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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.
21

Determinação de pesticidas organoclorados em tecidos de tartarugas-verdes (Chelonia mydas) provenientes da costa sudeste do Brasil: estudo da ocorrência em animais com e sem fibropapilomatose / Determination of organochlorine pesticides in tissues of green turtles (Chelonia mydas) from the southeastern coast of Brazil: study of the occurrence in animals with and without fibropapillomatosis

Angelica Maria Sanchez Sarmiento 27 September 2013 (has links)
O aumento das intervenções antropogênicas, nos âmbitos marinho e costeiro representa grande risco aos ecossistemas de suporte de numerosas populações de animais como as tartarugas marinhas. Desequilíbrios no balanço ecológico desses habitats afetam negativamente a sobrevivência de quelônios de longa vida, como a Chelonia mydas, seriamente ameaçada de extinção. As ameaças à espécie incluem captura incidental por pesca, doenças e degradação dos habitats de alimentação e nidificação. Uma das principais doenças é a fibropapilomatose (FP) ou Green Turtle Fibropapiloma Disease (GTFD), afecção tumoral e de caráter infeccioso que acomete predominantemente espécimes juvenis. Numerosas hipóteses têm surgido a respeito da etiologia da doença, mas ainda nada é conclusivo. Contudo existe o consenso de que a etiologia da mesma seja \"multifatorial\" envolvendo um α-herpesvírus como agente etiológico primário e a participação de diversos co-fatores genéticos, nutricionais e ambientais. No Brasil a prevalência média de FP en C. mydas varia conforme a região, existindo localidades nas quais não há registro da doença. O aumento da prevalência da FP tem sido implicada à degradação dos habitats marinhos, relacionado por sua vez a contaminantes ambientais como os organoclorados e seus metabólitos. Estes compostos caracterizam-se por serem altamente persistentes, bioacumulando e biomagnificando no ambiente marinho através do tempo. Além disso, são conhecidos por causarem inúmeros efeitos na saúde, interferindo na imunidade do indivíduo e favorecendo a manifestação de doenças, inclusive sendo apontados como agentes carcinogênicos. No presente trabalho foi desenvolvida uma técnica de extração e purificação baseada no método QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para monitoramento pela cromatografia gasosa com captura de elétrons (GC-μECD) dos agrotóxicos clorados: α-BHC, β-BHC, Heptacloro, Dicofol, α-Endosulfan, β-endosulfan, Sulfato endosulfan, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE e Mirex nos tecidos adiposo e hepático de 64 tartarugas-verdes juvenis (Cumprimento Curvo da Carapaça - CCC = 38,68±5,41cm) acometidas ou não pela FP (24 com FP vs. 40 sem FP), espécimes que vieram a óbito por captura incidental em redes de pesca ou foram encontradas encalhadas nas praias de Ubatuba/SP, Praia Grande/SP e Vitória/ES. Objetivou-se esclarecer possíveis correlações das suas concentrações com variáveis como sexo, tamanho (CCC), índice de condição corporal (ICC), severidade; índice de fibropapilomatose (FPI) e escore de fibropapilomatose (FPS) e ocorrência da doença em algumas localidades da região sudeste do país com diferentes taxas de prevalência da FP, na tentativa de inferir o papel dos mesmos na patogenia desta afecção. Foi observada correlação significativa entre a porcentagem lipídica entre as amostras dos tecidos adiposo e hepático, assim como entre a concentração total de organoclorados (ΣOCS) nos tecidos adiposo e hepático. Embora observadas algumas diferenças na presença ou ausência de alguns contaminantes, estas foram dispersas e não determinantes, ou seja, não permitiram estabelecer um padrão em relação aos diferentes fatores do histórico individual. Não foram encontradas diferenças significativas entre a ΣOCS para ambos os tecidos, em relação ao sexo do animal ou localidade, que permitissem inferir alguma relação entre o grau de contaminação e a variação regional da prevalência da FP. Também não foi possível identificar correlações significativas das concentrações dos poluentes em relação à presença da FP nem entre o FPI e o FPS e a ΣOCS nos tecidos adiposo e hepático. Tampouco foi possível identificar correlações significativas entre o ICC ou CCC e a ΣOCS. Os resultados deste trabalho apresentam um registro temporal do perfil de contaminação nas tartarugas-verdes de vida livre da costa sudeste, confirmando a biodisponibilidade de OCs nas diferentes regiões avaliadas. Embora não tenha sido encontrada uma correlação direta entre a concentração de OCs e a Fibropapilomatose, este estudo demonstra que as tartarugas verdes oriundas da costa sudeste do Brasil estão expostas a níveis significativos de pesticidas organoclorados os quais poderiam ter algum papel na etiologia multifatorial da doença. Estes contaminantes ambientais podem agir afetando a taxa de prevalência de FP, agindo possivelmente como agentes imunossupresores ou através da genotoxicidade e promoção tumoral. Estudos futuros serão desenvolvidos para melhor caracterizar a ação dessas substâncias e seus efeitos nas tartarugas marinhas e para esclarecer como outros fatores podem influenciar esses resultados. / The increase of anthropogenic impacts on both marine and coastal environments is threatening the ecosystems of numerous animal populations, including sea turtles. Disturbances in the ecological balance of these habitats negatively affect the survival of longlived chelonids such as green turtles (Chelonia mydas), which are already considered endangered. Threats to this species include incidental capture by fisheries, habitat degradation of nesting and feeding areas, and diseases. One of the most relevant diseases is fibropapillomatosis (FP) or Green Turtle Fibropapilloma Disease (GTFD), an infectious tumoral disease that predominantly affects juveniles. Numerous hypotheses have been proposed to explain this diseases aetiology, and while none has been conclusively demonstrated there is a consensus that it is multifactorial and involves a -herpesvirus as the primary etiologic agent along with genetic, nutritional and environmental cofactors. The prevalence of FP in C. mydas in Brazil varies among regions, with locations in which the disease remains unreported. Prevalence has been correlated to the degree of degradation of marine habitats, which in turn is related to the presence of environmental contaminants such as organochlorines and their metabolites. These compounds are difficult to break down and persist, bioaccumulate and biomagnify in marine environments over long periods of time. They are also known to produce numerous health effects in the organisms in which they accumulate, hampering immunity and favouring the manifestation of opportunistic disease, with some of these compounds being also carcinogens. In this study we developed extraction and purification technique based on the QuEChERS method (Quick, Easy, Cheap, Effective, Rugged and Safe) and used gas chromatography with electron capture (GC-μECD) to detect and quantify organochlorine (α-BHC, β-BHC, Heptachlor, Dicofol, α-endosulfan, β-endosulfan, Endosulfan sulphate, pp\' -DDD, op\' -DDD, pp\' -DDE, op\' -DDE, and Mirex) in adipose and hepatic tissue samples from 64 juvenile green sea turtles [Curved Carapace Length - CCL = 38.68 ± 5.41 cm] affected or not by FP (24 with FP vs. 40 without FP). These specimens died due to incidental capture by fishing nets or were found dead on beaches of Southeast Brazil: Ubatuba / SP, Praia Grande / SP and Vitória / ES. Aiming to clarify the role of the organochlorines in the pathogenesis of FP, we attempted to establish correlations between the concentration of these compounds and variables such as sex, size (CCL), Body Condition Index (BCI) and disease severity [fibropapillomatosis index (FPI) and fibropapillomatosis score (FPS)], and local FP prevalence. A significant correlation was observed between the lipid percentage of adipose and hepatic samples, as well as between adipose and hepatic organochlorine total concentrations (ΣOCS). Although some differences were observed regarding the presence or absence of contaminants in relation to characteristics of the individual history, it was not possible to establish patterns that reflected biological significance. For both adipose and hepatic tissues, no significant differences were found in the ΣOCS with regards to individual sex or capture locality that would allow inferring relationships between the individual contamination levels and the regional variation on the prevalence of FP. It was also not possible to identify significant relationships between each pollutant concentration in the adipose or hepatic tissue and the presence of FP. No correlation was observed between ΣOCS in adipose or hepatic tissues and FPI, FPS, BCI and CCL. The results provide a contamination profile of free-ranging green turtles of the southeast coast during the study period, confirming the bioavailability of OCs in the different locations evaluated. Although a direct correlation between the concentration of OCs and fibropapillomatosis was not found, this study demonstrates that green turtles from the southeast coast of Brazil are exposed to significant levels of organochlorine pesticides that could play a role in the multifactorial etiology of the disease. These contaminants may affect the prevalence of FP, possibly acting as immunosuppressive agents or through genotoxicity and tumor promotion. Future studies will be conducted to better characterize the role of these substances and their effects on sea turtles and to clarify how other factors that may influence their impacts.
22

Detecção e quantificação de alguns elementos químicos inorgânicos em sangue e tecidos de tartarugas-verdes - Chelonia mydas (Linnaeus, 1758) - da costa brasileira: possível correlação com a fibropapilomatose / Detection and quantification of selected inorganic chemical elements in blood and tissue samples from green turtles Chelonia mydas (Linnaeus, 1758) from the Brazilian coast: possible correlation with fibropapillomatosis

Fabiola Eloisa Setim Prioste 30 March 2016 (has links)
A fibropapilomatose é uma doença multifatorial em tartarugas marinhas caracterizada por tumores cutâneos benignos. O surgimento da doença é atribuído à associação do Chelonid herpesvirus 5 (ChHV-5), à genética e à fatores ambientais. A tartaruga-verde (Chelonia mydas) é a espécie mais acometida pela doença, sendo esta uma das maiores ameaças à sua sobrevivência. Este estudo teve por objetivo detectar e mensurar seis elementos químicos inorgânicos: Arsênio (As), Cádmio (Cd), Chumbo (Pb), Selênio (Se), Zinco (Zn) e Mercúrio (Hg) em sangue de tartarugas-verdes (Chelonia mydas) capturadas vivas e tecidos (baço, rins, fígado, glândula de sal, musculatura esquelética e tecido ósseo) de necropsias realizadas em indivíduos encontrados mortos. Quatro localidades da costa brasileira foram amostradas: Almofala CE; Fernando de Noronha PE; Vitória ES e Ubatuba SP. Foram colhidas 233 amostras de sangue e 488 amostras de tecido entre março de 2012 e outubro de 2015. As amostras foram analisadas em um espectrômetro de massas com plasma indutivamente acoplado (ICP-MS). Os resultados das análises de sangue apontaram Fernando de Noronha como um possível grupo controle para estudos desta ordem. As e Se foram encontrados em Fernando de Noronha em níveis séricos muito baixos. Tartarugas-verdes das outras três localidades estudadas apresentaram uma diminuição desses elementos quando com sinais de FP, ao mesmo tempo em que apresentaram concentrações maiores de algum elemento químico tóxico, como Pb e Hg. Quanto aos resultados obtidos com amostras teciduais, as tartarugas-verdes com sinais de FP apresentam menores concentrações de As e Se em todos os órgãos analisados, ao mesmo tempo que apresentam maior concentração de Pb em fígado, rins e ossos / Fibropapillomatosis is a multifactorial disease of sea turtles characterized by benign cutaneous tumors. The development of this disease is attributed to the association of Chelonid herpesvirus 5 (ChHV-5), to genetics and environmental factors. The green turtle (Chelonia mydas) is the species most affected by fibropapillomatosis, one of the biggest threats to the survival. The aim of this study was to detect and quantify six inorganic chemical elements: Arsenic (As), Cadmium (Cd), Lead (Pb), Selenium (Se), Zinc (Zn) and Mercury (Hg) in blood samples of green turtles trapped alive, and tissue samples (spleen, kidneys, liver, salt glands, skeletal muscles and bone tissue) collected during necropsies of carcasses. The samples was collected in four different locations of the Brazilian coast: Almofala Ceará; Fernando de Noronha Pernambuco; Vitória Espírito Santo e Ubatuba São Paulo. We collected 233 blood samples and 488 tissue samples between March 2012 and October 2015. Samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS) techniques. The results of the blood analyses indicated Fernando de Noronha as a possible control group for studies of this nature. As and Se were observed in Pernambuco (Fernando de Noronha) in very low blood levels. Green turtles from the three other locations presented decreased levels of the same elements in cases with signs of FP, while presenting higher concentrations of some of the toxic chemical elements, such as Pb and Hg. The results obtained from tissue samples showed that green turtles with signs of FP present lower As and Se in all analysed organs, and higher [Pb] in liver, kidneys and bone tissues
23

Ecologia, prevalência e caracterização molecular de Chelonid fibropapilloma-associated herpesvirus (CFPHV) em Tartarugas-Verdes (Chelonia mydas) em áreas da costa brasileira / Ecology, prevalence and molecular characterization of Chelonid fibropapilloma-associated herpesvirus (CFPHV) in Chelonia mydas of Brazilian coast areas

Marco Aurélio Gattamorta 03 February 2016 (has links)
Os herpesvírus são normalmente adaptados a um único grupo de hospedeiros, e esta associação parasita-hospedeiro está ligada à sua seleção e coevolução. Estes agentes podem causar infecções latentes, onde normalmente o vírus não se replica. Durante o ciclo lítico, no entanto, outras células são infectadas e liberam partículas virais capazes de infectar outros indivíduos. O CFPHV (Chelonid fibropapilloma-associated herpesvirus) tem sido apontado como principal agente infeccioso ligado a fibropapilomatose em tartarugas-marinhas. A doença caracteriza-se por uma proliferação cutânea benigna mas que, dependendo da sua severidade, pode comprometer a sobrevivência do indivíduo afetado, sendo por isso apontada como importante ameaça a conservação de tartarugas-marinhas, particularmente de tartarugas verdes (Chelonia mydas), a principal espécie acometida pela doença. Alguns aspectos da biologia do CFPHV e sua relação com as tartarugas verdes foram estudados no presente trabalho. Primeiramente, a capacidade deste agente em se disseminar pelo ambiente e infectar outros indivíduos, e as possíveis vias envolvidas nesta dispersão. Em seguida, avaliou-se os possíveis tecidos em que o herpesvírus pode estabelecer a infecção latente. Por fim, determinou-se a prevalência de indivíduos de Chelonia mydas infectados pelo CFPHV em duas áreas de alimentação (Ubatuba-SP e Vitória-ES) e em uma áreas mista - de alimentação e reprodução (Fernando de Noronha-PE). No primeiro estudo, observou-se que a prevalência de CFPHV nas amostras de secreções de Chelonia mydas variou entre 0%, no Espírito Santo, a 25%, em São Paulo. Os haplótipos afetados foram CMA-3 e CMA-8, e a variante viral encontrada não havia sido detectada anteriormente no Brasil, mas possui elevada similaridade com vírus provenientes do Golfo da Guiné e de Porto Rico. Os resultados sugerem que estes vírus podem ser transmitidos por secreções e também circular entre diferentes regiões. No segundo estudo, detectou-se a presença de CFPHV no cérebro de 5 animais necropsiados e também na pele e em lesões fibropapilomatosas. Em um dos animais foi detectada a presença de uma única variante de CFPHV no cérebro, pele e tumores. Esta variante ainda não havia sido detectada no Brasil e apresentou 100% de identidade com a variante detectada nas secreções. Para avaliar a relação entre haplótipos e variantes virais, o terceiro estudo determinou a prevalência de CFPHV em pele e tumores de 136 indivíduos - 9,56% de indivíduos sadios apresentavam o agente em tecido epitelial e 45,58% dos animais foram positivos para CFPHV, quando considerados também animais com fibropapilomatose. Duas novas variantes de herpesvírus foram encontradas: Var. 7, em Ubatuba-SP e Vitória-ES e Var. 8, em Vitória-ES. Não houve associação entre uma variante viral e um haplótipo. Os resultados observados permitem apontar que o CFPHV pode estabelecer infecções latentes; o vírus pode \"migrar\" entre diferentes regiões, junto com seus hospedeiros; partículas virais podem ser liberadas por secreções; duas novas variantes foram identificadas. Altas taxas de substituição de nucleotídeos em CFPHV podem indicar o surgimento das variantes destas áreas, mas a alta similaridade entre as variantes detectadas e àquelas de Porto Rico e Golfo da Guiné sugerem também a entrada de novas variantes na costa brasileira. / Herpesviruses are usually adapted to a single group of hosts, and this host-parasite association is linked to its selection and co-evolution. These agents can cause latent infections, where the virus usually does not replicate. During the lytic cycle, however, other cells are infected and release viral particles capable of infecting other individuals.The CFPHV (Chelonid fibropapilloma-associated herpesviru) has been indicated as the main infectious agent linked to fibropapillomatosis on sea turtles. The disease is characterized by a benign skin proliferation, but, depending on its severity, can compromise the survival of the affected individual, therefore considered an important threat to the conservation of sea turtles, especially green turtles (Chelonia mydas), the main species affected by the disease. Some aspects of the CFPHV biology and its relation to green turtles were studied in this work. Firstly, the ability of this agent to spread in the environment and infect other individuals, and the possible pathways involved in this dispersion. Then, potential tissues wherein the herpesvirus can establish latent infection were assessed. Finally, we determined the prevalence of Chelonia mydas individuals infected by CFPHV in two feeding areas (Ubatuba-SP and Vitória-ES) and in a mixed area of feeding and reproduction (Fernando de Noronha-PE). In the first study, it was observed that the prevalence of CFPHV in samples of Chelonia mydas secretions ranged from 0% in Espírito Santo, to 25% in São Paulo. Affected haplotypes were CM-A3 and CM-A8, and viral variant found had not been previously detected in Brazil, but it is significantly similar to viruses found in the Gulf of Guinea and Puerto Rico. The results suggest that these viruses can be transmitted by secretions and can also circulate among different regions. Considering the low maintenance of the agent within the environment, they are probably brought by individuals with the latent virus, being capable of releasing viral particles during the herpesvirus replication cycle. In the second study, the presence of CFPHV was detected inside the brain of 5 necropsied animals, besides the detection of the virus on the skin and fibropapillomatosis lesions. In one of the animals, it was possible to characterize the CFPHV and the presence of a single viral variant inside the brain, tumors and on the skin of the same animal was detected. This variant had not yet been detected in Brazil and showed 100% identity with the variant detected in secretions. These results indicate that the virus may establish a latent infection in nerve tissue. To evaluate the relationship between haplotypes and viral variants, the third study determined the prevalence of CFPHV on skin and tumors of 136 individuals - 9.56% of healthy individuals showed the agent in epithelial tissue and 45.58% of the animals were positive for CFPHV, when also considered animals with fibropapillomatosis. Two new variants of the herpesvirus were found, Var. 7 in Ubatuba-SP and Vitória-ES and Var. 8 only in Vitória-ES. C. mydas individuals of different haplotypes were infected, and there was no association between a viral variant and a haplotype. The observed results permitted to point that CFPHV can establish latent infections in Chelonia mydas; the virus can \"migrate\" among different regions, along with its hosts; viral particles can be released by secretion; viral variants previously detected were not found in these areas, but two new variants were detected. The high nucleotide substitution rates observed in CFPHV may indicate the emergence of these variants in these areas, but the high similarity among the detected variants and those identified in Puerto Rico and Gulf of Guinea also suggest the entry of new variants into the Brazilian coast.
24

Ocorrência de Pesticidas Organoclorados e Bifenilos Policlorados em tartarugas marinhas Chelonia mydas / Occurrence of organochlorine pesticides and polychlorinated biphenyls in sea turtles Chelonia mydas

Josilene da Silva 25 June 2009 (has links)
Os compostos organoclorados (OCs), como pesticidas e bifenilos policlorados (PCBs), são persistentes, tóxicos e amplamente distribuídos através do transporte atmosférico e correntes oceânicas. Poucos são os estudos realizados de OCs em tartarugas, sendo que nenhum foi realizado na costa brasileira. A Chelonia mydas é a maior tartaruga marinha de carapaça dura, que se distribue por todos os oceanos, nas zonas de águas tropicais e subtropicais. O presente trabalho visa verificar a ocorrência de organoclorados na espécie C. mydas, bem como sua possível relação com algum tipo de alteração morfológica ou fisiológica. Foram coletadas amostras de gordura, fígado, rim e músculo em 27 espécimes juvenis do litoral de Ubatuba, São Paulo. Os organoclorados foram extraídos com solventes orgânicos e o extrato foi purificado com ácido concentrado. A identificação e quantificação dos PCBs e pesticidas foram realizadas em cromatógrafo a gás com espectrômetro de massas e com detector de captura de elétrons, respectivamente. Os pesticidas organoclorados não foram detectados em nenhuma amostra. As concentrações de PCBs totais em peso úmido foram de: <1,6 48,9 ng.g-1 em gordura, <1,6 17,4 ng.g-1 no fígado e <1,6 9,2 ng.g-1 no rim. Os baixos níveis encontrados estão relacionados principalmente a sua dieta alimentar, uma vez que a C. mydas é basicamente herbívora, e ao local de coleta, que é uma região não industrializada. / Organochlorine compounds, such as pesticides and polychlorinated biphenyls (PCBs), are persistent, toxics and widely distributed due to the atmospheric transport and oceanic currents. Few studies have reported the occurrence of these compounds in turtles, but none from the Brazilian Coast. Chelonia mydas is the biggest marine turtle with hard carapace that extends throughout tropical and subtropical seas around the world. The present study aims to assess the concentrations of organochlorines in the C. mydas as well as any relationship with morphological or physiological variations. Fat, liver and kidney samples were collected from 27 juvenile specimens found dead in Ubatuba Coast, São Paulo State. Organochlorine were extracted with organic solvents and the extracts were purified with concentrated acid. PCBs and pesticides were identified and quantified using a gas chromatograph with mass spectrometer and with electron capture detector, respectively. Pesticides were not detected in any sample analyzed. PCBs concentrations in wet weight were: <1.6 48.9 ng.g-1 in fat, <1.6 17.4 ng.g-1 in liver and <1.6 9.2 ng.g-1 in kidney. The low levels detected are related, especially, to the feeding habits of the species since C. mydas is mainly herbivore, and to a non industrialized sampling area.
25

Identificação de sequências gênicas de Chelonid alphaherpesvirus 5 (ChHV5) em tecidos tumorais caracterizados histologicamente e secreções de Chelonia mydas capturadas no litoral norte do Estado de São Paulo no período de 2001 a 2012. / dentification of Chelonid alphaherpesvirus 5 (ChHV5) gene sequences in tumor tissues histologically characterized and secretions from green turtles Chelonia mydas captured off the coast of São Paulo State in the period 2001-2012.

Telma Alves Monezi 30 September 2016 (has links)
A fibropapilomatose é uma neoplasia caracterizada pela formação de múltiplos tumores que acomete, mais frequentemente, a espécie de tartaruga marinha Chelonia mydas. Estudos recentes apontam o Chelonid herpesvirus 5 (ChHV5) como o provável agente etiológico dessa doença, embora a associação com ambientes antropogenicamente alterados parecem contribuir para o desenvolvimento da doença. Nesse estudo, biópsias de tumores e secreções de tartarugas verdes capturadas no litoral do Estado de São Paulo, Brasil, foram submetidas a análises histológicas e moleculares visando detectar e caracterizar ChHV5. Em 45,5 % dos casos, os achados histopatológicos revelaram células epiteliais balonizantes com corpúsculos de inclusão intranucleares. ChHV5 foram detectados nas biópsias de pele e oculares dos animais e em secreções oculares e saliva por PCR. A análise das sequências parciais do gene da polimerase do ChHV5 detectadas revelou duas sequências gênicas distintas entre si. A análise filogenética indicou que as amostras brasileiras são similares às amostras de ChHV5 do grupo filogeográfico do Atlântico, compartilhando o mesmo clado que amostras provenientes do Golfo da Guiné e de Porto Rico, sugerindo um possível fluxo dos vírus entre essas três regiões. / Fibropapillomatosis is a neoplastic disease characterized by the formation of multiple tumors affecting different species of sea turtles and, most often, Chelonia mydas. Recent studies indicate that Chelonid herpesvirus 5 (ChHV5) is the etiological agent of this disease, though its association with anthropogenically altered environments also appears to contribute to disease expression and tumor formation. In this study, tumor biopsy and secretions from green turtles captured off the coast of São Paulo State, Brazil, were used in histological and molecular analyses to detect and characterize ChHV5. In 45.5 % of cases, the tumor histopathological findings revealed ballooning degeneration with intranuclear inclusion bodies. ChHV5 was detected using polymerase chain reaction on the animals skin, ocular tumor biopsies, and ocular and oral secretions. The analysis of the detected ChHV5 sequences revealed two distinct genetic sequences together. Phylogenetic analysis indicated that Brazilian samples were similar to ChHV5 samples described for the Atlantic phylogeographic group and are therefore part of the same clade as the Gulf of Guinea and Puerto Rico samples. This similarity suggests a possible flow of the virus between these three regions.
26

INFLUENCE OF UV LIGHT ON VITAMIN D AND IMMUNE FUNCTION OF GREEN (CHELONIA MYDAS) SEA TURTLES WITH FIBROPAPILLOMATOSIS

Unknown Date (has links)
Green sea turtles (Chelonia mydas) are an endangered species prone to a debilitating disease called fibropapillomatosis (FP). The aim of this study was to determine the influence of UV light on vitamin D levels and immune function in juvenile green sea turtles with FP. Phagocytosis, plasma vitamin D levels and viral load of ChHV5 were measured for FP- and FP+ turtles kept at the Gumbo Limbo Nature Center (GLNC) and for turtles caught at the St. Lucie power plant. Turtles kept at GLNC were housed in tanks exposed to varying amounts of UV light. Turtles brought into GLNC had lower phagocytosis compared to turtles at the St. Lucie power plant. Individuals exposed to greater UV light had higher plasma vitamin D levels and a more successful recovery. The results of this project will provide rehabilitation facilities with a mechanism to improve the recovery of animals with this disease. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
27

Sex Ratios Of Juvenile Green Turtles (chelonia Mydas) In Three Developmental Habitats Along The Coast Of Florida

Sanchez, Cheryl 01 January 2013 (has links)
The concept of temperature dependent sex determination (TSD) has been somewhat of an evolutionary enigma for many decades and has had increased attention with the growing predictions of a changing climate, particularly in species that are already threatened or endangered. TSD taxa of concern include marine turtles, which go through various life stages covering a range of regions. This, in turn, creates difficulties in addressing basic demographic questions. Secondary sex ratios (from life stages post-hatchling) were investigated by capturing juvenile green turtles (Chelonia mydas), 22.6-60.9 cm in straight carapace length (SCL), from three developmental areas along the east coast of Florida (a region known to have important juvenile aggregations) by analyzing circulating testosterone levels. All three aggregations exhibited significant female biases with an overall ratio of 3.2:1 (female: male). The probability of a turtle being female increased as the size of the individual decreased. Ratios obtained in this study were slightly less female-biased, but not significantly different, than those observed in the late 1990s. However, they were significantly more biased than those found in a late 1980s pilot study. The shift to significantly female-biased ratios may be beneficial to a recovering population, an evolutionary adaptation, and is common among juvenile aggregations. A more skewed female bias in smaller size classes may be indicative of recent, warmer periods during incubation on the nesting beaches. This female bias could become more exaggerated if temperatures meet future climate warming predictions.
28

DISCOVERING SEAGRASS BLUE CARBON RESOURCES IN THE RED SEA BY GREEN TURTLE Chelonia mydas TRACKING

Mann, Hugo F. 27 November 2022 (has links)
Seagrass is a valuable and important habitat, providing services such as coastal protection, supporting fisheries, and carbon sequestration. However, it is challenging to map accurately, as remote sensing has limits to how deep in the water column it can penetrate, and uncertainties such as distinguishing between algae and seagrass. Seagrass can exist at depths of theoretically 90 m deep in ultraoligotrophic waters, meaning that there is much of this habitat that cannot be mapped by remote sensing. Green turtles are an ideal candidate to help find seagrass blue carbon resources in the Red Sea. They go through an ontogenetic dietary shift to become almost completely herbivorous, and have a high fidelity to foraging sites. In this study we aim to assess the use of green turtles Chelonia mydas in discovering seagrass blue carbon. We use telemetry from 53 turtles tagged over 2018, 2019, and 2021 to map their foraging areas. 50 out of the 53 (94.34%) foraging sites had not been visited by previous seagrass studies in the Red Sea. We visited 18 locations in 14 of these foraging sites to ground truth them, and all 14 foraging sites (100%) had seagrass present. Comparatively, 18 out of 30 sites where seagrass was indicated by the remote sensing-based Allen Coral Atlas showed no seagrass. The turtles were seen to favour travelling shorter distances, thus it will be necessary to expand the area of tagging in order to achieve complete coverage of the Red Sea. Approximately 1/3 of the visited sites were deeper than 8 m, and so out of range of remote sensing, showing that considerable blue carbon resources may be discovered with the use of turtles. Samples were taken for carbon stock estimation from the ground truthed sites. A mean carbon stock of 4.89 ± 0.83 kg Corg m-2 was estimated for 1 m depth sediment. In the future it is important to develop methods for mapping the surface areas of the deep and inaccessible seagrass habitats that the turtles discover.
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Estudo da dieta de juvenis de Chelonia mydas (Linnaeus, 1758) no litoral de Ubatuba, SP

Faria, Adriana Fonseca de 17 March 2010 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-09-22T11:26:45Z No. of bitstreams: 1 adrianafonsecadefaria.pdf: 930419 bytes, checksum: 95f7e760beeded23d0bdca1ba20b6294 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-09-26T20:28:21Z (GMT) No. of bitstreams: 1 adrianafonsecadefaria.pdf: 930419 bytes, checksum: 95f7e760beeded23d0bdca1ba20b6294 (MD5) / Made available in DSpace on 2016-09-26T20:28:21Z (GMT). No. of bitstreams: 1 adrianafonsecadefaria.pdf: 930419 bytes, checksum: 95f7e760beeded23d0bdca1ba20b6294 (MD5) Previous issue date: 2010-03-17 / Um grande número de juvenis da espécie Chelonia mydas (Linnaeus, 1758) utiliza o litoral norte do Estado de São Paulo como área de alimentação, com grande ocorrência no Município de Ubatuba. Existem poucos trabalhos sobre a dieta desta espécie no Brasil. Por esta razão, o presente estudo tem como objetivo determinar a dieta, além de qualificar e quantificar os itens alimentares ingeridos por esses espécimes. Para a determinação da dieta, 20 conteúdos estomacais de juvenis de C. mydas foram analisados. Estes animais foram encontrados mortos ao longo da costa de Ubatuba e encaminhados à equipe do Projeto TAMAR/ICMBio. Os dados biométricos dos animais coletados indicam que todos os indivíduos podem ser considerados juvenis, pois apresentaram comprimento curvilíneo da carapaça (CCC) entre 35 e 60 cm e peso entre 7 e 8 Kg. Dos itens presentes no conteúdo estomacal destacaram-se os vegetais (algas e gramas marinhas) com 93,64% do total, seguido de material antrópico com 4,71% e animal com 1,65%. As algas da família Rhodophyta foram as mais abundantes onde constatou-se um maior volume para Pterocladiella capillacea (44,5V%) e Chondracanthus acicularis (42,3V%). Do material antrópico ingerido o plástico mole foi o mais abundante (54,3%) e o nylon o mais freqüente (45%). Com base nestes resultados salienta-se a importância de programas de conservação para esta espécie em áreas de alimentação. / A large number of Chelonia mydas (Linnaeus, 1758) young utilizes the northern coast of São Paulo state as feeding grounds. Great parts of these areas are located in Ubatuba. At this moment, there is a few data on C. mydas feeding habits in Brazil. Because of that, the objective of this study was to determine the C. mydas diet, and qualify and quantify its diet items. Twenty stomachs of C. mydas young individual were analyzed. These animals were found dead along Ubatuba coast and sent to Project TAMAR/ICMBio. All individuals were considered young because the curved carapace length was between 35 and 65, and the weight was between 7 and 8 Kg. Vegetables were the most frequent item found in the stomachs (seaweed and marine grass) representing 93,64% of the total, followed for anthropic material (4,71%) and animal material (1,65%). The seaweed family of Rhodophyta was the most abundant with Pteocldiella capillacea and Chodracanthus acicularis having the largest volumes, 44,5% and 42,3% respectively. Among the anthropic material, soft plastic was the most abundant (53%) and nylon the most frequent (45%). This results shows the importance of conservation programs for C. mydas among your feeding areas.
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Percepção e interação de comunidades caiçaras do complexo estuarino-lagunar de Iguape-Cananéia, SP, Brasil, com tartarugas marinhas / Perception and interaction of caiçara communities from Iguape-Cananéia-Lagoon Complex, SP, Brazil, with sea turtles.

Gusmão, Juliana São Pedro 18 November 2013 (has links)
Made available in DSpace on 2016-06-02T19:26:23Z (GMT). No. of bitstreams: 1 GUSMAO_Juliana_2013.pdf: 2002037 bytes, checksum: 764c92fab171e138eea762ca82c8ad4d (MD5) Previous issue date: 2013-11-18 / Financiadora de Estudos e Projetos / The Iguape-Cananéia Estuarine-Lagoon Complex has been described as an area for feeding and development of young sea turtles of the Chelonia mydas (green sea turtle) species, besides having recorded the incidence of other marine turtle species present at the Brazilian coast (Caretta caretta, Lepidochelys olivacea, Dermochelys coriacea and Eretmochelys imbricata). The region also presents several caiçara (population from coastal regions) nucleuses which have small-scale fishing as their main source of income, making important to analyze existing interactions between fishermen and sea turtles. The objective of the present study was to describe the interaction of the caiçara communities of Pedrinhas and Pontal de Leste with sea turtles, and the interaction between sea turtles and the artisanal gillnetting, from the fishermen s perspective. Field researches were performed using semi-structured interviews via Snow Ball technique, enabling the identification of the key informers by their peer s recognition. The results showed that the caiçara community of Pontal de Leste, more isolated from the urban centers and having fishing as exclusive activity, presented greater presence of sea turtles in its culture, as well as higher nutritional dependency from sea turtle meat when climate conditions render fishing impossible for long periods of time. At the Pedrinhas community, as it is closer to urban centers and as it has alternative income activities due to tourism, the presence of the sea turtle in the local culture resides mainly at the memories of the older interviewed community members. In both communities knowledge gaps were verified, which could be clarified with educational actions, and the importance of gillnetting for the caiçara and the negative impact it may cause to sea turtles were also verified, being thus vital, the execution of new studies which shall enable the understanding of the magnitude of such interaction. The results obtained aim at generating information for conservation plans so as to minimize the mortality of sea turtles, protecting cultural practices of such communities; thereby, educational activities and management guidelines were proposed, aiming at integrating the political management of natural resources and conservation strategies with the conduct of the local traditional community. / O Complexo Estuarino-Lagunar de Iguape-Cananéia foi descrito como uma área de alimentação e desenvolvimento para juvenis de tartarugas marinhas da espécie Chelonia mydas (tartaruga-verde), além de ter registrado a ocorrência das outras espécies de tartarugas marinhas presentes na costa brasileira (Caretta caretta, Lepidochelys olivacea, Dermochelys coriacea e Eretmochelys imbricata). A região apresenta também vários núcleos caiçaras que têm na pesca artesanal sua principal fonte de renda, o que torna, importante, avaliar as interações existentes entre os pescadores e as tartarugas marinhas. O objetivo deste estudo foi descrever a interação das comunidades caiçaras de Pedrinhas e Pontal de Leste, com as tartarugas marinhas e destas com a pesca de emalhe artesanal, sob a perspectiva dos pescadores. Foram realizadas pesquisas de campo utilizando entrevistas semi-estruturadas através da técnica Bola de Neve , que possibilitou identificar os informantes-chave pelo reconhecimento por seus pares. Os resultados evidenciaram que a comunidade caiçara de Pontal de Leste, mais isolada dos centros urbanos e tendo como única atividade a pesca, apresentou maior presença das tartarugas marinhas em sua cultura, assim como maior dependência nutricional da carne de tartaruga marinha quando as condições climáticas impossibilitam a pesca por longos períodos. Na comunidade de Pedrinhas, por estar próxima aos centros urbanos e ter atividades alternativas de renda, devido ao turismo, a presença da tartaruga marinha na cultura local reside principalmente na memória dos entrevistados mais antigos. Em ambas as comunidades evidenciou-se lacunas de conhecimento que poderiam ser esclarecidas com ações educativas, verificou-se também a importância da rede de emalhe para o caiçara e o impacto negativo que esta pode causar às tartarugas marinhas, sendo imprescindível, portanto, a realização de novos estudos que possibilitem compreender a dimensão desta interação. Os resultados obtidos visam gerar informações para planos de conservação de forma a minimizar a mortalidade das tartarugas marinhas, protegendo as práticas culturais dessas comunidades, desta forma, diretrizes de ações educativas e de gestão foram propostas, objetivando integrar a gestão política dos recursos naturais e estratégias de conservação com o comportamento da comunidade tradicional local.

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