecology Available in the Digital Repository of University of South Bohemia.
Ecology of Gemmatimonadota

Phylum Gemmatimonadota is a common group present in many natural environments. Yet, this interesting bacterial group is rarely studied. Since its discovery 20 years ago, only six cultured species have ...

MUJAKIĆ, Izabela
Jihočeská univerzita v Českých Budějovicích, 2023

Addressing sustainable development to food systems, an agrotourism implementation case study
GREMME, Thibaud
2023 - English
Keywords: Sustainable development Food systems Innovation Rural development Available in the Digital Repository of University of South Bohemia.
Addressing sustainable development to food systems, an agrotourism implementation case study

GREMME, Thibaud
Jihočeská univerzita v Českých Budějovicích, 2023

Multilingualism and interculturality in an international work environment or interregional projects and work environment
ŠKÁBOVÁ, Natálie
2023 - English
Cílem této diplomové práce je analyzovat a zhodnotit každodenní praxi a strategie řešení vícejazyčných a mezikulturních interakcí v rámci mezinárodních/meziregionálních projektů. Bude analyzováno používání projektové interní lingua franca a/nebo překladatelské postupy a přizpůsobení se různým kulturám v rámci jedné firmy. The aim of this thesis is to analyse and evaluate the daily practice and strategies of dealing with multilingual and intercultural interactions with international/interregional projects. In particular, the use of a project-internal lingua franca and/or translation practices and accommodations of various contributing cultures will be analysed. Keywords: projektový management; interkulturalita; mnohojazyčnost; komunikace; tým. kultura; vedení; výzvy; rozmanitost; virtualita Available in the Digital Repository of University of South Bohemia.
Multilingualism and interculturality in an international work environment or interregional projects and work environment

Cílem této diplomové práce je analyzovat a zhodnotit každodenní praxi a strategie řešení vícejazyčných a mezikulturních interakcí v rámci mezinárodních/meziregionálních projektů. Bude analyzováno ...

ŠKÁBOVÁ, Natálie
Jihočeská univerzita v Českých Budějovicích, 2023

An ethical evaluation of philanthropic strategies employed by charitable organisations operating in Mongu district of Western Zambia
MUTEMWA, David
2023 - English
This study has been prompted by the fact that very little is known about the ethical aspects and operating strategies of charitable organisations in Mongu district of Western Zambia despite an influx of such organisations in the area from pre-colonial times. The aim of the study is to evaluate the ethical aspects of philanthropic strategies employed by charitable organisations operating in Mongu. Within social work, which is the guiding framework of this study, evidence of results alone does not satisfy the ethical aspect because ethics in social work are mainly deontological in nature, which means that the end does not always justify the means. The study endeavours to contribute to the discourse of philanthropic social work and, especially, towards a model for evaluating ethical aspects of philanthropic strategies of charities from the unique context of the charitable organisations operating in Mongu district of Western Zambia, which will also inform praxis in other similar contexts. This study has been prompted by the fact that very little is known about the ethical aspects and operating strategies of charitable organisations in Mongu district of Western Zambia despite an influx of such organisations in the area from pre-colonial times. The aim of the study is to evaluate the ethical aspects of philanthropic strategies employed by charitable organisations operating in Mongu. Within social work, which is the guiding framework of this study, evidence of results alone does not satisfy the ethical aspect because ethics in social work are mainly deontological in nature, which means that the end does not always justify the means. The study endeavours to contribute to the discourse of philanthropic social work and, especially, towards a model for evaluating ethical aspects of philanthropic strategies of charities from the unique context of the charitable organisations operating in Mongu district of Western Zambia, which will also inform praxis in other similar contexts. Keywords: ethics; philanthropy; strategies; charitable organisations (NGO/s); Mongu; Zambia Available in the Digital Repository of University of South Bohemia.
An ethical evaluation of philanthropic strategies employed by charitable organisations operating in Mongu district of Western Zambia

This study has been prompted by the fact that very little is known about the ethical aspects and operating strategies of charitable organisations in Mongu district of Western Zambia despite an influx ...

MUTEMWA, David
Jihočeská univerzita v Českých Budějovicích, 2023

The nature and identity of apologetics in light of the calls of scripture and the Second Vatican Council
NICOLSON, Stuart
2023 - English
Apologetics in recent times has had for many a negative value, and the term 'apologetics' did not appear in the Second Vatican Council documents. However, by returning to the sources in Scripture and the Early Church, especially Peter's call (1Peter 3:15-16) for all faithful to be ready to respond when questioned or challenged about their faith, and to do so in a Christian manner, apologetics can be understood as far more original, ordinary, and organic than how it is often defined. It was originally an integral part of Christians speaking out about their faith, participating with the Logos. Through a Petrine lens, apologetical calls and content can be identified in 10 of the 16 Vatican II documents, including two clear paraphrases of Peter's call. This indicates a problem in how apologetics is identified and understood. Part 1 provides a working definition for Petrine apologetics in order to identify its development through Christian history. Part 2 present a brief and selective history of apologetics. Petrine apologetics is observed and explored in Scripture in Part 2a, including in Jesus' ministry and the first Church generations. In Part 2b it is shown how a second century apologetical turn, particularly through Justin Martyr, reinforced by Eusebius, and concretised by several later Early Church Fathers, narrowed apologetics into becoming elite, intellectual, and clerical - not for all the faithful but the few. The Mediaeval period (Part 2c) could have seen a return to more universal Petrine apologetics, especially through the Fourth Lateran Council, but weak dissemination of its teachings meant the opportunity was lost. After the Reformation, in Part 2d, Charles Borromeo's pastoral apologetics stands out, as well as a growing movement based upon credibility in the English-speaking sphere where apologetics was becoming part of organic engagement of Catholics in Protestant societies. Part 3 focuses on Vatican II. The entrenched Justinian approach in Catholic Europe eschewed engagement with others, leaving apologetics as overly catechetical. Balthasar identified and rejected the old paradigm and the main reform ideas, calling for a new approach: Love Alone Is Credible. Many conciliar apologetics themes are congruent with his reform call, and with Petrine apologetics. In addition to apologetical calls, Vatican II shows that apologetical preparation should be embedded in Christian education (Gravissimum Educationis 2) and how apologetically prepared faithful should engage with society (Apostolicam Actuositatem 1, 2, 11, 29, 31, etc.). But the Council's apologetics calls were not developed and apologetics was mostly replaced by fundamental theology, which has problematic features from Justinian apologetics and the reform ideas Balthasar rejected, and is not related to the apologetical calls of Peter or Vatican II. However, there has been an organic development of apologetics since the 1980s. In Part 4, the problematic current state of Catholic understanding in the ordinary faithful is evident in two recent surveys. It is necessary to respond to this. By reframing apologetics according to the original Petrine call and its Vatican II confirmation, a New Apologetics (NA) can be developed that emphasises Peter's elements of preparation, response, in a Christian manner, for all the faithful. The Petrine elements are unpacked in today's context and several distinctions are explored, including objective and subjective approaches, and the spectrum of evangelisation-apologetics-catechetics. Three 'voices' are shown to have particularly contributed so far to NA: William Levada, Robert Barron, and Peter Kreeft. All intellectual and two being clerics, they have the insight and ability to guide developments. Looking forwards, the two named conciliar texts are explored in how they can be unpacked for developing an embedded apologetics of preparation, response, in a Christian manner: original, organic, ordinary apologetics. Apologetics in recent times has had for many a negative value, and the term 'apologetics' did not appear in the Second Vatican Council documents. However, by returning to the sources in Scripture and the Early Church, especially Peter's call (1Peter 3:15-16) for all faithful to be ready to respond when questioned or challenged about their faith, and to do so in a Christian manner, apologetics can be understood as far more original, ordinary, and organic than how it is often defined. It was originally an integral part of Christians speaking out about their faith, participating with the Logos. Through a Petrine lens, apologetical calls and content can be identified in 10 of the 16 Vatican II documents, including two clear paraphrases of Peter's call. This indicates a problem in how apologetics is identified and understood. Part 1 provides a working definition for Petrine apologetics in order to identify its development through Christian history. Part 2 present a brief and selective history of apologetics. Petrine apologetics is observed and explored in Scripture in Part 2a, including in Jesus' ministry and the first Church generations. In Part 2b it is shown how a second century apologetical turn, particularly through Justin Martyr, reinforced by Eusebius, and concretised by several later Early Church Fathers, narrowed apologetics into becoming elite, intellectual, and clerical - not for all the faithful but the few. The Mediaeval period (Part 2c) could have seen a return to more universal Petrine apologetics, especially through the Fourth Lateran Council, but weak dissemination of its teachings meant the opportunity was lost. After the Reformation, in Part 2d, Charles Borromeo's pastoral apologetics stands out, as well as a growing movement based upon credibility in the English-speaking sphere where apologetics was becoming part of organic engagement of Catholics in Protestant societies. Part 3 focuses on Vatican II. The entrenched Justinian approach in Catholic Europe eschewed engagement with others, leaving apologetics as overly catechetical. Balthasar identified and rejected the old paradigm and the main reform ideas, calling for a new approach: Love Alone Is Credible. Many conciliar apologetics themes are congruent with his reform call, and with Petrine apologetics. In addition to apologetical calls, Vatican II shows that apologetical preparation should be embedded in Christian education (Gravissimum Educationis 2) and how apologetically prepared faithful should engage with society (Apostolicam Actuositatem 1, 2, 11, 29, 31, etc.). But the Council's apologetics calls were not developed and apologetics was mostly replaced by fundamental theology, which has problematic features from Justinian apologetics and the reform ideas Balthasar rejected, and is not related to the apologetical calls of Peter or Vatican II. However, there has been an organic development of apologetics since the 1980s. In Part 4, the problematic current state of Catholic understanding in the ordinary faithful is evident in two recent surveys. It is necessary to respond to this. By reframing apologetics according to the original Petrine call and its Vatican II confirmation, a New Apologetics (NA) can be developed that emphasises Peter's elements of preparation, response, in a Christian manner, for all the faithful. The Petrine elements are unpacked in today's context and several distinctions are explored, including objective and subjective approaches, and the spectrum of evangelisation-apologetics-catechetics. Three 'voices' are shown to have particularly contributed so far to NA: William Levada, Robert Barron, and Peter Kreeft. All intellectual and two being clerics, they have the insight and ability to guide developments. Looking forwards, the two named conciliar texts are explored in how they can be unpacked for developing an embedded apologetics of preparation, response, in a Christian manner: original, organic, ordinary apologetics. Keywords: Apologetics; Apostolicam Actuositatem; Balthasar; Christian manner; Avery Dulles; Education; Engagement; Gravissimum Educationis; Justinian apologetics; Laity; New Apologetics; Ordinary apologetics; Organic apologetics; Original apologetics; Participation; Pastoral apologetics; Peter's call; Petrine apologetics; Practical apologetics; Preparation; Reframing; Response; Ressourcement; Second Vatican Council Available in the Digital Repository of University of South Bohemia.
The nature and identity of apologetics in light of the calls of scripture and the Second Vatican Council

Apologetics in recent times has had for many a negative value, and the term 'apologetics' did not appear in the Second Vatican Council documents. However, by returning to the sources in Scripture and ...

NICOLSON, Stuart
Jihočeská univerzita v Českých Budějovicích, 2023

Buněčné a molekulární charakteristiky hemolymfy u raků
KIFAYATULLAH, NA
2023 - English
Celulární a molekulární složky hemolymfy jsou hlavní součástí vrozeného imunitního systému u desetinožců. Hlubší znalosti složek hemolymfy, včetně hemocytů a proteinů hemolymfy, mohou zlepšit naše chápání vrozené imunity u korýšů. Pro studium celulárních a molekulárních aspektů koagulace a fagocytózy jsme využili transmisní elektronovou mikroskopii a kvantitativní proteomiku. Kapitola 2 přehledně shrnuje celulární a molekulární parametry vrozeného imunitního systému a účinky environmentálních stresorů a jejich abiotických a biotických stresových mechanismů u desetinožců. Vrozený imunitní systém desetinožců se silně opírá o hemocyty. Obecně jsou přijímány tři typy hemocytů na základě jejich morfologie, avšak stále existuje nedostatek shody ohledně klasifikace typů hemocytů. Klíčové funkce vrozené imunity, jako jsou koagulace a fagocytóza, jsou stále špatně pochopeny a vyžadují další zkoumání zejména na molekulární úrovni. Environmentální stresory mohou negativně ovlivnit imunitní odpovědi desetinožců, čímž zvyšují jejich náchylnost k nemocem. Avšak abiotický stresový mechanismus je špatně pochopen kvůli nedostatku dostupné literatury a vyžaduje další zkoumání. V kapitole 3 byla transmisní elektronová mikroskopie použita k prozkoumání ultrastrukturního chování hemocytů během koagulace a fagocytózy v raných stadiích zranění amputace nohy u raka mramorovaného Procambarus virginalis. Granulární hemocyty byly aktivovány jako první a morfologie cytoplazmatických granulí se změnila z elektronově hustých na elektronově průsvitné formy v expanzivním způsobu. Transformované granule obsahující amorfní elektronově průsvitné materiály se sloučily a vypustily svůj obsah do extracelulárního prostoru pro koagulaci. Pozorovali jsme, že zbývající jádro z degranulovaných hemocytů se podílí na procesu koagulace, což by mohlo být v některých předchozích studiích zaměněno s hyalinocyty. Kromě toho amputace nohy způsobila masivní degeneraci svalů, následovanou významným přílivem fagocytických hemocytů, které odstranily značné množství svalových vláken a organel, jako jsou mitochondrie, generované z rozpadajících se a rozkládajících se svalů. Dále jsme zjistili, že fagocytické hemocyty obsahují různé počty granulí v cytoplazmě a poprvé jsme objevili, že tyto buňky začleňují nekrotická tělíska vzniklá z degenerovaných svalů do svých organel, jako jsou cytoplazmatické granule a jádro. Granulární hemocyty byly nalezeny jako hlavní buňky provádějící fagocytickou aktivitu na místě zranění. Tato studie poskytuje poprvé komplexní popis všech stadií morfologických změn hemocytů během koagulace a fagocytózy po zranění u raků. V kapitole 4 proteomická analýza sražených a nesražených vzorků ukázala, že množství většiny proteinů zůstalo během koagulačního procesu nezměněno, což naznačuje, že nezbytné proteiny pro koagulaci jsou předem syntetizovány a uloženy před vznikem sraženiny. Díky svému otevřenému oběhovému systému mají desetinožci robustní koagulační mechanismy. Po zranění jsou uvolněny předem syntetizované koagulační faktory, což vede ke vzniku sraženiny. Proto byly pouze některé proteiny, jako jsou proteiny obsahující domény C-typu lektinu, laminin A řetězec a tropomyosin, během srážení sníženy, což naznačuje jejich možné role ve strukturní integritě buněk. Jejich snížení by mohlo usnadnit degranulaci, klíčový krok pro vznik sraženiny. The cellular and molecular components of the hemolymph are the major arm of the innate immune system in decapod crustaceans. In-depth knowledge of the hemolymph components, including hemocytes and hemolymph proteins, can enhance our understanding of innate immunity in crustaceans. We utilized transmission electron microscopy and quantitative proteomics to study the cellular and molecular aspects of coagulation and phagocytosis in the hemolymph. Chapter 2 reviews the cellular and molecular parameters of the innate immune system and the effects of environmental stressors and their abiotic and biotic stress mechanisms in decapod crustaceans. The innate immune system of decapod crustaceans heavily relies on hemocytes in the circulating hemolymph. Generally, three types of hemocytes are accepted based on their morphology, however, there is still a lack of consensus among researchers regarding the classification of hemocyte types. The key innate immune functions such as coagulation and phagocytosis are still poorly understood and require further investigation especially at a molecular level. Environmental stressors can adversely affect the immune responses of decapod crustaceans, increasing their susceptibility to diseases. However, the abiotic stress mechanism is poorly understood due to the lack of available literature and needs further investigation. In Chapter 3, transmission electron microscopy was used to investigate the ultrastructural behavior of hemocytes during coagulation and phagocytosis in the early stages of leg amputation injury in marbled crayfish Procambarus virginalis. The granular hemocytes were the first to be activated, and the morphology of cytoplasmic granules changed from electron-dense to electron-lucent forms in an expanding manner. The transformed granules containing amorphous electron-lucent materials merged and discharged their contents into the extracellular space for coagulation. We observed that the leftover nucleus from degranulated hemocytes participates in the process of coagulation, which could be confused with hyalinocytes in some previous studies. In addition, leg amputation caused massive muscle degeneration, followed by a significant influx of phagocytic hemocytes that removed a substantial amount of muscle fibers and organelles, such as mitochondria, generated from disintegrating and decaying muscle. Furthermore, we found that phagocytic hemocytes contained varying numbers of granules in their cytoplasm and, for the first time, discovered that these cells incorporate necrotic bodies resulting from degenerated muscles into their organelles, such as cytoplasmic granules and nucleus. The granular hemocytes were found to be the main cells that carry out phagocytic activity in the injury site. This study provides a comprehensive description of all the stages of morphological changes in hemocytes during coagulation and phagocytosis after injury in crayfish for the first time. In Chapter 4, proteomic analysis of non-clotted and clotted samples indicated that quantities of most proteins remained unchanged during the coagulation process, suggesting that necessary proteins for coagulation are pre-synthesized and stored before clot formation. Due to their open circulatory system, decapod crustaceans possess robust clotting mechanisms. Upon injury, pre-synthesized clotting factors are released, resulting in clot formation. Therefore, only a few proteins, such as C-type lectin domain-containing proteins, Laminin A chain, and Tropomyosin, were down-regulated during clotting, suggesting their possible roles in the structural integrity of cells. Their downregulation could facilitate degranulation, a crucial step for clot formation. Keywords: Vrozená imunita; Srážení hemolymfy; Fagocytóza; Proteomika krevních sraženin Available in the Digital Repository of University of South Bohemia.
Buněčné a molekulární charakteristiky hemolymfy u raků

Celulární a molekulární složky hemolymfy jsou hlavní součástí vrozeného imunitního systému u desetinožců. Hlubší znalosti složek hemolymfy, včetně hemocytů a proteinů hemolymfy, mohou zlepšit naše ...

KIFAYATULLAH, NA
Jihočeská univerzita v Českých Budějovicích, 2023

Monitoring reakce raků na různé podněty: jsou raci dobrými bioindikátory?
MALINOVSKA, Viktoriia
2023 - English
Sladkovodní raci mají zásadní roli v potravním řetězci a při přenosu energie mezi trofickými úrovněmi, často působí jako klíčové druhy. Mezi bezobratlými jsou raci primárními druhy s ohledem na jejich velkou velikost a obecnou hojnost a biologickou rozmanitost. Raci patří k běžným modelovým organismům ve vědeckém výzkumu a jsou využíváni jako bioindikátory kvality vody v laboratorních i terénních studiích. Sladkovodní raci jsou v přímém ohrožení, zatímco čelí znečištěnému vodnímu prostředí, protože do přírodních vod se během roku dostává mnoho chemikálií. Studie ukázaly, že raci vykazují různé behaviorální a fyziologické změny v reakci na antropogenní kontaminanty. V Kapitole 2 bylo naším cílem vyhodnocení srdeční a lokomotorické reakce raka signálního Pacifastacus leniusculus na krátkodobou pulzní expozici environmentálně relevantním koncentracím tří pesticidů (metazachlor, terbuthylazin a thiacloprid). Ve srovnání s kontrolními skupinami, u raků vystavených metazachloru bylo pozorováno významné zvýšení srdeční frekvence a ujeté vzdálenosti. Ve skupinách vystavených terbuthylazinu a thiaclopridu nebyly zaznamenané významné změny srdeční a pohybové aktivity raků. Protože většina raků v těchto skupinách nevykazovala lokomotorickou odezvu, nebyli zřejmě stimulováni k úniku z kontaminované oblasti. V přirozených podmínkách to může vést k trvalému vystavení environmentálním chemikáliím, které jsou potenciálně škodlivé. V Kapitole 3 jsme zkoumali účinky UV filtrů kyseliny benzoyl-4-hydroxy-2-methoxybenzensulfonové (BP4) a kyseliny 2-fenylbenzimidazol-5-sulfonové (PBSA) na raky během 30 minutové expozice. Jedinci raků exponovaní testovaným látkám se pohybovali na větší vzdálenosti a strávili více času v pohybu. V exponovaných skupinách byla také zaznamenaná vyšší frekvence srdečního tepu. Zaznamenané změny ve fyziologii a chovaní raků v obou studiích mohou být indikací potenciálního narušení schopnosti reagovat na predátory a následně ovlivnit početnost a funkční vlastnosti společenstev velkých bezobratlých. Spolu s využitím raků v laboratorních a venkovních experimentech existuje také možnost provést případovou studii s raky působícími jako bioindikátory. Hodnotili jsme fyziologické reakce raků na vodu dezinfikovanou oxidem chloričitým v dlouhodobém sledování za provozních podmínek v lokálním pivovaru (Kapitola 4). Narušení se projevovalo jako chaotické zvýšení a snížení srdečního tepu bez ohledu na denní dobu. V přirozeném prostředí je srdeční frekvence raků v noci vyšší s ohledem na noční aktivitu. Noční režim je důležitou adaptací pro raky a jeho narušení může vést k určitým rizikům souvisejícím se zvýšenou viditelností pro predátory a změnami při hledání potravy. Naše výsledky ukázaly, že raci vykazují srdeční a pohybové reakce, když jsou krátce vystaveni běžně používanému herbicidu metazachloru a dvěma široce používaným UV filtrům BP4 a PBSA, což naznačuje, že raci mohou potenciálně detekovat výskyt těchto vodních kontaminantů ve vodě. Prokázala se také užitečnost raka při dlouhodobém sledování kvality vody. Tato zjištění rozšiřují naše chápání používání raků jako bioindikátorů ve vědeckém výzkumu. Prezentovaná práce poskytuje data z laboratorních a případových studií zaměřených na srdeční a lokomotorickou aktivitu u raků. Vzhledem k tomu, že raci jsou základem potravního řetězce ve sladkovodním prostředí, je velmi důležité studovat účinky různých podnětů na takové klíčové druhy. Pochopení dalších biologických dopadů vodních polutantů na sladkovodní raky a další necílové taxony prospěje našim znalostem ohrožení funkčních změn složení populací a společenstev. Freshwater crayfish play a vital role in food webs and energy transfer between trophic levels, often acting as keystone species. Crayfish are prime species among invertebrates, considering their large size, abundance, and biodiversity. Crayfish belong to common model organisms in scientific research and have been used as bioindicators of water quality in laboratory and field studies. Freshwater crayfish are at direct risk while facing polluted aquatic environments, as many chemicals enter natural waters throughout the year. Studies have been shown that crayfish exhibit a variety of behavioral and physiological alterations in response to anthropogenic contaminants. In Chapter 2, we aimed to assess the cardiac and locomotor responses of crayfish Pacifastacus leniusculus to short-term pulse exposure to environmentally relevant concentrations of three pesticides (metazachlor, terbuthylazine, and thiacloprid). A significant increase in heart rate and distance moved was observed in metazachlor-exposed specimens compared to controls. We did not detect significant changes in crayfish cardiac and locomotor activity in terbuthylazine and thiacloprid groups. Most crayfish in these groups did not exhibit locomotor response, so they might not be stimulated to escape a contaminated area. This may lead to continuous exposure to environmental chemicals that are potentially harmful. In Chapter 3, we investigated the effects of UV filters Benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid (BP4) and 2-Phenylbenzimidazole-5-sulfonic acid (PBSA) on crayfish during 30 min exposure period. Specimens exposed to the tested compounds moved greater distances and spent more time in locomotion. Increased heart rate was also detected in treated groups. Such behavioral and physiological alterations of crayfish detected in both studies can potentially impair crayfish ability to respond to predators, and consequently affect abundance and the functional properties of macroinvertebrate communities. Along with use of crayfish in laboratory and field experiments, there is also an option to conduct case study with crayfish acting as bioindicators. We evaluated crayfish physiological responses to water disinfected with chlorine dioxide in long-term monitoring under operating conditions in local brewery (Chapter 4). The disruption of cardiac rhythmicity was detected with chaotic increases and decreases of heart rate regardless of the time of day. In natural environment, heart rate of crayfish is higher during night time considering nocturnal activity of these decapods. Nocturnalism is important adaptation for crayfish, and its impairment can lead to certain risks related to increased visibility to predators and alterations in foraging. Our results indicated that crayfish exhibit a cardiac and locomotor responses when shortly exposed to commonly used herbicide metazachlor and two widely applied UV filters BP4 and PBSA, suggesting that crayfish can potentially detect the appearance of these aquatic contaminants in water. The usefulness of crayfish in long-term monitoring of water quality have also been demonstrated. These findings expand our understanding of using crayfish as bioindicators in scientific research. In conclusion, this thesis provides the data from laboratory and case studies focusing on measurements of cardiac and locomotor endpoints in crayfish. Given that crayfish is at the base of the food chain in freshwater environments, it is of great importance to study the effects of different stimuli on such keystone species. Understanding further biological impacts of aquatic pollutants on freshwater crayfish and other non-target taxa will benefit our knowledge of threats to functional compositional changes in populations and communities. Keywords: Pesticidy; Pohyb; Sladkovodní korýš; Srdeční aktivita; UV filtry; Vodní polutanty Available in the Digital Repository of University of South Bohemia.
Monitoring reakce raků na různé podněty: jsou raci dobrými bioindikátory?

Sladkovodní raci mají zásadní roli v potravním řetězci a při přenosu energie mezi trofickými úrovněmi, často působí jako klíčové druhy. Mezi bezobratlými jsou raci primárními druhy s ohledem na jejich ...

MALINOVSKA, Viktoriia
Jihočeská univerzita v Českých Budějovicích, 2023

Účinky rostlinných produktů na růst, stravitelnost, složení těla, imunitní a stresovou reakci u ryb
ZARE, Mahyar
2023 - English
Očekává se, že v nadcházejících desetiletích bude akvakultura hrát zásadní roli při produkci potravin pro rostoucí lidskou populaci. Nicméně propuknutí nemocí může bránit dalšímu rozvoji tohoto odvětví. Jedním ze slibných řešení pro řešení tohoto problému je použití přírodních krmných aditiv, jako jsou rostlinné moučky a extrakty, které obsahují bioaktivní sloučeniny, včetně fenolických sloučenin, proteinů, vitamínů a minerálů. Bylo prokázáno, že tyto sloučeniny mají na ryby antistresové, antivirové, antibakteriální a antifungální účinky. Zatímco kopřiva byla rozsáhle studována v medicíně savců, její účinky na druhy využívané v akvakultuře nebyly dostatečně zdokumentovány. Nedávné studie však prokázaly pozitivní vliv kopřivy na růstovou výkonnost, hematologii, biochemii krve a imunitní systém ryb. Prášek z listů kopřivy v dávce 30 g/kg krmiva vedl k významnému zvýšení konečné hmotnosti ryb, hmotnostního přírůstku, procentuálního hmotnostního a specifické rychlosti růstu pstruha duhového. Přídavek moučky z listů kopřivy navíc zvýšil celkový obsah bílkovin a popelovin v těle ryb a zároveň snížil obsah tuku. Přídavek moučky z listů estragonu, v dávce 30 g/kg krmiva, významně zvýšil Hct% a počet leukocytů. Kombinace 10 g/kg moučky z listů kopřivy a 10 g/kg moučky z listů estragonu se projevila nejvyššími hladinámi erytrocytů a hemoglobinu. Moučka z listů kopřivy v dávce 30 g/kg krmiva, moučka z listů estragonu v množství 30 g/kg krmiva a kombinace moučky z listů kopřivy v dávce 10 g/kg a 10 g/kg moučky z listů estragonu v krmivu významně zvýšily hladiny albuminu v krevním séru. Moučka z listů estragonu v dávce 10 g/kg krmiva vykazovala nejvyšší aktivitu enzymu lysozymu v krevním séru ve srovnání s kontrolou. Hladiny celkového imunoglobulinu v krevním séru a celkového proteinu byly významně spojeny s použitím moučky z listů kopřivy v dávce 30 g/kg krmiva. Studie potvrzuje pozitivní účinky těchto aditiv na růstovou výkonnost, složení celého těla, imunologické, hematologické a vybrané biochemické faktory krevního séra. Různé úrovně česnekového prášku významně neovlivnily rychlost růstu a somatické indexy u okouna říčního. Přidání 30 g/kg česnekového prášku v krmivu však vedlo k výrazně vyšší hladině bílkovin v těle ryb. Použití jak dávky 10 g/kg krmiva, tak 30 g/kg krmného česnekového prášku se projevilo ve významně vyšší stravitelnosti tuku v porovnání s kontrolní skupinou a 20 g/kg krmivového česnekového prášku. Dieta obsahující 20 g/kg česnekového prášku vedla k významně vyššímu počtu erytrocytů a leukocytů. Kromě toho měly všechny skupiny s přídavkem česnekuvýznamně nižší hladiny cholesterolu v krevním séru ve srovnání s kontrolou. Česnekový prášek v dávce 30 g/kg zlepšil odolnost okouna říčního proti stresu z vysoké hustoty a manipulace, jakož to i jeho hematologické a imunologické parametry. Bezprostředně po stresu byla hladina kortizolu ve všech skupinách krmených česnekem významně vyšší než v kontrolní skupině a mezi skupinami nebyl žádný významný rozdíl v hladinách glukózy. Po 24 hodinách však byly hladiny kortizolu i glukózy významně nižší ve všech skupinách krmených česnekem ve srovnání s kontrolní skupinou. Tyto výsledky naznačují, že krmení okouna říčního dietou s česnekovým práškem může mít pozitivní vliv na zvládání stresové reakce. Česnekový prášek v množství 10 g/kg krmiva zlepšil stravitelnost tuků, obsah proteinu v těle ryb, hematologické parametry, imunologické parametry a odolnost při vysoké hustotě a manipulaci. Celkově lze česnekový prášek považovat za potenciální doplněk stravy pro zvládání stresu u okouna evropského, je však zapotřebí dalšího výzkumu, aby se určilo optimální dávkování a dlouhodobé účinky. Výsledky disertační práce naznačují, že používání přírodních krmných fytoaditiv by mohlo být potenciálním řešením pro řešení zdravotních problémů v akvakultuře, což povede k udržitelnější a efektivnější produkci potravin. The plant powders and extracts contain bioactive compounds, including phenolic compounds, proteins, vitamins, and minerals. These compounds have been shown to possess antistress, antiviral, antibacterial, and antifungal effects on fish. Nettle has been extensively studied in mammalian medicine, but its effects on aquaculture species have not been well documented. Recent studies have demonstrated the positive impact of nettle on the growth performance, hematology, blood biochemistry, immune system, and pathogens resistance of fish species. Nettle leaf powder at a rate of 30 g/kg feed, improved the final body weight (FBW), weight gain (WG), weight gain percent% (WG%), specific growth rate (SGR%), and increased whole-body proximate protein and ash content while reducing whole-body proximate fat rainbow trout (Oncorhynchus mykiss) fingerlings. Tarragon leaf powder at a rate of 30 g/kg feed, significantly increased the haematocrit% (Hct%) and leukocyte count. The combination of 10 g/kg feed nettle leaf powder and 10 g/kg feed tarragon leaf powder resulted in the highest levels of erythrocyte count and haemoglobin (Hb). Nettle leaf powder at 30 g/kg feed, tarragon leaf powder at 30 g/kg feed, and a combination of 10 g/kg feed nettle leaf powder and 10 g/kg feed tarragon leaf powder significantly increased albumin levels in blood serum. Tarragon leaf powder at 10 g/kg feed showed the highest blood serum lysozyme enzyme activity compared to the control. Blood serum total immunoglobulin and total protein levels were significantly associated with nettle leaf powder at 30 g/kg feed. The study confirms the positive effects of these additives on growth performance, whole body proximate composition, immunological, haematological, and selected blood serum biochemical factors. Different levels of garlic powder did not significantly affect growth performance and somatic indices in European perch (Perca fluviatilis). However, adding 30 g/kg feed garlic powder resulted in a significantly higher level of whole-body proximate protein. Both 10 g/kg feed and 30 g/kg feed garlic powder showed significantly higher fat digestibility than the control and 20 g/kg feed garlic powder groups. The 20 g/kg feed garlic powder diet resulted in significantly higher erythrocyte and leukocyte count. Furthermore, all garlic groups had significantly lower blood serum cholesterol levels compared to the control. Garlic powder at level 30 g/kg feed improved European perch's resistance against high density and net handling stress, as well as their haematological and immunological parameters. Immediately after stress, the level of cortisol in all garlic-fed groups was significantly higher than in the control group, and there was no significant difference in glucose levels among the groups. However, after 24 hours, the levels of both cortisol and glucose were lower in all garlic-fed groups compared to the control group significantly. Garlic powder at a level of 10 g/kg feed improved apparent fat digestibility, whole body proximate protein, hematological parameters, immunological parameters, and increased resistance in high density and net handling stress. Overall, garlic powder could be considered as a potential dietary supplement for managing stress in European perch, however, further research is needed to determine the optimal dosage and long-term effects. Results of present thesis suggest that the use of natural feed phyto-additives could be a potential solution to address health issues in aquaculture, leading to more sustainable and efficient food production. Keywords: Bioaktivní látky; konverzekrmiva; listové moučky; kortizol; hematologie; imunologie; myeloidní buňky; stres Available in the Digital Repository of University of South Bohemia.
Účinky rostlinných produktů na růst, stravitelnost, složení těla, imunitní a stresovou reakci u ryb

Očekává se, že v nadcházejících desetiletích bude akvakultura hrát zásadní roli při produkci potravin pro rostoucí lidskou populaci. Nicméně propuknutí nemocí může bránit dalšímu rozvoji tohoto ...

ZARE, Mahyar
Jihočeská univerzita v Českých Budějovicích, 2023

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