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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Identifying the Use of Turtles and Tortoises at the Prehistoric Penny Site at Cape Canaveral

Griffin, Alexandria 01 January 2024 (has links) (PDF)
As people live in an area, they leave behind an assortment of cultural items they once utilized. Some of these items may include pottery or bones from animals they used as food. Analysis of these bones can give a glimpse into how they managed their resources in the environment around them, including which ecosystems they chose to exploit, and which taxa they prioritized for consumption or cultural purposes. The Indian River Lagoon in Florida is a diverse costal lagoon with many various overlapping ecosystems and ecotones available for prehistoric peoples to utilize. Comparing the frequency of taxa representing different local environments such as the marine, terrestrial, and estuary environments will help us to understand how the people who lived at the Penny site prioritized these many resources. This study intends to analyze turtle remains specifically because different species are present in all three environments. Amongst the four analyzed test units at the Penny site, 1,417 turtle elements were identified. Overall, turtle shell (carapace or plastron) was the most identified element across each analyzed test unit. Results demonstrate that turtles were not only consumed, but their shell was used for cultural purposes as well.
32

Development of Cardiovascular Regulation in Embryos of the Domestic Fowl (Gallus Gallus), with a Partial Comparison to Embryos of the Desert Tortoise (Gopherus Agassizii)

Crossley, Dane Alan 08 1900 (has links)
In adult vertebrates, cardiovascular regulation is accomplished by numerous systems with neural, hormonal and local components responsible for the majority of regulation. These regulatory components work in concert to maintain the essential function of blood perfusion to adult tissues. Given the essential nature of this function it is therefore surprising that the development of cardiovascular regulation during gestation is poorly understood. The majority of what is known is based on a single vertebrate model, the fetal lamb. The fetal lamb has been used in multiple studies due to the clear clinical applications and has been pivotal in understanding the onset of regulation in developing vertebrates. However, study on the fetal lamb is limited to the latter 40% of gestation and has the added complication of an in-utero developmental strategy. Therefore the primary focus of this dissertation was to characterize basic cardiovascular regulation in the chicken embryo to provided the needed information for it's use an alternative to the fetal lamb. Developing chicken embryos rely on both alpha and beta adrenergic tones to maintain normal heart rate and arterial blood pressure during incubation. However, on day 21, just prior to hatch, these animals lose both tones on arterial pressure suggesting the onset of adult regulation. Cholinergic tone, however, was absent throughout chicken development indicating that it must mature during the neonatal life. Adult cardiovascular reflexes become apparent late in chicken development with a clear baroreflex specifically operating initially on day. However, an adult response to changes in ambient gas tension was absent during incubation suggesting embryos possess unique regulatory systems that are absent in adult chickens. This mechanism is comprised entirely of adrenergic systems with no cholinergic action during change in ambient gas tension. Similar developmental patterns were determined in embryos of the desert tortoise suggesting fundamental differences between in-utero and ex-utero developing vertebrates.
33

Temperature-Dependent Sex Determination in Manouria Emys Emys, The Asian Forest Tortoise

Emer, Sherri Ann 04 May 2007 (has links)
Captive husbandry programs in zoos have documented nesting behavior and have successfully hatched Manouria emys emys, but data on sex determining mechanisms and sex ratios are absent. A total of 30 M. e. emys eggs were artificially incubated at five different temperatures in constant humidity. Mean incubator temperatures were 24.99°C, 25.06°C, 27.18°C, 28.00°C, and 30.79°C. Incubation duration ranged from 60 days to 92 days, and hatching success was 50%. Sex determined by histology and laparoscopy resulted in male differentiation at low temperatures (24.99°C, 27.18°C) and female differentiation at high temperatures (30.79°C). Pivotal temperature was estimated to be 29.29°C. The following investigation into temperature-dependent sex determination (TSD), including its presence or absence, pattern, and pivotal temperature, has implications for studies of adaptive significance of reproductive behaviors and of chelonian phylogenetic history. Additionally, the proposed study can provide foundations for conservation management decisions, and for captive breeding programs.
34

Biodiversity and systematics of apicomplexan parasites infecting South African leopard and hinged tortoises

15 March 2010 (has links)
M.Sc. / Research into blood protozoans (haematozoans) infecting African tortoises is scanty with only a few records published, many during the early part of the last century. Little research had been done on the blood parasites of tortoises examined in this study namely, Kinixys lobatsiana, K. belliana belliana, K. natalensis, Geochelone pardalis pardalis, G. pardalis babcocki and Chersina angulata. The study therefore aimed to: 1) examine apicomplexan haematozoan parasites infecting several of South Africa’s indigenous tortoises and compare them with published species descriptions, especially from neighbouring Mozambique; 2) provide host details (identity, ectoparasites, host weight and gender, effects of blood parasites on host cells) and locality records in different seasons for described and new apicomplexan species; 3) describe new and recorded parasites using morphometrics and, if possible, ultrastructural characteristics 4) attempt apicomplexan DNA extraction, amplification and, if feasible, purification; and 5) establish a basis for future research as a result of the acquired knowledge. During the current study, 154 tortoises of six species in three genera, both captive and wild, and from four South African provinces (Gauteng, North West, Kwazulu-Natal and Western Cape) were sampled. Giemsa stained blood smears and use of image analysis enabled morphometric analysis of the apicomplexans and their effects on host cells, while some blood preserved in Karnovsky’s and Todd’s fixatives received detailed examination by transmission electron microscopy. Lastly, blood preserved in lysis buffer during collection, and with the highest parasitaemias, was subjected to parasite DNA extraction and amplification. Comparisons between a published account of apicomplexans recorded from K. b. belliana in Mozambique, and those found in the current study, identified two haemogregarine species. In the present research, Haemogregarina fitzsimonsi Dias, 1953 infected 2/27 (7%) wild North West K. lobatsiana, 2/3 (66%) captive Kwazulu-Natal K. natalensis, 7/14 (50%) captive Kwazulu- Natal K. b. belliana, 3/6 (50%) captive Kwazulu-Natal G. p. pardalis, 2/41 (5%) wild G. p. babcocki and 13/37 (35%) captive Gauteng G. pardalis. In addition, Haemogregarina parvula Dias, 1953, infected 2/14 (14%) captive K. b. belliana and 1/10 (10%) captive G. p. pardalis. An unknown species of haemogregarine, possibly also H. fitzsimonsi occurred in 6/16 (38%) Chersina angulata from the Western Cape. As well as haemogregarines, two haemoproteids were identified: Haemoproteus balazuci Dias, 1953 infected 2/27 (7%) wild North West K. lobatsiana, 2/2 (100%) captive Gauteng K. lobatsiana and 1/41 (2%) wild North West G. p. babcocki; Haemoproteus sp., a likely new species, was found in 1/3 (33%) captive K. natalensis. Infections with Haemogregarina and Haemoproteus were not concurrent in this study, but were found to occur concurrently in Dias (1953) findings, and only the two Haemogregarina spp. occurred together in captive Kwazulu-Natal G. p. pardalis tortoises, which do not occur naturally in the region. Haemogregarina fitzsimonsi did not appear region or host specific, since it infected 5/6 species of tortoises from all provinces sampled. Haemogregarina parvula apparently existed only in tortoises from Kwazulu-Natal. Furthermore, captive Gauteng female tortoises were found to have a higher rate of infection than males and heavier tortoises showed a lower intensity infection than lighter and younger tortoises. On average season appeared to have a slight affect on parasite prevalence, with a higher prevalence during the summer rather than the winter, possibly a result of the activity of the assumed vector, which may be the tick species Amblyomma marmoreum (found on G. pardalis) and/or Amblyomma hebraeum (found on C. angulata). For the new Haemoproteus sp., the small sample size meant that meaningful data on host-specificity and range was not gathered, but Hp. balazuci occurred in K. lobatsiana in the drier regions of the North West and Gauteng. Although DNA extraction was possible for H. fitzsimonsi, the technique requires further refinement and samples with greater parasitemias before it can be used with additional material, and sequencing can be attempted. Thus, new localities, hosts, host data and possible vectors (ticks) were recorded for the apicomplexan species identified by Dias (1953) and they were re-described using modern techniques. Also, possibly new Haemogregarina and Haemoproteus spp. were recorded, but their identity requires confirmation by DNA analysis. It is anticipated that these, and future results, will increase the knowledge of the ecology and biodiversity of apicomplexan haematozoans parasitising chelonian hosts in South Africa, with possible application to the conservation of these and other tortoise species around the world.
35

Use of environmental variables to infer gene flow and population structure in the gopher tortoise (Gopherus polyphemus) and predict the seroprevalence of an emerging infectious disease

Clostio, Rachel Wallace 05 August 2010 (has links)
Understanding worldwide declines in reptiles due to factors such as habitat loss and emerging infectious disease has become an increasingly important focus in conservation biology. Here, I use novel approaches from the field of landscape genetics to combine spatial genetic data with landscape data at both regional and local spatial scales to explore natural and anthropogenic landscape features that shape population structure and gene flow in a federally threatened reptile, Gopherus polyphemus. I also utilize approaches from the field of spatial epidemiology to examine the extent to which environmental variables can be used to predict the seroprevalence of an associated pathogen Mycoplasma agassizzi in gopher tortoise populations. Using mitochondrial data, I find evidence of a historical barrier to gene flow that appears to coincide with the Apalachicola River. I also discover low genetic diversity and evidence of population bottlenecks in the western portion of the range. My evaluation at the regional scale shows that dispersal is limited by geographic distance, areas of low elevation and major roads ways. A finescale study reveals no evidence of spatial genetic structure within a 14 x 35 km area. However, soil type is significantly correlated with pairwise genetic distances between individuals, suggesting that this variable influences fine-scale population structure in the gopher tortoise. In addition to soil, high density canopy cover is an important factor impeding gene flow at the local level for females, while land cover type explains some of the genetic variance between males. Finally, temperature and precipitation appear to be important predictors of the seroprevalence of the pathogen Mycoplasma agassizii in gopher tortoises. The probability of an individual testing seropositive for exposure to this disease increased with high temperature and low precipitation values. The methods presented in this dissertation evaluate novel approaches for assessing the influence of environmental variables on population structure, dispersal and disease occurrence and could be applied in future studies of other threatened and endangered taxa.
36

Avaliação ecocardiográfica modo-B, modo-M e Dopplerfluxométrica em Chelonoidis carbonaria (SPIX,1824) / Echocardiographic evaluation B-mode, M-mode and Dopplerfluxometric in Chelonoidis carbonaria (SPIX, 1824)

Bonatelli, Shayra Peruch [UNESP] 16 February 2017 (has links)
Submitted by SHAYRA PERUCH BONATELLI null (shayrabonatelli@gmail.com) on 2017-02-24T23:49:47Z No. of bitstreams: 1 Dissertação Repositório.pdf: 1006643 bytes, checksum: 238b25a3d3559dba4417f37e5c5bda4d (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-03-06T18:04:26Z (GMT) No. of bitstreams: 1 bonatelli_sp_me_bot.pdf: 1006643 bytes, checksum: 238b25a3d3559dba4417f37e5c5bda4d (MD5) / Made available in DSpace on 2017-03-06T18:04:26Z (GMT). No. of bitstreams: 1 bonatelli_sp_me_bot.pdf: 1006643 bytes, checksum: 238b25a3d3559dba4417f37e5c5bda4d (MD5) Previous issue date: 2017-02-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os animais da espécie Chelonoidis carbonaria (Spix,1824) tem grande importância na questão conservacionista e vêm se tornando cada vez mais comuns como animais de estimação. O diagnóstico das diversas doenças em quelônios é um desafio para o clínico, pois a presença de casco e plastrão impede um exame físico detalhado com ausculta e palpação. A ecocardiografia tem se tornado valiosa no diagnóstico de diferentes afecções cardíacas. Este estudo teve como objetivo realizar a avaliação ecodopplercardiográfica em indivíduos Chelonoidis carbonaria (Spix,1824) a fim de estabelecer referências de normalidade que poderão auxiliar futuros diagnósticos de cardiopatias nestes animais. Ao modo-B observou-se um coração composto por três câmaras e duas válvulas atrioventriculares e em todos os animais observou-se fluído pericárdico. A Dopplerfluxometria revelou um padrão de onda de baixo fluxo na via de saída no ventrículo com velocidade média de pico sistólico de 34,10cm/s. O fluxo de preenchimento ventricular se mostrou bifásico, sendo que a razão entre o pico diastólico inicial e final mostrou-se menor que 1, tendo média de 0,66. A fração de encurtamento foi calculada por dois métodos, um atrial e outro ventricular, apresentando médias de 34,47% para o átrio direito, 46,90% para o esquerdo e 29,46% para o ventrículo, mantendo-se próximo à faixa de normalidade da fração de encurtamento ventricular conhecida para cães. Esta técnica ultrassonográfica se mostra de alta eficácia para avaliação cardíaca em animais da espécie Chelonoidis carbonaria, submetidos à anestesia geral. / The animals of the Chelonoidis carbonaria (Spix, 1824) specie have great importance in the conservacionist issue and are becoming increasingly common as pet. Diagnosis of various diseases in chelonian is a challenge for the clinician. The presence of shell and plastron avoid a detailed physical examination with auscultation and palpation. Echocardiography is very useful for diagnosis of different cardiac diseases. This study aimed to perform an echodopplercardiographic evaluation in Chelonoidis carbonaria (Spix, 1824) individuals to establish reference value, providing information for the future diagnosis of heart disease in these animals. At B-mode evaluation, we observed a heart consisted of three cameras and two atrioventricular valves and all the animals presented pericardial fluid. The Doppler ultrasound revealed a low flow wave pattern in the ventricular outflow with mean velocity of systolic peak of 34,10cm/s. The atrioventricular filling flow revealed a biphasic wave pattern, being the ratio between the diastolic and sistolic peak lower than one with mean value of 0,66. Shortening fraction was calculated by two methods, one atrial and another ventricular, with mean value of 34,47% for the right atrium, 46,90% for the left and 29,46% for the ventricle, remaining near the range of the ventricular shortening fraction already known for dogs. This sonographic technique shows high efficiency for the cardiac evaluation in animals of the Chelonoidis carbonaria (Spix, 1824) specie submitted to general anesthesia. / CNPq: 134265/2015-7
37

A Survey of Gopherus polyphemus Intestinal Parasites in South Florida

Unknown Date (has links)
Gopherus polyphemus populations are diminishing throughout their range due to urbanization, fragmentation, and poor management of habitats. Increased population densities, poor habitat quality, and lack of fire may influence disease transmission. Parasite roles within wild tortoise populations are largely unknown, despite evidence these pathogens may pose health risks. This study provides a baseline of gopher tortoise endoparasites across South Florida and reports on how varying environmental and tortoise characteristics may affect endoparasite species prevalence, approximate loads, and overall distributions. Tortoise fecal samples were taken from five differing SF habitats. Seven species of intestinal parasites were discovered from 123 tortoises. Identified parasites include endo-helminths such as cyathostomes, pinworms, ascarids, flukes, and protozoans including Eimeria, Cryptosporidium, and Amoeba species. Significant differences in parasite prevalence and loads were seen between sampling years, seasons, size classes, and sites, however, overall parasite distributions suggest parasitism remains relatively ubiquitous throughout most host and site characteristics. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
38

MYCOPLASMA AGASSIZII IN THE SONORAN POPULATION OF THE DESERT TORTOISE IN ARIZONA

Jones, Cristina Ann January 2008 (has links)
Upper Respiratory Tract Disease (URTD), caused by the pathogens Mycoplasma agassizii and M. testudineum, has been documented in the desert tortoise (Gopherus agassizii). Although URTD was identified as a putative agent that led to federal listing of the Mojave population of the desert tortoise, little is known about this disease in the Sonoran population of the desert tortoise. The purpose of this study was to determine: 1) the prevalence of URTD across an urban gradient in Greater Tucson, Arizona, 2) the relationship between URTD and captive and free-ranging tortoises in Mohave, Maricopa, and Pima counties in Arizona, and 3) the effects of URTD on desert tortoise home range size and winter temperature selection.
39

A LONG-TERM INVESTIGATION OF THE FEDERALLY THREATENED DESERT TORTOISE (<em>GOPHERUS AGASSIZII</em>) AT A WIND ENERGY FACILITY IN SOUTHERN CALIFORNIA

Agha, Mirza Mickey 01 January 2015 (has links)
With the recent increase in utility-scale wind energy development and current climate variation in the desert southwest US, researchers have become increasingly concerned with the reaction of wildlife and critical habitat. Understanding the relationships among monitoring efforts, climate, industrial landscapes and wildlife is critical to effective management. Given the need for information available on how these potential stressors affect terrestrial wildlife, my objective was to determine how climate variation, wind energy facilities (WEF) and monitoring efforts by researchers influence behavior and survivorship in a population of the federally threatened desert tortoise (Gopherus agassizii). Data were collected via surveys, motion-sensor camera trapping and radio-telemetry during the span of two decades at a WEF in California. Using capture-mark-recapture survivorship analysis and generalized linear mixed-effects models, I acquired long-term estimates of survivorship, activity, and levels of stress response to researchers and climate. From this study I found that researchers as well as abiotic effects influence the probability of voiding, a possible stress induced behavior in desert tortoises. Additionally, we found that tortoise activity and survival is constrained by winter precipitation and habitat types. Further research is needed on proximate mechanisms of wind turbines (noise and vibration) and their effects on desert tortoise behavior.
40

Možnosti určení geografického původu živočišných a rostlinných produktů pomocí stabilních izotopů kyslíku, vodíku a uhlíku. Izotopový signál keratinu krunýře želv / The possibilities of determining the geographic origin of plant and animal products by means of stable isotopes of oxygen, hydrogen and carbon. Isotope signature in keratin of tortoise´s shell

DRTINOVÁ, Martina January 2011 (has links)
This biological study is focused on the possibility of using stable isotope analyses to determine the geographic origin of plants and mainly animals especially tortoises. In the experiment nineteen tortoises were divided into two groups which were fed by isotopically different food and water for one year. The samples of keratin from their shells were collected before and after the experiment. Then the samples were analysed for the ratio of particular isotopes using isotope ratio mass spectrometry.

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