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The Helminthological Collection of the Oswaldo Cruz Institute is the biggest in Latin America and it is among the largest collections at worldwide reference level, with around 40,000 sets of specimens and approximately one million individual specimens. It contains helminths parasites of vertebrate and invertebrate animals that form part of the fauna of Brazil and other countries. The samples comprise holotypes, paratypes and representative specimens of Platyhelminthes, Acanthocephala, Nematoda and other non-helminth phyla, such as Annelida and Arthropoda. Some of the samples preserved in liquid media were found to have dried out. This made it impossible to analyze these samples morphologically for taxonomic purposes. The aim of this study was to test techniques used for rehydration of the tegument of specimens that had been found to have dried out and present protocols for such techniques. A total of 528 specimens that either no longer were immersed in preservatives or had already dried out were analyzed: 96 digenetic trematodes, 45 cestodes, 22 acanthocephalans, 357 nematodes, four hirudineans and four pentastomid crustaceans. The technique of rehydration using only distilled water on the specimens proved to be efficient for recovering tegument malleability, for all samples analyzed in this present study.(AU)

A Coleção Helmintológica do Instituto Oswaldo Cruz é a maior da América Latina e está entre as maiores coleções de referência mundial, com cerca de 40.000 lotes e, aproximadamente, um milhão de espécimes. Seu acervo reúne helmintos parasitos de animais vertebrados e invertebrados da fauna brasileira e de outros países. Seus exemplares são holótipos, parátipos e espécimes representativos de parasitos, pertencentes aos filos Platyhelminthes, Acanthocephala, Nematoda e, ainda alguns espécimes não-helmintos, pertencentes aos filos Annelida e Arthropoda. Parte das amostras preservadas como material líquido foram encontradas dessecadas. Esta condição torna as amostras inviáveis para análise morfológica para propósitos taxonômicos. Portanto, o objetivo deste trabalho foi testar técnicas usadas na reidratação do tegumento dos espécimes que se encontram dessecados e apresentar seus protocolos. Foram analisados 528 lotes, cujos espécimes encontravam-se sem conservantes ou já dessecados: 96 trematodeos digenéticos, 45 cestoides, 22 acantocéfalos, 357 nematoides, quatro hirudíneos e quatro crustáceos pentastomídeos. A técnica de reidratação dos espécimes, utilizando-se apenas água destilada, mostrou-se eficiente na recuperação da maleabilidade tegumentar de todas as amostras trabalhadas no presente estudo.(AU)

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To monitor and evaluate potential risks to birds' health, invertebrate species that have been used as live food items had their body contents searched for endoparasites. The contents of approximately 10,000 invertebrates were analyzed. A principal component analysis was performed to study the relationship between the presence/absence of endoparasites and the characteristics of the invertebrates. In most of them, including the species preferred by birds such as caterpillars, waxworms, mealworms, most grasshoppers, and spiders, no organism was identified. Such findings suggest a low potential for parasite transmission associated with its consumption by birds. Although they had unknown or even unlikely implications for the birds' health, gregarines, oxyurides Leidynema sp., and digenetic trematodes Monolecithotrema sp. were found in samples from woodlice, cockroaches, and centipedes, respectively. The only avian parasites observed in this study were Heterakis gallinarum in samples from earthworms and Acuaria spiralis from woodlice. Suggestively, soil invertebrates showed a higher prevalence of endoparasites and may represent a higher potential risk in comparison to the other categories of invertebrates sampled herein. Detritivory and collected origin were also explanatory variables related to the presence of endoparasites in the current study.

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We investigated the seasonal and interannual changes in diversity, abundance, and prevalence of chaetognaths and their parasites collected monthly during 1996-1998 in the Mexican Central Pacific. We tested the hypothesis of a positive relationship between abundance and species richness of chaetognaths and their parasites, and investigated the influence of the 1997-1998 El Niño event on this host-parasite interaction. Of the 9 chaetognath species collected in the present study, only 7 were found to be parasitized. Of 78154 chaetognath specimens collected, 790 were parasitized (1% prevalence) with at least 1 type of epibiont (cysts, perhaps protists) and 6 types of endoparasites: protists (apicomplexans, dinoflagellates, and ciliates), digeneans, cestodes, acanthocephalans, nematodes, and other unidentified endoparasites. Cysts, digeneans, and cestodes were the most abundant parasites. Mean intensity ranged from 1-4 endoparasites and from 1-21 epibionts host-1. Zonosagitta bedoti and Flaccisagitta enflata were the most abundant chaetognath species and had the highest parasite diversity. Mesosagitta minima and Parasagitta euneritica had the highest parasite prevalence (>2%). A 2-way cluster analysis defined sampling month groups as before, during, and after the 1997-1998 El Niño. The highest abundances of chaetognaths and parasites were associated with a high thermal stratification index, salinity, and mixed layer depth. We conclude that there is a positive, non-linear correlation between the abundance of chaetognaths and their parasites. Although El Niño decreased the abundance and diversity of chaetognaths throughout the time series, the abundance and diversity of their parasites were not significantly different among hydro-climatic periods, suggesting that host abundance must decrease orders of magnitude to influence host availability for parasites.

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Peritrich ciliates of the genus Trichodina are internal or external symbionts of invertebrate and vertebrate hosts. We describe here Trichodina ctenophorii n. sp., a symbiont of Mnemiopsis mccraydii and Beroë ovata (Phylum Ctenophora). The morphology of fixed and living specimens is revealed by silver impregnation, scanning electron microscopy, and differential interference microscopy. Distinguishing features of Trichodina ctenophorii include a denticular morphology composed of falcate, blunt-tipped blades, and long, straight thorns, with five pins per denticle. Trichodina ctenophorii is found only on the comb plates of these ctenophores. To the best of our knowledge, this is the first report of a trichodinid from the Gulf of Mexico and the first associated with ctenophores.

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Three species of pelagic coelenterates and ctenophores captured in Mar del Plata port, Buenos Aires, Argentina, were examined for digenean parasites. Encysted metacercariae were observed and collected. Cysts were found in the mesoglea of the hydromedusae Phialidium sp. and Liriope tetraphylla, and in the ectenophore Mnemiopsis macradyi. The morphology of the worms resembles that of the lepocreadiid digeneans. This is the first record for a metacercaria encysted in hydromedusae or ctenophores.

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The present paper is review of the scientific literature over the most important sarcodimes (Protozoa: Amoebida) that have been found on the world in fish and acuatic invertebrates of commercial value. Special emphasis is given in this review to those sarcodines that cause disease.

El presente artículo es una revisión de la literatura científica sobre los principales sarcodinos (protozoa: Amoebida) que han sido hallados en el mundo en peces e invertebrados acuáticos de valor comercial. En esta revisión se da especial énfasis a aquellos sarcodinos que causan enfermedad.

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