RESUMO
Marmosa constantiae is a species of marsupial restricted to the central portion of South America. In Brazil, it occurs in the northwestern region including five states of the Amazon, Cerrado, and Pantanal biomes. However, there is no study of the helminth fauna or helminth community structure for this marsupial. The aims of this study were to describe the species composition and to analyse the structure of the helminthic community of M. constantiae in an area of the Amazon Arc in Sinop, north of the state of Mato Grosso, Brazil. Parasites were searched in 53 specimens of this marsupial, among which 44 were infected with at least one helminth species. Parasitic helminths were counted and identified. Nine species were collected: seven nematodes, one cestode, and one acanthocephalan. The most abundant species were Gracilioxyuris agilisis, Travassostrongylus scheibelorum, Pterygodermatites sinopiensis, and Subulura eliseae. These species were the only dominant ones in the component community. No significant differences were observed in the abundance and prevalence of helminths between male and female hosts. Host body size significantly influenced helminth abundance in males. The pattern of community structure considering the infracommunities in this locality indicated more species replacement than species loss along the environmental gradient. This is the first study to report the helminth fauna and the helminth community structure of M. constantiae.
Assuntos
Helmintíase Animal , Helmintos , Marsupiais , Feminino , Masculino , Camundongos , Animais , Brasil/epidemiologia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Gambás/parasitologiaRESUMO
Abstract A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.
Resumo Uma nova espécie de nematódeo da subfamília Pudicinae (Heligmosomoidea: Heligmonellidae) é descrito parasitando o intestino delgado de Proechimys simonsi (Rodentia: Echimyidae) em Nova Cintra, município de Rodrigues Alves, Estado do Acre, Brasil. O gênero Pudica inclui 15 espécies parasitas de roedores Neotropicais das famílias: Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae e Myocastoridae. Destas, quatro espécies de nematódeos foram encontradas parasitando três diferentes espécies do roedor Proechimys no bioma Amazônia. Pudica wandiquei n. sp. é diferente das outras espécies de Pudica pela distância entre os raios 6 e 8 e pelo tipo da bolsa caudal, que é 1-3-1 em ambos os lados.
Assuntos
Animais , Parasitos , Trichostrongyloidea , Nematoides , Roedores , BrasilRESUMO
A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.
Uma nova espécie de nematódeo da subfamília Pudicinae (Heligmosomoidea: Heligmonellidae) é descrito parasitando o intestino delgado de Proechimys simonsi (Rodentia: Echimyidae) em Nova Cintra, município de Rodrigues Alves, Estado do Acre, Brasil. O gênero Pudica inclui 15 espécies parasitas de roedores Neotropicais das famílias: Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae e Myocastoridae. Destas, quatro espécies de nematódeos foram encontradas parasitando três diferentes espécies do roedor Proechimys no bioma Amazônia. Pudica wandiquei n. sp. é diferente das outras espécies de Pudica pela distância entre os raios 6 e 8 e pelo tipo da bolsa caudal, que é 1-3-1 em ambos os lados.
Assuntos
Animais , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/veterinária , Nematoides/anatomia & histologia , Nematoides/classificação , Roedores/parasitologiaRESUMO
Abstract A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.
Resumo Uma nova espécie de nematódeo da subfamília Pudicinae (Heligmosomoidea: Heligmonellidae) é descrito parasitando o intestino delgado de Proechimys simonsi (Rodentia: Echimyidae) em Nova Cintra, município de Rodrigues Alves, Estado do Acre, Brasil. O gênero Pudica inclui 15 espécies parasitas de roedores Neotropicais das famílias: Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae e Myocastoridae. Destas, quatro espécies de nematódeos foram encontradas parasitando três diferentes espécies do roedor Proechimys no bioma Amazônia. Pudica wandiquei n. sp. é diferente das outras espécies de Pudica pela distância entre os raios 6 e 8 e pelo tipo da bolsa caudal, que é 1-3-1 em ambos os lados.
RESUMO
A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.
Assuntos
Nematoides , Parasitos , Trichostrongyloidea , Animais , Brasil , RoedoresRESUMO
Abstract Host infection by parasites is influenced by an array of factors, including host and environmental features. We investigated the relationship between host sex, body size and age, as well as seasonality on infection patterns by acanthocephalan in coatis (Procyonidae: Nasua nasua) and in crab-eating foxes (Canidae: Cerdocyon thous ) from the Brazilian Pantanal wetlands. Between 2006 and 2009, we collected faecal samples from these hosts and analyzed for the presence of acanthocephalan eggs. Prevalence, abundance and intensity of eggs of acanthocephalans were calculated. Egg abundance was analyzed using generalized linear models (GLM) with a negative binomial distribution and models were compared by Akaike criteria to verify the effect of biotic and abiotic factors. Prevalence of acanthocephalans was higher in the wet season in both host species but did not differ between host sexes; however, adult crab-eating foxes showed higher prevalence of acanthocephalan eggs than juveniles. In contrast, prevalence of acanthocephalan eggs found in coatis was higher in coati juveniles than in adults. Host age, season and maximum temperature were the top predictors of abundance of acanthocephalan eggs in crab-eating foxes whereas season and host sex were predictors of egg abundance in coatis. The importance of seasonality for abundance of acanthocephalan was clear for both host species. The influence of host-related attributes, however, varied by host species, with host gender and host age being important factors associated with prevalence and parasite loads.
Resumo A infecção de hospedeiro por parasitos é influenciada por uma série de fatores, incluindo características do hospedeiro e ambientais. Nós investigamos a relação entre sexo do hospedeiro, tamanho corporal e idade, bem como sazonalidade nos padrões de infecção por acantocéfalos em coatis (Procyonidae: Nasua nasua) e em cachorro-do-mato (Canidae: Cerdocyon thous ) do Pantanal brasileiro e quais fatores explicaram melhor a prevalência e a intensidade desses parasitos. Entre 2006 e 2009, coletamos amostras fecais desses hospedeiros e analisamos a presença de ovos de acantocéfalos. Prevalência, abundância e intensidade de ovos de acantócefálios foram calculados. A abundância de ovos foi analisada utilizando modelos lineares generalizados (GLM) com distribuição binomial negativa e os modelos foram comparados pelo critério de Akaike para verificar o efeito de fatores bióticos e abióticos. A prevalência de acantocéfalos foi maior na estação úmida em ambas as espécies de hospedeiros, mas não diferiu entre os sexos do hospedeiro; no entanto, os cachorros-do-mato adultos apresentaram maior prevalência de ovos de acantocéfalos do que em juvenis. Em contraste, a prevalência de ovos de acantocéfalos encontrados em coatis foi maior em juvenis do que em adultos. A idade do hospedeiro, a estação e a temperatura máxima foram os preditores de abundância de ovos de acantocéfalos em cachorro-do-mato, enquanto a estação e o sexo do hospedeiro foram preditores da abundância dos ovos do parasito em coatis. A importância da sazonalidade para a abundância do acantocéfalo foi clara para ambas as espécies hospedeiras. A influência dos atributos relacionados ao hospedeiro, no entanto, variou entre as espécies de hospedeiros, sendo o sexo e idade do hospedeiro fatores importantes associados à prevalência e às cargas parasitárias.
Assuntos
Animais , Masculino , Feminino , Procyonidae , Acantocéfalos/fisiologia , Raposas , Helmintíase Animal/epidemiologia , Estações do Ano , Brasil/epidemiologia , Prevalência , Densidade Demográfica , Helmintíase Animal/parasitologiaRESUMO
Host infection by parasites is influenced by an array of factors, including host and environmental features. We investigated the relationship between host sex, body size and age, as well as seasonality on infection patterns by acanthocephalan in coatis (Procyonidae: Nasua nasua) and in crab-eating foxes (Canidae: Cerdocyon thous ) from the Brazilian Pantanal wetlands. Between 2006 and 2009, we collected faecal samples from these hosts and analyzed for the presence of acanthocephalan eggs. Prevalence, abundance and intensity of eggs of acanthocephalans were calculated. Egg abundance was analyzed using generalized linear models (GLM) with a negative binomial distribution and models were compared by Akaike criteria to verify the effect of biotic and abiotic factors. Prevalence of acanthocephalans was higher in the wet season in both host species but did not differ between host sexes; however, adult crab-eating foxes showed higher prevalence of acanthocephalan eggs than juveniles. In contrast, prevalence of acanthocephalan eggs found in coatis was higher in coati juveniles than in adults. Host age, season and maximum temperature were the top predictors of abundance of acanthocephalan eggs in crab-eating foxes whereas season and host sex were predictors of egg abundance in coatis. The importance of seasonality for abundance of acanthocephalan was clear for both host species. The influence of host-related attributes, however, varied by host species, with host gender and host age being important factors associated with prevalence and parasite loads.
Assuntos
Acantocéfalos/fisiologia , Canidae/parasitologia , Helmintíase Animal/epidemiologia , Procyonidae , Animais , Brasil/epidemiologia , Feminino , Helmintíase Animal/parasitologia , Masculino , Densidade Demográfica , Prevalência , Procyonidae/parasitologia , Estações do AnoRESUMO
Abstract Host infection by parasites is influenced by an array of factors, including host and environmental features. We investigated the relationship between host sex, body size and age, as well as seasonality on infection patterns by acanthocephalan in coatis (Procyonidae: Nasua nasua) and in crab-eating foxes (Canidae: Cerdocyon thous ) from the Brazilian Pantanal wetlands. Between 2006 and 2009, we collected faecal samples from these hosts and analyzed for the presence of acanthocephalan eggs. Prevalence, abundance and intensity of eggs of acanthocephalans were calculated. Egg abundance was analyzed using generalized linear models (GLM) with a negative binomial distribution and models were compared by Akaike criteria to verify the effect of biotic and abiotic factors. Prevalence of acanthocephalans was higher in the wet season in both host species but did not differ between host sexes; however, adult crab-eating foxes showed higher prevalence of acanthocephalan eggs than juveniles. In contrast, prevalence of acanthocephalan eggs found in coatis was higher in coati juveniles than in adults. Host age, season and maximum temperature were the top predictors of abundance of acanthocephalan eggs in crab-eating foxes whereas season and host sex were predictors of egg abundance in coatis. The importance of seasonality for abundance of acanthocephalan was clear for both host species. The influence of host-related attributes, however, varied by host species, with host gender and host age being important factors associated with prevalence and parasite loads.
Resumo A infecção de hospedeiro por parasitos é influenciada por uma série de fatores, incluindo características do hospedeiro e ambientais. Nós investigamos a relação entre sexo do hospedeiro, tamanho corporal e idade, bem como sazonalidade nos padrões de infecção por acantocéfalos em coatis (Procyonidae: Nasua nasua) e em cachorro-do-mato (Canidae: Cerdocyon thous ) do Pantanal brasileiro e quais fatores explicaram melhor a prevalência e a intensidade desses parasitos. Entre 2006 e 2009, coletamos amostras fecais desses hospedeiros e analisamos a presença de ovos de acantocéfalos. Prevalência, abundância e intensidade de ovos de acantócefálios foram calculados. A abundância de ovos foi analisada utilizando modelos lineares generalizados (GLM) com distribuição binomial negativa e os modelos foram comparados pelo critério de Akaike para verificar o efeito de fatores bióticos e abióticos. A prevalência de acantocéfalos foi maior na estação úmida em ambas as espécies de hospedeiros, mas não diferiu entre os sexos do hospedeiro; no entanto, os cachorros-do-mato adultos apresentaram maior prevalência de ovos de acantocéfalos do que em juvenis. Em contraste, a prevalência de ovos de acantocéfalos encontrados em coatis foi maior em juvenis do que em adultos. A idade do hospedeiro, a estação e a temperatura máxima foram os preditores de abundância de ovos de acantocéfalos em cachorro-do-mato, enquanto a estação e o sexo do hospedeiro foram preditores da abundância dos ovos do parasito em coatis. A importância da sazonalidade para a abundância do acantocéfalo foi clara para ambas as espécies hospedeiras. A influência dos atributos relacionados ao hospedeiro, no entanto, variou entre as espécies de hospedeiros, sendo o sexo e idade do hospedeiro fatores importantes associados à prevalência e às cargas parasitárias.
RESUMO
The study of parasite body size is an important approach to understand the different patterns of helminth community structure, once it is usually analysed using only numerical descriptors which do not capture size heterogeneity among parasite species. In the present study, we compared the pattern in the helminth community of three sympatric wild rodent species Akodon cursor, A. montensis and Oligoryzomys nigripes using numerical abundance and biomass approaches. The cestode Rodentolepis akodontis was the worm with highest biomass in the three rodents. The trichostrongylid Stilestrongylus lanfrediae presented highest biomass in O. nigripes and represented 70% of the total numeric abundance of parasites. Interestingly, for Akodon spp. the species with more biomass represented less than 10% of the total numerical abundance. Parasites with the higher numeric abundance do not have the largest body size. Although the biomass pattern is different from numeric abundance, this difference does not influence in the helminth distribution community among the three sympatric hosts. The status change of a helminth species within the community due to its volumetric dominance might justify a new approach since parasites belonging to different taxa obtain resources from the host in different ways.
A utilização do tamanho do corpo do parasita é uma importante abordagem para compreender diferentes padrões na estrutura da comunidade helmíntica, uma vez que são utilizados apenas descritores numéricos que não necessariamente detectam a heterogeneidade no tamanho entre as espécies de parasitos. No presente estudo, comparou-se o padrão da comunidade helmíntica de três roedores silvestres simpátricos (Akodon cursor, A. montensise e Oligoryzomys nigripes), usando uma abordagem com abundância numérica e biomassa. O cestoide Rodentolepis akodontis foi o helminto com maior biomassa nos três roedores. O tricostrongilídeo Stilestrongylus lanfrediae apresentou uma alta biomassa em O. nigripes e representou 70% da abundância numérica total dos parasitas. Interessantemente, em Akodon spp., a espécie com maior biomassa, representou menos de 10% da abundância total. Parasitas com maior abundância numérica não foram aqueles com maior tamanho do corpo. Embora o padrão de biomassa determinado tenha sido diferente da abundância numérica, essa diferença não influenciou na distribuição das comunidades de helmintos nos três hospedeiros simpátricos. A mudança do status de uma espécie de helminto dentro da comunidade em função da sua dominância volumétrica pode justificar uma nova abordagem, uma vez que parasitas pertencentes a diferentes táxons podem obter recursos de seu hospedeiro de forma diferente.
Assuntos
Animais , Helmintíase Animal/parasitologia , Helmintos/classificação , Doenças dos Roedores/parasitologia , Roedores/parasitologia , Biomassa , Interações Hospedeiro-Parasita , Roedores/classificação , ÁrvoresRESUMO
The study of parasite body size is an important approach to understand the different patterns of helminth community structure, once it is usually analysed using only numerical descriptors which do not capture size heterogeneity among parasite species. In the present study, we compared the pattern in the helminth community of three sympatric wild rodent species Akodon cursor, A. montensis and Oligoryzomys nigripes using numerical abundance and biomass approaches. The cestode Rodentolepis akodontis was the worm with highest biomass in the three rodents. The trichostrongylid Stilestrongylus lanfrediae presented highest biomass in O. nigripes and represented 70% of the total numeric abundance of parasites. Interestingly, for Akodon spp. the species with more biomass represented less than 10% of the total numerical abundance. Parasites with the higher numeric abundance do not have the largest body size. Although the biomass pattern is different from numeric abundance, this difference does not influence in the helminth distribution community among the three sympatric hosts. The status change of a helminth species within the community due to its volumetric dominance might justify a new approach since parasites belonging to different taxa obtain resources from the host in different ways.
Assuntos
Helmintíase Animal/parasitologia , Helmintos/classificação , Doenças dos Roedores/parasitologia , Roedores/parasitologia , Animais , Biomassa , Interações Hospedeiro-Parasita , Roedores/classificação , ÁrvoresRESUMO
The physiological interaction between the digenean Echinostoma paraensei larvae and the intermediate snail host Lymnaea columella was studied. The carbohydrate content was significantly altered in the digestive gland tissue of snails, decreasing after 20 days postinfection. At the end of the prepatent period, the carbohydrate content was reduced by 60% when compared to uninfected snails. The total protein was reduced by 80.01% and 76.42% in the hemolymph and digestive gland, respectively. The end products resulting from nitrogen degradation were also analyzed. The urea was significantly increased in both the hemolymph and digestive gland. In the former, the highest concentration was detected at day 10 postinfection and then decreased until the end of the prepatent period. In digestive glands from infected snails, urea was significantly higher than in uninfected ones after 20 days. The uric acid content was reduced by 94.72% in the hemolymph and 43.75% in digestive glands after 10 days postinfection. The ammonia was undetectable under the experimental conditions employed.
Assuntos
Echinostoma/isolamento & purificação , Interações Hospedeiro-Parasita , Lymnaea/parasitologia , Amônia/análise , Animais , Carboidratos/análise , Sistema Digestório/química , Echinostoma/patogenicidade , Hemolinfa/química , Proteínas/análise , Fatores de Tempo , Ureia/análise , Ácido Úrico/análiseRESUMO
The biological behaviour and morphometric data from two allopatric isolates of Echinostoma paraensei (Rio Bonito - RB and Sumidouro - SU) collected from naturally infected Nectomys squamipes from two secluded Atlantic Forest fragments were studied. Mice that had been experimentally infected with ten encysted metacercariae of each isolate were monitored weekly in two trials to analyse worm burden and the kinetics of worm distribution along the intestine. The total number of uterine eggs, wet weights and measurements of the worms and body, acetabulum, testes and ovaries were also analysed. The RB isolate showed a higher worm burden, 7.7+/-0.8, and a longer life span, 16 weeks, compared to a worm burden of 5.8+/-1.1 and life span of 9 weeks for the SU isolate. Worms of the RB isolate were clustered in the duodenum and in the bile duct while the SU isolate worms were dispersed along the small intestine of infected mice. Both isolates developed similarly as regards morphometric data and wet weight, although the total number of uterine eggs was greater in RB. The degree of intraspecific variation observed in the worm distribution along the intestine, worm burden and life span raises questions regarding the use of these criteria for species differentiation. These findings suggest that variation in biological parameters found between the E. paraensei isolates could result from geographical isolation and, in particular, the environmental conditions of transmission. Further studies on E. paraensei polulations from different forest fragments will contribute towards an understanding of the speciation of this parasite.
Assuntos
Echinostoma/patogenicidade , Enteropatias Parasitárias/parasitologia , Doenças Parasitárias em Animais/parasitologia , Animais , Ductos Biliares/parasitologia , Brasil , Echinostoma/anatomia & histologia , Intestino Delgado/parasitologia , Estágios do Ciclo de Vida , Masculino , Camundongos , Camundongos Endogâmicos/parasitologia , Parasitologia/métodosRESUMO
Schistosomiasis is a health problem in Brazil and the role of rodents in maintaining the schistosome life-cycle requires further clarification. The influence of Schistosoma mansoni on a population of Nectomys squamipes was studied by capture-recapture (1st phase, from June 1991 to November 1995) and removal (2nd phase, from April 1997 to March 1999) studies at Sumidouro, Rio de Janeiro, Brazil. During both phases coproscopic examinations were performed. At the 2nd phase the rodents were perfused and worms were counted. The population dynamics of parasites was studied. During the 1st phase, female reproductive parameters, longevity, recruitment and survivorship rates and migration patterns were studied in relation to schistosome prevalence. Water contamination (source of miracidia), abundance intermediate host and rodent migration were related to prevalence. The N. squamipes population was not obviously influenced by the infection, as shown by the high number of reproductive infected females, high longevity of infected individuals and the absence of a relationship between recruitment or survivorship rates and the intensity of schistosome infection. The data indicate that N. squamipes can increase transmission of S. mansoni in endemic areas and carry it to non-infected areas. Furthermore, this rodent can be used as an indicator of a transmission focus.
Assuntos
Muridae/parasitologia , Doenças dos Roedores/parasitologia , Schistosoma mansoni/crescimento & desenvolvimento , Esquistossomose mansoni/veterinária , Animais , Brasil/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Masculino , Contagem de Ovos de Parasitas/veterinária , Dinâmica Populacional , Prevalência , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/transmissão , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/transmissão , Estações do Ano , Esgotos , Estatísticas não Paramétricas , Água/parasitologiaRESUMO
The aim of the present research was to evaluate the potential of Nectomys rattus, the "water rat", to develop Schistosoma mansoni infection. Comparison with N. squamipes was carried out. Both species of rodents were submitted to transcutaneous infection using different infective cercariae loads: 50, 100 or 500. N. rattus showed high susceptibility to S. mansoni, with an infection rate of 71%. Rodents were able to excrete viable eggs of S. mansoni in the faeces during all infection period. For both species, the small intestine, followed by the liver and the large intestine, presented the highest concentration of eggs among the surveyed organs. Infection caused no animal death. Moreover, N. rattus accomplished the parasite's life cycle, by infecting the snails Biomphalaria glabrata and later Mus musculus. These evidences indicate that both N. rattus, as for N. squamipes are potential reservoirs for schistosomiasis in Brazil. Considering the fact that N. rattus and N. squamipes exist in the same natural ecosystems of S. mansoni, we suggest that these rodents must be regarded as influential factors in epidemiology surveys.
Assuntos
Muridae/parasitologia , Esquistossomose mansoni , Animais , Brasil , Reservatórios de Doenças , Suscetibilidade a Doenças , Feminino , Interações Hospedeiro-Parasita , Masculino , Contagem de Ovos de Parasitas , RatosRESUMO
The effect of anesthetic drugs on the localization of adult worms in albino mice was compared. The animals with 56 days of infection were anesthetized with pentobarbital sodium, ether or chloroform. Perfusion was carried out immediately after, recovering the worms and classifying them in relation to their localization on the liver or portal vein and the mesenteric veins. Our results showed that pentobarbital sodium produced a greater displacement of the worms to the liver (89%) than ether (76%) and chloroform (34%) did, when compared to the control group (22%). The difference between pentobarbital sodium and ether was significant (p < 0.05). We suggest that anesthetic drugs may not be used in studies on the distribution of adult worms in several hosts.
Assuntos
Clorofórmio/farmacologia , Éter/farmacologia , Pentobarbital/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Fígado/parasitologia , Veias Mesentéricas/parasitologia , Camundongos , Veia Porta/parasitologiaRESUMO
Twenty specimens of Nectomys squamipes born in captivity, were infected with 500 cercariae by the transcutaneous route. Coprologic examinations were carried out from the 5th to 23rd week after infection. On the 7th, 8th, 12th, 16th, and 23rd weeks the animals were sacrificed and perfused. The oogram was performed in segments of the small intestine (proximal, medial and distal portions) and the large intestine. The average pre-patent period was of 42 days. The average number of eggs varied from 350 on the 6th week, to 800 on the 13th. From the 14th week on, the average number of eggs eliminated was lower than 50 per gram of feces. The recovery of worms kept steady on the 7th, 8th and 12th week (16.85%; 15.45% and 11.95%), decreasing to 7.70% on the 16th week and 8.45% on the 23rd week. The proportion of male/female worms was about the same on the first two weeks, but from the 12th week on, the proportion was: 1.4/1 on the 12th week; 2.5/1 on the 16th week and 1.8/1 on the 23rd week. These observations suggest that N. squamipes may be used as an experimental model for schistosomiasis mansoni, to which it develops resistance mechanism, useful for immunity studies.
Assuntos
Arvicolinae/parasitologia , Enteropatias Parasitárias/parasitologia , Esquistossomose mansoni/parasitologia , Animais , Arvicolinae/imunologia , Colo/parasitologia , Suscetibilidade a Doenças , Feminino , Enteropatias Parasitárias/imunologia , Intestino Delgado/imunologia , Intestino Delgado/parasitologia , Masculino , Contagem de Ovos de Parasitas , Esquistossomose mansoni/imunologiaRESUMO
A infeccao experimental do A. arviculoides atraves de diferentes vias de penetracao das cercarias de Schistosoma mansoni (transcutanea e subcutanea) foi estudada pela cinetica de eliminacao de ovos nas fezes, pela recuperacao dos vermes adultos (no sistema porta e nos vasos mesentericos) e pelo oograma quantitativo. Demonstrou-se que a infeccao do A. arviculoides assemelha-se a dos camundongos albinos que serviram de controle, quanto a eficacia das vias de penetracao, ao habitat dos vermes adultos e ao oograma. Esses resultados sugerem que se avaliem outros aspectos da relacao parasito-hospedeiro para que o A. arviculoides possa ser indicado como modelo experimental alternativo, nos estudos sobre a esquistossomose.
