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V G Davydov - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural investigation of the secondary excretory system in different stages of the Procercoid of Triaenophorus nodulosus (Cestoda, Pseudophyllidea, Triaenophoridae).
Parasitology, 1998Co-Authors: J V Korneva, B I Kuperman, V G DavydovAbstract:The formation of the definitive Procercoid excretory system of the pseudophyllidean cestode Triaenophorus nodulosus has been investigated. This process can be divided into 3 main stages. In the first stage, active autophagic processes lead to the formation of intracellular excretory canals. In the second stage, the process of the autolysis is enhanced and the system of intercellular lacunae functioning as an excretory system is formed. A definitive excretory system of the Procercoid forms at the next stage, by means of the migration and proliferation of undifferentiated cells replacing the lacunar system.
J V Korneva - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructural investigation of the secondary excretory system in different stages of the Procercoid of Triaenophorus nodulosus (Cestoda, Pseudophyllidea, Triaenophoridae).
Parasitology, 1998Co-Authors: J V Korneva, B I Kuperman, V G DavydovAbstract:The formation of the definitive Procercoid excretory system of the pseudophyllidean cestode Triaenophorus nodulosus has been investigated. This process can be divided into 3 main stages. In the first stage, active autophagic processes lead to the formation of intracellular excretory canals. In the second stage, the process of the autolysis is enhanced and the system of intercellular lacunae functioning as an excretory system is formed. A definitive excretory system of the Procercoid forms at the next stage, by means of the migration and proliferation of undifferentiated cells replacing the lacunar system.
Boeger, Walter Antonio Pereira - One of the best experts on this subject based on the ideXlab platform.
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Cestodes larvaires (Platyhelminthes, Cestoda) de poisson Sciaenidae de la côte sud du Brésil.
2005Co-Authors: Pereira Junior Joaber, Boeger, Walter Antonio PereiraAbstract:Cestode larvae were collected from 10 species of sciaenid fishes from the coast of Rio Grande do Sul, Brazil. Eleven species of Trypanorhyncha and two unindentified larvae are reported: Pterobothrium heteracanthum, P. crassicolle, Callitetrarhynchus gracilis, C. speciosus, Dasyrhynchus pacificus, Heteronybelinia nipponica, H. annakohnae n. sp., H. estigmena, Nybelinia bisulcata, Progrillotia dollfusi, Dollfusiella sp., an unidentified species of plerocercoid larva, and an unidentified species of Procercoid larva. Heteronybelinia annakohnae n. sp. is described based on specimens from four host species. It is characterized by a long pars postbulbosa and by bothridial margins covered with spines and that overlap the bulbs. Progrillotia dollfusi is redescribed based on paratypes and specimens collected in the present study. The basal tentacular armature, the presence of a prebulbar organ and of a pars postbulbosa, the attachment of the retractor muscle of the tentacle in the first third of the bulb, and the pres- ence of gland cells in the interior of the bulbs, are reported in this species for the first time. These characteristics support and amend the diagnosis of Progrillotia. A Procercoid larva is described for the first time from fish in Brazil. Measurements, descriptions, and drawings of the specimens of those species which are insufficiently or incompletely known are presented.Des larves de cestodes ont été collectées chez 10 espèces de poissons sciaenidés provenant de la côte de Rio Grande do Sul, Brésil. Onze espèces de trypano-rhynques et deux larves non identifiées sont signalées : Pterobothrium heteracan-thum, P.crassicolle, Callitetrarhynchus gracilis, C. speciosus, Dasyrhynchus pacificus, Heteronybelinia nipponica, H. annakohnae n. sp., H. estigmena, Nybelinia bisulcata, Progrillotia dollfusi, Dollfusiella sp., une espèce non identifiée de larve plerocer-coïde ainsi qu’une espèce indéterminée de larve procercoïde. Heteronybelinia annakohnae n. sp. est décrit sur la base de spécimens collectés chez quatre espèces d’hôtes. Ce cestode est caractérisé par une longue pars postbulbosa et par les marges des bothridies qui sont couvertes d’épines et qui chevauchent le bulbe. Progrillotia dollfusi est redécrit sur la base des paratypes et des spécimens collectés lors de cette étude. L’armature tentaculaire de base, la présence d’un organe pré-bulbaire et de la pars postbulbosa, l’attachement du muscle rétracteur du tenta-cule au niveau du premier tiers du bulbe et la présence de glandes cellulaires à l’intérieur des bulbes sont observées pour la première fois chez cette espèce. Ces caractéristiques soutiennent et modifient la diagnose de Progrillotia. Une larve procercoïde est décrite pour la première fois chez un poisson brésilien. Les mesures, descriptions et dessins des spécimens de cette espèce, qui sont insuffi-samment ou incomplètement connues, sont présentés dans ce travail
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Larval tapeworms (Platyhelminthes, Cestoda) from sciaenid fishes of the southern coast of Brazil
2005Co-Authors: Pereira Junior Joaber, Boeger, Walter Antonio PereiraAbstract:Cestode larvae were collected from 10 species of sciaenid fishes from the coast of Rio Grande do Sul, Brazil. Eleven species of Trypanorhyncha and two unindentified larvae are reported: Pterobothrium heteracanthum, P. crassicolle, Callitetrarhynchus gracilis, C. speciosus, Dasyrhynchus pacificus, Heteronybelinia nipponica, H. annakohnae n. sp., H. estigmena, Nybelinia bisulcata, Progrillotia dollfusi, Dollfusiella sp., an unidentified species of plerocercoid larva, and an unidentified species of Procercoid larva. Heteronybelinia annakohnae n. sp. is described based on specimens from four host species. It is characterized by a long pars postbulbosa and by bothridial margins covered with spines and that overlap the bulbs. Progrillotia dollfusi is redescribed based on paratypes and specimens collected in the present study. The basal tentacular armature, the presence of a prebulbar organ and of a pars postbulbosa, the attachment of the retractor muscle of the tentacle in the first third of the bulb, and the pres- ence of gland cells in the interior of the bulbs, are reported in this species for the first time. These characteristics support and amend the diagnosis of Progrillotia. A Procercoid larva is described for the first time from fish in Brazil. Measurements, descriptions, and drawings of the specimens of those species which are insufficiently or incompletely known are presented.Des larves de cestodes ont été collectées chez 10 espèces de poissons sciaenidés provenant de la côte de Rio Grande do Sul, Brésil. Onze espèces de trypano-rhynques et deux larves non identifiées sont signalées : Pterobothrium heteracan-thum, P.crassicolle, Callitetrarhynchus gracilis, C. speciosus, Dasyrhynchus pacificus, Heteronybelinia nipponica, H. annakohnae n. sp., H. estigmena, Nybelinia bisulcata, Progrillotia dollfusi, Dollfusiella sp., une espèce non identifiée de larve plerocer-coïde ainsi qu’une espèce indéterminée de larve procercoïde. Heteronybelinia annakohnae n. sp. est décrit sur la base de spécimens collectés chez quatre espèces d’hôtes. Ce cestode est caractérisé par une longue pars postbulbosa et par les marges des bothridies qui sont couvertes d’épines et qui chevauchent le bulbe. Progrillotia dollfusi est redécrit sur la base des paratypes et des spécimens collectés lors de cette étude. L’armature tentaculaire de base, la présence d’un organe pré-bulbaire et de la pars postbulbosa, l’attachement du muscle rétracteur du tenta-cule au niveau du premier tiers du bulbe et la présence de glandes cellulaires à l’intérieur des bulbes sont observées pour la première fois chez cette espèce. Ces caractéristiques soutiennent et modifient la diagnose de Progrillotia. Une larve procercoïde est décrite pour la première fois chez un poisson brésilien. Les mesures, descriptions et dessins des spécimens de cette espèce, qui sont insuffi-samment ou incomplètement connues, sont présentés dans ce travail
James C Chubb - One of the best experts on this subject based on the ideXlab platform.
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competitive growth strategies in intermediate hosts experimental tests of a parasite life history model using the cestode schistocephalus solidus
Evolutionary Ecology, 2006Co-Authors: Marilyn Michaud, G A Parker, James C ChubbAbstract:In parasites with a complex life cycle, the fitness of an individual depends on its probability of reaching the final host and on its fecundity. Because larval growth in intermediate hosts may affect both transmission and adult size, selection should optimize growth patterns that are conditional on the presence and number of conspecific competitors. A recent model predicts that the total parasite volume per host should increase with intensity if larvae are able to vary growth depending on the number of conspecifics in the host (Life History Strategy hypothesis, i.e. LHS). Further, we would here expect growth rates to increase with intensity. By contrast, under the simplest alternative hypothesis of Resource Constraints (i.e. RC), the total parasite volume should remain constant. We experimentally infected copepods Macrocyclops albidus with the cestode Schistocephalus solidus to achieve 1, 2 or 3 parasites per host taking care that hosts had similar quality status at each infection level, and compared larval growth trajectories at the three intensity levels. The asymptotic total parasite volume was larger in double and triple infections than in single infections. Furthermore, the asymptotic total parasite volume was significantly larger in triple than in double infections but only in larger copepods that were less constrained by a host-size ceiling effect. These results, together with the fact that growth rates increased with intensity, support the LHS hypothesis: Procercoids of a tapeworm may “count” their conspecific competitors in their first intermediate host to harvest its resources strategically until the next step in their complex life cycle.
Christopher J Secombes - One of the best experts on this subject based on the ideXlab platform.
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rainbow trout oncorhynchus mykiss walbaum 1792 leucocyte interactions with metacestode stages of diphyllobothrium dendriticum nitzsch 1824 cestoda pseudophyllidea
Fish & Shellfish Immunology, 1991Co-Authors: G J E Sharp, A W Pike, Christopher J SecombesAbstract:Procercoids of Diphyllobothrium dendriticum were incubated for 5 or 24 h with rainbow trout head kidney leucocyte suspension in vitro , in the absence or presence of complete and/or incomplete (heat inactivated) normal or specific immune serum. Neutrophils and macrophages were the predominant leucocytes that were found to adhere to the Procercoid tegument, although a third unidentified leucocyte type was also seen. Leucocyte adherence was considerably increased by the presence of immune serum, indicating a possible interaction between the non-specific and specific immune response in the host inflammatory reaction to this parasite. Indeed, it was only in the presence of immune serum that damage to the Procercoid tegument occurred. Production of both hydrogen peroxide and superoxide anion from macrophages was induced by antigen extracts from plerocercoids of D. dendriticum , prepared either by freezing and thawing specimens or by culturing live plerocercoids in vitro to obtain a conditioned medium. The possibility that reactive oxygen species contribute to the damage observed in the adherence assays is discussed.