53 research outputs found

    Observations on non-randomly distribution of spores of Henneguya spp. (Cnidaria, Myxosporea, Myxobolidae) within plasmodia

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    Species of the cnidarian genus Henneguya Thelohan, 1892 (Myxosporea: Myxobolidae) are histozoic parasites commonly found in freshwater and, more rarely, in marine fish. The development of these parasites in fish tissues includes the formation of plasmodia within which occurs the sporogony originating spores with two caudal processes, which are usually randomly distributed within the plasmodia. In this report the authors present some cases of non-random distribution of the spores of six species of Henneguya within their plasmodia. Two different patterns of non-random distribution were found based on a literature survey. These patterns and their origin are discussed. Apparently this non-random distribution of the spores is due to both internal and external factors.European Regional Development Fund (ERDF) through the COMPETE - Operational Competitiveness Programmenational funds through FCT - Foundation for Science and TechnologyCNPqGINOPUniv Porto, Fac Ciencias, Dept Biol, Rua Campo Alegre,Edificio FC4, P-4169007 Oporto, PortugalCIMAR, CIIMAR, Ctr Interdisciplinar Invest Marinha & Ambiental, Matosinhos, PortugalInst Super Engn Porto, Lab Engn Matemat LEMA, Oporto, Portugal|Univ Fed Sao Paulo, UNIFESP, Dept Ecol & Biol Evolut, Diadema, SP, BrazilUniv Estadual Campinas, Inst Biol, Dept Biol Anim, Campinas, SP, BrazilCtr Agr Res, Inst Vet Med Res, Budapest, HungaryHungarian Acad Sci MTA, Budapest, HungaryUniv Fed Sao Paulo, UNIFESP, Dept Ecol & Biol Evolut, Diadema, SP, BrazilEuropean Regional Development Fund (ERDF) through the COMPETE - Operational Competitiveness Programmenational funds through FCT - Foundation for Science and Technology: PEst-C/MAR/LA0015/2013CNPq: 305630/2013-0GINOP: 2.3.3-15-2016-00004Web of Scienc

    Infestación por larvas de Anisakis (Nematoda: Anisakidae) en el sable negro Aphanopus carbo (Osteichthyes: Trichiuridae) en aguas portuguesas

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    Aphanopus carbo, black scabbardfish, specimens from 3 Portuguese regions (the mainland, Madeira and the Azores) during four (mainland and Madeira) or two (Azores) seasons of the year were examined for the presence of Anisakis. All the fish examined (n=287) were infected with Anisakis L3 larvae (prevalence = 100%). Significant geographical differences in intensity were found: the Azores showed the lowest mean intensity value (53.7) and Madeira the highest one (253.9). The intensity of infection was positively correlated with the host length in specimens of Sesimbra and Madeira. Significant seasonal differences in intensity were found in the studied regions. The very high values in prevalence and intensity strongly suggest that the consumption of raw or undercooked black scabbard fish is a potential risk for human health.Se examinaron ejemplares de Aphanopus carbo de 3 regiones portuguesas (costa continental, Madeira y Azores) para determinar la presencia de Anisákidos durante cuatro (costa continental y Madeira) o dos (Azores) épocas del año. Todos los ejemplares examinados (n=287) estaban infectados por larvas L3 de Anisakis (prevalencia = 100%). Se encontraron diferencias geográficas significativas en la intensidad: Azores mostró el valor de intensidad media más bajo (53.7) y Madeira el más alto (253.9). La intensidad de infección mostró una correlación positiva con la talla del huésped en los casos de la costa continental y Madeira. Se encontraron diferencias estacionales significativas en la intensidad en las regiones estudiadas. Los altos valores encontrados en la prevalencia e intensidad sugieren que el consumo de sable negro crudo o medio crudo constituye un riesgo potencial para la salud humana

    Uso de parásitos como marcadores biológicos en la identificación de stocks de sable negro, Aphanopus carbo Lowe, 1839 (Osteichthyes: Trichiuridae) en aguas portuguesas

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    We studied the use of parasites as biological tags for discriminating fish stocks of Aphanopus carbo (Osteichthyes: Trichiuridae) from Portugal (Sesimbra on the mainland, Madeira and the Azores). Sixteen different metazoan parasites were found (14 from Madeira, 9 from Sesimbra and 7 from the Azores). Some parasites occurred only in fish from Madeira. The prevalence and mean intensity of the infection was recorded for each parasite and locality, and their values were statistically compared between the three sampling localities and related to host length classes. The differences between some of these parameters were statistically significant among the three localities or between two of them. It is suggested that 6 parasites (Tentacularia coryphaenae, Sphyriocephalus tergestinus, Campbelliella heteropoeciloacantha, Anisakis spp., Bolbosoma vasculosum and unidentified Acanthocephala larvae) can be used as biological tags to discriminate Portuguese stocks of Aphanopus carbo.Se estudió el uso de parásitos como marcadores biológicos para discriminar los stocks de Aphanopus carbo (Osteichthyes, Trichiuridae) de Portugal (Sesimbra en el continente, Madeira y Azores Islas). Dieciséis parásitos metazoarios fueron encontrados (14 en Madeira, 9 en Sesimbra y 7 en Azores). Algunos parásitos se presentaron sólo en Madeira. La prevalencia y la intensidad media de las infecciones fueron calculadas para cada parásito y cada región, y sus valores fueron comparados estadísticamente entre los tres lugares de muestreo, y relacionados con la talla del huésped. Se encontraron diferencias estadísticamente significativas entre algunos de estos parámetros de las tres regiones o entre dos de ellas. Se sugiere que 6 parásitos (Tentacularia coryphaenae, Sphyriocephalus tergestinus, Campbelliella heteropoeciloacantha, Anisakis spp., Bolbosoma vasculosum y larvas no identificadas de Acanthocephala) pueden ser usados como marcadores biológicos para discriminación de stocks de Aphanopus carbo de Portugal

    Phylogeny, ultrastructure, histopathology and prevalence of Myxobolus oliveirai sp. nov., a parasite of Brycon hilarii (Characidae) in the Pantanal wetland, Brazil

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    This paper presents the morphological, histological and ultrastructural characteristics of Myxobolus oliveirai sp. nov., a parasite of the gill filaments in Brycon hilarii from the Brazilian Pantanal. Out of 216 B. hilariispecimens examined (126 wild and 90 cultivated), 38.1% of wild specimens (n = 48) were infected. The parasites form elongated plasmodia primarily in the tip of gill filaments, reaching about 3 mm in length. A thorough comparison with all the Myxobolus species described from South American hosts, as well as nearly all the Myxobolus species described so far is provided. Partial sequencing of the 18S rDNA gene revealed a total of 1,527 bp. The Myxobolus species parasite of B. hilarii did not match any of the Myxozoa available in GenBank. In the phylogenetic analysis, M. oliveirai sp. nov. composed a monophyletic group with eight other species: five species of Myxobolus parasites of mugilid fishes, two parasites of pangasiid and one of centrarchid. Infection prevalence values of the parasite revealed no significant differences between wet and dry seasons or between males and females. The importance of the infection to the farming of the host species is emphasized.FAPESPCEPTA - ICMBioCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

    Phylogeny, ultrastructure, histopathology and prevalence of Myxobolus oliveirai sp. nov., a parasite of Brycon hilarii (Characidae) in the Pantanal wetland, Brazil

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    This paper presents the morphological, histological and ultrastructural characteristics of Myxobolus oliveirai sp. nov., a parasite of the gill filaments in Brycon hilarii from the Brazilian Pantanal. Out of 216 B. hilariispecimens examined (126 wild and 90 cultivated), 38.1% of wild specimens (n = 48) were infected. The parasites form elongated plasmodia primarily in the tip of gill filaments, reaching about 3 mm in length. A thorough comparison with all the Myxobolus species described from South American hosts, as well as nearly all the Myxobolus species described so far is provided. Partial sequencing of the 18S rDNA gene revealed a total of 1,527 bp. The Myxobolus species parasite of B. hilarii did not match any of the Myxozoa available in GenBank. In the phylogenetic analysis, M. oliveirai sp. nov. composed a monophyletic group with eight other species: five species of Myxobolus parasites of mugilid fishes, two parasites of pangasiid and one of centrarchid. Infection prevalence values of the parasite revealed no significant differences between wet and dry seasons or between males and females. The importance of the infection to the farming of the host species is emphasized1056762769sem informaçã

    Estructura de stock de sable negro (Aphanopus carbo Lowe, 1839) en el sur del Atlántico nordeste

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    Black scabbardfish stock structure is still unknown in European waters where, due to the scarcity of biological information, the ICES considers that there is a single stock unit. This study is the final outcome of a scientific project that applies a holistic approach to research on the population structure of the black scabbardfish and aims to define the most appropriate strategy for the conservation of this resource in southern NE Atlantic waters. The factors studied include life history parameters, otolith shape analysis, parasites, landings-and-effort data and contaminants. Sampling was conducted between 2005 and 2007 in three areas of the southern NE Atlantic: mainland Portugal, Madeira and the Azores. The mainland and the Azores have an established commercial fishery, whereas the Azores has only an exploratory fishery. The majority of results indicated the existence of different stocks of black scabbardfish in the study area. Of the 8 parameters, 6 were in agreement with separate stocks between the mainland and Madeira, 5 were in agreement with separate stocks between the mainland and the Azores, and 4 were in agreement with separate stocks between Madeira and the Azores.La estructura de la población de sable negro en las aguas europeas es todavía desconocida y, debido a la escasez de la información biológica disponible, ICES ha considerado una sola unidad de stock en la totalidad de dichas aguas. El proyecto que originó este estudio es un trabajo integrado para investigar la estructura poblacional de sable negro y pretende definir la estrategia más apropiada para la conservación de este recurso en aguas del sur del Atlántico nordeste. Para cumplir con el objetivo del proyecto se llevaron a cabo varios estudios: determinación de parámetros que definen el ciclo vital, análisis de forma del otolito, parásitos, datos de desembarques y esfuerzo pesquero, y contaminantes. El muestreo fue realizado entre 2005 y 2007 en tres áreas del sur del Atlántico nordeste: Portugal continental, aguas de Madeira y Azores. Las dos primeras áreas tienen una pesquería comercial establecida, mientras que en Azores existe una pesquería exploratoria. La mayoría de los resultados concluyeron la existencia de diferentes unidades poblacionales del sable negro en el área sur del Atlántico nordeste. Seis de los ocho parámetros confirman la separación entre los individuos del continente y Madeira, mientras que 5 parámetros corroboran la separación entre el continente y Azores. Solamente 4 técnicas corroboran la separación entre Madeira y Azores
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