Tesi: "Reptiles Development"

1

Nash, Darryn James. "An assessment of mitigation translocations for reptiles at development sites". Thesis, University of Kent, 2017. https://kar.kent.ac.uk/65820/.

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Abstract (sommario):

All native reptile species are protected against harm through their inclusion on UK legislation. With the exception of two species, this protection does not extend to reptile habitat. As a result, reptiles are frequently subject to mitigation translocations to facilitate the development of land. However, there are few published studies of the effects of mitigation translocation on reptile populations and whether such translocations are effective conservation interventions. The effectiveness of translocation was tested through a combination of: 1) field surveys of sites subject to mitigation across England and Wales; 2) the radio tracking of translocated adders; 3) the monitoring of a population of slow-worms at site where they were released 20 years ago; and 4) a penning experiment to test whether viviparous lizards attempt to disperse from the release site. Very few translocated reptiles were encountered during the monitoring of release sites. This paucity of recaptures is either due to post-release mortality, imperfect detection or dispersal. Translocated male adders dispersed farther and had larger home range sizes than resident conspecifics. Some male adders undertook large unidirectional migrations back to the donor site crossing areas of unsuitable habitat as they did so. A population of slow-worms persisted at an isolated site two decades after translocation, albeit in relatively small numbers. Body condition improved over 20 years and the population resumed breeding and recruitment. The temporary penning of viviparous lizards was effective in preventing post-release dispersal and resulted in an increase in recapture rates of greater than 16 times when compared to unpenned viviparous lizard populations. The fact that no lizards were recaptured in the unpenned areas provides strong evidence for the effect of post-release dispersal. Although, mitigation translocations may prevent the immediate death of animals that would otherwise be destroyed with their habitat, there is little evidence that they are compensating for the loss of populations on a broad scale.

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2

Northrop, Robert John. "Development and assessment of a wildlife habitat relationship model for terrestrial vertebrates in the state of Maryland". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 152 p, 2009. http://proquest.umi.com/pqdweb?did=1885544331&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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3

Johnston, Sonya D. "Development of the pulmonary surfactant system in non-mammalian amniotes /". Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phj737.pdf.

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4

Sartori, Marina Rincon. "Excreção de nitrogênio em embriões de iguana Iguana iguana (Reptilia; Squamata)". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-24082012-113604/.

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Tabelas de estágio embrionário podem ser utilizadas para detectar semelhanças e diferenças de caracteres entre grupos e como ferramenta para estudos baseados na fase embrionária. Neste estudo, ovos do lagarto Iguana iguana foram utilizados para a elaboração de uma tabela de estágios e para determinar o padrão de excreção durante o desenvolvimento. Iguana é um modelo conveniente por produzir numerosas desovas de ovos de tamanho grandes, propiciando um fácil manuseio e um bom número de réplicas. Após a oviposição, 18 estágios embrionários foram determinados durante os quais uréia foi o resíduo nitrogenado principal. Apesar do iguana ser o primeiro lagarto estudado, o padrão ureotélico é comum entre a maioria das espécies reptilianas estudadas até o momento. A casca pergaminácea permite que os ovos dobrem em massa devido à absorção de água, e o mecanismo pelo qual os embriões lidam com a diluição e osmolaridade resultante é um tema interessante para futuros trabalhos e comparações com espécies de cascas rígidas. Há evidência de desenvolvimento heterocrônico dos membros e o desenvolvimento de iguana é similar ao do lagarto Anolis sagrei, também do clado Iguania. Mais estudos de desenvolvimento de lagartos são necessários e a utilização de critérios morfológicos similares para facilitar a comparação de eventos embrionários.
A Table of embryonic stages can be used to detect similarities and differences in developmental features between groups and as a tool for studies based on embryonic phase. In this study, eggs of the lizard Iguana iguana were used to elaborate a staging table and to determine the nitrogen excretion pattern during the development. Iguana is a convenient model for having a large clutch of large eggs, allowing an easy handling and a good number of replicates. After oviposition embryonic stages were determined during which urea was the main nitrogen waste. Although iguana is the first lizard studied, the ureotelic pattern is common among the majority of reptilian species so far studied The pergaminaceous shell allows that the eggs double in mass due to water absorption, and the mechanism and how the egg deals with dilution and resultant osmolarity is an interesting issue for future works and comparisons with species of rigid eggshells. There is evidence of heterocronic development of the limbs and the development of iguana is similar to the lizard Anolis sagrei, also from the clade Iguania. Further studies on lizard evelopment are required and the use of similar morphological approach to facilitate comparisons of embryonic events

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5

Godinez, Ricardo. "Comparative Genomics of the Major Histocompatibility Complex in Amniotes". Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10685.

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The major histocompatibility complex region (MHC) is a multi gene family present in all jawed vertebrates, with a fundamental role in vertebrate immunity. More than two decades of studies have resulted in the characterization of over a dozen MHC regions, and models of evolution explaining that the MHC has gradually increased in size and gene content since its origins without addressing their genomic context or the environmental selective forces. Furthermore, a compelling reconstruction of the evolutionary history of the MHC has been hampered due to phylogenetic gaps and the absence of comparative phylogenetic methods applied to comparative genomics. Here I reconstruct 320 MY of MHC evolution using 42 amniote genomes using improved gene annotations, genomic alignments and phylogenetic algorithms to reconstruct the evolution of the MHC at three levels of phylogenetic resolution. The first one describes 25 MY of evolution of the primate MHC using eight Human and four non-Human primate MHC haplotypes. Results suggests that highly dense gene segments have a strikingly conserved gene organization, and six conserved and highly rearranging segments overlap genes that are most commonly associated to disease. Phylogenomic analysis implies that the MHC has remained stable in gene content and size, with significantly increased duplication rates in the primate ancestors. The second one describes 280 MY of MHC evolution through the first characterization of reptilian MHC region, which combines mammalian, reptilian, Bird and amphibian characteristics, which favors the hypothesis of the existence of a primordial MHC in which natural killer receptors, CD1 and lectin genes co-exist. The Anolis MHC expands our understanding of the origins of the exceptionally small Bird MHC regions and provides further information about the organization and size of the ancestral amniote MHC. The third one compares 42 amniote MHC regions and map gene duplications and losses to further evaluate the mode and tempo of the evolution of the region. Comparative phylogenetic methods imply that the genomic and environmental factors affect the diversification of MHC during 320 My of evolution.

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6

Fuentes, Ricardo Arturo Guerra. "\"O desenvolvimento embriológico do crânio no clado Iguania e sua contribuição para a filogenia do grupo (Reptilia, Squamata)\"". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-26042007-153347/.

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Este estudo compreende a descrição do desenvolvimento do crânio cartilaginoso e dérmico das seguintes espécies de lagatos iguanídeos: Anisolepis grilli (Leiosauridae), Hoplocercus spinosus (Hoplocercidae), Iguana iguana e Tropidurus sp. (Tropiduridae) e Tupinambis merianae (Teiidae), um representatnte de Scleroglossa. A descrição do desenvolvimento do crânio destes taxons é inédita. O objetivo deste trabalho é descrever e comparar os padrões de desenvolvimento dos lagartos que compõe o clado Iguania com os padrões já descritos para outros grupos de Squamata. Através do processo de diafanização foram estudadas séries embriológicas das espécies supracitadas. As descrições foram complementadas com a descrição do desenvolvimento craniano de Polychrus acutirostris (Polychrotidae) (Guerra-Fuentes, 2002). O padrão de desenvolvimento dos Iguania é muito similar com o descrito para outros grupos de lagartos. Foram encontradas algumas particularidades no desenvolvimento dos elementos dos arcos viscerais e da cápsula nasal dos táxons analisados. Algumas estruturas catilaginosas sugerem relações de parentesco entre grupos de Iguania.
This study comprises the description of the development of the cartilaginous and dermic skull of the following iguanid lizards: Anisolepis grilli (Leiosauridae), Hoplocercus spinosus (Hoplocercidae), Iguana iguana and of the Scleroglossa specie Tupinambis merianae (Teiidae). The description of the skull development of these taxons is unprecedented. The aim of this study is to describe and compare the development patterns of the lizards which make up the Iguania clade to the previously described patterns for other Squamata groups. The embryonic series of the above mentioned species were studied after clearing and staining. The descriptions were complemented by the description of the development of the cranium of Polychrus acutirostris (Polychrotidae) (Guerra-Fuentes, 2002). The development pattern of Iguania is very similar to previously described patterns for other lizard groups. A number of particular traits were found in the development of the elements of the visceral arches and of the nasal capsule of the studied taxons. Some cartilaginous structures suggest a close relation amongst groups of Iguania.

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7

Yvorra, Alain. "Croissance folliculaire et developpement du corps jaune chez le lezard vivipare, lacerta vivipara jacquin : evolution au cours du cycle sexuel et analyse des mecanismes de regulation". Paris 6, 1986. http://www.theses.fr/1986PA066270.

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8

Johnston, Sonya D. (Sonya Denise). "Development of the pulmonary surfactant system in non-mammalian amniotes". 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phj737.pdf.

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"March 2001". Bibliography: leaves 193-238. Relates changes in the development of the pulmonary surfactant system in response to birth strategy, lung morphology and phylogeny in order to determine the extent of conservation in this process, by quantifying the total of phsospholipid, disaturated phospholipid and cholesterol in the lung washings of embryonic and hatchling chickens, oviparous bearded dragons and viviparous sleepy lizards, snapping turtles and green sea turtles throughout the final stages of incubation and gestation. Finds that the pattern of development of pulmonary surfactant lipids is consistent with that of mammals.

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9

Johnston, Sonya D. (Sonya Denise). "Development of the pulmonary surfactant system in non-mammalian amniotes / Sonya D. Johnston". Thesis, 2001. http://hdl.handle.net/2440/19859.

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"March 2001".
Bibliography: leaves 193-238.
vii, 238 leaves : ill. (some col.) ; 30 cm.
Relates changes in the development of the pulmonary surfactant system in response to birth strategy, lung morphology and phylogeny in order to determine the extent of conservation in this process, by quantifying the total of phsospholipid, disaturated phospholipid and cholesterol in the lung washings of embryonic and hatchling chickens, oviparous bearded dragons and viviparous sleepy lizards, snapping turtles and green sea turtles throughout the final stages of incubation and gestation. Finds that the pattern of development of pulmonary surfactant lipids is consistent with that of mammals.
Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 2001

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10

Theis, Susanne [Verfasser]. "Origin and development of cucullaris-, trapezius-sternocleoidomastoid muscles in birds, mammals and reptiles / vorgelegt von Susanne Theis". 2010. http://d-nb.info/1001529545/34.

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11

Whitehead, Peter John. "Respiration and energy utilisation in the eggs of the Australian freshwater crocodile, `Crocodylus johnstoni` Krefft, 1873". Thesis, 1987. http://hdl.handle.net/2440/113403.

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12

Attard, Lydia. "The Development and Evaluation of a Gut-loading Diet for Feeder Crickets Formulated to Provide a Balanced Nutrient Source for Insectivorous Amphibians and Reptiles". Thesis, 2013. http://hdl.handle.net/10214/6653.

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Abstract (sommario):

In captivity the diversity of prey items for obligate insectivores is limited and nutritionally inadequate, leading to nutrient deficiencies. Zoological institutions utilize gut-loading, an insect supplementation technique, to compensate for these nutrient shortcomings. This study developed a gut-loading diet (GLD) to enhance the nutritive quality of the domestic house cricket (Acheta domestica) for insectivorous amphibians and reptiles, with the requisite that it also met cricket foraging and palatability needs. Gut-loaded cricket analysis established its effectiveness such that the targeted level of most nutrients required by the end consumers were met after consuming the diet for 24 hrs (Ca:P of 1.127; vitamin A (retinyl acetate) level of 12,607 IU/kg; vitamin E level of 342 IU/kg and a linoleic fatty acid level of 4.62%), peaking at 2 days for some and remained above targeted amounts for at least 4 days. A list of cricket gut-loading optimization husbandry procedures has also been recommended.

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13

"Transcriptomic and Cellular Studies of Tail Regeneration in Saurian Reptiles". Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.57085.

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abstract: Traumatic injury to the central nervous or musculoskeletal system in traditional amniote models, such as mouse and chicken, is permanent with long-term physiological and functional effects. However, among amniotes, the ability to regrow complex, multi-tissue structures is unique to non-avian reptiles. Structural regeneration is extensively studied in lizards, with most species able to regrow a functional tail. The lizard regenerated tail includes the spinal cord, cartilage, de novo muscle, vasculature, and skin, and unlike mammals, these tissues can be replaced in lizards as adults. These studies focus on the events that occur before and after the tail regrowth phase, identifying conserved mechanisms that enable functional tail regeneration in the green anole lizard, Anolis carolinensis. An examination of coordinated interactions between peripheral nerves, Schwann cells, and skeletal muscle reveal that reformation of the lizard neuromuscular system is dependent upon developmental programs as well as those unique to the adult during late stages of regeneration. On the other hand, transcriptomic analysis of the early injury response identified many immunoregulatory genes that may be essential for inhibiting fibrosis and initiating regenerative programs. Lastly, an anatomical and histological study of regrown alligator tails reveal that regenerative capacity varies between different reptile groups, providing comparative opportunities within amniotes and across vertebrates. In order to identify mechanisms that limit regeneration, these cross-species analyses will be critical. Taken together, these studies serve as a foundation for future experimental work that will reveal the interplay between reparative and regenerative mechanisms in adult amniotes with translational implications for medical therapies.
Dissertation/Thesis
Differentially Expressed Genes in the Early Regenerating Lizard Tail
Gene Ontology of Differentially Expressed Genes in the Early Regenerating Lizard Tail
KEGG and Reactome Pathway Analysis of Differentially Expressed Genes in the Early Regenerating Lizard Tail
3D Reconstruction of an Alligator Regenerated Endoskeleton
Lateral 2D Serial Sections of a Regenerated Alligator Tail
Doctoral Dissertation Biology 2020

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14

Crawford, Nicholas Geoffrey. "Genomic analysis of macro- and micro-evolution in the reptilia". Thesis, 2013. https://hdl.handle.net/2144/15658.

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Recent advances in high-throughput, genomic sequencing allow unprecedented insight into the evolution of biodiversity. Chapter 1 of this thesis is a phylogenetic study of 1,145 sequenced loci, isolated using a novel high-throughput sequence capture methodology to address the phylogenetic position of turtles within tetrapods. The results reported here unambiguously place turtles as sister to archosaurs and resolve this long-standing question. Chapter 2 investigates the genetic basis of colorful pigmentation in the Green anole (Anolis carolinensis) by sequencing complete transcriptomes from the green dorsal, white ventral and pink dewlap skin. Anoles comprise an adaptive radiation of more than 400 species and color plays a central role in their ecology and evolution, but little is known about the genetic basis of colorful pigmentation in any vertebrate. This study identified 1,719 differentially expressed genes among the three differently colored tissues. Twenty-three of these genes are involved in melanin, pteridine, and carotenoid pigmentation pathways that contribute to the coloration of anole skin. Identifying candidate genes for colorful pigmentation is a significant advance that opens the field for comparative analysis in other taxa. To determine if the genes identified in Chapter 2 are involved in population divergence and speciation, Chapter 3 investigates the complete genomes of twenty individuals from two closely related subspecies of Anolis marmoratus. While the two subspecies differ markedly in pigmentation, this study found few genetic differences between populations except in five regions of the genome, which together contained 447 genes. Of these genes, only two, melanophilin (mlph) and 'cluster of differentiation 36' (cd36), are associated with pigmentation. The intersection of the genes identified in Chapter 2 and Chapter 3 includes both cd36 and mlph, suggesting that both are involved in divergence of coloration. Cd36 is of particular interest because it regulates the uptake of carotenoid pigments and is an important candidate gene contributing to carotenoid pigmentation. Together, this research demonstrates the power of genomic approaches to address fundamental questions in systematics, micro-evolution, and speciation. The findings bolster the emerging field of phylogenomics and broadly impact future research into the genetic basis of coloration in vertebrates.

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15

"Forces driving thermogenesis and parental care in pythons". Doctoral diss., 2012. http://hdl.handle.net/2286/R.I.15146.

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abstract: Parental care provides many benefits to offspring. One widely realized benefit is enhanced regulation of offspring's thermal environment. The developmental thermal environment during development can be optimized behaviorally through nest site selection and brooding, and it can be further enhanced by physiological heat production. In fact, enhancement of the developmental thermal environment has been proposed as the initial driving force for the evolution of endothermy in bird and mammals. I used pythons (Squamata: Pythonidae) to expand existing knowledge of behavioral and physiological parental tactics used to regulate offspring thermal environment. I first demonstrated that brooding behavior in the Children's python (Antaresia childreni) is largely driven by internal mechanisms, similar to solitary birds, suggesting that the early evolution of the parent-offspring association was probably hormonally driven. Two species of python are known to be facultatively thermogenic (i.e., are endothermic during reproduction). I expand current knowledge of thermogenesis in Burmese pythons (Python molurus) by demonstrating that females use their own body temperature to modulate thermogenesis. Although pythons are commonly cited as thermogenic, the actual extent of thermogenesis within the family Pythonidae is unknown. Thus, I assessed the thermogenic capability of five previously unstudied species of python to aid in understanding phylogenetic, morphological, and distributional influences on thermogenesis in pythons. Results suggest that facultative thermogenesis is likely rare among pythons. To understand why it is rare, I used an artificial model to demonstrate that energetic costs to the female likely outweigh thermal benefits to the clutch in species that do not inhabit cooler latitudes or lack large energy reserves. In combination with other studies, these results show that facultative thermogenesis during brooding in pythons likely requires particular ecological and physiological factors for its evolution.
Dissertation/Thesis
Ph.D. Biology 2012

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Tesi sul tema "Reptiles Development"

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