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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.
1

Biodiversidade dos helmintos parasitos dos roedores simp?tricos Oligoryzomys nigripes e Akodon spp. (Rodentia: Sigmodontinae), na Mata Atl?ntica / Biodiversity of helminth parasites in the sympatric rodents Oligoryzomys nigripes and Akodon spp. (Rodentia: Sigmodontinae), in the Atlantic Forest, Teres?polis

SIM?ES, Raquel de Oliveira 28 January 2009 (has links)
Made available in DSpace on 2016-04-28T20:15:35Z (GMT). No. of bitstreams: 1 2009 - Raquel de Oliveira Simoes.pdf: 2148721 bytes, checksum: 7408aa4a20471b27145d83c2bea4886a (MD5) Previous issue date: 2009-01-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The objective of this study was to describe the composition and structure of helminthes community comparing the helminthes community component and infracommunity from sympatric rodents Akodon spp. and Oligoryzomys nigripes in the Atlantic Forest and in the different fragments size and the Parque Nacional da Serra dos ?rg?os (PARNA SO reserve. One hundred and fifty-six specimens of Akodon spp. and fifty-seven of Oligoryzomys nigripes were collected in Teres?polis, being 38 rodents in 4 small fragments (30 Akodon spp. and 8 O. nigripes), 58 in 4 medium fragments (43 Akodon spp. and 15 O. nigripes), 87 in 4 large fragments (67 Akodon spp. and 20 O. nigripes) and 30 in PARNASO (16 Akodon spp. e 14 O. nigripes). The stydy was done for two years (2004- 2005). The animals were necropsied and the viscera and cavities examined to helminthes parasites. A total of eighteen helminthes species were collected: 15 from Akodon spp. and12 from O. nigripes. Nine species were common for both rodents. The rodent Akodon spp. showed a higher richness than O. nigripes. A low degree of similarity between the helminthes infracommunities from Akodon spp. and O. nigripes was detected, although these rodents species live in coexistence. The terrestrial and arboreal behavior of O. nigripes and terrestrial behavior of Akodon spp. would determine this difference between both parasite communities. Probably, with the share of soil resource boths species of rodents could disseminate or be infected by the parasite. The prevalence of Stilestrongylus aculeata and mean abundance for Stilestrongylus eta increased, respectively, in small, medium and large fragments in Akodon spp.. The rodent O. nigripes showed high prevalence rate and mean abundance values for Stilestongylus lanfrediae (over 86%) regardless of the fragments size studied. The difference in mean richness for Akodon spp. and O. nigripes in different fragments size and PARNASO were not significant. There were variations between the helminthes infracommunities for the two species of rodent in different fragments size and PARNASO. These differences may also be related to the environmental changes that can produce both positive and negative effects on the transmission of helminthes parasites. / O objetivo deste trabalho foi descrever a composi??o e estrutura da comunidade helm?ntica comparando a comunidade componente e a infracomunidade dos helmintos das popula??es de roedores simp?tricos Akodon spp. e Oligoryzomys nigripes na Mata Atl?ntica e os diferentes tamanhos de fragmentos e a reserva do Parque Nacional da Serra dos ?rg?os (PARNASO). Cento e cinq?enta e seis esp?cimes de Akodon spp. e cinq?enta e sete de O. nigripes foram coletados no munic?pio de Teres?polis, sendo 38 roedores em 4 fragmentos pequenos (30 Akodon spp. e 8 O. nigripes), 58 em 4 fragmentos m?dios (43 Akodon sp p. e 15 O. nigripes), 87 em 4 fragmentos grandes (67 Akodon spp. e 20 O. nigripes) e 30 no PARNASO (16 Akodon spp. e 14 O. nigripes). O estudo foi feito durante dois anos (2004- 2005). Os animais foram necropsiados tendo suas v?sceras e cavidades tor?cica e abdominal examinadas para recupera??o de helmintos parasitos. Um total de 18 esp?cies de helmintos foram coletados: 15 em Akodon spp. e 12 em O. nigripes. Nove esp?cies foram comuns aos dois roedores. O roedor Akodon spp. teve uma maior riqueza parasit?ria do que O. nigripes. Um baixo grau de similaridade entre as infracomunidades de helmintos de Akodon spp. e O. nigripes foi observado, embora sejam esp?cies que coexistam. O comportamento terrestre e arbor?cola de O. nigripes e apenas terrestre de Akodon spp. poderia determinar essa diferen?a entre as duas comunidades de helmintos parasitos. Provavelmente, ao compartilharem os recursos do solo, ambas as esp?cies podem se infectar ou disseminar o parasita. A preval?ncia para Stilestrongylus aculeata e a abund?ncia m?dia para S. eta aumentaram, respectivamente, nos fragmentos pequenos, m?dios e grandes no Akodon spp.. O roedor O. nigripes apresentou elevada taxa de preval?ncia e valores de abund?ncia m?dia para S. lanfrediae (acima de 86%) independente do tamanho dos fragmentos estudados. A diferen?a na riqueza m?dia de Akodon spp. e O. nigripes nos diferentes tamanhos de fragmentos e no PARNASO n?o foi significativa. Houve varia??es entre as infracomunidades de helmintos das duas esp?cies de roedores nos diferentes tamanhos de fragmentos e PARNASO, podendo essas diferen?as estarem relacionadas com as altera??es ambientais causadas pela fragmenta??o que podem produzir tanto efeitos positivos como negativos na transmiss?o dos helmintos parasitos.
2

Composi??o e estrutura das comunidades de metazo?rios parasitos de Aspistor luniscutis e Genidens barbus (Osteichthyes: Ariidae) e Anchoa marinii e A. tricolor (Osteichthyes: Engraulididae) do litoral do estado do Rio de Janeiro, Brasil / Structure and compositon of the metazoan parasite communities of the Aspistor luniscutis and Genidens barbus (Osteichthyes: Ariidae) and Anchoa marinii and A. tricolor (Osteichthyes: Engraulididae) from the coastal zone of the State of Rio de Janeiro, Brazil.

Tavares, Luiz Eduardo Roland 22 February 2006 (has links)
Made available in DSpace on 2016-04-28T20:16:25Z (GMT). No. of bitstreams: 1 Tese doutorado Luiz E R Tavares.pdf: 3698321 bytes, checksum: 88ee3343995b20e18679c2e8c383c32c (MD5) Previous issue date: 2006-02-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Between March 2000 and February 2003 63 specimens of sea catfishes G. barbus and 69 specimens of A. luniscutis and Between October 2001 and July 2003, 103 specimens of anchovies A. tricolor and 95 specimens of A. marinii from the coastal zone of the State of Rio de Janeiro (23?01'S, 43?38 - 44?19'W), Brazil, were necropsied to study their communities of metazoan parasites. Additionally, data obtained from 136 specimens of A. marinii and 115 specimens of E. anchoita, from the coastal zone of Mar del Plata (38?08 S, 57?32 W), Argentine, necropsied between November 1993 and February 1999, and were included in the present analysis. Ecological and community parasitic descriptors were calculated and its possible similarities statistically tested. Ergasilus youngi Tavares & Luque, 2005, parasitic on the gills of sea catfish, Aspistor luniscutis from the coastal zone of the state of Rio de Janeiro, Brazil is described and illustrated. Twenty three species of metazoan parasites were determined, 15 species parasitic in G. barbus and 17 parasitic in A. luniscutis, and 25 species of metazoan parasites from engraulidids were determined. Only P. merus was founded in all host species sample, although other four species were common to both Brazilian and Argentinean samples. The parasite infracommunities of A. luniscutis e G. barbus were characterized by ectoparasite dominance and scarcity of core species. The communities of metazoan parasites of the studied anchovies were characterized by dominance of larval endoparasites. Similarity between parasitic communities of sympatric species of ariid could be explained by habitat overlapping and similar biological behavior, that might expose to the same infective forms. Greater similarity observed between samples belonging to the same locality suggests the influence of ecological factors on the parasitic community structure of these species of engraulidids. / Entre mar?o de 2000 e fevereiro de 2003 foram necropsiados 63 esp?cimes de bagres marinhos G. barbus e 69 esp?cimes de A. luniscutis e entre outubro de 2001 e julho de 2004 foram necropsiados 103 esp?cimes de manjubas de A. tricolor e 95 esp?cimes de A. marinii do litoral do estado do Rio de Janeiro (23?01'S, 43?38 - 44?19'W), Brasil, para o estudo de suas comunidades de metazo?rios parasitos. Adicionalmente, foram inclu?dos na an?lise dados obtidos de 136 esp?cimes de A. marinii e 115 esp?cimes de E. anchoita, provenientes do litoral de Mar del Plata (38?08 S, 57?32 W), Argentina, necropsiados entre novembro de 1993 e fevereiro de 1999. Para cada amostra de hospedeiro foram calculados os descritores ecol?gicos e comunit?rios do parasitismo e suas poss?veis similaridades testadas estatisticamente. Ergasilus youngi Tavares & Luque, 2005, parasita das br?nquias do bagre marinho Aspistor luniscutis do litoral do estado do Rio de Janeiro, Brasil, ? descrita e ilustrada. Foram determinadas 23 esp?cies de metazo?rios parasitos de ar?deos, 15 esp?cies parasitando G. barbus e 17 em A. luniscutis, sendo que nove esp?cies foram comuns ?s duas esp?cies de hospedeiros e determinadas 25 esp?cies de metazo?rios parasitos de engraulid?deos, sendo que apenas a esp?cie P. merus foi encontrado nas quatro amostras de hospedeiros, embora outras quatro esp?cies tenham ocorrido em comum entre amostras brasileiras e argentinas. As infracomunidades parasit?rias de A. luniscutis e G. barbus foram caracterizadas pela domin?ncia de ectoparasitos e escassez de esp?cies centrais. As comunidades parasit?rias das manjubas estudadas foram caracterizadas pela domin?ncia de endoparasitos em est?gio larvar. A similaridade entre as comunidades parasit?rias das esp?cies simp?tricas de ar?deos pode ser explicada em fun??o compartilhamento de h?bitat e similaridade de comportamento biol?gico, que podem favorecer a exposi??o ?s mesmas formas infectantes. A maior similaridade observada entre as amostras da mesma localidade sugere a influ?ncia de fatores ecol?gicos sobre a estrutura das comunidades parasit?rias destas esp?cies de engraulid?deos.
3

Composição e variação espacial na estrutura das comunidades parasitárias de peixes da família anostomidae das Bacias Hidrográficas dos Rios Grande e São Francisco / Composition and space variation in the structure of the parasitary communities of the family fish anostomidae of the Grande and São Francisco Rivers Hydrographic Basins

Silva, Ana Carolina da [UNESP] 12 June 2017 (has links)
Submitted by Ana Carolina da Silva null (anacarolana@hotmail.com) on 2017-07-11T12:59:08Z No. of bitstreams: 1 Tese_Ana_Carolina_da_Silva.pdf: 2050135 bytes, checksum: a296bb77ef0c1d6524f5a9d5d96779c7 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-07-14T15:04:53Z (GMT) No. of bitstreams: 1 silva_ac_dr_jabo.pdf: 2050135 bytes, checksum: a296bb77ef0c1d6524f5a9d5d96779c7 (MD5) / Made available in DSpace on 2017-07-14T15:04:53Z (GMT). No. of bitstreams: 1 silva_ac_dr_jabo.pdf: 2050135 bytes, checksum: a296bb77ef0c1d6524f5a9d5d96779c7 (MD5) Previous issue date: 2017-06-12 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho teve como objetivo o estudo taxonômico e ecológico dos metazoários parasitas de peixes da Família Anostomidae pertencentes às Bacias Hidrográficas do Rio Grande e Rio São Francisco. No total foram coletados 411 exemplares de peixes, dos quais 360 pertenciam à bacia do Rio Grande e 51 da bacia do Rio São Francisco, sendo que 244 (94,16%) e 45 (88,23%), respectivamente, estavam parasitados por alguma espécie de metazoário. Foram identificados os seguintes parasitas: Rhinoxenus arietinus, Rhinoxenus nyttus, Protorhinoxenus prochilodi, Jainus leporini, Tereancistrum parvus, Urocleidodes paradoxus, Urocleidodes naris e Tereancistrum paranaensis; Clinostomum sp. 1 (metacercárias) e Clinostomum sp. 2 (adultos), Procamallanus (Spirocamallanus) inopinatus, Rhabdochona sp., Contracaecum sp. (juvenis), Gamispatulus schizodontis e uma espécie de Isopoda. Não houve correlação do sexo com a abundância parasitária. Algumas espécies de parasitas demonstraram correlação negativa com peso e comprimento padrão dos hospedeiros e abundância parasitária, com exceção de Leporinus macrocephalus (Rio Grande) que demonstrou correlação positiva entre peso, comprimento padrão e abundância parasitária de R. nyttus e P. prochilodi. Os mesmos hospedeiros apresentaram a maior diversidade de parasitas, enquanto a menor diversidade foi observada em Schizodon nasutus coletados no Rio Mogi Guaçu. As espécies de parasitas mais abundantes foram U. paradoxus e J. leporini, porém não foram dominantes. Dentro das localidades, os hospedeiros diferiram entre si quanto à abundância parasitária, com exceção do Rio Pardo onde não houve diferença significativa entres as espécies de peixes coletadas (p>0,05). Os resultados também mostraram diferença significativa (p<0,05) na abundância parasitaria dos hospedeiros analisados nas diferentes localidades. O PERMDISP mostrou diferença significativa (p<0,05) na dispersão parasitaria entre as localidades, exceto entre Rios Grande e Pardo. Leporinus obtusidens apresentou maior diversidade parasitária que L. friderici. Não foi observada declínio de similaridade com o aumento da distância geográfica, ao contrário, constatou-se que a similaridade aumentou com a distância. / The present study had as objective the taxonomic and ecological study of the parasitic metazoan fish of the Anostomidae Family belonging to the Hydrographic Basins of Grande River and São Francisco River. In total, 411 specimens of fish were collected, of which 360 belonged to the Grande River Basin and 51 from the São Francisco River Basin, respectively, 244 (94.16%) and 45 (88.23%) were parasitized by some species of metazoan. The following parasites have been identified: Rhinoxenus arietinus, Rhinoxenus nyttus, Protorhinoxenus prochilodi, Jainus leporini, Tereancistrum parvus, Urocleidodes paradoxus, Urocleidodes naris and Tereancistrum paranaensis; Clinostomum sp. 1 (metacercariae) and Clinostomum sp. 2 (adults), Procamallanus (Spirocamallanus) inopinatus, Rhabdochona sp., Contracaecum sp. (juveniles), Gamispatulus schizodontis and a species of Isopoda. There was no correlation between sex and parasite abundance. Some species of parasites showed negative correlation with host weight and standard length and parasite abundance, except for Leporinus macrocephalus (Grande River), which showed a positive correlation between weight and standard length and parasitic abundance of R. nyttus and P. prochilodi. The same hosts had the highest diversity of parasites, while the lowest diversity was observed in Schizodon nasutus collected in the Mogi Guaçu River. The most abundant species of parasites were U. paradoxus and J. leporini, but they were not dominant. Within the localities, the hosts differed in parasite abundance, with the exception of Rio Pardo, where there was no significant difference among the species of fish collected (p> 0.05). The results also showed a significant difference (p <0.05) in the parasite abundance of the analyzed hosts in the different locations. The PERMDISP showed a significant difference (p <0.05) in the parasite dispersion between the localities, except between Rios Grande and Pardo. Leporinus obtusidens presented higher parasite diversity than L. friderici. No similarity decline was observed with the increase of the geographic distance, on the contrary, it was verified that the similarity increased with the distance. / FAPESP: 2012/24296-3
4

Modélisation mathématique des dynamiques hôtes-parasites ; de l’écologie parasitaire à l’écologie du génome / Mathematical modeling of host-parasite dynamics; from parasite ecology to genome ecology

Flores Ferrer, Alheli 14 June 2019 (has links)
Ce document est dédié à la modélisation dynamique des interactions hôtes-parasites. Il porte sur deux modèles biologiques très différents, mais étudiés à l’aide de modèles épidémiologiques standards construits à partir de systèmes dynamiques à compartiments. La première contribution est l’implémentation d’un modèle ‘micro-parasites’ pour étudier la transmission du parasite protozoaire Trypanosoma cruzi, agent étiologique de la trypanosomiase américaine (ou ‘maladie de Chagas’), au sein d’une communauté d’hôtes synanthropiques et domestiques. L’analyse du modèle mathématique montre pour la première fois dans ce système biologique un effet de dilution associé aux hôtes aviaires, ainsi que la possibilité de réduire la transmission à l’homme par modification de la composition de la communauté d’hôtes domestiques. La seconde contribution porte sur la dynamique des ‘parasites génomiques’ que sont les éléments transposables. En utilisant les analogies entre concepts de génomique et d’écologie proposées par l’approche d’ « Écologie du génome », il a été possible d’adapter des modèles développés pour les ‘macro-parasites’ à la dynamique d’éléments transposables de classe 1, les retro-transposons. L’analyse de cesmodèles permet de formuler des hypothèses sur l’importance relative de la démographie des hôtes, de la distribution du nombre de copies entre les individus et des mécanismes moléculaires de silencing de ces éléments, sur leurpersistance au sein de population d’hôtes se reproduisant de façon asexuée. / This document is dedicated to the dynamic modeling of host-parasite interactions. It is about two distant biological models, who are studied using standard epidemiological models built from dynamic compartmental models. The first contribution is the implementation of a 'micro-parasites' model to study the transmission of the protozoan parasite Trypanosoma cruzi, the etiological agent of American trypanosomiasis (or 'Chagas' disease), within a host community of synanthropic and domestic animals. The analysis of the mathematical model shows for the first time in this biological system a dilution effect associated with avian hosts, as well as the possibility of reducing the transmission to humans by modifying the composition of the domestic host communities. The second contribution deals with the dynamics of the "genomic parasites" that are the transposable elements. Using the analogies between genomics and ecology concepts proposed by the "Genome Ecology" approach, it was possible to adapt models developed for 'macro-parasites' to the dynamics of transposable elements of class 1, retro-transposons. The analysis of these models makes it possible toformulate hypotheses on the relative importance of the host demography, the distribution of the number of copies between individuals and the molecular mechanisms of silencing of these elements, on their persistence within the population of hosts reproducing asexually.
5

Biodiversidade das Comunidades Parasit?rias dos peixes do Rio Guandu, Estado do Rio de Janeiro, Brasil

Azevedo, Rodney Kozlowiski de 26 February 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-08T11:37:07Z No. of bitstreams: 1 2010 - Rodney kozlowiski de Azevedo.pdf: 3579688 bytes, checksum: 3baae7dd721eab10e68db71bdf0e32da (MD5) / Made available in DSpace on 2016-08-08T11:37:07Z (GMT). No. of bitstreams: 1 2010 - Rodney kozlowiski de Azevedo.pdf: 3579688 bytes, checksum: 3baae7dd721eab10e68db71bdf0e32da (MD5) Previous issue date: 2010-02-26 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ, FAPERJ. / The Guandu River is the most important source of water supply for the municipality of Rio de Janeiro and Baixada Fluminense. It is characterized as the river system that has the greatest diversity of fish and the largest biomass of the Basin of the Sepetiba Bay. From April 2003 to September 2009 786 fish specimens, belonging to 21 species from the Guandu River, near the dam of water treatment station (WTS) (22? 48' 32"S, 43? 37'35"W), State of Rio de Janeiro, were collected and analyzed to study the biodiversity of their metazoan parasites, considering the strategic importance of this river in the State of Rio de Janeiro. Seventy percent of the fish were parasitized by at least one metazoan parasite. Of the parasites found 55% were endoparasites and 45% were ectoparasites. A total of 81 parasite species were found, belonging to nine groups: Acanthocephala, Cestoda, Crustacea, Digenea, Hirudinea, Mollusca, Monogenea, Myxozoa and Nematoda. The monogeneans had higher species richness and the metacercariae and nematode larvae had the lowest host specificity. The results of this study indicate that the parasite communities of fishes from Guandu River were characterized by low richness and evenness, isolationist communities and higher values of taxonomic diversity in species of omnivorous fish and in species that forming schools. In this study were made 38 new host records and 25 new locality records, demonstrating the biological diversity of Guandu River. / O Rio Guandu ? a mais importante fonte de abastecimento de ?gua para o munic?pio do Rio de Janeiro e parte da Baixada Fluminense. Caracteriza-se como o sistema fluvial que det?m a maior diversidade de peixes e a maior biomassa da bacia hidrogr?fica da Ba?a de Sepetiba. Entre o per?odo de abril de 2003 a setembro de 2009 foram coletados e analisados 786 esp?cimes de peixes, pertencentes a 21 esp?cies, provenientes do rio Guandu, pr?ximo ? barragem da Esta??o de tratamento de ?gua (ETA) (22?48?32?S, 43?37?35?W), Estado do Rio de Janeiro, com o objetivo de estudar a biodiversidade dos seus metazo?rios parasitos. Setenta por cento dos peixes estava infectado/infestado por pelo menos uma esp?cie de metazo?rio parasito. Do total de parasitos encontrados 55% foram endoparasitos e 45% foram ectoparasitos. Um total de 81 esp?cies de parasitos foi encontrado, pertencentes a nove grupos: Acanthocephala, Cestoda, Crustacea, Digenea, Hirudinea, Mollusca, Monogenea, Myxozoa e Nematoda. Os monogen?ticos apresentaram maior riqueza de esp?cies e as metacerc?rias e as larvas de nemat?ides apresentaram a mais baixa especificidade parasit?ria. Os resultados obtidos no presente trabalho indicam que as comunidades parasit?rias dos peixes do rio Guandu foram caracterizadas pela baixa riqueza e equitabilidade, por comunidades isolacionistas e pelos maiores valores de diversidade taxon?mica nas esp?cies de peixes on?voros e que formam cardumes. No presente estudo foram feitos 38 novos registros de hospedeiro e 25 novos registros de localidade, o que demonstrou a diversidade biol?gica do rio Guandu

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