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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Morfologia de ovos, larvas e adultos de Paratanaisia bragai (Santos, 1934) Freitas, 1959 (Digenea, Eucotylidae) e histopatologia do rim de Columba livia (Gm.) infectado / Morphology of eggs, larvae and adult of Paratanaisia bragai (Santos, 1934) Freitas, 1959 (Digenea, Eucotylidae) and histopathology of the kidney Columba livia infected

XAVIER, Vanessa Barreto 24 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-06T20:04:45Z No. of bitstreams: 1 2015 - Vanessa Barreto Xavier.pdf: 10480934 bytes, checksum: dcefb748f49bc38601b8bbc19c70ebc8 (MD5) / Made available in DSpace on 2017-06-06T20:04:45Z (GMT). No. of bitstreams: 1 2015 - Vanessa Barreto Xavier.pdf: 10480934 bytes, checksum: dcefb748f49bc38601b8bbc19c70ebc8 (MD5) Previous issue date: 2015-02-24 / CAPES / Paratanaisia bragai is a digenetic that reaches sexual maturity in the collecting ducts of domestic and wild birds, and larval development using the snail Subulina octona or Leptinaria unilamellata. The embryonated eggs are released with the waste products of the definitive host and the infection settles in the snail by ingestion of these. After hatching, the miracidium, develop inside the snail two sporocysts generations, cercariae and metacercariae. The definitive host acquires infection by ingestion of parasitized snail. The present study was aimed to identify the action of the parasite on the kidney of pigeons, Columba livia, through histology, and the morphometry, morphology and ultrastructure using light microscopy, scanning electron and transmission of the egg, larval stages (miracidium , cercariae and metacercariae) and adult helminth P. bragai. The adults pigeons were obtained near the Central de Abastecimento do Estado do Rio de Janeiro S.A, Iraj?, Munic?pio do Rio de Janeiro. After parasitological examination in the laboratory, to check infection, the pigeons infected were necropsied to collect helminth and infected kidney. The pigeons were used as uninfected controls. The experimental protocols were approved by the ethics committee on research UFRRJ. Histopathology showed dilatation of the renal tubules, with mononuclear inflammatory cells, formation of papilliform structure projecting into the tubular lumen and metaplasia of the epithelium of the collecting tubule walls, from simple cubic in the tubules uninfected to pseudostratified in infected kidney with P. bragai. The eggs are elliptical, with operculum at the anterior end and a knot at the posterior end, abopercular region. The eggshell is rough and composed of three layers: inner, middle and outer with thicknesses and different electrondense. The miracidium is elongated, with terebratorium the anterior end and body covered with cilia. The cercariae have cylindrical body that tapers slightly in the posterior region. The tegument is rough, the oral sucker is subterminal, the acetabulum stands in the middle third of the body. Papillae were observed around the oral sucker. A similar rudimentary tail structure was observed in some cercariae. The metacercariae observed through histological sections visualized the oral sucker, acetabulum, scales and cyst that consist of three layers, inner, middle and outer, of different thicknesses. The presence of the layers was confirmed by visualization of histological sections of metacercariae in scanning electron microscopy. The adult parasite is elongated and flattened body with oral sucker, pharynx, vitelline glands extending to the region of cecal bifurcation and then the median region of the body. The genital pore visualized a structure that is everted the cirrus in rosette form. In the adult stage the tegument is covered with scales of various types; simple scales, with two, three, four, five and seven divisions, a characteristic that may contribute to ratify the taxonomic classification of the parasite. / Paratanaisia bragai ? um digen?tico que atinge a maturidade sexual nos ductos coletores de aves dom?sticas e silvestres, e para o desenvolvimento larval utiliza o molusco Subulina octona ou Leptinaria unilamellata. Os ovos embrionados s?o liberados com os produtos de excre??o do hospedeiro definitivo e a infec??o no molusco se estabelece pela ingest?o destes. Ap?s a eclos?o do mirac?dio, desenvolvem-se no interior do molusco duas gera??es de esporocistos, cerc?rias e metacerc?rias. O hospedeiro definitivo adquire a infec??o por ingest?o do molusco parasitado. O presente estudo teve como objetivos: verificar a a??o do parasito sobre o rim de pombos, Columba livia, atrav?s da an?lise histopatol?gica bem como analisar a morfometria, morfologia e ultraestrutura utilizando a microscopia de luz, eletr?nica de varredura e transmiss?o do ovo, est?gios larvais (mirac?dio, cerc?ria e metacerc?ria) e helminto adulto de P. bragai. Pombos adultos foram obtidos pr?ximos a Central de Abastecimento do Estado do Rio de Janeiro S.A, Iraj?, Munic?pio Rio de Janeiro. Ap?s exame coproparasitol?gico, no laborat?rio, para verifica??o da infec??o, os pombos infectados foram necropsiados para a coleta dos helmintos e do rim infectado. Os pombos n?o infectados foram utilizados como grupo controle. Os protocolos experimentais foram aprovados pela comiss?o de ?tica na pesquisa da UFRRJ. A an?lise histopatol?gica revelou dilata??o dos t?bulos renais, processo inflamat?rio com c?lulas mononucleadas, forma??o de estrutura papiliforme projetando-se para a luz tubular e metaplasia do epit?lio da parede do t?bulo coletor, de epit?lio c?bico simples nos t?bulos n?o infectados a pseudroestratificado nos rins infectados com P. bragai. Os ovos s?o el?pticos, com op?rculo na extremidade anterior e n? na extremidade posterior, regi?o abopercular. A casca apresenta-se ?spera e composta por tr?s camadas: interna, m?dia e externa de espessuras e eletrondensidades diferentes. O mirac?dio ? alongado, com terebratorium na extremidade anterior e corpo coberto por c?lios. As cerc?rias apresentam corpo cil?ndrico que se afunila ligeiramente na regi?o posterior. O tegumento ? rugoso, a ventosa oral ? subterminal, o acet?bulo destaca-se no ter?o m?dio do corpo. Papilas foram verificadas ao redor da ventosa oral. Uma estrutura semelhante ? cauda rudimentar foi observada em algumas cerc?rias. Nas metacerc?rias observadas atrav?s de cortes histol?gicos visualizou-se a ventosa oral, o acet?bulo, as escamas e cisto composto por tr?s camadas, interna, m?dia e externa, de espessuras diferentes. A presen?a das camadas foi confirmada na visualiza??o dos cortes histol?gicos das metacerc?rias na microscopia eletr?nica de varredura. O parasito adulto tem corpo alongado e achatado com ventosa oral, faringe, gl?ndulas vitelog?nicas extracecais que se prolongam anteriormente at? a regi?o de bifurca??o cecal e posteriormente a regi?o mediana do corpo. No poro genital visualiza-se uma estrutura evertida que ? o cirro em formato de roseta. No est?gio adulto o tegumento ? coberto por escamas de v?rios tipos; escamas simples, b?fidas, tr?fidas, com quatro, cinco e sete divis?es, caracter?stica que pode contribuir para ratificar a classifica??o taxon?mica do parasito.
22

Life History Studies of Two Digenetic Trematodes, Bolbophorus Damnificus and an Unknown Clinostomoid Species, that Infect Channel Catfish Ictalurus Punctatus

Doffitt, Cynthia Michelle 09 December 2011 (has links)
The commercial production of channel catfish (Ictalurus punctatus) is major industry in Mississippi. Infections of channel catfish with the digenetic trematode Bolbophorus damnificus have often been associated with heavy economic losses in the industry. To efficiently control transmission of this trematode, the avian hosts need to be identified. In the first study, two American white pelicans, two double-crested cormorants, two great blue herons, and two great egrets were fed channel catfish infected with B. damnificus metacercariae. The presence of Bolbophorus damnificus ova in pelican feces at three days post infection (dpi) indicated the pelicans had patent infections. Mature B. damnificus were recovered from the intestines of both pelicans at 21 dpi. No B. damnificus infections were observed in the other bird species. In a second study, 33 American white pelicans, 34 double-crested cormorants, 35 great blue herons, and 32 great egrets were collected in the Mississippi Delta. The prevalence of B. damnificus in the American white pelican was 93.9%, with an average of 158 B. damnificus found per bird (range 0-681). Bolbophorus damnificus was not found in any of the other bird species. The results of these two studies confirm that the AWPE is the only proven natural host for B. damnificus. In a third study, two previously undescribed cercariae were found infecting rams-horn snails in commercial catfish ponds. In challenge studies, channel catfish were exposed to both cercariae types. Only one type of cercariae (type I) was infective to channel catfish. The first evidence of type I metacercariae was seen histologically at 14 dpi and grossly at 21 dpi. Development continued until 120 dpi, when both gross examination and histology suggested that the metacercariae were mature. The type I metacercariae appeared to cause little host damage. Molecular analysis of the 18S rRNA gene region indicated that the type I cercariae and metacercariae may be a species of Clinostomum. The data generated in these three studies provides additional information that can be used in the development of efficacious management schemes to control digenetic trematodes infecting commercial catfish.
23

Étude parasitologique de Anguilla anguilla dans deux lagunes de Corse et étude ultrastructurale du tégument de trois digènes parasites de cette anguille / parasitological study of Anguilla Anguilla in two lagoons in Corsica and ultrastructural study of the integument of three digeneans parasites that eel

Filippi, Jean-José 14 March 2013 (has links)
Une étude parasitaire de l'anguille d'Europe a été menée dans les lagunes de Biguglia et d'Urbino en Corse. La composition des communautés de parasites a été décrite. Treize espèces parasites ont été identifiées parmi lesquelles: trois digènes, Bucephalus anguillae, Deropristis inflata, Lecithochirium musculus; un monogène, Pseudodactylogyrus anguillae; trois cestodes, Bothriocephalus claviceps, Proteocephalus macrocephalus, Myzophyllobothrium sp. (larve); trois nématodes, Anguillicoloides crassus, Contracaecum sp. (larve enkystée), Goezia anguillae; un acanthocéphale, Acanthocephaloides incrassatus; un copépode, Ergasilus gibbus; et un myxozoaire, Myxobolus portucalensis. La présence d'espèces invasives, notamment le parasite branchial P. anguillae et le nématode parasite A. crassus, dans les lagunes corses est confirmée. Ces espèces, et particulièrement le monogène, présentent des valeurs épidémiologiques croissantes depuis les dernières études menées. Plusieurs espèces présentent des différences de prévalence significatives entre les deux lagunes. Des différences au niveau de la richesse spécifique et des valeurs de diversité, plus élevées pour les parasites des anguilles de la lagune d'Urbino au niveau intestinal métacommunautaire et infracommunautaire, ont été démontrées. Cependant les valeurs les plus élevées de diversité spécifique et les valeurs de dominance les plus basses ont été calculées pour les communautés parasitaires des anguilles de la lagune de Biguglia. Nous avons également mis en avant une diversité parasitaire spécifique plutôt faible chez les anguilles des lagunes corses par rapport aux autres lagunes d'Europe. Les communautés parasitaires de l'anguille d'Europe dans les lagunes de Biguglia et d'Urbino en Corse sont marquées par l'environnement de leur hôte. Une dépendance vis-à-vis de la salinité de la lagune a ainsi été démontrée. Les valeurs d'infestation les plus élevées ont été observées durant les saisons les plus chaudes de l'année pour la majorité des espèces parasites observées (B. anguillae, D. inflata, L. musculus, P. anguillae, P. macrocephalus, A. crassus, les kystes de Contracaecum sp., A. incrassatus et E. gibbus). Nous avons également démontré que l'état d'argenture et la taille ont une influence significative sur les taux d'infestation de sept espèces parasites (D. inflata, L. musculus, P. anguillae, P. macrocephalus, les kystes de Contracaecum sp., A. incrassatus et E. gibbus). La méthode de l'espèce indicatrice a confirmé que le site d'étude, la saison, l'état d'argenture ou la taille de l'anguille pouvait influer sur la présence de certaines espèces parasites. Le tégument de trois digènes parasites de l'anguille d'Europe, B. anguillae, L. musculus et D. inflata, a été étudié en microscopie électronique à balayage et à transmission. Nous avons démontré la présence de structures caractéristiques de l'organisation tégumentaire des digènes ainsi que de formations spécifiques, notamment au niveau de la structure des récepteurs sensoriels et des écailles. / A survey of the parasitic fauna of the European eel has been conducted in the Biguglia and Urbino lagoons in Corsica. The composition of the parasite communities was determined. Thirteen parasite species were identified namely: three digeneans, Bucephalus anguillae, Deropristis inflata, Lecithochirium musculus; one monogenean, Pseudodactylogyrus anguillae; three cestodes, Bothriocephalus claviceps, Proteocephalus macrocephalus, larvae of Myzophyllobothrium sp.; three nematodes, Anguillicoloides crassus, encysted larvae of Contracaecum sp., Goezia anguillae; one acanthocephalan, Acanthocephaloides incrassatus; one copepod, Ergasilus gibbus; and plasmodia of one myxozoan, Myxobolus portucalensis. The presence of invasive species in lagoons from Corsica, namely the gill monogenean P. anguillae and the swimbladder nematode A. crassus, was confirmed. These species, particularly the monogenean, exhibit increasing infection rates since the last studies conducted. Many species showed significant differences in prevalence between the two lagoons. Differences in the species richness and higher values of diversity for the intestinal parasite component communities and infracommunities of eels from the Urbino lagoon were demonstrated. However, highest values of richness and lowest dominance values were observed for the parasite communities of eels from the Biguglia lagoon. We also demonstrated lower values of diversity for the parasite communities of eels from Corsica in comparison to eels from other European lagoons. The environment of the host (in particular the salinity range) has been demonstrated to have a significant influence on the composition of the parasite communities of eels from the Biguglia and Urbino lagoons. Highest values of infestation were observed for the warmer seasons of the year for the majority of the parasite species (B. anguillae, D. inflata, L. musculus, P. anguillae, P. macrocephalus, A. crassus, encysted larvae of Contracaecum sp., A. incrassatus, and E. gibbus). We also demonstrated that silvering stage and length have a significant influence on the rates of infestation by seven parasite species (D. inflata, L. musculus, P. anguillae, P. macrocephalus, cysts of Contracaecum sp., A. incrassatus et E. gibbus). The indicator species method confirmed the assumption that site sampling, season, silvering stage and length of the eel could have an influence on the presence of parasite species. The teguments of three digeneans (B. anguillae, L. musculus and D. inflata) recovered within the European eel were studied using scanning and transmission electron microscopy. We showed the presence of structures characteristic of the tegumental organization of digeneans but also the presence of specific structures such as various types of sensory receptors and spines.
24

Endohelminths from six rare species of turtles (Bataguridae) from Southeast Asia confiscated by international authorities in Hong Kong, China

Murray, Rebecca Ann 30 September 2004 (has links)
Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.
25

Endohelminths from six rare species of turtles (Bataguridae) from Southeast Asia confiscated by international authorities in Hong Kong, China

Murray, Rebecca Ann 30 September 2004 (has links)
Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.

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