Dissertations / Theses: 'Trematoda'

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Wolber, Jens-Erik. "Möglichkeiten der alternativen arzneimittelfreien Bekämpfung des fischpathogenen Trematoden Bucephalus polymorphus Baer, 1827 (Trematoda: Bucephalidae)." [S.l. : s.n.], 2004. http://www.diss.fu-berlin.de/2004/215/index.html.

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Pinto, Hudson Alves. "Infecção natural de Melanoides tuberculata (Mollusca: Thiaridae) por Centrocestus formosanus (trematoda: Heterophyidae) e por Philophthalmus gralli (Trematoda: Philophthalmidae) no Brasil." Universidade Federal de Minas Gerais, 2009. http://hdl.handle.net/1843/SAGF-8H9QEZ.

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Visando avaliar aspectos biológicos e taxonômicos de trematódeos transmitidos por Melanoides tuberculata (Müller, 1774) no Brasil, coletas malacológicas foram realizadas na represa da Pampulha, Belo Horizonte, Minas Gerais, no período entre março de 2006 a julho de 2009. De 38344 exemplares de M. tuberculata coletados e examinados, 279215 (7,36%) apresentaram-se infectados por larvas de trematódeos que, após caracterização morfológica preliminar, foram utilizadas para estudos biológicos experimentais. Estágios evolutivos obtidos (cercárias, metacercárias, rédias, parasitos adultos, ovos e/ou miracídios) foram estudados in vivoa fresco e após processo de fixação, coloração e montagem de lâminas permanentes, seguida de análise morfológica e morfométrica em microscópio de luz. Cercárias do tipo Pleurolofocerca foram encontradas em 206 268 (7,03%) exemplares de M. tuberculata e utilizadas para a infecção de Poecilia reticulata Peters, 1859. Metacercárias obtidas nas brânquias dos peixes 30 dias após a infecção foram inoculadas por via oral a Mus musculus (Linnaeus, 1758) da linhagem AKR/J e parasitos adultos recuperados no intestino delgado dos camundongos 30 dias após infecção DPI foram identificados como Centrocestus formosanus (Nishigori, 1924). Outro tipo cercariano, do grupo Megalura, foi encontrado em 11 (0,33%) exemplares de M. tuberculata coletadoslarvas do . Estas larvas formaram metacercárias em substrato sólido que foram utilizadas para a infecção de Gallus gallus domesticus (Linnaeus, 1758) jovens. Parasitos adultos obtidos da membrana nictitante e saco conjuntival das aves, 30 dias após infecção, foram identificados como Philophthalmus gralli Mathis & Leger, 1910. Este é o primeiro registro de ambas as espécies de trematódeos em M. tuberculata no Brasil.

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Tomba, Abbie Marie Feminella Jack W. "Effects of trematode parasites on habitat use and disturbance response of freshwater snails in the genus Elimia." Auburn, Ala., 2006. http://repo.lib.auburn.edu/Send%2012-15-07/TOMBA_ABBIE_52.pdf.

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João, Roberto Carlos Ferreira. "Schistosoma mansoni (Trematoda: Digenea) Sambom, 1907: diagnóstico ultraestrutural e laboratorial." reponame:Repositório Institucional da FIOCRUZ, 2011. https://www.arca.fiocruz.br/handle/icict/6315.

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A esquistossomose é uma das parasitoses mais prevalentes no mundo e o Schistosoma mansoni Sambon, 1907 é o trematódeo agente da esquistossomose intestinal, endêmica em países da América do Sul, África, Oriente Médio e Caribe. Em Angola, os primeiros dados da esquistossomose foram registrados em 1897 na província do Bengo, mas a prevalência do S. mansoni é, no entanto pouco notificada. No âmbito da cooperação internacional Fiocruz (Brasil)-Fesa (Angola) que visa capacitar no Brasil profissionais da área de Saúde de Angola, este trabalho está voltado para estudos sobre a caracterização ultraestrutural e diagnóstico laboratorial do S. mansoni. Os objetivos incluíram: estudar a topografia de adultos de S. mansoni; caracterizar os tubérculos do tegumento do macho por microscopia eletrônica de varredura, de transmissão e por microscopia a laser confocal; descrever um método alternativo para exame de fezes, baseado no princípio de Kato-Katz, utilizando o fixador SAF e comparar o método Kato-Katz utilizado para o diagnóstico da esquistossomose com o método alternativo. A topografia dos machos evidenciou a presença de tubérculos na superfície dorsal do corpo que em cortes ultrafinos aparecem como evaginações tegumentares que abrem espaço entre as fibras musculares elevando as membranas basal e apical. Entre estas membranas que revestem os tubérculos, há vesículas eletrondensas, eletronlúcidas e corpos alongados. As vesículas formadas na região interna do tegumento, próximo ao núcleo das células são encontradas nos canais citoplasmáticos que chegam à superfície externa do sincício. Os espinhos dos tubérculos aparecem sobre a membrana basal, próximos às vesículas eletrondensas. No tegumento há organelas sensoriais contendo bulbo basal e projeção apical com cílio e corpos basais. O canal ginecóforo apresenta espinhos pequenos, uniformes e organelas sensoriais uniciliadas. A camada entre a membrana basal e a apical é mais homogênea e os espinhos aparecem de forma uniforme no tegumento sem a formação de tubérculos. Utilizando o diagnóstico laboratorial pelo Kato-Katz não foi possível visualizar os ovos no momento da montagem da lâmina (0h), mas a incidência de visualização aumentou em 24h. Na técnica modificada do SAF, os ovos foram identificados imediatamente e a visualização diminuiu ao longo do tempo. Comparando em função do tempo, as médias da análise de ovos por grama de fezes (OPG) das três infecções nas duas técnicas, observou-se que o número de ovos encontrados com a técnica de SAF (0h) foi maior em 7,7% do que com Kato-Katz (24 h). Não houve diferença significativa entre os resultados obtidos com SAF (0h) e Kato-Katz (24 h). O mesmo resultado foi verificado com 12 horas para as duas técnicas. No segundo experimento o OPG pelo SAF (1h) foi 13,1% maior do que Kato-Katz (24h) de leitura. Comparando os resultados obtidos nas duas técnicas com 24 h de leitura, o OPG foi 32,5% maior na técnica de Kato-Katz do que SAF. O método experimental baseado no fixador SAF é eficiente para diagnóstico laboratorial alternativo, simples, rápido, de baixo custo e eficiente para o diagnóstico de esquistossomose mansônica. Este estudo trará novos avanços no diagnóstico desta doença em Angola.
Schistosomiasis is one of the most prevalent parasitic diseases in the world and the trematode Schistosoma mansoni Sambon, 1907 is the agent of intestinal schistosomiasis, endemic in countries of South America, Africa, Middle East and the Caribbean. In Angola, the infection was first recorded in 1897 in the Bengo province, however the prevalence of S. mansoni remains underestimated. In the framework of an international cooperation between Fiocruz (Brazil)-Fesa (Angola), which aims to train health professionals from Angola in Brazil, this work is focused on ultrastructural studies and laboratory diagnosis of S. mansoni. The objectives included: to study the topography of adult S. mansoni; to characterize the tubercles of the tegument of the male by scanning and transmission electron microscopy and laser confocal microscopy; to describe an alternative method for stool examination, based on the principle of Kato-Katz method, using the SAF fixative, and compare the Kato- Katz method used for the diagnosis of schistosomiasis with the alternative method. The topography of the males showed the presence of tubercles on the dorsal surface of the body that in ultrathin cuts appear like tegumentary evaginations that interweave between the muscle fibers raising the basal and apical membranes. Between these membranes that cover the tubercles, there are electrondense and electronlucid vesicles, and elongated bodies. The vesicles formed in the inner region of the integument near the cell nucleus are found inside the cytoplasmic channels reaching the outer surface of the syncytium. The spines of the tubercles emerge over the basal membrane, near the electrondense vesicles. The integument has sensory organelles containing a basal bulb and apical projection with cilium and basal bodies. The ginecoforous channel presents uniform small spines, and uniciliate sensory organelles. The layer between the basal and apical membrane is more homogeneous with spines appearing evenly, without forming tubercles. The laboratory diagnosis using the Kato-Katz method was not successful to show the eggs at time (0h), but the display increased at 24h after the sampling. The modified technique of the SAF, showed the eggs immediately and display decreased over time. Comparing both methods by time, the mean number of eggs per gram of feces (EPG) by two techniques of the three infections, we found that the number of eggs found with the technique of SAF (0h) was higher by 7.7% than with Kato-Katz (24 h). There was no significant difference between the results obtained with SAF (0h) and Kato-Katz (24 h). The same result was observed for 12 hours with both techniques. In the second experiment, the EPG by SAF (1h) was 13.1% higher than Kato-Katz (24h). Comparing the results of the two techniques with 24 hours of sampling, the EPG was 32.5% higher in the Kato-Katz technique than SAF. The experimental method based on the SAF fixative is an efficient alternative for laboratory diagnosis, being simple, fast, inexpensive and efficient for the diagnosis of schistosomiasis. This study will bring new advances in the diagnosis of this disease in Angola.

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Bernardon, Fabiana Fedatto. "Helmintos de aves aquáticas (Pelecaniformes: Ardeidae) do sul do Brasil." Universidade Federal de Pelotas, 2013. http://repositorio.ufpel.edu.br/handle/ri/2321.

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The Ardeidae family is composed of more than 60 species, being one of the largest and most representative families of birds with characteristics adapted to wetlands. Rio Grande do Sul is characterized by presenting ecosystems which harbor a unique diversity of waders, where there is the record of 13 species of Ardeidae. Due to lack of information on the diversity of helminths in the Ardeidae family in Rio Grande do Sul, the work was developed with the goal of identifying the helminthfauna of nine species of Ardeidae and determine the parameters of prevalence, mean abundance and mean intensity. Were examined 30 birds of the Ardeidae family (Pelecaniformes), Ardea alba , Ardea cocoi, Butorides striata, Bubulcus ibis, Egretta thula, Ixobrychus involucris, Nycticorax nycticorax , Syrigma sibilatrix e Tigrisoma lineatum from the natural environment of the cities of Pelotas, Capão do Leão e Rio Grande, RS, Brazil. The birds were necropsied to collect helminths, prepared in accordance with the protocols used for each group and identified. As a result there was obtained species of Trematoda, Nematoda and Acanthocephala and their parasitological parameters as follow below: Trematoda: Digenea, Amphimerus interruptus (P=3,3%; AM=0,1; IM= 3,0), Apharyngostrigea ardearum (P=40%; AM=18,6; IM= 46,6), Ascocotyle sp. (P=33,3%; AM=88,4; IM= 265,3), Clinostomum complanatum (P=30%; AM=1,1; IM= 3,8), Episthmium proximum (P=23,3%; AM=1,0; IM=4,2), Ithyclinostomum dimorphum (P=6,6%; AM=0,1; IM=2,5), Nephrostomum limai (P=10%; AM= 0,3; IM=3,6), Ribeiroia insignis (P=10%; AM=2,8; IM=28,0 ) and Stomylotrema sp. (P=3,3%; AM=0,03; IM=1,0) belonging to eight families: Nematoda: Contracaecum microcephalum (P=80%; AM=15,1; IM=18,8), Desportesius invaginatus (P=43,3%; AM=2,76; IM=6,3), Desmidocercella ardeae (P=16,6%; AM=1,3; IM=8,0), Eustrongylides sp. (P=13,3%; AM=1,3; IM=10,2) and Baruscapillaria sp. (P=10%; AM=0,5; IM=5,0). Acanthocephala: Acanthocephalus sp. (Echinorhynchidae) (P=3,33%; AM=0,03; IM=1,0), Andracantha sp. (P=33,3%; AM=15,2; IM=45,8), Arhythmorhynchus sp. (P=6,66%; AM=0,16; IM=2,5) and Polymorphus sp. (Plagiorhynchidae) (P=13,3%; AM=1,3; IM=10,2). Tigrisoma lineatum was the only negative for all groups Ixobrychus involucris was negative for the presence of Trematoda and Bubulcus ibis negative for acanthocephalans. The Trematoda, Nematoda and Acanthocephala mentioned above are for the first time recorded in the Ardeidae family in Rio Grande do Sul in Brazil, some of the hosts and their helminth characterizes first occurrence. We have found insulated proglottids of cestodes in small and large intestine in some birds, but could not identify them.
A família Ardeidae é composta por mais de 60 espécies sendo uma das maiores e mais representativas famílias de aves com características adaptadas às áreas úmidas. O Rio Grande do Sul caracteriza-se por apresentar ecossistemas que abrigam uma diversidade ímpar de aves pernaltas onde há o registro de 13 espécies de ardeídeos. Devido a escassez de informações sobre a diversidade de helmintos em Ardeidae no Rio Grande do Sul, desenvolveu-se o trabalho com o objetivo de identificar a helmintofauna de nove espécies de ardeídeos e determinar a os parâmetros de prevalência, abundância e intensidade médias. Foram examinados 30 aves. Ardea alba, Ardea cocoi, Butorides striata, Bubulcus ibis, Egretta thula, Ixobrychus involucris, Nycticorax nycticorax, Syrigma sibilatrix e Tigrisoma lineatum, provenientes de ambiente natural dos municípios de Pelotas, Capão do Leão e Rio Grande RS, Brasil. As aves foram necropsiadas para a coleta dos helmintos, preparadas de acordo com os protocolos utilizados para cada grupo e identificadas. Como resultado obteve-se espécies de trematódeos, nematóides e acantocéfalos e seus parâmetros parasitológicos como seguem a seguir: Trematoda: Digenea, Amphimerus interruptus (P=3,3%; AM=0,1 ;IM=3,0), Apharyngostrigea ardearum (P=40%; AM=18,6; IM= 46,6), Ascocotyle sp. (P=33,3%; AM=88,4; IM= 265,3), Clinostomum complanatum (P=30%; AM=1,1; IM=3,8), Episthmium proximum (P=23,3%; AM=1,0; IM=4,2), Ithyclinostomum dimorphum (P=6,6%; AM=0,1; IM=2,5), Nephrostomum limai (P=10%; AM= 0,3; IM=3,6), Ribeiroia insignis (P=10%; AM=2,8; IM=28,0) e Stomylotrema sp. (P=3,3%; AM=0,03; IM=1,0) pertencentes a oito famílias; Nematoda: Contracaecum microcephalum (P=80%; AM=15,1;IM=18,8),Desportesius invaginatus(P=43,3%; AM=2,76; IM=6,3), Desmidocercella ardeae (P=16,6%; AM=1,3; IM=8,0), Eustrongylides sp. (P=13,3%; AM=1,3; IM=10,2) e Baruscapillaria sp. (P=10%; AM=0,5; IM=5,0). Acanthocephala: Acanthocephalus sp. (Echinorhynchidae) (P=3,33%; AM=0,03; IM=1,0), Andracantha sp. (P=33,3%; AM=15,2; IM=45,8), Arhythmorhynchus sp. (P=6,66%; AM=0,16; IM=2,5) e Polymorphus sp. (Plagiorhynchidae) (P=13,3%; AM=1,3; IM=10,2). Tigrisoma lineatum foi o único ardeídeo negativo para todos os grupos, enquanto que Ixobrychus involucris quanto à presença de trematódeos e Bubulcus ibis quanto à presença de acantocéfalos. Os trematódeos, nematóides e acantocéfalos citados anteriormente são pela primeira vez registrados em ardeídos no Rio Grande do Sul. No Brasil, alguns dos hospedeiros e respectivos helmintos constituem primeira ocorrência. Foram encontradas proglotes isoladas de cestóides no intestino delgado e grosso em algumas aves, porém não foi possível identificá-las.

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Zellmer, Patricia J. "The identification and characterization of Caecidotea racovitzai (Isopoda) as the ecologically important second intermediate host of the invasive trematode Leyogonimus polyoon (Trematoda), and aspects of the natural history of each on Shawano Lake, Wisconsin /." Link to full text, 2009. http://epapers.uwsp.edu/thesis/2009/Zellmer.pdf.

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Thesis (M.S.)--University of Wisconsin--Stevens Point, 2009.
Submitted in partial fulfillment of the requirements of the degree Master of Science in Natural Resources (Wildlife), College of Natural Resources. Includes bibliographical references (leaves 167-174).

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Carter, Phoebe Kate Louise. "The impact of low concentrations of cadmium on host-monogenean interactions." Thesis, University of Stirling, 2003. http://hdl.handle.net/1893/2593.

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Interpreting data gathered from field studies that investigate the effect of pollution on fish parasites is complicated by the presence of multiple parasite species and mixed pollutant loads. The aim of this study was, therefore, to use controlled experimental studies to assess the impact of a single heavy metal, cadmium, on selected species of the monogenean genera, Dactylogyrus Diesing, 1850 and Gyrodactylus von Nordmann, 1832 and on their hosts, Cyprinus carpio L. and Poecilia reticulata (Peters). The first host-monogenean system investigated was the gill fluke Dactylogyrus extensus Mueller & Van Cleave, 1932 and its host C. carpio; the second system, Gyrodactylus - P. reticulata, involved individual investigations on Gyrodactylus turnbulli Harris, 1986 and G. bullatarudis Turnbull, 1956. Independent investigations of parasite biology and host responses were undertaken in order to elucidate host-parasite interactions in the presence of cadmium. The maximum permitted level of cadmium in controlled freshwater sources is set at 5μg/l by EEC Directive 76/464/EEC and experiments were carried out using this concentration and the higher, but environmentally realistic, levels of 20-50μg/l. For the first time it has been demonstrated that Dactylogyrus extensus exposed to 5μg/l cadmium show a subtle enhancement in the in vitro rate of oviposition and a statistically significant enhancement in their in vivo rate of oviposition after 9-10 days exposure. The effect of cadmium on egg production by D. extensus and on selected aspects of the innate immune response of C. carpio were investigated in separate experiments. Although run independently of each other, the sample times of both experiments were the same. It was found that the treatment in which the rate of oviposition by the parasite was greatest, was the treatment, where at the same sample point, the phagocytic activity of C. carpio was greatest. Exposure of D. extensus to the higher level of 30μg/l cadmium, also enhanced egg production after 9 days, but, 14-30 days exposure resulted in a lower rate of oviposition than that recorded in control parasites, suggesting that cadmium may directly, as well as indirectly, influence the reproductive biology of this parasite species. The hatching of D. extensus eggs was similarly affected by cadmium exposure, with those produced and incubated in 5μg/l cadmium demonstrating a statistically significant more rapid hatch rate than the controls, while those produced and incubated at the higher concentration (30μg/l) showed a statistically significant slower rate of hatch than the controls. Exposure of adult D. extensus to cadmium concentrations ranging from 5 to 3,400μg/l in vitro resulted in an enhancement of survival above the controls. Only at 13,100μg/l cadmium was there a statistically significant reduction in survival and in vitro egg production. Atomic adsorption spectrometry demonstrated that D. extensus is a net accumulator of cadmium, with the concentration of cadmium accumulated by the parasite, increasing with increasing exposure concentrations. The degree of cadmium accumulation in C. carpio organs was in the order of gills > kidney > liver > muscle=spleen. Even at 5μg/l, the level of cadmium detected in the muscle (ca. 0.2μg/g) exceeded the permitted level in food fish (0.05 mg/kg (μg/g), after only 9 days exposure. The haematological and immunological responses of C. carpio exposed to 5μg/l cadmium showed only subtle differences from the control fish, with these differences being most marked in the early stages of the trial (days 9-14). By the end of the trial there was little difference in the responses of these fish from the controls, suggesting that carp can adapt to low-level cadmium exposure. Cadmium at 50μg/l resulted in exaggerated alterations to the immune responses of carp, with statistically higher cortisol levels, phagocytic activity of kidney phagocytes, granulocyte number and significant lymphopenia, at days 6 to 14 of the trial. Several of these changes are indicative of a typical stress response. The respiratory burst and phagocytosis of kidney phagocytes in C. carpio appear to be linked to the level of cortisol, with both factors increasing as cortisol levels fall, suggesting that the effects of cadmium on the immune system may be mediated to some extent via the production of corticosteroids. Cadmium at concentrations below the permitted maximum caused statistically significant increases in the population size of both Gyrodactylus bullatarudis Turnbull, 1956 and G. turnbulli Harris, 1986 on P. reticulata. Statistically significant differences in the population size of G. turnbulli were also recorded between male and female P. reticulata. Exposing P. reticulata to 5μg/l cadmium resulted in little difference in the respiratory burst of kidney phagocytes and the production of myeloperoxidase when compared to the same parameters in control fish. The phagocytic activity of these fish was, however, consistently elevated above the controls. Exposure to 20μg/l cadmium resulted in a further enhancement of both phagocytosis and respiratory burst in P. reticulata. Unlike, C. carpio, no adaptation to cadmium exposure was observed in P. reticulata within a 30-day period. During the trial, subtle differences in the innate immune parameters of male and female guppies also emerged. None of the three innate immune parameters investigated, i. e. phagocytic activity, respiratory burst and myeloperoxidase production, appeared to correlate to the observed differences in the population growth of G. turnbulli. The finding that cadmium at levels below its permitted maximum can significantly increase numbers of Gyrodactylus spp. to the detriment of P. reticulata, suggests that the water quality guidelines, with regard to the permitted concentration of this metal, should be reviewed. This study has provided the first information on the effects of low concentrations of cadmium on selected monogenean parasites and their hosts and has been the first to attempt to elucidate host-parasite interactions in the presence of this metal. The study has provided a range of interesting findings and has offered several avenues for further investigations into a complex field of research that is still in its infancy.

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NOVAES, M. T. "Caracterização química e atividade anti-helmíntica in vitro do citral e dos óleos essenciais de Cymbopogon citratus e Cymbopogon wynterianus sobre adultos de Fasciola hepatica." Universidade Federal do Espírito Santo, 2017. http://repositorio.ufes.br/handle/10/7798.

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O parasito Fasciola hepatica é um trematódeo que acomete o fígado de bovinos, ovinos, animais silvestres e humanos. É responsável por grandes perdas econômicas em diversos países. A resistência em F. hepatica, principalmente ao triclabendazol, tem estimulado a busca de produtos alternativos para a fasciolose. Diante disto, objetivou-se com este estudo avaliar a atividade do óleo essencial (OE) de Cymbopogon citratus (capimlimão) e de seus componentes majoritários citral (neral + geranial) bem como do OE de Cymbopogon wynterianus (citronela) nas concentrações 0,025%, 0,05% e 0,1% (m v-1) sobre parasitos adultos de F. hepatica. Os OEs foram extraídos utilizando um aparelho do tipo Clevenger e o citral foi obtido comercialmente e estes foram caracterizados por cromatografia gasosa (CGDIC e CG-EM). Foram utilizados oito adultos de F. hepatica para cada grupo em placas de Petri individuais e estas foram analisadas após três, doze e quinze horas, sendo utilizado um exemplar de F. hepatica de cada grupo para a análise histológica. Para a análise dos dados, foi utilizado a tabela de contingência para o teste do qui-quadrado. Após 15h de análise, observou-se que o OE de C. citratus e o citral inibiram a motilidade da F. hepatica em todas as concentrações testadas e o OE de C. wynterianus apenas nas concentrações de 0,05 e 0,1% (m v-1 ). Nos OEs e no citral houve a perda de espinhos e de uma das camadas do tegumento, com exceção do citral na concentração de 0,025% (m v-1) onde os espinhos e os tegumentos continuaram presentes.

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Silva, Gilcia Aparecida de Carvalho. "Estudos sobre xifidiocercarias (Trematoda) e seu parasitismo em larvas de mosquitos (Diptera : Culcidae)." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314448.

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Orientadores: Carlos Fernando Salgueirosa de Andrade, Marlene Tiduko Ueta
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O presente trabalho teve por objetivo avaliar a ocorrência de xifidiocercárias na região de Campinas e em duas localidades no Vale do Ribeira, Estado de São Paulo e estudar o parasitismo das mesmas sobre larvas de mosquitos da família Culicidae em condições experimentais. Realizaram-se coletas de moluscos em corpos de água doce na região de Campinas e nos municípios de Registro e Miracatu no Vale do Ribeira, Estado de São Paulo, no período de setembro de 1996 a fevereiro de 1999. Foram coletadas as espécies Lymnaea columella, Physa marmorata, Biomphalaria tenagophila, Drepanotrema cimex e D. lucidum. Também foram coletados exemplares de Biomphalaria e Drepanotrema os quais não foram dissecados para a confirmação da espécie, podendo pertencer à uma das espécies acima identificadas. Após a exposição dos moluscos à luz incandescente de 60 W encontrou-se exemplares de limneídeos provenientes de Miracatu, SP, apresentando uma variação de 0,2 a 1,0% de parasitismo por cercárias de Fascio/a hepatica, 0,4 a 8,3% de parasitismo por xifidiocercárias (Haematoloechidae) e 3,3% de parasitismo por cercárias de equinostomatídeo, além de moluscos planorbídeos parasitados por furcocercárias (prevalência de 1,5%), cercárias de equinostomatídeo com 14,1% de prevalência e 1,5 a 15,6% de parasitismo por xifidiocercárias. As xifidiocercárias encontradas em planorbídeos eram diferentes das obtidas de limneídeos. Em Louveira, SP, foi encontrado um exemplar de Biomphalaria sp. parasitado por furcocercárias (1,9%). Na localidade ROSA em Campinas, SP encontrou-se um exemplar de Biomphalaria sp. e um de L. columella parasitados por furcocercárias (7,6%) e cercárias de equinostomatídeo (1,5%), respectivamente. Na lagoa da UNlCAMP, atrás da Faculdade de Educação Física (UNI-I), também em Campinas, encontrou-se um exemplar de L. columella parasitado por furcocercárias (2,3%). Três exemplares de B. tenagophila provenientes de Miracatu, estavam duplamente infectados por furcocercárias, tanto com ocelo como sem esta estrutura totalizando 3,8% de parasitismo por estas cercárias, além de seis moluscos da mesma espécie (4,3%) com infecção dupla por xifidiocercárias e cercárias de equinostomatídeo. Dois exemplares de L. columella da mesma localidade, também apresentaram infecção dupla por xifidiocercárias e cercárias de F. hepatica (4,4%) e um exemplar com xifidiocercárias e equinostomatídeo (1,7%). Houve também infecção dupla por xifidiocercárias e rédias em quatro moluscos, que apresentou parasitismo variando de 1,2 a 3,2%. Estudou-se a morfologia das xifidiocercárias eliminadas por L. columella e comparou se com descrições de outros autores. Com estes estudos, concluiu-se que as mesmas pertenciam a subordem Plagiorchiata, fanúlia Haematoloechidae, mais provavelmente gênero Haematoloechus. Tais cercárias, quando colocadas em contato com larvas de mosquitos das espécies Culex quinquefasciatus, Aedes albopictus ou Ae. aegypti, penetraram e encistaram nas larvas, formando as metacercárias. Observou-se em geral atraso no desenvolvimento das larvas de culicídeos parasitadas, que na maioria das vezes evoluíram até a morte. A infecção nas larvas foi sempre de 100% e a mortalidade máxima nos experimentos foi de 72,2% para larvas de Cx. quinquefasciatus, 100% para Ae. albopictus e 95% para Ae. aegypti. Verificou-se ainda, que quando não ocorreu a morte das larvas infectadas pelas xifidiocercárias, destas emergiam adultos infectados com metacercárias vivas e bem ativas. Também foi feita uma simples infecção experimental em rãs da espécie Rana catesbeiana, considerando-se anfibios como possíveis hospedeiros definitivos. Larvas de mosquito parasitadas por xifidiocercárias foram oralmente administradas às rãs, mas não foi possível recuperar nenhum trematódeo nos órgãos dos anfibios
Abstract: The present work airned to evaluate the xiphidiocercariae occurrence in Campinas region and two places in Vale do Ribeira, São Paulo State, and to study the xiphidiocercariae parasitism in mosquitoes larvae (Culicidae) under experimental conditions. Snails were collected ITom ITesh water collections in the region of Campinas, Registro and Miracatu in the Vale do Ribeira, São Paulo State, in the period ITom September-1996 to February-1999. The species collected were Lymnaea columella, Physa marmorata, Biomphalaria tenagophila, Biomphalaria sp., Drepanotrema cimex, D. lucidum and Drepanotrema sp. After exposing the snails to incandescent light (60 W), lymnaeid snails ITom Miracatu, SP, infected by Fasciola hepatica were found presenting of 0,2 to 1,0% of parasitism, besides 0,4 to 8,3% of parasitism with xiphidiocercariae (Haematoloechidae) and 3,3% of parasitism with echinostomatid cercariae. For the same locality planorbid snails were found parasited with furcocercariae (1,5% of prevalence), with echinostomatid cercariae (14,1% of prevalence) and xiphidiocercariae ITom 1,5 to 15,6% of parasitism. The xiphidiocercariae found in planorbid were different ITom that obtained ITom lymnaeid. In Louveira, SP it was found one Biomphalaria sp. snail infected with furcocercariae (1,9%). In the ROSA place (Campinas), SP it was found an individual of Biomphalaria sp. and one of L. columella infected by furcocercariae (7,6%) and echinostomatid cercariae (1,5%), respectively. In the place UNI-I, also in Campinas, one L. columella was infected by furcocercariae (2,3%). Three individuaIs of B. tenagophila from Miracatu were double infected by two types of furcocercariae, (with or without ocellus), totaling 3,8% of parasitism for these cercariae, besides six snails of the same species (4,3%) with double infection for xiphidiocercariae and echinostomatid cercariae. Two L. columella from the same place, also presented double infectionfor xiphidiocercariae and F. hepatica (4,4%) and an exemplary with xiphidiocercariae and echinostomatid cercariae (1,7%). There was also double infection for xiphidiocercariae and rediae in four snails that presented a parasitism varying of 1,2 to 3,2%. The morphology of the xiphidiocercariae eliminated by L. columella was studied and comparison with other authors descriptions. From these studies, it was possible to conc1ude the cercariae belonging to the suborder Plagiorchiata, family Haematoloechidae, and probably genus Haematoloechus. When in contact with mosquitoes larvae of the species Culex quinquefasciatus, Aedes albopictus or Ae. aegypti, such cercariae penetrated and encysted in the larvae forming metacercàriae. It was observed in general a developmental of delay the culicid larvae caused by the parasitism that most of the time developed to the death. The infection in the larvae was always accomplished (100%) and the maximum mortality in the experiments was of 72,2% to Cx. quinquefasciatus larvae, 100% for Ae. albopictus and 95% for Ae. aegypti. It was still veritied that when the death do not occured to the xiphidiocercariae infected larvae, the resulting adults were infected with ative and very active metacercariae. It was also made a simple experimental infection in frogs of the specie Rana catesbeiana, considering amphibians as possible definitive host. Mosquito larvae parasited by xiphidiocercariae where orally administred to the frogs but it was not possible to recover any trematode in the amphibians organs
Mestrado
Mestre em Parasitologia

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Nolan, Matthew John. "Sanguinicolidae von Graff, 1907 (Platyhelminthes : Digenea) of Indo-West Pacific fishes /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19026.pdf.

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Williams, Emily Rose-Margaret. "Parasites and the ecological undead: marine snails and their suite of trematodes." Thesis, The University of Sydney, 2012. https://hdl.handle.net/2123/28920.

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The invisible interactions between parasites and their hosts are important elements of the ecology and biology of host populations. Parasites can shape the morphology, distribution, physiology and behaviour of individual hosts - some commonly studied host-parasite interactions often involve gastropods and trematodes. Trematodes can have detrimental effects on their snail hosts, yet many such relationships are relatively unknown. One such relationship is that of the mud whelks, Velacumantus australis, many of which are infected by several species of parasitic trematode. Australian estuaries and lagoons are commonly populated with these snails. Little work has been done, however, on how these snails are affected by their trematodes. My overall aim was to create a more comprehensive picture of the relationship between trematodes and their snail hosts, since it is unknown what is occurring within populations of these snails in Australia. Through dissections and experiments, I described all the species infecting the snails, including those previously unknown to science; quantified infection prevalence within different populations of snails in New South Wales; compared infection with host size, both in situ and through growth of host bodies over time; assayed proteins and lipids from host tissues to quantify energy reserves; and finally, tested whether snails displayed different behaviours depending on infection status. My results show that parasitism varies temporally and on small and large spatial scales, most likely because of recruitment and presence of other hosts. The effects of parasitism on the host body include differences in growth and energy reserves, and appear to be influenced depending on the species of trematode. The activity and locomotory behaviour of snails is also affected by trematode infection, whether the snail has a neighbour, and the infection status of the neighbouring snail. These results show that the relationship between V australis and its trematodes is more complex than predicted and is influenced by dynamic interactions between spatial variability and parasitism. Future experiments with these snails and other snail-trematode relationships in similar systems should include different spatial scales as well as different species of trematodes in order to disentangle the relationships between parasitism and environmental variation.

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GOMES, M. C. "Helmintos gastrointestinais de tartarugas verdes (chelonia mydas) recolhidos no litoral do Estado do Espírito Santo: Estudo ecológico e caracterização morfológica de ovos." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/7804.

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Federal do Espírito Santo, Alegre, ES, 2016. Todas as espécies de tartarugas marinhas existentes estão ameaçadas de extinção em algum grau, sendo Chelonia mydas a que possui hábitos mais costeiros e está amplamente distribuída pela costa brasileira. São diversas as ameaças, principalmente ligadas à ação antrópica, e dentre as enfermidades, o parasitismo é tido como provável causa de debilidade e morte. Objetivou-se avaliar a comunidade de helmintos gastrointestinais e realizar a caracterização morfológica de seus ovos em tartarugas-verdes recolhidas no litoral do Espírito Santo no período de março a agosto de 2015. Foram utilizadas 36 tartarugas marinhas juvenis da espécie C. mydas, sendo o trato gastrointestinal inteiro separado e dividido em três porções: esôfago/estômago, intestino delgado e intestino grosso. Cada porção foi aberta e inspecionada à procura de parasitos e os exemplares encontrados foram separados macroscopicamente para posterior montagem permanente. Para cada espécie encontrada foram determinadas a prevalência, intensidade média e abundância média de espécies. Para a avaliação coproparasitológica, as fezes foram processadas com técnica de sedimentação e os ovos encontrados foram caracterizados morfologicamente e comparados aos encontrados nos helmintos adultos. Das 36 tartarugas avaliadas, a prevalência de helmintos foi de 94,44% (34/36), com um total de 10.734 helmintos recuperados. Foram encontradas 18 espécies de trematódeos pertencentes a quatro famílias. A riqueza média de espécies foi de 4,29 ± 2,19. Os parasitos mais prevalentes foram Cricocephalus albus, Metacetabulum invaginatum e Neoctangium travassosi, ambos com 61,11% (22/36), seguidos de Pronocephalus obliquus com 33,33% (12/36), e Glyphicephalus lobatus com 30,55% (11/36). Foram encontrados e identificados quatro diferentes morfotipos de ovos no exame coproparasitológico e uma grande diversidade morfométrica dos ovos nos helmintos adultos.

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Faliex, Elisabeth. "Les relations hôtes-parasites dans le modèle téléostéens-métacercaires de Labratrema minimus (Trematoda, Bucephalidae)." Perpignan, 1991. http://www.theses.fr/1991PERP0117.

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Gállego, Franco Laia. "Parasitación de Cornu aspersum Müller, 1774 (Helicidae) por metacercarias del género Brachylaima sensu lato Dujardin, 1843 (Brachylaimidae): tratamiento antihelmíntico y consumo humano." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/457698.

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El caracol de consumo humano Cornu aspersum actúa como hospedador intermediario en el ciclo biológico de Brachylaima spp. albergando metacercarias libres en riñón. Su ingestión insuficientemente cocinados permitiría a las metacercarias originar adultos en el intestino humano causando la braquilaimosis, parasitosis con una mortalidad esperada del 5-10%, con casos humanos en Australia. Los objetivos de esta tesis fueron: determinar la prevalencia de metacercarias Brachylaima spp. en C. aspersum de consumo en mercados españoles; estudiar la dinámica de parasitación considerando la localización geográfica de los caracoles y la estacionalidad como factores de riesgo respecto a la exposición humana al parásito; describir la influencia de la importación de caracoles sobre la dispersión geográfica de Brachylaima spp.; evaluar la eficacia del praziquantel (PZQ) frente a metacercarias Brachylaima spp.; desarrollar un método bioanalítico mediante HPLC-MS/MS para determinar cualitativamente y cuantitativamente PZQ en el gasterópodo y evaluar mediante microscopía electrónica de transmisión (TEM) los efectos ultraestructurales producidos por el PZQ en metacercarias tratadas. Se analizó 3710 ejemplares de C. aspersum durante 5 años en mercados españoles [Barcelona (n=2525), Bilbao (n=207), Madrid (n=290), Tudela (n=301), Valencia (n=163) y Zaragoza (n=224)]. Se examinó individualmente el riñón y se registró la carga de metacercarias. Se calculó la prevalencia global (41’97%;95%IC:40’38%-45’56%), por ciudad y por mercado en el caso de Barcelona y la estacionalidad (↑otoño). El modelo de regresión logística que mide la probabilidad de adquirir caracoles parasitados utilizando la ciudad y la estación como predictores (79% de acierto global), mostró riesgo significativo (p=0.001) en interacciones Tudela-Otoño (4.330-78.584) y Barcelona-Otoño (2.551-38.442). Se determinó la prevalencia de metacercarias en caracoles importados de Argelia y Sudáfrica obteniéndose adultos experimentales cuya aproximación específica se realizó mediante análisis morfométrico comparativo con adultos B. mascomai y B. llobregatensis. Se emplearon 18 variables morfométricas aplicándose MANOVA y Análisis de Componentes Principales, mostrando superposición B. llobregatensis/Adultos argelinos y B. mascomai/Adultos sudafricanos. La eficacia de PZQ frente a metacercarias Brachylaima spp. en C. aspersum se evaluó mediante dos ensayos (VICH GL7): de determinación de la dosis adecuada para conseguir una reducción de la carga parasitaria igual o superior al 90% y de confirmación de dosis. Se administró PZQ a los caracoles vía oral en el pienso de engorde. El método analítico HPLC-MS/MS se desarrolló siguiendo la guía EMEA/CHMP/EWP/192217/2009 de la EMA. En el ensayo de determinación de dosis se testaron tres dosis individualmente (n=300, 10 días): 1’2mgPZQ/caracol, 1’8mgPZQ/caracol (eficacia 97’3 %, p<0.001) y 2’4mgPZQ/caracol (eficacia 98’7%, p<0.001). En el test de confirmación de dosis (n=200) se ensayó 2’4 mg/caracol en grupo (10 caracoles/caja, 7 días) (eficacia 94’6%,p<0.001). La prevalencia disminuyó del 68’7% en el grupo control al 10.1% en el grupo tratamiento, p<0.001. La dosis recibida correspondió a 200’2mgPZQ/kg de caracol con concha. En el método analítico se evaluaron la linealidad rangos 0’05-0’8µg/ml y 0’8-6µg/ml (r2=0’99), el límite de cuantificación inferior (0’05 µg/ml), la selectividad, el efecto de arrastre, la exactitud variaciones nominales inferiores al ±20%,, la precisión manteniéndose en el intervalo de 15-20%, la integridad de la dilución, el efecto matriz (%CV=10’86 y %CV=10’01) y la estabilidad. Se determinó cuantitativamente el residuo de praziquantel (n=60) en caracoles tratados (11mgPZQ/g pienso), siendo de 0’093 mgPZQ/g caracol (10% del PZQ teóricamente ingerido). Los efectos ultraestructurales del praziquantel en metacercarias recuperadas de C. aspersum tratados individualmente (1’2 mgPZQ/caracol y 2’4 mgPZQ/caracol) y en grupo (2’4mgPZQ/caracol ad libitum durante 7 días) mostraron pérdida de la orientación característica de los cuerpos celulares tegumentarios T2 y mitocondrias observada en las metacercarias control, alteración mitocondrial y de los cuerpos celulares tegumentarios T2, ya a nivel de las células tegumentarias. La contracción del sistema digestivo fue tan severa que el lumen no pudo apreciarse.
The edible land snail Cornu aspersum acts as second intermediate host in the cycle of Brachylaima sp. trematode, harboring free metacercariae in its kidney. The ingestion of undercooked infected snails by humans allow metacercariae to develop to adult stage in the intestine causing brachylaimiasis. The aims of this dissertation were: to explore the prevalence of Brachylaima sp. metacercariae in C. aspersum intended for consumption in Spanish marketplaces considering geographical localization and seasonality as risk factors and the potential effect of international snail trade on the parasite dispersion, to assess the efficacy of praziquantel (PZQ) against Brachylaima sp. metacercariae, to develop a bioanalytical method by HPLC-MS/MS to quantify PZQ residue, and to assess ultrastructural changes by transmission electronic microscopy (TEM) of PZQ treated Brachylaima metacercariae. A total of 3,710 C. aspersum specimens were analyzed along 5 years in Spain, the overall prevalence was 41.97% (95%CI: 40.38%-45.56%) with a season effect of increasing prevalence from summer to autumn with a logistic regression model with a correct prediction of 79.0%. Studies conducted on prevalence and viability of metacercariae from snails imported to Spain from Algeria and South Africa provided experimental adult specimens which were measured considering 18 variables. Morphometric studies performed through MANOVA and Principal Component Analysis, revealed univariate effects in 13 variables and an overlap between B. llobregatensis/Algerian adults and B. mascomai/South African adults, respectively. In dose determination assays three doses with snail food were individually tested: 1.2 mg PZQ/snail, 1.8 mg PZQ/snail (efficacy 97.3 %, p<0.001) and 2.4 mg PZQ/snail (efficacy 98.7%, p<0.001). In dose confirmation tests the 2.4 mg PZQ/snail dose was group tested being the efficacy 94.6 %, p<0.001; and the prevalence 10.1 %, p<0.001 from 68.7 %. In the analytical method, linearity, lower limit of quantification (0.05 µg/ml), selectivity, carry over, accuracy, precision, dilution integrity, matrix effect and stability were tested and PZQ determined in 60 treated snails (0.093 mg PZQ/g snail). TEM studies revealed that the characteristic arrangement was lost for mitochondria and the T2 secretory bodies, both also showed degeneration, T2 bodies even in the tegumental cell bodies, and the digestive system displayed a strong contraction.

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Correa, Yepes Ana Cristina. "Analyse de linteraction hôte-parasite sous différentes approches évolutives : le système Lymnaeidae (Gastropoda) Fasciolidae (Trematoda)." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20156.

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Les parasites exercent une pression de sélection quasiment universelle. Cette thèse aborde les relations hôte-parasite dans le système Lymnaeidae (Gastropoda) Fasciolidae (Trematoda, douves) sous différents aspects, afin de brosser une image de cette interaction et de son évolution. J'ai tout d'abord établi les relations phylogénétiques entre les espèces de Lymnaeidae, puis retracé l'évolution de différents caractères, tels que la susceptibilité à l'infestation par Fasciola hepatica et F. gigantica. Alors que F. hepatica est un parasite généraliste, capable d'infester des mollusques de presque tous les clades de la famille Lymnaeidae, l'infestation par F. gigantica est plus restreinte à un clade. J'ai ensuite étudié plus finement la coévolution entre le parasite F. hepatica et deux de ses hôtes Lymnaeidae (Galba truncatula et Omphiscola glabra) au sein d'une métapopulation, ce qui a confirmé la stratégie généraliste de F. hepatica. En plus, il semblerait que les mollusques parasités et non parasités de G. truncatula aient des différences génétiques, au moins dans cinq des huit populations étudiées. J'ai caractérisé la diversité génétique de deux espèces de mollusques envahissantes, préférentiellement autogames et impliquées dans la transmission de F. hepatica : Pseudosuccinea columella et Lymnaea sp. On trouve une diversité génétique très réduite, chez ces deux espèces, ce qui pourrait faciliter leur expansion géographique et leur infestation par F. hepatica. Ce travail m'a ensuite conduit à mesurer le temps d'attente avant l'autofécondation et la dépression de consanguinité chez ces deux espèces. J'ai trouvé que ces deux espèces sont caractérisées par une dépression de consanguinité très faible et un temps d'attente nul, ce qui confirme les résultats obtenus lors d'une collaboration dans une étude à plus large échelle. Cette thèse souligne l'importance des études en évolution pour comprendre l'épidémiologie des maladies parasitaires
Parasites constitute a selective pressure to almost all living beings. This thesis addresses the host-parasite interaction in the Lymnaeidae (Gastropoda) Fasciolidae (Trematoda; liver flukes) system through different approaches, with the aim to give a comprehensive image of this interaction and its evolution. First, I established the phylogenetic relationships among Lymnaeidae species, and then mapped the evolution of different characters such as the susceptibility to the infection by Fasciola hepatica and F. gigantica. While F. hepatica is a generalist parasite, capable to infect snails from almost all clades of the Lymnaeidae, infection by F. gigantica is restricted to one clade. Next, I studied the co-evolution between the parasite F. hepatica and two of its intermediate host species (Galba truncatula and Omphiscola glabra) at a finer scale: within a metapopulation. This study confirmed the generalist strategy of F. hepatica. In addition, it seems that parasitized and non-parasitized G. truncatula snails exhibit genetic differences, at least in five out of eight studied populations.I also characterized the genetic diversity of two species of invasive snails involved in the transmission of F. hepatica: Pseudosuccinea columella and Lymnaea sp. We discuss the possible reasons of invasion success in these snails, despite their low genetic diversity, which could facilitate their infection by F. hepatica. Their capacity to respond to parasitism is certainly reduced, all the more that these species are preferential selfers. This work has then led me to measure the waiting time before self-fertilization and inbreeding depression in these two snails. I found that these two species are characterized by low inbreeding depression and present no waiting time, which confirms the results obtained in a collaborative project at larger phylogenetic scale. This thesis strengthens the importance of evolutionary studies to understand the epidemiology of parasitic diseases

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Moore, Revelyn M. "Histochemical and ultrastructural studies of oogenesis, vitellogenesis and eggshell formation in acanthoparyphium spinulosum (trematoda: echinostomatidae)." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1985. http://digitalcommons.auctr.edu/dissertations/3595.

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This investigation presents a composite of the cytolog-ical events of oogenesis, vitellogenesis and eggshell formation at the ultrastructural level in a poorly known echinostomid trematode, A. spinulosum. For comparison, histochemieal methods which demonstrate basic proteins, phenols and phenolase were used to identify reproductive structures which produce eggshell precursors of the quinone-tanning system. It was observed that the tanning, system is localized specifically in the shell globules of vitelline cells and eggshells. Through transmission electron microscopy (TEM), it was observed that organization of the granular endoplasmic reticulum and Golgi complex is associated with synthesis of cortical granules in dveloping oocytes. At the onset of maturation of ova, the cortical granules are characteristically arranged immediately beneath the plasma membrane. The nucleus of mature oocytes have dispersed chromatin, which suggests that oogenesis proceeds as far as the diplotene stage of the first division of meiosis. Furthermore, it was observed that "nucleolus-like bodies" occur in close association with mitochondria in these cells. However, the significance of this phenomenon is not clearly understood. The vitelline follicles contain cells in various stages of vitellogenesis and a number of nurse cells. In contrast to immature cells, maturing vitelline cells are characterized by a well-organized granular endoplasmic reticulum and Golgi complex, which are associated with the synthesis of shell globules. These globules are arranged beneath the plasma membrane of mature cells. These cells also contain copious amounts of lipid droplets and glycogen granules. In addition, it was observed that cytoplasmic extensions of nurse cells form junctional complexes with vitelline cells, suggesting that a mechanism of selective transport exists between these cells. There is evidence that initiation of eggshell formation occurs in the distal ootype and proximal uterus. Reticular secretions from membranous body cells of Mehlis * gland were seen on the inner and outer surfaces of egg capsules in these regions. Granular secretions from dense body cells of Mehlis* gland were also observed adhering to egg capsules in the distal uterus. In contrast to young eggs, the older shells are several times thicker and appear to be blotched with electron-lucid areas, some of which have finely granular cores. It is suggested that the appearance of the older capsules may represent some phase of the tanning process. In summary, egg formation in Acanthoparyphium spinulosum appears to follow the general pattern of most other trematodes. However, when comparing oogenesis and vitellogenesis of A_. spinulosum to those processes in other trematodes, particularly Schistosoma mansoni and Fasciola hepatica, a greater variance was observed in the histochemistry and ultrastructure of mature vitelline cells. The degree of variance among species may be a reflection of differences in environmental factors which affect development of the eggs.

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Martins, Luciana de Fátima Sianto. "Parasitismo por Echinostoma SP (Trematoda: Digenea: Echinostomatidae) em populações pré-colombianas: um estudo de caso." reponame:Repositório Institucional da FIOCRUZ, 2004. https://www.arca.fiocruz.br/handle/icict/4757.

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Os estudos de paleoparasitologia, somados a outros de diversas áreas, podem ajudar no conhecimento sobre origem e evolução de doenças e das relações evolutivas entre parasitos e hospedeiros. Graças a esses estudos sabemos que as zoonoses conhecidas hoje já eram freqüentes em tempos remotos. Neste trabalho foram analisados coprólitos retirados de um corpo naturalmente mumificado encontrado na Lapa do Boquete, Minas Gerais, Brasil, datado entre 600-1200 anos A.P. Encontraram-se ovos de duas espécies de helmintos. O primeiro foi identificado como Necator americanus ou Ancylostoma duodenale.Tal achado soma elementos ao debate sobre a distribuição de infecções por Ancylostomidae na América pré-colombiana. A segunda espécie de ovo foi identificada como Echinostoma sp. Este é provavelmente o primeiro registro de equinostomíase no Brasil. Falso parasitismo foi descartado pela quantificação dos ovos. Esta zoonose, endêmica na região asiática, é vinculada pelos hábitos alimentares. Assim, o encontro de Echinostoma sp. em habitante pré-colombiano no Brasil levanta dúvidas sobre sua presença não só em grupos humanos nativos atuais, que mantiveram maioria de seus hábitos alimentares, como em habitantes das grandes cidades que têm experimentado mudanças de hábitos alimentares e, portanto, adquirido novas infecções parasitárias.

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Fredensborg, Brian Lund, and n/a. "Ecological interactions between the trematode parasite Maritrema novaezealandensis (Microphallidae) and its intermediate hosts in the New Zealand intertidal soft-sediment community." University of Otago. Department of Zoology, 2005. http://adt.otago.ac.nz./public/adt-NZDU20060810.154001.

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Most, if not all, animals will at some stage in their lives encounter parasites. Some of the most widespread and abundant parasites belong to the Class Trematoda. Trematodes often have a substantial negative impact on individual intermediate host ecology. In this thesis, I investigate ecological and evolutionary consequences of the interaction between the microphallid trematode, Maritrema novaezealandensis, and its intermediate snail and crustacean hosts. Parasites often show a heterogeneous spatial distribution pattern in natural animal host populations. In this study, factors determining the spatial distribution of larval trematodes in Zeacumantus subcarinatus were investigated at two spatial scales (within and among bays). The distribution of shorebird definitive hosts explained a significant amount of the variation in the distribution of trematodes among bays. However, within a bay, other factors override the effect of bird distribution. The influence of larval trematodes on reproduction, survival and population density of Z. subcarinatus was investigated using laboratory and field studies. In the laboratory, it was found that larval trematodes induce castration and mortality of Z. subcarinatus. The field study revealed that the local prevalence of trematodes had a significant negative effect on population density of Z. subcarinatus. Through castration, trematodes act as strong selective agents on snail host life history. The effect of trematodes on life history characteristics (reproductive effort, juvenile growth, size at maturity and susceptibility to trematode infections) were investigated among natural populations of Z subcarinatus. Reproductive effort was not higher for uninfected females from populations where the risk of becoming infected was high. However, offspring from those populations were significantly larger, and laboratory-reared juveniles grew significantly faster than conspecifics from other populations. In addition, size at maturity was negatively correlated with trematode prevalence across snail populations. Z. subcarinatus thus adapts to a high local risk of trematode infection by reaching maturity early, thereby increasing the chance of reproducing. The influence of M. novaezealandensis on the survial of the amphipod host, Paracalliope novizealandiae was examined using experimental infections and field observations. The experimental infections demonstrated that parasite-induced mortality was intensity-dependent. The number of M. novaezealandensis per amphipod was too low to significantly induce host mortality in the field. However, the transmission strategy of this parasite allows it to affect host populations during weather conditions ideal for trematode transmission. Trematode strategies in the second intermediate host are important to the understanding of host-parasite co-evolution and the evolution of parasite life cycles. In this study, potential density-dependent effects at the metacercarial stage on size and fecundity of in vitro adult M. novaezealandensis was examined in both experimentally infected P. novizealandiae and naturally infected Macrophthalmus hirtipes. For this purpose, a method to excyst and cultivate M. novaezealandensis metacercariae to an egg producing stage, was developed. Naturally infected M. hirtipes also harboured larval stages of three other helminths. Crowding effects in the two crustacean hosts were expressed as a decreased volume and smaller egg production of in vitro adult M. novaezealandensis. In addition, interspecific interactions among parasite species were observed in crab hosts. The work in this thesis provides evidence that M. novaezealandensis significantly and negatively affect intermediate host ecology. The heterogeneous distribution of trematodes causes differential effects among host populations with subsequent effects on the life history of snail hosts. In addition, this study demonstrates that parasites interact within their second intermediate host with possible implications for the way parasites exploit their hosts.

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Sandland, Gregory J., and University of Lethbridge Faculty of Arts and Science. "Interactions between a brain-encysting trematode and its intermediate host, the fathead minnow." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1999, 1999. http://hdl.handle.net/10133/112.

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Determining the extent to which parasites influence natural populaions of hosts is a major focus of studies in parasitology. Addressing this issue requires host-parasite systems that can be monitored under natural conditions and can be manipulated in the laboratory. I study a model system involving the larval trematode Ornithodiplostomum ptychocheilus that encysts in the brains of its intermediate host, the fathead minnow (Pimephales promelas). This parasite was the most common and abundant of 13 other parasites found in minnows in four boreal lakes in Alberta, Canada. In two of these lakes, prevalence of infection reached 100% in most years and mean intensity ranged from 4 to 40 parasites/host. Field and laboratory experiments showed that the size, the rate of parasite development, and time to encystment were intensity-dependent. However, parasite intensity had no effect on host or parasite survival after a simulated winter in the laboratory. One effect of infection was that infected fish and significantly greater cranial heights and widths than controls. The expression of this parasite-induced alteration in host phenotype was dependent on the size of the fish at infection and on parasite intensity. The cranial distortion led to significantly higher mortality of fish maintained on poor diets and altered the host's phototactic response.
ix, 131 leaves : ill. (some col.), map ; 29 cm.

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Žolt, Horvat. "Helmintofauna slepih miševa (Mammalia: Chiroptera) na području Srbije." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2017. https://www.cris.uns.ac.rs/record.jsf?recordId=104813&source=NDLTD&language=en.

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Analizirana je helmintofauna 127 primeraka slepih miševa na teritoriji Srbije.Sakupljene jedinke su pripadnici 12 vrsta slepih miševa: veliki potkovičar (Rhinolophusferrumequinum Schreber, 1774); tamnoliki brkati večernjak (Myotis mystacinus Kuhl, 1817); mali brkati večernjak (M. alcathoe Helversen & Heller, 2001); šumski brkati večernjak (M. brandtii Eversmann, 1845); južni veliki večernjak (M. oxygnathus Monticelli, 1885); evropski veliki večernjak (M. myotis Borkhausen, 1797); dugodlaki slepi mišić(Hypsugo savii Bonaparte, 1837); obični slepi mišić(Pipistrellus pipistrellus Schreber, 1774); šumski slepi mišić (P. nathusii Keyserling & Blasius, 1839); evropski smeđi dugoušan (Plecotus auritus Linnaeus, 1758); evropski sivi dugoušan (P. austriacus Fischer, 1829) i obični noćnik (Nyctalus noctula Schreber, 1774). Jedinke slepih miševa su sakupljane sa 15 lokaliteta na teritoriji Srbije: Deliblatska peščara, Zasavica, Valjevo, Beograd, Paraćin, Đerdap, Bor, Beljanica, Kučevo, Boljevac, Zaječar, Zlot, Medveđa, planina Tara i Ivanjica u periodu od 2001. do 2009 godine.Izolovano je ukupno 1642 jedinki parazita (787 jedinki metilja, 4 pantljičara i 851 nematoda), razvrstanih u 2 razdela, 1 podrazdel, 3 klase, 3 podklase, 1 nadred, 6 reda, 1 podred, 7 nadfamilija, 11 familija, 9 podfamilija, 12 rodova i 14 vrsta. Identifikovane vrste parazita su: Plagiorchis koreanus(Ogata, 1937), Mesotretes peregrinus (Braun, 1900), Lecithodendrium linstowi (Dollfus, 1931), Prosthodendrium longiforme (Bhalerao, 1926), P. chilostomum (Mehlis, 1831), P. parvouterus (Bhalerao, 1926), Milina grisea(van Beneden, 1873), Capillaria neopulchra (Babos, 1954), Molinostrongylus alatus(Ortlepp, 1932), Strongylacantha glycirrhiza (van Beneden, 1873), Physalopterasp., Litomosa ottavianii (Lagrange & Bettini, 1948), Rictularia bovieri (Blanchard, 1886) i Seuratum mucronatum (Rudolphi, 1809). Kvalitativna i kvantitativna analiza helmintofaune slepih miševa je prvi put rađena na području Srbije, te se date vrste domaćina mogu smatrati novim za sve konstatovane vrste parazita na teritoriji naše zemlje. U ukupnom uzorku 93 (73.23%) jedinki domaćina bilo je invadirano parazitima. Najbrojnije u ukupnom uzorkusu bile vrste P. koreanus, L. linstowii M. alatus, sa dominacijom poslednje. Konstatovano je da pol ne utiče na sastav helmintofaune domaćina. Međutim, konstatovane su promene u kvalitetu i kvantitetu helmintocenoze u pojedinim sezonama.
The helminth fauna of 127 individuals of bats on the territory of Serbia was analyzed. The host samples consisted of 12 bat species: Greater Horseshoe Bat(Rhinolophus ferrumequinumSchreber, 1774); Whiskered Bat (Myotis mystacinusKuhl, 1817); Alcathoe Whiskered Bat (M. alcathoeHelversen & Heller, 2001); Brandt ’s Bat (M. brandtiiEversmann, 1845); Lesser Mouse-eared Bat (M. oxygnathusMonticelli, 1885); Greater Mouse-eared Bat (M. myotisBorkhausen, 1797); Savi ’ s Pipistrelle Bat (Hypsugo saviiBonaparte, 1837); Common Pipistrelle Bat (Pipistrellus pipistrellus Schreber, 1774); Nathusius ’ Pipistrelle Bat (P. BathusiiKeyserling & Blasius, 1839); Brown Long-eared Bat (Plecotus auritusLinnaeus, 1758); Grey Long-eared Bat (P. austriacusFischer, 1829) and Noctule Bat (Nyctalus noctulaSchreber, 1774). Host semples were collected from fifteen localities throughout Serbia: Deliblato sands, Zasavica, Valjevo, Belgrade, Paraćin, Đerdap, Bor, Beljanica, Kučevo, Boljevac, Zaječar, Zlot, Medveđa, Tara mountain and Ivanjica in the period between2001 and 2009. A total of 1642 helminth individuals (787 individuals of digeneans, 4 cestodes and 851 nematodes) were collected from the hosts, classified into 2 phylas, 1 subphyla, 3 classes, 3 subclasses, 1 superorder, 6 orders, 1 suborder, 7 superfamilies, 11 families, 9 subfamilies, 12 generas and 14 species. Fourteen parasite species were identified: Plagiorchis koreanus(Ogata, 1937), Mesotretes peregrinus(Braun, 1900), Lecithodendrium linstowi(Dollfus, 1931), Prosthodendrium longiforme(Bhalerao, 1926), P. chilostomum(Mehlis, 1831), P. parvouterus(Bhalerao, 1926), Milina grisea (van Beneden, 1873), Capillaria neopulchra(Babos, 1954), Molinostrongylus alatus (Ortlepp, 1932), Strongylacantha glycirrhiza(van Beneden, 1873), Physalopterasp., Litomosa ottavianii(Lagrange & Bettini, 1948), Rictularia bovieri(Blanchard, 1886) and Seuratum mucronatum(Rudolphi, 1809). The qualitative and quantitativeanalysis of the helminth fauna of bats were conducted in Serbia for the first time. Therefore all bat species can be considered new hosts for all recorded helminth species on the area of the country. Ninety-three (73.23%) individuals werefound to be infected with helminth parasites. The most numerous helminth species in total sample were P. koreanus, L. linstowiand M. alatus, which is also the most dominant. There is no evidence that the composition of helminth fauna depends on the sex ofthe host. However, some seasonal changes in quality and quantity of helminth community of the host are obvious.

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Ndiaye, Papa Ibnou. "Systématique et Phylogénie de Plathelminthes parasites ("Trematoda et Cestoda"): apport des études ultrastructurales de la reproduction." Doctoral thesis, Universitat de Barcelona, 2003. http://hdl.handle.net/10803/2417.

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El presente estudio constituye una importante contribución al conocimiento de la ultraestructura de la espermiogénesis y del espermatozoide de los Platelmintos parásitos. Los caracteres ultraestructurales de la reproducción, particularmente los del espermatozoide, son de gran utilidad para la Sistemática, la Taxonomía y la Filogenia de diversos grupos zoológicos, entre ellos el de los Platelmintos. Por ello, se ha estudiado ultraestructuralmente la espermiogénesis y el espermatozoide de siete especies de Platelmintos parásitos de distintas familias: cuatro Digénidos [Scaphiostomum palaearcticum Mas-Coma, Esteban et Valero, 1986 (Brachylaimidae), Fasciola hepatica, Linnaeus, 1758 y Fasiola gigantica Cobbold, 1856 (Fasciolidae) y Notocotylus neyrai González Castro, 1945 (Notocotylidae)] y tres Cestodos Cyclophyllidea [Joyeuxiella pasqualei (Diamare, 1893) y Joyeuxiella echinorhynchoides (Sonsino, 1899) (Dipylidiidae) y Taenia parva Baer, 1926 (Taeniidae)].

Los helmintos, aislados tras disección de los hospedadores, han sido procesados según la metodología pertinente para los estudios ultraestructurales a que van encaminados. En el caso de F. gigantica se ha aplicado la técnica citoquímica de Thiéry para evidenciar la presencia de glucógeno en el gameto masculino. En el estudio de F. hepatica, dada la procedencia del material de la rata negra (Rattus rattus), hemos podido diseccionar el hospedador en el laboratorio y aplicar más fácilmente otras técnicas como son: 1) las técnicas inmunocitoquímicas para evidenciar la tubulina en el citoesqueleto del espermatozoide y 2) las de "whole mount" y de microscopía electrónica de barrido destinadas a la observación de espermatozoides enteros. Las técnicas inmunocitoquímicas de inmunomarcaje ultraestructural nos han permitido de detectar la presencia de las tubulinas contenidas en el citoesqueleto del espermatozoide mediante la utilización de anticuerpos monoclonales (anti-alfa-tubulina, anti-beta-tubulina, anti-tubulina acetilada y anti-tubulina tirosinada).

Los resultados obtenidos en relación las especies estudiadas forman parte de las seis publicaciones expuestas en la Memoria.

El estudio de S. palaearcticum es el cuarto trabajo realizado sobre la ultraestructura del gameto masculino en la familia Brachylaimidae y el primero de la subfamilia Ityogoniminae. En el caso de N. neyrai, el presente estudio constituye la primera aportación ultraestructural para la familia Notocotylidae. En la familia Fasciolidae se ha realizado un estudio comparado de la ultraestructura de la espermiogénesis y del espermatozoide de F. hepatica (parásito de Bos taurus en España y de Rattus rattus en Córcega) con la de F. gigantica (parásito de Bos indicus en Senegal). Para el género Joyeuxiella y, por extensión, para la familia Dipylidiidae, se establece el modelo general de la espermiogénesis y del espermatozoide dada la existencia de datos en dos de los tres géneros incluidos en esta familia. En el caso de T. parva, los resultados aportados contribuyen a la determinación de las características ultraestructurales del espermatozoide para las especies de la familia Taeniidae.

Se efectua una completa revisión y discusión al respecto de diversos caracteres ultraestructurales del espermatozoide de los Digénidos, como son las ornamentaciones externas de la membrana y los cuerpos espinosos. Por otra parte, se describe la formación de una expansión citoplasmática dorso-lateral en el transcurso de la espermiogénesis en F. gigantica y F. hepatica. En el caso de los Cestodos, se describe por primera vez la formación de la vaina periaxonemal durante la espermiogénesis de Joyeuxiella spp. Además, ciertos caracteres de la espermiogénesis de los Digénidos y de los Cestodos primitivos como son la presencia de raíces estriadas y de rotación flagelar son igualmente observados respectivamente en los Cyclophyllidea Joyeuxiella spp. y T. parva.

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O'Grady, Richard Terence. "Phylogenetic systematics and the evolutionary history of some intestinal flatworm parasites (Trematoda : Digenea: Plagiorchioidea) of Anurans." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27502.

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Historical structuralism is presented as a research program in evolutionary biology. It uses patterns of common ancestry as initial hypotheses in explaining evolutionary history. Such patterns, represented by phylogenetic trees, or cladograms, are postulates of persistent ancestral traits. These traits are evidence of historical constraints on evolutionary change. Patterns and processes consistent with a cladogram are considered to be consistent with an initial hypothesis of historical constraint. As an application of historical structuralism, a phylogenetic analysis is presented for members of the digenean plagiorchioid genera Glypthelmins Stafford, 1905 and Haplometrana Lucker, 1931. The eight species studied are intestinal parasites of frogs and toads in North, Central, and South America. In a Wagner parsimony analysis of 21 morphological characters with both the PAUP and PHYSYS computer programs, a single phylogenetic tree with a consistency index of 84.8% can be inferred. This suggests strong historical constraint in the evolution of the characters examined. It is postulated that the eight species form a monophyletic group (clade), consisting of two less inclusive clades. Glypthelmins hyloreus and G. pennsylvaniensis comprise one of these clades; G. robustus, G. shastai, H. intestinalis, G. californiensis, G. quieta, and G. facioi comprise the other. G. robustus, found in Bufo marinus in Colombia, is both the southernmost and the most plesiomorphic member of its clade. Glypthelmins californiensis, G. quieta, and G. facioi form a clade, and parasitize frogs in the Rana pipiens complex in Mexico, eastern North America, and Central America, respectively. Glypthelmins shastai and H. intestinalis, the latter of which is the only member of its genus, form a western North American clade, and parasitize Bufo boreas and Rana pretiosa, respectively. The phylogenetic analysis includes a redescription of G. shastai, the synonymy of the genus Haplometrana with Glypthelmins, the redescription of H. intestinali s as G. intestinalis, an emended diagnosis of the genus Glypthelmins, and the first account of the life cycle of G. californiensis. Three aspects of phylogenetic analysis are examined in detail. These are the coding of multistate character trees, the use of parasite data to infer host relationships, and the properties of the Consistency Index and the F-Ratio. It is proposed that the Consistency Index be calculated without non-homoplasious autapomorphic characters. For the present study, this modification gives a value of 76.9%. Using the phylogenetic tree as a general reference system of patterns of common ancestry, it is inferred from developmental studies that (1) there is no conflict between the phylogenetic relationships indicated by only larval or only adult characters, and that (2) the evolution of some of the characters involved certain types of heterochrony. Paedomorphic heterochrony is inferred to have occurred in the evolution of the uterus in G. shastai, H. intestinalis, G. californiensis, G. quieta, and G. facioi. Peramorphic heterochrony is inferred to have occurred in the evolution of the penetration glands in G. facioi, and of the hindbody in H. intestinalis. The relatively longer hindbody of H. intestinalis was experimentally induced to show paedomorphic development by raising specimens of H. intestinalis in Bufo boreas, which is the host of G. shastai, its sister-species. By one year after infection, the relative length of the hindbody is shorter, and is equal to that of the primitive state found in G. shastai. The phylogenetic relationships among the anuran hosts are re-analyzed. There is 80% congruence between them and the postulated phylogenetic tree for their parasites, suggesting strong historical association between the parasite and host groups. This inference of coevolution is further supported by the concordance of the present geographical distributions of the parasites and their hosts with the historical geology of the areas in which they occur. This implies an historical association between the areas and the organisms.
Science, Faculty of
Zoology, Department of
Graduate

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Grewal, Amardeep K. "Digenetic trematodes from marine fishes of Fiji : subfamily Hurleytrematinae (Family Monorchiidae): a review and description of four new species of Hurleytrematoides." Scholarly Commons, 1998. https://scholarlycommons.pacific.edu/uop_etds/2336.

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Four new species of Hurleytrematoides Y amaguti, 1954 are described: H. fl}iensis from Heniochus acuminatus pnd Chaetodon citrinellus, H. prevoti from Chaetodon melannotus; H bartolii from Heniochus acuminatus and H monoceros, and H. zebrasomae from Zebrasoma scopas. The hurleytrematine genera Hurleytrema, Hurleytrematoides, Pseudohurleytrema and Parahurleytrema are briefly discussed and their validity accepted based chiefly on the structure of the male and female terminal structures. Hurleytrema pyriforme Overstreet, 1969 and H. catarinensis Amato, 1982 are transferred to Pseudohur/eytrema as new combinations. The generic diagnosis of Hurleytrematoides is emended to include cirrus with large and extensive spines or small ones with limited distribution, and a spiny or aspinose unipartite terminal organ. A key to the hurleytrematine genera with single testis and their species is given. A parasite-host list of all monorchiid species reported to date is included.

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Dempster, Shiona Jane. "The influence of experimental Plagiorchis nobeli (Trematoda: Plagiorchiidae) infections on the survival and development of Aedes aegypti /." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61868.

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Carlson, Kimberly. "Digenetic trematodes of marine fishes of Jamaica, West Indies." Scholarly Commons, 1992. https://scholarlycommons.pacific.edu/uop_etds/2238.

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Portier, Julien. "Alaria alata (Goeze, 1782) (Platyhelminthes, Trematoda) : étude des différents acteurs du cycle, épidémiosurveillance et développement d’outils de diagnostic »." Thesis, Reims, 2012. http://www.theses.fr/2012REIMP202/document.

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Le parasite Alaria alata (Goeze, 1782) est un trématode qui nécessite trois hôtes obligatoire et qui présente la particularité de pouvoir infester un grand nombre d'espèces animales (oiseaux, reptiles, mammifères) au stade mésocercaire..Depuis que la recherche de trichine par des méthodes de digestion a été rendu obligatoire chez les sangliers chassés dans l'ensemble des pays de l'union européenne, elle a permis également la détection des mésocercaires dans les muscles de ces animaux. L'étude de la répartition des déclarations de sangliers porteurs montre que les cas se situent majoritairement dans l'Est de la France. Le nombre de déclarations en augmentation entre 2007 et 2010 est probablement lié à la sensibilisation des laboratoires à la présence d'A. alata plutôt qu'une réelle émergence. A partir d'une base de données de déclaration dans le Bas-Rhin montre que la répartition spatiale des sangliers porteurs du parasite se limite à la vallée du Rhin bornée par le massif des Vosges soulignant ainsi l'importance des zones humides pour la maintien du parasite. Une relation significative existe entre le portage du parasite et les saisons printemps-été ainsi qu'une émergence réelle du parasite entre 2007 et 2010. Par une approche moléculaire le rôle de Planorbis planorbis et Anisus vortex comme premier hôte intermédiaire a été confirmée in natura lors de l'examen de mollusques. La nature des biotopes des mollusques a été abordée ainsi que leur périodes d'émission des cercaires d'A. alata ce qui explique partiellement la saisonnalité des cas observée chez les sangliers du Bas-Rhin..Des prélèvements de muscles sur 6 sangliers chassés dans des zones de forte circulation du parasite, soumis à une méthode de Baermann modifiée, ont permis de mettre en évidence des taux d'infestation de plus de 1000 mésocercaires pour 100 gr. La distribution des mésocercaires chez le sanglier est très large avec toutefois des localisations ciblées vers les tissus antérieurs au diaphragme. Nous avons également mis en évidence une sensibilité du parasite à la congélation et une longue persistance dans les viandes en décomposition.. A partir de mésocercaires isolées sur sanglier, des infestations sur souris ainsi que des tests de survie in vitro ont été effectués :. Chez les souris, chez certains amphibiens et in vitro, une encapsulation active des mésocercaires a été observée ce qui tend à montrer que le parasite dispose de moyens d'éviter la réaction de l'hôte. Si le parasite (au stade cercaires et mésocercaires) est fortement inféodé aux milieux humides, il est capable de phénomène de transfuge à une grande variété d'hôtes paraténiques qui ainsi participent très largement à son maintien et à sa dispersion
The parasite Alaria alata (Goeze, 1782) is a flatworm which needs three obligatory hosts for its development but its particularity lies in that it can infect a wide number of hosts (birds, reptiles, mammals) at the mesocercarial stage. Since the search of trichinella by pepsinic digestion in the muscles of hunted wild boars has become mandatory in the European union, this analysis has also lead to the detection of Alaria alata in the muscles of these animals. The study of case distributions shows that most of the cases have occurred in the East of France. The number of infected wild boars has increased between 2007 and 2010 which is probably more due to the awareness of laboratories to the presence of A. alata mesocercaria than to a true emergence. Using database for the Bas-Rhin département, we were able to show a geographical cluster of positive wild boars around the Rhine Valley and bordered by the Vosges Mountains, hence showing the importance of wetland areas for the sustenance of the parasite. A significant association between A. alata positivity and the spring and summer seasons was noted as well as a true emergence of the parasite between 2007 and 2010. We then sought to identify the first intermediate snail hosts using molecular tools on snail and cercaria collected in infected areas which lead us to identify two Planorbid species: Planorbis planorbis and Anisus vortex. Search of these two species on different biotopes showed that specific environmental conditions were needed for these species, and therefore the parasite, to be present. We proceeded to test different muscular samples from 6 wild boars using a test derived from the Baermann method. Tests showed the highest parasite burdens ever observed in the literature with several samples over 1000 mesocercaria/100g. Distribution within the carcass is very wide though it appears to be oriented to the tissues anterior to the diaphragm. We also showed that the parasite was sensitive to freezing but long persisting in decaying meat. From the mesocercaria collected on the wild boars, experimental infections were performed on mice and survival tests were done in vitro. In mice, but also in amphibians and in vitro, mesocercaria actively formed an inert capsule which would tend to prove the existence of equipments to evade the host's reactions. The works presented here show two important aspects of A. alata's life cycle: the importance of wetlands for its sustenance and also the parasite's ability to persist in a wide variety of paratenic hosts which participate in its sustainance and dispersal

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Lagrue, Clement, and n/a. "Alternative life-history strategies in the trematode Coitocaecum parvum (Opecoelidae) : effects of environmental factors and within-host competition." University of Otago. Department of Zoology, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080905.111744.

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From simple beginnings, when only one host was required, numerous parasitic organisms have evolved complex life-cycles involving two or more host species. For example, trematode parasites reproduce in vertebrates, their definitive host, but their current life cycle also typically involves two intermediate hosts that were added during the course of evolution. Vertebrates are often considered to be the ancestral hosts of trematodes although other scenarios exist. While multi-host life cycles are observed in distantly related groups of parasites, their evolution remains largely unexplored. In trematodes, while recent phylogenetic studies have shed light on the sequence along which the different hosts were incorporated in the cycle, conditions that favoured the evolution of such complex life cycles can only be hypothesized. However, one opportunity to understand the force shaping the evolution of complex life cycles is provided by the few trematode species in which the classical three-host cycle facultatively reverts to a shorter cycle (i.e. life cycle abbreviation). In this study, the effects of different environmental factors on the life history strategy of the trematode Coitocaecum parvum were investigated using laboratory and field studies. C. parvum is able to abbreviate its life cycle from three to two hosts by maturing early (i.e. progenesis) and producing eggs inside the second intermediate host; both life history strategies occur simultaneously in C. parvum populations. Environmental factors such as predator densities should strongly influence parasite life history strategies. In fact, this study shows that laboratory reared Coitocaecum parvum adopt preferentially the normal three-host cycle when chemical cues from the definitive host are added to their environment, while the shorter cycle is favoured when these cues are absent. However, in nature, multiple environmental factors are likely to be perceived by parasites. Consequently, C. parvum�s ability to adapt its developmental strategy to definitive host densities may be confounded by the complex combination of various environmental parameters. Within-host competition between parasites sharing a common host is also likely to influence individual life history strategies. Parasites could then use alternative life strategies to adaptively respond to intraspecific and interspecific competition. Indeed, this study found that C. parvum preferentially adopts the abbreviated cycle in the presence of competitors. However, in interspecific competition, C. parvum�s strategy also depends upon the competitor species, possibly influenced by the other species� transmission route. Furthermore, intensity of intraspecific competition proved to constrain C. parvum�s ability to use the abbreviated life cycle. Finally, genetic relatedness between co-infecting C. parvum individuals seems to affect parasite life strategy through kin selection: closely related individuals are more likely to adopt the same developmental strategy, when they share a host, than unrelated ones. C. parvum individuals adopting the abbreviated cycle are enclosed within a cyst in their intermediate host and must produce eggs by self-fertilization, the most severe case of inbreeding. It was hypothesized that their offspring would have reduced fitness due to inbreeding depression, therefore selecting against the shorter cycle. However, this study found no difference in the survival and infection success of offspring produced through the abbreviated and normal cycles. Furthermore, no evidence for a genetic basis of life cycle abbreviation was detected: the same proportion of offspring from both reproductive strategies adopted the shorter life cycle. The work in this thesis provides evidence that although life cycle abbreviation provides Coitocaecum parvum with a viable alternative life strategy, numerous factors promote or restrict the adoption of this strategy. While this life history strategy has no detectable effect on parasite fitness, both environmental parameters and within-host competition affect C. parvum life-history strategies, alternatively selecting for either the shorter or normal life cycle. Overall, the complexity of the parasite environment could maintain both developmental strategies in C. parvum populations and, on a broader scale, could have influenced the evolution of complex life cycles in parasites.

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Roberts, Mattew L. "The immune response of carp (Cyprinus carpio L.) to the blood fluke Sanguinicola inermis Plehn, 1905 (Trematoda: Sanguinicolidae)." Thesis, Keele University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267354.

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Stumbo, Anthony D. "Cost and behavioural avoidance of trematode cercariae in fathead minnows." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2012, 2012. http://hdl.handle.net/10133/3221.

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Natural selection should favour host defenses that reduce a host’s exposure to parasites or reduce their negative effects. One strategy that resolves the substantial costs of host immunity and/or tolerance is to avoid infective stages altogether. For fish, behavioural avoidance is well-known for defense against aquatic predators, but it is poorly known for defense against parasites. I used a model system that is amenable to experimental manipulation to test the behavioural avoidance hypothesis for fathead minnows exposed to the larvae of two of their common flatworm parasites. First, I showed that minnows exposed to a liver encysting trematode, Ornithodiplostomum sp. showed an increase in lipid peroxidation, an indicator of oxidative stress, persisting through worm development. Three lines of evidence provided support for the behavioural avoidance hypothesis. First, shoal area decreased in groups of minnows exposed to O. ptychocheilus cercariae compared to those exposed to cues from other aquatic threats. Second, average worm numbers were 50 % lower in fish confined to artificial shoals compared to non-shoaling minnows, indicating that shoaling reduces risk of exposure. The third experiment showed that minnows within the centre of shoal reduced their risk of infection by 67%. Taken together, these results demonstrate a cost of trematode infection on minnows, that minnows can detect infective larvae within the water column, and that social living reduces a hosts’ risk of exposure.
xi, 84 leaves : ill. ; 29 cm

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30

Wallage, Helena Rachelle. "The effects of Plagiorchis elegans (Trematoda: plagiorchiidae) infection on the carbohydrate metabolism of fourth instar Aedes aegypti (DipteraCulicidae) larvae." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0034/MQ64474.pdf.

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31

Mattison, Richard Geoffrey. "Studies on the ultrastructure and biology of paramphistome parasites (Trematoda: Digenea) of ruminants and freshwater gastropods in northern India." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336130.

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32

Gracenea, Zugarramurdi Mercedes. "Contribución al conocimiento de determinados aspectos de la bionomia de Brachylaima ruminae Mas-Coma et Montoliu 1985 (Trematoda: Brachylaimidae)." Doctoral thesis, Universitat de Barcelona, 1986. http://hdl.handle.net/10803/673000.

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Los estudios que sobre ciclos biológicos de Tremátodos Digénidos de la familia Brachylaimidae Joyeux et Foley, 1930 se lleva a cabo desde hace ya años en el Departamento de Parasitología de la Facultad de Farmacia de la Universidad de Barcelona nos condujeron, en su día, al inicio del presente trabajo destinado a prestar una pequeña contribución al conocimiento de la bionomía de una especie concreta de Trematodo perteneciente a la familia anteriormente citada: Brachylaima ruminae Mas-Coma et Montoliu, 1985. El ciclo evolutivo de esta especie de Digénido ha sido dilucidado totalmente por MAS-COMA & MONTOLIU (1978 a, b) y MONTOLIU (1984) tanto en la Naturaleza como experimentalmente en el Laboratorio de nuestro Departamento. La complejidad de este ciclo triheteroxeno terrestre nos situó ante un amplio y atractivo abanico de posibilidades de estudio e investigación, dado que cada uno de los aspectos del ciclo es merecedor en sí mismo de un estudio en profundidad.

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33

Magalhães, Aimê Rachel Magenta. "Efeito da parasitose por trematoda buchephalidae na reprodução, composição bioquímica e índice de condição de mexilhões Perna perna (L.) /." São Paulo (SP), 1998. https://repositorio.ufsc.br/handle/123456789/106475.

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Tese (Doutorado) - Universidade de São Paulo, Instituto de Biociências.
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34

Wallage, Helena Rachelle. "The effects of Plagiorchis elegans (Trematoda : Plagiorchiidae) infection on the carbohydrate metabolism of fourth instar Aedes aegypti (Diptera : Culicidae) larvae." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30763.

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Glucose was present in substantially greater concentrations in whole body extracts of fourth instar Aedes aegypti L. larvae than was trehalose; in contrast, trehalose was more abundant than glucose in haemolymph extracts. Preliminary studies suggested that infection of Ae. aegypti by the entomopathogenic digenean Plagiorchis elegans Rudolphi alters the carbohydrate metabolism of fourth instar larvae. Within 24 hours of cercarial penetration, total body extracts of infected fourth instar larvae exhibited decreased trehalase activity, increased trehalose-6-phosphatase activity, and an accumulation of trehalose in comparison to uninfected larvae. Concentrations of glucose, glycogen and lipids, and the activity of glycogen phosphorylase a were similar in extracts of infected and control larvae. The predominant fatty acids, in both control and infected larvae, were C 18:0, C 18:1 and C 18:3. There were no significant differences in the types and proportions of fatty acids found in control and infected larvae. Parasitic infection is discussed in terms of impaired trehalose metabolism.

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Nkwengulila, Gamba. "Epidemiology and taxonomy of Diplostomum species (Trematoda: Diplostomatidae) infecting fish of Llyn Tegid, North Wales and the Ruvu Basin, Tanzania." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260391.

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This study investigated the epidemiology and taxonomy of Diplostomuni species in the deeper parts of the eye (DPE) of roach Rutilus rutilus (L. ), perch Perca fluviatilis L., ruffe Gymnocephalus cernua (L. ) and gwyniad Coregonus lavaretus (L. ) at Llyn Tegid, North Wales, and in the cranium of catfish Clarias gariepinus (Burchell, 1822) and the vitreous humour of Oreochromis species at Mindu dam and river Ruvu, Tanzania. At Llyn Tegid, two species of Diplostomum metacercariae, large and small forms, coexisted in DPE of perch, ruffe and gwyniad but only one, large forms, occurred in roach. Large forms were distinguished by their large size, oval body tapering at both ends and pseudosuckers at the level of the oral sucker. Small forms were distinguished by their smaller size, oval body with parallel sides and pseudosuckers occurring below the level of the oral sucker. The taxonomy of the two forms was not resolved even after obtaining adults from chickens. Tentatively, small forms keyed close to D. gasterostei Williams, 1966 and large forms to D. volvens Nordmann, 1832. Inadequate identification manuals and remarkable similarity between Diplostonlum species confounded identification. Mean intensity of metacercariae was highest in ruffe and lowest in perch and increased with host size in all hosts. Factors responsible for differences in mean intensity between hosts were discussed. There was no seasonality of occurrence. Recruitment occurred from May - November correlating with water temperatures. Immature metacercariae occurred throughout the period of investigation. Metacercariae were overdispersed in all three hosts. At Mindu and Ruvu two species were present, D. sp. X (1,2) in the cranium of catfish and D. sp. Y in the vitreous humour of Oreochromis sp. D. sp. X (1,2) were distinguished by their elongate body, oval calcareous corpuscles and long hindbody. D. sp. Y were distinguished by a vestigial ventral sucker, glandular Brandes organ, short hindbody and spherical calcareous corpuscles. D. sp. X (1,2) were identified as D. mashonense Beverley - Burton, 1963. Adults cultured in chickens confirmed identification. D. sp. X (1,2) developed to ovigerous adults within 24h. Percent recovery of adults from chickens declined with days p. i. Miracidia developed in eggs in six days. D. sp. Y is considered an undescribed taxon. Prevalence and mean intensity of D. sp. Y in Oreochromis sp. were low and did not fluctuate seasonally. Prevalence of D. mashonense in catfish was similar at Mindu and Ruvu and exhibited no seasonal fluctuations. Mean intensity of D. mashonense in catfish of Mindu fluctuated seasonally, increased with host size and was higher than in catfish from Ruvu. Causes of high intensity and seasonal changes at Mindu were discussed. D. mashonense was overdispersed in catfish at both localities but only data from Mindu fitted the negative binomial model. Small samples and the dynamism of forces creating overdispersion were considered responsible for the situation at Ruvu. Using SEM ciliated-pit and dome-shaped papillae were observed on the surface of metacercariae and adults of D. mashonense . Ciliated-pit papillae occurred only on metacercariae. Dome-shaped papillae, in adults and metacercariae, were aggregated on suckers, excretory and genital atria. Spines were multipointed in adults but single pointed in metacercariae.

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Silva, Patrícia Mirella da. "Estudo da infecção de Bucephalus sp. (Trematoda: Bucephalidae) no mexilhão Perna perna e de algumas reações imunológicas induzidas pelo parasita /." Florianópolis, SC, 1999. http://repositorio.ufsc.br/xmlui/handle/123456789/81289.

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37

Barbosa, Fernando Sergio. "Aspectos da biologia de Zygocotyle lunata (Trematoda: Zygocotylidae) isolado de Biomphalaria straminea (Mollusca: Planorbidae) oriundas de iguatama, Minas Gerais, Brasil." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/BUOS-8GLLEK.

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Malacological collections were carried out in lakes near the São Francisco River or its tributaries in Iguatama (Minas Gerais), in the last trimester of 2009, and second and third trimester of 2010. From 4993 mollusks samples collected, 4307 were alive and forwarded to analysis. From the alive ones, 71 samples (1.65%) were infected by trematodes larvae that, after preliminary morphological characterization, were used for experimental biological studies. Life stages (cercariae, metacercariae, adult parasites, eggs and miracidia) were studied before and afterundergoing the process of fixation, staining and mounting on permanent slides, followed by morphological and morphometric analysis with light microscopy. Anfistoma-like cercariae were found in 14 specimens (0,33%) of Biomphalaria straminea which, after turning into metacercariaon solid substrate, were used to check viability in performing experimental infections in AKR/J mice, Gallus gallus domesticus and Meriones unguiculatus. Viability of metacercaria that encisted in 1, 30 and 120 days was checked; however, those of 150 days could not infect. Animals experimentally infected presented parasite eggs in stools from 30 days post-infection that were used to obtain miracidia for infections of mollusks. The hatching of miracidia happened 21 days after infection. Adult parasites retrieved from the cecum region of experimentally infected animals were analyzed, measured and identified as Zygocotyle lunata(Diesing, 1836). Effects of dexamethasone treatment during the course of experimental infection of Mus musculus were also evaluated. It was verified in animals treated with dexamethasone a reduction of the prepatent period and a higher number of parasites, although with smaller size. Descendants of mollusks collected in Iguatama (B. straminea, Physa marmorata, Pomacea caniculata, Drepanotrema anatinum), Belo Horizonte, MG (B. glabrata), Felixlândia, MG and Recife, PE (B. straminea) were exposed to massive and individual infection with miracidia of Z.lunata, and success was obtained only in B. straminea. This is the first record of B. straminea naturally infected by Z. lunata in Brazil.
Coletas malacológicas foram realizadas em lagoas localizadas próximas ao rio São Francisco ou de seus afluentes em Iguatama, Minas Gerais, no quarto trimestre de 2009, segundo e terceirotrimestres de 2010. De 4.993 exemplares de moluscos coletados, 4.307 estavam vivos e foram analisados. Destes 71 exemplares (1,65%) apresentavam-se infectados por larvas de trematódeos que, após caracterização morfológica preliminar, foram identificadas como cercárias do tipo Equinostoma, Anfistoma e Estrigeocercária. Estágios evolutivos (cercárias, metacercárias, parasitos adultos, ovos e miracídios) foram estudados a fresco e após processo de fixação,coloração e montagem em lâminas permanentes seguida de análise morfológica e morfométrica em microscópio de luz. Cercárias do tipo Anfistoma foram encontradas em 14 exemplares (0,33%) de Biomphalaria straminea, que após formação de metacercária em substrato sólido foram utilizadas para verificação de viabilidade em infecções experimentais de Mus musculus da linhagem AKR/J, Gallus gallus domesticus e Meriones unguiculatus. A viabilidade de metacercárias encistadas a 1, 30, 120 foi verificada, entretanto, as de 150 dias não lograram infecção. Os animais experimentalmente infectados que apresentaram ovos do parasito nas fezes a partir de 30 dias após a infecção, foram utilizados para obtenção de miracídios para infecções de moluscos. A eclosão de miracídios ocorreu em 21 dias deincubação. Parasitos adultos recuperados na região do ceco nos animais experimentalmente infectados foram analisados, medidos e identificados como Zygocotyle lunata (Diesing, 1836). Avaliou-se ainda o efeito da dexametasona no curso da infecção experimental em Mus musculus, verificando-se em animais tratados uma diminuição do período pré-patente e maior quantidade de parasitos recuperados, porém de menor tamanho. Descendentes dos moluscos coletados emIguatama (B. straminea, Physa marmorata, Pomacea caniculata, Drepanotrema anatinum), Belo Horizonte, MG (B. glabrata), Felixlândia, MG e Recife, PE (B. straminea) foram expostos à miracídios de Z. lunata, tendo sido verificado positividades somente em B. straminea. Este é oprimeiro registro de B. straminea naturalmente infectado por Z. lunata no Brasil.

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Leung, Tommy Ling Fong, and n/a. "Interspecific and intraspecific interactions of trematodes parasitising the New Zealand cockle Austrovenus stutchburyi." University of Otago. Department of Zoology, 2008. http://adt.otago.ac.nz./public/adt-NZDU20090105.160127.

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Most organisms are rarely infected with just a single species of parasite and are usually simultaneously infected with a range of species. Thus, the parasite fauna of a host represents an entire community composed of multiple individuals from many different species. In nature, it is within the host that parasites can encounter conspecifics and individuals from other species. As in any ecosystem, while such interactions between parasites can be antagonistic due to competition or conflicting interests, association between different species can also be beneficial. In this thesis, I investigated patterns of associations between parasites in the New Zealand cockle Austrovenus stutchburyi through a combination of descriptive and experimental studies employing both standard ecological field techniques and molecular biology methods. It was found that the presence and infection intensity of various parasites species are not independent of each other. Among cockles, an association was found between two trematode taxa, i.e. between the infection intensity by foot-encysting echinostomes and the metacercariae of Gymnophallus sp. It was also found that the presence of the parasitic copepod Pseudomyicola spinosus was associated with greater infection intensity by the echinostomes but not Gymnophallus sp. While it was postulated that the positive association between the echinostomes and Gymnophallus sp. was due to the latter�s preference to infect cockles that are stranded on the sediment surface as a result of heavy echinostome metacercariae burden in their foot, a field experiment found that Gymnophallus cercariae did not preferentially infect cockles that have been forced to remain above the sediment surface as opposed to those that were forced to remain buried. Meanwhile, the two species of echinostomes known to encyst in the cockle�s foot, Acanthoparyphium sp. and Curtuteria australis, were found to represent cryptic species complexes. The presence of such cryptic species means that it is possible that some potential interspecific interactions are overlooked. A study of the population structure of Gymnophallus sp. found that each cockle contains multiple genetically distinct individuals and that clonal individuals rarely co-occur in the same cockle. This adds to the growing body of evidence suggesting that in addition to acting as a means of reaching the definitive host, the second intermediate host also acts to promote genetic diversity by accumulating cercariae shed by multiple first intermediate hosts in the environment. An experimental infection study conducted with Curtuteria australis cercariae deriving from singly-infected first intermediate hosts revealed that different clonal lineages varied with respect to their contribution to host manipulation. It was found that while certain lineages have a preference for host manipulation, others tend to adopt a "hitch-hiker"-type life history strategy. However, this genetic predisposition was also found to be a phenotypically plastic trait, as the presence of a higher number of manipulators seems to encourage newly-arrived cercariae to become manipulators, regardless of clonal lineage. This thesis provides evidence that patterns of interactions can affect various aspects of parasite life history. Apart from host condition, parasites can also be affected by other parasites. Studying the dynamics of mixed infections can provide informative insights for evolutionary and ecological research.

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Matisz, Chelsea E., and University of Lethbridge Faculty of Arts and Science. "Ornithodiplostomum spp. metacercariae in fathead minnows : migration, site selection, and host response." Thesis, Lethbridge, Alta. : University of Lethbridge, Deptartment of Biological Sciences, 2009, 2009. http://hdl.handle.net/10133/779.

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Site selection, and the means to access specific sites, is a keystone of parasitology. I evaluated migration and site selection behaviours of metacercariae of two congeneric species of strigeoid trematode throughout growth and encystment phases in the fathead minnow. Results showed that pre-encystment stages of Ornithodiplostomum ptychocheilus migrate along specific neural tracts to access sites in the optic lobes of the brain. Conversely, pre-encystment stages of Ornithodiplostomum sp. migrate via direct penetration, or via the vascular system to access visceral organs, especially the liver. Remarkably, both species have a bi-phasic pattern of development, with growth and encystment occurring in unique sites. Finally, I examined patterns of rodlet cell proliferation and maturation in response to growth and encystment phases of O. ptychocheilus. Cell densities were low (<11/mm2) in brain tissue adjacent to 1 and 2 week old metacercaria, but peaked to approximately 210/mm2 at 6 weeks. These results shed new light on the potential function of these enigmatic cells.
x, 125 leaves : ill. ; 29 cm.

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40

Mendes, Mariana de Moura. "Helmintos e ácaros nasais parasitos de Pitangus sulphuratus (Passeriformes: Tyrannidae), bem-te-vi, no Rio Grande do Sul." Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/2316.

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The Great Kiskadee, Pitangus sulphuratus (Linnaeus, 1766) (Tyrannidae), occurs only in the Americas, is distributed from the United States (Texas) to Argentina. It is the most popular bird species of Brazil and Rio Grande do Sul, being easily recognized by its onomatopoeic song, vivid colorations and aggressive behavior in a dispute over territory and when guarding the nest. These birds can be found in a wide variety of habitats such as crop fields, towns, orchards, woods and edge of aquatic environments, such as margins of ponds, streams, rivers and dams. They have skills to identify foods in natural environments and exploring food resources of anthropic origin, which contributes to its efficiency in colonizing urban environments and their abundance in various environments. The Great Kiskadee can be considered an omnivorous species, and its flexibility in their food can influence their helminthofauna, since the majority of gastrointestinal parasites are acquired through ingestion of food. Due to lack of information on parasite biodiversity of P. sulphuratus, this work was developed aimed to characterize and disseminate the helminthofauna and nasal mites that parasites the Great Kiskadee, and to calculate the parameters of prevalence, average intensity and average abundance of parasitism. Were examined 78 specimens of P. sulphuratus belonging to the municipality of Pelotas and adjacent municipalities, among those who came to death at the Center for Wildlife Rehabilitation Center and Triage of Wild Animals (NURFS / CETAS / UFPel) and were run over, collected on the highways. At the Laboratory of Parasitology of Wild Animals, Department of Microbiology and Parasitology, birds were necropsied to collect helminths and nasal mites. Helminths found and their parameters of prevalence (P), average abundance (AM) and average intensity (IM) were Dispharynx nasuta (P = 3.85%, AM = 0.10, IM = 2.66), Acuaria Mayor (P = 7 , 69%, AM = 0.18, IM = 2.33), representatives of the subfamily Capillariinae (P = 10.26%, AM = 0.22, IM = 2.12), Eucoleus sp. (P = 10.26%, AM = 0.38, IM = 3.75), Aproctella sp. (P = 6.41%, AM = 0.08, MI = 1.2), Syngamus sp. (P = 7.69%, AM = 0.26, IM = 3.33), Lophosicyadiplostomum nephrocystis (P = 14.10%, AM = 3.18, MI = 22.54), Lutztrema sp. (P = 3.85%, AM = 0.08, IM = 2), Echinostoma sp. (P = 2.56%, AM = 0.15, IM = 6), Centrorhyncus spp. (P = 48.72%, AM = 3.87, IM = 7.95), and representatives of the order Ciclophyllidae (Cestoda) (P = 2.56%). The nasal mites Ptilonyssus spinosus were found with 12.82% prevalence, AM = 1.13, IM = 8.8, sex ratio 4:2, ♀ / ♂ and Sternostoma longisetosae, 5.13%, 0.13 and 2.5, respectively, all specimens were females. A parasitic association between the two species was observed in only one P. sulphuratus. Pitangus sulphuratus features a new host for helminths Dispharynx nasuta, Acuaria mayor, Capillariinae, Eucoleus sp. Aproctella sp. Syngamus sp. (Nematoda), Lutztrema sp. and Echinostoma sp. (Trematoda). That expands the area of occurrence of A. Mayor and L. nephrocystis for the state of Rio Grande do Sul.
O bem-te-vi, Pitangus sulphuratus (Linnaeus, 1766) (Tyrannidae), ocorre apenas nas Américas, distribui-se dos Estados Unidos (Texas) até a Argentina. É a espécie de pássaro mais popular do Brasil e do Rio Grande do Sul (RS), sendo facilmente reconhecido pelo seu canto onomatopéico, sua coloração viva e comportamento agressivo na disputa de território e guarda do ninho. Estas aves podem ser encontrados em uma ampla variedade de habitats, como campos de culturas, cidades, pomares, orla de matas e em ambientes aquáticos, tais como margens de lagoas, córregos, rios e represas. Apresentam habilidades para identificar alimentos em ambientes naturais e em explorar recursos alimentares de origem antrópica, o que contribui para sua eficiência em colonizar ambientes urbanos e sua abundância em vários ambientes. O bem-te-vi é consideradauma espécie onívora, e sua flexibilidade alimentar pode influenciar na sua helmintofauna, uma vez que a maioria dos parasitos gastrointestinais é adquirida através da ingestão de alimentos. Devido a escassez de informações sobre a biodiversidade parasitária de P. sulphuratus, desenvolveu-se este trabalho com o objetivo de conhecer a helmintofauna e ácaros nasais parasitos do bem-te-vi, bem como determinar os parâmetros de prevalência, abundância média e intensidade média de parasitismo. Foram examinados 78 espécimes de P. sulphuratus provenientes de municípios do RS, dos quais alguns vieram ao óbito no Núcleo de Reabilitação da Fauna Silvestre e Centro de Triagem de Animais Silvestres (NURFS/CETAS/UFPel) e outros recolhidos mortos por atropelamento nas rodovias. No Laboratório de Parasitologia de Animais Silvestres, Departamento de Microbiologia e Parasitologia, Instituto de Biologia, Universidade Federal de Pelotas, as aves foram necropsiadas para coleta de helmintos e ácaros nasais. Os helmintos encontrados e respectivos parâmetros de prevalência (P), abundância média (AM) e intensidade média (IM) foram: Dispharynx nasuta (P= 3,85%, AM=0,10, IM=2,66), Acuaria mayori (P= 7,69%, AM=0,18, IM=2,33),representantes da subfamília Capillariinae (P= 10,26%, AM=0,22, IM=2,12), Eucoleus sp. (P= 10,26%, AM=0,38, IM=3,75), Aproctella sp. (P= 6,41%, AM=0,08, IM=1,2), Syngamus sp. (P= 7,69%, AM=0,26, IM= 3,33), Lophosicyadiplostomum nephrocystis (P= 14,10%, AM=3,18, IM=22,54), Lutztrema sp. (P= 3,85%, AM=0,08, IM=2), Echinostoma sp. (P= 2,56%, AM=0,15, IM=6), Centrorhyncus spp. (P= 48,72%, AM=3,87, IM=7,95) e representantes da ordem Cyclophyllidea (P= 2,56%). Os ácaros nasais encontrados foram Ptilonyssus spinosus com 12,82% de prevalência, AM=1,13, IM=8,8, razão sexual 4:2, ♀/♂ e Sternostoma longisetosae, 5,13%, 0,13 e 2,5, respectivamente, todos os exemplares eram fêmeas. A associação parasitária entre essas duas espécies de ácaros foi observada em apenas uma ave. Este achado caracteriza o primeiro relato de P. spinosus e S. longisetosae em P. sulphuratus e amplia a distribuição geográfica destas espécies, sendo a primeira ocorrência de S. longisetosae na região neotropical e primeira citação de P. spinosus no Rio Grande do Sul, Brasil. Pitangus sulphuratus caracteriza um novo hospedeiro para os helmintos Dispharynx nasuta, Acuaria mayori, Capillariinae, Eucoleus sp., Aproctella sp., Syngamus sp. (Nematoda), Lutztrema sp. e Echinostoma sp. (Trematoda). Amplia-se a área de conhecimento de ocorrência de A. mayori, e L. nephrocystis para o estado do Rio Grande do Sul.

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Zamparo, David. "Phylogenetic systematic analysis of the Neodermata (Platyhelminthes) and Aspidobothrea (Trematoda: Neodermata) with investigation of the evolution of the quinone tanned eggshell." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63245.pdf.

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42

Garcia, Juberlan Silva. "Avalia??o bioqu?mica, hematol?gica e histopatol?gica de ratos wistar (Rattus norvegicus) Infectados Experimentalmente Por Echinostoma paraensei (Trematoda: Echinostomatidae)." Universidade Federal Rural do Rio de Janeiro, 2010. https://tede.ufrrj.br/jspui/handle/jspui/2182.

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The trematode Echinostoma paraensei parasitizes the small intestine of rodents, being its natural definitive host Nectomys squamipes. In spite of the great importance of echinostomatides, there are few studies on morphology, biology and physiology of E. paraensei and its interaction with their intermediate and definitive hosts. In the present study 50 Rattus norvegicus (Wistar),adult females were used, 35 were individually infected with 150 E. paraensei metacercariae (Sumidouro strain) and 15 were maintained uninfected, as control group. Weekly, seven infected and three uninfected rodents were euthanized using CO2.The blood was collected to hematological analysis, and serum obtained by centrifugation and used to aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), bilirubin, glucose, total proteins and fractions determinations. Fragments of liver were collected to glycogen determination and histophatological analysis. Adult worms were loaded until third week of infection, being the higher number of worms loaded at first week of inection. The hepatocytes had rounded edges, with signs of impaired nuclear, mild infiltration of polymorphonuclear and sinusoids slightly expanded. The hepatocytes were vacuolated with discrete perivascular and periportal lymphocytic infiltration. The serum biochemical parameters analyzed were increased at the first week of infection, varying onward. Hematological analysis revealed the development of normocytic and normocromic anaemia with anisocytic alteration. In the white blood cells, only a leukopenia was observed at the third week of infection. The present results are discussed.
O tremat?deo Echinostoma paraensei ? um parasito de intestino delgado de roedores, sendo seu hospedeiro definitivo natural Nectomys squamipes. No presente estudo, foram utilizadas 50 f?meas adultas de Rattus norvegicus (Wistar), 35 animais infectados individualmente com 150 metacerc?rias de E. paraensei (linhagem Sumidouro) e 15 animais n?o infectados (controle). Semanalmente, sete animais infectados e tr?s animais controle foram submetidos ? eutan?sia com CO2. O sangue foi coletado para an?lise hematol?gica, e o soro obtido por centrifuga??o, para as determina??es de aspartato aminotransferase (AST), alanina aminotransferase (ALT), gamaglutamiltransferase (GGT), fosfatase alcalina (ALKP), bilirrubina, glicose, prote?nas totais e fra??es. Fragmentos de f?gado foram coletados para a determina??o de glicog?nio e para a an?lise histopatol?gica. Vermes adultos foram recuperados at? a terceira semana de infec??o, sendo o maior n?mro de vermes recuperados na primeira semana. Os hepat?citos apresentavam-se com bordos arredondados e alguns sinais de comprometimento nuclear, infiltra??o por polimorfonucleares nos sinus?ides, vacuoliza??o, discreta infiltra??o linfoplasmocit?ria perivascular e periportal com poucas c?lulas mononucleares presentes na luz do ducto biliar, alguns hepat?citos estavam hipotrofiados. As an?lises hematol?gicas revelaram o desenvolvimento de uma anemia normoc?tica normocr?mica, com anisocitose. N?o foram observadas altera??es significativas na s?rie branca, havendo apenas uma leucopenia na terceira semana de infec??o. Os resultados obtidos s?o discutidos.

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43

Augot, Denis. "Générations rédiennes de Fasciola hepatica Linné, 1758 (Trematoda : Fasciolidae) chez Lymnaea truncatula Müller, 1774 (Gastropoda : Lymnaeidae) : Identification sur la productivité parasitaire." Limoges, 1998. http://www.theses.fr/1998LIMO0006.

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Des etudes experimentales sur les groupes rediens de deux trematodes, fasciola hepatica and f. Gigantica, ont ete realisees afin de rechercher des parametres qui permettent leur identification et d'etudier leur productivite cercarienne. Huit dimensions corporelles et pharyngiennes ont ete suivies jusqu'au 49#e jour d'experience chez 964 redies vivantes de f. Hepatica provenant de lymnaea truncatula soumises a des infestations monomiracidiennes individuelles. Ces mesures ont ete effectuees chez des mollusques chez lesquels la premiere redie de premiere generation (redie r1a) se developpe normalement au cours de l'infestation (developpement typique), ou bien meurt au cours de la 2#e semaine apres sa sortie du sporocyste (developpement atypique). De tous les parametres etudies, c'est la largeur de la lumiere pharyngienne qui est la plus interessante pour differencier les groupes r1a, r1b, r2a et r2b/r3a. Une analyse factorielle discriminante n'a ete realisee qu'avec les redies a developpement typique en utilisant les huit parametres et deux equations : elle demontre que 95 % des redies typiques sont affectees correctement a leur groupe. Les dimensions relevees pour chaque groupe redien de f. Hepatica presentent des variations lorsque le nombre de miracidiums mis au contact de chaque mollusque augmente ou si les redies sont mesurees apres leur immersion dans un fixateur histologique. Les redies de f. Gigantica montrent aussi des variations dans leurs dimensions pharyngiennes en relation avec le groupe redien etudie. La productivite cercarienne de chaque groupe redien a ete evaluee en relation avec le mode du developpement redien (typique, ou atypique) chez des mollusques infestes chacun par un seul miracidium de f. Hepatica. Si la redie r1a reste en vie au cours du cycle parasitaire, les cercaires sont formees par les lots r1b (28 %) et r2a (63 %) jusqu'au 63#e jour d'experience. Si cette redie meurt, c'est le lot r1b qui produit la plupart des cercaires (69 %). Si on maintient ces redies dans des conditions in vitro, des redies filles se forment dans des redies parentales, agees de 14 a 32 jours lors de leur mise en culture, alors que des cercaires sont produites dans des redies plus agees lors de leur mise en culture. Les cercaires de f. Hepatica sont au nombre de 53 a 57 en moyenne chez les mollusques avec une infestation monomiracidienne individuelle, et correspondent a 16,8 % des morulas intra-rediennes. Le nombre des sensilles peri-orificielles augmente depuis les groupes r1a/r1b jusqu'aux redies r2b/r3a. Cet accroissement numerique se retrouve chez les deux fasciola et la seule difference entre ces deux trematodes concerne le nombre plus important de sensilles dans le groupe r2b/r3a de f. Gigantica. Nos investigations demontrent l'existence de differences dans la morphometrie, la chetotaxie et la productivite cercarienne des quatre groupes rediens observes chez l. Truncatula. Ces criteres permettent l'identification precise des deux premieres generations rediennes de f. Hepatica et de f. Gigantica.

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Werneck, Max Rondon [UNESP]. "Helmintofauna de Chelonia mydas necropsiadas na base do Projeto Tamar-Ibama em Ubatuba, Estado de São Paulo, Brasil." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/87812.

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Universidade Estadual Paulista (UNESP)
O presente estudo relata o resultado da análise parasitológica de 62 exemplares juvenis da espécie Chelonia mydas (L.) necropsiadas no Centro de Reabilitação de Tartarugas Marinhas do Projeto TAMAR-IBAMA na região de Ubatuba, Litoral Norte do Estado de São Paulo, Brasil. Trinta e três animais apresentaram parasitas da classe Trematoda das seguintes espécies: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) e Metacetabulum invaginatum (Metacetabulidae). A prevalência variou de 3 a 66,7%, sendo as espécies N. travassosi, D. proteus e M. invaginatum, aquelas de maior prevalência nos animais estudados. A intensidade média de infecção foi maior na espécie da família Metacetabulidade (80,2) em relação às famílias Angiodictyidae (35,7) e Pronocephalidae (7,3). Em 13 (39,4%) animais o parasitismo foi monoespecífico, com predomínio das espécies N. travassosi e D. proteus. Por outro lado, em 20 (60,6%) tartarugas foi observada associação entre parasitas, sendo encontrado 2, 3, 4 ou 5 parasitas, sendo as freqüências desta associação de 33,3%, 0,06%, 0,18% e 0,03%, respectivamente. Observamos associação entre sinais de debilidade e carga parasitária (p = 0,03).
A parasitological survey of 62 juvenile specimens of the Chelonia mydas (L.) necropsied in the Centro de Reabilitação de Tartarugas Marinhas of the Projeto TAMAR-IBAMA, Ubatuba city, North Coast of the São Paulo State, Brazil, is presented. Thirty three animals were parasitized by flukes of the following species: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) and Metacetabulum invaginatum (Metacetabulidae). The prevalence varied from 3 to 66.7%, and the species N. travassosi, D. proteus and M. invaginatum, presented the higher prevalence among the studied animals. The mean intensity of infection was higher in the species of the family Metacetabulidade (80.2) in comparison to the families Angiodictyidae (35.7) and Pronocephalidae (7.3). In 13 (39.4%) animals the parasitism was monospecific, and the species N. travassosi and D. proteus were predominates. On the other hand, in 20 (60.6%) sea turtles an association among parasites was observed. It was found 2, 3, 4 or 5 parasites and the frequencies of this association were 33.3%, 0.06%, 0.18% and 0.03%, respectively. The relation between signs of weakness and mean intensity of infection was also observed (p = 0.03).

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45

Yost, Marlena Catherine. "The study of the life cycle of Bolbophorus damnificus and its pathology in the channel catfish (Ictalurus punctatus)." Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-03132008-095916.

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46

Alba, Menendez Annia. "Comparative biology of susceptible and naturally- resistant Pseudosuccinea columella snails to Fasciola hepatica (Trematoda) infection in Cuba : ecological, molecular and phenotypical aspects." Thesis, Perpignan, 2018. http://www.theses.fr/2018PERP0055/document.

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Pseudosuccinea columella est un des principaux hôtes intermédiaires de Fasciola hepatica, un trématode cosmopolite infectant l’Homme et les animaux domestiques et sauvages, et transmis par des mollusques d’eau douce. L’existence exclusive à Cuba de populations de P. columella qui sont sensibles et naturellement résistantes (encapsulation hémocytaire du parasite) à l’infection par F. hepatica offre un modèle Mollusque-Trématode très intéressant en termes de biologie évolutive, de santé humaine et de stratégies de contrôle vectorielle. L’étude des aspects écologiques, moléculaires et phénotypiques est essentielle pour comprendre les particularités de ce système. Ainsi, nos résultats ont montré que les mollusques sensibles et résistants partagent des exigences écologiques similaires mais chez les résistants la distribution est limitée aux localités avec des eaux acides et peu dures (pH/dureté totale (DT), 6-6.5/4°-10°d) et une richesse des communautés de mollusques très faible, ceci semblant indiquer coût élevé à la résistance. La comparaison de traits d’histoire de vie en laboratoire a permis de confirmer une haute tolérance aux variations de pH/DT de l’eau chez les mollusques résistants mais a montré également une diminution du potentiel reproductif des souches résistantes par rapport aux sensibles. Sur la base de ces observations, des approches «omiques» comparatives ont été entreprises entre souches sensibles et résistantes. Ce travail de thèse nous a aidé à comprendre les particularités de ce modèle hôte-parasite, mais présente également une avancée en termes d’utilisation de la résistance de P. columella à des fins de contrôle de la transmission parasitaire
Pseudosuccinea columella is one of the main intermediate hosts of Fasciola hepatica, a cosmopolitan snail-borne trematode that affects humans, livestock and wildlife. The occurrence in Cuba of susceptible and naturally-resistant populations of this species to F. hepatica infection (host’s hemocytes encapsulate the parasite upon penetration) offers an interesting Mollusca - Trematoda model with applications on evolutionary biology, health sciences and vector control strategies. Thus, here we explored different ecological, molecular and phenotypical aspects of this system to better understand P. columella resistance. We determined that while susceptible and resistant snails share similar ecological requirements, resistant populations occurred only at low pH (6.5-6.5) and total hardness (TH; 4°-10°d) waters, with low snail species richness, suggesting a high ecological cost of resistance. Comparison of life history traits between susceptible and resistant snails, experimentally-reared at low or common pH/TH conditions, showed that resistant populations display higher tolerance to pH/TH variations and a lower reproductive potential. To gain more insights on the molecular bases of the features associated to resistance in P. columella, we performed comparative “omics” approaches on naïve snails from both phenotypes at whole snail level (RNAseq) and at the albumen gland level (2D-electrophoresis). This thesis presents the latest efforts to broadly characterize this model, which constitute building steps for the comprehension of P. columella resistance and for its application to tackle parasite transmission

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Vazquez, Perera Antonio A. "Interaction hôte – parasite en contexte insulaire : relations entre Fasciola hepatica (Trematoda) et les mollusques Galba cubensis et Pseudosuccinea columella (Gastropoda) sur l’île de Cuba." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS084/document.

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Les interactions hôte – parasites sont des systèmes qui affectent probablement la totalité des êtres vivants et constituent un facteur clé dans la compréhension de la dynamique des maladies infectieuses. On a abordé cette problématique en utilisant le système Fasciola hepatica/Lymnaeidae dans sur l'île de Cuba. Cette thèse utilise une approche basée sur différentes disciplines de la biologie comme l’écologie des populations (distribution et abondances de mollusques hôtes intermédiaires), l'écologie parasitaire (données de prévalences naturelles de parasites chez les hôtes), la génétique des populations en utilisant des marqueurs microsatellites (tant pour le parasite que pour les mollusques hôtes), et des études de susceptibilité et compatibilité douve/limnée.En ce qui concerne la diversité génétique du parasite, une très haute diversité et une forte probabilité d’allofécondation ont été observées. En revanche, on n’a pas trouvé de différentiation significatives entre souches. Les taux d’infection chez le bétail sont très élevés.Pour ce qui est de la biologie des populations des limnées hôtes, on a cartographié la distribution des deux espèces présentes à Cuba : Galba cubensis qui est très répandue et Pseudosuccinea columella qui n'est présente que dans la partie centre-occidentale. Nous avons mis en évidence des différences concernant les types d’habitats préférés pour chaque espèce : G. cubensis est plus plastique écologiquement et se retrouve beaucoup plus dans les sites anthropisés.L'étude des compatibilités douve/mollusque a révélé l’existence de populations avec une résistance naturelle à l’infection par F. hepatica chez la limnée P. columella. Ces populations sont génétiquement différenciées des populations sensibles. La plupart des populations sensibles sont monomorphes avec le même haplotype très répandu. Par contre, on a observé une diversité génétique plus importante chez G. cubensis qui suggère un temps évolutif plus ancien à Cuba. L’échantillonnage fait dans une aire de où la fasciolose sévit fortement chez le bétail a révélé un très faible taux d’infection naturel chez les limnées, mais avec de fortes variations d'intensités. Différentes combinaisons douve/limnée sympatriques et allopatriques testées expérimentalement ont montré une compatibilité supérieure de G. cubensis qui suggère une meilleure adaptation aux souches de F. hepatica cubaines.Les résultats obtenus montrent que la compréhension de la dynamique des maladies infectieuses ainsi que leur contrôle doivent s’appuyer sur des connaissances très solides de la biologie, écologie, génétique et évolution des systèmes hôtes – parasites
Host – parasite interactions are biological systems that probably affect every living being. It also constitute a key factor in the understanding of infectious diseases. This subject has been studied using the Fasciola hepatica/Lymnaeidae system in the insular environment of Cuba. This thesis makes a biological multidisciplinary approach through population ecology (distribution and abundance of intermediary hosts snails), infection rates estimations of parasites in their hosts, population genetics using microsatellites markers (for both parasite and snails hosts), and studies of susceptibility and compatibility fluke/snail.The genetic diversity of the parasite is characterized by high values of diversity as well as probability of cross fertilization. However, we failed to detect significant differences between the strains but a highly infection rate is shared in cattle.Regarding the lymnaeid snails, the distribution of the two occurring species is mapped showing that Galba cubensis is widely distributed while Pseudosuccinea columella only exists in central-western Cuba. Both snail species differ in preferred habitat types and G. cubensis displays a higher ecological plasticity commonly observed in heavily human-transformed sites.Differences in host-parasite compatibilities have been revealed. It has been noted the existence of some populations of P. columella with a natural resistance to F. hepatica infection which display a marked differentiation of their population genetic structure compared to susceptible populations. Most susceptible populations are monomorphic with a very common haplotype in Cuba. Conversely, we observed a higher diversity in G. cubensis indicating a larger evolutionary time in Cuba. The sampling conducted in a fasciolosis endemic area revealed very low prevalences in the snail populations. However, strong variation in parasite mean intensity within individuals supports the high infection rates observed in cattle. Different sympatric and allopatric fluke/snail combinations were experimentally tested in which G. cubensis proved to be more compatible and suggest a better adaptation to the circulating F. hepatica in Cuba.Our results show that the understanding of infectious diseases’ dynamics and their effective control must strictly rely in a full knowledge of the biology, ecology, genetics and evolution of host – parasite systems

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Butcher, Bradley J. "Identification and isolation of microsatellite loci from the Trematode Echinostoma Trivolvis for use in interspecific and intraspecific variation studies." Scholarly Commons, 2010. https://scholarlycommons.pacific.edu/uop_etds/750.

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The aim of this project was to study the population genetics of Echinostoma trivolvis, a parasitic trematode that uses multiple hosts in its lifecycle and has a significant impact on amphibian populations. Microsatellite markers were to be identified and isolated because of their highly variable nature and reported ease of use with PCR. Parasite DNA was extracted from planorbid snails from several locations within California including: Point Reyes National Seashore, Lake Tahoe, and the San Francisco Bay Area. In addition, parasite samples were obtained from Manitoba, Canada. Several microsatellites were identified and 29 PCR primers sets were designed, six of which were capable of amplifying consistently. Sequencing other published molecular markers, COl, NDl, and ITS, unveiled intriguing phylogenetic relationships and potential cryptic species. The echinostome population in central California, as a result of this project, may be much more diverse than has long been reported in the literature.

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BOMFIM, Tatiane Cristina dos Santos. "Avalia??o do perfil glic?dico e da biologia reprodutiva de Biomphalaria glabrata (Mollusca) experimentalmente co-infectada por Angiostrongylus cantonensis (Nematoda) e Echinostoma paraensei (Trematoda)." Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/1571.

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The interaction between intermediate hosts and helminths can cause metabolic and reproductive changes in the host snail, they start using their reserves to maintain its vital functions, immune system activation, repair of tissue damage and also to supply the necessary energy for the parasites development. Investigations of co-infection by different helminths can provide essential information about the biology of their co-existence. Our aims are investigate the reproductive changes, evaluate the activity of lactate dehydrogenase and the concentrations of glucose in the hemolymph and glycogen in the digestive gland complex and cephalopedal mass, and also verify histological and histochemical changes of Biomphalaria glabrata experimentally co-infected with Echinostoma paraensei and Angiostrongylus cantonensis. Five groups of snails i.e. uninfected, with single and double infections, either E. paraensei first (E+A) or A. cantonensis first (A+E) were followed; three times a week during four weeks the numbers of egg masses, eggs and hatched snails were counted. Histological and histochemical samples of the ovotestis, albumen gland, digestive gland complex and cephalopedal mass were collected after four weeks as well samples for the biochemical analysis. The number of egg masses/snail, eggs/snail and hatched snails showed significant differences comparing the control group to all infected groups, especially in group E + A, with the majority of values of parameters analyzed lower than 50% of those observed for control snails. A significant decrease in glucose levels and glycogen content, in contrast an increase of lactate dehydrogenase activity was observed in the infected snails. These results indicate intense energy demand that takes the snail increasing the anaerobic degradation of carbohydrates in the infected snails to obtain energy in an attempt to maintain homeostasis. The histological analysis showed that presence of both parasites in the all organs analyzed and the parasites were associated with cell disorganization.
A intera??o entre hospedeiros intermedi?rios e helmintos pode causar altera??es metab?licas e reprodutivas no molusco hospedeiro, que come?am a usar suas reservas para manter as fun??es vitais, na elabora??o de resposta imunol?gica e repara??o de danos teciduais e tamb?m para compensar a drenagem de nutrientes/energia pelos parasitos em desenvolvimento. Investiga??es sobre as co-infec??es por helmintos de esp?cies diferentes podem fornecer informa??es essenciais sobre a biologia da sua co-exist?ncia, refletindo aspectos mais pr?ximos ?queles que encontramos em condi??es naturais. Nossos objetivos foram investigar as altera??es reprodutivas, avaliar a atividade da lactato desidrogenase e as concentra??es de glicose na hemolinfa e glicog?nio no complexo gl?ndula digestiva-g?nada e massa cefalopediosa, e tamb?m verificar altera??es histol?gicas e histoqu?micas de Biomphalaria glabrata experimentalmente co-infectados com Echinostoma paraensei e Angiostrongylus cantonensis. Cinco grupos de moluscos (n?o infectados, com infec??es simples (Echinostoma paraensei ou Angiostrongylus cantonensis) e dupla, seja E. paraensei primeiro (E + A) ou A. cantonensis primeiro (A + E)) foram acompanhados; tr?s vezes por semana durante quatro semanas o n?mero de massas de ovos, n?mero de ovos e n?mero de moluscos eclodidos foram contados. Amostras para a an?lise histol?gica e histoqu?mica do ovoteste, gl?ndula do alb?men, complexo gl?ndula digestiva e massa cefalopediosa foram coletadas ap?s quatro semanas, assim como amostras para a an?lise bioqu?mica. O n?mero de massas de ovos/molusco, ovos/molusco e moluscos eclodidos dos moluscos infectados apresentaram diferen?as significativas quando comparados com o grupo controle, especialmente no grupo E + A, cuja a maioria dos valores dos par?metros analisados foi inferior a 50% dos valores observados para os moluscos controle. Um decr?scimo significativo nos n?veis de glicose e de glicog?nio, em contraste com um aumento de atividade da lactato desidrogenase foi observado nos exemplares infectados. Estes resultados indicam que a demanda de energia intensa leva o molusco infectado ao aumento da degrada??o anaer?bia de carboidratos para obten??o de energia buscando atender ao aumento da demanda energ?tica, numa tentativa de manter a homeostase glic?mica, por?m redu??es significativas s?o observadas. As an?lises histol?gicas e histoqu?micas mostraram a presen?a de ambos os parasitos nos ?rg?os analisados associados com intensa desorganiza??o celular.

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50

Wetzel, Jeff A. "A review of the family Gyliauchenidae Ozaki, 1933 (Trematoda: Digenea) with notes on a collection from Suva, Fiji, and a description of three new species." Scholarly Commons, 1994. https://scholarlycommons.pacific.edu/uop_etds/2259.

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