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Dissertations / Theses on the topic 'Parasitism'

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Published: 4 June 2021
Last updated: 29 July 2024

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1

Féres, Flávia Corbari [UNESP]. "Ocorrência e caracterização molecular de Cryptosporidium spp. em cordeiros na Região de Araçatuba-SP-Brasil: avaliação da transferência da imunidade passiva." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/92204.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Foram coletadas 460 amostras de fezes de cordeiros com até 30 dias de vida com o objetivo de determinar a ocorrência de Cryptosporidium na região de Araçatuba, assim como as espécies envolvidas nesta parasitose. Realizou-se análise microscópica pela técnica de coloração negativa com verde malaquita em todas as amostras de fezes. Para a identificação molecular de Cryptosporidium, nas amostras positivas à microscopia, utilizou-se a reação de nested PCR, com amplificação de fragmentos da subunidade 18S do gene do RNA ribossômico ou do gene da actina. Encontraram-se 6,73% dos animais eliminando oocistos de Cryptosporidium nas fezes. A espécie e genótipo envolvidos foram: Cryptosporidium parvum e genótipo cervídeo que representam potencial zoonótico e Cryptosporidium parvum tipo B. Foram coletadas também 191 amostras de sangue de cordeiros com até 30 dias de vida com o objetivo de determinar as concentrações séricas de imunoglobulina G, PT, γ globulina, GGT e FA, assim como determinar a associação entre estas variáveis. Foi avaliada se a atividade sérica das enzimas GGT e FA pode ser utilizada indiretamente como indicadora de transferência de imunidade passiva. Para tanto, foram realizados os testes de imunodifusão radial, espectrofotometria e eletroforese respectivamente. Para os valores de GGT e FA, foram utilizados kits comerciais. Houve correlação estatística significativa entre a FA e GGT; fato também observado com relação a PT, a IgG e a GGT. A γ globulina mostrou-se correlacionada com GGT, IgG e PT. A atividade de FA demonstrou-se ineficaz para uso como indicadora de transferência de imunidade passiva.
A total of 460 fecal samples were collected from lambs during the first 30 days of life with the aim to determine the occurrence of Cryptosporidium in Araçatuba region, as well as to identify species involved in this parasitism. Microscopic analysis of feces was carried out using malachite green negative stain. Cryptosporidium positive samples were subjective to a nested PCR, with amplification of fragments of the subunity 18S of the gene of the ribossomic RNA or the gene of the actin. In this study 6.73% of animals were eliminating oocists of Cryptosporidium in their feces. The involved species and genotype were: Cryptosporidium parvum and cervide genotype, which represent a zoonotic potential and Cryptosporidium parvum type B. Blood samples (191) were collected from lambs that were up to 30 days old to determine the serum concentrations of immunoglobulin G, TP, γ globulin, GGT and ALP, as well as to determine the association between these variables. This was done in order to explore the possibility of using changes in activities of GGT e ALP as indirect indicators of immune passive transfer in lambs The following tests were perfomed: radial immunodiffusion, spectrophotometry and electrophoresis respectively. GGT and ALP values were determinate using commercial kits. There was a statistically significant correlation between ALP and GGT. The same correlation was observed from TP, IgG and GGT. A positive γ globulin correlation was found between GGT, IgG and TP. ALP activity cannot be used as an indicator of immune passive transfer.
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2

Reichart, Letitia Marie. "Conspecific brood parasitism in ruddy ducks (Oxyura jamaicensis)." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Summer2008/L_Reichart_072408.pdf.

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3

Féres, Flávia Corbari. "Ocorrência e caracterização molecular de Cryptosporidium spp. em cordeiros na Região de Araçatuba-SP-Brasil : avaliação da transferência da imunidade passiva /." Araçatuba, 2008. http://hdl.handle.net/11449/92204.

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Orientador: Francisco Leydson Formiga Feitosa
Banca: Luiz Cláudio Nogueira Martins
Banca: Maurício Garcia
Resumo: Foram coletadas 460 amostras de fezes de cordeiros com até 30 dias de vida com o objetivo de determinar a ocorrência de Cryptosporidium na região de Araçatuba, assim como as espécies envolvidas nesta parasitose. Realizou-se análise microscópica pela técnica de coloração negativa com verde malaquita em todas as amostras de fezes. Para a identificação molecular de Cryptosporidium, nas amostras positivas à microscopia, utilizou-se a reação de nested PCR, com amplificação de fragmentos da subunidade 18S do gene do RNA ribossômico ou do gene da actina. Encontraram-se 6,73% dos animais eliminando oocistos de Cryptosporidium nas fezes. A espécie e genótipo envolvidos foram: Cryptosporidium parvum e genótipo cervídeo que representam potencial zoonótico e Cryptosporidium parvum tipo B. Foram coletadas também 191 amostras de sangue de cordeiros com até 30 dias de vida com o objetivo de determinar as concentrações séricas de imunoglobulina G, PT, γ globulina, GGT e FA, assim como determinar a associação entre estas variáveis. Foi avaliada se a atividade sérica das enzimas GGT e FA pode ser utilizada indiretamente como indicadora de transferência de imunidade passiva. Para tanto, foram realizados os testes de imunodifusão radial, espectrofotometria e eletroforese respectivamente. Para os valores de GGT e FA, foram utilizados kits comerciais. Houve correlação estatística significativa entre a FA e GGT; fato também observado com relação a PT, a IgG e a GGT. A γ globulina mostrou-se correlacionada com GGT, IgG e PT. A atividade de FA demonstrou-se ineficaz para uso como indicadora de transferência de imunidade passiva.
Abstract: A total of 460 fecal samples were collected from lambs during the first 30 days of life with the aim to determine the occurrence of Cryptosporidium in Araçatuba region, as well as to identify species involved in this parasitism. Microscopic analysis of feces was carried out using malachite green negative stain. Cryptosporidium positive samples were subjective to a nested PCR, with amplification of fragments of the subunity 18S of the gene of the ribossomic RNA or the gene of the actin. In this study 6.73% of animals were eliminating oocists of Cryptosporidium in their feces. The involved species and genotype were: Cryptosporidium parvum and cervide genotype, which represent a zoonotic potential and Cryptosporidium parvum type B. Blood samples (191) were collected from lambs that were up to 30 days old to determine the serum concentrations of immunoglobulin G, TP, γ globulin, GGT and ALP, as well as to determine the association between these variables. This was done in order to explore the possibility of using changes in activities of GGT e ALP as indirect indicators of immune passive transfer in lambs The following tests were perfomed: radial immunodiffusion, spectrophotometry and electrophoresis respectively. GGT and ALP values were determinate using commercial kits. There was a statistically significant correlation between ALP and GGT. The same correlation was observed from TP, IgG and GGT. A positive γ globulin correlation was found between GGT, IgG and TP. ALP activity cannot be used as an indicator of immune passive transfer.
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4

Soutello, Ricardo Velludo Gomes de [UNESP]. "Influência do parasitismo e da suplementação no desenvolvimento ponderal de novilhos mestiços Angus-Nelore e da raça Guzerá." Universidade Estadual Paulista (UNESP), 2001. http://hdl.handle.net/11449/98643.

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Analisou-se os efeitos do tratamento anti-helmíntico estratégico e da suplementação protéica no ganho de peso de novilhos, do desmame até o abate. Foram utilizados 40 animais, com 8-9 meses de idade, 20 da raça Guzerá e 20 mestiços (Nelore - Angus), pesando em média 211,8 Kg. Esses animais foram distribuídos em quatro lotes, conforme o peso e permaneceram em quatro piquetes de aproximadamente 10 hectares cada, formado por Brachiaria decumbens. Dois lotes, grupos 1 e 2, receberam suplementação protéica comercial com 50 % de proteína bruta durante a seca e com 15 % durante as águas, fornecido ad libitum, e dois receberam somente mistura mineral, grupos 3 e 4 (controle). Dos lotes que receberam suplementação, apenas um foi tratado com endectocida Moxidectin 1% (grupo 1), o mesmo ocorrendo para os que receberam a mistura mineral (grupo 3). A cada 28 dias, os animais foram pesados e suas fezes colhidas para a contagem de ovos por grama de fezes (OPG) e coprocultura, e a cada 14 dias foi feito contagem de carrapatos de um lado do animal. O ganho de peso dos animais dos grupos um, dois, três e quatro foram de: 0,453 Kg, 0,320 Kg, 0,339 Kg e 0,231 Kg, por dia, respectivamente. Observou-se uma diferença significativa de peso entre os animais suplementados e tratados (grupo 1) em relação aos animais apenas tratados (grupo 3) e apenas suplementados (grupo 2), que por sua vez também foram significativamente diferentes dos animais que não receberam tratamento nem suplementação (grupo 4). A média de OPG nos grupos um, dois, três e quatro foi de: 19,82; 275,98; 31,34 e 254,55 respectivamente, com diferença significativa entre os animais tratados com anti-helmíntico (grupos 1 e 3) e os não tratados (grupos 2 e 4). As contagens médias de carrapatos nos grupos um, dois, três e quatro foram de: 1,2; 7,7; 0,8 e 9,3 respectivamente, com diferença... .
The effect of strategic anthelmintic treatment and protein suplementation was evaluated in steers using the weight gain as a parameter, during the period from weans to slawghtery. Forty animals were used, with 8-9 months of age, 20 of Guzera breed (Bos indicus) and 20 Nelore - Angus, weighing 211.8 kg in average. These animals were distributed in four groups and remained in four paddoks of 10 hectares each, formed by Brachiaria decumbens. Two groups had received commercial protein suplement with 50% of crude protein during the dry period and with 15% of crude protein, during the wet period, supplied ad libitum (groups 1 and 2) and the others two received only mineral mixture; groups 3 and 4 (control group). From those animals that received protein suplement, only one was treated with anthelmintic 1% Moxidectin (group 1), the same occurring for those animals that received mineral mixture (group 3). At 28 days of intervals the animals were weighed and theirs fecal samples were collected for nematode egg counts (EPG) and larval cultures, and at 14 days of intervals ticks were counted on a half of animal. The weight gain in group 1, 2, 3 and 4 was: 0.453 kg, 0.320 kg, 0.339 kg and 0,231 kg per day, respectively. Statistical significace of weight gain occurred between the animals supplemented and medicated (group 1) in relation to the animals that were only medicated (group 3) or betweem the groups that were only supplemented (group 2), and no medicated and suplemented (group 4). The average of EPG in groups 1, 2, 3 and 4 was of: 19.82; 275.98; 31.34 and 254.55 respectively, with significant difference in the animals medicated with anthelmintic (groups 1 and 3) and no medicated (groups 2 and 4). The tick counts in groups 1, 2, 3 and 4 was of: 1,2; 7,7; 0,8 e 9,3 respectively, with significant difference in the animals medicated (groups 1 and 3) and no... (Complete abstract, click electronic address below).
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5

Naranjo, Guevara Natalia [UNESP]. "Bioecologia comparada de duas linhagens de Telenomus remus Nixon (Hymenoptera: Platygastridae) parasitando ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/91324.

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A criação massal em condições de laboratório afeta a atividade e vigor dos parasitoides e,consequentemente, opotential como agentes de controle biológico. No Brasil, Telenomus remus foi introduzido em1986 e obtiveram-se altos níveis de parasitismo sobre Spodoptera frugiperda em testes de laboratório. Entretanto, estes níveis não foram obtidos em condições de campo.Assim, para ampliar abasegenéticadas linhagens e determinar possíveisdiferenças naatividade e vigor, opresente estudo objetivou: (1) realizara introdução deuma nova linhagem de T. remus no Brasil, a partir da Venezuela; (2) comparar a biologia das duas linhagens (uma coletada em culturas de milho e introduzida e outra,criadapor cerca de 600 gerações em laboratório) por meio da avaliaçãode parâmetros reprodutivos etabela de vida de fecundidade; (3) comparar as respostas funcionais; (4) avaliar a qualidade das linhagens utilizando-se a atividadede voo e a emergência como critérios. A espécie foi confirmada por taxonomista e foi confirmadaa sua especificidade porS. frugiperda. As duas linhagens demostraram similaridade genética em padrõesde restrição para asregiões 16S e ITS1, embora a linhagem importada apresentasse qualidadesuperior. Osparâmetros de fecundidadedemostraram que alinhagem introduzida temum potencial de aumento populacional maior e éintrinsecamente mais agressiva. As duas linhagens apresentaram resposta funcional tipo III, comestabilizaçãodo parasitismo apartirde 200 ovosdohospedeiro. Infere-se que a criaçãoem laboratório de T. remus requer cuidados que limitem a perda do potencial para controle biológico. Avaliaçõessubsequentes de qualidade bem como ametodologia atual de criação precisam ser revistas.O presente estudo resultou numimportante aporte para auxiliar na implementação de programas de controle biológico para a lagarta-do-cartucho.
Mass rearing in laboratory conditions affects the activity and vigor of parasitoids and consequentlytheir potentialas biological agents. In Brazil, Telenomus remus was introduced in 1986 and high levels of parasitism on Spodoptera frugiperda were obtained in laboratory tests. However, theselevels were notobtained infield conditions. Thus, tobroaden thegeneticbases of laboratorymaintained strains and to determine possible differencesin activity and vigor, this study aimed to:(1) introduce a new strain ofT. remus from Venezuela in Brazil;(2) compare the biology of two strains of T.remus (one collected in maizefields and introduced, and the other, maintained by over 600generations in laboratory conditions) by evaluatingreproductive parameters and fertilitylife tables, (3)compare the functional responses; (4) evaluate thequality ofthestrains using flightacitivity and emergence as criteria. The introduced species was confirmed by a taxonomist and their specificity for S. frugiperda was confirmed.Both strains demonstrated genetic similarity in restriction patterns for the 16S and ITS1 regions, although the imported strain showed superior quality as biological control agent. The fertility parameters showed thattheintroduced strain has a greater potentialfor population increaseand is inherently more aggressive. The two strains exhibited type IIIfunctional response, with stabilization of parasitism at 200 hosteggs. It is inferred that the laboratory rearingof T. remus requires efforts toprevent lossof biological control potential. Further evaluations of quality must be made and the currentmass rearing methodology should bere-designed. This study resulted in an important contribution that could aid the implementation of biological control programs for fall armyworm.
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6

Aguiar, Aline [UNESP]. "Helmintofauna associativa à anfíbios da Ilha Anchieta, litoral norte do estado de São Paulo, Brasil." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/108606.

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Os anfíbios ocupam grande variedade de microhabitats refletindo os diversos modos reprodutivos, estilos de vida e parasitas que estes animais apresentam. Os parasitas são indicativos de muitos aspectos biológicos de seus hospedeiros, incluindo a dieta, ocupação do habitat e a filogenia, podendo também ser bons indicadores diretos do estado de qualidade ambiental. A Ilha Anchieta, parque estadual em área de Mata Atlântica, torna-se interessante para estudos biológicos devido a sua dinâmica insular e isolamento geográfico. O objetivo deste estudo foi avaliar a fauna de helmintos de 195 anfíbios da Ilha Anchieta representados por 14 espécies, Flectonotus fissilis (n = 18), Haddadus binotatus (n = 9), Ischnocnema bolbodactyla (n = 4), Ischnocnema parva (n = 20), Rhinella ornata (n = 20), Dendrophryniscus brevipollicatus (n = 3), Hypsiboas albomarginatus (n = 18), Scinax hayii (n = 23), Hylodes asper (n = 2), Hylodes phyllodes (n = 3), Leptodactylus cf. marmoratus (n = 42), Leptodactylus latrans (n = 4), Chiasmocleis carvalhoi (n = 26) e Myersiella microps (n = 3). Foram identificadas pelo menos 14 espécies de helmintos entre as comunidades componentes dos anfíbios: 12 espécies de nematóides (Falcaustra mascula, Oxyascaris oxyascaris, Oswaldocruzia sp., Rhabdias sp., Physaloptera sp., Aplectana crucifer, Aplectana pintoi, Aplectana sp., Cosmocerca brasiliense, Cosmocerca parva, Cosmocerca travassosi e Cosmocerca sp.), uma espécie de cestóide (Cylindrotaenia cf. americana) e uma espécie de Acanthocephala (cistacantos). Este estudo apresenta uma revisão dessas espécies de helmintos com seus anfíbios hospedeiros até hoje relatados; a helmintofauna associada a estas espécies hospedeiras; e uma análise de similaridade das infracomunidades de algumas espécies de anfíbios, mostrando que o habitat pode influenciar na composição e abundância da comunidade parasita
The amphibians use a variety of microhabitats, relationship with the various reproductive modes, life style and parasites that these animals presented. The parasites are indicatives about a lot of biological aspects of yours hosts, including feeding, use of habitat and phylogeny. They also may be good indicators about status of environmental quality. The Anchieta Island, state park in Atlantic Rain Forest area, is very interesting for biological studies because insular dynamics and geographical isolation. The aim of this study was to evaluate the helminth fauna of 195 amphibians from Anchieta Island representing 14 species, Flectonotus fissilis (n = 18), Haddadus binotatus (n = 9), Ischnocnema bolbodactyla (n = 4), Ischnocnema parva (n = 20), Rhinella ornata (n = 20), Dendrophryniscus brevipollicatus (n = 3), Hypsiboas albomarginatus (n = 18), Scinax hayii (n = 23), Hylodes asper (n = 2), Hylodes phyllodes (n = 3), Leptodactylus cf. marmoratus (n = 42), Leptodactylus latrans (n = 4), Chiasmocleis carvalhoi (n = 26), and Myersiella microps (n = 3). They were necropsied to examine for helminth parasites. We identified at least 14 helminths species in the component communities of anurans: 12 nematodes species (Falcaustra mascula, Oxyascaris oxyascaris, Oswaldocruzia sp., Rhabdias sp., Physaloptera sp., Aplectana crucifer, Aplectana pintoi, Aplectana sp., Cosmocerca brasiliense, Cosmocerca parva, Cosmocerca travassosi, and Cosmocerca sp.), one cestode species (Cylindrotaenia cf. americana), and one species of Acanthocephala (cystacanths). This study presents a revision about these helminth species with the related hosts to date; the helminth fauna associated to these host species; and the similarity about infracommunities of some amphibian species, showing habitat can influence on composition and abundance of parasite community
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Aguiar, Aline. "Helmintofauna associativa à anfíbios da Ilha Anchieta, litoral norte do estado de São Paulo, Brasil /." Botucatu, 2013. http://hdl.handle.net/11449/108606.

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Orientador: Reinaldo José da Silva
Coorientador: Luciano Alves dos Anjos
Banca: Max Rondon Werneck
Banca: Vanda Lucia Ferreira
Resumo: Os anfíbios ocupam grande variedade de microhabitats refletindo os diversos modos reprodutivos, estilos de vida e parasitas que estes animais apresentam. Os parasitas são indicativos de muitos aspectos biológicos de seus hospedeiros, incluindo a dieta, ocupação do habitat e a filogenia, podendo também ser bons indicadores diretos do estado de qualidade ambiental. A Ilha Anchieta, parque estadual em área de Mata Atlântica, torna-se interessante para estudos biológicos devido a sua dinâmica insular e isolamento geográfico. O objetivo deste estudo foi avaliar a fauna de helmintos de 195 anfíbios da Ilha Anchieta representados por 14 espécies, Flectonotus fissilis (n = 18), Haddadus binotatus (n = 9), Ischnocnema bolbodactyla (n = 4), Ischnocnema parva (n = 20), Rhinella ornata (n = 20), Dendrophryniscus brevipollicatus (n = 3), Hypsiboas albomarginatus (n = 18), Scinax hayii (n = 23), Hylodes asper (n = 2), Hylodes phyllodes (n = 3), Leptodactylus cf. marmoratus (n = 42), Leptodactylus latrans (n = 4), Chiasmocleis carvalhoi (n = 26) e Myersiella microps (n = 3). Foram identificadas pelo menos 14 espécies de helmintos entre as comunidades componentes dos anfíbios: 12 espécies de nematóides (Falcaustra mascula, Oxyascaris oxyascaris, Oswaldocruzia sp., Rhabdias sp., Physaloptera sp., Aplectana crucifer, Aplectana pintoi, Aplectana sp., Cosmocerca brasiliense, Cosmocerca parva, Cosmocerca travassosi e Cosmocerca sp.), uma espécie de cestóide (Cylindrotaenia cf. americana) e uma espécie de Acanthocephala (cistacantos). Este estudo apresenta uma revisão dessas espécies de helmintos com seus anfíbios hospedeiros até hoje relatados; a helmintofauna associada a estas espécies hospedeiras; e uma análise de similaridade das infracomunidades de algumas espécies de anfíbios, mostrando que o habitat pode influenciar na composição e abundância da comunidade parasita
Abstract: The amphibians use a variety of microhabitats, relationship with the various reproductive modes, life style and parasites that these animals presented. The parasites are indicatives about a lot of biological aspects of yours hosts, including feeding, use of habitat and phylogeny. They also may be good indicators about status of environmental quality. The Anchieta Island, state park in Atlantic Rain Forest area, is very interesting for biological studies because insular dynamics and geographical isolation. The aim of this study was to evaluate the helminth fauna of 195 amphibians from Anchieta Island representing 14 species, Flectonotus fissilis (n = 18), Haddadus binotatus (n = 9), Ischnocnema bolbodactyla (n = 4), Ischnocnema parva (n = 20), Rhinella ornata (n = 20), Dendrophryniscus brevipollicatus (n = 3), Hypsiboas albomarginatus (n = 18), Scinax hayii (n = 23), Hylodes asper (n = 2), Hylodes phyllodes (n = 3), Leptodactylus cf. marmoratus (n = 42), Leptodactylus latrans (n = 4), Chiasmocleis carvalhoi (n = 26), and Myersiella microps (n = 3). They were necropsied to examine for helminth parasites. We identified at least 14 helminths species in the component communities of anurans: 12 nematodes species (Falcaustra mascula, Oxyascaris oxyascaris, Oswaldocruzia sp., Rhabdias sp., Physaloptera sp., Aplectana crucifer, Aplectana pintoi, Aplectana sp., Cosmocerca brasiliense, Cosmocerca parva, Cosmocerca travassosi, and Cosmocerca sp.), one cestode species (Cylindrotaenia cf. americana), and one species of Acanthocephala (cystacanths). This study presents a revision about these helminth species with the related hosts to date; the helminth fauna associated to these host species; and the similarity about infracommunities of some amphibian species, showing habitat can influence on composition and abundance of parasite community
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8

Naranjo, Guevara Natalia. "Bioecologia comparada de duas linhagens de Telenomus remus Nixon (Hymenoptera: Platygastridae) parasitando ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) /." Jaboticabal, 2013. http://hdl.handle.net/11449/91324.

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Orientador: Odair Aparecido Fernandes
Banca: Marta Maria Rossi
Banca: Nelson Wanderley Perioto
Resumo: A criação massal em condições de laboratório afeta a atividade e vigor dos parasitoides e,consequentemente, opotential como agentes de controle biológico. No Brasil, Telenomus remus foi introduzido em1986 e obtiveram-se altos níveis de parasitismo sobre Spodoptera frugiperda em testes de laboratório. Entretanto, estes níveis não foram obtidos em condições de campo.Assim, para ampliar abasegenéticadas linhagens e determinar possíveisdiferenças naatividade e vigor, opresente estudo objetivou: (1) realizara introdução deuma nova linhagem de T. remus no Brasil, a partir da Venezuela; (2) comparar a biologia das duas linhagens (uma coletada em culturas de milho e introduzida e outra,criadapor cerca de 600 gerações em laboratório) por meio da avaliaçãode parâmetros reprodutivos etabela de vida de fecundidade; (3) comparar as respostas funcionais; (4) avaliar a qualidade das linhagens utilizando-se a atividadede voo e a emergência como critérios. A espécie foi confirmada por taxonomista e foi confirmadaa sua especificidade porS. frugiperda. As duas linhagens demostraram similaridade genética em padrõesde restrição para asregiões 16S e ITS1, embora a linhagem importada apresentasse qualidadesuperior. Osparâmetros de fecundidadedemostraram que alinhagem introduzida temum potencial de aumento populacional maior e éintrinsecamente mais agressiva. As duas linhagens apresentaram resposta funcional tipo III, comestabilizaçãodo parasitismo apartirde 200 ovosdohospedeiro. Infere-se que a criaçãoem laboratório de T. remus requer cuidados que limitem a perda do potencial para controle biológico. Avaliaçõessubsequentes de qualidade bem como ametodologia atual de criação precisam ser revistas.O presente estudo resultou numimportante aporte para auxiliar na implementação de programas de controle biológico para a lagarta-do-cartucho.
Abstract: Mass rearing in laboratory conditions affects the activity and vigor of parasitoids and consequentlytheir potentialas biological agents. In Brazil, Telenomus remus was introduced in 1986 and high levels of parasitism on Spodoptera frugiperda were obtained in laboratory tests. However, theselevels were notobtained infield conditions. Thus, tobroaden thegeneticbases of laboratorymaintained strains and to determine possible differencesin activity and vigor, this study aimed to:(1) introduce a new strain ofT. remus from Venezuela in Brazil;(2) compare the biology of two strains of T.remus (one collected in maizefields and introduced, and the other, maintained by over 600generations in laboratory conditions) by evaluatingreproductive parameters and fertilitylife tables, (3)compare the functional responses; (4) evaluate thequality ofthestrains using flightacitivity and emergence as criteria. The introduced species was confirmed by a taxonomist and their specificity for S. frugiperda was confirmed.Both strains demonstrated genetic similarity in restriction patterns for the 16S and ITS1 regions, although the imported strain showed superior quality as biological control agent. The fertility parameters showed thattheintroduced strain has a greater potentialfor population increaseand is inherently more aggressive. The two strains exhibited type IIIfunctional response, with stabilization of parasitism at 200 hosteggs. It is inferred that the laboratory rearingof T. remus requires efforts toprevent lossof biological control potential. Further evaluations of quality must be made and the currentmass rearing methodology should bere-designed. This study resulted in an important contribution that could aid the implementation of biological control programs for fall armyworm.
Mestre
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9

Léonard, Nancy Jacynthe. "Ectoparasitism of odonate hosts, host response to parasitism and host sex bias in parasitism." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36940.pdf.

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10

Nair, Radha Goh. "Neural adaptations for brood parasitism." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409117.

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11

Normanton, Heidi. "The nutritional control of parasitism." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/2566.

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Expression of acquired immunity to gastrointestinal parasites usually breaks down during the periparturient period, which is characterised by an increased worm burden and nematode egg excretion. It is believed that this breakdown of immunity may have a nutritional basis, and that by reducing nutrient scarcity the lactating animal will be able to reduce her worm burden. Therefore, the aim of this thesis was to carry out four experiments to investigate the potential use of metabolisable protein as an alternative way to control gastrointestinal parasitism in periparturient animals. A lactating rat model was used to address this issue as lactating rats exhibit a breakdown of immunity to the gastrointestinal nematode Nippostrongylus brasiliensis. The first experiment (chapter two) aimed to verify that a reduction in worm burden is indeed related to changes in nutrient supply and not associated with changes in the gut environment. This was achieved by manipulating nutrient (litter) demand whilst nutrient supply was maintained constant. The results showed that the periparturient breakdown of immunity to N. brasiliensis (measured by a reduced worm burden) was sensitive to changes in nutrient demand and that these effects were independent of changes in the gut environment. The second experiment (Chapter Three) tested the effect of increased protein supply or reduced protein demand on the resistance to parasites in lactating rats whilst energy intake was kept constant. Under these conditions effects of protein supply could not be confounded with effects of any nutrient or energy intake. The results supported the view that under a restricted feeding regime, breakdown of immunity to N. brasiliensis (measured by a reduced number of eggs in the colon content) was sensitive to changes in protein scarcity. Following on from this, the next experiment (Chapter Four) assessed the effects of a gradual increase in protein supply on resistance and immune responses to N. brasiliensis in lactating rats. It was shown that as protein contents of the diets progressively increased, the number of worms and eggs present in the colon decreased. Although we found that differences in protein supply affected parasite burden, we found no affects of protein supply on local immune responses. This may have been due to the single sampling point used. Therefore, the objective of the last experiment (Chapter Five) was to assess temporal effects of increased protein supply on resistance and immune responses to N. brasiliensis. In agreement with previous experiments, the results showed that an increase in protein at times of protein scarcity improved resistance to N. brasiliensis, illustrated by a lower number of nematode eggs in the colon. The results also showed that local immune responses such as immunoglobulin levels (IgA, IgE & IgG2a), RMCP II levels and goblet cell counts were affected by differences in protein supply at various time points post secondary infection. The potential application of using a lactating rat as a suitable model to fully understand the underlying immunological basis of relaxation in immunity during the periparturient period and its sensitivity to nutrient scarcity is considered in the General Discussion (Chapter Six).
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Gloag, Rosalyn Suzanne. "Brood parasitism by shiny cowbirds." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:b9a9d900-ed14-4bb0-8979-7fd782584f00.

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Brood parasitic birds lay eggs amongst the clutches of other species, which then assume all costs of parental care on their behalf. This thesis addresses several puzzles of avian brood parasitism, using field studies and theoretical modelling of the generalist parasite, the shiny cowbird (Molothrus bonariensis) and select hosts in Argentina. Key findings and conclusions were: • High parasitism intensity in a host population can result in a cost to hosts of removing parasite eggs from their clutches, and so help to maintain host’s acceptance of parasite eggs in evolutionary equilibrium. The cost is to host egg survival: hosts that remove parasite eggs from the clutch increase the risk that their eggs are destroyed by subsequent parasites that visit the nest. • The principal benefit of mobbing as a front-line defence of hosts may be to reduce egg loss due to parasite attack, rather than prevent parasitism itself. • Differences in the acoustic structure of begging calls between parasites and their host’s young can be to the parasite’s advantage. Parents provisioned unparasitized broods more during broadcast at the nest of shiny cowbird calls than calls of their own species’ chicks, in both a common host and a non-host. The long tremulous quality of a cowbird’s call functions analogously to a rapid call rate, thereby exploiting a common provisioning rule of avian parents. • A trade-off for maximum growth in parasite nestlings will variously favour or not favour the evolution of nestmate-killing behaviour, depending on a parasite’s abilities, relative to host young, to solicit and attain provisions from host parents. Generalist parasites can encounter both sides of the trade-off in different hosts. Meanwhile, indirect fitness costs are unlikely to constrain the evolution of nestmate-killing in shiny cowbirds, as they rarely, if ever, share the nest with siblings.
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Hillegass, Melissa Ann. "SEX-BIASED PARASITISM AND THE REPRODUCTIVE COSTS OF PARASITES IN A SOCIAL AFRICAN GROUND SQUIRREL." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2205.

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Vertebrate males frequently carry higher numbers of parasites than females. This bias in parasite loads could be a consequence of sexual selection. Grouping species are also assumed to be afflicted with larger numbers of parasites than solitary animals and associated costs of this parasitism could vary with group size or structure. I examined sex-biased parasitism and the influence of group size on parasite loads in Cape ground squirrels (Xerus inauris), a highly social species that occurs in the arid regions of southern Africa. Males carried three times as many ectoparasites as females, but females harbored nearly three times more endoparasites than males. Amount of time spent (per hour) autogrooming was similar between males and females, but amount time spent allogrooming by adult female was over eleven times that of adult males. Longer allogrooming of group members could be decreasing the numbers of ectoparasites of group members and ultimately the group. Males infrequently give or receive allogrooming and travel in very large home ranges, potentially increasing their exposure to ectoparasites. However, movement throughout a large home range may result in males foraging in areas with lower densities of fecal pellets, which could explain the lower endoparasite loads observed in males. When I considered the age class of group members, female age classes were similarly parasitized but male age classes were not. Sub-adult males carried similar ectoparasite loads to adult males and similar endoparasite loads to adult females. This result is of particular interest because sub-adult males are becoming scrotal but typically remain in the group until adulthood. Sexual selection does appear to influence parasite loads in this species, and parasite removal or avoidance potentially mitigates individual parasite loads and their associated costs. Parasites can be detrimental to the health, longevity, and reproduction of their hosts, but these costs are rarely quantified. I removed ectoparasites and endoparasites from Cape ground squirrels for three months and evaluated changes in female body mass, reproduction, burrow use, and grooming in response to parasite removal. Female body mass did not increase with parasite removal, but reproductive success (per capita offspring raised to emergence) increased nearly four-fold, while allogrooming by treated females decreased. Since breeding is highest in the late winter dry season when fewer resources are available, the impact of parasites may be highest during this season. Lactation and gestation are the most physiological stressful processes that females undergo, and the dramatic increase in reproductive success in treated females suggests that these females are able to allocate more resources to reproduction than females afflicted with parasites. These results suggest that studies investigating reproduction and fecundity must consider the vulnerability of the host to parasite infection and the potential impact on reproductive success.
M.S.
Department of Biology
Sciences
Biology MS
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14

Mueller-Graf, Christine D. M. "Ecological parasitism of baboons and lions." Thesis, University of Oxford, 1994. https://ora.ox.ac.uk/objects/uuid:ffd4ddb0-fbef-4be8-803f-cb3578f7e7e0.

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This thesis investigates the epidemiology of intestinal parasites in wild populations of two social animals, olive baboons (Papio anubis) in Gombe Stream National Park, Tanzania, East-Africa, and lions (Panthera leo) in the Serengeti and Ngorongoro-Crater, Tanzania. These populations have been observed for over 20 years and detailed information on individual hosts was available for analysis with the parasitological data allowing to address questions about the relationship of host genetics and social behaviour to parasite infection. The baboons were infected with seven different helminths as well as two types of protozoans. Fifteen morphologically different parasites were found in the lions. All baboons and almost all lions were parasitized. Parasite distribution in both host species was overdispersed. Spatial differences in parasite infection in the baboons and lions emerged as the strongest effect on heterogeneity of infection. Parasites of both host species showed seasonal and temporal variation. Parasite-parasite associations did not appear to have a strong impact on overall patterns of infection in either baboons or lions. Across all parasite taxa, age (with one exception in baboons), sex, reproductive status and group size had little significant influence on parasite burden. For baboons age-prevalence and age-severity profiles resembled those for the same parasites in humans. Correlations between baboon social rank and parasite burden were equivocal. Parasite infection was not correlated with size of baboon female genital swelling. Two lion populations were compared, an inbred and an outbred. Only one parasite, Spirometra spp., had a significantly higher prevalence in the inbred population, contrary to expectations. Results of this study suggest that any effects on levels of infection in these wild populations due to social behaviour, genetics, sex and reproductive effort may be masked by the stronger influence of environmental and/or behavioural components of exposure, at least in the short term. This implies that the importance of factors such as genetics or social behaviour on infection may not always be apparent and may be dependent on the details of the local ecology of both host and parasite at the time the system is studied.
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Daversa, David Robert. "Movement and parasitism in fragmented habitats." Thesis, University of Cambridge, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709508.

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Ma, Hansong. "Intracellular parasitism of macrophages by Cryptococcus." Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/465/.

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The pathogenic fungi Cryptococcus neoformans and Cryptococcus gattii are two of the main causes of life-threatening meningoencephalitis in immunocompromised and immunocompetent individuals respectively. Following inhalation, cryptococci are engulfed by phagocytic cells in the lung and previous studies by our group and others have demonstrated that they are then able to survive inside these cells (especially macrophages), thus acting as intracellular parasites. This intracellular phase is thought to underlie the ability of the pathogens to remain latent for long periods of time within infected individuals. Here, we demonstrate that cryptococci can also manipulate host macrophages in order to mediate an exquisitely controlled ‘escape’ process. This expulsive process, which we have termed ‘vomocytosis’, can occur either into the extracellular milieu or, remarkably, into neighbouring host cells, thus resulting in direct cell-to-cell transmission (‘lateral transfer’). After vomocytosis, both the host macrophages and the expelled cryptococci appear morphologically normal and continue to proliferate. Vomocytosis therefore represents an important mechanism by which pathogens are able to escape from phagocytic cells without triggering host cell death and thus inflammation. Moreover, direct cell-to-cell spread of cryptococci allows the pathogen to remain concealed from the immune system and protected from antifungal agents, thus achieving long-term latency. This project has also provided a possible explanation for the molecular cause of a recent C. gattii outbreak on Vancouver Island, Canada. We found that isolates from the outbreak have dramatically increased their ability to replicate within macrophages in comparison with other C. gattii strains, despite the fact that they are genetically very similar to each other. We further demonstrate that such enhanced intracellular parasitism is directly linked to virulence in a murine model of cryptococcosis, suggesting that this ability might be the cause of the outbreak. Finally, application of high-density whole genome tiled arrays, confocal microscopy and mating assays reveal regulation of mitochondrial activity to be a major driver of virulence in this pathogen group. Taken together, these data indicate that a recent change in mitochondrial regulation within the C. gattii lineage has led to an increased intracellular proliferative capacity, resulting in the hypervirulent phenotype that underlies the outbreak. Such shifts in intracellular replication capacity may be a widespread phenomenon in other human pathogens and could potentially underpin disease epidemics caused by otherwise unrelated pathogens.
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Granroth-Wilding, Hanna Maria Veronica. "Parasitism, family conflict and breeding success." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8243.

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Parasites are important drivers of ecological and evolutionary processes in their hosts. However, hosts often differ in how they are affected by parasitism, which can be important in how parasite effects on individuals scale up to the population level. Hosts may differ intrinsically in their susceptibility to parasitism, and extrinsic factors may impose constraints on how hosts allocate resources between immunity, maintenance and reproduction, thereby further affecting their ability to cope with infection. These extrinsic factors include the host’s ecological environment, for example food availability or weather, and its social environment, that is its interactions with conspecifics. This is particularly true during a reproductive attempt when individuals interact closely with other family members. Not only might immediate impacts of parasitism differ between and within parents and offspring, but the direct effects of parasitism on a host could have further indirect consequences for other family members through their behavioural interactions with parasitised individuals. The distribution of direct and indirect effects among all family members could affect the outcome of the breeding event and individuals’ future performance. However, teasing apart these various avenues of parasite impacts on families may be difficult if parasite burden or susceptibility is correlated between family members. In this thesis, I explore the consequences of parasitism for different family members of the European shag Phalacrocorax aristotelis infected with gastrointestinal nematodes, over a range of ecological conditions. In chapter 2, I demonstrate that chicks’ responses to anti-parasite treatment across four years vary between siblings and with environmental conditions, which may be mediated by resource allocation among siblings. In chapter 3, I explore how costs of parasitism are distributed among the whole family by simultaneously treating chicks and/or parents with an anti-parasite drug and measuring the outcomes for all family members. Treatment has a more marked effect for the non-treated generation than for the treated individuals, suggesting that parasitism may have important indirect costs. In chapter 4, I investigate whether within-brood variability in the effects of anti-parasite treatment and its cross-generational impacts are mediated by behavioural change, and show that chick treatment but not parent treatment influences several aspects of behaviour in the nest. In chapter 5, I demonstrate that the impact of chick anti-parasite treatment on parents persists beyond the breeding attempt, with parents of treated chicks foraging less overwinter and breeding earlier the following year, whereas there is no persistent effect of parents’ own anti-parasite treatment. Lastly, I provide an appendix examining the parasitology of the system in detail, including an assessment of in situ and proxy measures of worm burdens of chicks. This thesis demonstrates that parasitism can be a key component, previously overlooked, of reproductive performance in seabirds, a group that plays an important ecological role as apex predators and thus indicator species of the marine environment.
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Poirotte, Clémence. "Stratégies d’évitement parasitaire chez une population de primates sociaux en milieu naturel." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT166.

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Les pressions de sélection exercées par les parasites ont permis l’évolution de mécanismes complexes de défense chez les espèces hôtes qui limitent la transmission parasitaire. En complément de leur système immunitaire physiologique, les animaux ont développé un « système immunitaire comportemental » comprenant un ensemble sophistiqué de stratégies d’évitement parasitaire représentant une première ligne de défense pour diminuer la probabilité de rencontre avec différents parasites. Cependant, ces stratégies comportementales n’ont été que peu étudiées chez les espèces de mammifères vivant en milieu naturel. Au cours de ma thèse, j’ai donc étudié les stratégies d’évitement parasitaire dans une population sauvage de mandrills (Mandrillus sphinx), un primate de l’Ancien Monde vivant dans les forêts denses équatoriales d’Afrique et soumis à de forces pressions parasitaires. Je me suis en particulier intéressée aux différentes stratégies comportementales qui ont évolué en réponse au risque de contamination par deux types distincts de parasites gastro-intestinaux présentant des traits d’histoire de vie et des modes de transmission contrastés : les nématodes, transmis par l’environnement, et les protozoaires, transmis par contacts sociaux. A partir d’observations récoltées sur le long-terme, de test expérimentaux et d’analyses chimiques, mes études ont mis en évidence deux stratégies comportementales différentes, soulignant le lien étroit entre l’écologie des parasites et la réponse comportementale des hôtes. D’une part, les mandrills évitent les matières fécales lorsqu’ils fourragent et évitent également les habitats précédemment contaminés par des nématodes fécaux émis lors de la dernière visite de ces habitats. D’autre part, les mandrills évitent de toiletter leurs partenaires sociaux parasités par des protozoaires fécaux, particulièrement autour de la zone anale. Cette stratégie comportementale s’avère être efficace puisque les individus parasités présentent des kystes infectieux de protozoaires sur leurs corps, concentrés au niveau de la zone anale, et la richesse en protozoaire des individus augmente lorsqu’ils toilettent des congénères très parasités. De plus, nous avons montré que cet évitement des individus parasités était guidé par un mécanisme olfactif : les protozoaires influencent l’odeur des matières fécales et les individus discriminent et évitent l’odeur des matières fécales provenant d’individus parasités. Cette plasticité comportementale face au risque parasitaire pourrait constituer un des mécanismes majeurs permettant aux espèces sociales de diminuer le risque accru de contamination associé à la vie en groupe. L’ensemble de nos résultats permettent de mieux appréhender les conséquences évolutives des pressions de sélection exercées par les parasites sur différentes caractéristiques socio-écologiques des animaux, tels que l’utilisation de l’espace et les comportements sociaux
Parasite-mediated selection has driven the emergence of complex hosts’ defense mechanisms to limit the spread of parasites. In addition to their physiological immune system, animals have developed a “behavioral immune system” comprising a sophisticated set of parasite avoidance strategies that represents a first line of defense to decrease parasite encounter rates. However, behavioral adaptations to the threat of parasites have been poorly investigated in wild populations of mammals. In an attempt to fill this gap, during my PhD, I studied parasite avoidance strategies in a wild group of mandrills (Mandrillus sphinx), an Old World primate inhabiting dense equatorial rainforests of Africa and facing intensive parasite pressures in its natural habitat. In particular, I investigated the different behavioral strategies of defense that evolved to decrease contamination risk by two different classes of gastro-intestinal parasites exhibiting contrasted life-history traits and modes of transmission: environmentally transmitted nematodes and socially transmitted protozoa. Based on long-term observations, controlled experiments and chemical analyses, my studies document two distinct behavioral strategies emphasizing the close relationship between parasites’ ecology and hosts’ behavioral responses. On the one hand, mandrills exhibit fecal avoidance behavior when foraging and also avoid ranging in habitats previously contaminated with fecal nematodes released during the previous visit. On the other hand, mandrills avoid grooming social partners highly parasitized with fecal protozoa, particularly around the peri-anal area. This behavioral strategy appears to be operational because parasitized individuals harbor infectious protozoan cysts on their body, concentrated on the peri-anal region, and individual’s protozoan richness increases when grooming highly parasitized conspecifics. We further found that avoidance of parasitized individuals is guided by an olfactory mechanism, as protozoa influence the host’s fecal odor and mandrills discriminate and selectively avoid olfactory cues from individuals parasitized with protozoa. Such parasite-induced behavioral plasticity could be one of the major mechanisms allowing social species to cope with the increased risk of parasitism associated with group-living. Altogether, these findings shed light on the evolutionary consequences of parasite-mediated selection on several socioecological characteristics of animals, including space use and social behavior
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Ward, Megan E. "Parasitism in Deep-Sea Chemosynthetic Mussels: Parasitism in Bathymodiolus Mussels from Deep-Sea Seep and Hydrothermal Vents." W&M ScholarWorks, 2004. https://scholarworks.wm.edu/etd/1539626457.

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20

Araujo, Vinicius Queiroz. "Alterações celulares e teciduais de Echinodermata em resposta ao parasitismo por moluscos eulimídios (Gastropoda: Eulimidae)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-09032015-121037/.

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Assim como visto nos vertebrado, os invertebrados também possuem um sistema imune bastante complexo, apresentando respostas humorais e celulares. Esta última é a principal forma de defesa, envolvendo células amebóides móveis capazes de isolar e/ou eliminar material estranho. Em equinodermos, as células envolvidas nestas respostas são categorizadas como celomócitos, uma denominação genérica que engloba vários tipos celulares encontrados nas cavidades corporais e no tecido conjuntivo. Entretanto, além da função imune, são reportados como tendo outros papéis diversos, como excreção, digestão, transporte e estocagem de nutrientes e a síntese e deposição de fibras de colágeno e da matriz extracelular Não existe consenso sobre quais os papéis específicos desempenhados por estas células num organismo saudável e nem diante de um processo inflamatório. Assim, o presente trabalho foi realizado para caracterizar o processo inflamatório no espinho de Eucidaris tribuloides causado por sabinella troglodytes, um molusco ectoparasita no espinho. A primeira parte do trabalho traz a caracterização das células da cavidade celomática. Para investigá-las foi realizada uma abordagem integrada onde os celomócitos foram descritos por meio da utilização de células vivas, citoquímica e microscopia eletrônica de transmissão. Foram encontrados sete tipos celulares, sendo um novo e dois pouco conhecidos. Com esta abordagem inicial, foi possível obter as ferramentas necessárias para investigar o processo inflamatório. Para estudar o processo inflamatório no espinho de E. tribuloides, utilizou-se uma abordagem estrutural, combinando histologia, microscopia eletrônica de varredura e microtomografia computadorizada, assim como celular/molecular. Os dados indicam que a inflamação causada pelo molusco parece ser um evento local, que altera tanto a matriz orgânica quanto a calcária, mas parece não se propagar para a cavidade celomática do hospedeiro
The invertebrates, as well as vertebrates, also have a very complex immune system, presenting humoral and cellular responses. The latter is their main form of defense, involving mobile amoeboid cells capable of isolating and/or eliminating foreign material. In Echinodermata, the cells involved in these responses are categorized as coelomocytes. This is a generic term that encompasses various cell types found in the body cavities and connective tissue. However, in addition to immune function, they are reported as having various other roles, such as excretion, digestion, transport and nutrient storage and the synthesis and deposition of collagen fibers and extracellular matrix. There is no consensus on what the specific role played by each one of these cells in healthy individuals and the knowledge about the inflammatory process is much worse. Thus, the present study was performed to characterize the inflammatory process in the spine of Eucidaris tribuloides caused by Sabinella troglodytes, a spine ectoparasites gastropod. The first part of the study provides the characterization of the cells of the coelomic cavity. To investigate them, an integrated approach was used, where the coelomocytes were described through the use of living cells, immunocytochemistry and transmission electron microscopy. Seven cell types were found: one new and two poorly known. This initial approach enables us to obtain the necessary tools to investigate the inflammatory process. To study the inflammatory process in the spine of E. tribuloides, we used a structural approach, combining histology, scanning electron microscopy and computed microtomography, and the cellular/molecular one. The data indicate that inflammation caused by snail appears to be a local event, which alters both the organic and calcareous matrix, but does not seem to be reflected within the coelomic cavity of the host
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Soutello, Ricardo Velludo Gomes de. "Influência do parasitismo e da suplementação no desenvolvimento ponderal de novilhos mestiços Angus-Nelore e da raça Guzerá /." Ilha Solteira : [s.n.], 2001. http://hdl.handle.net/11449/98643.

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Orientador: Maria Conceição Zocoller Seno
Banca: Bruno Soerensen Cardoso
Banca: Wilma Aparecida Starke Buzetti
Resumo: Analisou-se os efeitos do tratamento anti-helmíntico estratégico e da suplementação protéica no ganho de peso de novilhos, do desmame até o abate. Foram utilizados 40 animais, com 8-9 meses de idade, 20 da raça Guzerá e 20 mestiços (Nelore - Angus), pesando em média 211,8 Kg. Esses animais foram distribuídos em quatro lotes, conforme o peso e permaneceram em quatro piquetes de aproximadamente 10 hectares cada, formado por Brachiaria decumbens. Dois lotes, grupos 1 e 2, receberam suplementação protéica comercial com 50 % de proteína bruta durante a seca e com 15 % durante as águas, fornecido "ad libitum", e dois receberam somente mistura mineral, grupos 3 e 4 (controle). Dos lotes que receberam suplementação, apenas um foi tratado com endectocida Moxidectin 1% (grupo 1), o mesmo ocorrendo para os que receberam a mistura mineral (grupo 3). A cada 28 dias, os animais foram pesados e suas fezes colhidas para a contagem de ovos por grama de fezes (OPG) e coprocultura, e a cada 14 dias foi feito contagem de carrapatos de um lado do animal. O ganho de peso dos animais dos grupos um, dois, três e quatro foram de: 0,453 Kg, 0,320 Kg, 0,339 Kg e 0,231 Kg, por dia, respectivamente. Observou-se uma diferença significativa de peso entre os animais suplementados e tratados (grupo 1) em relação aos animais apenas tratados (grupo 3) e apenas suplementados (grupo 2), que por sua vez também foram significativamente diferentes dos animais que não receberam tratamento nem suplementação (grupo 4). A média de OPG nos grupos um, dois, três e quatro foi de: 19,82; 275,98; 31,34 e 254,55 respectivamente, com diferença significativa entre os animais tratados com anti-helmíntico (grupos 1 e 3) e os não tratados (grupos 2 e 4). As contagens médias de carrapatos nos grupos um, dois, três e quatro foram de: 1,2; 7,7; 0,8 e 9,3 respectivamente, com diferença... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: The effect of strategic anthelmintic treatment and protein suplementation was evaluated in steers using the weight gain as a parameter, during the period from weans to slawghtery. Forty animals were used, with 8-9 months of age, 20 of Guzera breed (Bos indicus) and 20 Nelore - Angus, weighing 211.8 kg in average. These animals were distributed in four groups and remained in four paddoks of 10 hectares each, formed by Brachiaria decumbens. Two groups had received commercial protein suplement with 50% of crude protein during the dry period and with 15% of crude protein, during the wet period, supplied "ad libitum" (groups 1 and 2) and the others two received only mineral mixture; groups 3 and 4 (control group). From those animals that received protein suplement, only one was treated with anthelmintic 1% Moxidectin (group 1), the same occurring for those animals that received mineral mixture (group 3). At 28 days of intervals the animals were weighed and theirs fecal samples were collected for nematode egg counts (EPG) and larval cultures, and at 14 days of intervals ticks were counted on a half of animal. The weight gain in group 1, 2, 3 and 4 was: 0.453 kg, 0.320 kg, 0.339 kg and 0,231 kg per day, respectively. Statistical significace of weight gain occurred between the animals supplemented and medicated (group 1) in relation to the animals that were only medicated (group 3) or betweem the groups that were only supplemented (group 2), and no medicated and suplemented (group 4). The average of EPG in groups 1, 2, 3 and 4 was of: 19.82; 275.98; 31.34 and 254.55 respectively, with significant difference in the animals medicated with anthelmintic (groups 1 and 3) and no medicated (groups 2 and 4). The tick counts in groups 1, 2, 3 and 4 was of: 1,2; 7,7; 0,8 e 9,3 respectively, with significant difference in the animals medicated (groups 1 and 3) and no... (Complete abstract, click electronic address below).
Mestre
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22

Houngbédji, Tossimidé. "Rhamphicarpa fistulosa : infestation dans les bas-fonds rizicoles de la Région des Savanes (Togo) et étude des interactions hôte-parasite." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS455/document.

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Une des contraintes biotiques majeures de la riziculture de bas-fond au nord du Togo est l’adventice parasite Rhamphicarpa fistulosa (Hochst.) Benth. Afin d’évaluer les options stratégiques pour contrôler efficacement R. fistulosa, notre étude a été conduite avec comme principaux objectifs : 1) l’identification de la répartition de R. fistulosa et l’étude des facteurs qui favorisent son infestation, 2) l’étude de l’impact des niveaux d’infestation sur la flore adventice du riz, et 3) la caractérisation des interactions hôte-parasite et de leurs impacts sur le développement de l’hôte et les performances reproductives du parasite. A l’issu des prospections de terrain, les plus fortes infestations ont été retrouvées sur des sols majoritairement à texture sableuse et très pauvres en matière organique. Une flore adventice très diversifiée a été retrouvée en présence de R. fistulosa, certaines adventices pouvant être parasitées et constituer éventuellement un réservoir pour accroître le stock semencier du parasite. En conditions contrôlées, R. fistulosa se développe et se reproduit aussi bien sur le riz que sur la tomate, alors que le soja retarde la reproduction du parasite. La germination des graines de R. fistulosa est maximale en présence de graines de plantes cultivées ou adventices. Les graines nouvellement récoltées ont une dormance de plus de six mois, mais leur germination a été stimulée par la présence de phytohormones. En conclusion, les meilleures stratégies de lutte doivent impliquer le contrôle par les semis tardifs, les rotations culturales avec les légumineuses comme le soja, l’arachide ou le niébé, et les cultures maraîchères
Main biotic constraints to rain-fed lowland rice cultivation in northern Togo include the parasitic weed Rhamphicarpa fistulosa (Hochst.) Benth. In order to evaluate efficient strategies to control R. fistulosa, our study was performed taking into account the following main objectives: 1) Identification of the distribution of R. fistulosa and study of the factors favouring its infestation, 2) Study of the impacts of infestation levels on rice weed communities, and 3) Characterization of the host-parasite interactions and their impacts on the host development and the parasite reproduction. Following fields investigations, highest infestations were observed on sandy soils with low levels of organic matter.In addition, weed flora found in the presence of R. fistulosa was much diversified and some weeds were found to been parasitized and could possibly constitute reservoirs to increase the seed stock of the parasite. In controlled experiments, R. fistulosa grown and reproduced better on rice and tomato crops, than on soybean which delayed the reproduction of the parasite. Germination of R. fistulosa seeds was stimulated in presence of cultivated crops or weeds. New collected seeds shown six months dormancy but their germination was stimulated in presence of phytohormones. In conclusion, the best strategies to control R. fistulosa must include delayed sowing, crop rotation with leguminous species (i.e. soybean, peanut or cowpea) and vegetable cropsKeywords: Rhamphicarpa fistulosa, rice, lowland, parasitism, host-parasite interaction, weeds
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23

Patel, Nrupali. "Functional Analyses of Cyst Nematode Parasitism Genes." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-03102008-221413/.

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Cyst nematodes in the genus Heterodera are sedentary endoparasites that induce elaborate feeding cells within host roots by secreting proteins produced within nematode esophageal glands into plant cells. Functional analyses of selected cyst nematode parasitism genes that encode such secreted proteins was the objective of this dissertation. Homologs of four parasitism genes initially isolated from Heterodera glycines, including Hg4F01 (annexin-like protein), HgSYV46 (CLAVATA3-like plant peptide mimic), Hg4E02 and Hg5D08 (novel proteins with putative host nuclear localization) were isolated from Heterodera schachtii, which can infect Arabidopsis thaliana. Greater than 90% nucleotide and predicted amino acid identity existed between the four parasitism genes homologs of H. glycines and H. schachtii. mRNA in situ hybridization and immunolocalization confirmed the expression of each gene product exclusively within the nematode esophageal gland cells. Since eukaryotic annexins affect many cellular processes involving calcium-dependent membrane association, the potential function of the Hs4F01 secreted into plant cells was analyzed. Similar to annexin mutants in Arabidopsis, transgenic Arabidopsis expressing Hs4F01 produced no observable plant phenotype, but were more susceptible to nematode infection. Hypersensitivity to osmotic stress in an Arabidopsis annAt1 annexin mutant was reduced (complemented) in mutants that expressed Hs4F01, suggesting a functional similarity of nematode and plant annexins within plant cells. Host derived RNA interference (RNAi) to silence Hs4F01 transcripts significantly reduced the number of H. schachtii females developing on roots that express dsRNA to Hs4F01. Expression of Hs4E02 and Hs5D08 in Arabidopsis produced no observable plant phenotype and susceptibility to H. schachtii was not altered in plants that expressed Hs4E02. Silencing of HsSYV46 using host-derived RNAi demonstrated a significant reduction in the development of nematode females on Arabidopsis roots that expressed double-stranded RNA to HsSYV46. Expression of dsRNA to Hs4E02 and Hs5D08 in Arabidopsis roots did not affect nematode susceptibility. In summary, parasitism gene products confirmed to have cellular functions similar to their plant homologs, including Hs4F01 (annexin-like protein) and HsSYV46 (CLAVATA/ESR-like peptide) were demonstrated by RNAi to have a significant biological role in cyst nematode parasitism of host plant roots.
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24

Johnson, Alice P. "Host variability and parasitism in Bombus terrestris." kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:29744.

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25

Rupp, Jens C. "Mate choice and parasitism in freshwater snails." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339354.

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26

Garamszegi, László Zsolt. "Parasitism and the evolution of bird song." Paris 6, 2002. http://www.theses.fr/2002PA066149.

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27

Kaliszewska, Zofia. "Evolution of Parasitism in the Lycaenidae (Lepidoptera)." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23845507.

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Of the four most diverse insect orders, the Lepidoptera contain remarkably few predatory and/or parasitic taxa, and while species with carnivorous life histories have evolved independently numerous times in moths and butterflies, this has rarely led to diversification. As a rule, aphytophagous taxa seem prone to extinction. In this dissertation, I explore the ecological and evolutionary consequences of entomophagy in the butterfly family Lycaenidae using several approaches: natural history observation, phylogenetics, population genetics and stable isotope chemistry. A striking exception to the lack of radiation and persistence in aphytophagous lineages is the lycaenid subfamily Miletinae, which with 13 genera and 190 species is among the largest and most diverse groups of aphytophagous Lepidoptera. Most miletines eat Hemiptera, although some consume ant brood or are fed by trophallaxis from their host ant. I inferred the higher-level phylogeny of this group using data from one mitochondrial and six nuclear genes sampled from representatives of all genera and nearly half the described species. Biogeographic analyses indicate that Miletinae likely diverged from an African ancestor near the start of the Eocene, and four lineages dispersed between Africa and Asia. Phylogenetic constraint in prey selection is apparent at two levels: related miletine species are more likely to feed on related Hemiptera and are also more likely to associate with closely related ants species, either directly by eating the ants, or indirectly by eating hemipteran prey attended by those ants. I then examined the influence of diet on the population structure of lycaenid butterflies, and more specifically, I investigated whether particular feeding habits are correlated with traits that might make species vulnerable to extinction. To do this, I compared the phylogeography and population genetics of two endemic lycaenid species of roughly similar age from southern Africa: Chrysoritis chrysaor, whose caterpillars are strictly herbivorous, and Thestor protumnus, whose cuckoo-like caterpillars survive by soliciting regurgitations from their host ants. I sampled both species from populations throughout their entire known ranges, and found that in contrast to C. chrysaor, T. protumnus has exceedingly small effective population sizes and individuals disperse poorly. With its aphytophagous life history, T. protumnus exhibits a high degree of host dependence and specialization. Although these results are correlative and based on only a single comparison, it seems likely that small population sizes and extreme ecological specialization make populations of T. protumnus more susceptible to disturbance and prone to extinction. Having focused in detail on the population biology of just one species, I then analysed the evolution of Thestor as a whole. This genus is exceptional because all of its 27 described species are thought to be entomophagous, and all are thought to be predators or parasites of a single species of ant, Anoplolepis custodiens. Using representatives sampled from all known species and populations of Thestor as well as 15 outgroup species, I inferred the phylogeny of the genus in two ways: first by using characters from mitochondrial and nuclear genes, and second by analyzing genome-wide SNPs generated for each species using double digest RADseq. I also sequenced the ants associated with each of these taxa using ddRADseq. This investigtion showed that all 24 of the species in the Western Cape utilize Anoplolepis custodiens, while T. protumnusand T. dryburghi (the two species that are found in the north-western part of South Africa) use a closely related, but different species of Anoplolepis, and T. basutus (the species found in the eastern part of South Africa) utilizes yet a third species. Thus factors driving diversity in the genus Thestor may have initially involved ant associations and/or geographic isolation, but other forces are likely to be responsible for generating and maintaining the more recent diversity in the group. Flight time may have separated the “black” and “yellow” groups of Thestor: the black group fly predominantly in the summer months, while the yellow group fly predominantly in the spring. And while species spread across the genus fly in the spring and summer months, only members of the yellow group fly during the winter and fall months. Despite these broad scale differences, species in the genus Thestor show little evidence of niche partitioning, especially those in the Western Cape, and represent an extreme example of the coexistence of 24 species apparently utilizing a single food resource. While working on the previous three projects, I was surprised by the number of species of South African Lycaenidae with incomplete life histories despite decades of work by avid lepidopterists in the region. For example, in the genus Thestor, although all 27 species are assumed to be aphytophagous, partial life histories have been described for only four species. In part the paucity of data is due to the difficult terrain occupied by these butterflies, and the fact that those whose caterpillars associate with ants often spend significant portions of their lives hidden in ant nests in crevices of rock that are intractable for excavation and observation. To deepen our understanding of South African lycaenid life histories, I used nitrogen and carbon stable isotopic methods to survey a large number of species and their potential food sources. With these methods, I confirmed some known or suspected life histories and showed that in any one area, a species can have a highly variable diet. I also discovered that some of the nitrogen stable isotope values are much higher than expected for land animals, implying longer than average food chains and/or extreme environmental conditions. Together, these studies shed light on how carnivorous life histories affect the evolution of lycaenid butterflies, and help to explain why entomophagous lineages appear to be an evolutionary “dead end” in contrast to their herbivorous counterparts.
Biology, Organismic and Evolutionary
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28

Jackson, Wendy M. "Conspecific nest parasitism in the Northern Masked Weaver /." Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/5183.

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29

Delaire, Lari. "Predation, parasitism and colour in natural guppy populations." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103592.

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Many studies of evolution adopt a unifactorial approach, where a single causal force appearing to account for a majority of the phenotypic variation becomes the focal point of investigation. However, it seems certain that no single force acts to the complete exclusion of other forces, and so multi-factorial studies can make a crucial contribution to our understanding of the evolution of phenotypic variation. In the Trinidadian guppy system, natural selection acting via predation has long been recognized as playing an important role in shaping trait variation. However, other environmental factors also likely contribute, and my thesis explores the potential role of one of them: parasitism. I specifically focus on Gyrodactylus, a monogenean ectoparasite that has important effects on many fish species and coexists with guppies in the wild. I evaluate the extent to which parasitism varies among guppy populations, particularly in relation to predation. I then ask whether parasitism influences phenotypic variation in guppy traits. This work was executed through a large-scale survey in northern Trinidad, where 26 guppy populations of known predation level (high or low) were surveyed across 10 different rivers. Individual guppies were scanned for Gyrodactylus and then photographed for image analyses aimed at quantifying body size and aspects of male colour. I found that among-population variation in parasitism levels was consistent between two dry seasons, and that high-predation localities tend to have higher levels of parasitism than do low-predation localities. However, I found few effects of parasitism on guppy traits and no major modifying influence of parasitism on inferences about the role of predation. Although more work certainly needs to be done with respect to parasitism, our results suggest it might be more profitable to concentrate on other potential causal factors that shape guppy trait variation.
De nombreuses études sur l'évolution adoptent une approche uni-factorielle qui se concentrent sur une seule force pouvant expliquer la plupart de la variation phénotypique observée. Cependant, il est évident qu'aucune force n'exerce son effet de façon isolée. C'est pourquoi les études multi-factorielles apportent une contribution cruciale à notre compréhension de l'évolution de la variation phénotypique. Dans le système d'étude des guppies de Trinité, la sélection naturelle imposée par les prédateurs a depuis longtemps été considérée comme un facteur important dans l'élaboration de la variation au niveau des traits. Cependant, d'autres facteurs environnementaux contribuent également à cette élaboration, notamment le parasitisme. Je me penche sur le rôle potentiel que peuvent avoir les parasites du genre Gyrodactylus sur les traits des guppies. Ces ectoparasites monogènes exercent de nombreux effets sur plusieurs espèces de poissons et coexistent avec les guppies dans leur environnement naturel. J'évalue le niveau de variation du parasitisme entre les populations de guppies, et plus spécifiquement en relation avec la prédation. J'explore par la suite l'influence potentielle du parasitisme sur la variation phénotypique des traits des guppies. Pour ce faire, une étude de grande échelle a été effectuée sur 10 rivières dans le nord de Trinité, dans laquelle 26 populations sujettes à des niveaux de prédation connus (élevé ou bas) ont été inventoriées. L'état d'infection par les Gyrodactylus a été répertorié pour chaque guppy, puis les poissons ont été photographiés pour analyser les images dans le but de quantifier la taille corporelle ainsi que de nombreux aspects de la coloration chez les mâles. J'ai trouvé que les niveaux de parasitisme entre les populations étaient consistants entre les deux saisons sèches recensées, et qu'il y a une tendance pour les sites de haute prédation à avoir des niveaux de parasitisme plus élevés que les sites de basse prédation. Cependant, j'ai trouvé que la parasitisme avait peu d'effets sur les traits des guppies et aucune influence majeure n'a été trouvée sur les inférences concernant la prédation. Bien qu'il reste encore beaucoup de travail à faire en ce qui a trait au parasitisme, nos résultats suggèrent qu'il pourrait être plus profitable de se concentrer sur d'autres facteurs potentiels pouvant expliquer la variation de traits chez les guppies.
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30

Whitehorn, Penelope R. "The impact of inbreeding and parasitism on bumblebees." Thesis, University of Stirling, 2011. http://hdl.handle.net/1893/3454.

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Many bumblebee species are suffering from the effects of habitat fragmentation and population isolation. In some cases, populations have lost genetic diversity due to genetic drift and it is possible they are now at heightened risk of extinction. Inbreeding may be particularly costly to bumblebees because, as Hymenoptera, their complementary sex determination system can lead to the production of sterile or inviable diploid males. However, little is known about the effect that diploid male production has on bumblebee colony fitness. Here, the consequences of brother-sister mating in the bumblebee Bombus terrestris are investigated, and the production of diploid males was found to exert considerable costs at the colony level by reducing productivity and survival. Diploid males may therefore act as indicators of the genetic health of populations, and their detection could be used as an informative tool in hymenopteran conservation. Due to the costs associated with inbreeding, selection may have favoured the evolution of kin recognition systems in bumblebees. Data are presented that suggest that B. terrestris can discriminate between kin and non-kin as gynes were less willing to mate with siblings compared to non-relatives. Theory predicts that inbreeding may impose further costs on bumblebees through increased levels of parasitism, but empirical data are scarce. The relationship between population genetic diversity and parasite prevalence is assessed using Hebridean island populations of Bombus muscorum and Bombus jonellus. In the more outbred B. jonellus, there was no relationship between parasite prevalence and population heterozygosity. But prevalence of the gut parasite Crithidia bombi and the tracheal mite Locustacarus buchneri were found to be higher in populations of B. muscorum that had lower genetic diversity. In addition to assessing infection status, the activity of the immune system was assessed in each individual bee. However, there was no relationship between population heterozygosity and these immune parameters. This suggests that, in some Hymenopteran species, as populations lose genetic diversity the impact of parasitism will increase, potentially pushing threatened populations closer to extinction. Therefore, preventing population fragmentation by the creation of suitable habitats and by ensuring connectivity between habitat patches are important aspects of hymenopteran conservation. Finally, this thesis investigates the potential threat of pathogen spread from commercially reared bumblebees used for crop pollination to wild bumblebees. Although no direct evidence for parasite spillover is found, the prevalence of C. bombi was significantly higher in B. terrestris by the end of the season on farms that used commercial bumblebees compared to farms that did not. This high prevalence does suggest that pathogen spillover is a potential threat and it would be preferable to reduce the usage of commercial bumblebees where possible. For example, sowing wild flower mixes could boost natural pollinator populations, which in turn would benefit soft fruit pollination. Overall, this thesis contributes to our knowledge of the consequences of inbreeding in bumblebees and the relationship between genetic diversity and parasite prevalence. It provides a greater understanding of the factors that might be pushing threatened pollinators towards extinction and as a whole provides important information that may inform conservation practitioners, whose aim is to protect the future of our hymenopteran pollinators.
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31

Lindholm, Anna Kristina. "Evolution of host defences against avian brood parasitism." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627230.

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32

Watters, George Murray. "Models of parasitism and hyperparasitism on Paralomis spinosissima /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9823698.

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33

Whiting, James R. "The evolutionary consequences of genetic adaptation to parasitism." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/50591/.

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The processes driving and maintaining variable immune responses are poorly understood compared with other aspects of an organism’s ecology. This is particularly true from an evolutionary perspective, as the evolutionary relationships between immune responses and other traits and processes in nature remain inadequately explored. I investigated these associations in this thesis using the three-spined stickleback system as an evolutionary and immunological model. I combined sampling of wild individuals with genomic analyses to demonstrate phenotypic and genomic associations between immune responses and life history evolution across multiple populations. I also observe how experimental changes in daylength, a seasonal cue, modulate immune responses and increase parasite susceptibility in a controlled laboratory experiment. These findings occur independently of natural variation in parasite resistance. Stickleback are also a model for studies of speciation. I used sampling of wild hybrids to assess the significance of immune variation in postzygotic isolating mechanisms between diverging ecotypes; although my findings suggest a minor role. Finally, I demonstrate that genomic responses to parasitism and abiotic environmental variation are repeatable across independent, intercontinental adaptive radiation events in sticklebacks; conferring a repeatability of the evolutionary relationships of immune variation documented in this thesis. The findings within this thesis therefore provide novel insights into poorly explored or open areas of research regarding how variable immune responses evolve in nature.
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34

Bezerra, Rayanna Hellem Santos. "Ectoparasitos de morcegos em área de restinga, Sergipe: uma análise ecológica e filogenética." Pós-Graduação em Ecologia e Conservação, 2018. http://ri.ufs.br/jspui/handle/riufs/8004.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The structuring of the bat parasite community can be influenced by the seasonality, body size, sex, geographical distribution and evolutionary history of the host. This study aimed to characterize the community of ectoparasites associated with bats in the restinga area, Sergipe; as well as to present the parasitological descriptors and the association of the parasitism with the body size and sex of the host. Field campaigns were held monthly for two consecutive nights between October 2016 and September 2017. For the capture of bats, 10 mist nets were placed inside the restinga and the collected ectoparasites were stored in 70% alcohol. For the parasitized bats the parasitological rates and the index of specificity were obtained and the infracommunities were recorded. The influence of host body size on the richness and abundance of ectoparasites through linear regression was evaluated. For the most abundant ectoparasites, the influence of the sex of the host on the prevalence rate was verified through the chi-square test and the mean intensity through the t-test. For the influence of seasonality on the same rates GLM was performed. The relationship between the geographic extent of host occurrence and the richness of ectoparasites was evaluated by means of linear regression. In order to verify if phylogenetically closest hosts shared parasites, a Mantel test was performed. The parasitized bats belong to the families Phyllostomidae (N = 163; S = 11) and Vespertilionidae (N = 3; S = 2). The ectoparasites correspond to the families Spinturnicidae (N = 131; S = 1), Argasidae (N = 30; S = 2), Nycteribiidae (N = 9; S = 2) and Streblidae (N = 260; S = 13). The most abundant ectoparasites were Periglischrus iheringi and Trichobius joblingi. The registered infracommunities are composed by species of different genera. There was no influence of host body size on parasitism, which may be associated with the similarity between host body mass. The influence of the sex of the host on the prevalence rate between Artibeus lituratus and P. iheringi, being the most parasitized females, can be explained by their higher susceptibility to parasitism due to the longer stay in the shelters. Regarding seasonality, differences in prevalence rates and mean intensity were observed for the association between Carollia perspicillata and T. joblingi, with higher values during the season with lower temperature. This influence may be due to biological differences between parasite species. It was possible to observe an increase in the richness of ectoparasites with the increase of the geographical extension of the host, which can be explained by the fact that hosts with a wide distribution are more likely to encounter the parasites. There was no relation between the phylogenetic proximity of the hosts and the sharing of parasites, being able to be related to the different biogeographic patterns of the areas. This study presents important information related to the host-parasite interaction, especially for Sergipe, highlighting the need for more analysis involving the theme in order to better understand the factors that shape this relationship.
A estruturação da comunidade de parasitos de morcegos pode ser influenciada pela sazonalidade, tamanho corporal, sexo, distribuição geográfica e história evolutiva do hospedeiro. Esse estudo teve como objetivo caracterizar a comunidade de ectoparasitos associados a morcegos em área de restinga, Sergipe; bem como apresentar os descritores parasitológicos e a associação do parasitismo com o tamanho corporal e sexo do hospedeiro. As campanhas de campo foram realizadas mensalmente, durante duas noites consecutivas, entre outubro/2016 e setembro/2017. Para a captura de morcegos foram dispostas 10 redes de neblina no interior da mata e os ectoparasitos coletados foram armazenados em álcool 70%. Para os morcegos parasitados obtiveram-se as taxas parasitológicas, o índice de especificidade e registraram-se as infracomunidades. Foi avaliada a influência do tamanho corporal do hospedeiro sobre a riqueza e abundância de ectoparasitos através de regressão linear. Para os ectoparasitos mais abundantes foi verificada a influência do sexo do hospedeiro na taxa de prevalência, através do teste qui-quadrado, e na intensidade média através do teste t. Para a influência da sazonalidade sobre as mesmas taxas foi realizado GLM. A relação entre a extensão geográfica de ocorrência do hospedeiro e a riqueza de ectoparasitos foi avaliada por meio de regressão linear. A fim de verificar se hospedeiros filogeneticamente mais próximos compartilham parasitos, foi realizado teste de Mantel. Os morcegos parasitados pertencem às famílias Phyllostomidae (N=163; S=11) e Vespertilionidae (N=3; S=2). Os ectoparasitos correspondem às famílias Spinturnicidae (N=131; S=1), Argasidae (N=30; S=2), Nycteribiidae (N=9; S=2) e Streblidae (N=260; S=13). Os ectoparasitos mais abundantes foram Periglischrus iheringi e Trichobius joblingi. As infracomunidades registradas são compostas por espécies de diferentes gêneros. Não houve influência do tamanho corporal do hospedeiro sobre o parasitismo, o que pode estar associado à similaridade entre a massa corporal dos hospedeiros. A influência do sexo do hospedeiro na taxa de prevalência entre Artibeus lituratus e P. iheringi, sendo as fêmeas mais parasitadas, pode ser explicada pela maior suscetibilidade destas ao parasitismo decorrente do maior tempo de permanência nos abrigos. Em relação à sazonalidade, foram observadas diferenças nas taxas de prevalência e intensidade média para a associação entre Carollia perspicillata e T. joblingi, com maiores valores durante a época com temperatura menor. Essa influência pode ser decorrente das diferenças biológicas entre as espécies de parasitos. Foi possível observar um aumento na riqueza de ectoparasitos com o aumento da extensão geográfica do hospedeiro, o que pode ser explicado pelo fato de hospedeiros com ampla distribuição possuírem maior probabilidade de encontro com os parasitos. Não houve relação entre a proximidade filogenética dos hospedeiros e o compartilhamento de parasitos, podendo estar relacionado aos diferentes padrões biogeográficos das áreas. Esse trabalho traz informações importantes relacionadas à interação parasito-hospedeiro, ressaltando a necessidade de mais análises envolvendo o tema a fim de compreender melhor os fatores que moldam essa relação.
São Cristóvão, SE
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35

Louradour, Isabelle. "Réponse au parasitisme par des guêpes chez la drosophile : rôle de la voie de signalisation Toll/NFkB." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30256/document.

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Dans tous les organismes animaux la réponse immunitaire est divisée en deux composantes : la réponse humorale, qui consiste en la production d'un grand nombre de molécules toxiques pour le pathogène, et la réponse cellulaire, qui met en jeu des cellules immunitaires produites lors de l'hématopoïèse. Chez les mammifères adultes, l'hématopoïèse se déroule dans la moelle osseuse, où un microenvironnement particulier appelé " niche hématopoïétique " contrôle l'auto-renouvèlement, la prolifération et la différenciation des Cellules Souches Hématopoïétiques (CSH) à l'origine de l'ensemble des cellules sanguines/immunitaires. Suite à une infection par un pathogène, l'homéostasie du système hématopoïétique est modifiée, afin de permettre la mise en place d'une réponse immunitaire cellulaire adaptée. Le rôle de la niche hématopoïétique dans le contrôle de l'hématopoïèse suite à une infection reste à ce jour mal connu. La drosophile est utilisée comme système modèle pour étudier in vivo l'hématopoïèse et la réponse immunitaire. L'hématopoïèse a lieu chez la drosophile au stade larvaire dans un organe spécialisé appelé Glande Lymphatique (GL). Au sein de cet organe, un petit groupe de cellules, le Centre de Signalisation Postérieur (PSC), contrôle l'équilibre entre progéniteurs hématopoïétiques et cellules immunitaires différenciées, et a donc un rôle équivalent à celui de la niche hématopoïétique des mammifères. Suite à un stress immun, tel que le parasitisme par des guêpes, une différenciation massive de cellules immunitaires spécifiques, les lamellocytes, a lieu dans la GL; puis la dispersion de la GL permet la libération des lamellocytes dans la circulation lymphatique. Lors du parasitisme, la guêpe pond un œuf dans le corps de la larve de drosophile. En absence de réponse immunitaire cellulaire, l'œuf de guêpe se développe au dépend de son hôte, entraînant sa mort. En formant une capsule autour de l'œuf de guêpe, les lamellocytes neutralisent son développement et permettent la survie de l'hôte. Au cours de ma thèse, je me suis intéressée à la réponse immunitaire cellulaire de la larve de drosophile au parasitisme par des guêpes. Je me suis plus particulièrement intéressée au rôle de la " niche hématopoïétique " dans cette réponse. Pour cela, j'ai initié une approche transcriptomique ayant pour but d'identifier les gènes spécifiquement exprimés dans le PSC en réponse au parasitisme. En parallèle, j'ai caractérisé le rôle de la voie de signalisation Toll/NF?B dans la GL lors de la réponse au parasitisme. La voie Toll/NF?B joue un rôle essentiel dans la réponse immunitaire humorale et son rôle dans la réponse immunitaire cellulaire reste à définir. Mes travaux indiquent que la voie Toll/NF?B est activée dans le PSC suite au parasitisme. Son activation est médiée par le facteur de transcription NF?B "Dorsal-related Immunity Factor" (Dif), qui est requis dans le PSC pour permettre la différenciation rapide et massive de lamellocytes et la dispersion des cellules de la GL. De plus, j'ai établi un réseau génique, impliquant les deux voies de signalisation Toll/NF?B et EGFR ainsi que les espèces réactives de l'oxygène (ROS) dans le contrôle de la réponse au parasitisme. Une augmentation du niveau de ROS dans le PSC et l'activation de la voie EGFR dans les cellules immunitaires ont été décrits comme nécessaires à l'encapsulation des œufs de guêpe après parasitisme. Mes données établissent qu'ils sont en plus requis respectivement dans les cellules du PSC et dans les progéniteurs hématopoïétiques pour permettre la dispersion de la GL après parasitisme. Basé sur la forte conservation des voies de signalisation et processus moléculaires contrôlant l'hématopoïèse entre les mammifères et la drosophile, mes résultats posent la question de la conservation du réseau génique établi chez la drosophile et du rôle de la voie NF?B dans la niche hématopoïétique des mammifères lors d'une réponse à une infection
In all organisms, the immune response is divided into two parts: the humoral response, which consists of producing a large number of molecules to combat the pathogen, and the cellular response, which relies on immune cells produced during hematopoiesis. In adult mammals, hematopoiesis occurs in the bone marrow, where a particular microenvironment called the "hematopoietic niche" controls self-renewal, proliferation and differentiation of Hematopoietic Stem Cells (HSCs), which give rise to all blood cell types. Following a pathogenic infection, the hematopoietic system's homeostasis is modified in order to obtain an adapted cellular immune response. The role that the hematopoietic niche plays during an immune response remains unclear. Drosophila is used as a model system to study in vivo hematopoiesis and the immune response. In drosophila, hematopoiesis occurs at the larval stage in a specialized organ called the Lymph Gland (LG). Within this organ, a small group of cells termed the Posterior Signalling Center (PSC), controls the balance between hematopoietic progenitors and differentiated immune/blood cells, a role similar to the mammalian hematopoietic niche. Following an immune challenge, especially in response to wasp parasitism, a massive differentiation of specific immune cells called lamellocytes occurs in the LG. The LG subsequently disperses to release lamellocytes into the hemolymph. During parasitism, the wasp lays an egg in the drosophila larva. In the absence of a cellular immune response, the wasp egg will develop and kill its host. By forming a capsule around the wasp egg, lamellocytes impede the pathogen's development and permit the host's survival. During my PhD, I studied the drosophila larva cellular immune response to wasp parasitism. I focused my research on the role of the "hematopoietic niche". I therefore initiated a transcriptomic study, in order to identify genes expressed by the PSC in response to parasitism. In parallel, I characterized the role of the Toll/NF?B signalling pathway in the LG during parasitism. The Toll/NF?B pathway plays a key role in the humoral response both in drosophila and mammals; however its role in the cellular immune response remains unknown. My results indicate that the Toll/NF?B pathway is activated in the PSC following parasitism. Its activation is mediated by the NF?B transcription factor " Dorsal-related Immunity Factor " (Dif), which is required in the PSC for rapid lamellocyte production and LG dispersion. Furthermore, I established the existence of a genetic network comprising the Toll/NFkB and EGFR signalling pathways and Reactive Oxygen Species (ROS), in order to control the immune response to parasitism. An increase in ROS levels in the PSC and EGFR pathway activation in the immune cells, have been described as required for wasp egg encapsulation. My data suggest that the ROS and the EGFR pathway are also required for LG dispersion following wasp parasitism, in PSC cells and in hematopoietic progenitors, respectively. Based on the high conservation of signalling pathways and molecular processes controlling hematopoiesis, my results raise the question of whether such a network is conserved in the mammalian hematopoietic niche in response to pathogenic infections
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36

Morais, Drausio Honorio [UNESP]. "Aspectos ecológicos da helintofauna de anfíbios Leptodactylidae (ANURA) no Estado do Mato Grosso, Brasil." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/106504.

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Nos necropsiamos 668 espécimes de 21 espécies de rãs da família Leptodactylidae colecionadas entre os anos de 1987 e 2010, provenientes de 36 municípios, distribuídos por quatro regiões: Amazônia, Cerrado, Pantanal e áreas de transição de Cerrado e Amazônia no Estado do Mato Grosso, Brasil. 535 anfíbios estavam parasitados e destes, recuperamos 31.580 helmintos representados por 38 espécies, distribuídos em Nemátoda, Tremátodas (Digenéticos e Monogenéticos), Cestoda e Acantocephala. Os padrões de infecção foram estimados através da prevalência, abundância média e intensidade de infecção. A hierarquia dos termos foram de comunidades parasitárias, que inclui infrapopulações, infracomunidade, comunidade componente e supracomunidade. As espécies de helmintos foram classificadas como centrais, secundárias e satélite de acordo com suas prevalências. Para análises das diferenças entre as abundancias médias nas quatro diferentes regiões foram realizados testes de Kruskal-Wallis para cada uma das três espécies de hospedeiros que ocorreram em todas as regiões, em seguida foram feitas comparações através do método de Dunn para verificar qual seria a diferença. A análise de similaridade entre as supracomunidades foi feita pela a presença e ausência das espécies parasitas presentes em cada região estudada e calculada pelo índice qualitativo de Jaccard e elaborado um Dendrograma de similaridade. O helminto mais comum nas populações de anfíbios foram os cosmocercídeos, seguido por Oswaldocruzia sp. e Physaloptera sp, S. formosula, O. lopesi, Brevimulticaecum sp e M. monas. Oswaldocruzia sp., Physaloptera sp, S. formosula e os cosmocercídeos foram os parasitas com maior número de hospedeiros compartilhados, ou seja, seis espécies de hospedeiros. Os cosmocercídeos foram os helmintos com as maiores prevalências infectando as populações de sete hospedeiros e...
We necropsied 668 specimens of 21 frog species belonging to Leptodactylidae family, sampled from the year of 1987 to 2010, from 36 municipalities, distributed in four regions: Rainforest, Savannah, Wetland and transitional areas between Savannah and Rainforest in Mato Grosso State, Brazil. 535 amphibians were parasitized and we recuperated 31,580 helminths represented by 38 species, distributed in Nematode, Trematode (Digenean and Monogenean), Cestode and Acanthocephala.. The infection patterns were estimated through prevalence, mean abundance and intensity of infection. The hierarchy of the terms was parasite communities, including infrapopulations, infracommunity, component community and supracommunity. The helminth species were classified as core, secondary, and satellite according to their prevalence. Kruskal-Wallis test was used to analyze the difference between mean abundances for the four different regions for each one of the three host species that occurred in all regions. Afterwards it was carried out comparisons using the Dunn method to verify what difference would be. The analysis of similarity among supracommunities was made using the presence and absence of parasite species present in each studied region calculated by Jaccard qualitative index and a Dendrogram of similarity was elaborated. The most commom helminth in the amphibian populations was cosmocercidae, followed by Oswaldocruzia sp. and Physaloptera sp, S. formosula, O. lopesi, Brevimulticaecum sp and M. monas. Oswaldocruzia sp., Physaloptera sp, S. formosula and the cosmocercidae were the parasites with greater number of shared hosts, with six host species. The cosmocercidae were the helminthes with the highest prevalence, infecting seven host populations, and less common in eight ones. Other species considered as secondary were Physaloptera sp. larva, the Trematode M. monas and the Nematodes S. brasili, O. mazzai and Oswaldocruzia sp. The leptodactilidae ...
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37

Morais, Drausio Honorio. "Aspectos ecológicos da helintofauna de anfíbios Leptodactylidae (ANURA) no Estado do Mato Grosso, Brasil /." Botucatu, 2013. http://hdl.handle.net/11449/106504.

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Orientador: Reinaldo José da Silva
Coorientador: Luciano Alves dos Anjos
Banca: Robson W. Ávila
Banca: Heleno Brandão
Banca: Mariluce G. Fonseca
Banca: Lúcia Helena O'Dwyer
Resumo: Nos necropsiamos 668 espécimes de 21 espécies de rãs da família Leptodactylidae colecionadas entre os anos de 1987 e 2010, provenientes de 36 municípios, distribuídos por quatro regiões: Amazônia, Cerrado, Pantanal e áreas de transição de Cerrado e Amazônia no Estado do Mato Grosso, Brasil. 535 anfíbios estavam parasitados e destes, recuperamos 31.580 helmintos representados por 38 espécies, distribuídos em Nemátoda, Tremátodas (Digenéticos e Monogenéticos), Cestoda e Acantocephala. Os padrões de infecção foram estimados através da prevalência, abundância média e intensidade de infecção. A hierarquia dos termos foram de comunidades parasitárias, que inclui infrapopulações, infracomunidade, comunidade componente e supracomunidade. As espécies de helmintos foram classificadas como centrais, secundárias e satélite de acordo com suas prevalências. Para análises das diferenças entre as abundancias médias nas quatro diferentes regiões foram realizados testes de Kruskal-Wallis para cada uma das três espécies de hospedeiros que ocorreram em todas as regiões, em seguida foram feitas comparações através do método de Dunn para verificar qual seria a diferença. A análise de similaridade entre as supracomunidades foi feita pela a presença e ausência das espécies parasitas presentes em cada região estudada e calculada pelo índice qualitativo de Jaccard e elaborado um Dendrograma de similaridade. O helminto mais comum nas populações de anfíbios foram os cosmocercídeos, seguido por Oswaldocruzia sp. e Physaloptera sp, S. formosula, O. lopesi, Brevimulticaecum sp e M. monas. Oswaldocruzia sp., Physaloptera sp, S. formosula e os cosmocercídeos foram os parasitas com maior número de hospedeiros compartilhados, ou seja, seis espécies de hospedeiros. Os cosmocercídeos foram os helmintos com as maiores prevalências infectando as populações de sete hospedeiros e ...
Abstract: We necropsied 668 specimens of 21 frog species belonging to Leptodactylidae family, sampled from the year of 1987 to 2010, from 36 municipalities, distributed in four regions: Rainforest, Savannah, Wetland and transitional areas between Savannah and Rainforest in Mato Grosso State, Brazil. 535 amphibians were parasitized and we recuperated 31,580 helminths represented by 38 species, distributed in Nematode, Trematode (Digenean and Monogenean), Cestode and Acanthocephala.. The infection patterns were estimated through prevalence, mean abundance and intensity of infection. The hierarchy of the terms was parasite communities, including infrapopulations, infracommunity, component community and supracommunity. The helminth species were classified as core, secondary, and satellite according to their prevalence. Kruskal-Wallis test was used to analyze the difference between mean abundances for the four different regions for each one of the three host species that occurred in all regions. Afterwards it was carried out comparisons using the Dunn method to verify what difference would be. The analysis of similarity among supracommunities was made using the presence and absence of parasite species present in each studied region calculated by Jaccard qualitative index and a Dendrogram of similarity was elaborated. The most commom helminth in the amphibian populations was cosmocercidae, followed by Oswaldocruzia sp. and Physaloptera sp, S. formosula, O. lopesi, Brevimulticaecum sp and M. monas. Oswaldocruzia sp., Physaloptera sp, S. formosula and the cosmocercidae were the parasites with greater number of shared hosts, with six host species. The cosmocercidae were the helminthes with the highest prevalence, infecting seven host populations, and less common in eight ones. Other species considered as secondary were Physaloptera sp. larva, the Trematode M. monas and the Nematodes S. brasili, O. mazzai and Oswaldocruzia sp. The leptodactilidae ...
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Dias, Karina Gabriele Alves. "Monogenéticos parasitos de peixes da ordem Characiformes provenientes do rio Batalha, médio rio Tietê, São Paulo, Brasil." Botucatu, 2017. http://hdl.handle.net/11449/150395.

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Orientador: Vanessa Doro Abdallah Kozlowiski
Resumo: Global biodiversity has been very discussed and some authors have argued of the species of parasites as a fundamental part of this. Thus the aim of the study was to obtain a better understanding of the monogeneans biodiversity of four fish species: Cyphocharax modestus (Fernández-Yépez, 1948), Moenkhausia intermedia (Eigenmann, 1908), Serrasalmus maculatus (Kner, 1858) and Roeboides descalvadensis (Fowler, 1932) from Batalha River, São Paulo State, Brazil. During the period from November 2014 to December 2014, four collections were carried out and with 120 fish caught (30 of each species). Nine species of dactylogirids were found: Curvianchorathus singularis, Dactylogyridae gen. sp., Calpidothecium sp., Palombitrema triangulum, Jainus hexops, Jainus amazonesis, Rhinoxenus piranhus, Anacanthorus sciponophallus and Notozothecium minor. In relation to the species C. modestus, 33% of the specimens were parasitized by monogenetics, being the species: C. sigularis (Prevalence - P = 23.33%, mean intensity - I = 4.14±0.5 and mean abundance - A = 0.97±0.4), P. triangulum (P = 17%, I = 4±0.4, A = 0.67±0.3), Dactylogyridae gen. sp. (P = 3%, I = 1, A = 0.03±0.5) and Calpidothecium sp. (P = 3%, I = 2, A = 0.07±0.4). S. maculatus presented a total prevalence of parasitism by monogenetic species of 87%. The species were: A. sciponophallus (P = 73.33%, I = 22±4.47, A = 16.13±4.0), R. piranhus (P = 70%, I = 5.81±0.94, A = 4.07±0.9) and N. minor (P = 30%, I = 7±1.58, A = 2.1±1.02). M. intermed... (Resumo completo, clicar acesso eletrônico abaixo)
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39

Silva, Lidiane Aparecida Firmino da. "Helmintos parasitas de Ameivula pyrrhogularis (Squamata Teiidae) na caatinga, Brasil /." Botucatu, 2018. http://hdl.handle.net/11449/153498.

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Orientador: Robson Waldemar Ávila
Resumo: A Caatinga é um ecossistema a ser investigado, pois apresenta distintos ambientes e uma fauna endêmica de lagartos. Ameivula pyrrhogularis é um teídeo encontrado no Nordeste, na zona de transição entre Caatinga, Cerrado e floresta estacional decidual e, até o presente momento, nenhum estudo parasitológico foi conduzido para esta espécie. A presente pesquisa teve como objetivo registrar o parasitismo em A. pyrrhogularis procedentes de quatro áreas do Ceará. É apresentado um inventário das espécies de helmintos, o qual foi constituído de nove taxa: Oochoristica travassosi (Cestoda), cistacantos (Acanthocephala), larvas de nematoide não identificadas, Cruzia sp., Oswaldofilaria sp., Physaloptera sp. e espécimes adultos de Parapharyngodon sp., Pharyngodon cesarpintoi e Physalopteroides venancioi (Nematoda). Para estes parasitas, foram verificados os parâmetros de infecção, trazendo a informação dos hospedeiros em que estas espécies já foram registradas. Foi observado que fatores biológicos (ontogenia, tamanho e sexo) do hospedeiro não influenciaram a abundância parasitária, mas significativas diferenças foram constadas de acordo com as estações e localidade analisadas, sendo que as maiores abundâncias de parasitas foram registradas em período de estiagem e em área conservada, indicando que os helmintos podem ser favorecidos em seus ciclos biológicos pela condição ambiental. Foi caracterizada a dieta de A. pyrrhogularis e demonstrado que a mesma sofre influencia espacial, o que re... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Caatinga is a Brazilian ecosystem still to be investigated due to its different environments and an endemic fauna of lizards. Ameivula pyrrhogularis belongs to the Teiidae and is found in the Northeast of Brazil, in the transition area between Caatinga, Cerrado, and temporary deciduous forest. To date, any parasitological study has been performed for this species. This research aimed to record the parasitism in A. pyrrhogularis from four areas of Ceará State, Brazil. An inventory of the helminth species is presented, which was composed by nine taxa: Oochoristica travassosi (Cestoda), cystacanths (Acanthocephala), larvae of unidentified nematode, Cruzia sp., Oswaldofilaria sp., Physaloptera sp., and adult specimens of Parapharyngodon sp., Pharyngodon cesarpintoi, and Physalopteroides venancioi (Nematoda). Infection parameters were verified for these parasites, bringing information on the hosts in which these species have already been registered. It was observed that biological factors (ontogeny, size, and sex) of the hosts did not influence the parasite abundance, but significant differences were recorded according to stations and locations, with the greatest parasite abundance reported in the dry season, indicating that the helminths can be favored in their biological cycles by environmental conditions. The diet of A. pyrrhogularis was characterized and showed that it is spatially influenced, which reflects the availability of prey. Moreover, it is suggested that food ite... (Complete abstract click electronic access below)
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40

Raczkowski, Joseph Martin. "Phylogeny and founding stage of Lasius (Acanthomyops) (Hymenoptera: Formicidae)." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1221749471.

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Mico, Michelle A. "Yellow warbler nests, structure, building materials and cowbird parasitism." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32191.pdf.

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42

Lockhart, Susanne J. "Molecular evolution, phylogenetics, and parasitism in Antarctic cidaroid echinoids /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2006. http://uclibs.org/PID/11984.

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43

Gerrelli, Dianne. "Studies on the pathogenicity of nematode parasitism in cattle." Thesis, Royal Veterinary College (University of London), 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518000.

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44

Evans, C. A. W. "Nramp1 genotype, stress and the immunopathogenesis of intracellular parasitism." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598898.

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The natural resistance associated macrophage protein gene (Nramp1) influences susceptibility to several intracellular infections. To investigate the mechanism of this effect, congenic Nramp1 wild type (infection resistant) and mutant (infection susceptible) mice were infected with Leishmania donovani. The Nramp1 mutant mice developed more severe infection. Quantitative RT-PCR and fluorescence microscopy demonstrated that the mutant mice had attenuated hepatic chemokine and pro-inflammatory cytokine innate immune responses, reduced hepatic cellular infiltrate, reduced hepatic apoptosis and abnormal accumulation of cellular iron. This validated methodology was used to investigate the function of Nramp1 in cerebral infection. Following Toxoplasma gondii infection, mutant mice had significantly greater mortality. Laboratory analysis demonstrated for the first time that the naturally occurring infection-susceptible mutation in Nramp1 attenuates brain expression of chemokines, pro-inflammatory and immuno-regulatory cytokines in response to infection. During this research, it was noted that Nramp1 genotype also affected the behavioural stress response and this was investigated using restraint stress and quantitative in situ hybridisation. Compared with wild type mice, Nramp1 mutant mice had larger adrenal glands and higher circulating corticosterone concentrations but their hypothalamic, adrenal and behavioural stress responses following restraint stress were reduced. This abnormal stress response in Nramp1 mutant mice was associated with restraint stress increasing susceptibility to T. gondii infection in aged but not young mice. Immunochemical studies suggested that the Nramp1 protein was expressed on cerebral neurones as well as cells of the monocyte/macrophage lineage.
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45

Hume, K. D. "Sexual selection, pairing patterns and parasitism in freshwater amphipods." Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268447.

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46

Partington, Elizabeth Claire. "Influence of nutrition on parasitism in periparturient dairy ewes." Thesis, Open University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418468.

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47

Reynolds, Michael. "Behavioural responses of fish to parasitism and environmental conditions." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/108207/.

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Every aspect of an individual’s behaviour is, to some extent, mediated by parasite exposure. Potential hosts can, for example, initiate evasive behaviours towards infected conspecifics to reduce infection risk. If infected, individuals may exhibit adaptive behavioural responses aimed at reducing pathological symptoms. In addition to infection-mediated behavioural modifications, hosts behaviourally adapt to the environment in which they reside. Disentangling the effects of parasitism from environmental variables on host behaviour can be challenging. In a series of self-contained experiments, this thesis investigates three research areas. Firstly, how thermal and hydrological environmental conditions impact freshwater host-parasite interactions; secondly, how parasite infections mediate host behavioural modifications; and finally, how such behavioural changes have population level effects with respect to social structuring. The first experiment in this thesis describes how, when presented with a range of thermal conditions, Trinidadian guppies, Poecilia reticulata Peters 1859, infected with a common monogenean ectoparasite, Gyrodactylus turnbulli Harris 1986, frequent warmer thermal conditions to self-medicate against infection (Chapter 2). In a second experiment, G. turnbulli infected guppies experiencing dissimilar flow conditions showed a significant decrease in shoaling tendencies; but only in the absence of flowing water (Chapter 3). During this experiment, infected fish were observed increasing body contact with conspecifics: a behavioural adaptation presumably aimed at offloading parasite burdens (investigated in Chapter 4). Furthermore, infected hosts exhibited nocturnal restlessness, which may have further repercussions for host health (Chapter 5). Finally, parasite-mediated host behavioural modifications had significant population level effects with respect to social structuring. G. turnbulli infected guppies significantly increased their social rank within a population and instigated more contacts than they received, in contrast to their uninfected counterparts (Chapter 6). The infection status of an individual therefore determines its significance in mediating a population’s social dynamics, and so driving disease transmission processes.
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48

Farrar, Lyndsey. "Characterizing Traces of Predation and Parasitism on Fossil Echinoids." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1556793580479455.

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49

Jajszczok, Justyna. "The parasite and parasitism in victorian science and literature." Doctoral thesis, Katowice : Uniwersytet Śląski, 2017. http://hdl.handle.net/20.500.12128/676.

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Celem rozprawy Pasożyt i pasożytnictwo w wiktoriańskiej nauce i literaturze jest ukazanie, w jaki sposób nauka (rozumiana tu jako nauka biologiczna) i literatura (w rozumieniu prozy) okresu wiktoriańskiego wzajemnie na siebie wpływały. Te powiązania są analizowane na przykładzie pasożyta i pasożytnictwa, które to zjawiska rozpatrywane są na czterech płaszczyznach: biologicznej, ekologicznej, zwyczajowej i literackiej. Zawarte w rozprawie teksty literackie i naukowe traktowane są równorzędnie: jako fikcyjne i niefikcyjne opowieści (stories). Rozdział I ukazuje, jak zależności pomiędzy nauką a literaturą można interpretować za pomocą ekologicznych interakcji, od neutralizmu do mutualizmu, na przykładach dzieł kilku wiktoriańskich pisarzy (Alfred, Lord Tennyson, Karol Dickens, H. G. Wells) oraz naukowców (Karol Darwin, Alfred Russel Wallace, George Lyell, Robert Chambers, E. Ray Lankester). Mutualizm jest tu wykorzystany do analizy analogii pomiędzy powieścią Miasteczko Middlemarch George Eliot a pismami G. H. Lewesa, w których pewne pojęcia używane przez jednego z autorów są pożyczane, adaptowane i zmieniane przez drugiego, by później pojawić się na nowo w twórczości pierwszego twórcy. Opierając się na idei mutualizmu naukowo-literackiego, Rozdział II ukazuje paradoksy związane z pasożytami, zaczynając od skomplikowanej etymologii samego słowa „pasożyt”. W pierwotnym greckim znaczeniu termin ten (parasitos) łączył w sobie znaczenia, które dziś pojawiają się na płaszczyźnie biologicznej, ekologicznej i zwyczajowej, co zaprezentowane jest w rozdziale na przykładach naukowych opisów różnych gatunków pasożytów oraz literackich postaci Chrześcijańskich Zwierząt Mięsożernych (Christian Carnivora) pojawiających się w Miasteczku Middlemarch, a także członków rodziny Dedlock i Harolda Skimpole’a z Samotni Karola Dickensa. Celem Rozdziałów III i IV jest zaprezentowanie dwóch historii pochodzenia pasożytów; jako wywodzących się z wnętrza ciała żywiciela oraz jako pochodzących z zewnątrz. W Rozdziale III ukazane są wczesne teorie europejskich naukowców (przede wszystkim teoria samorództwa) oraz popularne wierzenia ludzi spoza kręgów zachodnich, według których pasożyty generowane były wewnątrz swoich żywicieli i co za tym idzie, uznawane były albo za objawy braku wewnętrznej równowagi żywiciela, albo jako przyczyny tej nierównowagi. Koncepcji tej użyto w tym rozdziale do zinterpretowania dwóch powieści: miejska biedota z Dickensowskiej Samotni odczytana zostaje tu jako wytworzona z rozkładającej się materii londyńskich slumsów, natomiast panowie Bulstrode i Raffles z Miasteczka Middlemarch – jako przychodzący z zewnątrz obcy burzący równowagę lokalnej społeczności. Alternatywna teoria pochodzenia pasożytów jest tematem Rozdziału IV, który wprowadza pojęcie literatury infekcji – jako podgatunku literatury inwazji (invasion literature). Czerpiąc zarówno z bakteriologii jak i medycyny tropikalnej, literatura ta prezentuje wizje, w których wrażliwa tkanka imperium brytyjskiego zostaje zaatakowana przez zjadliwe, egzotyczne czynniki patogenne. Jako przykład literatury infekcji, której antagoniści interpretowani są jako nosiciel i patogen użyta jest tu powieść Znak czterech Arthura Conan Doyle’a. Innym przykładem literatury infekcji jest analizowana w Rozdziale V powieść Richarda Marsha Skarabeusz Izydy (The Beetle), która ukazuje atak pojedynczego, ale niezwykle wirulentnego, egipskiego najeźdźcy. Rozdział zawiera dwie opowieści o infekcji; jedną zgodną z dziewiętnastowiecznymi normami i stereotypami, i drugą kwestionującą te normy. W dalszej części rozdziału zawarte są przykłady na analogiczne zachowania, które przejawiają zarówno antagonista z powieści, jak i pasożyty obserwowane w naturze. Aby wyjaśnić te analogie, wprowadzono tu wywodzące się z nauk ewolucyjnych pojęcie konwergencji, tj. procesu, w którym odrębne gatunki biologiczne wykształcają analogiczne cechy funkcjonalne. Ostatni rozdział rozwija ideę konwergencji w literaturze i nauce na podstawie dwóch koncepcji wywodzących się z prozy wiktoriańskiej, które później odnajdują się w studiach parazytologicznych. Naukowa hipoteza Czerwonej Królowej odczytana jest jako nowa wersja idei, które pierwotnie znalazły się w Po drugiej stronie lustra Lewisa Carrolla, natomiast przykłady zawarte w teorii unikania pasożytów (Parasite Avoidance Theory) Valerie Curtis są odnajdywane w następujących wiktoriańskich powieściach: Samotni, Miasteczku Middlemarch, Znaku czterech i Skarabeuszu Izydy.
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50

Möst, Thomas. "Salmonella virulence factors and their role in intracellular parasitism." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4046/document.

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Salmonella est un pathogène intracellulaire dont la virulence dépend de la fonction de deux systèmes de sécrétion du type trois (T3SS). Les T3SSs sont responsables pour la transduction de protéines effectrices dans le cytoplasme de la cellule hôte afin d'initier l'invasion de la cellule et de former la vie intracellulaire de Salmonella. Plusieurs effecteurs forment la SCV et induisent un réseau de tubules qui est impliqué dans la stabilisation de la SCV. Il consiste de trois différents genres de tubules. Nous avons pu montrer que les protéines effectrices SseF et SseG sont responsables pour la formation d'un genre de ces tubules, les LAMP-1 negative tubules (LNTs). Leur fonction est importante puisque des souches de Salmonella qui induisent que des LNTs et ne pas d'autres tubules sont apte de créer une SCV stable. Ceci améliore la réplication et virulence in vivo comparé à des souches qui ne peuvent pas induire des tubules. En utilisant les LNTs comme modèle, nous avons essayé de comprendre la contribution des tubules à la formation de la SCV et aussi leurs interaction avec les endosomes tardives et les lysosomes (LE/lys). Nous avons découvert une contribution essentielle de la petite GTPase Arl8B à la fusion de tubules avec les LE/lys. Ainsi, le knockdown d'Arl8B réduit la capacité de reproduction de Salmonella dans la cellule hôte. Nous avons pu démontrer qu'une interaction entre l'effecteur SifA et Arl8B est responsable pour ces observations
Salmonella is an intracellular pathogen, whose virulence relies on the function of two type three secretion systems (T3SSs). The T3SSs are responsible for the delivery of effector proteins into the host cell cytoplasm in order to mediate invasion of the cell and to shape Salmonella's intracellular life.Salmonella's intracellular survival and replication depends on its niche, the Salmonella containing vacuole (SCV), a compartment that is derived from host plasma membrane. Several effectors shape the SCV and give rise to a tubular network, which is implicated in the SCV's stabilization and consists of three different kinds of tubules. We were able to show that the effector proteins SseF and SseG play in concert to form one kind of tubules, the recently discovered LAMP-1-negative tubules (LNTs). Their function is important to Salmonella, as strains having only LNTs but none of the other tubules are able to create a stable SCV, which leads to better replication and virulence in vivo compared to a strain that lacks in tubule formation. Starting from these LNTs as working model, we tried to understand the contribution of tubules to the formation of the SCV and their interactions with the late endosomal / lysosomal compartment (LE/lys). We deciphered the small GTPase Arl8B to play an essential role in the fusion of tubules with LE/lys. Thereby, the knockdown of Arl8B reduced Salmonella's capability to replicate within host cells. We were able to show that an interaction between the effector SifA and Arl8B was responsible for our observations
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