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The influence of carotenoids on fitness related traits in anurans : implications for ex situ conservationOgilvy, Victoria January 2011 (has links)
Amphibians are facing an extinction crisis, and in many cases it has become necessary to conserve species in captivity. Unfortunately, our understanding of the nutritional requirements of amphibians in captivity is currently limited. There have been anecdotal reports that captive bred amphibians have duller skin colouration than wild members of the same species. Many amphibians use carotenoid pigments in skin colouration. Carotenoids are yellow-red pigments synthesised by photosynthetic tissues, however vertebrates cannot synthesise them de novo and rely entirely on dietary sources. Reduced colour in captive bred amphibians could therefore result from limited carotenoid availability in the diet. Limited access to carotenoids could have further negative consequences on health and reproductive success since carotenoids are known to function in the immune, antioxidant and reproductive systems of other vertebrate taxa. The role of carotenoids in amphibian fitness is currently unknown, and the aim of this PhD was to assess the importance of carotenoids to anuran amphibians. Skin colour may be influenced by carotenoid availability, and it was therefore important to establish a suitable method for quantifying skin colour in amphibians. In Chapter 1 I assessed two methods for colour quantification, including digital photography and spectrometry. Neither method was significantly more accurate than the other, however I chose to use photography for my studies for reasons of practicality. In Chapters 2 and 3 I assessed the role of carotenoids in the reproductive systems of wild frogs. I found that carotenoid-based skin colouration was involved in the breeding behaviour of wild Agalychnis moreletii frogs. I found positive assortative mating by colour in that frogs were found mating with individuals with similar carotenoid-based colouration. This assortative mating by colour may be driven by mutual mate choice, or may have evolved to prevent mismatched pairing with a sympatric and phenotypically similar species (A. callidryas). I then analysed the carotenoid composition of eggs produced by wild A. moreletii and Phyllomedusa trinitatis, which are tree frogs with similar reproductive ecology but different egg deposition strategies: Agalychnis moreletii deposits green eggs on the surface of leaves while P. trinitatis wraps pale cream eggs in leaves. The concentration and diversity of carotenoids was significantly higher in A. moreletii than P. trinitatis and potential ecological explanations for this are discussed. In Chapter 4 I investigated carotenoid availability in the diet of captive amphibians by analysing the carotenoid composition of commonly used feeder-invertebrates. I assessed interspecific variation in carotenoid accumulation in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus), which were all fed one of three diets (wheat-bran, fish-food based diet, fresh fruit and vegetables). All three cricket species were a poor source of carotenoids unless they were gut-loaded on a carotenoid-rich diet. Nutrient retention over a two-day period was poor across species. Finally, there were significant interspecific differences in gut-loading capacity, with G. bimaculatus having the greatest capacity. This study shows that carotenoid availability to captive amphibians will be limited unless they are fed specific feeder invertebrate species, recently gut-loaded on carotenoid-rich foods. In Chapters 5, 6 and 7 I assessed the influence of carotenoids on fitness related traits in captive anurans. I firstly assessed colour degradation in captive-reared A. moreletii frogs and looked at whether skin colour could be improved through increased carotenoid availability in the diet. I found that carotenoid-based skin colour degraded quickly in captivity but could be improved through dietary supplementation with carotenoids, however there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Next, I investigated the effect of carotenoids on larval growth and development, and post-metamorphic growth, development, skin colour and reproductive success in captive A. callidryas frogs. I found no direct effect of carotenoids during larval stages, however there were carry-over effects on post-metamorphic growth and skin colour. Increased post-metamorphic carotenoid availability positively influenced growth, skin colour and reproductive success. Similarly to A. moreletii, there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Finally, I examined the protective potential of carotenoids in Silurana (Xenopus) tropicalis tadpoles that were exposed to ultraviolet (UV) light. Exposure to UV light significantly reduced tadpole survival and there was no evidence that carotenoids afforded any protection. Nevertheless, in tadpoles that were not exposed to enhanced UV light, carotenoids increased survival. Furthermore, carotenoids had a significantly positive effect on the developmental rate of tadpoles in both UV limited and UV enhanced environments. The studies in this PhD show that carotenoid availability has important consequences on fitness related traits in anuran amphibians, which include effects on growth, skin colour, reproductive success and survival. Carotenoid availability to captive amphibians will, however, be low unless they are provided with feeder invertebrates that have been recently gut-loaded on carotenoid-rich foods. These findings should be considered when recommendations are made on the nutritional requirements of amphibians in captivity as they could significantly improve the fitness of captive-bred individuals, and thus increase the success of ex situ conservation programmes.
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Evidence based ex situ husbandry for captive amphibiansMichaels, Christopher January 2015 (has links)
Amphibians are declining worldwide in response to pressures that are too numerous, difficult and rapid to ameliorate in the wild before some taxa become extinct. Ex situ conservation, whereby animals are maintained in captivity until threats in the wild have been resolved, is the only means of saving up to five hundred amphibian species. Amongst political, financial and practical hurdles, the most fundamental problem for these programmes is lack of knowledge about how to maintain species successfully in captivity. Captive populations have failed to survive or reproduce and, furthermore, captive husbandry may produce animals unsuitable for reintroduction through intra or inter-generational changes. These problems entirely undermine initiatives and if ex situ programs are to succeed, evidence based captive husbandry is needed to support captive breeding programs. In this thesis, I quantify our ignorance of amphibian requirements in captivity. Furthermore, I present investigations into fundamental areas ofamphibian husbandry, about which we currently know very little. I investigate the relationship between amphibians and Ultraviolet B (UVB) radiation and examine the relationship between UVB provision and calcium provision and evaluate routes of dietary calcium supplementation. I also present data on the effects of enrichment and rearing environment on the growth, fitness, behaviour and dermal bacterial communities of captive amphibians. These results, from a range of areas of amphibian husbandry, together demonstrate the power of the captive environment to influence the phenotype and therefore the fitness of amphibians, even within single generations. Additionally, I provide some of the first data addressing key areas of amphibian husbandry that until now have been led mostly or entirely by anecdote and hearsay.
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Variação genética entre e dentro de populações de dipteryx alata vog. para caracteres morformétricos de plântulas, frutos e sementes / Genetic variation between population and inside of dipteryx alata vog. for character morformétricos seedlings, fruit and seedsLuz, Kelly Cristina da [UNESP] 02 September 2016 (has links)
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Previous issue date: 2016-09-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dipteryx alata é considerada uma espécie endêmica do Cerrado brasileiro. Atualmente a espécie necessita de atenção pelo aumento da fragmentação da área de ocorrência. Destaca-se por apresentar madeira resistente e pela a alta produção de frutos. O objetivo do estudo foi estimar os parâmetros genéticos a partir dos caracteres morfométricos dos frutos, sementes e plântulas, de modo a fornecer informações da variabilidade genética existente dentro e entre as procedências da espécie para futuros programas de melhoramento genético e para a conservação. Os frutos foram coletados em três populações naturais, Campo Grande - MS, Ituiutaba - MG e Paulo de Faria – SP, em outubro de 2014. As mudas foram preparadas no viveiro da Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). Para as análises morfométricas dos frutos e sementes, foram mensurados a largura (mm), espessura (mm), comprimento (mm) e massa (g). Nas plântulas foram avaliadas a altura total (cm) e o diâmetro do coleto (mm). Foi utilizado o delineamento blocos completos (DBC) com uma planta por parcela. Observou-se diferenças significativas entre procedências e progênies para os caracteres dos frutos, sementes e plântulas, indicando a presença de variação genética. Os resultados da herdabilidade média, coeficiente de variação individual e acurácia, indicaram que para os frutos, sementes e plântulas há presença de variabilidade genética. Na análise em conjunto das plântulas pode-se verificar que houve diferenças significativas para o efeito de procedência e não significativa para o efeito de progênie. Resultados indicam que esses materiais podem ser utilizados para a conservação genética da espécie e para o melhoramento genético. / Dipteryx alata is considered endemic species of the Brazilian Cerrado. Currently the species needs attention by the increased fragmentation of the occurrence area. It stands out for presenting resistant wood and the high production of fruits. The aim of the study was to estimate genetic parameters from the morphometric fruits, seeds and seedlings, to provide information of genetic variability within and between species provenances for future breeding programs and conservation. The fruits were collected in three natural populations, as Campo Grande - MS, Ituiutaba - MG and Paulo de Faria - SP, in October 2014. The seedlings were prepared in the nursery Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). For morphometric analysis of fruits and seeds were measured (mm) thickness (mm) Length (mm) Mass (g). In the seedlings were evaluated the total height (cm) Stem diameter (mm). We used the design complete block design (RBD) with one plant per plot. There were statistically significant differences among provenances and progenies for the characters of fruits, seeds and seedlings, indicating the presence of genetic variation. The results of the average heritability coefficient of individual variation and accuracy, indicated that for the fruits, seeds and seedlings there is presence of genetic variability. In the analysis of all the seedlings can be seen that there were significant differences in the effect of origin and not significant for the effect of progeny. Results indicate that these materials may be used for genetic conservation of species and genetic improvement.
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Variação genética entre e dentro de populações de dipteryx alata vog. para caracteres morformétricos de plântulas, frutos e sementes /Luz, Kelly Cristina da January 2016 (has links)
Orientador: Miguel Luiz Menezes Freitas / Resumo: Dipteryx alata is considered endemic species of the Brazilian Cerrado. Currently the species needs attention by the increased fragmentation of the occurrence area. It stands out for presenting resistant wood and the high production of fruits. The aim of the study was to estimate genetic parameters from the morphometric fruits, seeds and seedlings, to provide information of genetic variability within and between species provenances for future breeding programs and conservation. The fruits were collected in three natural populations, as Campo Grande - MS, Ituiutaba - MG and Paulo de Faria - SP, in October 2014. The seedlings were prepared in the nursery Fazenda de Ensino, Pesquisa e Extensão (FEPE/UNESP). For morphometric analysis of fruits and seeds were measured (mm) thickness (mm) Length (mm) Mass (g). In the seedlings were evaluated the total height (cm) Stem diameter (mm). We used the design complete block design (RBD) with one plant per plot. There were statistically significant differences among provenances and progenies for the characters of fruits, seeds and seedlings, indicating the presence of genetic variation. The results of the average heritability coefficient of individual variation and accuracy, indicated that for the fruits, seeds and seedlings there is presence of genetic variability. In the analysis of all the seedlings can be seen that there were significant differences in the effect of origin and not significant for the effect of progeny. Results indicate t... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
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Vnímání krásy savců v ZOO Praha: vliv věku a vzdělání respondentů / Perception of beauty of mammals in Prague ZOO: Influence of respondents' age and educationPoláková, Petra January 2016 (has links)
1 Abstract Every year, the number of species considered as endangered increases, especially due to human activities. Nowadays, captive breeding in zoological gardens becomes an option for their survival in refugees. Zoological gardens function as so-called "Noah's Ark", which has the potential to shelter a large amount of individuals from many species. In the future, this opportunity may give us a chance to reintroduce a species that disappeared in the nature. There are many factors influencing which species will be selected to be kept in zoos, e.g., the IUCN status, taxonomical uniqueness, availability, etc., but it was found that especially the size of the animal and the human aesthetic preferences affect the selection. However, every group of animals is evaluated independently in the terms of beauty, and thus, it is necessary to detect these rules and then to apply them to conservation projects. This thesis examines the factors that influence human aesthetic preferences to mammals, both in terms of the characteristics of animals (their colour and morphology), and in terms of human factors (gender, age, education, residence). It was found that especially the pattern, saturation and overall lightness of the animal affect the evaluation of beauty in mammals. On the other hand, dark colours are evaluated...
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Pathologic Findings and Skin Microbiome Structure of Juvenile Eastern Hellbenders (Cryptobranchus alleganiensis alleganiensis) Under Human Care During a High Mortality EventAplasca, Andrea January 2021 (has links)
No description available.
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Population growth and genetic diversity dynamics of modeled conservation methodologies for threatened plant speciesKashimshetty, Yamini 13 September 2016 (has links)
No description available.
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Effects of the captive environment and enrichment on the daily activity of European Bison (<em>Bison bonasus</em>)Godoy, Erika January 2009 (has links)
<p>When breeding wild species in captivity, the animals may gradually become more adapted to captivity and therefore less suited for reintroduction which is the ultimate goal for some species. This study measured the activity budget of European bison (<em>Bison bonasus</em>) in six enclosures in Sweden with the aim to find out how the characteristics of the enclosures – with and without pasture - influenced the activity budget. The results show that there were significant differences in the activity budget, i.e. the activity was higher in the enclosures with pasture than in enclosures with barren ground. However, since barren enclosures were smaller than naturalistic, it was not possible to exclude the effect of size. Judged from observations of bison in the wild, there seems to be a direct correlation between food availability and ranging, indicating that enclosure characteristics affect activity more than size. The bison foraged differently in the two enclosure categories, but the total amount of time spent on feeding did not differ. A feeding enrichment experiment showed to have more positive effects in the barren enclosures than in the naturalistic ones, as the amount of time of inactivity decreased in the former. Since the genetic characteristics of all Swedish bison are very similar, the differences between the two enclosure groups indicate that the animals still have the ability to respond appropriately to improved environmental quality. Hence the next step in the assessment of the suitability of these bison for release would be to study them during an acclimatisation program.</p>
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Effects of the captive environment and enrichment on the daily activity of European Bison (Bison bonasus)Godoy, Erika January 2009 (has links)
When breeding wild species in captivity, the animals may gradually become more adapted to captivity and therefore less suited for reintroduction which is the ultimate goal for some species. This study measured the activity budget of European bison (Bison bonasus) in six enclosures in Sweden with the aim to find out how the characteristics of the enclosures – with and without pasture - influenced the activity budget. The results show that there were significant differences in the activity budget, i.e. the activity was higher in the enclosures with pasture than in enclosures with barren ground. However, since barren enclosures were smaller than naturalistic, it was not possible to exclude the effect of size. Judged from observations of bison in the wild, there seems to be a direct correlation between food availability and ranging, indicating that enclosure characteristics affect activity more than size. The bison foraged differently in the two enclosure categories, but the total amount of time spent on feeding did not differ. A feeding enrichment experiment showed to have more positive effects in the barren enclosures than in the naturalistic ones, as the amount of time of inactivity decreased in the former. Since the genetic characteristics of all Swedish bison are very similar, the differences between the two enclosure groups indicate that the animals still have the ability to respond appropriately to improved environmental quality. Hence the next step in the assessment of the suitability of these bison for release would be to study them during an acclimatisation program.
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Fragmentos florestais e testes de progênies : opções para a coleta de sementes em espécies arbóreas nativas do Cerrado no Bolsão Sul-Mato-Grossense /Cambuim, José. January 2017 (has links)
Orientador: Mario Luiz Teixeira de Moraes / Abstract: The forest fragment and progeny tests, with the function of assisting conservation, rehabilitation of ecological processes and promoting biodiversity conservation, play an important role in the restoration of degraded areas and reduce the negative effects of the destruction of natural environments. This work aimed to know the population structure, spatial distribution and effective size of native tree species present in a cerrado forest fragment, besides estimating the genetic variability in a test of mixed progenies of Myracrodruon urundeuva; Terminalia argentea and Astronium fraxinifolium; from silvicultural characters in Selvíria - MS, with a view to transforming them into an area to subsidize seed collection. In the forest fragment were measured and identified 1187 individuals with DBH ≥ 10 cm, which make up the arboreal forest canopy. In an area of 0,89 ha were sampled, belonging to 60 species distributed in 31 families, with emphasis on the Fabaceae family with 11 species. The Shannon-Weaver index showed a H '= 2,98 nats ind-1, which can be considered as a mean diversity. The species with the highest Import Value Index (IVI) were Copaifera landesdorffii, Diptychandra aurantiaca, Parapiptadenia rigida, Qualea grandiflora, Qualea parviflora, Vochysia tucanorum, Tapirira guianensis, Astronium fraxinifolium, Xylopia aromatica, and Mabea fistulifera. Thus, among the species found with the highest IVI can be classified as potential for the lease of matrix trees to subsidize t... (Complete abstract click electronic access below) / Resumo: O fragmento florestal e os testes de progênies, com a função de auxiliar a conservação, reabilitação dos processos ecológicos e promover a conservação da biodiversidade, tem um papel importante nos processos de restauração de áreas degradadas e diminuir os efeitos negativos da destruição dos ambientes naturais. Este trabalho objetivou conhecer a estrutura populacional, distribuição espacial e tamanho efetivo de espécies arbóreas nativas presente em um fragmento florestal de cerrado, além de estimar a variabilidade genética num teste de progênies misto de Myracrodruon urundeuva; Terminalia argentea e Astronium fraxinifolium; a partir dos carácteres silviculturais em Selvíria – MS, com vistas de transformá-las em área para subsidiar coleta de sementes. No fragmento florestal foram mensurados e identificados 1187 indivíduos com DAP ≥ 10 cm, que compõem o dossel arbóreo da floresta. Em uma área de 0,89 ha foram amostrados, pertencentes a 60 espécies distribuídas em 31 famílias, com destaque para a família Fabaceae com 11 espécies. O índice de ShannonWeaver apresentou um H’ = 2,98 nats ind-1 , o que pode ser considerado como uma diversidade média. As espécies de maior Índice de Valor de Importância (IVI) foram Copaifera landesdorffii, Diptychandra aurantiaca, Parapiptadenia rigida, Qualea grandiflora, Qualea parviflora, Vochysia tucanorum, Tapirira guianensis, Astronium fraxinifolium, Xylopia aromatica, e Mabea fistulifera. Assim, dentre as espécies encontradas com o maior IVI pod... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
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