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Sample records for lymnaea cubensis molusco

  1. Actividad molusquicida del Paraiso (Melia azedarach L. (Meliaceae sobre Lymnaea cubensis, molusco vector de Fasciolosis

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    Perez Marlene Piña

    1998-01-01

    Full Text Available INTRODUCCIÓN: La Fasciolosis constituye en diversas regiones una fuente importante de pérdidas económicas y cuando se descuidan las medidas de control de sus hospedadores (moluscos, junto a condiciones ecológicas favorables, pueden ocurrir casos aislados de Fasciolosis humana. Dentro de los métodos alternativos para su control está el uso de extractos vegetales y se pretendió evaluar el probable empleo del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. en el control de Lymnaea cubensis, principal vector de la Fasciolosis en Cuba. MATERIAL Y MÉTODO: Diferentes concentraciones del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. fueron testados para determinar las dosis letales media (DL50 y máxima (DL90 usando un programa computarizado Probit-Log. Siete series experimentales fueron probadas usando 72 moluscos en cada una. Para determinar la influencia sobre la frecuencia cardíaca fueron testados tres grupos de 10 moluscos, dos fueron tratados con las DL50=0,88627 y DL90=1,7641, respectivamente, mientras que el tercero fue considerado como testigo. RESULTADOS Y CONCLUSIONES: Se observó una marcada influencia de ambas dosis sobre la frecuencia cardíaca del molusco estudiado. Estos resultados son alentadores, pues demuestran el potencial empleo de esta planta en el control de moluscos indeseables.

  2. Actividad molusquicida del Paraiso (Melia azedarach L. (Meliaceae sobre Lymnaea cubensis, molusco vector de Fasciolosis

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    Marlene Piña Perez

    1998-06-01

    Full Text Available INTRODUCCIÓN: La Fasciolosis constituye en diversas regiones una fuente importante de pérdidas económicas y cuando se descuidan las medidas de control de sus hospedadores (moluscos, junto a condiciones ecológicas favorables, pueden ocurrir casos aislados de Fasciolosis humana. Dentro de los métodos alternativos para su control está el uso de extractos vegetales y se pretendió evaluar el probable empleo del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. en el control de Lymnaea cubensis, principal vector de la Fasciolosis en Cuba. MATERIAL Y MÉTODO: Diferentes concentraciones del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. fueron testados para determinar las dosis letales media (DL50 y máxima (DL90 usando un programa computarizado Probit-Log. Siete series experimentales fueron probadas usando 72 moluscos en cada una. Para determinar la influencia sobre la frecuencia cardíaca fueron testados tres grupos de 10 moluscos, dos fueron tratados con las DL50=0,88627 y DL90=1,7641, respectivamente, mientras que el tercero fue considerado como testigo. RESULTADOS Y CONCLUSIONES: Se observó una marcada influencia de ambas dosis sobre la frecuencia cardíaca del molusco estudiado. Estos resultados son alentadores, pues demuestran el potencial empleo de esta planta en el control de moluscos indeseables.

  3. Actividad molusquicida del Paraiso (Melia azedarach L. (Meliaceae sobre Lymnaea cubensis, molusco vector de Fasciolosis Molluscicidal activity of Paraiso (Melia azedarach L. (Meliaceae on Lymnaea cubensis, host snail of Fasciolosis

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    Marlene Piña Perez

    1998-06-01

    Full Text Available INTRODUCCIÓN: La Fasciolosis constituye en diversas regiones una fuente importante de pérdidas económicas y cuando se descuidan las medidas de control de sus hospedadores (moluscos, junto a condiciones ecológicas favorables, pueden ocurrir casos aislados de Fasciolosis humana. Dentro de los métodos alternativos para su control está el uso de extractos vegetales y se pretendió evaluar el probable empleo del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. en el control de Lymnaea cubensis, principal vector de la Fasciolosis en Cuba. MATERIAL Y MÉTODO: Diferentes concentraciones del jugo extraído del fruto y semillas del Paraiso (Melia azedarach L. fueron testados para determinar las dosis letales media (DL50 y máxima (DL90 usando un programa computarizado Probit-Log. Siete series experimentales fueron probadas usando 72 moluscos en cada una. Para determinar la influencia sobre la frecuencia cardíaca fueron testados tres grupos de 10 moluscos, dos fueron tratados con las DL50=0,88627 y DL90=1,7641, respectivamente, mientras que el tercero fue considerado como testigo. RESULTADOS Y CONCLUSIONES: Se observó una marcada influencia de ambas dosis sobre la frecuencia cardíaca del molusco estudiado. Estos resultados son alentadores, pues demuestran el potencial empleo de esta planta en el control de moluscos indeseables.INTRODUÇÃO: A Fasciolosis constitui em diversas regiões fonte importante de perdas econômicas, e quando não se adotam medidas de controle de seus hospedeiros (moluscos, junto a condições ecológicas favoráveis, pode ocorrer o aparecimento de casos isolados de Fasciolosis humana. Dentro dos métodos alternativos para o seu controle está o uso de extratos vegetais e se tem pretendido avaliar o provável emprego do suco extraído do fruto e sementes do Paraíso (Melia azedarach L., no controle de Lymnaea cubensis, principal vetor da Fasciolosis em Cuba. MATERIAL E MÉTODO: Diferentes concentra

  4. Infecção experimental de Physa cubensis Pfeiffer 1839 e Lymnaea columella com miracídios de Fasciola hepatica Linnaeus, 1758

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    Juliana SãoLuiz de Barros

    2002-01-01

    Full Text Available Foi realizada a infecção experimental de Physa cubensis Pfeiffer, 1839, com miracídios de Fasciola hepatica. Para tanto, cada um dos cem moluscos, selecionados para o experimento, foram infectados com três miracídeos. Alguns exemplares, escolhidos ao acaso, foram mantidos até o 60º dia para observação da emergência de formas larvais. Os moluscos restantes foram fixados após 0,5; 1; 2; 3; 4; 5; 24; 48; 72; 96; 120 e 144 horas de infecção, utilizando Raillet & Henry. O trabalho foi realizado de forma comparativa com Lymnaea columella. Os resultados demonstraram o desenvolvimento das formas larvais do trematódeo em L. columella e a presença de esporocistos em vários estágios de degeneração na região cefalopodal e na região do manto nos primeiros dias de infecção em P. cubensis.

  5. Moluscos

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    Grande, Cristina; Zardoya, Rafael

    2014-01-01

    El éxito evolutivo de los moluscos queda patente en la gran cantidad de especies vivas existentes (son el segundo filo de metazoos más diverso), así como en su abundancia y en su capacidad de colonizar casi cualquier hábitat. Los moluscos representan una parte importantísima de la biomasa marina, pero también se han adaptado de manera exitosa al medio terrestre y al dulceacuícola. Se caracterizan por la presencia de 1) rádula, un órgano especializado para la alimentación; 2) manto, u...

  6. Characterisation of Lymnaea cubensis, L. viatrix and L. neotropica n. sp., the main vectors of Fasciola hepatica in Latin America, by analysis of their ribosomal and mitochondrial DNA.

    Science.gov (United States)

    Bargues, M D; Artigas, P; Mera Y Sierra, R L; Pointier, J P; Mas-Coma, S

    2007-10-01

    Although, in the endemic areas throughout the world, human fascioliasis presents varying patterns in its epidemiology, the species of lymnaeid snail that act as intermediate hosts and vectors are always crucial in the transmission of the causative parasites. Species in the Galba/Fossaria group of snails, such as Lymnaea cubensis, L. viatrix var. A ventricosa, L. viatrix var. B elongata and Galba truncatula, appear to be frequently involved in the transmission of Fasciola hepatica in Central and South America, although specific classification within this morphologically and anatomically confusing group is often very difficult. To explore the potential use of molecular analyses in the identification of vector snails, regions of the ribosomal DNA - the small subunit (18S) gene and internal transcribed spacers (ITS-2 and ITS-1) - and of the mitochondrial DNA - the cytochrome c oxidase subunit I (COI) - of wild-caught lymnaeid snails of L. cubensis, L. viatrix var. A ventricosa, L. viatrix var. B elongata and G. truncatula have been sequenced. The samples of the Latin American species included specimens from the respective type localities. The genetic distances observed and the results of phylogenetic analyses demonstrate that two different species exist within L. viatrix. Lymnaea neotropica n. sp. (=L. viatrix var. B elongata) is here proposed for specimens from Lima, Peru, and is differentiated from L. viatrix (=L. viatrix var. A ventricosa), L. cubensis and G. truncatula. The data collected on the 18S ribosomal-RNA gene indicate that the snails investigated may cover more than one supraspecific taxon. The ITS-2, ITS-1 and COI nucleotide sequences are clearly useful markers for the differentiation of these morpho-anatomically similar lymnaeid species. The numerous microsatellite repeats found within ITS-2 are potential tools for differentiation at population level.

  7. Пути проникновения мирацидиев Fasciola hepatica (Linnaeus,1758) в гепатопанкреас Lymnaea truncatula Muller, 1774 и Lymnaea cubensis Pfeiffer, 1839 и возникающие патологии

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    Соколина Ф.; Игнатьев Г.; Villasenor O.C.; Sanchez-Vega J.T.

    2010-01-01

    The investigation the mollusk tissue of Lymnaea truncatula Muller, 1774 and Lymnaea cubensis Pfeiffer, 1839 during the infection of miracidia Fasciola hepatica (Linnaeus, 1758) showed the dissolution of the intercellular substance, deformation the cells of the mollusk connective tissue, demolish of epithelium and liver tissue.

  8. Squalus cubensis Reproduction Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Reproductive data from Squalus cubensis (Cuban dogfish) were opportunistically collected from 2005-2012. Data include those necessary to examine reproductive cycle,...

  9. Lymnaea columella in northern Brazil

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    W. Lobato Paraense

    1983-12-01

    Full Text Available The occurrence of a mollusc of the family Lymnaeidae is recorded for the first time in Brazil north of parallel 15ºS, as a result of the finding of Lymnaea columella in Manus and Benjamin Constant, state of Amazonas. A description is given of its shell, renal organ, genital system and radula, pointing to the morphological characteristics of diagnostic value to separate it from two other species previously studied by the author, Lymnaea viatrix and L. rupestris, which also occur in Brazil.Pela primeira vez é verificada a ocorrência de um molusco da família Lymnaeidae ao norte do paralelo 15ºS no Brasil, como resultado do encontro da lYmnaea columella em Manus e Benjamin Constant, Estado do Amazonas. É apresentada uma descrição da concha, do órgão renal, do sistema genital e da rádula, sendo indicados os caracteres morfológicos que permitem distinguir a Lymnaea columella de outras espécies que também ocorrem no Brasil, previamente estudadas pelo autor, L. viatrix e L. rupestris.

  10. Molusco contagioso em tatuagem

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    Molina, Luciana [UNESP; Romiti, Ricardo

    2011-01-01

    Molusco contagioso é uma dermatovirose causada por poxvírus e caracterizada por erupção benigna e autolimitada de uma ou múltiplas pápulas esféricas e brilhantes. A transmissão habitualmente ocorre por contato direto com indivíduos infectados. Relata-se caso de doente masculino, 22 anos, com história de surgimento de numerosas pápulas umbilicadas localizadas estritamente sobre a região de uma tatuagem. Exame histopatológico de uma das pápulas confirmou a hipótese clínica de molusco contagioso...

  11. Lymnaea columella: two new Brazilian localities in the states of Amazonas and Bahia

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    W. Lobato Paraense

    1986-03-01

    Full Text Available The occurrence of Lymnaea columella is recorded in Tefé, Amazonas state, where it was found together with Drepanotrema anatinum, Physa marmorata and pomacea sp. L. columella was also collected in Salvador, Bahia state, at the dique do Tororó, an urban lake formely mentioned (as "lac Baril" by Moricand (1853 as a breeding-place of Biomphalaria glabrata, Drepanotrema cimex, D. depressissimum, Pomacea lineata, P. decussata and Ancylus moricandi. The four first-mentioned species, as well as physa cubensis and Hemisinus brasiliensis, were also collected now. This is the first record of a lymnaeid in the Northeastern region of Brazil.É registrada a ocorrência de Lymnaea columella em Tefé, Estado do Amazonas, onde foi encontrada juntamente com Physa marmorata e Pomacea sp. L. columella foi também coletada em Salvador, Estado da Bahia, no Dique do Tororó, lago urbano antes mencionado por Moricand (1853 como criadouro de Biomphalaria glabrata, Drepanotrema cimex, D. depressissimum, Pomacea lineata, P. decussata e Ancylus moricandi. As quatro primeiras espécies mencionadas, assim como Physa cubensis e Hemisinus brasiliensis, também foram agora coletadas. Este é o primeiro registro de um limneídeo na região Nordeste do Brasil

  12. Moluscos límnicos de uma área do Alto Araguaia (Brasil Limnic molluscs from Alto Araguaia area (Brazil

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    Horácio Manuel Santana Teles

    1991-06-01

    Full Text Available São mostrados os resultados do levantamento dos moluscos de água doce de 5 municípios da área de influência de uma usina hidrelétrica em estudo, formada pelas redondezas da Cachoeira Couto Magalhães no Rio Araguaia. Foram examinados 624 moluscos procedentes de amostras coletadas em 20 coleções hídricas. O exame revelou a ocorrência de 8 gastrópodos pulmonados e um prosobrânquio, além de um bivalvo esferídeo. Devido ao envolvimento com a saúde pública, merece destaque o encontro de Biomphalaria straminea e Lymnaea columella, respectivamente hospedeiros intermediários de Schistosoma mansoni e Fasciola hepatica.An analysis was carried out to determine the natural population of freshwater molluscs from 5 municipalities within the area of influence of the Couto Magalhães hidroeletric project. These municipalities cover a large area of the State of Goiás and Mato Grosso do Sul (Brazil. In this study 624 molluscs of the following species were examined: Drepanotrema anatinum, D. lucidum, D. depressissimum, Biomphalaria straminea, D. schrammi, Physa marmorata, Lymnaea columella, Pomacea and Eupera. One to their importance in public health, the discovery of Biomphalaria straminea and Lymnaea columella, intermediate hosts, respectively, of Shistosoma mansoni and Fasciola hepatica, deserves special mention.

  13. Physa cubensis Pfeiffer, 1839 (Pulmonata: Physidae

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    W. Lobato Paraense

    1987-03-01

    Full Text Available A description of Physa cubensis Pfeiffer, 1839, based on 15 speciments collected in Havana, Cuba, is presented. The shell, measuring 9.0 x 4,8mm to 12.3 x 6.4mm, is ovate-oblong, thin, diaphanous, horncolored, shining. Spire elevated, broadly conical; protoconch distinct, roundish, reddish-brown. About five moderately shouldered, roundly convex whorls, penultimate whorl expanded; spiral striation subobsolete; growth line faint on the intermediate whorls, clearly visible on the body whorl, crowded here and there. Suture well impressed. Aperture elongated 2.05 - 2.67 (mean 2.27 times as long as the remaining length of the shell, narrow obovulate-lunate; upper half acute-angled, lower half oval, narrowly rounded at the base; outer lip sharp, inner lip completely closing the umbilical region; a thick callus on the parietal wall; columellar plait well marked. Ratios: shell width/shell length - 0.52-0.61 (mean 0.55; spire length/shell length = 0.27 - 0.33 (mean 0.31; aperture length/shell length = 0.67 - 0.73 (mean 0.69. Oral lappets laterally mucronate; foot spatulate with acuminate tail. Mantle relection with 6 - 8 short triangular dentations in the right lobe (columellar side and 4 - 6 in the left lobe (near the pneumostome. Renal tube tightly folded into a zigzag course. Ovotestis, ovispermiduct, seminal vesicle, oviduct, nidamental gland, uterus and vagina as in Physa marmorata (see Paraense, 1986, Mem. Inst. Oswaldo Cruz, 81: 459-469. Spermathecal body egg-shaped or pear-shaped; spermathecal ducta uniformly narrow with expanded base, a little longer than the body. Spermiduct, prostate and vas deferens as in P. marmorata (Paraense, loc. cit.. Penis wide proximally, narrowing gradually apicad; penial canal with subterminal outlet. Penial sheath following the width of the penis and ending up by a bulbous expansion somewhat narrower than the proximal portion. Penaial sheath/prepuce ration = 1,25 - 1,83 (mean 1.49. Prepuce much wider than the bulb of

  14. Atração miraxonal exercida por Biomphalaria straminea, Lymnaea columella e Physa sp, sobre miracídios de Schistosoma mansoni da linhagem BH The miraxonal attraction exercised by Biomphalaria straminea, Lymnaea columella and Physa sp over miracidia of Schistosoma mansoni

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    Luiz A. Magalhães

    1991-02-01

    Full Text Available Utilizando-se um artefato de vidro composto de duas câmaras unidas por um canal, testamos a atração miraxonal exercida por Biomphalaria straminea, Lymnaea columella e Physa sp, sobre larvas de Schistosoma mansoni da linhagem BH. Os moluscos, ou suas águas de condicionamento (SCW, foram colocados aleatoriamente em uma das câmaras, contendo o restante do artefato somente água declorada. Dez miracídios foram depositados no centro do canal. O comportamento dos miracídios foi observado por 15 min. Foram feitas dez replicações de cada experimento, utilizando-se espécimens de moluscos e miracídios diferentes. Verificou-se que todos os moluscos e suas SCW exerceram atração miraxonal, sendo que Physa sp atraiu mais que Lymnaea columella. Foi isolado um único exemplar de B. straminea que exerceu efeito repulsivo sobre os miracídios de S. mansoni.The attraction exercised over Schistosoma mansoni miracidia by Biomphalaria straminea, Lymnaea columella and Physa sp using a specially designed apparatus consisting of two circular glass chambers joined by an open channel were studied. The molluscs or their snail-conditioned water (SCW was placed in one of the chambers (randomly chosen. In the channel ten miracidia was deposited and the count of miracidia in each of the three compartments (the two chambers and the channel was recorded during fifteen minutes. Ten replications of each experiment with different specimens of molluscs and miracidia were made. Statistical and ad-hoc exploratory data analysis showed that: a the three species of molluscs and their SCW attract the miracidia; b Physa sp attract more miracidia then L. columella. There was an isolated single B. straminea specimen that had a repulsive effect to the miracidia.

  15. mRNA-Seq analysis of the Pseudoperonospora cubensis transcriptome during cucumber (Cucumis sativus L. infection.

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    Elizabeth A Savory

    Full Text Available Pseudoperonospora cubensis, an oomycete, is the causal agent of cucurbit downy mildew, and is responsible for significant losses on cucurbit crops worldwide. While other oomycete plant pathogens have been extensively studied at the molecular level, Ps. cubensis and the molecular basis of its interaction with cucurbit hosts has not been well examined. Here, we present the first large-scale global gene expression analysis of Ps. cubensis infection of a susceptible Cucumis sativus cultivar, 'Vlaspik', and identification of genes with putative roles in infection, growth, and pathogenicity. Using high throughput whole transcriptome sequencing, we captured differential expression of 2383 Ps. cubensis genes in sporangia and at 1, 2, 3, 4, 6, and 8 days post-inoculation (dpi. Additionally, comparison of Ps. cubensis expression profiles with expression profiles from an infection time course of the oomycete pathogen Phytophthora infestans on Solanum tuberosum revealed similarities in expression patterns of 1,576-6,806 orthologous genes suggesting a substantial degree of overlap in molecular events in virulence between the biotrophic Ps. cubensis and the hemi-biotrophic P. infestans. Co-expression analyses identified distinct modules of Ps. cubensis genes that were representative of early, intermediate, and late infection stages. Collectively, these expression data have advanced our understanding of key molecular and genetic events in the virulence of Ps. cubensis and thus, provides a foundation for identifying mechanism(s by which to engineer or effect resistance in the host.

  16. Aislamiento de enterobacterias en algunos moluscos del mar peruano

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    Dora A. Taboada P.

    2014-06-01

    Full Text Available En este trabajo se da a conocer el resultado de un estudio bacteriológico en 5 especies de moluscos que se utilizan en la alimentación humana, ellos fueron: Aulacomya ater, Gari sp., Mesodesma donacium, Aequipecten purpuratus y Thais chocolata, obtenidos de diversos centros de expendio del Callao y Lima. Se aisló Salmonella enteritidis serotipo Derby y Edwardsiella de Gari sp. Otras bacterias como Proteus, Citrobacter, Enterobacter y Serratia estuvieron presentes en los diversos moluscos. El 100% de ellos presentó contaminación por E. coli.

  17. Moluscos continentales de México: Dulceacuícolas

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    Edna Naranjo García

    2003-01-01

    Se han registrado 16 familias de moluscos dulceacuícolas en México, de ellos los estudios que se han realizado abarcan aspectos como el tipo de hábitat y la distribución de algunas especies. Las investigaciones sobre comportamiento así como de la biología de la especie Pomacea flagellata son las mas amplias con respecto a las otras especies de moluscos dulceacuícolas. En cuanto a estudios sobre la reproducción, estos se han realizado en Pomacea patula catemacensis. Mientras que solamente se e...

  18. Speed of back-swimming of Lymnaea.

    Science.gov (United States)

    Aono, Kanako; Fusada, A; Fusada, Y; Ishii, W; Kanaya, Y; Komuro, Mami; Matsui, Kanae; Meguro, S; Miyamae, Ayumi; Miyamae, Yurie; Murata, Aya; Narita, Shizuka; Nozaka, Hiroe; Saito, Wakana; Watanabe, Ayumi; Nishikata, Kaori; Kanazawa, A; Fujito, Y; Okada, R; Lukowiak, K; Ito, E

    2008-01-01

    The pond snail, Lymnaea stagnalis, can locomote on its back utilizing the surface tension of the water. We have called this form of movement 'back-swimming'. In order to perform this behavior, the snail must flip itself over on its back so that its foot is visible from above. Little is known about the mechanism of this back-swimming. As a first step for the elucidation of this mechanism, we measured the speed of back-swimming of Lymnaea at the different times of the day. They back-swam significantly faster in the morning than just before dark. These data are consistent with our earlier findings on circadian-timed activity pattern in Lymnaea. Lymnaea appear to secrete a thin membrane-like substance from their foot that may allow them to back-swim. To confirm the existence of this substance and to examine whether this substance is hydrophobic or hydrophilic, we applied a detergent onto the foot during back-swimming. A single drop of 1% Tween 20 drifted Lymnaea away that were still kept at the water surface. These results suggest that Lymnaea secrete a hydrophobic substance from their foot that floats to the water surface allowing Lymnaea to back-swim.

  19. Estado actual del cultivo de moluscos en México

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    Carlos Cáceres Martínez

    1999-01-01

    Full Text Available Se analizan los resultados de la producción nacional de acuacultura para 1997 en función de su origen y destino. Se discute la importancia relativa del cultivo de moluscos y se emiten recomendaciones para organizar el esfuerzo de los productores y académicos para impulsar su desarrollo.

  20. Susceptibility level of cucumber downy mildew (Pseudoperonospora cubensis to metalaxyl

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    Bagi Ferenc F.

    2009-01-01

    Full Text Available Level of susceptibility of Pseudoperonospora cubensis isolate from Ratkovo to metalaxyl in concentrations 50, 100, 200, 400 and 800 μg/ml was investigated. The trials were conducted on cotyledon and fully developed young leaves using cucumber cultivar Haroš. Reduced level of susceptibility was detected in metalaxyl concentrations of 50, 100 and 200 μg/ml because the intensity of sporulation in these treatments was on the same level as in control. Sporulation was also observed on developed leaves treated with metalaxyl in concentrations of 400 and 800 μg/ml.

  1. Potencial agroecológico de Ateleia cubensis (DC Dietr. var. cubensis (Griseb. Mohlenber en condiciones naturales del núcleo ultramáfico de Camagüey/Agroecological potential of Ateleia cubensis (DC Dietr. var. cubensis (Griseb. Mohlenber in natural conditions of Camagüey ultramafic core

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    Delmy Triana González

    2014-09-01

    Full Text Available RESUMEN Con el objetivo de evaluar el potencial agroecológico de Ateleia cubensis (DC Dietr. var. cubensis (Griseb. Mohlenber en condiciones naturales del núcleo ultramáfico de Camagüey, se desarrolló un estudio en el municipio Minas, durante los meses comprendidos entre enero del 2014 y enero del año 2015, sobre un suelo Fersialítico rojo pardusco ferromagnesial (Inceptisol - Cambisol. Se estimó la densidad natural de la especie en el área a través de 20 parcelas de muestreo permanentes (36 m2 distribuidas aleatoriamente, se determinó la densidad de la madera para ser utilizada en el cálculo del carbono retenido, el volumen de madera, raíces, follaje y hojarasca. Los resultados muestran una densidad de 8 055 plantas /ha de A. cubensis con beneficios desde el punto de vista agroecológico reconocido por las bondades que ofrece al ecosistema. ABSTRACT Agroecological potential of Ateleia cubensis (DC Dietr. var. cubensis (Griseb. Mohlenber in natural conditions of Camagüey ultramafic core In order to evaluate the agroecological potential of o Ateleia cubensis (DC Dietr. var. cubensis (Griseb. Mohlenber in natural conditions of Camagüey ultramafic core, a study was conducted in the municipality Minas, during the months between January 2014 and January 2015, on a brownish red soil Fersialitic ferromagnesian (Inceptisol - Cambisol. The natural density of the species in the area through 20 permanent sample plots (36 m2 randomly distributed, estimated density of the wood to be used in the calculation of carbon retained, the volume of wood, roots, foliage was determined and stubble. The results show a density of 8 055 plants / ha of A. cubensis with benefits from the agroecological point of view recognized the advantages offered to ecosystem.

  2. Germinación in vitro de Pinus cubensis Griseb

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    Raima Cantillo Ardebol

    2006-01-01

    Full Text Available Se hace alusión a la micropropagación de Pinus cubensis, Griseb, como aspecto que satisface la demanda de semillas para la reforestación en áreas de Pinares de Mayarí, hábitat de esta endémica región, amenazada por minería y explotación maderera. Se utilizaron semillas, determinando el mejor método de desinfección, evaluando su germinación en medio con diferentes composiciones de reguladores del crecimiento, y la influencia de la presencia o ausencia de la cubierta seminal. El mejor resultado se obtuvo con Cloralex al 20% durante 15 minutos e implantando semillas sin testa en medio MS libre de reguladores del crecimiento.

  3. Biology and behavior of the seed borer wasp Bephratelloides cubensis Ashmead (Hymenoptera: Eurytomidae); Biologia y habitos del barrenador de la semilla Bephratelloides cubensis Ashmead (Hymenoptera: Eurytomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Fuentes, Luis M.; Urias-Lopez, Mario A., E-mail: hernandez.luismartin@inifap.gob.m, E-mail: urias.marioalfonso@inifap.gob.m [Instituto Nacional de Investigaciones Forestal000, Agricolas y Pecuarias, Santiago, Nayarit (Mexico). Campo Experimental Santiago Ixcuintla; Bautista-Martinez, Nestor, E-mail: nestor@colpos.m [Instituto de Fitosanidad, Montecillo, Texcoco (Mexico). Colegio de Postgraduados

    2010-07-15

    The sour sop Annona muricata is an important fruit for national market, and for exportation, but the crop is affected by pests and diseases. The seed borer wasp Bephratelloides cubensis Ashmead is the pest that produces the highest damage to the crop in Mexico. Sixty percent of damaged fruits and 5-50 seeds per fruit have been registered, with 25% reduction in yield. In Nayarit, Mexico, 100% of damaged fruits were recorded. In this State, an experiment with sour sop was conducted to study the life cycle under fi eld conditions and to determine diurnal behavior of the female of B. cubensis. The highest activity of the wasp was observed between 12:00 h and 13:00 h (35 degree C, 54% RH and 409.34 luxes). Females oviposited in fruits with a diameter of 3.1-7.6 cm. Larvae of B. cubensis developed five instars, adults survived no longer than 22 days, and female survived longer than males; they lived 22 and 15 days, respectively. Life cycle of B. cubensis varied from 69 to 122 days. (author)

  4. Dinâmica de Lymnaea columella (Say, 1817, hospedeiro intermediário de Fasciola hepatica (Linnaeus, 1758 em municípios do Estado de São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Edwin Alberto Pile Maure

    1998-01-01

    Full Text Available A dinâmica populacional de Lymnaea columella na pastagem foi estudada por um período de seis anos em fazendas de exploração leiteira positivas para Fasciola hepatica. A pesquisa foi desenvolvida nos municípios de Piquete e Redenção da Serra, Estado de São Paulo. Os resultados obtidos foram diferentes em cada fazenda, revelando que a dinâmica da população de moluscos está estreitamente relacionada a fatores ecológicos e climáticos. No município de Piquete, o aumento da variação da densidade populacional flutua em relação inversa à temperatura e à pluviosidade, encontrando maior número de moluscos no período seco do ano (maio-outubro. No município de Redenção da Serra, a grande quantidade de matéria orgânica observada no biótopo foi responsável pela captura do maior número de moluscos no período de altas temperaturas e chuvas (janeiro-março.

  5. Molusco contagioso em tatuagem Molluscum contagiosum on tattoo

    Directory of Open Access Journals (Sweden)

    Luciana Molina

    2011-04-01

    Full Text Available Molusco contagioso é uma dermatovirose causada por poxvírus e caracterizada por erupção benigna e autolimitada de uma ou múltiplas pápulas esféricas e brilhantes. A transmissão habitualmente ocorre por contato direto com indivíduos infectados. Relata-se caso de doente masculino, 22 anos, com história de surgimento de numerosas pápulas umbilicadas localizadas estritamente sobre a região de uma tatuagem. Exame histopatológico de uma das pápulas confirmou a hipótese clínica de molusco contagioso. Os autores descrevem uma manifestação pouco frequente da disseminação desse vírus em tatuagens e apresentam uma revisão da literatura, enfatizando as vias de transmissão e a terapêutica do molusco contagioso.Molluscum contagiosum is a disease caused by a poxvirus characterized by benign self-limited eruption of single or multiple cutaneous spherical and pearly papules. Transmission usually occurs by direct contact with infected hosts. It is reported the case of a 22-year-old Caucasian male who presented characteristic pearly and umbilicated papules strictly located on the region of a tattoo. Histopathologic exam confirmed the diagnosis of molluscum contagiosum. The authors describe an uncommomn manifestation of dissemination of this virus in tattoos and also present a literature review emphasizing the transmission pathways and treatment of Molluscum contagiosum.

  6. Moluscos continentales de México: Dulceacuícolas

    OpenAIRE

    2016-01-01

    There are 16 freshwater mollusc families reported from Mexico, but besides a few studies of habitat and distribution, only Pomacea flagellata, Pomacea patula catemacensis and Helisoma trivolvis has been studied in some detail, mainly regarding reproduction. In Mexico, the parasite Fasciola hepatica is transmitted by Lymnaea obrussa, L. humilis and L. cubense). Larval trematodes have been found in Planorbidae, Physidae, Lymnaeidae, Ancylidae and Pisidiidae. Diet and growth have been studied fo...

  7. Resposta tissular em infecções por Fasciola hepatica em Lymnaea viatrix. Epidemiologia da fasciolose no gado bovino da provincia de valdivia, Chile

    OpenAIRE

    Jorge Blas Ladislao Franjola Tepper

    2000-01-01

    Resumo: Fasciola hepatica é um parasito que tem como habitat os duetos biliares de animais herbívoros e onívoros e apresenta um ciclo biológico indireto, tendo como hospedeiro intermediário um molusco pulmonado, cuja espécie, no Chile, é Lymnaea viatrix. Na presente investigação estudou-se a resposta tissular de L. viatrix frente à infecção por Fasciola hepatica. Nesta investigação foram realizadas observações histológicas nas primeiras 72 horas após a infecção. A reação tissular iniciou-se à...

  8. Susceptibilidade de Lymnaea (pseudosuccinea columella (Say, 1817 exposta à infecção por miracídios de Fasciola hepatica (Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Alfredo Raimundo Corrêa Dacal

    1988-10-01

    Full Text Available Com o objetivo de estudar a susceptibilidade de Lymnaea (pseudosuccinea columella de Minas Gerais, Estado onde ainda não se registraram casos autóctones de fasciolose hepática, foram utilizadas as amostras MG 1, MG 2, MG 3 e MG 4, provenientes de diferentes regiões deste Estado, para estudo comparativo com as amostras RJ e RGS procedentes dos Estados do Rio de Janeiro e Rio Grande do Sul, áreas de focos de fasciolose. A amostra de Fasciola hepatica utilizada era procedente de ovinos abatidos no município de Camapuã, no Rio Grande do Sul, e foi mantida em coelhos. Os moluscos foram infectados com 6, 8 e 10 miracídos por molusco, sendo estudadas as incidências de infecção e de mortalidade. Nas condições que se realizou o trabalho diante dos resultados obtidos, foram tiradas as seguintes conclusões: 1. A mortalidade dos caramujos parece não estar diretamente relacionada com a percentagem de infecção; 2. As amostras de Lymnaea (pseudosuccinea columella de Minas Gerais, do Rio de Janeiro e do Rio Grande do Sul mostraram-se identicamente susceptíveis à infecção por Fasciola hepatica; 3. A população humana e os rebanhos bovino, ovino e suíno de Minas Gerais, particularmente aqueles do Vale do Rio Paraíba, podem ser considerados sujeitos à infecção por Fasciola hepatica.

  9. Malacología Latinoamericana: Moluscos de agua dulce de Argentina

    Directory of Open Access Journals (Sweden)

    Alejandra Rumi

    2008-03-01

    Full Text Available Se presenta un estado de situación y una lista actualizada y comentada sobre las especies de moluscos de agua dulce de la República Argentina. Se aborda en Gastropoda y Bivalvia la distribución a nivel de familias; las entidades endémicas, exóticas, invasoras y de importancia sanitaria. Los moluscos relacionados a la cuenca del Plata presentan la mayor riqueza específica. Base de datos: 4 500 registros relevados de las tres colecciones más importantes de la Argentina: MLP, MACN y FML. Además, se incluye información de recolecciones actuales y localidades citadas por otros autores. Hasta el presente han sido descritas 166 especies. De ellas 101 pertenecen a 10 familias de Gastropoda y 65 a 7 de Bivalvia. Las familias que presentan mayor riqueza específica son Lithoglyphidae (22 y Sphaeriidae (25, respectivamente. Sphaeriidae, Cochliopidae, Chilinidae y Lymnaeidae se distribuyen prácticamente en todo el país. Erodonidae y Solecurtidae se registran en ambientes mixohalinos de la provincia de Buenos Aires. Thiaridae y Glacidorbiidae presentan una distribución muy restringida. Especies endémicas de la Argentina: Gastropoda: Ampullariidae (1, Cochliopidae (10, Lithoglyphidae (11, Thiariidae (3, Chilinidae (11, Lymnaeidae (2 y Physidae (2?; Bivalvia: Hyriidae (1?; Etheriidae (1? y Sphaeriidae (10. Especies de interés sanitario: propagadoras de: Esquistosomiasis, Biomphalaria peregrina, B. straminea y B. tenagophila (Planorbidae; Fasciolasis, Lymnaea viatrix y L. columnella (Lymnaeidae; y dermatitis esquistosómicas, Chilina gibbosa y C. fluminea (Chilinidae. Especies de origen asiático: Corbicula fluminea (Corbiculidae y Limnoperna fortunei (Mytilidae. Es prioritaria la formación de áreas protegidas para la conservación de especies endémicas, especialmente de la Mesopotamia Argentina.Latin American Malacology. Freshwater Mollusks from Argentina. A report and an updated list with comments on the species of freshwater molluscs of

  10. Effects of Tarantula cubensis D6 on aflatoxin-induced injury in biochemical parameters in rats.

    Science.gov (United States)

    Karabacak, Mürsel; Eraslan, Gökhan; Kanbur, Murat; Sarıca, Zeynep Soyer

    2015-07-01

    Aflatoxins are toxic fungal metabolites that have adverse effects on humans and animals. Tarantula cubensis D6 is used as a homeopathic medicine for different purposes. The present study investigates the effects of Tarantula cubensis D6 on the oxidant-antioxidant balance and some biochemical parameters against exposure to aflatoxin. Thirty-two Sprague-Dawley female rats were used and evenly divided into four groups. Group 1 served as control. Groups 2, 3, and 4 received 200 μl/kg.bw/day Tarantula cubensis D6 (applied subcutaneously), 400 μg/kg.bw/day total aflatoxin (approximately 80% AF B1, 10% AF B2, 6 %AF G1, and 4% AF G2), and 200 μl/kg.bw/day Tarantula cubensis D6 plus 400 μg/kg.bw/day total aflatoxin, respectively, for 28 days. At the end of 28 days, blood samples and some organs (liver, kidney, brain, and spleen) were taken from all the animals. Oxidative stress markers (MDA, SOD, CAT, GSH-Px) and some biochemical parameters (glucose, triglyceride, cholesterol, BUN, creatinine, AST, ALT and ALP, total protein, albumin) were evaluated in blood samples and tissues. Aflatoxin caused negative changes in all oxidative stress parameters and some biochemical parameters (glucose, triglyceride, cholesterol, creatinine, AST, ALT, ALP, total protein, albumin). Administration of Tarantula cubensis D6 partly alleviated aflatoxin-induced negative changes. Our results indicated that Tarantula cubensis D6 partially neutralized the deleterious effects of aflatoxin. Copyright © 2015 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  11. Alterações histológicas em Lymnaea columella provocadas pelo látex de Euphorbia splendens var. hislopii

    Directory of Open Access Journals (Sweden)

    Samanta Moura de Araújo

    2002-01-01

    Full Text Available Observações histológicas em moluscos da espécie Lymnaea columella foram realizadas para determinar a existência ou não de alterações provocadas pelo uso do látex de Euphorbia splendens var. hislopii. O experimento foi realizado de acordo com os métodos padronizados pela OMS. Cinqüenta exemplares de L. columella, com comprimento de concha de 6±1mm, foram submetidos a 200ml das soluções nas concentrações de 0,47µl/L; 0,76µl/L; 0,94µl/L e 1,51µl/L, durante 24 horas. Após o evento experimental, os moluscos foram colocados em solução de Raillet & Henry, para sacrifício e fixação. Os resultados demonstraram lesões caracterizadas por degeneração, necrose e acúmulo de líquido na glândula digestiva e no rim, em exemplares submetidos a concentrações a partir de 0,47 mil/L.

  12. [Biology and behavior of the seed borer wasp Bephratelloides cubensis ashmead (Hymenoptera: Eurytomidae)].

    Science.gov (United States)

    Hernández-Fuentes, Luis M; Urias-López, Mario A; Bautista-Martínez, Nestor

    2010-01-01

    The soursop Annona muricata is an important fruit for national market, and for exportation, but the crop is affected by pests and diseases. The seed borer wasp Bephratelloides cubensis Ashmead is the pest that produces the highest damage to the crop in Mexico. Sixty percent of damaged fruits and 5-50 seeds per fruit have been registered, with 25% reduction in yield. In Nayarit, Mexico, 100% of damaged fruits were recorded. In this State, an experiment with soursop was conducted to study the life cycle under field conditions and to determine diurnal behavior of the female of B. cubensis. The highest activity of the wasp was observed between 12:00h and 13:00h (35ºC, 54% RH and 409.34 luxes). Females oviposited in fruits with a diameter of 3.1-7.6 cm. Larvae of B. cubensis developed five instars, adults survived no longer than 22 days, and female survived longer than males; they lived 22 and 15 days, respectively. Life cycle of B. cubensis varied from 69 to 122 days.

  13. Acute toxicity of Psilocybe cubensis (Ear. Sing., Strophariaceae, aqueous extract in mice Toxicidade aguda do extrato aquoso de Psilocybe cubensis em camundongos

    Directory of Open Access Journals (Sweden)

    Thiago Berti Kirsten

    2010-07-01

    Full Text Available Psilocybe cubensis (Ear. Sing., Strophariaceae, is a hallucinogen mushroom that has been used since the old times by humans, causing several psychotic effects. P. cubensis contains two tryptamine derivates: psilocybin and psilocin, agonists of the 5-HT2 receptor (serotonin. The main objective of this study was to investigate the acute toxicity effects of P. cubensis aqueous extract (PCAE administration in mice. Male and female adult Swiss mice received PCAE 0.1 mL/10 g i.p., and were observed individually, directly in a glass box and in an open-field. In relation to the data of the control group, PCAE-treated animals presented: an increased gnawing, appearance of wet-dog shakes and a decreased locomotion and rearing frequencies after 29-38 min. Also a clear gender difference was detected, being female mice more sensible to the PCAE than males. It was suggested that PCAE administration produced specific effects on mice behaviors, characteristic of drugs which interfere on central serotonergic and dopaminergic systems. Finally, the observational methods here employed were efficient to evaluate the toxic effects of the extract.O Psilocybe cubensis (Ear. Sing., Strophariaceae, é um cogumelo alucinógeno usado pelos humanos desde a antiguidade, causando diversos efeitos psicóticos. Ele contém dois derivados triptamínicos: psilocibina e psilocina, agonistas do receptor 5-HT2 (serotonina. O objetivo deste trabalho foi investigar os efeitos da administração do extrato aquoso do P. cubensis (EAPC na toxicidade aguda de camundongos. Camundongos Swiss adultos machos e fêmeas receberam o EAPC e foram observados individualmente, diretamente em uma caixa de vidro e em um campo aberto. Com relação ao grupo controle, animais tratados com EAPC apresentaram: aumento de roer, tremores, decréscimo da locomoção e do levantar após 29-38 min e nenhuma alteração na auto-limpeza. Além disso, foram observadas diferenças quanto ao gênero, sendo

  14. Diversidad y distribución de los moluscos de agua dulce en la Comunidad de Madrid (España

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    Soler, J.

    2006-05-01

    Full Text Available In this study of freshwater molluscs carried out in Comunidad de Madrid we cite the presence of 33 species, of which 25 are gastropods and eight bivalves. Twentythree of these species were previously reported in this area although most of them with different names either because they are synonyms or because they were determinated erronoeusly. The 33 species were identified from a total of 463 samples together with the specimens preserved at the Museo Nacional de Ciencias Naturales. Taxonomical data and short descriptions, as well as information about the habitats in which they were found is given for the 33 species. We also indicate if they were previously reported in the area and names given by authors. According to the bibliographic data used, a total of nine species are cited for the first time in the region: Pseudamnicola (Pseudamnicola subproducta, Pseudamnicola (Corrosella hinzi; Lymnaea stagnalis; Stagnicola palustris; Gyraulus (Gyraulus chinensis, Gyraulus (Torquis laevis, Ferrissia (Pettancylus clessiniana, Oxyloma (Oxyloma sarsii and Pisidium subtruncatum. Among the previous records, it is worth mentioning that it was not possible to locate “Islamia”coronadoi, Anisus (Disculifer vortex and Segmentina nitida. Stagnicola palustris, is reported for the first time although only shells were found. Two species, Potamopyrgus antipodarum and Gyraulus chinensis, are alien species. The first of those two species is considered as invasive and presents a wide distribution. Although Lymnaea stagnalis and Oxyloma (Oxyloma sarsii were only observed in a garden center, we cite them here because there is the possibility that they might accidentally spread out into natural habitats of the region.

    El estudio de los moluscos de agua dulce llevado a cabo en la Comunidad de Madrid permite citar 33 especies, de ellas 25 son de gasterópodos y ocho son de bivalvos. De estas especies, 23 ya hab

  15. Biological Mode of Action of Dimethomorph on Pseudoperonospora cubensis and Its Systemic Activity in Cucumber

    Institute of Scientific and Technical Information of China (English)

    WANG Han-cheng; ZHOU Ming-guo; WANG Jian-xin; CHEN Chang-jun; LI Hong-xia; SUN Hai-yan

    2009-01-01

    Dimethomorph is a fungicide with high activity against Peronosporomycetes plant pathogens. The present study showed that dimethomorph is effective on controlling the oomycete fungal pathogen Pseudoperonospora cubensis causing downy mildew on cucumber. The fungicide did not affect zoospores discharge from sporangia of P. cubensis, but it strongly inhibited mycelial growth and sporangial production in vitro and increased lysis of zoospores. Dose of 2 mg L-1 of dimethomorph was sufficient to inhibit mycelial growth and sporangial production of P. cubensis on leaf disks, 5 mg L-1 was enough to lyse zoospores of P. cubensis, and 25 mg L-1 was required to inhibit sporangial production on detached leaves. In whole plant tests, dimethomorph exhibited strong protective and curative activity. Dimethomorph when applied at a dose of 300 mg L-1 for 1, 3, 5, 7 days before inoculation exhibited 100% efficacy on disease control. Onthe other hand, efficacies of 67.1 and 31.5% were obtained when the same dose of dimethomorph was applied for 1 and 3 days after inoculation, respectively. So dimethomorph had persistence effect on leaves for 7 days at least and exhibited strong protective and curative activity. Bioassay analyses showed that dimethomorph could be translocated in the xylem system, redistributed in the leaf, and penetrated from the upper surface to the lower surface of the leaf but could not be translocated in phloem system or transferred from the roots to leaves of cucumber plants in sufficient amounts for disease control. The biocharacteristics of dimethomorph make it well suitable for integration of a control programme against downy mildew disease on cucumber and as a component to delay other peronosporomycetes fungicide-resistance development.

  16. Identification and transcriptional profiling of differentially expressed genes associated with resistance to Pseudoperonospora cubensis in cucumber.

    Science.gov (United States)

    Li, Jian-Wu; Liu, Jun; Zhang, He; Xie, Cong-Hua

    2011-03-01

    To identify genes induced during Pseudoperonospora cubensis (Berk. and Curk.) Rostov. infection in cucumber (Cucumis sativus L.), the suppression subtractive hybridization (SSH) was performed using mixed cDNAs prepared from cucumber seedlings inoculated with the pathogen as a tester and cDNA from uninfected cucumber seedlings as a driver. A forward subtractive cDNA library (FSL) and a reverse subtractive cDNA library (RSL) were constructed, from which 1,416 and 1,128 recombinant clones were isolated, respectively. Differential screening of the preferentially expressed recombinant clones identified 58 unique expressed sequence tags (ESTs) from FSL and 29 from RSL. The ESTs with significant protein homology were sorted into 13 functional categories involved in nearly the whole process of plant defense such as signal transduction and cell defense, transcription, cell cycle and DNA processing, protein synthesis, protein fate, proteins with binding functions, transport, metabolism and energy. The expressions of twenty-five ESTs by real-time quantitative RT-PCR confirmed that differential gene regulation occurred during P. cubensis infection and inferred that higher and earlier expression of transcription factors and signal transduction associated genes together with ubiquitin/proteasome and polyamine biosynthesis pathways may contribute to the defense response of cucumber to P. cubensis infection. The transcription profiling of selected down-regulated genes revealed that suppression of the genes in reactive oxygen species scavenging system and photosynthesis pathway may inhibit disease development in the host tissue.

  17. The effects of Tarantula cubensis venom on open wound healing in rats.

    Science.gov (United States)

    Gul Satar, N Y; Cangul, I T; Topal, A; Kurt, H; Ipek, V; Onel, G I

    2017-02-02

    The aim of this study was to evaluate the clinical and histopathological effects of two different dosages of alcohol extract of Tarantula cubensis (Theranekron) on open wounds. A total of 24 Sprague-Dawley rats were randomly divided into Tarantula cubensis extract (TCE1, n=8) 1/10 diluted, TCE (TCE2, n=8), and (3) vehicle-control (0.2 ml of 96 % ethanol, n=8) groups. Experimental full-thickness 1 x 1cm wounds were created on dorsum skin. TCE or vehicle were given systemically by subcutaneous injections on postoperative days 1 and 4. Wound planimetry and procurement of biopsies was performed on days 4, 8, 12 and 16. The mean non-epithelialised wound area in the vehicle-control group was significantly larger than in the TCE1 group on days 4, 8, 12 and 16, and in the TCE2 group on days 8, 12 and 16 (pwound contraction was significantly higher in the TCE1 and TCE2 groups than in the vehicle control group on days 8, 12 and 16 (pwound healing was characterised by a significant decrease in the neutrophil counts and a significant increase in neovascularisation; neither were effected by TCE. Our results suggest that alcohol extract of Tarantula cubensis accelerates epithelialisation and, thus, has beneficial effects on open wound healing in rats.

  18. Synonymy between Lymnaea bogotensis Pilsbry, 1935 and Lymnaea cousini Jousseaume, 1887 (Gastropoda: Lymnaeidae

    Directory of Open Access Journals (Sweden)

    Luz Elena Velásquez

    2006-11-01

    Full Text Available The lymneid snail Lymnaea bogotensis Pilsbry 1935 is synonymized with L. cousini Jousseaume 1887, based on morphological comparisons of the reproductive systems. The shell, renal tube, and reproductive system are described and illustrated from specimens collected in the type locality and the municipality of Paipa, Colombia. Bibliographical records reveal L. columella to be the commonest lymneid in the country. The latter two species can be differentiated based on the morphology of the penial complex.

  19. Haemolymph Components of Infected & None Infected Lymnaea Snails with Xiphidiocercariae

    OpenAIRE

    AA Saboor Yaraghi; A. Farahnak; MR Eshraghian

    2011-01-01

    Background: In this study the haemolymph components of infected and none infected Lymnaea gedrosiana with xiphidiocercaria larvae was compared.Methods: Five hundred Fifty Lymnaea snails were collected from Ilam and Mazandaran prov­inces, Iran, during 2008-2009. The snails were transported to the lab at Tehran University of Medi­cal Sciences and their cercarial sheddings were studied. Haemolmyphs of snails were ex­tracted and cells were counted using haemocytometer and cell-surface carbohydrat...

  20. Estado actual del conocimiento de los moluscos acuáticos en el Perú

    Directory of Open Access Journals (Sweden)

    Carlos Paredes

    2014-06-01

    Full Text Available Se revisa los antecedentes y el estado actual del conocimiento, acerca de los moluscos acuáticos en el Perú. Los moluscos marinos y dulceacuícolas se tratan separadamente, y se da información sobre el número de familias, géneros y especies conocidas, su distribución geográfica y estado de su conservación y utilización por el hombre. Se incluye listas actualizadas de las especies.

  1. Estudo morfométrico da concha de Lymnaea columella say, 1817 (Mollusca, Gastropoda, Pulmonata

    Directory of Open Access Journals (Sweden)

    Marlene T. Ueta

    1980-12-01

    Full Text Available Foram estudadas variações morfométricas de conchas de L. columella, provenientes de dez criadouros localizados nos seguintes municípios do Estado de São Paulo: - Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. Foram analisados os diferentes tipos de ambientes onde as limneas são encontradas com maior freqüência, estabelecendo-se a época do ano com maior abundância em espécimes, que correspondeu aos meses de julho a outubro. As medidas nas conhas dos diferentes criadouros referiram-se ao comprimento e largura da concha, comprimento e largura da abertura, comprimento da espira e número de voltas. Foram estabelecidos os coeficientes de correlação e de regressão e realizadas análises de variância entre as medidas tomadas e os índices obtidos da relação entre largura/comprimento da concha. Estas conchas foram comparadas com as de L. columella, L. viator, L. cubensis da coleção do Museu Nacional do Rio de Janeiro. Para a maioria das medidas as conchas mostraram proporções constantes, embora apresentassem diferenças em relação ao desenvolvimento. A maior variação foi observada em relação ao comprimento da espira. As variações morfométricas das conchas foram relacionadas com alguns fatores externos como pH, alcalinidade, dureza e teor da água. Aparentemente apenas a dureza total da água influiu na consistência das conchas.Shells of Lymnaea columella from ten populations from the State of São Paulo were studied to determine morphometric variation. Samples were collected in the following municipalities: Campinas, Americana, Atibaia, Pirassununga, Caçapava and Taubaté. Five measurements were taken from each shell: length and width of the shell, length and width of the aperture and lenght of the spire. Two ratios were also established: width/lenght of the shell and length of the aperture /length of the shell. The numbers of whorls and the length of the shell were also determined. Statistical tests

  2. Fasciola hepatica in Cuba: compatibility of different isolates with two intermediate snail hosts, Galba cubensis and Pseudosuccinea columella.

    Science.gov (United States)

    Vázquez, A A; Sánchez, J; Pointier, J-P; Théron, A; Hurtrez-Boussès, S

    2014-12-01

    In Cuba, only two lymnaeid snails, Galba cubensis and Pseudosuccinea columella, with different ecology and distribution patterns, are intermediate hosts for Fasciola hepatica. The compatibility of these two species as hosts was analysed through their rates of infection, the production of rediae and survivorship when exposed to F. hepatica miracidia. Ten populations of G. cubensis, eight of P. columella collected from various habitats and six isolates of F. hepatica sampled in slaughterhouses from different localities were tested. Our results clearly demonstrate that G. cubensis is a more compatible host for F. hepatica in Cuba when compared with P. columella. However, the role that P. columella may have in fascioliasis transmission under certain conditions should not be disregarded. Variation in infectivity among isolates of F. hepatica were also observed and may explain why some regions in Cuba are more commonly subjected to fascioliasis outbreaks.

  3. Efeito moluscicida do óleo essencial de Cymbopogon winterianus Jowitt (Poaceae sobre Lymnaea columella (Say, 1817 e Biomphalaria tenagophila(D’Orbigny, 1835

    Directory of Open Access Journals (Sweden)

    A.V. COSTA

    2015-01-01

    Full Text Available RESUMO O uso das substâncias moluscicidas convencionais no controle de planorbídeos vetores constitui-se uma importante ferramenta no combate da fasciolose hepática e esquistossomose. Sendo, portanto, de extrema relevância para a pecuária e para os serviços de Vigilância Epidemiológica. Por outro lado, a seleção de caramujos resistentes a tais substâncias e sua baixa seletividade estimulam a busca por novas substâncias. Neste sentido, o presente trabalho foi desenvolvido para avaliar o efeito do óleo essencial de Cymbopogon winterianusJowitt sobre Lymnaea columella e Biomphalaria tenagophila, hospedeiros intermediários de Fasciola hepatica e esquistossomose mansônica, respectivamente. O óleo essencial foi extraído a partir de folhas frescas utilizando o sistema Clevenger. A análise qualitativa foi realizada por meio de cromatografia gasosa acoplada a espectrometria de massas (CG/EM e a quantificação dos constituintes presentes no óleo foi determinada por cromatografia gasosa acoplada ao detector de ionização de chama (CG/DIC. O efeito moluscicida foi avaliado utilizando seis moluscos de cada espécie e o óleo essencial de C. winterianus nas concentrações finais de 10, 20, 30, 40, 60, 80 e 100 ppm. A análise por cromatografia gasosa do óleo essencial possibilitou a identificação dos componentes majoritários geraniol (28,62%, citronelal (23,62% e citronelol (17,10%. Os valores de DL100 e DL50para os moluscos das espécies L. columella e B. tenagophila foram, respectivamente, 60 e 40 ppm; 80 ppm e 60 ppm. O óleo de Cymbopogon winterianus demonstrou-se uma alternativa promissora para o controle dos moluscos, sendo a espécie L. columella mais sensível ao mesmo.

  4. PCR diagnosis of Fasciola hepatica in field-collected Lymnaea columella and Lymnaea viatrix snails.

    Science.gov (United States)

    Cucher, Marcela A; Carnevale, Silvana; Prepelitchi, Lucila; Labbé, Jorge H; Wisnivesky-Colli, Cristina

    2006-04-15

    Fasciolosis, caused by the trematode Fasciola hepatica, is a zoonosis of economic importance in livestock that is emerging as a chronic disease in humans. The intermediate hosts are lymnaeid snails, in which diagnosis of infection is traditionally based on cercarial shedding, tissue sectioning and crushing. We developed a PCR assay for the sensitive and specific detection of F. hepatica in field-collected Lymnaea sp. snails. A primer pair was designed to amplify a 405 bp fragment of the cytochrome c oxidase subunit 1 gene of F. hepatica. The PCR assay showed a limit of detection of 10 pg of genomic F. hepatica DNA. No cross-reactions were observed with samples from other related trematode species or from the snail hosts Lymnaea columella and Lymnaea viatrix. DNA sequencing of the amplicon showed 100% homology with F. hepatica, and 75-89% homology with other trematodes on regions that did not include the entire set of primers. Two samples from Argentina were analysed. For snails in sample 1 (n = 240), identified as L. columella, the infection rate was 17.5 and 51.3% by direct examination and PCR, respectively. For snails in sample 2 (n = 34), identified as L. viatrix, the infection rate was 2.9 and 61.8% by direct examination and PCR, respectively. Differences in infection rates between these diagnosis methods were significant for both samples. Our PCR technique showed to be effective for detecting specific F. hepatica infections of low intensity in the intermediate host, and hence it could be used to study the epidemiological situation in a given area, as well as to assess host suitability for the parasite.

  5. [Anatomy and morphometry of Physa cubensis Pfeiffer, 1839 (Pulmonata: Physidae) in Cuba].

    Science.gov (United States)

    Cong, M Y; Ferrer López, J R; Perera de Puga, G

    1994-01-01

    The anatomic description of Physa cubensis, based on specimens collected in 5 different sites in Cuba, is presented. The anatomic characteristics of the reproductive system as well as mantle digitations give ground for affirming that this is a unique species with external morphological variations and thus it should be kept under the Physa genre. Besides, dispersion diagrams and regression lines of the length in the width were analyzed in the five sites; the L/A (length/width) variation quotient was compared using a variance analysis. Significant differences were observed in the different sites probably due to the feeding sources of each biotope.

  6. Moluscos y paleoambientes del Pleistoceno tardío - Holoceno en la cuenca media e inferior del Río Salado, provincia de Buenos Aires

    OpenAIRE

    Pisano, María Florencia

    2015-01-01

    Los moluscos son componentes principales tanto de las comunidades dulceacuícolas modernas, como de los depósitos continentales cuaternarios. Las investigaciones paleontológicas sobre moluscos realizadas en ámbitos continentales, se encuentran sesgadas hacia ambientes lénticos (lagos y lagunas), mientras que la fauna de los ambientes fluviales ha sido menos estudiada. El objeto de estudio de esta tesis fueron, los ensambles de moluscos continentales cuaternarios de la cuenca media e inferior d...

  7. A multiplex PCR for the detection of Fasciola hepatica in the intermediate snail host Galba cubensis.

    Science.gov (United States)

    Alba, Annia; Vázquez, Antonio A; Hernández, Hilda; Sánchez, Jorge; Marcet, Ricardo; Figueredo, Mabel; Sarracent, Jorge; Fraga, Jorge

    2015-07-30

    Fasciolosis is a snail-borne trematode infection that has re-emerged as a human disease, and is considered a significant problem for veterinary medicine worldwide. The evaluation of the transmission risk of fasciolosis as well as the efficacy of the strategies for its control could be carried out through epidemiological surveillance of the snails that act as intermediate hosts of the parasites. The present study aimed to develop the first multiplex PCR to detect Fasciola hepatica in Galba cubensis, an important intermediate host of the parasite in the Americas and especially in the Caribbean basin. The multiplex PCR was optimized for the amplification of a 340 bp fragment of the second internal transcribed spacer (ITS-2) of F. hepatica rDNA, while another set of primers was designed and used to amplify a conserved segment of the nuclear 18S rDNA of the snail (451 bp), as an internal control of the reaction. The assay was able to detect up to 100 pg of the parasite even at high concentrations of snail DNA, an analytical sensitivity that allows the detection of less than a single miracidium, which is the minimal biological infestation unit. A controlled laboratory-reared G. cubensis - F. hepatica system was used for the evaluation of the developed multiplex PCR, and 100% sensitivity and specificity was achieved. This assay constitutes a novel, useful and suitable technique for the survey of fasciolosis transmission through one of the main intermediate hosts in the Western hemisphere.

  8. The effect of particle size on the leaching of Scirpus cubensis Poepp & Kunth

    Directory of Open Access Journals (Sweden)

    Bianchini Jr. I.

    2003-01-01

    Full Text Available An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão. Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities.

  9. Estratigrafía de los Moluscos Marinos en los Yacimientos Prehistóricos Vascos.

    OpenAIRE

    1990-01-01

    La presencia de moluscos marinos en los yacimientos vascos es patente desde el Musteriense hasta los niveles con cerámica. En el presente trabajo se ha tratado de plasmar la evolución del marisqueo y su significado, intentando establecer consideraciones de tipo cultural, climático..., conscientes del bajo número de yacimientos en que la malacofauna ha sido estudiada detalladamente.

  10. Estratigrafía de los Moluscos Marinos en los Yacimientos Prehistóricos Vascos.

    Directory of Open Access Journals (Sweden)

    Marga Imaz

    1990-01-01

    Full Text Available La presencia de moluscos marinos en los yacimientos vascos es patente desde el Musteriense hasta los niveles con cerámica. En el presente trabajo se ha tratado de plasmar la evolución del marisqueo y su significado, intentando establecer consideraciones de tipo cultural, climático..., conscientes del bajo número de yacimientos en que la malacofauna ha sido estudiada detalladamente.

  11. Reproductive data of Squalus cubensis collected from Gulf of Mexico from 2005-01-10 to 2012-12-03 (NCEI Accession 0150633)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Reproductive data from Squalus cubensis (Cuban dogfish) were opportunistically collected from 2005-2012. Data include those necessary to examine reproductive cycle,...

  12. Lymnaea cousini Jousseaume, 1887, from Ecuador (Gastropoda: Lymnaeidae

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1995-10-01

    Full Text Available A description is given of the shell, renal organ, reproductive system and radula of topotypic specimens of Lymnaea cousini Jousseaume, 1887. A diagnosis between it and four other lymnaeids which also occur in South America and were previously studied by the author (L. columella, L. diaphana, L. viatrix and L. rupestris is presented.

  13. La Historia de una especie del patrimonio holguinero: Escobaria cubensis (Cactaceae "el cactus enano". Primera parte

    Directory of Open Access Journals (Sweden)

    Alena Reyes Fornet

    2010-01-01

    Full Text Available Presenta una investigación sobre la historia taxonómica y estudios sobre la ecología del "cactus enano de Holguín", Escobaria cubensis (Britton & Rose Hunt, 1978 desde 1909 hasta 1990, elementos importantes, para la conservación y como contribución al conocimiento de la historia del patrimonio natural holguinero, con datos históricos sobre visitas de personalidades del mundo y Holguín. Se estudiaron 37 materiales correspondientes a notas de viajes, cartas y publicaciones. Se señala la posibilidad de que el colector, J. Shafer estuvo en dos zonas de distribución. Las contribuciones al conocimiento de su ecología hasta 1990 se basaron en la observación y descripción.

  14. Phytochemical characterization of the threatened specie Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi

    Directory of Open Access Journals (Sweden)

    Mabelkis Terry Rosabal

    2016-04-01

    Full Text Available Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi is commonly known as buffalo, represents an endemic subspecies and categorized as critical danger of extinction in Cuba. This work aimed to characterize the phytochemical composition of plants of F. caroliniana in two localities of the Matanzas province. The presence of secondary metabolites in leaf extracts was qualitatively analyzed and reductive and total sugars were quantified. The results indicated the presence of flavonoids, terpenes, steroids, saponins, tannins and anthraquinones in leaves that could be considered for further systematic studies and application in agriculture. The plants from the Ciénaga de Zapata showed contents of reducing sugars and totals higher than those obtained in the plants of Martí. These results provide information for the identification of characters of possible taxonomic and conservation value in this species.   Keywords: anthraquinons, extracts, swamp ash, steroids, tannins, terpens

  15. Epidemiology and population biology of Pseudoperonospora cubensis: a model system for management of downy mildews.

    Science.gov (United States)

    Ojiambo, Peter S; Gent, David H; Quesada-Ocampo, Lina M; Hausbeck, Mary K; Holmes, Gerald J

    2015-01-01

    The resurgence of cucurbit downy mildew has dramatically influenced production of cucurbits and disease management systems at multiple scales. Long-distance dispersal is a fundamental aspect of epidemic development that influences the timing and extent of outbreaks of cucurbit downy mildew. The dispersal potential of Pseudoperonospora cubensis appears to be limited primarily by sporangia production in source fields and availability of susceptible hosts and less by sporangia survival during transport. Uncertainty remains regarding the role of locally produced inoculum in disease outbreaks, but evidence suggests multiple sources of primary inoculum could be important. Understanding pathogen diversity and population differentiation is a critical aspect of disease management and an active research area. Underpinning advances in our understanding of pathogen biology and disease management has been the research capacity and coordination of stakeholders, scientists, and extension personnel. Concepts and approaches developed in this pathosystem can guide future efforts when responding to incursions of new or reemerging downy mildew pathogens.

  16. Potential of Hemianax ephippiger (Odonata-Aeshnidae) nymph as predator of Fasciola intermediate host, Lymnaea natalensis

    National Research Council Canada - National Science Library

    Aly Younes Hanaa El-Sherif Fathia Gawish Marwa Mahmoud

    2015-01-01

    Objective: To evaluate the predatory capacity of the Odonata, Hemianax ephippiger nymph as a biocontrol agent for the freshwater snail Lymnaea natalensis, intermediate host of Fasciola gigantica. Methods...

  17. Phytochemical characterization of the threatened specie Fraxinus caroliniana Mill subsp. cubensis (Griseb.) Borhidi

    OpenAIRE

    Mabelkis Terry Rosabal; Beatriz del Valle Suárez; Yunel Pérez Hernández; Ileana Mestre Naite; Yohanka Lezcano Mas; Lenia Robledo Ortega

    2016-01-01

    Fraxinus caroliniana Mill subsp. cubensis (Griseb.) Borhidi is commonly known as buffalo, represents an endemic subspecies and categorized as critical danger of extinction in Cuba. This work aimed to characterize the phytochemical composition of plants of F. caroliniana in two localities of the Matanzas province. The presence of secondary metabolites in leaf extracts was qualitatively analyzed and reductive and total sugars were quantified. The results indicated the presence of flavonoids, te...

  18. Synaptic metaplasticity underlies tetanic potentiation in Lymnaea: a novel paradigm

    CERN Document Server

    Mehta, Anita; Luk, Collin C; Syed, Naweed I

    2013-01-01

    We present a mathematical model which explains and interprets a novel form of short-term potentiation, which was found to be use-, but not time-dependent, in experiments done on Lymnaea neurons. The high degree of potentiation is explained using a model of synaptic metaplasticity, while the use-dependence (which is critically reliant on the presence of kinase in the experiment) is explained using a model of a stochastic and bistable biological switch.

  19. Synaptic metaplasticity underlies tetanic potentiation in Lymnaea: a novel paradigm.

    Directory of Open Access Journals (Sweden)

    Anita Mehta

    Full Text Available We present a mathematical model that explains and interprets a novel form of short-term potentiation, which was found to be use-, but not time-dependent, in experiments done on Lymnaea neurons. The high degree of potentiation is explained using a model of synaptic metaplasticity, while the use-dependence (which is critically reliant on the presence of kinase in the experiment is explained using a model of a stochastic and bistable biological switch.

  20. El consumo de moluscos en la Costa Norte de Santa Cruz

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Zubimendi

    2005-12-01

    Full Text Available En este trabajo se discute el valor de los moluscos en las dietas indígenas de los grupos que ocuparon la Costa Norte de Santa Cruz durante el Holoceno tardío, por medio del potencial alimenticio de los mismos, inferido a partir del análisis del registro arqueológico superficial. Se discute, de esta manera, la imagen arqueológica construida a partir de análisis previos, a la luz de los nuevos resultados centrados en los restos malacológicos. Se considera que la densidad de restos de moluscos en los sitios arqueológicos refleja la importancia dietaria relativa de los mismos. Por ello, se tiene en cuenta la variabilidad de especies de moluscos representados arqueológicamente, cuya presencia presumiblemente, responde a decisiones antrópicas orientadas al consumo alimenticio. Por último, se analiza el aporte calórico estimado por especie en el nivel areal. Dado que es imposible establecer valores absolutos para el aporte calórico total representado en cada sitio, se trabaja con porcentajes relativos como aproximación al aporte diferencial de los moluscos a la dieta indígena. Esta metodología exploratoria y experimental, es una herramienta sencilla y operativa de análisis, que permitirá hacer un aporte inicial, para tratar de responder parcialmente a los interrogantes, así como para discutir algunas conclusiones a las que se han arribado previamente.In this paper the value of mussels in the hunter-gatherer diet of the northern coast of Santa Cruz in the Late Holocene is discussed through the alimentary potential inferred from the archaeological record. As such, the archaeological image constructed from previous analyses is discussed in light of new results obtained from the analysis of the mussel remains. The density of mussel shell reflects the relative dietary importance of this resource. In relation to that idea we considered the variability of species represented archaeologically, the presence of which presumably represents the

  1. Lymnaea viatrix and Lymnaea columella in the neotropical region: a distributional outline

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1982-06-01

    Full Text Available A review of lymnaeid samples collected by the author from 106 localities in Mexico, Cuba, Jamaica, Haiti, Dominican Republic, Puerto Rico, Martinique, Saint Lucia, Guatemala, Costa Rica, Panamá, Ecuador, Peru, Bolivia, Chile, Argentina, Uruguay andBrazil showed that one of them (from Ecuador belonged to Lymnaea cousini Jousseaume, 1887, and all the others to either L. viatrix Orbigny, 1835 or l. columella Say, 1817. The ranges of L. viatrix and L. columella overlap in Middle America, and in northern and southern South America (Venezuela-Colombia-Ecuador and northeastern Argentina-Uruguay-southernmost Brazil, respectively. L. viatrix was the only species found in Peru west of the Andes and in Chile, and is supposed to have migrated eastward to Argentina via the Negro river basin. The range of L. columella in South America is discontinuous. The species has been recorded from Venezuela, Colombia and Ecuador and, east of the Andes, from latitudes 15º S (central-west Brazil to 35º S (La Plata, Argentina. Such a gap may be attributed to either introduction from the northern into the southern area, or migration along the unsampled region on the eastern side of the Andes, or extinction in the now vacant area. No lymnaeids have been found so far in Brazil north of latitude 15º S and in the Guianas.A revisão de amostras de limneídeos coletados pelo autor em 106 localidades no México, Cuba, Jamaica, Haiti, República Dominicana, Porto Rico, Martinica, Santa Lúcia, Guatemala, Costa Rica, Panamá, Equador, Peru, Bolívia, Chile, Argentina, Uruguai e Brasil mostrou que uma delas (do Equador pertencia a Lymnaea cousini Jousseaume, 1887, e que todas as outras pertenciam a L. viatrix Orbigny, 1835 ou a L. columella Say, 1817. As distribuições da L. viatrix e da l. columella sobrepõem-se na Meso-América e na América do Sul setentrional (Venezuela-Colômbia-Equador e meridional (nordeste da Argentina-Uruguai-extremo sul do Brasil. A L. viatrix foi a

  2. Estudo do crescimento de moluscos pertencentes a populações de Biomphalaria glabrata e B. tenagophila

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1969-01-01

    Full Text Available Os autores estudam, comparativamente o crescimento de duas populações de moluscos planorbídeos pertencentes às espécies B. glabrata e B. tenagophila. Concluem que não há diferença significativa entre o crescimento dos caramujos oriundos das populações estudadas.

  3. Expression profiling of Cucumis sativus in response to infection by Pseudoperonospora cubensis.

    Science.gov (United States)

    Adhikari, Bishwo N; Savory, Elizabeth A; Vaillancourt, Brieanne; Childs, Kevin L; Hamilton, John P; Day, Brad; Buell, C Robin

    2012-01-01

    The oomycete pathogen, Pseudoperonospora cubensis, is the causal agent of downy mildew on cucurbits, and at present, no effective resistance to this pathogen is available in cultivated cucumber (Cucumis sativus). To better understand the host response to a virulent pathogen, we performed expression profiling throughout a time course of a compatible interaction using whole transcriptome sequencing. As described herein, we were able to detect the expression of 15,286 cucumber genes, of which 14,476 were expressed throughout the infection process from 1 day post-inoculation (dpi) to 8 dpi. A large number of genes, 1,612 to 3,286, were differentially expressed in pair-wise comparisons between time points. We observed the rapid induction of key defense related genes, including catalases, chitinases, lipoxygenases, peroxidases, and protease inhibitors within 1 dpi, suggesting detection of the pathogen by the host. Co-expression network analyses revealed transcriptional networks with distinct patterns of expression including down-regulation at 2 dpi of known defense response genes suggesting coordinated suppression of host responses by the pathogen. Comparative analyses of cucumber gene expression patterns with that of orthologous Arabidopsis thaliana genes following challenge with Hyaloperonospora arabidopsidis revealed correlated expression patterns of single copy orthologs suggesting that these two dicot hosts have similar transcriptional responses to related pathogens. In total, the work described herein presents an in-depth analysis of the interplay between host susceptibility and pathogen virulence in an agriculturally important pathosystem.

  4. Expression profiling of Cucumis sativus in response to infection by Pseudoperonospora cubensis.

    Directory of Open Access Journals (Sweden)

    Bishwo N Adhikari

    Full Text Available The oomycete pathogen, Pseudoperonospora cubensis, is the causal agent of downy mildew on cucurbits, and at present, no effective resistance to this pathogen is available in cultivated cucumber (Cucumis sativus. To better understand the host response to a virulent pathogen, we performed expression profiling throughout a time course of a compatible interaction using whole transcriptome sequencing. As described herein, we were able to detect the expression of 15,286 cucumber genes, of which 14,476 were expressed throughout the infection process from 1 day post-inoculation (dpi to 8 dpi. A large number of genes, 1,612 to 3,286, were differentially expressed in pair-wise comparisons between time points. We observed the rapid induction of key defense related genes, including catalases, chitinases, lipoxygenases, peroxidases, and protease inhibitors within 1 dpi, suggesting detection of the pathogen by the host. Co-expression network analyses revealed transcriptional networks with distinct patterns of expression including down-regulation at 2 dpi of known defense response genes suggesting coordinated suppression of host responses by the pathogen. Comparative analyses of cucumber gene expression patterns with that of orthologous Arabidopsis thaliana genes following challenge with Hyaloperonospora arabidopsidis revealed correlated expression patterns of single copy orthologs suggesting that these two dicot hosts have similar transcriptional responses to related pathogens. In total, the work described herein presents an in-depth analysis of the interplay between host susceptibility and pathogen virulence in an agriculturally important pathosystem.

  5. Haemolymph Components of Infected & None Infected Lymnaea Snails with Xiphidiocercariae

    Directory of Open Access Journals (Sweden)

    AA Saboor Yaraghi

    2011-03-01

    Full Text Available Background: In this study the haemolymph components of infected and none infected Lymnaea gedrosiana with xiphidiocercaria larvae was compared.Methods: Five hundred Fifty Lymnaea snails were collected from Ilam and Mazandaran prov­inces, Iran, during 2008-2009. The snails were transported to the lab at Tehran University of Medi­cal Sciences and their cercarial sheddings were studied. Haemolmyphs of snails were ex­tracted and cells were counted using haemocytometer and cell-surface carbohydrate were recog­nized by conjugated lectin (Lentil. Haemolymph protein concentrations were measured by Brad­ford protein assay method and soluble protein compositions were determined on sodium dodecyl sulphate polyacrilamide gel electrophoresis (SDS-PAGE.Result: From the 550 examined Lymnaea snails for cercariae, 27 snails were infected with xiphidiocer­cariae. Mean of haemolymph cells (haemocyte number were obtained 93480±2.43 (cells/ml for none infected snails (25 snail and 124560±2800 (cells/ml for infected snails (25 snail. Mannose carbohydrate was recognized on haemocyte of none infected and infected snails. Mean of protein concentration of haemolymph plasma was obtained as 1354 ± 160 μg/ml (1.4 mg/ml for none infected snails (25 snails and 1802±138 μg/ml (1.8 mg/ml for infected snail (25 snails. Comparing to none infected snails, the SDS-PAGE results of haemolymph plasma of infected snails, showed an extra protein band (70 kDa. The results showed a significant differ­ence between the amounts and the kinds of proteins in haemolymph of infected and none infected snails.Conclusion: This information might be useful to understand of parasite detection, adhesion, engulf­ment and antigen agglutination by snail.

  6. Lymnaea palustris and Lymnaea fuscus are potential but uncommon intermediate hosts of Fasciola hepatica in Sweden.

    Science.gov (United States)

    Novobilský, Adam; Kašný, Martin; Beran, Luboš; Rondelaud, Daniel; Höglund, Johan

    2013-08-29

    Lymnaea palustris and L. fuscus are members of the European stagnicolines (Gastropoda: Lymnaeidae). The role of stagnicolines in transmission of Fasciola hepatica has been often proposed. To assess the possible relationship between these two stagnicolines and F. hepatica in Sweden, field monitoring in parallel with experimental infections of L. palustris and L. fuscus were conducted. Stagnicoline snails were collected and identified on pastures grazed by either sheep or cattle on four farms suffering from fasciolosis in Sweden during 2011-2012. Field-collected L. palustris and L. fuscus were examined for F. hepatica DNA by PCR. In the laboratory, different age groups of L. palustris, L. fuscus and G. truncatula were each exposed to two F. hepatica miracidia and main infection characteristics were obtained. One field-collected L. palustris (out of n = 668) contained F. hepatica as determined by PCR. On the other hand, stagnicolines artificially exposed to F. hepatica miracidia resulted in successful infection with fully differentiated cercariae, but only in juvenile snails (size, 1-2 mm at exposure) and with a prevalence of 51% and 13% in L. palustris and L. fuscus, respectively. In contrast, 90% of juvenile (size, 1-2 mm) and 92% of preadult G. truncatula (size, ≥ 2-4 mm), respectively, were successfully infected. Delayed, reduced and/or no spontaneous cercarial shedding was observed in the two stagnicolines when compared to G. truncatula. However, at snail dissection most cercariae from L. fuscus and L. palustris were able to encyst similarly to those from G. truncatula. Both L. fuscus and L. palustris can sustain larval development of F. hepatica but with an apparent level of age resistance. The finding of a single F. hepatica positive specimen of L. palustris, together with infection characteristics from the experimental infection, suggest that L. palustris is a more suitable snail vector of F. hepatica than L. fuscus. The reduced growth observed in both

  7. Aspectos básicos sobre la clasificación, recolección, toma de datos y conservación de los moluscos

    OpenAIRE

    Barrientos, Zaidett

    2016-01-01

    Los moluscos se dividen en 7 u 8 clases y aunque son bastante distintas entre si, algunas especies o grupos de especies podrían confundir a los principiantes en el estudio de este filo. A continuación encontrará una clave sencilla que le puede ayudar a ubicar en clases a los moluscos. Recomiendo utilizar las ilustraciones para una mejor comprensión de la clave.

  8. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier

    2016-01-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from...

  9. Estrogen-Related Fecundity Reduction of Lymnaea ollula Following Fasciola gigantica Infection

    National Research Council Canada - National Science Library

    Supeecha Kumkate; Nuttajit Onmek; Bongkoj Boonburapong; Sombut Singhakaew; Vijittra Leardkamolkarn

    2009-01-01

    .... Reduction in life expectancy and reproductive capacity have previously been documented in Fasciola gigantica-infected Lymnaea ollula, but the influence of the endocrine system on this specific host...

  10. Intermediate snail hosts of French Fasciola hepatica: Lymnaea neotropica and Lymnaea viatrix are better hosts than local Galba truncatula.

    Science.gov (United States)

    Sanabria, R; Mouzet, R; Courtioux, B; Vignoles, P; Rondelaud, D; Dreyfuss, G; Cabaret, J; Romero, J

    2012-11-01

    Allopatric and sympatric infections of Lymnaea neotropica and Lymnaea viatrix var. ventricosa with Argentinean and French isolates of Fasciola hepatica were carried out to determine the capacity of these snails to produce metacercariae and to verify if this capacity changed with snail generation. The same process was also made with a French population of Galba truncatula known to be highly susceptible to French isolates of the parasite. In each lymnaeid species separately considered, the survival rate at day 30 post-exposure and prevalence of F. hepatica infection in the group infected with Argentinean miracidia were significantly greater than those recorded in the corresponding French one. Compared to infected G. truncatula, both South American lymnaeids had longer patent periods and produced a higher number of metacercariae. The highest infections were noted with L. v. ventricosa. In the three snail species, metacercarial production was more important with the Argentinean isolate of miracidia than with the French one. If three successive generations of L. v. ventricosa are exposed to the same French isolate of miracidia, cercarial production significantly increased from parents to the F2 generation, while the other characteristics of infection only showed insignificant variations. L. neotropica and L. v. ventricosa are better intermediate hosts for French F. hepatica than local G. truncatula. The numerical increase of shed cercariae in the F1 and F2 generations of L. v. ventricosa demonstrates a rapid adaptation of this species to the French isolate of the parasite.

  11. Moluscos dulceacuícolas exóticos en Chile Exotic freshwater mollusks in Chile

    Directory of Open Access Journals (Sweden)

    Sergio Letelier V.

    2007-10-01

    Full Text Available Las especies de moluscos exóticas dulceacuícolas registradas en esta contribución, corresponden a ejemplares recolectados en humedales en acuarios comerciales o interceptados en barreras aduaneras, así como de referencias bibliográficas. Un total de 7 especies pertenecientes a 6 géneros fueron identificadas: Pomacea bridgesii; Helobia sp.; Thiara (Melanoides tuberculata; Melanoides maculata; Physa sp.; Physella venustula y Biomphalaria sp. Melanoides maculata fue recolectada en el río Lluta y clasificada como especie criptogénica. Los moluscos exóticos recolectados podrían tener éxito en su establecimiento si se considera la vulnerabilidad de los hábitats nativos debido al cambio en las condiciones climáticas globales o a las elevaciones térmicas producidas en el sector costero por los fenómenos de El Niño. En este sentido, las especies subtropicales observadas se podrían considerar como no endémicas y vectores potenciales de zoonosis parasitarias. Las principales vías de introducción de moluscos dulceacuícolas exóticos se derivaron del intercambio comercial, por lo cual, y frente a su incremento interregional, se hace necesario recopilar datos ecológicos y taxonómicos adecuados que permitan evaluar el riesgo de su establecimiento, así como servir de base para la aplicación de futuros tratamientos en bioseguridad.The exotic freshwater mollusk species we report here were collected in wetlands, commercial aquariums, or were given to us by government officials who intercepted some exotic species at customs offices. Other records came from the specialized literature. These species are Pomacea bridgesii; Helobia sp.; Thiara (Melanoides tuberculata; Melanoides maculata; Physa sp., Physella venustula and Biomphalaria sp. It is not clear how Melanoides maculata, found in the Río Lluta, reached Chile. The exotic species collected could expand their ranges in Chilean territory given global environmental and climate change or the

  12. Characterization of pre- and postsynaptic dopamine receptors in Lymnaea.

    Science.gov (United States)

    Audesirk, T E

    1989-01-01

    1. The effects of dopamine and several synthetic agonists and antagonists were studied using two identified neurons of the snail Lymnaea stagnalis. 2. In both the buccal-2 (B-2) neurons and the pedal giant (RPeD1) neuron dopamine elicited a hyperpolarizing response at least partly due to potassium efflux. RPeD1 is itself dopaminergic, implicating autoreceptors in its response to dopamine. 3. The following agents were tested: agonists--LY171555, pergolide, SKF38393, (-)-3-PPP, R(-)NPA and dopamine; antagonists--SCH23390, sulpiride, and metaclopramide. Dibutyryl cAMP was applied to determine whether the response is cAMP-mediated. 4. Results indicate that the pharmacological profiles of dopamine receptors on these neurons are inconsistent with those of either D-1, D-2 or autoreceptors in mammals.

  13. Estudo da correlação entre molusco contagioso e dermatite atópica em crianças

    OpenAIRE

    Seize,Maria Bandeira de Melo Paiva; Ianhez, Mayra; Cestari, Silmara da Costa Pereira [UNIFESP

    2011-01-01

    FUNDAMENTOS: É bastante divulgado, sem a fundamentação científica necessária, que a infecção por molusco contagioso tende a ser mais frequente e de maior intensidade nos pacientes acometidos por dermatite atópica. Tal fato motivou a realização deste trabalho. OBJETIVOS: Avaliar a prevalência de associação de dermatite atópica e molusco contagioso; avaliar se, nos pacientes com dermatite atópica, a infecção por molusco contagioso é mais recorrente e/ou disseminada e se a ocorrência de eczema p...

  14. Metabolitos secundarios, letalidad y actividad antimicrobiana de los extractos de tres corales y tres moluscos marinos de Sucre, Venezuela

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    Gabriel Ordaz

    2010-06-01

    Full Text Available A los extractos crudos de los octocorales Eunicea sp., Muricea sp. y Pseudopterogorgia acerosa y de los moluscos Pteria colymbus, Phylonotus pomum y Chicoreus brevifrons, se les realizaron pruebas químicas, las cuales evidenciaron en todos ellos, la presencia de metabolitos secundarios como alcaloides, esteroles insaturados y triterpenos pentacíclicos. Sólo se detectaron sesquiterpenlactonas, saponinas, taninos, glicósidos cianogénicos y glicósidos cardiotónicos en algunos de los extractos de los octocorales, lo cual sugiere que la biosíntesis de estos metabolitos es propia de este grupo de organismos. Asimismo, se evaluó la actividad letal y antimicrobiana de los extractos de los octocorales y moluscos. En el bioensayo de letalidad, todos los extractos resultaron letales frente al crustáceo Artemia salina (CL50<1.000μg/ml. La actividad letal incrementσ con el tiempo de exposiciσn. El extracto de P. pomum presentó la mayor actividad letal (CL50=46.8μg/ml. En los ensayos de actividad antimicrobiana, los extractos orgαnicos de los moluscos presentaron una mayor actividad y un espectro de acción mayor contra diferentes cepas de bacterias, respecto a los octocorales; aunque estos últimos también inhibieron el crecimiento de algunas cepas de hongos. Staphylococcus aureus, fue la bacteria más susceptible al poder antimicrobiano de los extractos (66.7%, mientras que la bacteria Pseudomonas aeruginosa y los hongos Candida albicans y Aspergillus niger, no fueron afectados. La antibiosis mostrada por los extractos de los diferentes invertebrados marinos estudiados, indica que algunos de los metabolitos biosintetizados por éstos son fisiológicamente activos con posible potencial citotóxico y/o antibiótico.

  15. Sustancias naturales de moluscos opistobranquios: estudio de su estructura, origen y función en ecosistemas bentónicos

    OpenAIRE

    Ávila Escartín, Conxita

    1993-01-01

    Los Moluscos Opistobranquios, en relación a la reducción o incluso pérdida de la concha, han desarrollado múltiples y sofisticados métodos de defensa (incluyendo la defensa química) que les han permitido sobrevivir sin dicha defensa mecánica. En esta Tesis se estudia el papel de las sustancias naturales de Moluscos Opistobranquios, haciendo énfasis en aspectos biológicos tales como el origen dietético o biosintético de las mismas, su localización en el organismo, y su actividad y función en e...

  16. Distribución y partición aditiva de la diversidad de las comunidades de moluscos de agua dulce en arroyos del Sur de Brasil.

    OpenAIRE

    2014-01-01

    La partición aditiva de la diversidad de especies es un enfoque prometedor para el análisis de los patrones de diversidad en las comunidades de moluscos, especialmente su distribución espacial. Nuestros objetivos fueron evaluar la distribución de las comunidades de moluscos en los arroyos en el Sur de Brasil, y evaluar la partición de diversidad de la comunidad en diferentes escalas espaciales. El muestreo se llevó a cabo en cuatro cuencas del curso inferior del río Toropi, Brasil. Todas las ...

  17. Translocation of mercury from substrate to fruit bodies of Panellus stipticus, Psilocybe cubensis, Schizophyllum commune and Stropharia rugosoannulata on oat flakes.

    Science.gov (United States)

    Gabriel, Jiří; Švec, Karel; Kolihová, Dana; Tlustoš, Pavel; Száková, Jiřina

    2016-03-01

    The cultivation and fructification of 15 saprotrophic and wood-rotting fungal strains were tested on three various semi-natural medium. The formation of fruit bodies was observed for Panellus stipticus, Psilocybe cubensis, Schizophyllum commune and Stropharia rugosoannulata in the frame of 1-2 months. Mercury translocation from the substrate to the fruit bodies was then followed in oat flakes medium. Translocation was followed for treatments of 0, 1.25, 2.5, 5, 10 and 20ppm Hg in the substrate. All four fungi formed fruit bodies in almost all replicates. The fruit body yield varied from 0.5 to 15.3g dry weight. The highest bioconcentration factor (BCF) of 2.99 was found for P. cubensis at 1.25ppm Hg. The BCF decreased with increasing Hg concentration in the substrate: 2.49, 0, 2.38, 1.71 and 1.82 for P. stipticus; 3.00, 2.78, 2.48, 1.81 and 2.15 for P. cubensis; 2.47, 1.81, 1.78, 1.07 and 0.96 for S. commune; and 1.96, 1.84, 1.21, 1.71 and 0.96 for S. rugosoannulata. The Hg contents in the fruit bodies reflected the Hg contents in the substrate; the highest contents in the fruit bodies were found in P. cubensis (43.08±7.36ppm Hg) and P. stipticus (36.42±3.39ppm).

  18. PROCESSAMENTO E AVALIAÇÃO SENSORIAL DA CARNE DOS MOLUSCOS ESCARGOT (Achatina fulica) E ARUÁ (Pomacea lineata)

    OpenAIRE

    2009-01-01

    O presente trabalho foi desenvolvido com o objetivo de avaliar sensorialmente os produtos do processamento da carne dos moluscos escargot (Achatina fulica) e aruá (Pomacea lineata). Foram realizados dois processamentos em conserva (enlatado): triturada e defumada. Na avaliação sensorial da carne triturada observou-se diferença significativa entre os produtos, favorável ao escargot com valor médio de aceitação igual a 5,35 e 4,76 para o aruá. Para os produtos elaborado...

  19. The Novel Oomycide Oxathiapiprolin Inhibits All Stages in the Asexual Life Cycle of Pseudoperonospora cubensis - Causal Agent of Cucurbit Downy Mildew.

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    Yigal Cohen

    Full Text Available Oxathiapiprolin is a new oomycide (piperidinyl thiazole isoxazoline class discovered by DuPont which controls diseases caused by oomycete plant pathogens. It binds in the oxysterol-binding protein domain of Oomycetes. Growth chambers studies with detached leaves and potted plants showed remarkable activity of oxathiapiprolin against Pseudoperonospora cubensis in cucurbits. The compound affected all stages in the asexual life cycle of the pathogen. It inhibited zoospore release, cystospore germination, lesion formation, lesion expansion, sporangiophore development and sporangial production. When applied to the foliage as a preventive spray no lesions developed due to inhibition of zoospore release and cystospore germination, and when applied curatively, at one or two days after inoculation, small restricted lesions developed but no sporulation occurred. When applied later to mature lesions, sporulation was strongly inhibited. Oxathiapiprolin suppressed sporulation of P. cubensis in naturally-infected leaves. It exhibited trans-laminar activity, translocated acropetaly from older to younger leaves, and moved from the root system to the foliage. Seed coating was highly effective in protecting the developed cucumber plants against downy mildew. UV microscopy observations made with cucumber leaves infected with P. cubensis revealed that inhibition of mycelium growth and sporulation induced by oxathiapiprolin was associated with callose encasement of the haustoria.

  20. Identification of Genetic Variation between Obligate Plant Pathogens Pseudoperonospora cubensis and P. humuli Using RNA Sequencing and Genotyping-By-Sequencing.

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    Carly F Summers

    Full Text Available RNA sequencing (RNA-seq and genotyping-by-sequencing (GBS were used for single nucleotide polymorphism (SNP identification from two economically important obligate plant pathogens, Pseudoperonospora cubensis and P. humuli. Twenty isolates of P. cubensis and 19 isolates of P. humuli were genotyped using RNA-seq and GBS. Principle components analysis (PCA of each data set showed genetic separation between the two species. Additionally, results supported previous findings that P. cubensis isolates from squash are genetically distinct from cucumber and cantaloupe isolates. A PCA-based procedure was used to identify SNPs correlated with the separation of the two species, with 994 and 4,231 PCA-correlated SNPs found within the RNA-seq and GBS data, respectively. The corresponding unigenes (n = 800 containing these potential species-specific SNPs were then annotated and 135 putative pathogenicity genes, including 3 effectors, were identified. The characterization of genes containing SNPs differentiating these two closely related downy mildew species may contribute to the development of improved detection and diagnosis strategies and improve our understanding of host specificity pathways.

  1. Lymnaea Diaphana; a study of Topotypic specimens (Pulmonata: Lymnaeidae

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    W. Lobato Paraense

    1984-03-01

    Full Text Available A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.É apresentada uma descrição da espécie lymnaea diaphana king, 1830, baseada em material coletado na sua localidade-tipo, San Gregorio, na costa norte do Estreito de Magalhães, província chilena de

  2. Lymnaea rupestris sp. n. from Southern Brazil (Pulmonata: Lymnaeidae

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    W. Lobato Paraense

    1982-12-01

    Full Text Available A new species of South American lymnaeid snail, Lymnaea rupestris, is described. So far it has been found only in its type-locality, Nova TeuTõnia, a village in the municipality of Seara (27° 07' S, 52° 17' W, state of Santa Catarina, Brazil. It is distinguishable, by characteristics of the shell and internal organs, from the other two lymnaeid species known to occur in the area, Lymnaea columella and L. viatrix. Its shell has 4 markedly shouldered whorls, deep suture, ovoid or rounded aperture occupying about half the length of the shell, and reaches about 6 mm in length in adults; in columella and viatrix the shell has 4-5 rounded whorls, shallow suture, and reaches over 10 mm in adults; the aperture is ovoid, occupying about half the length of the shell in viatrix, about two thirds in columella. Anatomically it is readily separated from L. columella by the shape of the ureter, straight in rupestris, with a double flexure in columella. Comparison with L. viatrix shows the following main differences: distalmost portion of the oviduct with a low, caplike lateral swelling in rupestris, with a well-developed pouch in viatrix; uterus bent abruptly caudalward in rupestris, only slightly curved rightward in viatrix; basal half of the spermathecal duct hidden by the prostate in rupestris, wholly visible or nearly so in viatrix; spermiduct sinuous and uniformly wide in rupestris, straight and gradually narrowing in viatrix; prostate more than half as long and nearly as wide as the nidamental gland, and with a slit-like lumen in cross-section in rupestris, less than half as long as and much narrower than the nidamental gland, and with an inward fold in cross-section in viatrix; penial sheath about as long and as wide as the prepuce in rupesris, shorter and narrower than the prepuce in viatrix. An important ecological characteristic of L. rupestris is its habitat on wet rocks most often outside bodies of water, although in close proximity to them

  3. Susceptibility of two-week old Lymnaea natalensis to some plant extracts.

    Science.gov (United States)

    Kela, S L; Ogunsusi, R A; Ogbogu, V C; Nwude, N

    1989-01-01

    The molluscacidal potency of 17 Nigerian plants extracted by the unevaporated crude water (UECW) method was evaluated on two-week old Lymnaea natalensis Krauss. Five extracts were not active but extracts of Balanites aegytiaca, Blighia sapida, Boswellia dalzielii, Cissampelos mucronata, Detarium microcarpum, Kigelia africana, Opilia celtidifolia, Parkia clappertoniana, Polygonum limbatum, Pseudocedrela kotschyi, Nauclea latifolia and Securidaca longipedunculata were molluscacidal. There is potential for their future use in the integrated control of Lymnaea natalensis, as well as other snails. Mortality data for lethal concentration values for all extracts were analysed by use of probit transformation. The upper and lower fiducial limits of the LC50 (P = 0.05) were also determined.

  4. Effect of the exposure to Fasciola hepatica (Trematoda: Digenea) on life history traits of Lymnaea cousini and Lymnaea columella (Gastropoda: Lymnaeidae).

    Science.gov (United States)

    Salazar, Laura; Estrada, Victoria E; Velásquez, Luz E

    2006-10-01

    The snails Lymnaea columella and Lymnaea cousini have both been reported as intermediate hosts of Fasciola hepatica in Colombia. The effect of the exposure to the parasite on survival, fecundity and size of these snails was evaluated by means of experimental infections and the life history traits of control and exposed groups were compared. Infection rates were 82.2 and 34% for L. columella and L. cousini, respectively. A reduction in fitness was observed in both species when exposed to the parasite: fecundity alone was reduced in L. columella whereas in L. cousini there was also a decline in survival rate. Unlike other studies, increased size was not observed in either species. On the contrary, a reduction in growth rate was observed in L. columella.

  5. Resurrection of Scolopendra longipes Wood and Scolopendra cubensis Saussure from synonymy with Scolopendra alternans Leach (Chilopoda, Scolopendromorpha, Scolopendridae): an enigmatic species-group needing phylogeographic analysis, with an overview on the origin and distribution of centipedes in the Caribbean region.

    Science.gov (United States)

    Mercurio, Randy J

    2016-05-12

    Resurrection of Scolopendra longipes Wood, 1862, and Scolopendra cubensis Saussure, 1860, from junior synonymy with Scolopendra alternans Leach, 1815, is proposed. A neotype specimen of Scolopendra longipes is designated. Scolopendra longipes has a restricted range from the Dry Tortugas up through the Florida Keys of Monroe County into the mainland Florida counties of Collier and Dade southeast to the Bahamas, while Scolopendra cubensis is endemic to Cuba. Characters distinguishing S. longipes, and S. cubensis from S. alternans are illustrated and compared using digital photography, micrography and morphometric data. It is suggested that what has been considered Scolopendra alternans from southern Florida through the Caribbean and into northern South America is probably an evolving species-group that has undergone major diversification sometime during the Paleocene and early Eocene ~65.5-50 million years ago (Ma), mainly due to geographic isolation caused by a combination of plate tectonics and 100,000 year cycles of glaciation/deglaciation.

  6. Life-history traits of Fossaria cubensis (Gastropoda: Lymnaeidae under experimental exposure to Fasciola hepatica (Trematoda: Digenea

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    Gutiérrez Alfredo

    2000-01-01

    Full Text Available The effect of exposing the lymnaeid snail Fossaria cubensis to the trematode Fasciola hepatica on the snail population's life-history traits was studied under laboratory conditions. Exposed individuals showed a lower survival rate than control snails, although from week 7 onward a slower decrease of this parameter in relation to the control group was observed. There were higher values of fecundity rate for the controls compared to the exposed group except during weeks 9, 10, 11 and 12, which was the time that followed the period when almost all of the infected snails died. Both the intrinsic and finite rates of natural increase were significantly higher for the control group, but exposed snails still attained a lower mean generation time. Age-specific trade-offs were found, mainly for the weekly increase in size versus the number of eggs per mass, the weekly increase in size versus the number of viable eggs per mass, the number of masses versus the hatching probability and the number of eggs versus the hatching probability. All these negative associations were significant for juveniles of both control and exposed snails and not for adults; however, exposed young individuals exhibited much higher values of the correlation coefficient than control animals.

  7. Venomous mollusks: the risks of human accidents by conus snails (gastropoda: conidae in Brazil Moluscos peçonhentos: riscos de acidentes em humanos pelo molusco Conus (Gastrópode: cunidae in Brazil

    Directory of Open Access Journals (Sweden)

    Vidal Haddad Junior

    2006-10-01

    Full Text Available Mollusks of the genus Conus present a venomous apparatus composed of radulae, a chitin structure linked to glands, which injects potent neurotoxic peptides, causing serious human envenomation and even death, associated with the blockage of certain receptors and muscular paralysis. No reported envenomation has occurred in Brazil, but certain populations are at risk of accidents.Os moluscos do gênero Conus apresentam um aparato venenoso composto de uma rádula quitinosa ligada a glândulas de peçonha, causando envenenamentos humanos graves e mesmo óbitos pela ação neurotóxica indutora do bloqueio de vários receptores e paralisia muscular. Não há casos descritos de envenenamento no país, mas determinadas populações correm risco de acidentes.

  8. Metabolic acceleration in the pond snail Lymnaea stagnalis?

    Science.gov (United States)

    Zimmer, Elke I.; Ducrot, V.; Jager, T.; Koene, J.; Lagadic, L.; Kooijman, S. A. L. M.

    2014-11-01

    Under constant environmental conditions, most animals tend to grow following the von Bertalanffy growth curve. Deviations from this curve can point to changes in the environment that the animals experience, such as food limitation when the available food is not sufficient or suitable. However, such deviations can also point to a phenomenon called metabolic acceleration, which is receiving increasing attention in the field of Dynamic Energy Budget (DEB) modeling. Reasons for such an acceleration are usually changes in shape during ontogeny, which cause changes in the surface area to volume ratio of the organism. Those changes, in turn, lead to changes in some of the model parameters that have length in their dimension. The life-history consequences of metabolic acceleration as implemented in the DEB theory are an s-shaped growth curve (when body size is expressed as a length measure) and a prolongation of the hatching time. The great pond snail Lymnaea stagnalis was earlier found to be food limited during the juvenile phase in laboratory experiments conducted under classical ecotoxicity test protocols. The pond snail has isomorphic shell growth but yet does not exhibit the expected von Bertalanffy growth curve under food limitation. When applying the standard DEB model to data from such life-cycle experiments, we also found that the hatching time is consistently underestimated, which could be a sign of metabolic acceleration. We here present an application of the DEB model including metabolic acceleration to the great pond snail. We account for the simultaneous hermaphroditism of the snail by including a model extension that describes the relative investment into the male and female function. This model allowed us to adequately predict the life history of the snail over the entire life cycle. However, the pond snail does not change in shape substantially after birth, so the original explanation for the metabolic acceleration does not hold. Since the change in shape

  9. Development of Ca2+ hotspots between Lymnaea neurons during synaptogenesis.

    Science.gov (United States)

    Feng, Zhong-Ping; Grigoriev, Nikita; Munno, David; Lukowiak, Ken; MacVicar, Brian A; Goldberg, Jeffrey I; Syed, Naweed I

    2002-02-15

    Calcium (Ca2+) channel clustering at specific presynaptic sites is a hallmark of mature synapses. However, the spatial distribution patterns of Ca2+ channels at newly formed synapses have not yet been demonstrated. Similarly, it is unclear whether Ca2+ 'hotspots' often observed at the presynaptic sites are indeed target cell contact specific and represent a specialized mechanism by which Ca2+ channels are targeted to select synaptic sites. Utilizing both soma-soma paired (synapsed) and single neurons from the mollusk Lymnaea, we have tested the hypothesis that differential gradients of voltage-dependent Ca2+ signals develop in presynaptic neuron at its contact point with the postsynaptic neuron; and that these Ca2+ hotspots are target cell contact specific. Fura-2 imaging, or two-photon laser scanning microscopy of Calcium Green, was coupled with electrophysiological techniques to demonstrate that voltage-induced Ca2+ gradients (hotspots) develop in the presynaptic cell at its contact point with the postsynaptic neuron, but not in unpaired single cells. The incidence of Ca2+ hotspots coincided with the appearance of synaptic transmission between the paired cells, and these gradients were target cell contact specific. In contrast, the voltage-induced Ca2+ signal in unpaired neurons was uniformly distributed throughout the somata; a similar pattern of Ca2+ gradient was observed in the presynaptic neuron when it was soma-soma paired with a non-synaptic partner cell. Moreover, voltage clamp recording techniques, in conjunction with a fast, optical differential perfusion system, were used to demonstrate that the total whole-cell Ca2+ (or Ba2+) current density in single and paired cells was not significantly different. However, the amplitude of Ba2+ current was significantly higher in the presynaptic cell at its contact side with the postsynaptic neurons, compared with non-contacted regions. In summary, this study demonstrates that voltage-induced Ca2+ hotspots develop

  10. Padrões dermatoscópicos do molusco contagioso: estudo de 211 lesões confirmadas por exame histopatológico

    OpenAIRE

    Ianhez, Mayra; Silmara da Costa P Cestari; Enokihara, Mauro Yoshiaki; Seize,Maria Bandeira de Paiva Melo

    2011-01-01

    FUNDAMENTOS: Embora de fácil diagnóstico, o molusco contagioso pode apresentar-se como lesões inflamadas, únicas ou pequenas de difícil diagnóstico. OBJETIVO: Descrever características dermatoscópicas do molusco contagioso e comparar achados do exame clínico e dermatoscópico. MÉTODOS: Avaliou-se clínica e dermatoscopicamente lesões confirmadas pela histopatologia em 57 pacientes. RESULTADOS: Nos exames clínico e dermatoscópico de 211 lesões, foram visualizados orifícios em 50,24% e 96,68% das...

  11. Estudos higiênicos sôbre os crustáceos e moluscos da Baía de Guanabara (Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Lejeune Pacheco Henriques de Oliveira

    1944-04-01

    Full Text Available Revisão da literatura médica sôbre higiene de crustáceos e moluscos marinhos. Intoxicações por elementos extranhos às carnes de crustáceos e moluscos: por sais de cobre, vegetais tóxicos; estranho e chumbo nas conservas de crustáceos; botulismo. Putrefação de ostras e doenças de ostras provocadas por cogumelos; crustáceos e moluscos guardados em geladeiras bolorentas. Lista das espécies de moluscos comestíveis da Bahia de Guanabara. Lista das espécies de crustáceos comestíveis da Bahia de Guanabara. Veiculação de micro-organismos patogênicos ao homem por intermédio das carnes de crustáceos e de moluscos: veiculação do vibrião colérico, dos bacilos tíficos e paratíficos e de germes do grupo coli e do gênero Proteus. Vitalidade dos bacilos tíficos nas ostras. Listas dos moluscos veiculadores dos agentes causadores das febres tíficas e paratíficas. Conceitos antigos e modernos sõbre intoxicações por crustáceos; partidas de crustáceos salubres ou não conforme o local de venda. Estudos experimentais sôbre a "talassina" princípio tóxico existente em alguns crustáceos. "Mitilotoxina", intoxicações por mexilhões e outros acidentes incriminados aos moluscos. Enterotoxina estavfilocócica em ostras. Métodos de determinação da salubridade dos moluscos; verificações nas ostras brasileiras. Depuração dos crustáceos pelas soluções cloradas. Estabulação de caranguejos denominados vulgarmente de "guaiamus" e "ussás".Recording main medical publication on Hygiene of Mollusca and Crustacea. Food-poisoning. Decomposing oysters, and shell-fish sickness by fungi. Catalogue of eatable Crustacea and Mollusca of Rio de Janeiro. Significance of Mollusca and Crustacea in the spread of diseases. Longevity of Vibrio comma, Eberthella typhosa, Salmonella schottmuelleri, Salmonella paratiphi. Escherichia coli in oysters, Microorganisms in marked oysters. Comparison old written papers with moderns publications on food

  12. Potential of Hemianax ephippiger (Odonata-Aeshnidae) nymph as predator of Fasciola intermediate host, Lymnaea natalensis

    Institute of Scientific and Technical Information of China (English)

    Aly; Younes; Hanaa; El-Sherif; Fathia; Gawish; Marwa; Mahmoud

    2015-01-01

    Objective: To evaluate the predatory capacity of the Odonata, Hemianax ephippiger nymph as a biocontrol agent for the freshwater snail Lymnaea natalensis, intermediate host of Fasciola gigantica. Methods: Observations on the searching, attacking and devouring of the snails with a series of laboratory-based predation experiments, whose aims were to determine daily predation rate, differential predation on small-, medium- and large-sized snails were carried out. Results: Laboratory evaluation revealed that, the Odonata nymph could kill and consume all three sizes of snails. Searching and handling time of the predator differed depending on snail size and predator vulnerability. The predation rate varied also with respect to snail size and density.Conclusions: Our observations suggested that the predator Hemianax ephippiger may be a suitable bio-control agent of Lymnaea natalensis snail population.

  13. Behavioural responses of the snail Lymnaea acuminata to carbohydrates in snail-attractant pellets

    Science.gov (United States)

    Tiwari, Farindra; Singh, D. K.

    Snail control is one of the most important tools in the campaign to reduce the incidence of fascioliasis. In order to attain this objective, the method of bait formulation in order to contain an attractant and a molluscicide is an expedient approach to lure the target snail population to the molluscicide. This study identifies certain carbohydrates, namely sucrose, maltose, glucose, fructose and starch, for preparing such baits. These were tested on Lymnaea acuminata, an intermediate host of the digenean trematodes Fasciola hepatica and Fasciola gigantica. The behavioural responses of snails to these carbohydrates were examined. Significant variations in behavioural responses were observed in the snail even when the five carbohydrates were used in low concentrations in snail-attractant pellets. Starch emerged as the strongest attractant for Lymnaea acuminata, followed by maltose.

  14. Lymnaea stagnalis Snails Infection in Trematoda Larval of Shahrekord City Springs

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    Shahla Rivaz

    2014-03-01

    Full Text Available Abstract Background and objective: This study was established to determine the lymnaea stagnalis snails’ infection with trematodes larval stage in one of the springs of the Shahrekord city in Chahar Mahal and Bakhtiari. Materials and methods: To determine the snail infection to trematodes larval stages, the snails were caught from the field, and transferred to the Parasitology department of Razi Vaccine and Serum research Institute. Then stimulating of snails by light, tubing and squashing of them were used to detection and identification of the isolated cercariae. Results: Of 400 collected Snails from the referred springs, 320 of them identified as lymnaea stagnalis. Observed cercariae were identified and classificated as order Plagiorchis, family plagiorchiidae and genus opisthioglyphe and plagiorchis. In Chahar Mahal and Bakhtiari province due to having more than 10% of water content of country, ecological conditions can play important role to developing sensitive snail especially Lymnaeidae and be considered as a critical and suitable habitat for them.

  15. Behavior in Mus musculus of Schistosoma mansoni from mollusks treated with hydrocortisone Comportamento em Mus musculus do Schistosoma mansoni oriundo de moluscos tratados com hidrocortisona

    Directory of Open Access Journals (Sweden)

    Deborah Regina Serrano

    2005-10-01

    Full Text Available Twenty mice were exposed to cercariae from mollusks treated with hydrocortisone and another 20 mice received cercariae from non-treated mollusks. The behavior of the parasites from the two groups of mollusks was compared based on the ability of cercariae to penetrate mice, on the total number of worms recovered after eight weeks of infection, on the relationship between the number of penetrating cercariae and the number of recovered worms and on the number of eggs in the feces. Treating the mollusks with hydrocortisone did not alter the ability of cercariae to penetrate mice nor did it affect the total number of worms recovered. The number of female worms, the number of coupled worms and the number of eggs in the feces were greater in mice infected by cercariae from mollusks treated with hydrocortisone.Vinte camundongos foram expostos a cercárias oriundas de moluscos tratados com hidrocortisona e outros vinte receberam cercárias de moluscos não tratados. O comportamento dos parasitas dos dois grupos foi comparado com base na habilidade das cercárias em penetrar nos camundongos, no número total de vermes recuperados, após oito semanas de infecção, na relação entre o número de cercárias penetrantes e o número de vermes recuperados e o número de ovos nas fezes. O tratamento dos moluscos com hidrocortisona não alterou a habilidade das cercárias em penetrar nos camundongos nem afetou o número total de vermes recuperados. O número de vermes fêmeas, o número de vermes acasalados e o número de ovos nas fezes aumentaram em camundongos infectados por cercárias de moluscos tratados com hidrocortisona.

  16. Limnaea peregrina Clessin, 1882, Synonym of Lymnaea columella Say, 1817 (Gastropoda: Lymnaeidae

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    W Lobato Paraense

    1994-12-01

    Full Text Available A description is given of the shell, radula, renal region, reproductive system and egg capsules of topotypic specimens of limnaea peregrina Clessin, 1882. This investigation intends contributing to define the specific identity of that nominal species. A close anatomical comparison with Lymnaea columella Say, 1817 from Michigan, USA, shows that both forms are indistinguishable, giving support to previous inferences from some authors. Data on egg hatching are presented.

  17. The freshwater snail lymnaea rubiginosa as an experimental host of Angiostrongylus malaysiensis: a preliminary report.

    Science.gov (United States)

    Dondero, T J; Lim, B L

    1976-03-01

    Preliminary studies have shown that Lymnaea rubiginosa, a common fresh-water snail in Peninsular Malaysia, which is easily colonized and reared in the laboratory, is a capable experimental intermediate host for Angiostrongylus malaysiensis. Overall 73% of the snails tested became infected following 6 hours exposure to infective rat faeces. Higher infection rates, up to 100%, and heavier worm loads, occurred among the larger sized snails. Snail attrition was low except when very heavy worm loads were acquired.

  18. 45Ca uptake from water by snails (Lymnaea vulgaris) in control and detergent-polluted samples.

    Science.gov (United States)

    Misra, V; Lal, H; Viswanathan, P N; Murti, C R

    1984-02-01

    A biostatic assay method involving 45Ca uptake into shells and tissues of snails (Lymnaea vulgaris) in 72 hr was developed to follow the effect of detergent-polluted water on ecosystems. There was a marked decrease in the 45Ca uptake by shells and tissues of linear alkyl benzene sulfonate-exposed animals as compared to controls. No change in 45Ca uptake was observed in dead shells, thereby excluding the possibility of passive exchange.

  19. Identificación de Yarrowia lipolytica (Ascomycota: Hemiascomycetes como contaminante en la obtención de amplificados del gen 28S rRNA de moluscos

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    Jenny Chirinos

    2011-05-01

    Full Text Available En el presente trabajo se identifica una secuencia de DNA no esperada proveniente de los amplificados del gen 28S rRNA de moluscos terrestres. Las extracciones de DNA se realizaron del tejido del pie de caracoles terrestres por el método del CTAB modificado. Las PCRs fueron llevadas a cabo con primers universales para el gen COI e iniciadores diseñados para moluscos, para el marcador 16S rRNA, 28S rRNA y la región ITS-2. Los tamaños aproximados de las bandas de los amplificados de moluscos fueron de 706 pb para el COI, 330 pb para el 16S rRNA, 900 pb para el ITS-2 y 583 pb para el 28S rRNA; un amplificado del último marcador fue de una longitud inesperada, ~340 pb. Las secuencias de DNA fueron comparadas con la base de datos del GenBank mediante el programa BLASTn y la muestra con la banda de tamaño inesperado resultó en un 100% de identidad y cobertura del 99% con el gen 26S rRNA de la levadura Yarrowia lipolytica. El análisis filogenético con Neighbour-Joining y los valores de divergencia confirmaron la identificación, proporcionando resultados que apoyan la ubicación taxonómica de la especie dentro del clado de los Hemiascomycetes.

  20. Prevalence of Fasciola in cattle and of its intermediate host Lymnaea snails in central Vietnam.

    Science.gov (United States)

    Nguyen, Sam Thi; Nguyen, Duc Tan; Van Nguyen, Thoai; Huynh, Vu Vy; Le, Duc Quyet; Fukuda, Yasuhiro; Nakai, Yutaka

    2012-12-01

    The aims of this study were to investigate the prevalence of natural Fasciola infections in both the definitive hosts (cattle) and the intermediate hosts (Lymnaea snails) in central Vietnam. A total of 1,075 fecal samples, randomly collected from cattle in Binh Dinh, Khanh Hoa, and Phu Yen provinces, were examined for Fasciola eggs by a sedimentation method. The overall prevalence of Fasciola was 45.3 %. A subset of the animals (235) was also screened for antibodies against Fasciola by an enzyme-linked immunosorbent assay. Overall, 46.3 % of these animals were shedding Fasciola eggs while 87.2 % were Fasciola seropositive. A lower prevalence of Fasciola was observed in calves ≤ 2 years of age (37.6 %) compared to that in cattle >2 years of age (53.7 %) (p Lymnaea viridis and 1.128 Lymnaea swinhoei examined, 31 (0.95 %) and seven (0.62 %), respectively, were found to be infected with Fasciola. This appears to be the first epidemiological survey of the prevalence of Fasciola in cattle and snails in these three provinces in central Vietnam.

  1. Los moluscos y la contaminación: Una revisión Mollusks and pollution: A review

    Directory of Open Access Journals (Sweden)

    Erick Raúl Baqueiro-Cárdenas

    2007-10-01

    Full Text Available Los moluscos son un grupo megadiverso que en cuanto a número de especies sólo lo sobrepasan los insectos y los nemátodos; no así en cuanto a la diversidad de hábitos de vida y hábitats que ocupan. Las especies de moluscos se encuentran en los desiertos y en las zonas polares; en los trópicos y en las grandes profundidades oceánicas. Sin embargo, es en las lagunas litorales tropicales donde alcanzan su máxima diversidad y función; los hay desde consumidores primarios en las redes tróficas, tanto de herbívoros como de detritívoros, hasta depredadores de segundo nivel y parásitos especializados. Existen especies especializadas y especies oportunistas, lo que se manifiesta en diferentes respuestas a las modificaciones del hábitat y la contaminación. En esta contribución se analizan las respuestas que individuos o poblaciones de moluscos tienen al impacto de la contaminación, así como sus mecanismos etológicos y fisiológicos de adaptación o sobrevivencia. Tomando en consideración lo anterior, se plantea su aplicación como indicadores de contaminación, ya sea por la desaparición de especies estenobiónticas, el predominio de las euribiónticas o por su capacidad de acumular contaminantes cuando sus concentraciones no alcanzan dosis que impacten las poblaciones, bien en procesos de bioacumulación a lo largo del ciclo de vida del organismo o por biomagnificación a través de las cadenas tróficas o de los cambios fisiológicos producidos por la contaminación.Mollusks are a mega-diverse group, surpassed only by insects and nematodes in number of species, but not in diversity of life strategies and occupied habitats; they can be found from deserts to polar zones and from the highest mountain to the deepest ocean trench. But it is at tropical coastal lagoons where they find their maximum diversity and function; there are first order consumers in both herbivore and detritus food chains, to second order carnivores and specialized

  2. Metabolitos secundarios, letalidad y actividad antimicrobiana de los extractos de tres corales y tres moluscos marinos de Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    Gabriel Ordaz

    2010-06-01

    Full Text Available A los extractos crudos de los octocorales Eunicea sp., Muricea sp. y Pseudopterogorgia acerosa y de los moluscos Pteria colymbus, Phylonotus pomum y Chicoreus brevifrons, se les realizaron pruebas químicas, las cuales evidenciaron en todos ellos, la presencia de metabolitos secundarios como alcaloides, esteroles insaturados y triterpenos pentacíclicos. Sólo se detectaron sesquiterpenlactonas, saponinas, taninos, glicósidos cianogénicos y glicósidos cardiotónicos en algunos de los extractos de los octocorales, lo cual sugiere que la biosíntesis de estos metabolitos es propia de este grupo de organismos. Asimismo, se evaluó la actividad letal y antimicrobiana de los extractos de los octocorales y moluscos. En el bioensayo de letalidad, todos los extractos resultaron letales frente al crustáceo Artemia salina (CL50Secondary metabolites, lethality and antimicrobial activity of extracts from three corals and three marine mollusks from Sucre, Venezuela. The study of biochemical activity of extracts obtained from marine organisms is gaining interest as some have proved to have efficient health or industrial applications. To evaluate lethality and antimicrobial activities, some chemical tests were performed on crude extracts of the octocorals Eunicea sp., Muricea sp. and Pseudopterogorgia acerosa and the mollusks Pteria colymbus, Phyllonotus pomum and Chicoreus brevifrons, collected in Venezuelan waters. The presence of secondary metabolites like alkaloids, unsaturated sterols and pentacyclic triterpenes in all invertebrates, was evidenced. Additionally, sesquiterpenlactones, saponins, tannins, cyanogenic and cardiotonic glycosides were also detected in some octocoral extracts, suggesting that biosynthesis of these metabolites is typical in this group. From the lethality bioassays, all extracts resulted lethal to Artemia salina (LC50<1.000μg/ml with an increased of lethal activity with exposition time. P. pomum extract showed the highest

  3. Effects of Developmental Temperature on Gametocysts and Oocysts of Two Species of Gregarines Blabericola migrator and Blabericola cubensis (Apicomplexa: Eugregarinida: Blabericolidae) Parasitizing Blaberid Cockroaches (Dictyoptera: Blaberidae).

    Science.gov (United States)

    Kolman, Jon A; Clopton, Richard E; Clopton, Debra T

    2015-12-01

    Abiotic environmental conditions, especially temperature and humidity, have profound effects on the growth and development of gregarines, but these effects remain largely undocumented. Quantifying the effects of environmental conditions on the growth and development of exogenous gregarine ontogenetic stages is an important first step in understanding the transmission, population dynamics, and environmental persistence of gregarine infection. In this study, we examined the effect of 6 environmental temperatures (10, 18, 22, 27, 35, and 40 C) at constant humidity (0 mmHg vapor pressure deficit) on gametocyst development and oocyst viability in 2 gregarine species: Blabericola migrator and Blabericola cubensis parasitizing the Tiger-striped Hissing Cockroach, Princisia vanwaerebecki, and the Discoid Cockroach, Blaberus discoidalis, respectively. Temperature has a significant effect on gametocyst development and oocyst viability for both gregarine species. Gametocyst development for both gregarine species displays a similar threshold response to environmental temperature: 10 and 40 C represent extremes outside their developmental range, but within these extremes, the relationship between gametocyst development and temperature is weakly direct. Dehiscence increased with temperature from 68% at 18 C to 93% at 22 C and remained at that level through 35 C. Developmental temperature also has a meaningful but inverse effect on oocyst viability of both B. migrator and B. cubensis. For both species, oocyst viability is highest at 18 and 22 C and is significantly reduced at 27 and 35 C. Thus oocyst production and sporozoite viability are linked but environmentally independent phenomena. Overall, there is an acceptable developmental temperature zone for B. migrator and B. cubensis that ranges from 18 to 27 C, but production of viable sporozoites is greatest in a relatively narrow zone around 22 C. Prior studies have postulated that mechanisms that concentrate oocysts and hosts

  4. Enzyme Inhibition by Molluscicidal Components of Myristica fragrans Houtt. in the Nervous Tissue of Snail Lymnaea acuminata

    Directory of Open Access Journals (Sweden)

    Preetee Jaiswal

    2010-01-01

    Full Text Available This study was designed to investigate the effects of molluscicidal components of Myristica fragrans Houtt. (Myristicaceae on certain enzymes in the nervous tissue of freshwater snail Lymnaea acuminata Lamarck (Lymnaeidae. In vivo and in vitro treatments of trimyristin and myristicin (active molluscicidal components of Myristica fragrans Houtt. significantly inhibited the acetylcholinesterase (AChE, acid and alkaline phosphatase (ACP/ALP activities in the nervous tissue of Lymnaea acuminata. The inhibition kinetics of these enzymes indicates that both the trimyristin and myristicin caused competitive noncompetitive inhibition of AChE. Trimyristin caused uncompetitive and competitive/noncompetitive inhibitions of ACP and ALP, respectively whereas the myristicin caused competitive and uncompetitive inhibition of ACP and ALP, respectively. Thus results from the present study suggest that inhibition of AChE, ACP, and ALP by trimyristin and myristicin in the snail Lymnaea acuminata may be the cause of the molluscicidal activity of Myristica fragrans.

  5. Ambang waktu pendedahan telur Lymnaea sp untuk mengamati abnormalitas embrio sebagai parameter dalam uji hayati terhadap karbamat

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    Hari Soepriandono

    2000-12-01

    Full Text Available The aim of this study was to know the specific expose period of the Lymnaea sp.'s embyos and their age in order to utilization eggs of Lymnaea sp. in bioassay. Fifty individuals of Lymnaea sp. collected from Gonggan River Magetan were captured in laboratory. Egg cluster of each individual then was placed in petry dish which was filled by Baycarb 500 EC of 0.0001, 0.001 and 0.01 ppm. The result showed that 12 hours exposure in Baycarb 500 EC was the effective time since within 6 hours all of embryos were death and abnormalities of the survivals was detected in the embryos of 48 and 72 hours.

  6. Nuevos registros de moluscos carboníferos en la sierra del Tontal, Precordillera de San Juan

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    R.R. Lech

    2006-03-01

    Full Text Available Se da a conocer una asociación de moluscos fósiles, Peruvispira aff. 'P'. sueroi, Nuculopsis? sp. y Limipecten sp., hallada en la Formación Ciénaga Larga del Tontal. Esta formación aflora en el faldeo occidental de la sierra del Tontal, al este de la región de Rincón Blanco, Precordillera de San Juan. Las dos primeras especies se encuentran en la zona fosilífera 1, junto a Aseptella? sp. y Productella sp., en tanto que Limpecten sp. se presenta en la zona fosilífera 4 junto a gasterópodos y bivalvos indeterminados. Considerando la asociación de braquiópodos fósiles y el contenido de palinomorfos presentes en la Formación Ciénaga Larga del Tontal se estima que su edad estaría comprendida entre lo más tardío del Carbonífero Temprano y el Carbonífero Tardío.

  7. Identificación fitoquímica de las hojas y ramas de la Helietta cubensis Monach-Moldenke, especie endémica de Cuba

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    Sandra del Castillo Ochoa

    2004-04-01

    Full Text Available Se describe el tamizaje fitoquímico preliminar de las hojas y ramas de la Helietta cubensis Monach -Moldenke, especie endémica cubana que crece en la cima de los mogotes de Pinar del Río. La detección de los metabolitos secundarios se realizó mediante reactivos de identificación específicos para cada familia de compuestos. En ambas partes de la especie se identificaron en alta abundancia flavonoides y lactonas/coumarinas; en baja concentración se detectaron triterpenos/esteroides, lípidos/aceites esenciales, saponinas y carotenos y no la presencia de aminas y alcaloides. Mediante el análisis por cromatografía de capa fina se pudo corroborar los resultados obtenidos en la identificación de alcaloides, flavonoides y coumarinas. En general, los resultados obtenidos fueron homogéneos para ambas partes de la planta, y constituyen el primer reporte de la composición química para esta especie.The preliminary phytochemical screening of the leaves and branches of Helietta cubensis Monach-Moldenke, a Cuban endemic species that grows in the hummocks of Pinar del Río is described. The detection of the secondary metabolites was carried out by reagents of identification that are specific for each family of compounds. A great number of flavonoids and lactones/coumarines was identified in both parts of the species. A low concentration of triterpenes/steroids, lipids/essential oils, saponins and carotenes was observed, whereas amines and alkaloids were not detected. The results obtained in the identification of alkaloids, flavonoids and coumarines were corroborated by thin layer chromatography. In general, the results attained were homogeneous for both parts of the plant and they are the first report about the chemical composition of this species.

  8. A Lymnaea stagnalis Embryo Test for Toxicity Bioindication of Acidification and Ammonia Pollution in Water

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    Robert Mazur

    2016-07-01

    Full Text Available The paper presents a study leading to a new acute toxicity test on embryonic and juvenile organisms of the great pond snail (Lymnaea stagnalis Linnaeus. Sulfuric acid, nitric acid, and ammonium hydroxide were used as waterborne toxicants in laboratory experiments. The exposure time was 24 h. Tests were conducted in 5–10 replications for each toxicant. The toxicity of the substances was classified according to different scales and the test’s sensitivity was compared to that of the commonly used bioindicator Daphnia magna Straus. The assessment of toxicity impact was supported by microscopic observations. The probit method was used as a parametric statistical procedure to estimate LC50 and the associated 95% confidence interval. Our study showed that the early developmental stages of Lymnaea stagnalis are very sensitive bioindicators, making it possible to detect even very low levels of the above-mentioned water toxicants. The highest toxicity is shown by ammonium hydroxide with LC50/24h values, respectively, 24.27 for embryos and 24.72 for juvenile forms, and the lowest is shown by nitric acid ions with LC50/24h values, respectively, 105.19 for embryos and 170.47 for juvenile forms. It is highly cost-effective due to simple and efficient breeding and the small size of the organisms in the bioassay population. Compared with Daphnia magna, relatively low concentrations of toxicants caused a lethal effect on embryonic and juvenile organisms of the great pond snail. Owing to their common occurrence and sensitivity, early developmental forms of Lymnaea stagnalis can be a valuable new tool in biomonitoring of the freshwater environment.

  9. Oxidative stress and genotoxic effect of zinc oxide nanoparticles in freshwater snail Lymnaea luteola L.

    Science.gov (United States)

    Ali, Daoud; Alarifi, Saud; Kumar, Sudhir; Ahamed, Maqusood; Siddiqui, Maqsood A

    2012-11-15

    Understanding the toxic effects of nanoparticles on aquatic organism is the biggest obstacle to the safe development of nanotechnology. However, little is known about the toxic mechanisms of zinc oxide nanoparticles (ZnONPs) in freshwater snail Lymnaea luteola (L. luteola). This study was designed to investigate the possible mechanisms of genotoxicity induced by ZnONPs in freshwater snail L. luteola. ZnONPs (32 μg/ml) elicited a significant (psnail L. luteola may be used as suitable test model for nanoecotoxicological studies in future.

  10. An octopaminergic system in the CNS of the snails, Lymnaea stagnalis and Helix pomatia

    OpenAIRE

    1998-01-01

    Octopamine (OA) levels in each ganglion of the terrestrial snail, Helix pomatia, and the pond snail, Lymnaea stagnalis, were measured by using the HPLC technique. In both species an inhomogeneous distribution of OA was found in the central nervous system. The buccal ganglia contained a concentration of OA (12.6 pmol mg-1 and 18.8 pmol mg-1) that was two to three times higher than the pedal (4.93 pmol mg-1 and 9.2 pmol mg-1) or cerebral (4.46 pmol mg-1 and 4.9 pmol mg-1) ganglia of Helix and L...

  11. TAXOCENOSIS DE MOLUSCOS Y CRUSTÁCEOS EN RAÍCES DE Rhizophora mangle (RHIZOPHORACEAE EN LA BAHÍA DE CISPATÁ, CÓRDOBA, COLOMBIA

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    JORGE ALEXANDER QUIRÓS R

    2013-01-01

    Full Text Available A pesar del conocimiento existente sobre la ecología de los manglares en la bahía de Cispatá, pocos estudios han sido enfocados en la asociación de invertebrados en las raíces del mangle rojo, por lo que entre diciembre 2010 y septiembre 2011, se caracterizó la taxocenosis de moluscos y crustáceos en raíces de Rhizophora mangle en dos sectores de muestreo de la bahía de Cispatá, Colombia. Para la recolección del material biológico se tomaron al azar tres raíces de mangle rojo con un diámetro homogéneo por estación. Los moluscos y crustáceos fueron obtenidos de la raíz raspando la superficie con un cuchillo, luego fueron separados y fijados en formalina al 10 % para su posterior identificación hasta especie mediante claves taxonómicas especializadas. De los 12289 individuos recolectados en los cuatro muestreos, 10470 pertenecieron al phylum Mollusca (85,2 % y los restantes 1819 al subphylum Crustacea (14,8 %. De moluscos se identificaron 14 especies distribuidas en 11 familias y dos clases; Bivalvia y Gastropoda. De crustáceos se identificaron 24 especies distribuidas en 16 familias y cuatro órdenes; Sessillia, Decapoda, Isopoda y Amphipoda. En los dos sectores de muestreo Mytella charruana, Balanus eburneus y Crassostrea rhizophorae fueron las especies más importantes en términos de abundancia, no obstante se sabe que moluscos como M. charruana y B. eburneus presentan una gran capacidad de adaptación y ajuste a las variaciones hidroclimáticas, lo que se reflejó en la do- minancia de dichas especies en el sector con mayor influencia del río Sinú. La presencia de los crustáceos Petrolisthes armatus y Aratus pisonii en el sector con más cercanía al mar Caribe, indica que son especies de bosques de manglar con gran movilidad y mecanismos de adaptación fisiológicos.

  12. Estudio bacteriológico de bivalvos del Golfo de Nicoya, Costa Rica II. Condición del molusco al momento de comerlo

    OpenAIRE

    Fernández, Bernal; Ryan, Kathleen A.

    2016-01-01

    Para un estudio de la calidad sanitaria de moluscos al momento de comerlos, escogimos nueve tabernas de la Ciudad de San J osé dentro de aquellas que usualmente tenían a la venta "cocteles de chuchecas" (en realidad, de pianguas), de suerte que representaran tres niveles socio-económicos-sanitarios. De ellas adquirimos un total de 66 muestras de cocteles para su examen bacteriológico por coliformes totales y fecales, Staphylococcus aureusy salmonelas.Solamente un 7% de las muestras resultaron...

  13. Guía básica para el cultivo de moluscos bivalvos del Pacífico Panameño: conchuela, ostras y concha negra.

    OpenAIRE

    Guerra-Lima, Z.I.,; Vergara-López, Pablo

    2012-01-01

    La Autoridad de los Recursos Acuáticos de Panamá, a través del Proyecto de Fortalecimiento Institucional e Integración de Políticas y Estrategias para el Desarrollo Rural Nacional, financiado por el Ministerio de Economía finanzas y la Agencia Española de Cooperación Internacional para el Desarrollo, se complace en presentar esta guía sobre el cultivo de moluscos como una alternativa para la producción de alimentos, generación de empleos, divisas y para el repoblamiento con fines de recuperac...

  14. Estructura de la comunidad de moluscos y relaciones tróficas en el litoral rocoso del estado Sucre, Venezuela

    Directory of Open Access Journals (Sweden)

    Johanna Fernández

    2006-12-01

    Full Text Available Se analizó la estructura de la comunidad de moluscos y sus relaciones tróficas en seis localidades del litoral rocoso con diferentes grados de exposición al oleaje (área expuesta y área protegida, en el Estado Sucre, Venezuela. El muestreo se llevó a cabo durante el período de marzo 2003 a febrero 2004. La recolección del material biológico se realizó de forma manual con ayuda de una espátula, dentro de una cuadrícula de 0.25 m², estableciéndose tres zonas: supra, medio e infralitoral. Los organismos fueron preservados en frascos con formalina al 10% para su posterior análisis. En el laboratorio fueron identificados, contados, y pesados en una balanza de 0.001g de precisión. Se determinó la abundancia total de especies, biomasa, constancia específica y por medio de una revisión bibliográfica se le asignó a cada especie su categoría trófica, clasificándolos en: herbívoros, filtradores, carnívoros y herbívoros -filtradores. Se obtuvo un total de 14 581 individuos (6 397.945 g representado por 68 especies correspondientes a las clases Gastropoda (39, Bivalvia (23 y Polyplacophora (6; contenidas en nueve órdenes y 31 familias. Los herbívoros fueron el grupo dominante (49%, seguido por filtradores (37%, carnívoros (13 % y herbívoros-filtradores (1%. Las especies herbívoras y herbívoras-filtradoras dominaron en el área protegida, mientras que en el área expuesta, fueron las carnívoras y filtradoras. Las especies constantes en las seis localidades durante el período de estudio fueron Planaxis nucleus, Mitrella ocellata, M. nycteis, Littorina interrupta, Tegula fasciata, Acmaea leucopleura, Ostrea equestris y Chiton squamosus. La distribución de los moluscos y los diferentes grupos tróficos, pueden estar controlados por adaptaciones morfológicas, así como el nivel de exposición al oleaje y composición del sustrato.Mollusc community structure and trophic relations in the rochy littoral zone in Sucre State

  15. Food intake, growth, and reproduction as affected by day length and food availability in the pond snail Lymnaea stagnalis

    NARCIS (Netherlands)

    Maat, ter A.; Zonneveld, C.; Visser, de J.A.G.M.; Jansen, R.F.; Montagne-Wajer, K.; Koene, J.M.

    2007-01-01

    With the aim of integrating the physiology and evolutionary ecology of Lymnaea stagnalis (Linnaeus, 1758), we studied the effects of day length and food availability on the energy budget. Snails were assigned to two different photoperiods and three levels of food availability. The snails were kept i

  16. Food intake, growth, and reproduction as affected by day length and food availability in the pond snail Lymnaea stagnalis

    NARCIS (Netherlands)

    Maat, ter A.; Zonneveld, C.; Visser, de J.A.G.M.; Jansen, R.F.; Montagne-Wajer, K.; Koene, J.M.

    2007-01-01

    With the aim of integrating the physiology and evolutionary ecology of Lymnaea stagnalis (Linnaeus, 1758), we studied the effects of day length and food availability on the energy budget. Snails were assigned to two different photoperiods and three levels of food availability. The snails were kept

  17. Determination of the infection of Lymnaea-gedrosina to trematodes Larval in the water region of Khuzestan

    Directory of Open Access Journals (Sweden)

    Shamsi Noorpisheh

    2011-06-01

    Full Text Available Background & Objective: The province of Khuzestan with its wide geographical area and its tropical climate is susceptible for the maintenance of snails. One of the prevalent intermediate hosts for trematode in this area is the gasteropode snail, Lymnaea gedrosina. This study is the first research, undertaken to determine the infection rate, biological characteristics and Longevity Lymnaea gedrosina. Materials & Methods: A total of 6213 snails (Lymnaea gedrosina were examined, 770 snails were kept in identical natural condition in a set of several water bodies. Using two methods of cercarial shedding by light and crushing of snails were identified. Results: Overall, 107 snails (5% were infected with trematodes larval. The maximum and minimum infection rate Maravaneh 4, (44% - Ahvaz, Dezfull including Anjirak and Sidnoor (1.7% and 1% respectively. In addition, the maximum and minimum longevity time per Lymnaea gedrosina were respectively found to be in the spring and autumn. Conclusion: The results of this study could be utilized to plan control intermediate disease snails for the purpose of sanitation in the Khuzestan Province.

  18. Experimental Infection of Lymnaea ollula in Japan with Fasciola hepatica from the U.S.A.

    OpenAIRE

    Kawano, Junichi; Shimizu, Akira; Uji, Tatsuya; Kimura, Shige

    1987-01-01

    アメリカ産肝蛭(Fasciola hepatica)を日本産ヒメモノアラガイ(Lymnaea ollula)に感染させ, 感染後の発育について検討した。感染ミラシジウムはスポロシスト, レジアに順次発育し, 感染後36日及び62日にセルカリアの遊出が認められた。このことより, 日本産ヒメモノアラガイはアメリカ産肝蛭の中間宿主となり得ることが判明した。 / Snails of Lymnaea ollula in Japan were exposed to the miracidia of Fasciola hepatica obtained from the U.S.A. Larval development of F. hepatica, from the sporocyst to the redia, was observed in the infected snails. Cercariae were emerged from the snails on the 36th and 62nd post infection days. L. ollula in Japan may...

  19. Attraction to amino acids by Lymnaea acuminata, the snail host of Fasciola species.

    Science.gov (United States)

    Tiwari, F; Singh, D K

    2004-04-01

    Adult Lymnaea acuminata (average length 20-22 mm) were collected locally from lakes and low-lying submerged fields from Gorakhpur. The chemoattraction studies were made in round glass aquaria measuring 30 cm in diameter and filled to a depth of 10 mm with 500 ml dechlorinated tap water. Each aquarium was divided into four concentric zones. At the starting time of the assay 10 snails were placed on the circumference of outermost zone 0. Snail attractant pellets (SAP) were added simultaneously in the center of central zone 3. SAP of different amino acids were prepared at concentrations of 10, 20, 50, 80 and 100 mM/2% agar solution and, subsequently, spread to a uniform thickness of 5 mm. After cooling, SAP were cut in small pieces of 5 mm in diameter. Lymnaea acuminata's attraction to amino acids was studied using different amino acid concentrations in SAP. Pellets containing amino acids with non-polar R groups (proline and tryptophan), a charged polar group (arginine) and uncharged polar R groups (serine, citrulline and asparagine) were tested. The snails were more attracted to the uncharged polar R group amino acid serine than to other groups of amino acids. The preferred amino acid concentration was 80 mM. The attraction of snails to different amino acids was concentration dependent. Snails could discriminate amongst the different amino acids at > or = 50 mM.

  20. Attraction to amino acids by Lymnaea acuminata, the snail host of Fasciola species

    Directory of Open Access Journals (Sweden)

    Tiwari F.

    2004-01-01

    Full Text Available Adult Lymnaea acuminata (average length 20-22 mm were collected locally from lakes and low-lying submerged fields from Gorakhpur. The chemoattraction studies were made in round glass aquaria measuring 30 cm in diameter and filled to a depth of 10 mm with 500 ml dechlorinated tap water. Each aquarium was divided into four concentric zones. At the starting time of the assay 10 snails were placed on the circumference of outermost zone 0. Snail attractant pellets (SAP were added simultaneously in the center of central zone 3. SAP of different amino acids were prepared at concentrations of 10, 20, 50, 80 and 100 mM/2% agar solution and, subsequently, spread to a uniform thickness of 5 mm. After cooling, SAP were cut in small pieces of 5 mm in diameter. Lymnaea acuminata's attraction to amino acids was studied using different amino acid concentrations in SAP. Pellets containing amino acids with non-polar R groups (proline and tryptophan, a charged polar group (arginine and uncharged polar R groups (serine, citrulline and asparagine were tested. The snails were more attracted to the uncharged polar R group amino acid serine than to other groups of amino acids. The preferred amino acid concentration was 80 mM. The attraction of snails to different amino acids was concentration dependent. Snails could discriminate amongst the different amino acids at > or = 50 mM.

  1. Statistical refinements for data analysis of mollusc reproduction tests: an example with Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Holbech, Henrik

    Since 2012, European experts work towards the development and validation of an OECD test guideline for mollusc reproductive toxicity with the freshwater gastropod Lymnaea stagnalis. A ring-test involving six laboratories allowed studying reproducibility of results, based on survival and reproduct......Since 2012, European experts work towards the development and validation of an OECD test guideline for mollusc reproductive toxicity with the freshwater gastropod Lymnaea stagnalis. A ring-test involving six laboratories allowed studying reproducibility of results, based on survival...... and reproduction data of snails monitored over 56 days exposure to cadmium. A classical statistical analysis of data was initially conducted by hypothesis tests and fit of parametric concentrationresponse models. However, as mortality occurred in exposed snails, these analyses require to be refined, particularly...... was twofold. First, we refined the statistical analyses of reproduction data accounting for mortality all along the test period. The variable “number of clutches/eggs produced per individual-day” was used for EC x modelling, as classically done in epidemiology in order to account for the time...

  2. COLONIZACIÓN DE MOLUSCOS Y CRUSTÁCEOS EN RAÍCES DE MANGLE ROJO EN UNA LAGUNA COSTERA DE LA PUNTA NORTE DEL GOLFO DE MORROSQUILLO

    Directory of Open Access Journals (Sweden)

    PRÜSMANN JOHANNA

    2010-05-01

    Full Text Available Se evaluaron la colonización y sucesión de moluscos y crustáceos en un sustrato de raíces de mangle en tres estaciones en la ciénaga La Boquilla, Punta San Bernardo en la parte norte del Golfo de Morrosquillo. Para el seguimiento del proceso de colonización se ubicaron tres sitios en las márgenes occidental, norte y oriental, y se fijaron en cada estación seis raíces aéreas deshojadas de Rhizophora mangle. Luego de 76 y 200 días de exposición, se retiraron tres raíces de cada sitio y se identificaron los organismos por morfoespecie. Después de 200 días de exposición, se determinaron 19 especies de moluscos y cinco de crustáceos. El anfípodo Corophium sp. y el bivalvo Brachidontes exustus fueron las especies mas numerosas y agruparon una fracción muy importante de la totalidad de los individuos recolectados. La mayoría de las especies encontradas son típicas de la fauna acompañante de las raíces de mangle en el Caribe colombiano.

  3. Assessment of the FasciMol-ELISA in the detection of the trematode Fasciola hepatica in field-collected Galba cubensis: a novel tool for the malacological survey of fasciolosis transmission.

    Science.gov (United States)

    Alba, Annia; Vázquez, Antonio A; Sánchez, Jorge; Fraga, Jorge; Hernández, Hilda; Martínez, Elizabeth; Marcet, Ricardo; Figueredo, Mabel; Sarracent, Jorge

    2016-01-16

    Fasciolosis is one of the food-borne neglected trematodioses that has reemerged as a human disease while its effects on domestic animal health remains of significant economic consideration. Being snail-borne disease, the accurate and time-saving epidemiological surveillance of the transmission foci where infected lymnaeid snails occur could be essential to effectively focus or redirect control strategies. For this purpose, the first monoclonal antibody-based immunoenzymatic assay to detect Fasciola hepatica-infected snails (FasciMol-ELISA) was recently developed and showed a high sensitivity and specificity when tested in an experimental F. hepatica - Galba cubensis system. Here, we surveyed populations of G. cubensis occurring in western Cuba for the assessment of the FasciMol-ELISA in determining natural F. hepatica infection in this intermediate host. A multiplex PCR, previously developed to detect F. hepatica in G. cubensis, was used for sample classification. Snail dissection method was also employed as screening technique. A Χ(2) test and a Kappa index were calculated to evaluate the positivity and the level of agreement between the FasciMol-ELISA and the snail dissection methods with the multiplex PCR, respectively. Galba cubensis was found in nine out of 12 sampled localities of which four were positive for F. hepatica infection as detected by both immunoenzymatic and PCR-based assays. The overall prevalence was higher than the natural infection rates previously reported for Cuban G. cubensis (range from 4.1 to 7.42% depending on the screening method). No significant differences were found between FasciMol-ELISA and multiplex PCR when determining parasite positivity (Χ(2) = 6.283; P = 0.0981) whereas an excellent agreement was also noted (Kappa = 0.8224). Our results demonstrate the importance of malacological surveys in assessing parasite transmission risk and constitute an alert on the need of accurate measures to control fasciolosis in

  4. Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

    Directory of Open Access Journals (Sweden)

    Juan Francisco Sánchez Pérez

    2008-12-01

    Full Text Available El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso pertenece a la familia Poxvirus, virus ADN relacionados entre sí, que son infectivos para animales vertebrados e invertebrados. Las lesiones se contagian por contacto directo con personas infectadas o con objetos contaminados y suele afectar a la población en edad escolar, produciéndose en determinadas situaciones verdaderas epidemias. En noviembre de 2008 se recibió en el Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Región de Murcia una llamada telefónica del Servicio de Epidemiología de la misma consejería, en la que se comunicaba la existencia de aproximadamente 12-15 casos de niños afectados por molusco contagioso indicándose además, que las sospechas recaían sobre la piscina municipal cubierta de Alhama de Murcia. Inmediatamente se contactó con el personal responsable de la instalación, enviándoles un protocolo de actuaciones elaborado con información obtenida de diversas fuentes de información. Tras la búsqueda bibliográfica se seleccionó como indicador el parámetro ausencia de mohos y levaduras. Los resultados obtenidos en la toma de muestras de los artículos propios de la piscina mostraron ausencia de molusco contagioso, coincidiendo con la no aparición de más casos. Meses más tarde, en marzo de 2009, se detectaron de nuevo casos de niños afectados en otra piscina del municipio de Alcantarilla. Debido al éxito de la metodología utilizada en el incidente an- terior, se realizaron idénticas actuaciones, obteniéndose idénticos resultados. A la vista de los resultados obtenidos, el protocolo elaborado por este servicio se mostró efectivo para detener la aparición de más casos, puesto que no ocurrió ninguna incidencia posterior, y se

  5. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil

    OpenAIRE

    Francisco José Pegado Abílio; Takako Watanabe

    1998-01-01

    Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae), primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.The occurrence of Lymnaea Columella (Gastropoda: Lymnaeidae), first intermediate host of Fasciola hepatica, is recorded for the first time in the state of Paraíba, Brazil, associeted with aquatic macrophytes.

  6. El fenómeno 'El Niño' y los moluscos de la Costa peruana

    Directory of Open Access Journals (Sweden)

    1993-01-01

    Full Text Available LE PHÉNOMÈNE 'EL NIÑO' ET LES MOLLUSQUES DE LA CÔTE PÉRUVIENNE. Parmi les bio-indicateurs du phénomène El Niño, les mollusques littoraux présentent l'avantage de posséder un test calcaire susceptible d'être préservé aussi bien dans des amas coquilliers d'origine anthropique que dans des dépôts géologiques naturels. Du fait de la répartition des provinces zoogéographiques sur la côte péruvienne, et en raison des effets directs des anomalies océano-climatiques El Niño dans la région, il est donc logique de supposer que les coquilles de mollusques sub-actuelles ou fossiles puissent jouer un rôle important dans la reconstitution d'événements El Niño du passé. Dans cette optique, ont été analysés les indices de présence/absence de certaines espèces de bivalves et de gastéropodes dans des dépôts archéologiques et géologiques de la côte péruvienne, à la lumière de quelques observations menées lors des épisodes récents de 1982-1983 et 1986-1987. Cette récapitulation des données relatives aux épisodes El Niño des dernières années et aux enregistrements possibles des événements plus anciens, montre qu'il reste beaucoup à apprendre sur la dynamique du peuplement et l'écologie des mollusques en réponse à l'anomalie océanographique, et qu'une certaine prudence est de mise lorsque l'on souhaite reconstituer ce type d'anomalies dans le passé. Dans quelques cas, néanmoins, il est envisagé que des conditions océanographiques de type El Niño aient pu permettre, à l'Holocène comme durant certains interglaciaires du Pléistocène, le transport de larves d'organismes provenant de la Province Panaméenne, ou de la Zone de Transition de Paita, jusqu'aux côtes du centre et du sud du Pérou (Province Péruvienne. Entre otros bioindicadores del fenómeno El Niño, los moluscos litorales presentan la ventaja de tener un esqueleto carbonatado que suele preservarse tanto en conchales de origen antr

  7. Study on fungicide resistance of Pseudoperonospora cubensis to azoxystrobin%黄瓜霜霉菌对嘧菌酯抗药性的研究

    Institute of Scientific and Technical Information of China (English)

    张艳菊; 王莹; 党悦嘉; 柴洪庆

    2015-01-01

    Azoxystrobin is a strobilurin fungicide, it has a broad antimicrobial spectrum and high activity, but at the same time the agent also runs the risk of becoming a resistance agent. In order to understand the resistance of the cucumber downy mildew's (Pseudoperonospora cubensis) sensitivity to azoxystrobin, 36 cucumber downy mildew isolates were tested using the leaf disk floating method. The isolates were collected from 13 production areas over eight provinces:Heilongjiang, Jilin, Liaoning, Beijing, Shandong, Jiangsu, Hubei and Guangdong. EC50 of Pseudoperonospora cubensis to azoxy-strobin was 0.0107-0.2408μg·mL-1 and the average EC50 was 0.1004μg·mL-1. Of the 36 strains, 26 had a medium level of resistance, nine had low resistance, one was sensitive and none were highly resistant. The resistance level of Shandong Province strains to azoxystrobin was the highest and the resistance levels of other provinces' resistant strains to azoxystrobin were relatively low.%嘧菌酯为甲氧基丙烯酸酯类杀菌剂,具有杀菌谱广、杀菌活性高等优点,但同时该类药剂也属于高抗性风险药剂。为明确我国黄瓜主产区黄瓜霜霉菌对嘧菌酯的抗药性,采用叶盘漂浮法测定来自黑龙江、吉林、辽宁、北京、山东、江苏、湖北和广东8个省份13个黄瓜主产区36个黄瓜霜霉病菌(Pseudoperonospora cubensis)菌株对嘧菌酯的抗药性。黄瓜霜霉菌对嘧菌酯的EC50值为0.0107~0.2408μg·mL-1,平均EC50值为0.1004μg·mL-1。36个菌株中有26个中抗菌株、9个低抗菌株和1个敏感菌株,无高抗菌株。山东省菌株对嘧菌酯的抗性水平最高,其余省份菌株对嘧菌酯抗性水平相对较低。

  8. Prevalence of Cercariae Infection in Lymnaea auricularia (Linnaeus, 1758 in NorthWest of Iran

    Directory of Open Access Journals (Sweden)

    Abbas Imani-Baran

    2011-06-01

    Full Text Available The pond snail Lymnaea auricularia serves as an intermediate host for many digenian species. In West Azerbaijan province, northwestern Iran, the cercariae infection investigation was undertaken in L. auricularia from May to November 2010. Of 6759 collected Lymnaeid snails, 370(5.5% L. auricularia snails were identified. Cercariae infection was found in a number of 276 (74.56 % snails. The results showed that removed cercariae from L. auricularia belonged to Echinostomcercariae (96.38 % and Furcocercariae (3.62 % which were found in two out of 28 sites during the course of study. In summer and fall, the highest prevalence of cercariae infection was recorded for both identified cercariae. It is concluded that L. auricularia could be an important intermediate host of large group digenian trematodes in the region, which is necessary to take consideration in the control program of trematode infection.

  9. Non-ocular dermal photoreception in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Chono, Koji; Fujito, Yutaka; Ito, Etsuro

    2002-09-27

    Based on the results of previous behavioral experiments, researchers believe that sensitivity to light stimuli is not restricted to the eyes in the pond snail Lymnaea stagnalis. To determine the presence of a non-ocular dermal photoreception system and to examine the synaptic connections between this peripheral system and the central nervous system, we electrophysiologically examined the activities of the pedal nerves in L. stagnalis by light stimulation. The results demonstrated that light stimulation evokes non-ocular dermal photosensitive responses in the foot, that these responses exert inhibitory, afferent influences through the inferior pedal nerves to the pedal ganglia, and that these responses were independent of the ocular photoreception system in L. stagnalis.

  10. Toxicity of Bauhinia variegata and Mimusops elengi with plant molluscicides against Lymnaea acuminata

    Directory of Open Access Journals (Sweden)

    Kanchan Lata Singh

    2012-01-01

    Full Text Available Molluscicidal activity of binary combination of Bauhinia variegata and Mimusops elengi with other plant molluscicides Saraca asoca and Thuja orientalis against snail Lymnaea acuminata have been studied. It was observed that toxicity of binary combinations of plant molluscicides with other plant molluscicides were toxic against fresh water snail L. acuminata. Among all combinations of toxicity Mimusops elengi leaf + Saraca asoca bark (24h LC50: 98.25 mg/l; 96h LC50: 40.40 mg/l and Bauhinia variegata leaf powder + Saraca asoca leaf (24h LC50: 123.98 mg/l; 96h LC50: 57.91 mg/l was more toxic than other binary combinations of plant molluscicides. Mimusops elengi leaf powder + Saraca asoca leaf powder and Bauhinia variegata leaf powder + Saraca asoca leaf powder are more potent molluscicides.

  11. Seasonal transmission of Fasciola hepatica in cattle and Lymnaea (Fossaria) humilis snails in central Mexico.

    Science.gov (United States)

    Cruz-Mendoza, I; Ibarra-Velarde, F; Quintero-Martínez, M T; Naranjo-García, E; Lecumberri-López, J; Correa, D

    2005-03-01

    A 19-month study on the prevalence of fasciolosis in 30 naturally infected cows, the presence of infected and non-infected Lymnaea (Fossaria) humilis snails, and variation in soil temperature and humidity is reported. The prevalence of fasciolosis in cattle declined from around 50% in March to 30% in July, then, it increased from August, reaching a plateau of 100% in November-January, before gradually declining thereafter. A rise in soil humidity and temperature in June and July, respectively, which peaked between August and November was observed. In July, L. (F.) humilis snails appeared, but the infection could only be found in these in August and November. The number of infected snails did not reflect the infestation rate in cows, even though the infestation kinetics in both hosts behaved as predicted from the life cycle of the parasite.

  12. Influence of shell size of Lymnaea columella on infectivity and development of Fasciola hepatica.

    Science.gov (United States)

    Coelho, L H L; Guimarães, M P; Lima, W S

    2008-03-01

    Experimental infections of Lymnaea columella with Fasciola hepatica were carried out to determine the influence of shell size on the infection rate and on the outcome of rediae and cercariae. Snails were divided into seven groups according to shell size: 2-4 mm, 5-6 mm, 7-8 mm, 9-10 mm, 11-12 mm, 13-14 mm and 15 mm or more. One hundred snails in each group were infected by using four miracidia for each snail. Snails with larger shell size showed a lower infection rate, the groups presenting the highest (79%) and lowest (2%) proportions of positives being those of 5-6 mm and 15 mm or more, respectively. Cercariae were present in 21% of them at 31 days post-infection, and cercarial shedding was observed 61 days post-infection. It was concluded that there is a non-linear negative association between shell size and infection rate.

  13. Behavioural responses of the snail Lymnaea acuminata to carbohydrates and amino acids in bait pellets.

    Science.gov (United States)

    Agrahari, P; Singh, D K

    2010-12-01

    Snail control could play an important role in programmes against fascioliasis, especially if the methods used for molluscicide delivery could be improved, such as by the development of bait formulations containing both an effective attractant and a molluscicide, to ensure good levels of contact between the molluscicide and the target snail populations. In a recent study, the attractiveness to Lymnaea acuminata (an intermediate host of the digenean trematode Fasciola gigantica) of potential components of snail-attractant pellets was investigated. Carbohydrates (glucose, maltose, sucrose or starch, each at 10 mM) and amino acids (citrulline, tryptophan, proline or serine, each at 20 mM), were tested in aquaria, with the snails initially placed 22.5, 30 or 45 cm from an agar pellet containing the component under test. Under these conditions, starch and proline emerged as the strongest attractants for L. acuminata, followed by maltose and serine.

  14. The presence of predators modifies the larval development of Fasciola hepatica in surviving Lymnaea truncatula.

    Science.gov (United States)

    Rondelaud, D; Vignoles, P; Dreyfuss, G

    2002-06-01

    Experimental infections of Lymnaea truncatula with Fasciola hepatica were performed to study the consequences of the presence of predators (sciomyzid larvae or zonitid snails) on the characteristics of larval F. hepatica development in surviving snails. Controls consisted of infected snails that were not subjected to predators. Compared to controls, the survival rate at day 30 post-exposure, the duration of cercarial shedding, and the number of cercariae shed by surviving snails were significantly lower when predators were present in snail breeding boxes, whatever the type of predator used. In contrast, the prevalences of Fasciola infections in snails, and the length of time between exposure and the onset of cercarial shedding showed no significant variation. The progressive development of a stress reaction in surviving snails against predators during the first 30 days of experimental exposure to F. hepatica would influence snail survival during the cercarial shedding period and, consequently, the number of cercariae shed by the snails.

  15. Fasciola gigantica: the growth and larval productivity of redial generations in the snail Lymnaea truncatula.

    Science.gov (United States)

    Dar, Y; Vignoles, P; Rondelaud, D; Dreyfuss, G

    2002-04-01

    Bimiracidial infections of French Lymnaea truncatula with a Madagascan isolate of Fasciola gigantica were carried out under laboratory conditions to study the growth of rediae and their larval productivity in relation to the different redial generations. The total numbers of rediae and their mean lengths significantly increased with the duration of infection until day 49 post-exposure (p.e.). Significant differences in the lengths between the different redial generations were noted. At day 49 p.e. (at 20 degrees C), the cercariae were produced by the first redial generation, while the productivity of other redial groups was delayed. This last finding shows a slow larval development of this Madagascan isolate of F. gigantica in this French population of L. truncatula.

  16. Detection of Lymnaea columella infection by Fasciola hepatica through Multiplex-PCR.

    Science.gov (United States)

    Magalhães, Kelly Grace; Passos, Liana Konovaloff Jannotti; Carvalho, Omar dos Santos

    2004-06-01

    From complete mitochondrial DNA sequence of Fasciola hepatica available in Genbank, specific primers were designed for a conserved and repetitive region of this trematode. A pair of primers was used for diagnosis of infected Lymnaea columella by F. hepatica during the pre-patent period simultaneously with another pair of primers which amplified the internal transcribed spacer (ITS) region of rDNA from L. columella in a single Multiplex-PCR. The amplification generated a ladder band profile specific for F. hepatica. This profile was observed in positive molluscs at different times of infection, including adult worms from the trematode. The Multiplex-PCR technique showed to be a fast and safe tool for fascioliasis diagnosis, enabling the detection of F. hepatica miracidia in L. columella during the pre-patent period and identification of transmission areas.

  17. Juveniles of Lymnaea 'smart' snails do not perseverate and have the capacity to form LTM.

    Science.gov (United States)

    Shymansky, Tamila; Protheroe, Amy; Hughes, Emily; Swinton, Cayley; Swinton, Erin; Lukowiak, Kai S; Phillips, Iain; Lukowiak, Ken

    2017-02-01

    Previously, it was concluded that the nervous systems of juvenile snails were not capable of mediating long-term memory (LTM). However, exposure and training of those juvenile snails in the presence of a predator cue significantly altered their ability to learn and form LTM. In addition, there are some strains of Lymnaea which have been identified as 'smart'. These snails form LTM significantly better than the lab-bred strain. Here, we show that juveniles of two smart snail strains not only are capable of associative learning but also have the capacity to form LTM following a single 0.5 h training session. We also show that freshly collected 'wild' 'average' juveniles are also not able to form LTM. Thus, the smart snail phenotype in these strains is expressed in juveniles.

  18. Detection of Lymnaea columella infection by Fasciola hepatica through Multiplex-PCR

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    Kelly Grace Magalhães

    2004-06-01

    Full Text Available From complete mitochondrial DNA sequence of Fasciola hepatica available in Genbank, specific primers were designed for a conserved and repetitive region of this trematode. A pair of primers was used for diagnosis of infected Lymnaea columella by F. hepatica during the pre-patent period simultaneously with another pair of primers which amplified the internal transcribed spacer (ITS region of rDNA from L. columella in a single Multiplex-PCR. The amplification generated a ladder band profile specific for F. hepatica. This profile was observed in positive molluscs at different times of infection, including adult worms from the trematode. The Multiplex-PCR technique showed to be a fast and safe tool for fascioliasis diagnosis, enabling the detection of F. hepatica miracidia in L. columella during the pre-patent period and identification of transmission areas.

  19. Studies on the survival and development of field-caught snail Lymnaea rubiginosa in the laboratory

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    S Widjajanti

    1998-10-01

    Full Text Available Lymnaea rubiginosa was collected from two habitats in order to observe their survival and growth rate including their egg production, hatching time and the time they needed to reach maturity. One of the habitat is rice fields in Bogor (subdistricts of Ciomas and Ciampea and the other is a pond in Bogor Botanical Garden. In the laboratory those snails were kept in separate aquarium and grouped according to their shell length. The result showed that the longer the snail length the shorter their survival rate and less egg production. Moreover, the snails collected from rice fields were infected with Echinostoma sp. And Chaetogaster sp., while the snails from the pond were only infected with Chaetogaster sp. The hatching time is between 10-14 days, and to reach maturity, with shell length about 1 cm, they need about 6 weeks.

  20. Evidence for genetic influences on neurotransmitter content of identified neurones of Lymnaea stagnalis.

    Science.gov (United States)

    Audesirk, G; Audesirk, T; McCaman, R E; Ono, J K

    1985-01-01

    Neurotransmitter content was measured in two identified giant neurones in isogenic and wild-type populations of the freshwater pond snail Lymnaea stagnalis. The paired serotonergic cerebral giant neurones (LC1 and RC1) have higher transmitter levels and less variability in inbred animals than in wild-type animals. The transmitter content of the unpaired dopaminergic right pedal giant neurone (RPeD1) does not differ between inbred and wild-type animals in either level or variability. It is proposed that serotonin content of the cerebral giant neurones is under partial genetic control, and that animals of the wild-type population may possess a number of different alleles for the genes influencing serotonin levels. Inbreeding resulted in fixation of an allele promoting high serotonin levels. This particular wild-type population is probably already isogenic for genes influencing dopamine content in the right pedal giant neurone.

  1. Amine-containing neurons in the brain of Lymnaea stagnalis: distribution and effects of precursors.

    Science.gov (United States)

    Audesirk, G

    1985-01-01

    Glyoxylic acid-induced fluorescence in whole-brain preparations of the central nervous system of the freshwater pond snail, Lymnaea stagnalis, was used to map the distribution of serotonin-and dopamine-containing neurons. Serotonin and dopamine were easily distinguishable by differences in color of fluorescence. Serotonin-containing neurons were consistently found in the cerebral, pedal, right parietal and visceral ganglia. Dopamine-containing neurons were found in the pedal, and buccal ganglia. Prior incubation of brains in 5-hydroxytryptophan (5-HTP), the immediate precursor to serotonin, produced serotonin-like fluoresence in neurons which do not normally fluoresce. These neurons thus probably possess specific uptake mechanisms for 5-HTP. Since 5-HTP itself fluoresces yellow, the glyoxylic acid technique cannot determine if these neurons contain the enzyme aromatic amino acid decarboxylase, which converts 5-HTP to serotonin, or merely fluoresce because of the 5-HTP taken into the cells.

  2. Molluscicidal activity of Morus nigra against the freshwater snail Lymnaea acuminata

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    Farheen Hanif

    2012-01-01

    Full Text Available The molluscicidal activity of Morus nigra fruit, bark and leaf powder against the snail Lymnaea acuminata was time and concentration dependent. Toxicity of fruit powder (96h LC50: 166.92 mg/L was more pronounced in comparison to bark powder (96h LC50: 173.17 mg/L and leaf powder (96h LC50: 173.69 mg/L. Ethanolic extracts of M. nigra fruit, bark and leaf was more toxic than their other organic solvent extracts. The molluscicidal activity of ethanolic extract of M. nigra fruit powder (24h LC50: 116.23 mg/L was more effective than the ethanolic extract of bark powder (24h LC50: 154.41 mg/L and leaf powder (24h LC50: 139.80 mg/L. The 96h LC50 of column-purified fraction of M. nigra fruit powder was, 10.03 mg/L whereas that of bark and leaf powder was 8.69 mg/L and 4.97 mg/L, respectively. Column and thin layer chromatography analysis demonstrates that the active molluscicidal component in M. nigra is quercetin (96h LC50: 1.11 mg/L, apigenin (96h LC50: 1.92 mg/L and morusin (96h LC50: 2.12 mg/L, respectively. Co-migration of quercetin (Rf 0.49, apigenin (Rf 0.51 and morusin (Rf 0.52 with column-purified fruit, bark and leaf of M. nigra on thin layer chromatography demonstrates same Rf value. The present study indicates that M. nigra may be used as potent source of molluscicides against the snail Lymnaea acuminata.

  3. Morphological and ecological studies on Lymnaea natalensis the snail vector of Fasciola gigantica in Egypt.

    Science.gov (United States)

    el-Dafrawy, Shadia M

    2002-08-01

    Lymnaea natalensis were collected from several localities in Giza Governorate (El-Mansouria, Kafr Hakim and The Nile). The collected snails were examined for cercarial shedding and measurement of shell was carried out using a virner caliper. A total of 217 Lymnaea was collected from all habitats and 24 snails were found to shed Fasciola gigantica cercariae with infection rate 11.1%. The ratio of shell height to shell width (H/W) ranged 1.7-2.1. The ratio between length of aperture to shell height (A/H) was almost constant ranged 0.7-0.8. While the ratio between length of aperture and shell width (A/W) ranged from to 1.8. There was a significant positive correlation between shell height and both shell width and length of aperture (p<0.001). The same relation was clearly indicated between shell width and length of aperture. Also, when the aperture length increased the ratio between height and width increased (p<0.05). While, the following ratios (H/W), (A/H) and (A/W) remained somewhat constant irrespective to the number of whorls. There was a positive correlation between number of whorls and each of aperture length, shell length and shell height. On maintaining L. natalensis in different pH values, the results showed that at pH 3 and pH 11, all snails maintained at these pH values died after one day of maintenance. While snails survived and laid eggs in the range of pH 5-9.

  4. Distinción taxonómica de los moluscos de fondos blandos del Golfo de Batabanó, Cuba

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    Norberto Capetillo-Piñar

    2015-11-01

    Full Text Available La distinción taxonómica es una medida de diversidad que presenta una serie de ventajas que dan connotación relevante a la ecología teórica y aplicada. La utilidad de este tipo de medida como otro método para evaluar la biodiversidad de los ecosistemas marinos bentónicos de fondos blandos del Golfo de Batabanó (Cuba se comprobó mediante el uso de los índices de distinción taxonómica promedio (Delta+ y la variación en la distinción taxonómica (Lambda+ de las comunidades de moluscos. Para este propósito, se utilizaron los inventarios de especies de moluscos bentónicos de fondos blandos obtenidos en el periodo 1981-1985 y en los años 2004 y 2007. Ambos listados de especies fueron analizados y comparados a escala espacial y temporal. La composición taxonómica entre el periodo y años estudiados se conformó de 3 clases, 20 órdenes, 60 familias, 137 géneros y 182 especies, observándose, excepto en el nivel de clase, una disminución no significativa de esta composición en 2004 y 2007. A escala espacial se detectó una disminución significativa en la riqueza taxonómica en el 2004. No se detectaron diferencias significativas en Delta+ y Lambda+ a escala temporal, pero si a escala espacial, hecho que se puede atribuir al efecto combinado del incremento de las actividades antropogénicas en la región con los efectos inducidos por los huracanes. Estos resultados sugieren que el par de índices Delta+ y Lambda+ son buenos descriptores de la biodiversidad de las comunidades de moluscos bentónicos de fondos blandos del Golfo de Batabanó.

  5. Natural prevalence in Cuban populations of the lymnaeid snail Galba cubensis infected with the liver fluke Fasciola hepatica: small values do matter.

    Science.gov (United States)

    Vázquez, Antonio A; Sánchez, Jorge; Alba, Annia; Pointier, Jean-Pierre; Hurtrez-Boussès, Sylvie

    2015-11-01

    Natural infections of lymnaeid snails by Fasciola hepatica are of primary importance to study transmission. Also, infected snails in the field can be used to explore the existing compatibility in host-parasite interactions. This paper aimed to describe the infection rate of Galba cubensis populations in fasciolosis transmission areas. Eight sites were sampled in western Cuba and 24 infected snails at six sites were found. The mean prevalence was 2.94% and the maximum value was 11.4%. The intensity of parasite infection was assessed as the number of rediae inside a single snail. High variation within the sites examined was observed, but a maximum of 76 rediae was recovered from one individual. Although the presence of two other trematode families (Schistosomatidae and Paramphistomatidae) was discovered in dissected individuals, no co-infection with F. hepatica was observed. This is the first time a study of natural prevalence of F. hepatica infection is carried out in Cuba, considered a hyper endemic country for bovine fasciolosis. Our results suggest that fasciolosis transmission may occur even when the number of infected snails remains relatively low.

  6. Environmental Persistence and Infectivity of Oocysts of Two Species of Gregarines, Blabericola migrator and Blabericola cubensis (Apicomplexa: Eugregarinida: Blabericolidae), Parasitizing Blaberid Cockroaches (Dictyoptera: Blaberidae).

    Science.gov (United States)

    Clopton, Richard E; Steele, Shelby M; Clopton, Debra T

    2016-04-01

    For apicomplexan parasites using an oral-fecal transmission route with significant environmental exposure, the environmental persistence and infectivity of the oocyst has a direct impact on local infection dynamics, including the ability to withstand extended periods without readily available hosts. Herein we quantify the environmental persistence and infectivity of the oocysts of 2 septate gregarine species at controlled temperature and humidity and demonstrate that they can persist over multiple generational time spans. Species of Blabericola generally complete their endogenous life cycles from oocyst to oocyst within 10 days. The median residual environmental oocyst lifetime for Blabericola oocysts in this study is 21-28 days, but a significant number of oocysts of Blabericola migrator persisted and remained infective in the environment for up to 39 days while those of Blabericola cubensis persisted and remained infective for up to 92 days. Although long-lived relative to their own generational time, the oocysts of Blabericola species infecting cockroaches are short-lived relative to gregarines infecting tenebrionid beetles. For these gregarines, oocysts can persist in the environment and remain infective for up to 787 days. Mechanistically, environmental persistence and infectivity are probably energy-limited phenomena related to the amount of stored amylopectin and the basal metabolic rate of quiescent oocysts.

  7. Intermediate and long-term memories of associative learning are differentially affected by transcription versus translation blockers in Lymnaea.

    Science.gov (United States)

    Sangha, Susan; Scheibenstock, Andi; McComb, Chloe; Lukowiak, Ken

    2003-05-01

    Aerial respiratory behaviour in the pond snail, Lymnaea stagnalis, can be operantly conditioned. This associative learning then undergoes consolidation into a long-lasting memory which, depending on the training procedure used, causes intermediate-term memory (ITM; lasting 3 h) or long-term memory (LTM; lasting >6 h) to be formed. We determined the differential susceptibility of these two forms of memory to translation and transcription blockers. The injection of a translation blocker, Anisomycin, 2.5 h before training prevents the establishment of both ITM and LTM. On the other hand, injection of the transcription blocker Actinomycin D, 2.5 h before training, did not prevent the establishment of ITM, but did, however, prevent LTM formation. Thus in Lymnaea, following associative learning, both ITM and LTM are dependent on new protein synthesis. ITM appears to be dependent on protein synthesis from preexisting transcription factors, whilst LTM is dependent on protein synthesis from new transcription messages.

  8. Bait Formulations of Chlorophyllin against Infected/Uninfected Lymnaea acuminata in Red and Sunlight

    OpenAIRE

    Navneet Kumar; Vinay Kumar Singh

    2015-01-01

    Control of snail population is an important tool in fasciolosis control programme. In order to achive this objective the method of bait formulation containing an attractant and a molluscicide is an appropriate approach to ensure the death of host snail. Chlorophyllin bait pellets were prepared by addition of attractants starch (10 mM)/serine (20 mM) and Chlorophyllin 2% agar solution. These baits were used against host snail Lymnaea acuminata. The behavioral response of snail against attracta...

  9. First report of Lymnaea cousini Jousseaume, 1887 naturally infected with Fasciola hepatica (Linnaeus, 1758) (Trematoda: Digenea) in Machachi, Ecuador.

    Science.gov (United States)

    Villavicencio, Angel; Vasconcellos, Mauricio Carvalho de

    2005-11-01

    We report the first finding of Lymnaea cousini naturally infected with Fasciola hepatica in Ecuador. A sample of 70 snails was collected in April 2005 from a wetland located in a valley at approximately 3000 m a.s.l., near the locality of Machachi, Pichincha Province. The prevalence of natural infection in L. cousini was 31.43%, which is the highest value ever recorded for naturally infected lymnaeid species.

  10. First report of Lymnaea cousini Jousseaume, 1887 naturally infected with Fasciola hepatica (Linnaeus, 1758 (Trematoda: Digenea in Machachi, Ecuador

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    A Ángel Villavicencio

    2005-11-01

    Full Text Available We report the first finding of Lymnaea cousini naturally infected with Fasciola hepatica in Ecuador. A sample of 70 snails was collected in April 2005 from a wetland located in a valley at approximately 3000 m a.s.l., near the locality of Machachi, Pichincha Province. The prevalence of natural infection in L. cousini was 31.43%, which is the highest value ever recorded for naturally infected lymnaeid species.

  11. Ocorrência de infecção natural de Fasciola hepatica Linnaeus, 1758 em Lymnaea columella Say, 1817 no Vale do Paraíba, SP, Brasil Natural infection by Fasciola hepatica in Lymnaea columella in the Paraíba river valley, S. Paulo, Brazil

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    Marlene Tiduko Ueta

    1980-06-01

    Full Text Available Foram registradas em Piquete, no vale do rio Paraíba do Sul (SP, Brasil, taxas de 1,22% e 0,14% de infecção natural em Lymnaea columella, por Fasciola hepatica. Em um único exemplar de Lymnaea columella dentre os 1.052 examinados, foram observadas rédias com xifidiocercárias, rédias com cercárias de Fasciola hepatica e metacercárias de Echinostomatidae.Infection rates of 1.22% and 0.14% were obtained in Lymnaea columella snails naturally infected by Fasciola hepatica. Samples of the snails were collected in Piquete, a municipality of Paraíba do Sul, a river valley area in the State of S. Paulo. Also observed was one of the 1052 specimen of the Lymnaea columella rediae which had xiphidiocercariae and rediae with Fasciola hepatica cercariae and metacercariae of Echinostomatidae.

  12. Dinámica de la microflora contaminante en el molusco Aulacomya ater choro crudo y procesado en cebiche: 2.- análisis cualitativo.

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    Juana Coha

    2014-06-01

    Full Text Available En 64 muestras (1,152 especímenes del molusco Aulacomya ater "choro" de los mercados de Lima y Callao, se aislaron especies más representativas de tres principales grupos bacterianos: Entéricos, Enterococos y además, Micrococos. El porcentaje elevado de Escherichia coli en choros crudos (etapa a y "cebiche" (etapa c reafirman, como en el Estudio Cuantitativo, contaminación fecal humana; en menor cuantía, especies de Enterocococos, únicamente en choros crudos. Es notable la desigualdad de frecuencia de E. coli, Streptococcus del grupo D de Lancenfield y Staphylococcus aureus entre las etapas a y e; en el que este último microorganismo se manifiesta con mayor densidad en la etapa de "cebiche", como consecuencia de la manipulación de los aditivos.

  13. Dinámica de la microflora contaminante en el molusco Aulacomya ater choro crudo y procesado en cebiche: 1.- anallsis cuantitativo.

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    Juana María Coha

    2014-06-01

    Full Text Available Se ha determinado, cuantitativamente, presencia de organismos Coliformes y Enterococos en el molusco Aulacomya ater "choro", como índice de contaminación entérica humana, en cada etapa de su preparación hasta "cebiche". Se han pracesado 1,152 especímenes de mercados de Lima y Callao. Los resultados reportan mayores promedios de contaminación para ambos grupos m'crobianos, en choros crudos (etapa a, de mercados ubicados en zonas de menor higiene y mayor población. La temperatura ambiental en meses de verano, demuestra gran incremento de esta microflora. La temperatura de cocción de la fracción previa al "cebiche" (etapa b, efímina totalmente los contaminantes, reapareciendo Coliformes en éste (etapa el, por los aditivos. El jugo de limón no actuó como bactericida eficaz.

  14. Characterisation of fascioliasis lymnaeid intermediate hosts from Chile by DNA sequencing, with emphasis on Lymnaea viator and Galba truncatula.

    Science.gov (United States)

    Artigas, Patricio; Bargues, M Dolores; Mera y Sierra, Roberto L; Agramunt, Veronica H; Mas-Coma, Santiago

    2011-12-01

    In South America, Fasciola hepatica infection poses serious health problems in both humans and livestock. In Chile, the medical impact appears yearly stable and mainly concentrated in central regions, where the veterinary problem is highlighted by higher animal prevalences. Studies were undertaken by rDNA ITS-2 and ITS-1 and mtDNA cox1 sequencing to clarify the specific status of the lymnaeids, their geographical distribution and fascioliasis transmission capacity in Chile, by comparison with other American countries and continents. Results change the lymnaeid scenario known so far. The lymnaeid fauna of mainland Chile shows to be poor, including only two authochthonous species, Lymnaea viator and Pectinidens diaphana, and a third introduced species of Palaearctic origin Galba truncatula. Both Lymnaea lebruni and Lymnaea patagonica proved to be synonyms of P. diaphana. G. truncatula appears to have always been confused with L. viator and seems distributed from Región VI to Región IX, overlapping with human endemic areas. DNA sequencing results suggest that the absence of correlation between remote sensing data and disease prevalences could be due to transmission capacity differences between L. viator and G. truncatula. Results furnish a new baseline on which to undertake future appropriate studies on transmission, epidemiology and control.

  15. An expressed sequence tag survey of gene expression in the pond snail Lymnaea stagnalis, an intermediate vector of trematodes [corrected].

    Science.gov (United States)

    Davison, A; Blaxter, M L

    2005-05-01

    The pond snail Lymnaea stagnalis is an intermediate vector for the liver fluke Fasciola hepatica, a common parasite of ruminants and humans. Yet, despite being a disease of medical and economic importance, as well as a potentially useful comparative tool, the genetics of the relationship between Lymnaea and Fasciola has barely been investigated. As a complement to forthcoming F. hepatica expressed sequence tags (ESTs), we generated 1320 ESTs from L. stagnalis central nervous system (CNS) libraries. We estimate that these sequences derive from 771 different genes, of which 374 showed significant similarity to proteins in public databases, and 169 were similar to ESTs from the snail vector Biomphalaria glabrata. These L. stagnalis ESTs will provide insight into the function of the snail CNS, as well as the molecular components of behaviour and response to parasitism. In the future, the comparative analysis of Lymnaea/Fasciola with Biomphalaria/Schistosoma will help to understand both conserved and divergent aspects of the host-parasite relationship. The L. stagnalis ESTs will also assist gene prediction in the forthcoming B. glabrata genome sequence. The dataset is available for searching on the world-wide web at http://zeldia.cap.ed.ac.uk/mollusca.html.

  16. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil Occurrence of Lymnaea columella (Gastropoda: Lymnaeidae, first intermediate host of Fasciola hepatica, for the state of Paraíba, Brazil

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    Francisco José Pegado Abílio

    1998-04-01

    Full Text Available Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.The occurrence of Lymnaea Columella (Gastropoda: Lymnaeidae, first intermediate host of Fasciola hepatica, is recorded for the first time in the state of Paraíba, Brazil, associeted with aquatic macrophytes.

  17. Estudo morfométrico da concha de Lymnaea columella say, 1817 (Mollusca, Gastropoda, Pulmonata

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    Marlene T. Ueta

    1980-12-01

    Full Text Available Foram estudadas variações morfométricas de conchas de L. columella, provenientes de dez criadouros localizados nos seguintes municípios do Estado de São Paulo: - Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. Foram analisados os diferentes tipos de ambientes onde as limneas são encontradas com maior freqüência, estabelecendo-se a época do ano com maior abundância em espécimes, que correspondeu aos meses de julho a outubro. As medidas nas conhas dos diferentes criadouros referiram-se ao comprimento e largura da concha, comprimento e largura da abertura, comprimento da espira e número de voltas. Foram estabelecidos os coeficientes de correlação e de regressão e realizadas análises de variância entre as medidas tomadas e os índices obtidos da relação entre largura/comprimento da concha. Estas conchas foram comparadas com as de L. columella, L. viator, L. cubensis da coleção do Museu Nacional do Rio de Janeiro. Para a maioria das medidas as conchas mostraram proporções constantes, embora apresentassem diferenças em relação ao desenvolvimento. A maior variação foi observada em relação ao comprimento da espira. As variações morfométricas das conchas foram relacionadas com alguns fatores externos como pH, alcalinidade, dureza e teor da água. Aparentemente apenas a dureza total da água influiu na consistência das conchas.

  18. Verspreiding en habitats van Lymnaea natalensis, tussengasheerslak van die lewerbot Fasciola gigantica, in Suid-Afrika

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    K. N. de Kock

    2001-09-01

    Full Text Available Hierdie artikel fokus op die geografiese verspreiding en die habitats van Lymnaea natalensis, die slaktussengasheer van die lewerbot, Fasciola gigantica, soos gereflekteer deur die vindplekke van sy 4 552 monsters wat tans in die Nasionale Varswaterslakversameling (NVV van Suid-Afrika op rekord is. Alhoewel hierdie spesie in’n verskeidenheid van waterliggame aangetref is, was die meerderheid van die monsters (±70% afkomstig vanuit riviere, spruite en damme en is die water in 70.8% van die gevalle as standhoudend en in 71.8% van die gevalle as stadigvloeiend, of staande beskryf.  Die resultate van lewenstabeleksperimente deur verskeie outeurs het daarop gedui dat temperatuur ’n minder belangrike bepalende faktor in sy geografiese verspreiding blyk te wees, maar dat die beskikbaarheid van standhoudende water deurslaggewend vir sy voorkoms in ’n gegewe habitat mag wees. Hierdie resultate strook met die bevinding dat slegs 7.5% van die monsters van hierdie spesie in die NVV in habitats wat as seisoenaal beskryf is, versamel is. Verder bied dit’n logiese verklaring vir die sporadiese voorkoms, of totale afwesigheid van hierdie spesie in die droër streke van Suid-Afrika.  Opgaardamme en besproeiingsnetwerke dra grootliks by tot die skepping van permanente habitats wat geskik sou wees vir L. natalensis.  As tussengasheer vir een van die lewerbotspesies wat reeds ’n ekonomiese faktor in Suid-Afrika is, is dit ’n aspek waarmee beslis rekening gehou behoort te word in die beplanning en konstruksie van nuwe besproeiingsprojekte.AbstractDistribution and habitats of Lymnaea natalensis, snail intermediate host of the liver fluke Fasciola gigantica, in South Africa This paper focuses on the geographical distribution and the habitats of Lymnaea natalensis, the snail intermediate host of the liver fluke, Fasciola gigantica, as reflected by the collection sites of its 4 552 samples currently on record in the National Freshwater Snail Collection

  19. Presencia de moluscos tropicales de la provincia panameña en la costa central del Perú y su relación con los eventos "El Niño"

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    Carlos Paredes

    2014-06-01

    Full Text Available Se reporta el hallazgo de moluscos cuya distribución conocida se encuentra dentro de los límites de la Provincia Panameña, en diversas localidades de la Provincia Peruana entre los años 1972 y 1994, período en el que se presentaron varios eventos "El Niño". Fue posible determinar 15 especies de moluscos que ampliaron su distribución: Pteria stema, Orobitella peruviana, Cryptornya califomica, Cerithium (T stercusmuscarum, Malea ringens, Hexaplex brassica, Thais styllmanberryi, T (M. triangularis, T (T callaoensis, Acanthina brevidentata, Purpura pansa, Neorapana muricata, Anachis (C. nigricans, Cancellaria (C. decussata y C. (B. chrysostorna. Se postula una variabilidad en los límites de las provincias biogeográficas de la costa peruana, controlada por el ENSO.

  20. Responses of freshwater molluscs to environmental factors in Southern Brazil wetlands Respostas de moluscos límnicos a fatores ambientais em áreas úmidas do sul do Brasil

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    L. Maltchik

    2010-08-01

    Full Text Available Freshwater molluscs play an important role in aquatic ecosystems, providing food for many fish species and vertebrates. Investigations on factors that determine mollusc species richness and distribution in wetland systems are scarce in the Neotropical region. The main goal of this study was to determine how much variation in mollusc richness and composition is explained by area, hydroperiod, altitude, water conductivity, and dominant aquatic vegetation. This survey was performed in an extensive area of a Neotropical region (~280,000 km² in southern Brazil, with a large number of wetland systems (111 and covering a wide gradient of altitude and wetland surface area. The mollusc richness was positively associated with wetland area and negatively associated with altitude. The richness and composition of the freshwater molluscs were similar between permanent and intermittent wetlands and it did not differ significantly between aquatic bed and emergent wetlands. The first three axes of CCA explained 16.2% of the total variation in the composition of the freshwater mollusc observed. The variation in the composition had a correlation with wetland area, altitude and water conductivity. Our results showed that the wetlands are important habitats for molluscs in southern Brazil, and that the richness and the composition of molluscs were associated with area, altitude, water conductivity and dominant vegetation.Moluscos límnicos desempenham um papel importante em ecossistemas aquáticos, fornecendo alimento para diversos peixes e vertebrados. Investigações sobre os fatores que determinam a riqueza e a distribuição das espécies de moluscos em áreas úmidas são escassos na região neotropical. O principal objetivo deste estudo foi determinar a variação na riqueza e na composição de moluscos em função da área, hidroperíodo, altitude, condutividade da água e tipo de vegetação aquática dominante. Este estudo foi desenvolvido em uma extensa

  1. Memory trace in feeding neural circuitry underlying conditioned taste aversion in Lymnaea.

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    Etsuro Ito

    Full Text Available BACKGROUND: The pond snail Lymnaea stagnalis can maintain a conditioned taste aversion (CTA as a long-term memory. Previous studies have shown that the inhibitory postsynaptic potential (IPSP evoked in the neuron 1 medial (N1M cell by activation of the cerebral giant cell (CGC in taste aversion-trained snails was larger and lasted longer than that in control snails. The N1M cell is one of the interneurons in the feeding central pattern generator (CPG, and the CGC is a key regulatory neuron for the feeding CPG. METHODOLOGY/PRINCIPLE FINDINGS: Previous studies have suggested that the neural circuit between the CGC and the N1M cell consists of two synaptic connections: (1 the excitatory connection from the CGC to the neuron 3 tonic (N3t cell and (2 the inhibitory connection from the N3t cell to the N1M cell. However, because the N3t cell is too small to access consistently by electrophysiological methods, in the present study the synaptic inputs from the CGC to the N3t cell and those from the N3t cell to the N1M cell were monitored as the monosynaptic excitatory postsynaptic potential (EPSP recorded in the large B1 and B3 motor neurons, respectively. The evoked monosynaptic EPSPs of the B1 motor neurons in the brains isolated from the taste aversion-trained snails were identical to those in the control snails, whereas the spontaneous monosynaptic EPSPs of the B3 motor neurons were significantly enlarged. CONCLUSION/SIGNIFICANCE: These results suggest that, after taste aversion training, the monosynaptic inputs from the N3t cell to the following neurons including the N1M cell are specifically facilitated. That is, one of the memory traces for taste aversion remains as an increase in neurotransmitter released from the N3t cell. We thus conclude that the N3t cell suppresses the N1M cell in the feeding CPG, in response to the conditioned stimulus in Lymnaea CTA.

  2. DIFFERENTIAL TRACER COUPLING BETWEEN PAIRS OF IDENTIFIED NEURONES OF THE MOLLUSC LYMNAEA STAGNALIS

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    Ewadinger; Syed; Lukowiak; Bulloch

    1994-07-01

    Electrical coupling is a common means of cell-to-cell communication in both neuronal and non-neuronal tissues (Lowenstein, 1985). Within the nervous system, many electrically coupled neurones exhibit dye coupling (Bennett, 1973; Stewart, 1978; Glantz and Kirk, 1980; Spencer and Satterlie, 1980; Fraser and Heitler, 1993); however, some electrically coupled cells do not dye-couple (Audesirk et al. 1982; Murphy et al. 1983; Berdan, 1987; Robinson et al. 1993; Veenstra et al. 1993). Electrical coupling and dye coupling, often considered in parallel, are in fact two different parameters that can vary independently (e.g. Audesirk et al. 1982; Perez-Armendariz et al. 1991). The giant identified neurones of pulmonate and opisthobranch molluscs have frequently been used for studies of neuronal communication and its plasticity (Winlow and McCrohan, 1987; Bulloch, 1989). In the present study, we explored the relationship between electrical and tracer coupling in both strongly and weakly coupled pairs of molluscan neurones. Specifically, we examined electrically coupled, identified neurones in a freshwater pond snail, Lymnaea stagnalis L., and tested for tracer coupling with Lucifer Yellow CH and biocytin. The cells examined were the strongly electrically coupled neurones, visceral dorsal 1 (VD1) and right parietal dorsal 2 (RPD2) (Boer et al. 1979; Benjamin and Pilkington, 1986), and the weakly coupled neurones, left buccal 1 (LB1) and right buccal 1 (RB1) (Benjamin and Rose, 1979). The use of these particular neurones made it possible to compare electrical coupling with tracer coupling in the molluscan central nervous system (CNS). All experiments were performed on laboratory-bred Lymnaea stagnalis (Mollusca, Pulmonata), maintained as previously described (Ridgway et al. 1991). The CNS was dissected from mature animals (16­18 mm shell length) and pinned to the silicone rubber (RTV 616 GE) base of a recording dish in normal saline (51.3 mmol l-1 NaCl, 1.7 mmol l-1 KCl, 4

  3. Relação entre a patogenicidade do Schistosoma mansoni em camundongos e a susceptibilidade do molusco vetor: III. Mortalidade, pesos corporal e das vísceras

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    Zanotti-Magalhães Eliana Maria

    1995-01-01

    Full Text Available Estudou-se a relação entre o desenvolvimento da hepatomegalia, da esplenomegalia, peso corporal e taxa de mortalidade em camundongos experimentalmente infectados por Schistosoma mansoni com o grau de susceptibilidade de Biomphalaria glahrata e B. tenagophila nas quais se desenvolveram as cercárias infectantes respectivamente, das linhagens BH e SJ. Foram utilizados como hospedeiro definitivo camundongos Swiss, SPF e como hospedeiros intermediários populações de moluscos selecionados geneticamente para o caráter susceptibilidade. Foram observados menores pesos corporais e das visceras em camundongos infectados com cercárias provenientes de moluscos que apresentaram elevado grau de susceptibilidade. A maior susceptibilidade dos moluscos à infecção pelo S. mansoni correspondeu a uma menor sobrevivência dos camundongos infectados. Os resultados fazem crer que a maior adaptação do parasita ao hospedeiro intermediário, traduzidos pelas taxas mais elevadas de susceptibilidade, pode levar a um comportamento diferente deste parasita no hospedeiro definitivo.

  4. Dynamic of population-dynamics in a medically important snail species Lymnaea (Radix Luteola (Lamarck

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    T. K. Misra

    1993-09-01

    Full Text Available The life-cycle parameters of the snail Lymnaea (Radix luteola and the factors influencing the same have been studied under laboratory conditions. Ins each month, from July 1990 to June 1991, a batch of 100 zero-day old individual were considered for studies. The snails of April batch survived for 19.42 days while those in December batch survived for 87.45 days. The May batch individual though survived for 65.67 days gained maximum shell size (15.84 mm in length and body weight (419.87 mg. All individuals of April batch died prior to attainment of sexual maturity. In the remaining 11 batches the snails became sexually mature between 32 and 53 days. At this stage, they were with varying shell lengths, 9.3 mm to 13,11 mm in respect to batches. The reproduction period varied from 1-67 days. An individual laid, on an average, 0,25 (March batch to 443.67 (May batch eggs in its life-span. A batch of such snails would leave 24312, 22520, 720268, 80408, 76067, 418165, 214, 9202, 0, 0, 2459386 and 127894 individuals at the end of 352nd day. Since the environmental conditions were almost similar the 'dynamic' of population dynamics seems to be involved with the 'strain' of the snail individuals of the batches concerned.

  5. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

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    Tomoyo Takahashi

    Full Text Available The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose, with an unconditional stimulus (US, a tactile stimulation to the animal's head, over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min. It was critical that the cold-block be applied within 10 min to block long-term memory (LTM formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  6. Investigating apical adverse effects of four endocrine active substances in the freshwater gastropod Lymnaea stagnalis.

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    Giusti, Arnaud; Lagadic, Laurent; Barsi, Alpar; Thomé, Jean-Pierre; Joaquim-Justo, Célia; Ducrot, Virginie

    2014-09-15

    The hermaphroditic gastropod Lymnaea stagnalis is proposed as a candidate species for the development of OECD guidelines for testing of the reprotoxicity of chemicals, including endocrine active substances (EASs). Up to now, only a few putative EASs have been tested for their reproductive toxicity in this species. In this study, we investigate the effects of four EASs with different affinities to the vertebrate estrogen and androgen receptors (chlordecone as an estrogen; cyproterone acetate, fenitrothion and vinclozolin as anti-androgens) on the reproduction of L. stagnalis in a 21-day semi-static test. Testosterone and 17α-ethinylestradiol (EE2) were used as the reference compounds. The tested EASs had no significant effect on growth and survival at the tested concentration ranges (ng to μg/L). Classical reproduction endpoints (i.e., oviposition and fecundity) were not responsive to the tested chemicals, except for chlordecone and 17α-ethinylestradiol, which hampered reproduction from 19.6 μg/L and 17.6 μg/L, respectively. The frequency of polyembryonic eggs, used as an additional endpoint, demonstrated the effects of all compounds except EE2. The molecular pathways, which are involved in such reproduction impairments, remain unknown. Our results suggest that egg quality is a more sensitive endpoint as compared to other reproductive endpoints commonly assessed in mollusk toxicity tests.

  7. Environmental versus anthropogenic effects on population adaptive divergence in the freshwater snail Lymnaea stagnalis.

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    Anthony Bouétard

    Full Text Available Repeated pesticide contaminations of lentic freshwater systems located within agricultural landscapes may affect population evolution in non-target organisms, especially in species with a fully aquatic life cycle and low dispersal ability. The issue of evolutionary impact of pollutants is therefore conceptually important for ecotoxicologists. The impact of historical exposure to pesticides on genetic divergence was investigated in the freshwater gastropod Lymnaea stagnalis, using a set of 14 populations from contrasted environments in terms of pesticide and other anthropogenic pressures. The hypothesis of population adaptive divergence was tested on 11 life-history traits, using Q(ST-F(ST comparisons. Despite strong neutral differentiation (mean F(ST = 0.291, five adult traits or parameters were found to be under divergent selection. Conversely, two early expressed traits showed a pattern consistent with uniform selection or trait canalization, and four adult traits appeared to evolve neutrally. Divergent selection patterns were mostly consistent with a habitat effect, opposing pond to ditch and channel populations. Comparatively, pesticide and other human pressures had little correspondence with evolutionary patterns, despite hatching rate impairment associated with global anthropogenic pressure. Globally, analyses revealed high genetic variation both at neutral markers and fitness-related traits in a species used as model in ecotoxicology, providing empirical support for the need to account for genetic and evolutionary components of population response in ecological risk assessment.

  8. Bait Formulations of Chlorophyllin against Infected/Uninfected Lymnaea acuminata in Red and Sunlight

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    Navneet Kumar

    2015-01-01

    Full Text Available Control of snail population is an important tool in fasciolosis control programme. In order to achive this objective the method of bait formulation containing an attractant and a molluscicide is an appropriate approach to ensure the death of host snail. Chlorophyllin bait pellets were prepared by addition of attractants starch (10 mM/serine (20 mM and Chlorophyllin 2% agar solution. These baits were used against host snail Lymnaea acuminata. The behavioral response of snail against attractant (starch/serine and chlorophyllin was examined in red and sunlight. The fraction of snail that was in contact with chlorophyllin bait in zone-3 was used as measure of attraction process. Infected snails were more attracted with red light+starch (57.7%. Uninfected snails were more attracted by red light+serine (58.0%. The molluscicidal activity of chlorophyllin against infected snails in red light (96h LC50-1.88% chlorophyllin in bait and sunlight (96h LC50-2.40% chlorophyllin in bait was more pronounced than uninfected snail in red light (96h LC50-1.76% Chlorophyllin in bait and sunlight (96h LC50-3.62% chlorophyllin in bait.

  9. Lymnaea glabra: progressive increase in susceptibility to Fasciola hepatica through successive generations of experimentally infected snails.

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    Rondelaud, D; Teukeng, F F Djuikwo; Vignoles, P; Dreyfuss, G

    2015-07-01

    Experimental infections of Lymnaea glabra (two populations) with Fasciola hepatica were carried out during seven successive snail generations, to determine if prevalence and intensity of snail infection increased over time through descendants of snails already infected with F. hepatica. Controls were descendants coming from uninfected parents and infected according to the same protocol. No larval forms were found in the bodies of control snails coming from uninfected parents. In contrast, prevalence and intensity of F. hepatica infection in snails originating from infected parents progressively increased from the F2 or F3 to the F6 generation of L. glabra. In another experiment carried out with the F7 generations of L. glabra and a single generation of Galba truncatula (as controls), the prevalence of F. hepatica infection and the total number of cercariae were lower in L. glabra (without significant differences between both populations). If the number of cercariae shed by infected snails was compared to overall cercarial production noted in snails containing cercariae but dying without emission, the percentage was greater in G. truncatula (69% instead of 52-54% in L. glabra). Even if most characteristics of F. hepatica infection were lower in L. glabra, prevalence and intensity of parasite infection increased with snail generation when tested snails came from infected parents. This mode of snail infection with F. hepatica suggests an explanation for cases of fasciolosis occurring in cattle-breeding farms where paramphistomosis is lacking and G. truncatula is absent.

  10. Rearing of Lymnaea columella (Say, 1817, intermediate host of Fasciola hepatica (Linnaeus, 1758

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    Souza Cecília Pereira de

    2000-01-01

    Full Text Available The intermediate host of Fasciola hepatica, Lymnaea columella, collected in Belo Horizonte, Minas Gerais, Brazil, was reared in our laboratory. The aim of the current study was to standardize a rearing and maintenance technique. Two kinds of diet were tested: fresh lettuce (A and rodent ration + 10% CaCO3 plus fresh lettuce (B. The age for the beginning of oviposition ranged from 27 to 57 days. Ten days after oviposition at 24.7°C, 100% eclosion occurred. The complete life cycle varied from 37 to 67 days. The average numbers of eggs per egg mass were 26.3 and 31.1 with diets (A and (B, respectively. The lettuce and ration fed snails presented a increased growth although the difference was not statistically significant (p > 0.05. The mortality rate varied from 40 to 64% after 90 days. The maximum longevity was 183 days, 21.5 mm length and 11 mm wide. The methodology to mass breed and maintain these snails was found to be suitable in the laboratory

  11. Comparative toxicity of Paraquat herbicide and some plant extracts in Lymnaea natalensis snails.

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    Bakry, Fayez A; Eleiwa, Mona E; Taha, Samir A; Ismil, Somya M

    2016-01-01

    Paraquat has been shown to be a highly toxic compound for humans and animals, and many cases of acute poisoning and death have been reported over the past few decades. The present study was undertaken to evaluate comprehensively herbicides (Paraquat) and some plant extracts to biochemical aspects of Lymnaea natalensis snails. It was found that the exposure of L. natalensis to Paraquat and plant extracts led to a significant reduction in the infectivity of Fasciola gigantica miracidia to the snail. The glucose level in hemolymph of exposed snails was elevated, while the glycogen showed a decrease in soft tissues when compared with the control group. In addition, the activity level of some enzymes representing glycolytic enzymes as hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK), lactate dehydrogenase (LDH), and glucose phosphate isomerase (GPI) in snail's tissues were reduced in response to the treatment. It was concluded that the pollution of the aquatic environment by herbicide would adversely affect the metabolism of the L. natalensis snails. Snails treated with Agave attenuate, Ammi visnaga, and Canna iridiflora plant had less toxic effect compared to snails treated with Paraquat.

  12. Influence of photon beam irradiation on Lymnaea natalensis snails infected with Fasciola gigantica.

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    Said, Doaa E; Rostom, Yousry A

    2006-04-01

    Lymnaea natalensis is the intermediate host of Fasciola gigantica in Egypt. The effect of photon beam irradiation on the ability of the laboratory reared L. natalensis to support the larval development of F. gigantica has been studied. 120 snails were divided into two groups: The control infected non irradiated group (GI) and the experimental infected irradiated group (GII). The later group was subdivided into two subgroups: GIIa: snails irradiated before infection and GIIb: snails irradiated after infection. Photon beam irradiation had non significant effect on the survival rate between the all groups at the 30th day post infection. The life span, the number of infected snails and the length of the shedding period were significantly decreased in the two irradiated subgroups than the control group. The effect was more obvious on GIIb without significant difference. The number of metacercariae significantly decreased in the 2 irradiated subgroups than the control one. Also, it was significantly decreased in GIIb when compared with GIIa. So, photon beam irradiation has a great role on retarding larval development of F. gigantica inside the snail. This opens the way to a new strategy for fascioliasis control of in Egypt.

  13. Fasciola gigantica: larval productivity of three different miracidial isolates in the snail Lymnaea truncatula.

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    Dar, Y; Vignoles, P; Rondelaud, D; Dreyfuss, G

    2003-03-01

    Bimiracidial infections of Lymnaea truncatula with three isolates of Fasciola gigantica, originating from China, Egypt and Madagascar, were carried out to determine the effect of geographic origin of the parasite on the larval productivity of redial generations. The prevalences of experimental infections in snails exposed to strains from Madagascar, China and Egypt were 20.8%, 60.0% and 80.0%, respectively. At day 49 post-exposure (p.e.), the total number of free rediae in snails infected with the Egyptian isolate was significantly higher than that recorded in the Madagascan group. On the other hand, at day 49 p.e., the majority of cercariae in the Chinese and Egyptian groups were produced by R2a rediae (70.6% and 66.6% of cercariae produced by all live rediae), while, in the Madagascan group, the cercariae were produced mainly by the first redial generation. Snails infected with the Egyptian isolate of miracidia developed more live rediae and, consequently, could produce a higher number of cercariae. As a result, L. truncatula snails were highly adapted to infections with the Egyptian and Chinese isolates of F. gigantica.

  14. Effects of Fasciola gigantica experimental infection on some inorganic elements in the snail host Lymnaea natalensis.

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    Mostafa, Osama Mohammad Sayed

    2008-04-01

    Flame atomic absorption spectrometry was performed to determine the alteration in the concentrations of metallic ion Pb, Zn, K, Na, Fe, Cu and Co in the soft parts of the Lymnaea natalensis snails shedding Fasciola gigantica cercariae and to determine the alteration in the concentration of Ca in the soft parts and shells of the same snails. The Co was found to be present at concentration level below the detection limits of the analytical method used. Regarding detected elements, three elements Zn, K and Cu were found to be present at significantly higher concentrations in cercariae-shedding snails compared with uninfected snails. Two elements, Pb and Na, showed significant decrease in cercariae-shedding snails compared to uninfected ones. The concentration of Fe showed non-significant increase. The results showed significant lowering in the calcium content of the shells and soft parts of cercariae-shedding snails relative to the calcium content in the uninfected ones. The obtained results and the hypothesis of hypercalcification in shells of infected snails were discussed.

  15. Rearing of Lymnaea columella (Say, 1817), intermediate host of Fasciola hepatica (Linnaeus, 1758).

    Science.gov (United States)

    Pereira de Souza, C; Magalhães, K G

    2000-01-01

    The intermediate host of Fasciola hepatica, Lymnaea columella, collected in Belo Horizonte, Minas Gerais, Brazil, was reared in our laboratory. The aim of the current study was to standardize a rearing and maintenance technique. Two kinds of diet were tested: fresh lettuce (A) and rodent ration + 10% CaCO3 plus fresh lettuce (B). The age for the beginning of oviposition ranged from 27 to 57 days. Ten days after oviposition at 24.7 degrees C, 100% eclosion occurred. The complete life cycle varied from 37 to 67 days. The average numbers of eggs per egg mass were 26.3 and 31.1 with diets (A) and (B), respectively. The lettuce and ration fed snails presented a increased growth although the difference was not statistically significant (p > 0.05). The mortality rate varied from 40 to 64% after 90 days. The maximum longevity was 183 days, 21.5 mm length and 11 mm wide. The methodology to mass breed and maintain these snails was found to be suitable in the laboratory

  16. Cercarial productivity of Fasciola hepatica in Lymnaea truncatula during usual and unusual development of redial generations.

    Science.gov (United States)

    Augot, D; Rondelaud, D

    2001-08-01

    Single-miracidium infections of Lymnaea truncatula by Fasciola hepatica were carried out to determine the cercarial productivity of each redial generation when the first-appearing mother redia (R1a redia) normally developed (usual development of redial generations) or quickly died (unusual development). In both developmental patterns of infection, the number of morulae was significantly higher in the second-appearing mother rediae (R1b group) than in either the daughter rediae from R1a rediae (R2a group) or the rediae from subsequent groups (R2b/R3a). The live R1a group did not produce cercariae. The percentages of cercariae produced by the R1b, R2a, and R2b/R3a groups were 28.2%, 62.8%, and 8.9% when the development of redial generations was usual. In contrast, in an unusual development, they were 69.3%, 20.3%, and 10.2%, respectively. Cercarial production until day 63 post-exposure was essentially provided by the R2a rediae, when the development of redial generations was usual, and by the R1b rediae when it was unusual.

  17. Population dinamics of Lymnaea rubiginosa in rice fields and its infection with larvae of trematodes

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    Suhardono

    2000-12-01

    Full Text Available Field of irrigated rice paddy was the most suitable habitat as breeding site of snail Lymnaea rubiginosa, the intermadiate host of Fasciola gigantica and other trematodes. Fluctuations in the population of fresh water snail, L. rubiginosa in irrigated rice fields and their infection with L. rubiginosa and other trematodes were studied in five villages in the subdistrict of Surade, provivine of West Java. Snail were sampled based on time collection (half man hour each site of collection. The samples of the snails were further counted and examined for the presence of larval trematodes. The result indicated that snails died during the dry season except those in persistent aquatic refuges such as streams and springs. Surviving snails recolonised rice fields near villages by passive transfer with water from refuges early in the wet season. Some recolonosation may also have resulted from haching of snail eggs deposited in habitats which had not been dried for more than a few weeks. Recolonisation with snails of further rice fields from a village occurred during the later period of the wet season. No snail infected with F. gigantica was found in the distance of more than 200 m from a village. Snail with the highest prevalence of infection occurred in rice fields which received effluent from a cattle pen were fertilised with bovine faeces. Each snail was only infected with one species of tramatodes. Infection with echinostone larvae was most common.

  18. Larval trematode infections in Lymnaea glabra populations living in the Brenne Regional Natural Park, central France.

    Science.gov (United States)

    Rondelaud, Daniel; Vignoles, Philippe; Dreyfuss, Gilles

    2015-01-01

    Lymnaea glabra is known to be a natural intermediate host of two flukes, Calicophoron daubneyi and Fasciola hepatica, in central France. But it can also sustain larval development of other digeneans. Adult snails were thus collected from 206 habitats in 2014 and 2015 to identify parasite species and determine the prevalence of each digenean infection in relation to the five types of snail habitats. Seven digenean species were noted in 321 infected snails (out of 17,647 L. glabra). Snails with F. hepatica or C. daubneyi were found in 14.5% and 12.6% of habitats, respectively. Percentages were lower for snails with Opisthoglyphe ranae (5.8%), Haplometra cylindracea (5.3%) and were less than 5% for those infected with Echinostoma revolutum, Notocotylus sp. or Plagiorchis sp. Prevalence noted for each parasite species varied with the type of habitat. The number of species in L. glabra was lower than that found in G. truncatula from the same region (7 instead of 10). The distribution and prevalence of each digenean species were thus dependent on the type and location of each snail habitat. © D. Rondelaud et al., published by EDP Sciences, 2015.

  19. Estrogen-related fecundity reduction of Lymnaea ollula following Fasciola gigantica infection.

    Science.gov (United States)

    Kumkate, Supeecha; Onmek, Nuttajit; Boonburapong, Bongkoj; Singhakaew, Sombut; Leardkamolkarn, Vijittra

    2009-12-01

    Infection by trematode parasites generally affects life history traits of their intermediate hosts. Reduction in life expectancy and reproductive capacity have previously been documented in Fasciola gigantica-infected Lymnaea ollula, but the influence of the endocrine system on this specific host–parasite interaction has not been previously examined. In the present study, we observed survival, growth pattern, and reproductive output of L. ollula following exposure to F. gigantica. Both the survival and the growth pattern of infected snails were similar to those of the non-infected control group. However, a significant difference was apparent in fecundity, as infected snails consistently showed lower levels of egg and embryo production throughout a 7-wk observation period. Semi-quantitative RT-PCR also revealed down-regulation of estrogen receptor expression in infected snails during the first 4 wk of infection. Nonetheless, the inhibition of estrogen signaling was transient, as they regained expression in the later phase of infection. It is, therefore, suggested that other hormones of the complex endocrine system may be involved in the reduced fecundity of L. ollula following F. gigantica infection.

  20. More efficient allopatric combinations of Fasciola hepatica and Lymnaea truncatula due to modification of redial development?

    Science.gov (United States)

    Goumghar, M D; Dreyfuss, G; Rondelaud, D; Benlemlih, M; Cabaret, J

    2001-12-01

    Experimental infections of two susceptible French populations of Lymnaea truncatula (Courcelles and Saint Ours) with an allopatric (Fès, Morocco) or a semi-sympatric (Limoges, France) isolate of Fasciola hepatica miracidia were performed to determine the effect of allopatric miracidia on redial and cercarial production. In both populations, cercarial release was significantly greater in allopatric than in semi-sympatric snails. Compared to semi-sympatric snails, the examination of allopatric snails killed from day 14 to day 35 post-exposure demonstrated (1) a significant decrease after day 28 in the number of daughter rediae (R2a group) exiting from the first-appearing mother redia (R1a redia), and (2) the differentiation of numerous daughter rediae (R2b group) in the body of second-appearing mother rediae (R1b group). These experiments demonstrated that the exposure of L. truncatula to an allopatric isolate of miracidia disturbed the usual developmental pattern of redial generations and caused the formation of numerous R2b rediae. The authors hypothesized that the increase in cercarial release noted in allopatric snails would be assured by the rediae from the R2b group after their emergence from the body of R1b mother rediae.

  1. Larval development of Fasciola hepatica in experimental infections: variations with populations of Lymnaea truncatula.

    Science.gov (United States)

    Vignoles, P; Dreyfuss, G; Rondelaud, D

    2002-06-01

    A retrospective study was undertaken on 70 French populations of Lymnaea truncatula experimentally infected with Fasciola hepatica to determine whether or not susceptibility of snails to infection influenced redial and cercarial production. Results were compared with those obtained from two control populations, known for prevalences higher than 60% when experimentally infected with F. hepatica. In the 70 other populations examined, the prevalences ranged from 2 to 75%. In 55 of these populations, where the prevalence was more than 20%, a high proportion (50.1-56.8%) of snails died after cercarial shedding, whereas in the other groups (non-shedding snails with the most differentiated larvae being free cercariae, rediae containing cercariae, immature rediae, or sporocysts, respectively), snail death was significantly less. In 11 populations, where the prevalence values were 5-19%, only 14% of snails died after cercarial shedding, whereas snails with free cercariae, rediae with cercariae, or immature rediae showed significant increases in snail mortality. In the remaining four snail populations, with prevalences of less than 5%, the most differentiated larval forms were only immature rediae and/or sporocysts. Overall, the number of rediae containing cercariae significantly decreased with decreasing prevalence values. The low prevalence of experimental infection in several populations of snails might be explained by the occurrence of natural infections with miracidia originating from a mammalian host other than cattle, and/or by genetic variability in the susceptibility of snails to infection.

  2. Development of Fasciola hepatica in Lymnaea columella infected with miracidia derived from cattle and marmoset infections.

    Science.gov (United States)

    Mendes, E A; Lima, W S; de Melo, A L

    2008-03-01

    The development of Fasciola hepatica from two species of definitive hosts, i.e. cattle (Bos taurus) and a marmoset (Callithrix penicillata) in the snail Lymnaea columella was determined based on the production of rediae and cercariae and snail survival rate. More rediae and cercariae at 60-74 days post-infection were produced by snails infected by cattle-derived miracidia (cattle group) than by those infected by marmoset-derived miracidia (marmoset group). Among the L. columella parasitized by the marmoset group, the survival rate and the percentage of positive snails were higher than among those parasitized by the cattle group. Eggs of F. hepatica released in cattle faeces were significantly bigger than those released in marmoset faeces. Miracidia originating from parasites that completed their development in cattle were more efficient in infecting the intermediate host. These results suggest that vertebrate-host origin influences the eggs produced by the parasite and the infection rates in the snail host L. columella.

  3. Reproductive impacts of tributyltin (TBT) and triphenyltin (TPT) in the hermaphroditic freshwater gastropod Lymnaea stagnalis.

    Science.gov (United States)

    Giusti, Arnaud; Barsi, Alpar; Dugué, Maël; Collinet, Marc; Thomé, Jean-Pierre; Joaquim-Justo, Célia; Roig, Benoit; Lagadic, Laurent; Ducrot, Virginie

    2013-07-01

    Tributyltin (TBT) and triphenyltin (TPT) are emblematic endocrine disruptors, which have been mostly studied in gonochoric prosobranchs. Although both compounds can simultaneously occur in the environment, they have mainly been tested separately for their effects on snail reproduction. Because large discrepancies in experimental conditions occurred in these tests, the present study aimed to compare the relative toxicity of TBT and TPT under similar laboratory conditions in the range of 0 ng Sn/L to 600 ng Sn/L. Tests were performed on the simultaneous hermaphrodite Lymnaea stagnalis, a freshwater snail in which effects of TPT were unknown. Survival, shell length, and reproduction were monitored in a 21-d semistatic test. Frequency of abnormal eggs was assessed as an additional endpoint. Triphenyltin hampered survival while TBT did not. Major effects on shell solidity and reproduction were observed for both compounds, reproductive outputs being more severely hampered by TBT than by TPT. Considering the frequency of abnormal eggs allowed increasing test sensitivity, because snail responses to TBT could be detected at concentrations as low as 19 ng Sn/L. However, the putative mode of action of the 2 compounds could not be deduced from the structure of the molecules or from the response of apical endpoints. Sensitivity of L. stagnalis to TBT and TPT was compared with the sensitivity of prosobranch mollusks with different habitats and different reproductive strategies.

  4. Peripheral sensory cells in the cephalic sensory organs of Lymnaea stagnalis.

    Science.gov (United States)

    Wyeth, Russell C; Croll, Roger P

    2011-07-01

    The peripheral nervous system in gastropods plays a key role in the neural control of behaviors, but is poorly studied in comparison with the central nervous system. Peripheral sensory neurons, although known to be widespread, have been studied in a patchwork fashion across several species, with no comprehensive treatment in any one species. We attempted to remedy this limitation by cataloging peripheral sensory cells in the cephalic sensory organs of Lymnaea stagnalis employing backfills, vital stains, histochemistry, and immunohistochemistry. By using at least two independent methods to corroborate observations, we mapped four different cell types. We have found two different populations of bipolar sensory cells that appear to contain catecholamines(s) and histamine, respectively. Each cell had a peripheral soma, an epithelial process bearing cilia, and a second process projecting to the central nervous system. We also found evidence for two populations of nitric oxide-producing sensory cells, one bipolar, probably projecting centrally, and the second unipolar, with only a single epithelial process and no axon. The various cell types are presumably either mechanosensory or chemosensory, but the complexity of their distributions does not allow formation of hypotheses regarding modality. In addition, our observations indicate that yet more peripheral sensory cell types are present in the cephalic sensory organs of L. stagnalis. These results are an important step toward linking sensory cell morphology to modality. Moreover, our observations emphasize the size of the peripheral nervous system in gastropods, and we suggest that greater emphasis be placed on understanding its role in gastropod neuroethology.

  5. Strain-specific differences of the effects of stress on memory in Lymnaea.

    Science.gov (United States)

    Hughes, Emily; Shymansky, Tamila; Swinton, Erin; Lukowiak, Kai S; Swinton, Cayley; Sunada, Hiroshi; Protheroe, Amy; Phillips, Iain; Lukowiak, Ken

    2017-03-01

    Stress alters the ability to form, recall and maintain memory according to the Yerkes-Dodson/Hebb (YDH) law. The effects of environmentally relevant stressors, such as low environmental calcium and crowding, on learning and memory have previously been described in a laboratory-reared 'average' strain of Lymnaea stagnalis (i.e. the Dutch strain) as well as two strains of freshly collected L. stagnalis with enhanced memory formation abilities (i.e. 'smart' snails). Here, we use L. stagnalis to study the effects of other environmentally relevant stressors on memory formation in two other strains of freshly collected snails, one 'smart' and one 'average'. The stressors we examined are thermal, resource restriction combined with food odour, predator detection and, for the first time, tissue injury (shell damage). We show that the same stressor has significantly different effects on memory formation depending on whether snails are 'smart' or 'average'. Specifically, our data suggest that a stressor or a combination of stressors act to enhance memory in 'average' snails but obstruct memory formation in 'smart' snails. These results are consistent with the YDH law and our hypothesis that 'smart' snails are more easily stressed than 'average' snails. © 2017. Published by The Company of Biologists Ltd.

  6. Associative learning and memory in Lymnaea stagnalis: how well do they remember?

    Science.gov (United States)

    Lukowiak, Ken; Sangha, Susan; McComb, Chloe; Varshney, Nishi; Rosenegger, David; Sadamoto, Hisayo; Scheibenstock, Andi

    2003-07-01

    The search for 'the how and the where' of memory formation in the brain, the engram, is still one of the unattained 'Holy Grails' of neuroscience. Over the years, various paths have been trodden in attempts to attain this goal, and while tantalizing glimpses appear now and then on the scientific horizon, the Grail still has not been grasped. One of the paths that investigators have walked is the invertebrate 'model system' approach. Some invertebrates possess relatively simple nervous systems that mediate relatively simple behaviours that are both interesting and trainable. In this commentary, we would like to shed light on a relatively new player, the pond snail Lymnaea stagnalis L., that is being used in the quest to illuminate 'the how and the where' the nervous systems encode and store memory. We will show that it is possible to demonstrate that a single neuron is a site of memory formation and storage for a form of associative learning in this lowly snail. It may be that the Grail is a little closer to being grasped.

  7. Molluscicidal activity of Sapindus mukorossi and Terminalia chebula against the freshwater snail Lymnaea acuminata.

    Science.gov (United States)

    Upadhyay, Aparna; Singh, D K

    2011-04-01

    The molluscicidal activity of Sapindus mukorossi and Terminalia chebula fruit powder against the vector snail Lymnaea acuminata was time and concentration dependent. The molluscicidal activity of T. chebula fruit powder (96 h LC(50):93.59 mg L(-1)) was more pronounced than that of S. mukorossi fruit powder (96 h LC(50):119.57 mg L(-1)). Ethanolic extracts of S. mukorossi and T. chebula fruit powder were more toxic than their other organic solvent extracts. The molluscicidal activity of ethanolic extract of S. mukorossi fruit powder (24h LC(50):2.75 mg L(-1)) was more effective than the ethanolic extract of T. chebula fruit powder (24h LC(50):124.06 mg L(-1)). The 96 h LC(50) of column-purified fraction of S. mukorossi fruit powder was 5.43 mg L(-1) whereas those of T. chebula fruit powder was 7.49 mg L(-1). Column, thin layer and high performance liquid chromatography analysis demonstrates that the active molluscicidal component in S. mukorossi and T. chebula is saponin (96 h LC(50):1.31 mg L(-1)) and tannic acid (96 h LC(50):1.64 mg L(-1)), respectively. These plants may be used as potent source of molluscicides against the snail L. acuminata.

  8. Larval trematode infections in Lymnaea glabra populations living in the Brenne Regional Natural Park, central France

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    Rondelaud Daniel

    2015-01-01

    Full Text Available Lymnaea glabra is known to be a natural intermediate host of two flukes, Calicophoron daubneyi and Fasciola hepatica, in central France. But it can also sustain larval development of other digeneans. Adult snails were thus collected from 206 habitats in 2014 and 2015 to identify parasite species and determine the prevalence of each digenean infection in relation to the five types of snail habitats. Seven digenean species were noted in 321 infected snails (out of 17,647 L. glabra. Snails with F. hepatica or C. daubneyi were found in 14.5% and 12.6% of habitats, respectively. Percentages were lower for snails with Opisthoglyphe ranae (5.8%, Haplometra cylindracea (5.3% and were less than 5% for those infected with Echinostoma revolutum, Notocotylus sp. or Plagiorchis sp. Prevalence noted for each parasite species varied with the type of habitat. The number of species in L. glabra was lower than that found in G. truncatula from the same region (7 instead of 10. The distribution and prevalence of each digenean species were thus dependent on the type and location of each snail habitat.

  9. The effect of artificial dehydration on the survival and reproduction of Lymnaea rubiginosa

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    S Widjajanti

    1999-03-01

    Full Text Available The effect of artificial dehydration on snail Lymnaea rubiginosa was investigated in the laboratory by monitoring its survival and development, because as aquatic organism, this snail must be able to adapt or tolerate with the changes in its habitat. Fifty laboratory-reared L. rubiginosa with shell length between 1.0-1.5 cm (adult were placed in each sloping earth aquarium (60x80x20 cm which were already filled with water about 15 cm depth. Five aquaria were used in this study, and one week after being established the water from 4 aquaria was drained while one aquarium was retained with water as a control. The water was replaced in one of dehydrated aquarium each week for four weeks, commencing one week after draining the water. The survival of snails in each aquarium were recorded every two days over a period of 3 months. The results indicated that the mortality rate of adult snails increased as the period of dehydration increased. After four week dehydration only 16% of adult snails survive compared to 68% survival in the control aquarium, and dehydration for 4 weeks prolonged the hatching time of eggs. Moreover, in dehydrated aquaria, the egg masses were deposited in a random pattern on the surface of the soil, whereas in the control aquarium they were laid on the soil-water junction.

  10. Moluscos asociados a las raíces sumergidas del mangle rojo Rhizophora mangle, en el Golfo de Santa Fe, Estado Sucre, Venezuela

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    B. Márquez

    2002-12-01

    Full Text Available Se realizó un estudio mensual cualitativo y cuantitativo de la comunidad de moluscos asociados a las raíces sumergidas del mangle rojo, Rhizophora mangle, entre octubre de 1998 y septiembre de 1999, en seis estaciones del Golfo de Santa Fe (Estado Sucre, Venezuela. Se colectaron e identificaron un total de 4 704 individuos pertenecientes a 45 especies de moluscos (22 gasterópodos, 15 bivalvos y 8 polyplacóforos. Las especies más abundantes fueron: Crassostrea rhizophorae, Isognomon bicolor L alatus y Brachidontes exustus. Los valores más altos de diversidad y equitabilidad, y los menores valores de dominancia, se encontraron en las estaciones tres y cuatro, mientras que lo opuesto ocurrió en las estaciones uno y dos. El análisis de afinidad mostró que en las cinco primeras estaciones las variaciones espaciales en la composición de la comunidad son mayores que las variaciones temporales, mientras que en la estación seis priman las diferencias temporales. Se encontraron factores que podrían ser importantes para determinar la estructura de la comunidad, como vecindad a otros ecosistemas y/6 aspectos biológicos específicos de las especies como adaptaciones a condiciones fluctuantes, hábitos alimenticios y migración en busca de ambientes sombreados y protegidos.A qualitative and quantitative monthly study of the mollusks community associated to the submered roots of the red mangrove, Rhizophora mangle (L., between October of 1998 and September of 1999, in six stations of the Gulf of Santa Fe. (Suere State, Venezuela. Were collected 4 704 specimens, 45 species of mollusks were identified (22 gastropods, 15 bivalves and 8 chitons. The most abundant species were: Crassostrea rhizophorae, Isognomon bicolor, L alatus and Brachidontes exustus. The highest values in diversity and evenness, and the smallest dominant values, were in the stations three and four, while the opposed happened in the stations one and two. The analysis of likeness

  11. Estado del conocimiento de la durofagia en el registro fósil: interacción depredador-presa en moluscos marinos (Clases Gastropoda y Bivalvia

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    Catalina Gómez-Espinosa

    2015-01-01

    Full Text Available La depredación como un mecanismo evolutivo, de diversificación y biomineralización es un tópico de gran interés. Un tipo específico de depredación es la durofagia que se define como el hábito alimenticio de los animales que consumen organismos con un esqueleto duro mineralizado, ya sea concha o exoesqueleto. Los moluscos representan una fuente muy importante para examinar la depredación durófaga en el registro fósil debido a su distribución mundial, abundancia, buena preservación y a que habitan en una gran variedad de ambientes. En este trabajo se revisa el número de artículos publicados en revistas de circulación internacional que se enfocan en el tema de la durofagia y que tienen como potenciales presas a gasterópodos y bivalvos marinos fósiles. Se recuperaron y revisaron 101 artículos sobre este tema, enfocados en seis tipos de evidencia: perforación, reparación y fragmentación de la concha, mordidas, “punctures” y coprolitos. La mayoría de los ejemplos correspondieron a moluscos del Cenozoico. En general hay más registros en la zona tropical. Durante el Paleozoico, la mayoría de las veces, no se identificó el potencial depredador; esta tendencia continuó en el Mesozoico pero se reconoció la depredación de gasterópodos y bivalvos por parte de gasterópodos carnívoros, artrópodos, peces y reptiles. Durante el Cenozoico dominó la depredación por parte de gasterópodos natícidos y murícidos y se reconoció también la depredación por parte de ar trópodos, peces y mamíferos.

  12. Menin: a tumor suppressor that mediates postsynaptic receptor expression and synaptogenesis between central neurons of Lymnaea stagnalis.

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    Nichole Flynn

    Full Text Available Neurotrophic factors (NTFs support neuronal survival, differentiation, and even synaptic plasticity both during development and throughout the life of an organism. However, their precise roles in central synapse formation remain unknown. Previously, we demonstrated that excitatory synapse formation in Lymnaea stagnalis requires a source of extrinsic NTFs and receptor tyrosine kinase (RTK activation. Here we show that NTFs such as Lymnaea epidermal growth factor (L-EGF act through RTKs to trigger a specific subset of intracellular signalling events in the postsynaptic neuron, which lead to the activation of the tumor suppressor menin, encoded by Lymnaea MEN1 (L-MEN1 and the expression of excitatory nicotinic acetylcholine receptors (nAChRs. We provide direct evidence that the activation of the MAPK/ERK cascade is required for the expression of nAChRs, and subsequent synapse formation between pairs of neurons in vitro. Furthermore, we show that L-menin activation is sufficient for the expression of postsynaptic excitatory nAChRs and subsequent synapse formation in media devoid of NTFs. By extending our findings in situ, we reveal the necessity of EGFRs in mediating synapse formation between a single transplanted neuron and its intact presynaptic partner. Moreover, deficits in excitatory synapse formation following EGFR knock-down can be rescued by injecting synthetic L-MEN1 mRNA in the intact central nervous system. Taken together, this study provides the first direct evidence that NTFs functioning via RTKs activate the MEN1 gene, which appears sufficient to regulate synapse formation between central neurons. Our study also offers a novel developmental role for menin beyond tumour suppression in adult humans.

  13. Menin: A Tumor Suppressor That Mediates Postsynaptic Receptor Expression and Synaptogenesis between Central Neurons of Lymnaea stagnalis

    Science.gov (United States)

    Flynn, Nichole; Getz, Angela; Visser, Frank; Janes, Tara A.; Syed, Naweed I.

    2014-01-01

    Neurotrophic factors (NTFs) support neuronal survival, differentiation, and even synaptic plasticity both during development and throughout the life of an organism. However, their precise roles in central synapse formation remain unknown. Previously, we demonstrated that excitatory synapse formation in Lymnaea stagnalis requires a source of extrinsic NTFs and receptor tyrosine kinase (RTK) activation. Here we show that NTFs such as Lymnaea epidermal growth factor (L-EGF) act through RTKs to trigger a specific subset of intracellular signalling events in the postsynaptic neuron, which lead to the activation of the tumor suppressor menin, encoded by Lymnaea MEN1 (L-MEN1) and the expression of excitatory nicotinic acetylcholine receptors (nAChRs). We provide direct evidence that the activation of the MAPK/ERK cascade is required for the expression of nAChRs, and subsequent synapse formation between pairs of neurons in vitro. Furthermore, we show that L-menin activation is sufficient for the expression of postsynaptic excitatory nAChRs and subsequent synapse formation in media devoid of NTFs. By extending our findings in situ, we reveal the necessity of EGFRs in mediating synapse formation between a single transplanted neuron and its intact presynaptic partner. Moreover, deficits in excitatory synapse formation following EGFR knock-down can be rescued by injecting synthetic L-MEN1 mRNA in the intact central nervous system. Taken together, this study provides the first direct evidence that NTFs functioning via RTKs activate the MEN1 gene, which appears sufficient to regulate synapse formation between central neurons. Our study also offers a novel developmental role for menin beyond tumour suppression in adult humans. PMID:25347295

  14. Ingestion of Fasciola gigantica metacercariae by the intermediate host snail, Lymnaea ollula, and infectivity of discharged metacercariae.

    Science.gov (United States)

    Yoshihara, Shinobu; Ueno, Hakaru

    2004-09-01

    The rate of ingestion of Fasciola normal metacercariae (NMc) encysted on plants by Lymnaea ollula was examined, and the infectivity of the ingested metacercariae (IMc) in the feces of the host snail to mice was studied. As a result of ingestion by snails, the metacercarial outer cyst disappeared in about 50% of IMc in feces. There was no significant difference in the liver juvenile recovery at autopsy between mice inoculated with NMc and IMc kinds of metacercariae. Compared with NMc, the number of IMc could more easily be counted, because the separation of IMc from fecal contents under a microscope was not laborious.

  15. Fasciola immature stages sought in Lymnaea species and Biomphalaria species in the water bodies of Dakahlia Governorate.

    Science.gov (United States)

    el-Shazly, Atef M; Helmy, Moshira M F; Haridy, Fouad M; el-Sharkawy, Eman M A; Morsy, Tosson A

    2002-04-01

    Examination of the five different water bodies in Dakahlia governorate, revealed four species of Lymnaea. These were L. natalensis (68.4%). L. truncatula (16%), L. stagnalis (12.2%) and L. columella (3.4%). Also, two species of Biomphalaria were recovered. These were B. alexandrina (54.7%) and B. glabrata (45.3%). Examination of all these snails showed natural infection with immature stages of Fasciola sp. in 5.5% of L. natalensis (= cailliaudi), 3.1% in L. truncatula and 0.67% in B. alexandrina. The importance of these snails in dissemination and spreading of fascioliasis was discussed.

  16. First report of Lymnaea columella Say, 1817 (Pulmonata: Lymnaeidae) naturally infected with Fasciola hepatica (Linnaeus,1758) (Trematoda: Digenea) in Argentina.

    Science.gov (United States)

    Prepelitchi, Lucila; Kleiman, Florencia; Pietrokovsky, Silvia M; Moriena, Ricardo A; Racioppi, Oscar; Alvarez, José; Wisnivesky-Colli, Cristina

    2003-10-01

    We report the first evidence of natural infection of Lymnaea columella with Fasciola hepatica in Argentina. A sample of 601 snails was collected in May 2003 in northeastern Corrientes, a province bounded on the north by Paraguay, on the east by Brazil and on the southeast by Uruguay. Among 500 examined snails, 44 (8.8%) were exclusively infected with F. hepatica. Parasite identification was based on morphological features of cercariae from snails, and of eggs and adult flukes from Wistar rats. We discuss the events suggesting that an enzootic transmission cycle of F. hepatica has been recently established in northeastern Corrientes.

  17. PKA-Dependent Regulation of Synaptic Enhancement between a Buccal Motor Neuron and Its Regulatory Interneuron in Lymnaea stagnalis

    OpenAIRE

    Nakamura, Hiroshi; Kobayashi, Suguru; Kojima, Satoshi; Urano, Akihisa; Ito, Etsuro

    1999-01-01

    The cerebral giant cell (CGC) is known to play a crucial role in the regulation of feeding response in the pond snail, Lymnaea stagnalis. However, the mechanisms of signal transduction from the CGC to the following buccal motor neurons are not clear. In the present study, we examined whether cyclic AMP (cAMP)-dependent protein kinase (PKA) contributes to enhancement of a monosynaptic connection between the presynaptic CGC and the postsynaptic buccal motor neuron 1 (B1 cell). Injection of cAMP...

  18. ESR dating of Lymnaea baltica and Cerastoderma glaucum from low Ancylus level and transgressive Litorina Sea deposits

    Energy Technology Data Exchange (ETDEWEB)

    Molodkov, Anatoly [AN Ehstonskoj SSR, Tallin (Estonia). Inst. Geologii

    1996-11-01

    Freshwater gastropod (Lymnaea baltica) and brackish-water bivalve (Cerastoderma glaucum) shell samples from Ancylus Lake and Litorina Sea deposits on Hiiuma Island (north-west Estonia) were subjected to ESR measurements. All L. baltica shells studied were composed of calcite and displayed typical multicomponent ESR spectra. C. Glaucum shells normally show ESR spectra typical of aragonite with five radiation-induced lines. In the present work a C. glaucum with calcite-like spectra was encountered for the first time. The problem connected with accumulated palaeodose determination in shell fossils with unusual ESR spectra is highlighted. (author).

  19. First report of Lymnaea columella Say, 1817 (Pulmonata: Lymnaeidae naturally infected with Fasciola hepatica (Linnaeus,1758 (Trematoda: Digenea in Argentina

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    Prepelitchi Lucila

    2003-01-01

    Full Text Available We report the first evidence of natural infection of Lymnaea columella with Fasciola hepatica in Argentina. A sample of 601 snails was collected in May 2003 in northeastern Corrientes, a province bounded on the north by Paraguay, on the east by Brazil and on the southeast by Uruguay. Among 500 examined snails, 44 (8.8% were exclusively infected with F. hepatica. Parasite identification was based on morphological features of cercariae from snails, and of eggs and adult flukes from Wistar rats. We discuss the events suggesting that an enzootic transmission cycle of F. hepatica has been recently established in northeastern Corrientes.

  20. Variability and frequent failure of lucifer yellow to pass between two electrically coupled neurons in Lymnaea stagnalis.

    Science.gov (United States)

    Audesirk, G; Audesirk, T; Bowsher, P

    1982-07-01

    The electrically coupled giant neurosecretory neurons VD1 and RPD2 of Lymnaea stagnalis were found to have coupling coefficients ranging from ca. 0.1-0.6. When the fluoroescent dye Lucifer Yellow was injected intracellularly into one of the neurons, in most preparations no dye was observed to pass through into the coupled cell body or the process leading to it. There was no apparent correlation between the amount of dye coupling and the length of time allowed for diffusion of the dye in the cells. In eight preparations, the electrical coupling coefficient was measured before dye was injected. There was no correlation between dye coupling and the electrical coupling coefficient.

  1. Ocorrência de infecção natural de Fasciola hepatica Linnaeus, 1758 em Lymnaea columella Say, 1817 no Vale do Paraíba, SP, Brasil

    OpenAIRE

    Marlene Tiduko Ueta

    1980-01-01

    Foram registradas em Piquete, no vale do rio Paraíba do Sul (SP), Brasil, taxas de 1,22% e 0,14% de infecção natural em Lymnaea columella, por Fasciola hepatica. Em um único exemplar de Lymnaea columella dentre os 1.052 examinados, foram observadas rédias com xifidiocercárias, rédias com cercárias de Fasciola hepatica e metacercárias de Echinostomatidae.Infection rates of 1.22% and 0.14% were obtained in Lymnaea columella snails naturally infected by Fasciola hepatica. Samples of the snails w...

  2. Lesões molusco-símiles em paciente com esporotricose Molluscum-like lesions in a patient with sporotrichosis

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    Regina Casz Schechtman

    2011-12-01

    Full Text Available Esporotricose é uma infecção fúngica subcutânea, adquirida por inoculação direta, causada pelo Sporothrix schenckii. Embora a apresentação clássica linfocutânea represente a maioria dos casos, as formas clínicas atípicas e graves têm aumentado em ocorrência. Esporotricose sistêmica e esporotricose cutânea disseminada são variantes raras, usualmente associadas à imunodeficiência celular ou a estados debilitantes. Relatamos o primeiro caso na literatura de lesões molusco-símiles em esporotricose cutaneomucosa múltipla. Os exames micológico direto e histopatológico apresentavam-se ricos em células leveduriformes.Sporotrichosis is a subcutaneous fungal infection caused by Sporothrix schenckii and acquired by direct inoculation. Although the majority of cases consist of the classic lymphocutaneous presentation, the frequency of atypical and severe clinical forms of the disease has increased progressively. Systemic and disseminated cutaneous sporotrichosis constitute rare variants and such cases are generally associated with cellular immunodeficiency or debilitated states. The present paper describes the first published case of molluscum-like lesions in disseminated mucocutaneous sporotrichosis. Direct mycological examination and histopathology revealed numerous yeast cells.

  3. Moluscos vectores da esquistossomose mansônica no lado leste do Rio São Francisco, no Estado da Bahia

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    Air Colombo Barretto

    1981-06-01

    Full Text Available Pela primeira vez foi realizado um levantamento malacológico de espécies vectoras de Schistosoma mansoni na região do lado Oeste do Rio São Francisco, no Estado da Bahia. Observou-se que nas áreas onde a única espécie encontrada foi B. straminea, a esquistossomose não constitui um problema médico. Entretanto, nas áreas onde foi coletado B. glabraata, além de B. straminea, a esquistossomose se apresenta com características de alta endemicidade. A ausência de moluscos, apesar da abundância de água, foi observada em extensas áreas, quase despovoadas. Esse quadro poderá se modificar em futuro bem próximo, devido â construção de novas estradas, bem como pela implantação de projetos de irrigação. Baseados nos presentes resultados e, em dados da literatura, os autores correlacionam a distribuição geográfica das espécies vectoras com a endemicidade da esquistossomose no Brasil.

  4. Moluscos gasterópodos terrestres como indicadores de recuperación de bosque en los paisajes del Sur y Norcentro de Nicaragua

    Directory of Open Access Journals (Sweden)

    Marlon Sotelo

    2015-10-01

    Full Text Available Los moluscos terrestres son un grupo altamente diverso cuyo trabajo investigativo en Nicaragua ha sido mayoritariamente en la vertiente del Pacífico de Nicaragua. Evaluar el potencial de estas especies como indicadores de la perdida de la masa boscosa así como de su recuperación ayudará el impacto de las actividades humanas en esta biota de escasa movilidad. La colectas de conchas y especímenes fué realizada en bosques húmedos, nubosos y secos en los departamentos de Rivas y Jinotega en hábitats específicos dentro de la matrix del paisaje. Las identificaciones a posteriori fueron hechas para evitar el sesgo de identificaciones en especies de taxonomía debatible. Los hábitats forestales continuos mostraron valores mayores en biodiversidad que otros hábitats dentro de la matrix, mostrando que existe fidelidad de hábitat para la comunidad de caracoles en general. Esta alta fidelidad, muestra la importancia de este grupo cuando tratamos de obtener especies de fidelidad alta, ayudando a explicar cómo la perdida de bosque afecta a la fauna.

  5. ESTUDO DO APROVEITAMENTO DAS VÍSCERAS DOS MOLUSCOS ESCARGOT (Achatina fulica E ARUÁ (Pomacea lineata PARA INCORPORAÇÃO EM RAÇÃO ANIMAL

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    S. E. R. BARBOZA

    2008-09-01

    Full Text Available

    O objetivo deste trabalho foi estudar o aproveitamento das vísceras - subprodutos, dos moluscos escargot e aruá. As vísceras foram processadas na forma de farinha e suas características físico-químicas (composição centesimal, cálcio, fósforo, digestibilidade em pepsina, índice de acidez e microbiológicas (Salmonella sp foram comparadas aos padrões de qualidades exigidas pela Legislação (6.198, de 26/12/74, e o Decreto 76.986, de 06/01/76 do Ministério da Agricultura e Abastecimento para a comercialização de produtos destinados à alimentação animal. Os resultados obtidos permitiram verificar que as farinhas de vísceras de ambas espécies podem ser utilizadas como matérias primas, constituindo ótimas fontes de nutrientes para a incorporação em rações animais.

  6. PROCESSAMENTO E AVALIAÇÃO SENSORIAL DA CARNE DOS MOLUSCOS ESCARGOT (Achatina fulica E ARUÁ (Pomacea lineata

    Directory of Open Access Journals (Sweden)

    S. H. R. BARBOZA

    2009-01-01

    Full Text Available

    O presente trabalho foi desenvolvido com o objetivo de avaliar sensorialmente os produtos do processamento da carne dos moluscos escargot (Achatina fulica e aruá (Pomacea lineata. Foram realizados dois processamentos em conserva (enlatado: triturada e defumada. Na avaliação sensorial da carne triturada observou-se diferença significativa entre os produtos, favorável ao escargot com valor médio de aceitação igual a 5,35 e 4,76 para o aruá. Para os produtos elaborados defumados observou-se uma aceitação igual para as duas espécies (escargot = 4,82 e aruá = 4,49. Esses resultados de aceitação nos permitem admitir que os produtos são tecnicamente e sensorialmente viáveis para consumo (aceitação acima de 60% para os dois casos, mas com tendências ligeiramente favoráveis de preferência para os produtos elaborados com carne de escargot.

  7. Pronase acutely modifies high voltage-activated calcium currents and cell properties of Lymnaea neurons.

    Science.gov (United States)

    Hermann, P M; Lukowiak, K; Wildering, W C; Bulloch, A G

    1997-12-01

    Pronase E ('pronase') is one of the proteolytic enzymes that are used in preparative procedures such as cell isolation and to soften the sheath of invertebrate ganglia. Although several effects of proteolytic enzymes on the physiology of non-neuronal tissues have been described, the effects of these enzymes on central neurons have received little attention. We examined the effects of bath-applied pronase on neurons in the Lymnaea central nervous system and in vitro. Pronase caused action potential broadening in neurons that exhibit a shoulder on the repolarization phase of their action potentials. This effect of pronase was accompanied by, although unrelated to, a depolarization and decrease in action potential interval. Some, but not all, effects of pronase in the central nervous system were reversible. For example, the decreases in membrane potential and action potential interval were both reversed after approximately 1 h of washing with saline. However, the effect of pronase on the action potential duration was not reversed after a period of 90 min. The modulation of action potential width prompted us to examine Ca2+ currents. Exposure to pronase resulted in an increase in both peak and late high voltage-activated Ca2+ currents in isolated neurons. Pronase neither changed the inactivation rate nor caused a shift in the current-voltage relationship of the current. The changes in action potential duration could be prevented by application of 0.1 mM Cd2+, indicating that the action potential broadening caused by pronase depends on Ca2+ influx. This is the first systematic study of the acute and direct actions of pronase on Ca2+ currents and cell properties both in the CNS and in vitro.

  8. Differences in neuronal activity explain differences in memory forming abilities of different populations of Lymnaea stagnalis.

    Science.gov (United States)

    Braun, Marvin H; Lukowiak, Kai; Karnik, Vikram; Lukowiak, Ken

    2012-01-01

    The ability to learn and form long-term memory (LTM) can enhance an animal's fitness, for example, by allowing them to remember predators, food sources or conspecific interactions. Here we use the pond snail, Lymnaea stagnalis, to assess whether variability between natural populations (i.e., strains) in memory forming capabilities correlates with electrophysiological properties at the level of a single neuron, RPeD1. RPeD1 is a necessary site of LTM formation of aerial respiratory behaviour following operant conditioning. We used strains from two small, separate permanent ponds (TC1 and TC2). A comparison of the two populations showed that the TC1 strain had enhanced memory forming capabilities. Further, the behavioural phenotype of enhanced memory strain was explained, in part, by differences in the electrophysiology of RPeD1. Compared to RPeD1 from the naive TC2 strain, RPeD1 from the TC1 strain has both a decreased resistance and decreased excitability. Moreover, 24h after a single 0.5h training session, those membrane properties, as well as the firing and bursting rate, decrease further in the TC1 strain but not in the TC2 strain. The initial differences in RPeD1 properties in the TC1 strain coupled with their ability to further change these properties with a single training session suggests that RPeD1 neurons from the TC1 strain are "primed" to rapidly form memory. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. On the Ultrastructure and Function of Rhogocytes from the Pond Snail Lymnaea stagnalis.

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    Maria Kokkinopoulou

    Full Text Available Rhogocytes, also termed "pore cells", occur as solitary or clustered cells in the connective tissue of gastropod molluscs. Rhogocytes possess an enveloping lamina of extracellular matrix and enigmatic extracellular lacunae bridged by cytoplasmic bars that form 20 nm diaphragmatic slits likely to act as a molecular sieve. Recent papers highlight the embryogenesis and ultrastructure of these cells, and their role in heavy metal detoxification. Rhogocytes are the site of hemocyanin or hemoglobin biosynthesis in gastropods. Based on electron microscopy, we recently proposed a possible pathway of hemoglobin exocytosis through the slit apparatus, and provided molecular evidence of a common phylogenetic origin of molluscan rhogocytes, insect nephrocytes and vertebrate podocytes. However, the previously proposed secretion mode of the respiratory proteins into the hemolymph is still rather hypothetical, and the possible role of rhogocytes in detoxification requires additional data. Although our previous study on rhogocytes of the red-blooded (hemoglobin-containing freshwater snail Biomphalaria glabrata provided much new information, a disadvantage was that the hemoglobin molecules were not unequivocally defined in the electron microscope. This made it difficult to trace the exocytosis pathway of this protein. Therefore, we have now performed a similar study on the rhogocytes of the blue-blooded (hemocyanin-containing freshwater snail Lymnaea stagnalis. The intracellular hemocyanin could be identified in the electron microscope, either as individual molecules or as pseudo-crystalline arrays. Based on 3D-electron microscopy, and supplemented by in situ hybridization, immunocytochemistry and stress response experiments, we provide here additional details on the structure and hemocyanin biosynthesis of rhogocytes, and on their response in animals under cadmium and starvation stress. Moreover, we present an advanced model on the release of synthesized

  10. Seasonal variation in abiotic factors and toxicity of thymol against the snail Lymnaea acuminata

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    Shefali Srivastava

    2013-01-01

    Full Text Available Toxicity of thymol against Lymnaea acuminata was conducted in each month of the year 2010-2011. The 24, 48, 72 and 96 h LC50 values of a molluscicide thymol were determined, with the concomitant estimation of levels of temperature, pH, dissolved oxygen, carbon dioxide and electrical conductivity, both in control and test water. On the basis of a 24h toxicity assay, it was observed that 24h LC50 value of 6.41 mg/l in month of May, was most effective in killing the snails, while the thymol was least effective in month of April, when its 24h LC50 was 15.25 mg/l. There was a significant positive correlation between LC50 of thymol and levels of carbon dioxide/ pH of water in corresponding months. On the contrary, a negative correlation was noted between LC50 of thymol and dissolved oxygen/ temperature of test water in the same months. In order to confirm that relationship between toxicity and abiotic factors is not coincidental, activity of acetylcholinesterase (AChE, acid phosphatase (ACP and alkaline phosphatase (ALP in the nervous tissue of control as well as sublethal thymol (60% of 24hLC50 treated snail, were assayed during each of the 12 months of the same year. A significant positive rank correlation was noted between AChE/ACP/ALP activity and corresponding sublethal treatment of thymol. Maximum inhibition of AChE, ACP and ALP activity was observed in the month of May. This study shows conclusively that the best time to control the L. acuminata population with thymol is during the month of May to July.

  11. Toxicity of Chlorophyllin against Lymnaea acuminata at Different Wavelengths of Visible Light.

    Science.gov (United States)

    Chaturvedi, Divya; Singh, Vinay Kumar

    2016-08-01

    Fasciolosis is a water and food-borne disease caused by the liver fluke Fasciola hepatica and Fasciola gigantica. This disease is widespread in different parts of the world. Lymnaeidae and Planorbidae snails are the intermediate hosts of these flukes. Snail population management is a good tool to control fasciolosis because gastropods represent the weakest link in the life-cycle of trematodes. Chlorophyll can be extracted from any green plant. Chlorophyllin was prepared from spinach in 100% ethanol by using different types of chemicals. The chlorophyll obtained from spinach was transformed into water-soluble chlorophyllin. In the present paper, toxicity of chlorophyllin against the snail Lymnaea acuminata was time and concentration dependent. The toxicity of extracted and pure chlorophyllin at continuous 4 h exposure of sunlight was highest with lethal concentration (LC50) of 331.01 mg/L and 2.60 mg/L, respectively, than discontinuous exposure of sunlight up to 8 h with LC50 of 357.04 mg/L and 4.94 mg/L, respectively. Toxicity of extracted chlorophyllin was noted in the presence of different monochromatic visible lights. The highest toxicity was noted in yellow light (96 h, LC50 392.77 mg/L) and the lowest in green light (96 h, LC50 833.02 mg/L). Chlorophyllin in combination with solar radiation or different wavelength of monochromatic visible lights may become a latent remedy against the snail L. acuminata. It was demonstrated that chlorophyllin was more toxic in sunlight. Chlorophyllin is ecologically safe and more economical than synthetic molluscicides which have the potential to control the incidence of fasciolosis in developing countries.

  12. Toxicity of Chlorophyllin against Lymnaea acuminata at Different Wavelengths of Visible Light

    Science.gov (United States)

    Chaturvedi, Divya; Singh, Vinay Kumar

    2016-01-01

    Fasciolosis is a water and food-borne disease caused by the liver fluke Fasciola hepatica and Fasciola gigantica. This disease is widespread in different parts of the world. Lymnaeidae and Planorbidae snails are the intermediate hosts of these flukes. Snail population management is a good tool to control fasciolosis because gastropods represent the weakest link in the life-cycle of trematodes. Chlorophyll can be extracted from any green plant. Chlorophyllin was prepared from spinach in 100% ethanol by using different types of chemicals. The chlorophyll obtained from spinach was transformed into water-soluble chlorophyllin. In the present paper, toxicity of chlorophyllin against the snail Lymnaea acuminata was time and concentration dependent. The toxicity of extracted and pure chlorophyllin at continuous 4 h exposure of sunlight was highest with lethal concentration (LC50) of 331.01 mg/L and 2.60 mg/L, respectively, than discontinuous exposure of sunlight up to 8 h with LC50 of 357.04 mg/L and 4.94 mg/L, respectively. Toxicity of extracted chlorophyllin was noted in the presence of different monochromatic visible lights. The highest toxicity was noted in yellow light (96 h, LC50 392.77 mg/L) and the lowest in green light (96 h, LC50 833.02 mg/L). Chlorophyllin in combination with solar radiation or different wavelength of monochromatic visible lights may become a latent remedy against the snail L. acuminata. It was demonstrated that chlorophyllin was more toxic in sunlight. Chlorophyllin is ecologically safe and more economical than synthetic molluscicides which have the potential to control the incidence of fasciolosis in developing countries. PMID:27688849

  13. Serotonergic and dopaminergic influence of the duration of embryogenesis and intracapsular locomotion of Lymnaea stagnalis L.

    Science.gov (United States)

    Filla, Adrienn; Hiripi, L; Elekes, K

    2004-01-01

    The role of the dopaminergic and serotonergic system was studied during the embryonic development of the pond snail Lymnaea stagnalis, with special attention to the effect of dopamine and serotonin as well as their agonists and antagonists on the rotation of the veliger larvae, and to the effect of precursors and inhibitors of the synthetizing enzymes on the duration of the embryonic life. Serotonin, D-lysergic acid diethylamide and N,N-dimethyltryptamine increased at a concentration of 1 microM the rotation by 50%, 90% and 87% respectively, and among them D-Lysergic acid diethylamide was found to be the most potent agonist. Other serotonergic agonists and antagonists enhanced the frequency of the rotation (from 165% to 355%) at higher threshold concentrations in the following rank order: methysergid > tryptamine > 2,5-dimethoxy-4-iodoamphetamine > 5-carboxyamidotryptamine > bromo-lysergic acid diethylamide > 7-methyltryptamine. Application of 1-(2-methoxyphenyl) piperazine decreased the rotation by 76%. The reuptake inhibitor desipramine completely blocked the rotation and killed the embryos. Dopaminergic agonists accelerated the rotation by 62% to 233%, and their effect was ranged as follows: dopamine > apomorphine > m-tyramine approximately equal to p-tyramine. Chlorpromazine at 100 microM concentration killed the embryos. At a concentration of 100 microg/ml, tyrosine, the precursor of DA, slowed down the embryonic development by increasing the duration of the embryonic life from 8 to 10 days. Decarboxylase inhibitors, alpha-methyl-3,4-dihydroxyphenyl-alanine (25 microg/ml) and m-hydroxybenzylhydrazin (5 microg/ml), killed 50% of the embryos, meanwhile the rest hatched ten days later, compared to the control animals. The development was partially blocked by the serotonin precusor L-tryptophane (50 microg/ml). Trytophan hydroxylase blocker, p-chlorphenylalanine (50 microg/ml) resulted in a distortion of the body pattern of the embryos, and prevented the hatching

  14. Assessment of anoxia tolerance and photoperiod dependence of GABAergic polarity in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Buck, Leslie T; Bond, Hilary C; Malik, Aqsa

    2017-01-01

    The pond snail Lymnaea stagnalis is reported to be anoxia-tolerant and if the tolerance mechanism is similar to that of the anoxia-tolerant painted turtle, GABA should play an important role. A potentially confounding factor investigating the role of GABA in anoxia tolerance are reports that GABA has both inhibitory and excitatory effects within L. stagnalis central ganglion. We therefore set out to determine if seasonality or photoperiod has an impact on: 1) the anoxia-tolerance of the intact pond snail, and 2) the response of isolated neuroganglia cluster F neurons to exogenous GABA application. L. stagnalis maintained on a natural summer light cycle were unable to survive any period of anoxic exposure, while those maintained on a natural winter light cycle survived a maximum of 4h. Using intracellular sharp electrode recordings from pedal ganglia cluster F neurons we show that there is a photoperiod dependent shift in the response to GABA. Snails exposed to a 16h:8h light:dark cycle in an environmental chamber (induced summer phenotype) exhibited hyperpolarizing inhibitory responses and those exposed to a 8h:16h light:dark cycle (induced winter phenotype) exhibited depolarizing excitatory responses to GABA application. Using gramicidin-perforated patch recordings we also found a photoperiod dependent shift in the reversal potential for GABA. We conclude that the opposing responses of L. stagnalis central neurons to GABA results from a shift in intracellular chloride concentration that is photoperiod dependent and is likely mediated through the relative efficacy of cation chloride co-transporters. Although the physiological ramifications of the photoperiod dependent shift are unknown this work potentially has important implications for the impact of artificial light pollution on animal health. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Lymnaea schirazensis, an overlooked snail distorting fascioliasis data: genotype, phenotype, ecology, worldwide spread, susceptibility, applicability.

    Science.gov (United States)

    Bargues, María Dolores; Artigas, Patricio; Khoubbane, Messaoud; Flores, Rosmary; Glöer, Peter; Rojas-García, Raúl; Ashrafi, Keyhan; Falkner, Gerhard; Mas-Coma, Santiago

    2011-01-01

    Lymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity. A ten-year study in Iran, Egypt, Spain, the Dominican Republic, Mexico, Venezuela, Ecuador and Peru, demonstrated that such heterogeneity is not due to susceptibility differences, but to a hitherto overlooked cryptic species, Lymnaea schirazensis, confused with the main vector Galba truncatula and/or other Galba/Fossaria vectors. Nuclear rDNA and mtDNA sequences and phylogenetic reconstruction highlighted an old evolutionary divergence from other Galba/Fossaria species, and a low intraspecific variability suggesting a recent spread from one geographical source. Morphometry, anatomy and egg cluster analyses allowed for phenotypic differentiation. Selfing, egg laying, and habitat characteristics indicated a migration capacity by passive transport. Studies showed that it is not a vector species (n = 8572 field collected, 20 populations): snail finding and penetration by F. hepatica miracidium occur but never lead to cercarial production (n = 338 experimentally infected). This species has been distorting fasciolid specificity/susceptibility and fascioliasis geographical distribution data. Hence, a large body of literature on G. truncatula should be revised. Its existence has henceforth to be considered in research. Genetic data on livestock, archeology and history along the 10,000-year post-domestication period explain its wide spread from the Neolithic

  16. Palaeartic gastropod gains a foothold in the dominion of endemics: range expansion and morphological change of Lymnaea (Radix) auricularia in Lake Baikal

    NARCIS (Netherlands)

    Stift, M.; Michel, E.; Sitnikova, N.L.; Mamonova, Y.; Sherbakov, D.Y.

    2004-01-01

    In and around the endemic-dominated Lake Baikal, palaearctic species are generally restricted to shallow, sheltered bays and in- and out-flowing river floodplains. However, we observed populations of the palaearctic snail Lymnaea (Radix) auricularia on the steep, rocky littoral of Lake Baikal

  17. Palaeartic gastropod gains a foothold in the dominion of endemics: range expansion and morphological change of Lymnaea (Radix) auricularia in Lake Baikal

    NARCIS (Netherlands)

    M. Stift; E. Michel; N.L. Sitnikova; Y. Mamonova; D.Y. Sherbakov

    2004-01-01

    In and around the endemic-dominated Lake Baikal, palaearctic species are generally restricted to shallow, sheltered bays and in- and out-flowing river floodplains. However, we observed populations of the palaearctic snail Lymnaea (Radix) auricularia on the steep, rocky littoral of Lake Baikal proper

  18. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil

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    Abílio Francisco José Pegado

    1998-01-01

    Full Text Available Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.

  19. Ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil

    Directory of Open Access Journals (Sweden)

    Francisco José Pegado Abílio

    1998-04-01

    Full Text Available Foi registrada a ocorrência de Lymnaea columella (Gastropoda: Lymnaeidae, primeiro hospedeiro intermediário da Fasciola hepatica, para o Estado da Paraíba, Brasil, associado a macrófitas aquáticas.

  20. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    NARCIS (Netherlands)

    D. Zivkovic (Dana); R. Créton (Robbert); G. Zwaan (Gideon); W.C. de Bruijn (Wim); M.R. Dohmen (M.René)

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity

  1. The Fungitoxicity of Four Fungicides to Pseudoperonospora cubensis in Hunan Province%4种杀菌剂对湖南省黄瓜霜霉病菌的毒力作用

    Institute of Scientific and Technical Information of China (English)

    任磊; 张松柏; 张德咏; 张胜平; 彭静; 刘勇

    2012-01-01

    [Aims] The aim is to clarify the fungitoxicity of the fungicides with different action modes against Pseudoperonospora cubensis in Hunan province- [Methods] The fungitoxicity of four fungicides to Pseudoperonospora cubensis of Hunan province was tested by leaf disc floating method. [Results] The results showed the fungitoxicity (EC50) in metalaxyl, cymoxanil, azoxystrobin and dimethomorph to Pseudoperonospora cubensis were 15,613-17.266, 10.13-13.465, 3,834-5.444 and 9.122-9.915 mg/L, respectively. [Conclusions] The resistance ratio to azoxystrobin was high, and the resistance ratios to the other three fungicides were lower. However, the index of relative toxicity of azoxystrobin was significantly higher than that of the other three fungicides.%[目的]明确不同作用机理的杀菌剂对湖南省黄瓜霜霉病菌的毒力.[方法]采用叶盘漂浮法测定4种不同作用机理的杀菌剂(甲霜灵、霜脲氰、嘧菌酯、烯酰吗啉)对湖南省不同地区黄瓜霜霉病菌的毒力.[结果]湖南省黄瓜霜霉病菌对甲霜灵、霜脲氰、嘧菌酯、烯酰吗啉的毒力(EC50)分别为15.613~17.266、10.313~13.465、3.834~5.444、9.122~9.915 mg/L.[结论]湖南省黄瓜霜霉病菌对嘧菌酯的抗性倍数较高,其他3种杀菌剂抗性倍数均较低;但是嘧菌酯相对毒力指数显著高于其他3种杀菌剂.

  2. Embryogenesis of the histaminergic system in the pond snail, Lymnaea stagnalis L.: an immunocytochemical and biochemical study.

    Science.gov (United States)

    Hegedus, E; Kaslin, J; Elekes, K

    2004-01-01

    Embryogenesis of the histaminergic system in the pond snail, Lymnaea stagnalis, was investigated by means of immunocytochemistry and HPLC assay. From the earliest onset of the of histamine-immunoreactive (HA-IR) elements, the labelled neurons were confined to the pedal, cerebral and buccal ganglia, whereas no IR cells within the pleural, parietal and visceral ganglia were detectable during the embryogenesis. Peripheral projections of the embryonic HA-IR neurons were missing. No transient HA-IR neurons could be found either inside or outside the CNS. The first HA-IR elements appeared at about E55% of embryonic development, at the beginning of metamorphosis, and were represented by three pairs of neurons located in the cerebral ganglia. Following metamorphosis, four pairs of HA-IR neurons were added; two of them occurred in the pedal (E65% stage of development) and two in the buccal (E90% stage of development) ganglia. During embryogenesis, HA-IR fibers were present in the cerebro-pedal connectives and in the cerebral, pedal and buccal commissures, whereas only little arborization could be observed in the neuropil of the ganglia. HPLC measurements revealed a gradual increase of HA content in the embryos during development, corresponding well to the course of the appearance of immunolabeled elements. It is suggested that the developing HAergic system plays a specific role in the process of gangliogenesis and CNS plasticity of embryonic Lymnaea.

  3. Tertiary combination of freeze-dried urine of Indian breeds of cow with plant products against snail Lymnaea acuminata.

    Science.gov (United States)

    Kumar, Shiv; Singh, D K; Singh, Vinay Kumar

    2012-10-15

    Snail Lymnaea acuminata is the intermediate host of liver fluke Fasciola gigantica, which cause endemic fasciolosis among cattle population of eastern Uttar Pradesh. Control of snail population by molluscicides is one of the effective methods to control fasciolosis. In the present study molluscicidal activity of tertiary combination of freeze-dried urine of different Indian breeds of cow Sahiwal, Geer and Tharparkar with Annona squamosa seed powder, Ferula asafoetida root latex, Azadirachta indica oil and Camellia sinensis leaves have been tested against Lymnaea acuminata. It was noted that the toxicity of tertiary combination (1:1:5) of cow urine kept for 15 days in sunlight or laboratory condition with different plant products were highly toxic against snail L. acuminata. 96 h LC50 of tertiary combinations with Sahiwal urine kept for 15 days in sunlight with A. squamosa, F. asafoetida, A. indica oil and C. sinensis were 35.47 mg L(-1), 37.13 mg L(-1), 33.66 mg L(-1), respectively higher than the Geer and Tharparkar. The toxicity of Sahiwal urine kept for 15 days in laboratory condition with A. squamosa and C. sinensis (96 h LC50 28.28 mg L(-1)) was more potent than the all other combinations. Cow urine in combination with plant product can be used for effective control of snail.

  4. Determinaçao de metais classificados como de importância toxicológica no molusco bivalve Anadara notabilis (Röding, 1798): Encontrado em Galinhos, Rio grande do norte, Brasil Determination of metals of toxicological importance in the bivalve Anadara notabilis (Röding, 1798) of Galinhos, coast of Rio grande do norte, Brazil

    OpenAIRE

    Marcos A Urbano de Araújo; Maria F Vitória de Moura; Genickson Borges de Carvalho

    2010-01-01

    Os moluscos bivalves são consumidos por todo o mundo, constituindo-se em um recurso natural de boa aceitação pela população. Foi escolhido o molusco Anadara notabilis (conhecido como Xibiu ou Búzio) para este trabalho pelo seu tamanho característico, bem maior que os mariscos mais comuns, e também por não ter sido encontrado na literatura nenhuma informação toxicológica sobre esta classe de moluscos. Todos os íons metálicos foram determinados por espectroscopia de emissão ótica com plasma ind...

  5. Effect of nitrogen availability on the oxygen consumption during mineralization of Scirpus cubensis from Infernão Lagoon (São Paulo-Brazil = Efeito da disponibilidade de nitrogênio no consumo de oxigênio durante a mineralização de Scirpus cubensis da Lagoa do Infernão (São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Romilda Maria Alves de Lemos

    2007-04-01

    Full Text Available This study evaluated the influence of nitrogen additions in the oxygenuptake during decomposition of Scirpus cubensis, through laboratory assays. The dissolved oxygen, pH, electrical conductivity (EC and water temperature were measured. The results showed an initial acidification that decreased gradually, indicating great release of reduced organic matter and subsequent CO2 formation. The decomposition chambers with greater nitrate concentrations exhibited higher pH mean values. The temporal variation of EC showed a small increase and an abrupt increase with increasing nitrate concentrations. The maximum oxygen uptake increased up to 6.37 mg L-1 of nitrate, then decreased. The deoxygenation rate showed an opposite trend from that observed for the oxygen uptake. The coefficients and maximum oxygen consumption related to the particulate detritusmineralization tended to increase with increasing nitrate concentration. The increase in nitrate levels affected the decomposition of each organic matter fraction in different ways,with the particulate organic matter being more easily degraded in richer nitrate concentrations than the dissolved organic matter.Neste estudo, avaliou-se a influência de adições de nitrogênio no consumo de oxigênio durante a decomposição de Scirpus cubensis, por meio de ensaios de laboratório. Foram determinados: as concentrações de oxigênio dissolvido, o pH, a condutividade elétrica e a temperatura da água. Os resultados mostraram acidificação inicial quediminuíram gradualmente, indicando grande liberação de matéria orgânica reduzida e formação subseqüente de CO2. As câmaras de decomposição com maiores concentrações de nitrato apresentaram valores de pH mais alto. A condutividade elétrica mostrou pequenoincremento com o passar do tempo e aumento abrupto com a intensificação das concentrações de nitrato. O consumo de oxigênio máximo global aumentou até a concentração de nitrato de 6,37 mg L

  6. Validación de la metodología para la determinación de ácido domoico (biotoxina ASP en moluscos bivalvos por cromatografía líquida de alto rendimiento (HPLC

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    Pérez Calderón Ruth

    2002-07-01

    Full Text Available El ácido domoico es una neurotoxina, competidora del glutamato, que se halla en los mares y océanos del mundo. Objetivo: Validar la metodología para determinar ácido domoico (biotoxina ASP por cromatografía líquida de alto rendimiento (HPLC . Materiales y métodos: Se analizó una muestra de 1 000 g de moluscos bivalvos (conchas de abanico extraídos de la zona sur del Perú. Para la precisión del sistema se evaluó: tiempo de retención, área y altura; la exactitud del método se estimó en función de recuperación, analizándose el material de referencia (MUS 1B y mediante la contaminación de moluscos con solución de ácido domoico. La sensibilidad del método se evaluó por la determinación del límite de cuantificación (LOQ. Resultados: En la detección lineal se obtuvo un coeficiente de correlación r=0,99 y la precisión del método tuvo un coeficiente de correlación de 3,61%. Los porcentajes de recuperación fueron 92,52% y 91,10%, respectivamente, obtuviéndose un límite de cuantificación (LOQ de 1,30 mg/g AD. Conclusión: Nuestra validación demostró que el método en estudio es preciso, exacto, lineal y altamente sensible para ser utilizado en el control de calidad de moluscos bivalvos.

  7. Estudo da correlação entre molusco contagioso e dermatite atópica em crianças A study of the correlation between molluscum contagiosum and atopic dermatitis in children

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    Maria Bandeira de Melo Paiva Seize

    2011-08-01

    Full Text Available FUNDAMENTOS: É bastante divulgado, sem a fundamentação científica necessária, que a infecção por molusco contagioso tende a ser mais frequente e de maior intensidade nos pacientes acometidos por dermatite atópica. Tal fato motivou a realização deste trabalho. OBJETIVOS: Avaliar a prevalência de associação de dermatite atópica e molusco contagioso; avaliar se, nos pacientes com dermatite atópica, a infecção por molusco contagioso é mais recorrente e/ou disseminada e se a ocorrência de eczema perimolusco, prurido e/ou infecção é mais prevalente que nos pacientes sem dermatite atópica. MÉTODOS: Avaliaram-se 284 crianças de ambos os sexos, com diagnóstico de molusco contagioso e/ ou dermatite atópica. RESULTADOS: Apenas 13,4% dos pacientes apresentavam ambas as doenças. O número de áreas anatômicas afetadas por molusco contagioso, a ocorrência de eczema perimolusco e prurido foram maiores nos pacientes com dermatite atópica associada. Não houve diferença significativa de frequência de infecção secundária associada às lesões de molusco contagioso nos pacientes com e sem dermatite atópica. CONCLUSÃO: A prevalência da ocorrência de dermatite atópica e molusco contagioso associados foi baixa. Não houve diferença significativa na recorrência da infecção por molusco contagioso e na quantidade de lesões nos pacientes com e sem dermatite atópica. O número de áreas anatômicas afetadas por lesões de molusco contagioso, a presença de eczema perimolusco e de prurido foram maiores nos pacientes com dermatite atópica. Não houve diferença significativa na ocorrência de infecção bacteriana secundária nos grupos com e sem dermatite atópicaBACKGROUND: Although no scientific evidence has yet been published, it is widely understood that molluscum contagiosum tends to be more common and more intense in patients with atopic dermatitis. This lack of evidence led to the development of the present study

  8. Investigations into the mechanism of lead toxicity to the freshwater pulmonate snail, Lymnaea stagnalis.

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    Brix, Kevin V; Esbaugh, Andrew J; Munley, Kathleen M; Grosell, Martin

    2012-01-15

    The freshwater pulmonate snail, Lymnaea stagnalis, is the most sensitive aquatic organism tested to date for Pb with an estimated EC20 for juvenile snail growth of 3 μg l⁻¹. A previous study supported the hypothesis that this hypersensitivity to Pb was due to an extremely high Ca²⁺ uptake rate needed to support shell formation. The current study sought to build upon this working hypothesis and develop a mechanistic predictive model for inhibition of snail growth as a function of Pb exposure. Initial experiments confirmed previous predictions that juvenile snails have net Ca²⁺ uptake rates of 7000-8000 nmol g⁻¹ h⁻¹, approximately 100-fold higher than observed in a typical freshwater fish. However, an initial time course study revealed that the onset of growth inhibition occurs at least 4d prior to inhibition of net Ca²⁺ flux in Pb-exposed snails indicating the latter is not the primary mechanism of action. Qualitative observations during this experiment indicated snail feeding was inhibited in a dose-dependent manner. A subsequent experiment demonstrated that when food is withheld from snails for even 24 h, net Ca²⁺ uptake is significantly (∼50%) reduced. A second time course study demonstrated quantitatively that snail feeding is inhibited by Pb exposure by up to 98% at relatively high Pb concentrations (57 μg l⁻¹) but no inhibition was observed at ≤ 10 μg l⁻¹ Pb indicating feeding inhibition is not causing observed growth effects at concentrations approximating the EC20 of 3 μg l⁻¹ Pb. A final experiment testing whether Pb-induced growth effects are related to inhibition of carbonic anhydrase activity in the snail mantle also failed to demonstrate an effect. We conclude that while both feeding and net Ca²⁺ uptake in snails are affected by Pb exposure, they appear to be secondary effects. The primary mechanism of action explaining L. stagnalis hypersensitivity to Pb remains to be identified. Copyright © 2011 Elsevier B

  9. Lymnaea schirazensis, an Overlooked Snail Distorting Fascioliasis Data: Genotype, Phenotype, Ecology, Worldwide Spread, Susceptibility, Applicability

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    Bargues, María Dolores; Artigas, Patricio; Khoubbane, Messaoud; Flores, Rosmary; Glöer, Peter; Rojas-García, Raúl; Ashrafi, Keyhan; Falkner, Gerhard; Mas-Coma, Santiago

    2011-01-01

    Background Lymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity. Methodology/Principal Findings A ten-year study in Iran, Egypt, Spain, the Dominican Republic, Mexico, Venezuela, Ecuador and Peru, demonstrated that such heterogeneity is not due to susceptibility differences, but to a hitherto overlooked cryptic species, Lymnaea schirazensis, confused with the main vector Galba truncatula and/or other Galba/Fossaria vectors. Nuclear rDNA and mtDNA sequences and phylogenetic reconstruction highlighted an old evolutionary divergence from other Galba/Fossaria species, and a low intraspecific variability suggesting a recent spread from one geographical source. Morphometry, anatomy and egg cluster analyses allowed for phenotypic differentiation. Selfing, egg laying, and habitat characteristics indicated a migration capacity by passive transport. Studies showed that it is not a vector species (n = 8572 field collected, 20 populations): snail finding and penetration by F. hepatica miracidium occur but never lead to cercarial production (n = 338 experimentally infected). Conclusions/Significance This species has been distorting fasciolid specificity/susceptibility and fascioliasis geographical distribution data. Hence, a large body of literature on G. truncatula should be revised. Its existence has henceforth to be considered in research. Genetic data on livestock, archeology and history along the 10,000-year

  10. Lymnaea schirazensis, an overlooked snail distorting fascioliasis data: genotype, phenotype, ecology, worldwide spread, susceptibility, applicability.

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    María Dolores Bargues

    Full Text Available BACKGROUND: Lymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity. METHODOLOGY/PRINCIPAL FINDINGS: A ten-year study in Iran, Egypt, Spain, the Dominican Republic, Mexico, Venezuela, Ecuador and Peru, demonstrated that such heterogeneity is not due to susceptibility differences, but to a hitherto overlooked cryptic species, Lymnaea schirazensis, confused with the main vector Galba truncatula and/or other Galba/Fossaria vectors. Nuclear rDNA and mtDNA sequences and phylogenetic reconstruction highlighted an old evolutionary divergence from other Galba/Fossaria species, and a low intraspecific variability suggesting a recent spread from one geographical source. Morphometry, anatomy and egg cluster analyses allowed for phenotypic differentiation. Selfing, egg laying, and habitat characteristics indicated a migration capacity by passive transport. Studies showed that it is not a vector species (n = 8572 field collected, 20 populations: snail finding and penetration by F. hepatica miracidium occur but never lead to cercarial production (n = 338 experimentally infected. CONCLUSIONS/SIGNIFICANCE: This species has been distorting fasciolid specificity/susceptibility and fascioliasis geographical distribution data. Hence, a large body of literature on G. truncatula should be revised. Its existence has henceforth to be considered in research. Genetic data on livestock, archeology and history

  11. Los moluscos de la ofrenda 107 del Templo Mayor de Tenochtitlan The mollusks of the offering 107 of the Great Temple of Tenochtitlan

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    Norma Valentín-Maldonado

    2007-10-01

    Full Text Available El propósito de este trabajo es dar a conocer la identificación biológica de las especies de moluscos encontradas en la ofrenda 107, que fue depositada en la séptima etapa constructiva del Templo Mayor de Tenochtitlan (1502-1521. La identificación se realizó por medio de la bibliografía especializada, y en el caso de algunos ejemplares por comparación directa con los de la colección malacológica de referencia del Laboratorio M. en C. Ticul Álvarez Solórzano. Se identificaron 246 ejemplares de moluscos marinos; 191 pertenecen a la clase Gastropoda (78% y 55 a la Bivalvia (22%. El número más frecuente de especies proviene de la provincia caribeña, siendo su hábitat principal las playas arenosas y las costas rocosas. Los desgastes y fracturas observadas en la mayoría de los esqueletos calcáreos de animales ya muertos, indican que fueron recolectados en las playas; por otro lado, el buen estado de preservación de algunos de ellos sugiere que se capturaron vivos, y en ciertos casos mediante buceo. A través de este estudio ha sido posible obtener datos, como la procedencia, el hábitat, la coloración natural y la selectividad de las diferentes especies identificadas, los cuales contribuyen al conocimiento de aspectos económicos e ideológicos de la cultura mexica.The purpose of this work is to report the identifications of the species of mollusks found in offering 107, which was buried in the seventh stage of the construction of the Great Temple of Tenochtitlan (1502-1521. This was done by direct comparison with specimens in the malacological reference collection of the Ticul Álvarez Solorzano Laboratory and the literature. The 246 marine individuals belonging to two classes were identified; 191 belonging to the Gastropoda (78% and 55 to the Bivalvia (22%. The largest number of species came from the Caribbean Province, with species from sandy beaches and rocky coasts being most common. The abrasions and fractures observed in

  12. Moluscos vectores da esquistossomose mansônica no lado leste do Rio São Francisco, no Estado da Bahia

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    Air Colombo Barretto

    1981-06-01

    Full Text Available Pela primeira vez foi realizado um levantamento malacológico de espécies vectoras de Schistosoma mansoni na região do lado Oeste do Rio São Francisco, no Estado da Bahia. Observou-se que nas áreas onde a única espécie encontrada foi B. straminea, a esquistossomose não constitui um problema médico. Entretanto, nas áreas onde foi coletado B. glabraata, além de B. straminea, a esquistossomose se apresenta com características de alta endemicidade. A ausência de moluscos, apesar da abundância de água, foi observada em extensas áreas, quase despovoadas. Esse quadro poderá se modificar em futuro bem próximo, devido â construção de novas estradas, bem como pela implantação de projetos de irrigação. Baseados nos presentes resultados e, em dados da literatura, os autores correlacionam a distribuição geográfica das espécies vectoras com a endemicidade da esquistossomose no Brasil.Snail vectors of Schistosomiasis mansoni west of the San Francisco River, State of Bahia, were surveyed for the first time. In areas where the only vector found was Biomphalaria straminea, Schistosomiasis does not appear to be a medical problem. However, in areas where B. glabrata was collected, in addition t B. straminea, schistosomiasis was highly endemic. In spite of an abundance of surface water, no sanils were found in sparsely populated areas. This could change as a result of proposed schemes of new roads and irrigation systems. The results presented here have been combined with previously data in order to demonstrate a correia tion between the geografic distribuition of different species of snail vectors and the endemicity of schistosomiasis mansoni throughout Brazil.

  13. Moluscos Poliplacóforos del litoral atlántico del sur de la Península Ibérica

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    Carmona Zalvide, M. P.

    2000-12-01

    Full Text Available In this paper, an updated check-list of the polyplacophoran species from Sagres (Portugal to Strait of Gibraltar is present. Twenty taxa are recorded in this area: Lepidopleurus cajetanus, Leptochiton cancellatus, Leptochiton algesirensis, Leptochiton scabridus, Callochiton septemvalvis, Callochiton euplaeae, Lepidochitona cinerea, Lepidochitona corrugata, Lepidochitona canariensis, Lepidochitona monterosatoi, Lepidochitona kaasi, Lepidochitona severianoi, Chaetopleura angulata, Ischnochiton rissoi, Chiton olivaceus, Chiton corallinus, Chiton phaesolinus, Acanthochitona fascicularis and Acanthochitona crinita. From these species, Lepidochitona canariensis, L simrothi, Callochiton septemvalvis and Lepidochitona monterosatoi amplify their geographical distribution to Southern Atlantic coast of southern Iberian Peninsula.

    Se aporta el catálogo de los Moluscos Poliplacóforos de las costas atlánticas del sur de la Península Ibérica, desde Sagres (Portugal hasta Gibraltar. Se cita un total de 20 taxones (Lepidopleurus cajetanus, Leptochiton cancellatus, Leptochiton algesirensis, Leptochiton scabridus, Callochiton septemvalvis, Callochiton euplaeae, Lepidochitona cinerea, Lepidochitona corrugata, Lepidochitona canariensis, Lepidochitona monterosatoi, Lepidochitona kaasi, Lepidochitona severianoi, Chaetopleura angulata, Ischnochiton rissoi, Chiton olivaceus, Chiton corallinus, Chiton phaesolinus, Acanthochitona fascicularis y Acanthochitona crinita todos ellos pertenecientes al dominio litoral. La captura de Lepidochitona canariensis y L. simrothi en aguas atlánticas ibéricas constituye la primera cita para el suratlántico ibérico. A su vez se amplía la distribución a esta zona de Callochiton septemvalvis y de Lepidochitona monterosatoi.

  14. Los moluscos terrestres (Mollusca: Gastropoda de Costa Rica: clasificación, distribución y conservación

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    Zaidett Barrientos Llosa

    2010-12-01

    Full Text Available Los moluscos terrestres son un grupo muy poco estudiado a nivel mundial. Hay 183 especies reportadas para Costa Rica, 30% son endémicas y 7% posiblemente están extintas. Se espera que en el país haya alrededor de 400 especies, de más del 95% se desconoce su biología, ecología, distribución, genética y otros campos de estudio. En Costa Rica las familias con mayor número de especies son Spiraxidae, Orthalicidae y Subulinidae. No obstante, es posible que Euconulidae sea aun más diversa, pues habitan las zonas altas del país que es en donde menos trabajo se ha hecho. El estudio de regiones altas aumentará el porcentaje de endemismo. Los futuros trabajos malacológicos taxonómicos, biológicos y ecológicos deben considerar la poca movilidad de este grupo, su tendencia a formar especies nuevas en simpatría, la especificidad de requerimientos de microhábitat, el hermafroditismo, la alta tasa de evolución (10% por millón de años y la divergencia entre especies (2-30%. Para proteger adecuadamente la biodiversidad de la malacofauna costarricense, se requiere de estudios que determinen la distribución y abundancia de las especies y el efecto del uso de la tierra y del climático.

  15. Phyto-adaptogens protect against environmental stress-induced death of embryos from the freshwater snail Lymnaea stagnalis.

    Science.gov (United States)

    Boon-Niermeijer, E K; van den Berg, A; Wikman, G; Wiegant, F A

    2000-10-01

    The main purpose of the studies presented in this paper is twofold: 1) to evaluate whether phyto-adaptogens (Acanthopanax senticosus and Rhodiola rosea) are able to exert a protective action against stress-induced death of embryos of the pond snail Lymnaea stagnalis; and 2) whether a possible protective action by phyto-adaptogens can be explained by the induction of heat shock proteins. Enhancement in resistance by phyto-adaptogens was studied by applying plant extracts for a period of 20 hours to 3-day old larvae of the pond snail Lymnaea stagnalis. Subsequently they were exposed to a high and toxic dose of different environmental stressors. The following stress conditions were selected: a physical stress condition (heat shock: 43 degrees C for 4 minutes), an oxidative stress condition (superoxide radicals induced by menadione (600 microM for 2 hours)) and heavy metal-induced stress (copper (150 microM for 1 hour) or cadmium (20 microM during 1 hour)). Both Acanthopanax and Rhodiola exert a strong protective action against a lethal heat shock. These adaptogens also significantly protect against the negative effect of superoxide radicals as induced by menadione. With respect to the protective action against exposure to heavy metals a small but significant protection was observed against intoxication with copper or cadmium by the phyto-adaptogens. In summary, there appears to be a difference in efficiency in enhancing resistance to the various stress conditions used (heat shock>menadione>copper>cadmium). Based on the results presented in this paper, we can conclude that phyto-adaptogens are able to enhance the resistance against the different stress conditions tested in developing individuals of Lymnaea. Although the degree to which resistance is enhanced appears to depend on the type of stressor applied, our results confirm the definition of phyto-adaptogens as being universal enhancers of non-specific resistance against different kinds of stress conditions. With

  16. Genetic variability of Brazilian populations of Lymnaea columella (Gastropoda: Lymnaeidae), an intermediate host of Fasciola hepatica (Trematoda: Digenea).

    Science.gov (United States)

    Cardoso, Paula Cristina Marques; Caldeira, Roberta Lima; Lovato, Maria Bernadete; Coelho, Paulo Marcos Zech; Berne, Maria Elisabeth Aires; Müller, Gertrud; Carvalho, Omar dos Santos

    2006-03-01

    In Brazil, Lymnaea columella is the most important intermediate host of Fasciola hepatica, the etiological agent of fasciolosis, which is a parasitic disease of veterinarian and human importance. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variability within and among nine Brazilian populations of L. columella comprising 205 individuals. A number of four primers were used for analysis of molecular variance (AMOVA). Out of 83 RAPD markers, 63 (76%) were polymorphic and revealed 119 unique RAPD profiles. The levels of genetic variability found in the populations were low and most of the genetic variation was interpopulational (81.6%) when compared to intrapopulational variability (18.4%). These results are in accordance with the dynamics and distribution of the populations analyzed.

  17. Sympatric and allopatric combinations of Lymnaea columella and Fasciola hepatica from southern and south-eastern Brazil.

    Science.gov (United States)

    Coelho, L H L; Lima, W S; Guimaraes, M P

    2009-09-01

    Experimental infections of Lymnaea columella with Fasciola hepatica were carried out to test the effect of sympatric and allopatric combinations between parasite and host, by using snails and flukes from southern and south-eastern Brazil. Four groups of 50 snails were infected with four miracidia per snail: two groups in sympatric and two groups in allopatric combinations. Sympatric combinations between parasite and host were more efficient than allopatric ones when snails from Itajubá were used, but the opposite was observed in infections involving snails from Pelotas. The sympatric association between L. columella and F. hepatica from Itajubá was significantly higher than in the other combinations. We concluded that the host-parasite relationship between L. columnella and F. hepatica may vary according to the geographical origin of the snails and flukes involved.

  18. The competitive interaction of snails Thiara scabra and Physa doopi on the snail Lymnaea rubiginosa under laboratory conditions

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    Sarwitri Endah Estuningsih

    1998-03-01

    Full Text Available The competitive interaction of the snails Thiara scabra and Physa doopi against the snail Lymnaea rubiginosa, the intermediate host ofFasciola gigantica has been studied. Aquaria, 60 x 40 x 20 cm and 30 x 20 x 10 cm in size were used, and the two snail species were introduced in different proportion . The results over a one year period showed that the competition between snail L. rubiginosa and T. scabra or P. doopi has started after 8 months as demonstrated by the reduction of the population ofL. rubiginosa and increasing the population of T. scabra or P. doopi. The competitive interaction does not seem to be due to competition for food but to a chemical factors, possibly water-soluble pheromones. The other explanation is discussed .

  19. Effect of non target snails on some biological of Lymnaea natalensis snails and their infection to Fasciola gigantica.

    Science.gov (United States)

    Bakry, Fayez A; Hamdi, Salwa A H

    2006-12-01

    The influence of non-target freshwater snails (Melanoides tuberculata and Planorbis planorbis) on the capacity of Fasciola egg production F. gigantica miracidia to infect Lymnaea natalensis and their effect on mortality and growth rates showed that the snails exhibited a competitive ability against L. natalensis. The mortality rate existed in mixed cultures with snails was greatly increased, and increased with increase of snails number. The egg production and growth rate were negatively affected by the presence of M. tuberculata and P. planorbis which was more pronounced when snails were at higher ratio lL: 10D. Also, the snails showed significant degree of reduction in infection rate of L. natalensis with F. gigantica miracidia.

  20. Population dynamics of Lymnaea columella and its natural infection by Fasciola hepatica in the State of Minas Gerais, Brazil.

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    Coelho, L H L; Lima, W S

    2003-03-01

    Studies on the population dynamics and natural infection of Lymnaea columella by Fasciola hepatica were carried out from September 1999 to December 2000 in a low-lying area near Itajubá in the Brazilian State of Minas Gerais. A total of 626 snails were collected monthly at nine different sites, counted, and dissected to search for larvae of F. hepatica. The highest populations of L. columella were reached in October of 1999 and August of 2000, and the highest natural infection rates of snails by F. hepatica were reached in September 1999 (5.2%) and July 2000 (3.9%). The removal by farmers of aquatic plants from the drainage furrows caused a drastic reduction in this snail population.

  1. Histology and Cytochemistry of the Neurosecretory Cells (NSC of the Freshwater Snail Lymnaea luteola (Lamarck Mollusca: Gastropoda

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    Vijaya Kumar Kanapala

    2015-01-01

    Full Text Available Four types of neurosecretory (NS cells are noticed in the cerebral, pleural, buccal and pedal ganglion of the freshwater snail Lymnaea luteola. According to the size and staining properties they are classified as A, B, C and D type cells. These are giant cells, medium cells, small cells and smallest cells. Type ‘A’ cells are largest of the all cells and measures about 0.0600-0.0800 mm in diameter. The B cells are smaller than ‘A’ cells and are ranges from 0.035-0.040 mm in diameter. The ‘C’ and ‘D’ cells are smaller than the ‘A’ and ‘B ‘cells and more or less oval in shape. The histochemical observations reveal that the neurosecretory material is rich in carbohydrates, disulphides, sulfhydryl group, protein bound amino groups, glycoprotein and lipids.

  2. Comparative shell morphology of Lymnaea (Bullastra) cumingiana (Pulmonata: Lymnaeidae) and related taxa in the Indo-Pacific region.

    Science.gov (United States)

    Monzon, R B; Kitikoon, V; Thammapalerd, N; Temcharoen, P; Sornmani, S; Viyanant, V

    1993-09-01

    Comparative shell morphology using both quantitative and qualitative parameters was employed to investigate the taxonomic relationship between the endemic Philippine species, Lymnaea (Bullastra) cumingiana and five other lymnaeid "species" in the Indo-Pacific region, namely: L. (Radix) quadrasi (Philippines). L. (Radix) rubiginosa (Indonesia), L. (Radix) rubiginosa (Thailand), L. (Radix) viridis (Guam) and L. (Radix) viridis (Hong Kong). Fifty randomly chosen adult specimens of each species were studied and compared, although only field-collected specimens were studied for the first four groups and laboratory-raised specimens for the last two group. Results strongly suggested that L. cumingiana is a distinct species among the rest. L. quadrasi, L. rubiginosa (Indonesia) and L. rubiginosa (Thailand) exhibited great affinity towards each other. Likewise, the two geographical isolates of L. viridis were practically identical to each other except for some minor size differences.

  3. Structure-dependent effects of amyloid-β on long-term memory in Lymnaea stagnalis.

    Science.gov (United States)

    Ford, Lenzie; Crossley, Michael; Vadukul, Devkee M; Kemenes, György; Serpell, Louise C

    2017-05-01

    Amyloid-β (Aβ) peptides are implicated in the causation of memory loss, neuronal impairment, and neurodegeneration in Alzheimer's disease. Our recent work revealed that Aβ 1-42 and Aβ 25-35 inhibit long-term memory (LTM) recall in Lymnaea stagnalis (pond snail) in the absence of cell death. Here, we report the characterization of the active species prepared under different conditions, describe which Aβ species is present in brain tissue during the behavioral recall time point and relate the sequence and structure of the oligomeric species to the resulting neuronal properties and effect on LTM. Our results suggest that oligomers are the key toxic Aβ1-42 structures, which likely affect LTM through synaptic plasticity pathways, and that Aβ 1-42 and Aβ 25-35 cannot be used as interchangeable peptides. © 2017 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

  4. Effects of DDT and permethrin on neurite growth in cultured neurons of chick embryo brain and Lymnaea stagnalis.

    Science.gov (United States)

    Ferguson, C A; Audesirk, G

    1990-01-01

    The pesticides permethrin and 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT), dissolved in either ethanol (EtOH) or dimethylsulphoxide (DMSO), were studied to determine their effect on neurite growth from cultured neurons of Lymnaea stagnalis and embryonic chicks. Both of these toxins decreased the percentage of neurons growing neurites, mean neurite length, and number of neurites/cell in a dose-dependent manner. DMSO increased the toxicity of permethrin and DDT in L. stagnalis neurons. EtOH was not used as a solvent with the embryonic chick cultures. Pre-existing neurites of L. stagnalis neurons exposed to permethrin regressed in a dose- and time-dependent manner. These two toxins may affect neurite outgrowth through interference with intracellular calcium regulation.

  5. Explotación de recursos costeros durante el Neolítico en el área de la Reserva de Urdaibai : Los moluscos de la cueva de Kobaederra (Kortezubi, Bizkaia

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    Gutierrez Zugasti, F. Igor

    2009-01-01

    Full Text Available El aprovechamiento de recursos malacológicos ha sido una constante en las estrategias de subsistencia de los cazadores recolectores que poblaron la región cantábrica durante el Paleolítico superior y el Mesolítico. En los inicios del Neolítico, esta actividad continúa vigente incluso en contextos que presentan evidencias de agricultura y ganadería, lo que podría estar indicando una transición relativamente lenta en el proceso de cambio en las formas productivas. Un ejemplo de este tipo lo encontramos en la cueva de Kobaederra (Kortezubi, Bizkaia, excavada entre los años 1995 y1998. El análisis del material malacológico indica que la explotación de moluscos se ha llevado a cabo en el cercano estuario de río Oka, en zonas de roca (Ostrea edulis, arena/fango (Ruditapes decussatus y fango (Scrobicularia plana. A partir del análisis biométrico se ha establecido que la presión humana sobre estos recursos no fue excesiva. Por otra parte, esta escasa presión y el descenso de las acumulaciones de moluscos a lo largo del tiempo parecen indicar una pérdida de importancia de estos recursos tras la adopción de la agricultura y la ganadería.

  6. Is there redundancy in bioengineering for molluscan assemblages on the rocky shores of central Chile? ¿Existe redundancia en la bioingeniería de los ensambles de moluscos de las costas rocosas de Chile central?

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    BRENDAN P KELAHER

    2007-06-01

    través de sus propias estructuras físicas e incrementan la diversidad local. En costas rocosas existen grandes solapamientos en la composición de las comunidades asociadas a bioingenieros que forman habitats frondosos (algas o mitílidos. Nosotros investigamos la potencial redundancia en la provisión de este tipo de habitat comparando ensambles faunísticos asociados a mantos de Perumytilus purpuratus y frondas de Corallina officinalis var. chilenis, Gelidium chilense y Gastroclonium cylindricum. En tres oportunidades, entre septiembre de 2003 y enero de 2004, muestreamos ensambles de moluscos asociados a cada uno de estos bioingenieros, en alturas de mareas similares en dos áreas rocosas de Chile central. De las 31 especies de moluscos identificados, 30 fueron encontrados en Corallina y 19-22 fueron identificados en los otros habitat. El conjunto de especies asociado a cada bioingeniero se sobrepone ampliamente, demostrando el potencial de redundancia en la provisión de habitat y poca especificidad de habitat. Sin embargo, análisis multivariados y univariados mostraron que los bioingenieros, con excepción de Gastroclonium, contenían un ensamble de moluscos único en al menos uno de los periodos de muestreo, ya sea en la variación en la frecuencia de ocurrencia, riqueza y abundancia total. Estudios recientes han destacado diversos procesos antropogénicos y naturales que influencian directamente la diversidad y composición de especies en bioingenieros de costas rocosas. Se demuestra que para la costa de Chile central la pérdida de cualquier de los bioingenieros analizados no alteraría sustancialmente el conjunto total de especies de moluscos, alojados en ellos. Sin embargo, la pérdida de cualquier bioingeniero, excepto Gastroclonium, resultaría en una disminución local de la biodiversidad debido a que cada uno de los ensambles de moluscos en Perumytilus, Corallina y Gelidium, contiene una estructura comunitaria significativamente diferente, en al menos

  7. Identification and functional expression of a family of nicotinic acetylcholine receptor subunits in the central nervous system of the mollusc Lymnaea stagnalis.

    Science.gov (United States)

    van Nierop, Pim; Bertrand, Sonia; Munno, David W; Gouwenberg, Yvonne; van Minnen, Jan; Spafford, J David; Syed, Naweed I; Bertrand, Daniel; Smit, August B

    2006-01-20

    We described a family of nicotinic acetylcholine receptor (nAChR) subunits underlying cholinergic transmission in the central nervous system (CNS) of the mollusc Lymnaea stagnalis. By using degenerate PCR cloning, we identified 12 subunits that display a high sequence similarity to nAChR subunits, of which 10 are of the alpha-type, 1 is of the beta-type, and 1 was not classified because of insufficient sequence information. Heterologous expression of identified subunits confirms their capacity to form functional receptors responding to acetylcholine. The alpha-type subunits can be divided into groups that appear to underlie cation-conducting (excitatory) and anion-conducting (inhibitory) channels involved in synaptic cholinergic transmission. The expression of the Lymnaea nAChR subunits, assessed by real time quantitative PCR and in situ hybridization, indicates that it is localized to neurons and widespread in the CNS, with the number and localization of expressing neurons differing considerably between subunit types. At least 10% of the CNS neurons showed detectable nAChR subunit expression. In addition, cholinergic neurons, as indicated by the expression of the vesicular ACh transporter, comprise approximately 10% of the neurons in all ganglia. Together, our data suggested a prominent role for fast cholinergic transmission in the Lymnaea CNS by using a number of neuronal nAChR subtypes comparable with vertebrate species but with a functional complexity that may be much higher.

  8. Effects of in vitro lead exposure on voltage-sensitive calcium channels differ among cell types in central neurons of Lymnaea stagnalis.

    Science.gov (United States)

    Audesirk, G; Audesirk, T

    1989-01-01

    The effects of acute in vitro lead exposure on slowly inactivating voltage-sensitive calcium channels in central neurons of the freshwater pond snail Lymnaea stagnalis were studied under voltage clamp. Three physiologically distinct cell types were used: two subsets of the B cell cluster (Bpos and Bneg) and the pedal giant neuron (RPeD1). In Bpos neurons, 5 nM free Pb2+ irreversibly inhibited current flow through calcium channels by 38 +/- 10%. In Bneg neurons, 5 nM free Pb2+ slightly inhibited inward currents (12 +/- 6%) and may have shifted their voltage dependence to more depolarized voltages. The inhibition and voltage shift were irreversible. In RPeD1 neurons, Pb2+ caused a small, statistically insignificant inhibition of inward current (5 nM free Pb2+; 18 +/- 19%; 30 nM free Pb2+: 31 +/- 23%). The effects of Pb2+ were fully reversible. These data indicate that (1) voltage-sensitive calcium channels in Lymnaea neurons are inhibited by nanomolar concentrations of free Pb2+; (2) there are multiple types of calcium channels in Lymnaea neurons; and (3) the effects of in vitro lead exposure differ qualitatively among channel types.

  9. Ciclo reproductivo del molusco Atrina maura (Pterioidea: Pinnidae en un sistema lagunar costero, al sur del Pacífico tropical mexicano

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    Claudia Angel-Pérez

    2007-12-01

    Full Text Available De febrero de 1997 a febrero de 1998, se recolectaron mensualmente muestras aleatorias del molusco Atrina maura en el sistema lagunar Corralero-Alotengo, Oaxaca, México. Se extrajeron las partes blandas para lavarlas in situ y fijarlas en solución Davison. En el laboratorio se pesaron para obtener los índices gonadosomático (IGS y de rendimiento muscular (IRM, y mediante cortes histológico de las gónadas se caracterizó el ciclo reproductivo. Esta población se reproduce casi todo el año, con dos periodos reproductivos importantes: uno de abril a julio y otro de octubre a noviembre, y una sola época de reposo, en agosto y septiembre. El ciclo reproductivo tiene una relación directa con el IGS e inversa con el IRM. Hay evidencias de una relación estrecha de las época de desove y postdesove con la temperatura del agua (R = 0.991, p 0.002. Las hembras predominaron casi todo el año, aunque esta proporción solo tuvo diferencias estadísticamente significativas en noviembre (X²: p= 0.05Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae in a coastal lagoon system of the Mexican South Pacific. From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSI and the muscle yield index (MYI were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSI and a reverse relationship with the MYI. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p = 0.002. Females dominate numerically

  10. Ocorrência de linhagens humana e silvestre de Schistosoma mansoni, na pré-amazônia: I - estudo em moluscos Occurrence of wild and human strains of Schistosoma mansoni in lower Amazonia: I - study in moluscs

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    Othon de Carvalho Bastos

    1982-10-01

    Full Text Available Foram isoladas na região da Baixada Maranhense (Brasil, linhagens humana (H e silvestre(S de Schistosoma mansoni a partir de miracídios eclodidos de ovos encontrados em fezes de doentes humanos autóctones da Região e de fígados de roedores silvestres naturalmente infectados. Biomphalaria glabrata, descentes de caramujos coletados no campo, foram expostos, isoladamente, aos miracídios H e S, mantidos isolados em moluscário e observados durante 100 dias. Moluscos normais foram mantidos nas mesmas condições de ambiente em que foram submetidos os infectados e tomados como controle da experiência. Foram anotados os indices de infecção dos moluscos, as datas da eliminação de cercárias, quantidade de larvas eliminadas e mortalidade dos moluscos. Os dados sugeriram melhor adaptação do esquistossomo da linhagem H à B. glabrata. A linhagem S, por sua vez, foi três vezes mais virulenta do que a linhagem H. Estes dados foram comparados com os encontrados na literatura especializada e verificado diversidades nos comportamentos parasitológicos das linhagens em estudo, quando comparados com os encontrados nas linhagens H e S oriundas do Vale do Rio Paraíba do Sul, no Estado de São Paulo (Brasil.The wild (W and human (H strains of Schistosoma mansoni were isolated in the Lowland Region of the Maranhão State (Brazil. The snail progenies from Biomphalaria glabrata collected from that region were exposed to the W miracidia, obtained from livers of wild rodents, and H miracidia from eggs in human stools. A control gruop of normal snails was kept in the same conditions as the infected one. The date of the elimination of cercariae, the quantity of eliminated larvae, the infection index of the moluscs and the mortality rate of the snails were recorded. These data suggested better adaptation of the H strain to B. glabrata. The W strain presented three times more virulence to snails than the H strain. These results were compared with published

  11. New geographic and depth records for deep-water mollusks in the Gulf of California, Mexico Nuevos registros geográficos y batimétricos para moluscos de mar profundo en el golfo de California, México

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    Pablo Zamorano

    2007-12-01

    Full Text Available Six oceanographic cruises (Talud IV-IX were made in the southern Gulf of California aboard the R/V El Puma of the Universidad Nacional Autónoma de México. A total of 56 species of deep-sea mollusks were identified, of which 16 (13 Bivalvia, 2 Gastropoda, 1 Scaphopoda represent either a new geographic or bathymetric record, or both.A partir de 6 campañas oceanográficas (Talud IV-IX realizadas en el sur del golfo de California a bordo del B/O "El Puma" de la Universidad Nacional Autónoma de México, se identificaron 56 especies de moluscos de aguas profundas. De ellas 16 (13 Bivalvia, 2 Gastropoda, 1 Scaphopoda corresponden a un nuevo registro geográfico, batimétrico o ambos.

  12. Abundância e infecção do molusco Biomphalaria glabrata pelo Schistosoma mansoni no Estado do Rio de Janeiro, Brasil Abundance and Schistosoma mansoni infection of the snail Biomphalaria glabrata, Brazil

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    Alexandre Giovanelli

    2001-12-01

    Full Text Available OBJETIVOS: Investigar a distribuição espacial, a abundância e os índices de infecção natural de Biomphalaria glabrata, hospedeiro intermediário do Schistosoma mansoni, em localidade do Estado do Rio de Janeiro, RJ, Brasil. MÉTODOS: Na localidade de Pamparrão, município de Sumidouro, RJ, as coletas de moluscos foram realizadas bimestralmente no período de junho de 1991 a novembro de 1995. Foram estabelecidos 23 pontos de coleta ao longo do córrego Pamparrão e três de seus afluentes. Os moluscos capturados foram levados ao laboratório para diagnóstico da infecção. Para a análise dos dados, foram usados o coeficiente de Spearman (nível de 0,5% de significância e o teste de qui-quadrado. RESULTADOS: A abundância populacional de B. glabrata foi bastante variável ao longo do tempo e entre os ambientes amostrados. A maioria dos pontos de coleta apresentou correlação negativa com a pluviosidade. O afluente B destacou-se dos demais corpos d'água por apresentar taxas de infecção de B. glabrata elevadas (acima dos 25% em alguns pontos de coleta e persistentes. Foram encontrados mais moluscos infectados na estação seca do que na chuvosa (chi²=20,08; p=0,001. CONCLUSÕES: A população de moluscos foi influenciada negativamente pelo regime de chuvas, principalmente no córrego Pamparrão. A época de estiagem também parece ter favorecido a ocorrência de infecção, provavelmente devido ao menor volume de água dos córregos, o que aumentaria as chances de encontro do parasita com seu hospedeiro intermediário.OBJECTIVES: To investigate the spatial distribution, abundance and natural schistosomiasis infection levels in the snail Biomphalaria glabrata, the intermediate host of Schistosoma mansoni in an area of the State of Rio de Janeiro, Brazil. METHODS: In the Pamparrão area, Sumidouro county, RJ, Brazil, snail captures were carried out every other month from June 1991 to November 1995. There were 23 collecting sites along

  13. Diversidade de moluscos associados à alga parda do gênero Sargassum C. Agardh, 1820 em costões da Ilha de São Sebastião, litoral norte do Estado de São Paulo

    OpenAIRE

    Sarah Lemes Freitas

    2015-01-01

    Resumo: A macrofauna associada a espécies de Sargassum é relativamente bem conhecida no litoral do Estado de São Paulo, porém os estudos foram realizados essencialmente em áreas continentais. Investigações sobre a malacofauna associada a Sargassum ainda são raras no país e não há comparações sobre a composição e variação das comunidades de moluscos associados a esta alga parda, em relação a faces continentais e oceânicas de ilhas. Desse modo, neste estudo, procurou-se conhecer a composição, r...

  14. Prospecção do molusco invasor Limnoperna fortunei (Dunker, 1857 nos principais corpos hídricos do estado do Paraná, Brasil

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    Debora Pestana

    2010-01-01

    Full Text Available Foram realizadas coletas nos principais corpos hídricos do Paraná objetivando a prospecção de larvas do mexilhão dourado, Limnoperna fortunei (Dunker, 1857. Essa espécie de molusco vem colonizando diversos corpos hídricos na América do Sul desde sua introdução na Argentina, em 1991. Já atingiu os rios Paraná e Paraguai, tendo sua presença reportada nos estados do Mato Grosso do Sul, Paraná, São Paulo, Minas Gerais e Rio Grande do Sul. As coletas foram feitas no inverno e na primavera de 2007 e no verão e no outono de 2008, em 14 pontos amostrais ao longo dos rios Iguaçu, Piquiri, Ivaí (afluentes do rio Paraná e Tibagi (afluente do rio Paranapanema. O presente estudo determinou a presença da espécie ao longo de todos os pontos do rio Iguaçu, em dois pontos do rio Piquiri e um ponto amostral do rio Tibagi. No rio Ivaí, sua presença não foi detectada em nenhum dos pontos, em nenhuma estação do ano. Com base nos resultados obtidos, foi feito um mapa de ocorrência da espécie no estado do Paraná. Esses resultados são úteis para embasar a tomada de decisão a respeito do avanço da espécie, no sentido de monitorar sua presença e/ou prevenir sua entrada em outros corpos hídricos do estado.Were collected in the main water bodies of the state of Paraná (Brazil it will seek the golden mussel larvae, Limnoperna fortunei (Dunker, 1857. This species of mussel is colonizing various water bodies in South America since its introduction in Argentina in 1991. Already reached the Paraná and Paraguay rivers, having reported their presence in the states of Mato Grosso do Sul, Paraná, Sao Paulo, Minas Gerais and Rio Grande do Sul. Samples were collected in winter and spring of 2007 and summer and autumn 2008 in 14 sampling points along the rivers Iguaçu, Piquiri, Ivaí (tributaries of the Paraná River and Tibagi (tributary of the Paranapanema river. This study determined the presence of this species throughout all parts of the

  15. Molluscicidal activity of Ferula asafoetida, Syzygium aromaticum and Carum carvi and their active components against the snail Lymnaea acuminata.

    Science.gov (United States)

    Kumar, Pradeep; Singh, D K

    2006-06-01

    The molluscicidal activity of dried root latex powder of Ferula asafoetida, flower-bud powder of Syzygium aromaticum and seed powder of Carum carvi against the snail Lymnaea acuminata was studied. The molluscicidal activity of all the three plant products was found to be both time and concentration dependent. The toxicity of S. aromaticum flower-bud powder (96 h LC(50):51.98 mg/l) was more pronounced than that of root latex powder of F. asafoetida (96 h LC(50):82.71 mg/l) and seed powder of C. carvi (96 h LC(50):140.58 mg/l). Ethanol extract was more toxic than other organic extracts. The ethanol extract of S. aromaticum (24h LC(50):83.53 mg/l) was more effective than that of F. asafoetida (24h LC(50):132.31 mg/l) and C. carvi (24h LC(50):130.61 mg/l) in killing the test animals. The 96 h LC(50) of column purified fraction of seed powder of C. carvi was 5.40 mg/l whereas those of flower-bud powder of S. aromaticum and dried root latex powder of F. asafoetida were 7.87 and 9.67 mg/l, respectively. The product of F. asafoetida, S. aromaticum and C. carvi may be used as potent molluscicides.

  16. Development of an embryo toxicity test with the pond snail Lymnaea stagnalis using the model substance tributyltin and common solvents.

    Science.gov (United States)

    Bandow, Cornelia; Weltje, Lennart

    2012-10-01

    The development of a chronic mollusc toxicity test is a current work item on the agenda of the OECD. The freshwater pond snail Lymnaea stagnalis is one of the candidate snail species for such a test. This paper presents a 21-day chronic toxicity test with L. stagnalis, focussing on embryonic development. Eggs were collected from freshly laid egg masses and exposed individually until hatching. The endpoints were hatching success and mean hatching time. Tributyltin (TBT), added as TBT-chloride, was chosen as model substance. The selected exposure concentrations ranged from 0.03 to 10 μg TBT/L (all as nominal values) and induced the full range of responses. The embryos were sensitive to TBT (the NOEC for mean hatching time was 0.03 μg TBT/L and the NOEC for hatching success was 0.1 μg TBT/L). In addition, data on maximum limit concentrations of seven common solvents, recommended in OECD aquatic toxicity testing guidelines, are presented. Among the results, further findings as average embryonic growth and mean hatching time of control groups are provided. In conclusion, the test presented here could easily be standardised and is considered useful as a potential trigger to judge if further studies, e.g. a (partial) life-cycle study with molluscs, should be conducted.

  17. Bioaccumulation of copper and toxic effects on feeding, growth, fecundity and development of pond snail Lymnaea luteola L.

    Science.gov (United States)

    Das, Sangita; Khangarot, B S

    2011-01-15

    We studied the bioaccumulation and the toxic effects of Cu on survival, number of eggs and eggmasses laying, embryo development, growth, and food consumption in an Indian pond snail, Lymnaea luteola L. exposed for 7 weeks. Copper caused loss of chemoreception, locomotion and inhibited food consumption significantly during 7 weeks of exposure. Food consumption in Cu exposed snails significantly decreased and at 56 and 100 μg L(-1), snail stopped feeding activity. Mean number of eggmasses or eggs significantly decreased in Cu concentrations during the 7 week study. The percentage hatching decreased in Cu concentrations but there was more than 95% hatched in control in 10-11 days after spawning. Egg development was completely inhibited at 100 μg L(-1), while abnormal embryonic development observed at 32 and 56 μg L(-1) of Cu. The Cu concentration in tissues increased in Cu treated snails and bioaccumulation factor ranged from 2.3 to 18.7. Snail growth at 5.6 and 10 μg L(-1) was reduced by 6.2% and 16.9%, respectively. The study revealed that snail embryos and adults could be used as in vivo test models for ecotoxicological studies. Findings of present study are helpful for advancing water quality guidelines for protecting aquatic biota.

  18. Modelling effects of diquat under realistic exposure patterns in genetically differentiated populations of the gastropod Lymnaea stagnalis.

    Science.gov (United States)

    Ducrot, Virginie; Péry, Alexandre R R; Lagadic, Laurent

    2010-11-12

    Pesticide use leads to complex exposure and response patterns in non-target aquatic species, so that the analysis of data from standard toxicity tests may result in unrealistic risk forecasts. Developing models that are able to capture such complexity from toxicity test data is thus a crucial issue for pesticide risk assessment. In this study, freshwater snails from two genetically differentiated populations of Lymnaea stagnalis were exposed to repeated acute applications of environmentally realistic concentrations of the herbicide diquat, from the embryo to the adult stage. Hatching rate, embryonic development duration, juvenile mortality, feeding rate and age at first spawning were investigated during both exposure and recovery periods. Effects of diquat on mortality were analysed using a threshold hazard model accounting for time-varying herbicide concentrations. All endpoints were significantly impaired at diquat environmental concentrations in both populations. Snail evolutionary history had no significant impact on their sensitivity and responsiveness to diquat, whereas food acted as a modulating factor of toxicant-induced mortality. The time course of effects was adequately described by the model, which thus appears suitable to analyse long-term effects of complex exposure patterns based upon full life cycle experiment data. Obtained model outputs (e.g. no-effect concentrations) could be directly used for chemical risk assessment.

  19. Does water chemistry affect the dietary uptake and toxicity of silver nanoparticles by the freshwater snail Lymnaea stagnalis?

    Science.gov (United States)

    López-Serrano Oliver, Ana; Croteau, Marie-Noële; Stoiber, Tasha L.; Tejamaya, Mila; Römer, Isabella; Lead, Jamie R.; Luoma, Samuel N.

    2014-01-01

    Silver nanoparticles (AgNPs) are widely used in many applications and likely released into the aquatic environment. There is increasing evidence that Ag is efficiently delivered to aquatic organisms from AgNPs after aqueous and dietary exposures. Accumulation of AgNPs through the diet can damage digestion and adversely affect growth. It is well recognized that aspects of water quality, such as hardness, affect the bioavailability and toxicity of waterborne Ag. However, the influence of water chemistry on the bioavailability and toxicity of dietborne AgNPs to aquatic invertebrates is largely unknown. Here we characterize for the first time the effects of water hardness and humic acids on the bioaccumulation and toxicity of AgNPs coated with polyvinyl pyrrolidone (PVP) to the freshwater snail Lymnaea stagnalis after dietary exposures. Our results indicate that bioaccumulation and toxicity of Ag from PVP-AgNPs ingested with food are not affected by water hardness and by humic acids, although both could affect interactions with the biological membrane and trigger nanoparticle transformations. Snails efficiently assimilated Ag from the PVP-AgNPs mixed with diatoms (Ag assimilation efficiencies ranged from 82 to 93%). Rate constants of Ag uptake from food were similar across the entire range of water hardness and humic acid concentrations. These results suggest that correcting regulations for water quality could be irrelevant and ineffective where dietary exposure is important.

  20. Distribution of serotonin and FMRF-amide in the brain of Lymnaea stagnalis with respect to the visual system

    Institute of Scientific and Technical Information of China (English)

    Oksana P.TUCHINA; Valery V.ZHUKOV; Victor B.MEYER-ROCHOW

    2012-01-01

    Despite serotonin's and FMRF-amide's wide distribution in the nervous system of invertebrates and their importance as neurotransmitters,the exact roles they play in neuronal networks leaves many questions.We mapped the presence of serotonin and FMRF-amide-immunoreactivity in the central nervous system and eyes of the pond snail Lymnaea stagnalis and interpreted the results in connection with our earlier findings on the central projections of different peripheral nerves.Since the chemical nature of the intercellular connections in the retina of L.stagnalis is still largely unknown,we paid special attention to clarifying the role of serotonin and FMRF-amide in the visual system of this snail and compared our findings with those reported from other species.At least one serotonin- and one FMRF-amidergic fibre were labeled in each optic nerve,and since no cell bodies in the eye showed immunoreactivity to these neurotransmitters,we believe that efferent fibres with somata located in the central ganglia branch at the base of the eye and probably release 5HT and FMRF-amide as neuro-hormones.Double labelling revealed retrograde transport of neurobiotin through the optic nerve,allowing us to conclude that the central pathways and serotonin- and FMRF-amide-immunoreactive cells and fibres have different locations in the CNS in L.stagnalis.The chemical nature of the fibres,which connect the two eyes in L.stagnalis,is neither serotoninergic nor FMRF-amidergic.

  1. Enzyme inhibition by molluscicidal agents of Bauhinia variegata and Mimusops elengi in the nervous tissue of Lymnaea acuminata

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    Kanchan Lata Singh

    2015-10-01

    Full Text Available Objective: To evaluate the effect of enzymatic activity in the nervous tissue of snail Lymnaea acuminata (L. acuminata by Bauhinia variegata (B. variegata and Mimusops elengi (M. elengi and their active molluscicidal components quercetin and saponin. Methods: Treatment of sublethal concentration (40% and 80% of 96-h LC50 in vivo of column-purified fraction of B. variegata leaf and M. elengi bark and their molluscicidal agents quercetin and saponin inhibit the acetylcholinesterase (AChE, acid and alkaline phosphatase (ACP and ALP activities in the nervous tissue of L. acuminata. Results: AChE activity was more inhibited than ACP and ALP in snail exposed to columnpurified fraction of M. elengi bark and saponin. Among all the treatments the highest inhibition in AChE activity (27.77% was noted in snail L. acuminata exposed to 80% of 96-h LC50 of saponin at 96-h exposure period. Conclusions: It can be concluded from the present study that inhibition of AChE, ACP and ALP by B. variegata leaf (quercetin and M. elengi bark (saponin in snail L. acuminata could be the cause of snail mortality.

  2. Distribution and habitats of the snail Lymnaea truncatula, intermediate host of the liver fluke Fasciola hepatica, in South Africa.

    Science.gov (United States)

    de Kock, K N; Wolmarans, C T; Bornman, M

    2003-12-01

    This paper focuses on the geographical distribution and habitats of Lymnaea truncatula, the intermediate, snail host of the liver fluke, Fasciola hepatica, as reflected by the 723 samples in the database of the National Freshwater Snail Collection, Potchefstroom, South Africa. The 221 different loci (1/16-degree squares) on record reflect an extensive but discontinuous distribution, except in Lesotho and in parts of the Mpumalanga, Gauteng and North West provinces of South Africa. Although recorded from 12 different types of waterbody, it was mostly (42.0%) recovered from swamps. Most samples (45.8%) were collected in habitats with slow-flowing water. A muddy substratum was recorded for 62.5% of the samples. Most samples (86.3%) were collected in habitats with a mean annual air temperature of 10-20 degrees C, and more than 69% came from localities with a mean annual rainfall of 600-900 mm. An integrated decision tree constructed from the data indicated that temperature and types of waterbody play a decisive role in determining the presence of L. truncatula in a given area. A temperature index calculated for all mollusc species ranked L. truncatula second in a total of 53 species according to its association with low temperatures. It remains to be established whether its distribution is indeed discontinuous, and whether its preference for a particular habitat, amphibious habits and ability to aestivate could have resulted in some populations having been overlooked during surveys.

  3. Characterization of the molluscicidal activity of Bauhinia variegata and Mimusops elengi plant extracts against the fasciola vector Lymnaea acuminata.

    Science.gov (United States)

    Singh, Kanchan Lata; Singh, D K; Singh, Vinay Kumar

    2012-01-01

    The molluscicidal activity of Bauhinia variegata leaf and Mimusops elengi bark was studied against vector snail Lymnaea acuminata. The toxicity of both plants was time and concentration-dependent. Among organic extracts, ethanol extracts of both plants were more toxic. Toxicity of B. variegata leaf ethanolic extract (96h LC50- 14.4 mg/L) was more pronounced than M. elengi bark ethanolic extract (96h LC50-15.0 mg/L). The 24h LC50 of column purified fraction of B. variegata and M. elengi bark were 20.3 mg/L and 18.3 mg/L, respectively. Saponin and quercetin were characterized and identified as active molluscicidal component. Co-migration of saponin (Rf 0.48) and quercetin (Rf 0.52) with column purified bark of M. elengi and leaf of B. variegata on thin layer chromatography demonstrate same Rf value i.e. 0.48 and 0.52, respectively. The present study clearly indicates the possibility of using M. elengi and/or B. variegata as potent molluscicide.

  4. A comparative study of haemocytes from resistant and susceptible Lymnaea natalensis snails exposed to Fasciola gigantica miracidia.

    Science.gov (United States)

    El-Sayed, Kamelia A; El-Din, Abdel-hakim saad; Gad EL-KAarim, Rasha M

    2014-12-01

    Effect ot infection with Fasciola gigantica on total and differential haemocytes count of resistant and susceptible Lymnaea natalensis snails were studied. Exposure of L. natalensis resistant and susceptible strains to F. gigantica on miracidia caused gradual increase in the number of circulating haemocytes at the same time of exposure. In susceptible strain, the increase in the number of circulating haemocytes became significant at the second week post exposure being 2560 cell/ml (p

  5. The stress of Lymnaea truncatula just before miracidial exposure with Fasciola hepatica increased the prevalence of infection.

    Science.gov (United States)

    Abrous, M; Rondelaud, D; Dreyfuss, G

    2001-09-01

    Single-miracidium infections of Lymnaea truncatula with Fasciola hepatica were carried out under laboratory conditions to determine whether the stress of snails just before miracidial exposure had any influence on the prevalence of Fasciola infection, redial burden, and cercarial shedding. Three methods, i.e., the fasting of L. truncatula for 3 days in water filtered through a Millipore membrane, the effect of 6-8 degrees C water for 15 min, or the immersion of L. truncatula in a detergent solution at low concentration for 15 min, were used to stress snails. Enhanced susceptibility of snails to F. hepatica infection was noted in stressed groups (93-96% vs 48-50% in controls). The number of free rediae did not show any variation in controls as well as in stressed groups, except for fasted snails in which free rediae were significantly fewer. No differences in cercarial production between controls and the cold group were noted. Fasting, cold shock, or detergent exposure prior to exposure to F. hepatica miracidia might have weakened the snails so that they were not as efficient in avoiding miracidial penetration, thus leading to higher infection rates. Copyright 2001 Academic Press.

  6. Aspects of the maintenance of the life cycle of Fasciola hepatica in Lymnaea columella in Minas Gerais, Brazil.

    Science.gov (United States)

    de Souza, Cecília Pereira; Magalhaes, Kelly Grace; Passos, Liana Konovaloff Jannotti; Pereira dos Santos, Glaucia Cristina; Ribeiro, Fabio; Katz, Naftale

    2002-04-01

    Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0% respectively. Over 15,806 metacercariae were obtained and stored at 4 degrees C. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days.

  7. Characterization of the molluscicidal activity of Bauhinia variegata and Mimusops elengi plant extracts against the fasciola vector lymnaea acuminata

    Directory of Open Access Journals (Sweden)

    Kanchan Lata Singh

    2012-06-01

    Full Text Available The molluscicidal activity of Bauhinia variegata leaf and Mimusops elengi bark was studied against vector snail Lymnaea acuminata. The toxicity of both plants was time and concentration-dependent. Among organic extracts, ethanol extracts of both plants were more toxic. Toxicity of B. variegata leaf ethanolic extract (96h LC50- 14.4 mg/L was more pronounced than M. elengi bark ethanolic extract (96h LC50-15.0 mg/L. The 24h LC50 of column purified fraction of B. variegata and M. elengi bark were 20.3 mg/L and 18.3 mg/L, respectively. Saponin and quercetin were characterized and identified as active molluscicidal component. Co-migration of saponin (Rf 0.48 and quercetin (Rf 0.52 with column purified bark of M. elengi and leaf of B. variegata on thin layer chromatography demonstrate same Rf value i.e. 0.48 and 0.52, respectively. The present study clearly indicates the possibility of using M. elengi and/or B. variegata as potent molluscicide.

  8. Distribution and habitats of the snail Lymnaea truncatula, intermediate host of the liver fluke Fasciola hepatica, in South Africa

    Directory of Open Access Journals (Sweden)

    K.N. de Kock

    2003-07-01

    Full Text Available This paper focuses on the geographical distribution and habitats of Lymnaea truncatula, the intermediate, snail host of the liver fluke, Fasciola hepatica, as reflected by the 723 samples in the database of the National Freshwater Snail Collection, Potchefstroom, South Africa. The 221 different loci (1/16-degree squares on record reflect an extensive but discontinuous distribution, except in Lesotho and in parts of the Mpumalanga, Gauteng and North West provinces of South Africa. Although recorded from 12 different types of waterbody, it was mostly (42.0 % recovered from swamps. Most samples (45.8 % were collected in habitats with slow-flowing water. A muddy substratum was recorded for 62.5 % of the samples. Most samples (86.3 % were collected in habitats with a mean annual air temperature of 10-20 o C, and more than 69 % came from localities with a mean annual rainfall of 600-900mm. An integrated decision tree constructed from the data indicated that temperature and types of waterbody play a decisive role in determining the presence of L. truncatula in a given area. A temperature index calculated for all mollusc species ranked L. truncatula second in a total of 53 species according to its association with low temperatures. It remains to be established whether its distribution is indeed discontinuous, and whether its preference for a particular habitat, amphibious habits and ability to aestivate could have resulted in some populations having been overlooked during surveys.

  9. Microhabitat preferences of Biomphalaria pfeifferi and Lymnaea natalensis in a natural and a man-made habitat in Southeastern Tanzania

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    Utzinger Jürg

    2000-01-01

    Full Text Available Schistosoma mansoni is an important human parasitic disease which is widespread throughout Africa. As Biomphalaria pfeifferi snails act as intermediate host, knowledge of their population ecology is an essential prerequisite towards understanding disease transmission. We conducted a field study and assessed the density and microhabitat preferences of B.pfeifferi in a natural habitat which was a residual pool of a river. Repeated removal collecting revealed a density of 26.6 [95% confidence interval (CI: 24.9-28.3] snails/m2. B.pfeifferi showed microhabitat preferences for shallow water (depths: 0-4cm. They were found most abundantly close to the shoreline (distances: 0-40cm, and preferred either plant detritus or bedrock as substratum. Lymnaea natalensis, a snail which may act as a host for human Fasciola gigantica, also occurred in this habitat with a density of 34.0 (95% CI: 24.7-43.3 snails/m2, and preferred significantly different microhabitats when compared to B.pfeifferi. Microhabitat selection by these snail species was also investigated in a man-made habitat nearby, which consisted of a flat layer of concrete fixed on the riverbed, covered by algae. Here, B.pfeifferi showed no preference for locations close to the shoreline, probably because the habitat had a uniform depth. We conclude that repeated removal collecting in shallow habitats provides reliable estimates of snail densities and that habitat changes through constructions may create favourable microhabitats and contribute to additional disease transmission.

  10. Behavioral Responses of the Snail Lymnaea acuminata towards Photo and Chemo Attractants: A New Step in Control Program of Fasciolosis

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    Anupam Pati Tripathi

    2013-01-01

    Full Text Available Fasciolosis is water and food borne disease, caused by Fasciola hepatica and F. gigantica. Snail Lymnaea acuminata is an intermediate host of these flukes. Snail control is one of the major methods to reduce the incidences of fasciolosis. Trapping of snails with the help of photo- and chemoattractants for treatment purposes will be a new tool in control program of fasciolosis. The present study shows that maximum numbers of snails were attracted (52 to 60%, when exposed to photo- and chemostimulant simultaneously, rather than when only chemo- (control (18 to 24% or photo- (control (14 to 19% stimulus was given. Maximum change in AChE activity in nervous tissue was observed when red monochromatic light was used (258.37% of white light control as opposed to blue (243.44% of white light control and orange (230.37% of white light control. The exposure of light directly stimulated the photoreceptors in eye which transmit the signals through nerves to the brain and snail response accordingly. In this signal transmission AChE is one of the important enzymes involved in this process.

  11. Distribution and habitats of Lymnaea natalensis, snail intermediate host of the liver fluke Fasciola gigantica, in South Africa

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    Editorial Office

    2001-09-01

    Full Text Available This paper focuses on the geographical distribution and the habitats of Lymnaea natalensis, the snail intermediate host of the liver fluke, Fasciola gigantica, as reflected by the collection sites of its 4 552 samples currently on record in the National Freshwater Snail Collection (NFSC of South Africa. Although this species was represented in a variety of waterbodies, the majority of samples(±70%came from rivers, brooks and dams and in 70.8% of the cases the water was described as permanent and in 71.8% as slow flowing or standing. The results of life-table studies conducted by various authors indicated that temperature should be a relatively unimportant factor in determining its geographical distribution, but that the availability of permanent water should be decisive for its presence in a given habitat. These results are in agreement with the finding that only 7.5% of the samples of this species in the NFSC were collected in habitats which were described as seasonal. Furthermore, it gives a logical explanation for the sporadic occurrence, or total absence of this species in the more arid regions of South Africa. Water impoundments and irrigation networks contribute to a large extent towards creating perennial habitats which would be suitable for L. natalensis. As intermediate host for one of the liver fluke species which already is an economic factor in South Africa, this certainly is an aspect which ought to be reckoned within the planning and construction of new irrigation schemes.

  12. Exposure to Fasciola hepatica miracidia increases the sensitivity of Lymnaea (Fossaria) humilis to high and low pH.

    Science.gov (United States)

    Cruz-Mendoza, I; Naranjo-García, E; Quintero-Martínez, M T; Ibarra-Velarde, F; Correa, D

    2006-06-01

    Humidity and temperature have been considered important factors affecting the infectivity of Fasciola hepatica to its molluscan host. One hundred and thirty laboratory-reared Lymnaea humilis were exposed for 4 hr to the miracidia of F. hepatica over a pH range from 4.0 to 10.0, and their rates of survival were compared with 130 similarly treated but unexposed control snails. All control snails died within 24 hr at pH 4.0, but they showed better survival at pH 5.0-10.0. Their sensitivity to solutions with high and low pH, however, was increased if kept in the presence of F. hepatica miracidia. Snails exposed at pH 5.0 died within 24 hr, whereas most other pHs also affected survival such that by day 18 only those snails exposed at pH 7.2 remained alive. The increased sensitivity of the snails to pH could be explained by a damage-mediated release of parasite enzymes, because infectivity was highest at pHs associated with the lowest host mortality.

  13. Adaptation of Lymnaea fuscus and Radix balthica to Fasciola hepatica through the experimental infection of several successive snail generations

    Science.gov (United States)

    2014-01-01

    Background High prevalence of Fasciola hepatica infection (>70%) was noted during several outbreaks before the 2000s in several French farms where Galba truncatula is lacking. Other lymnaeids such as Lymnaea fuscus, L. glabra and/or Radix balthica are living in meadows around these farms but only juvenile snails can sustain complete larval development of F. hepatica while older snails were resistant. The low prevalence of infection (hepatica infection in snails progressively increased from the F1 (R. balthica) or F2 (L. fuscus) generation. In the second experiment, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. fuscus and R. balthica (without significant differences between both lymnaeids) than in G. truncatula. Conclusion The F. hepatica infection of several successive snail generations, coming from parents infected with this parasite, resulted in a progressive increase in prevalence and intensity of snail infection. This may explain high prevalence of fasciolosis noted in several cattle-breeding farms when the common snail host of this digenean, G. truncatula, is lacking. PMID:24986589

  14. Hemocyte-specific responses to the peroxidizing herbicide fomesafen in the pond snail Lymnaea stagnalis (Gastropoda, Pulmonata)

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Jacqueline [UMR 6553 Ecobio CNRS Universite de Rennes 1, Campus de Beaulieu, F-35042 Rennes cedex 35042 (France); Lefeuvre-Orfila, Luz [UMR 985 INRA-Agrocampus Ecobiologie et Qualite des Hydrosystemes Continentaux, Equipe Ecotoxicologie et Qualite des Milieux aquatiques, 65 rue de Saint-Brieuc CS 84215, F-35042 Rennes cedex 35042 (France); Lagadic, Laurent [UMR 985 INRA-Agrocampus Ecobiologie et Qualite des Hydrosystemes Continentaux, Equipe Ecotoxicologie et Qualite des Milieux aquatiques, 65 rue de Saint-Brieuc CS 84215, F-35042 Rennes cedex 35042 (France)]. E-mail: laurent.lagadic@rennes.inra.fr

    2007-03-15

    Responses of circulating hemocytes were studied in Lymnaea stagnalis exposed to 10, 30, 90, and 270 {mu}g/L fomesafen for 24 and 504 h. Flow cytometry was used to quantify fomesafen-induced production of reactive oxygen species (ROS), phagocytic activity on Escherichia coli, and oxidative burst when hemocytes were challenged by E. coli or phorbol 12-myristate-13-acetate (PMA). Lysosomal membrane damage was assessed, using the neutral-red retention time (NRRT) assay. Exposure to fomesafen for 24 h resulted in increase in ROS levels and decreases in phagocytosis and the oxidative burst in PMA-stimulated hemocytes. After 504 h, intracellular levels of ROS returned to normal, but phagocytosis of E. coli was still inhibited and the associated oxidative burst significantly reduced. After both durations of exposure, decreases of NRRT indicated that lysosome membrane fragility increased with fomesafen concentration. Potential implications for the health and survival of the snails and consequences on populations are discussed. - Fomesafen inhibited phagocytosis and the associated oxidative burst, and increased lysosome fragility in L. stagnalis hemocytes.

  15. Feeding of Bait to Snail Lymnaea acuminata and Their Effect on Certain Enzyme in the Nervous Tissue.

    Science.gov (United States)

    Kumar, Pradeep; Singh, V K; Singh, D K

    2012-01-01

    Fascioliasis, a snail-borne parasitic zoonosis, has been recognized for a long time because of its major veterinary and human impact. Different Bait formulations were fed to the snail Lymnaea acuminata in clear glass aquaria having diameter of 30 cm. Snail attractant containing bait formulations was prepared from different binary combination (1 : 1 ratio) of carbohydrates (glucose, starch 10 mM) and amino acid (methionine, histidine 10 mM) in 100 ml of 2% agar solution + sublethal (20% and 60% of 24 h and 96 h LC50) doses of different molluscicides (eugenol, ferulic acid, umbelliferone, and limonene). Snails fed on bait containing sub-lethal concentration of different molluscicides and the snail attractant, causing a significant inhibition in alkaline phosphatase (ALP) and acetylcholinesterase (AChE) activity in the nervous tissue of the vector snail L. acuminata. Maximum inhibition in ALP (20% of control) and AChE (49.49% of control) activity was observed in the nervous tissue of the L. acuminata exposed to 60% of 96 h LC50 of eugenol in the bait pellets containing starch + histidine, starch + methionine, respectively.

  16. Aspects of the Maintenance of the Life Cycle of Fasciola hepatica in Lymnaea columella in Minas Gerais, Brazil

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    Souza Cecília Pereira de

    2002-01-01

    Full Text Available Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0% respectively. Over 15,806 metacercariae were obtained and stored at 4ºC. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days.

  17. Conceptual shifts in animal systematics as reflected in the taxonomic history of a common aquatic snail species (Lymnaea stagnalis

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    Maxim V. Vinarski

    2015-07-01

    Full Text Available Lymnaea stagnalis (L., 1758 is among the most widespread and well-studied species of freshwater Mollusca of the northern hemisphere. It is also notoriously known for its huge conchological variability. The history of scientific exploration of this species may be traced back to the end of the 16th century (Ulisse Aldrovandi in Renaissance Italy and, thus, L. stagnalis has been chosen as a proper model taxon to demonstrate how changes in theoretical foundations and methodology of animal taxonomy have been reflected in the practice of classification of a particular taxon, especially on the intraspecific level. In this paper, I depict the long story of recognition of L. stagnalis by naturalists and biologists since the 16th century up to the present day. It is shown that different taxonomic philosophies (essentialism, population thinking, tree thinking led to different views on the species’ internal structure and its systematic position itself. The problem of how to deal with intraspecific variability in the taxonomic arrangement of L. stagnalis has been a central problem that made systematists change their opinion following conceptual shifts in taxonomic theory.

  18. Two Strains of Lymnaea stagnalis and the Progeny from Their Mating Display Differential Memory-Forming Ability on Associative Learning Tasks

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    Hiroshi Sunada

    2017-09-01

    Full Text Available The pond snail Lymnaea stagnalis learns and forms long-term memory (LTM following both operant conditioning of aerial respiratory behavior and classical conditioning of taste aversive behavior. In the present study, we examined whether there are interstrain differences in the ability to form LTM following these two types of conditioning. A strain of Lymnaea (TC1 collected in Alberta, Canada exhibits superior memory-forming ability following aerial respiratory operant conditioning compared to a laboratory-reared strain of Lymnaea from Netherlands known as the Dutch strain. We asked whether the offspring of the Canadian TC1 and Dutch snails (i.e., filial 1 (F1 cross snails would have the superior memory ability and found, rather, that their memory ability was average like the Dutch snails. That is, the Canadian TC1 snails have superior ability for LTM formation following aerial respiratory operant conditioning, but the Dutch and the generated F1 cross have average ability for memory forming. We next examined the Canadian TC1, Dutch and F1 cross snails for their ability to learn and form memory following conditioned taste aversion (CTA. All three populations showed similar associative CTA responses. However, both LTM formation and the ratio of good-to-poor performers in the memory retention test were much better in the Dutch snails than the Canadian TC1 and F1 cross snails. The memory abilities of the Canadian TC1 and F1 cross snails were average. Our present findings, therefore, suggest that snails of different strains have different memory abilities, and the F1 cross snails do not inherit the memory ability from the smart strain. To our knowledge, there have been a limited number of studies examining differences in memory ability among invertebrate strains, with the exception of studies using mutant flies.

  19. Southernmost finding of Lymnaea viatrix orbigny, 1835 (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica (Linnaeus, 1758) (Trematoda: Digenea), in urban and rural areas of Patagonia, Argentina.

    Science.gov (United States)

    Kleiman, Florencia; Pietrokovsky, Silvia; Paraense, W Lobato; Wisnivesky-Colli, Cristina

    2004-02-01

    We report the first finding of Lymnaea viatrix south of parallel 41 masculine S, in rural and urban areas from Argentina. Ninety snails were collected during year 2000, from a concrete pond at a Public Square in El Bolsón Village, Río Negro province, and 811 snails in November 1999, and during 2000 from waterbodies within a farm at Cholila locality, Chubut province. Fasciola hepatica infection was detected in 0.9% snails from the rural area. We discuss the potential risk of L. viatrix to public health in urban areas and its epidemiological importance in rural areas of the Andean Patagonian region.

  20. Southernmost finding of Lymnaea viatrix orbigny, 1835 (Pulmonata: Lymnaeidae, intermediate host of Fasciola hepatica (Linnaeus, 1758 (Trematoda: Digenea, in urban and rural areas of Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Kleiman Florencia

    2004-01-01

    Full Text Available We report the first finding of Lymnaea viatrix south of parallel 41ºS, in rural and urban areas from Argentina. Ninety snails were collected during year 2000, from a concrete pond at a Public Square in El Bolsón Village, Río Negro province, and 811 snails in November 1999, and during 2000 from waterbodies within a farm at Cholila locality, Chubut province. Fasciola hepatica infection was detected in 0.9% snails from the rural area. We discuss the potential risk of L. viatrix to public health in urban areas and its epidemiological importance in rural areas of the Andean Patagonian region.

  1. Moluscos fluviales con importancia médico-veterinaria de la provincia Sancti Spíritus, región central de Cuba - Freshwater molluscs with medical-veterinarian importance in he province of Sancti Spiritus, central region of Cuba

    Directory of Open Access Journals (Sweden)

    Cruz Pineda, Carlos A

    2012-05-01

    Full Text Available ResumenLos moluscos dulceacuícolas han logrado desarrollar interesantes modificaciones con un alto balance adaptativo, radicando la importancia médico-veterinaria en las diversas enfermedades que varias especies le transmiten al hombre y a los animales.AbstractThe freshwater molluscs have developed interesting modifications with a high adaptation value, being the medical-veterinarian importance in the diverse illnesses that several species can transmit to human and animals.

  2. Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

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    José Ángel Bautista Cotorruelo

    2008-12-01

    Full Text Available The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de la Región de Murcia a telephone call from the Epidemiology Service, which reported the existence of about 12-15 cases of children affected by Molluscum contagiosum. In addition, they indicated us that the suspicions fell on the Municipal Pool Cover Alhama de Murcia. Immediately we contacted the responsible staff and we send them a protocol developed with information from several sources. The analysis of articles used for water activities showed absence of Molluscum contagiosum. We selected "absence of molds and yeasts” as indicator. All this coincided with the disappearance of the cases. Months later, in March 2009 we detected new cases of children affected in another pool in the town of Alcantarilla. Due to the success of the methodology used in the earlier incident we performed the same actions and we obtained the same results. The protocol developed by this Service is effective to avoid the occurrence of more cases. We propose the “absence of molds and yeasts” as an indicator to evaluate the presence of Molluscum contagiosum. Coinciding with the update of the rules of public swimming pools in our Region we have introduced an article that indicates that the objects used for water activities must be disinfected after each use.El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso

  3. Effects of copper on the egg development and hatching of a freshwater pulmonate snail Lymnaea luteola L.

    Science.gov (United States)

    Khangarot, B S; Das, Sangita

    2010-07-15

    A freshwater invertebrate egg development and hatching toxicity test with an Indian freshwater pulmonate snail, Lymnaea luteola, comprising the following developmental endpoints was described: mortality, development, formation of eyes and foot structure, heart rate, duration of different larval stages, and hatching time. Developmental stages were morula, and at third, fifth, and eighth days; the trochophore, veliger, and hippo larvae, respectively. At the age of about 9th to 11th days after egg laying; more than 95% young snail hatched in control laboratory conditions. To evaluate effects on embryonic development, the pulmonate snail eggs of 24-h old were exposed to a series of nominal copper concentrations. The percentage survival of embryos treated in 10-32 microg l(-1) of Cu after 240 h of exposure drops sharply at veliger and hippo stages. All embryos died at 100-320 microg l(-1) of Cu within 168 h of exposure at trochophore and early veliger stages. The detected abnormalities were malformation of foot, eyes, thinness and incomplete formation of shell, growth retardation, and slow rotation of embryo within the egg capsule as compared to control embryos. Lethal and sublethal effects in terms of mortality and significant delay in hatching could be found in the 3.2, 5.6 and 10 microg l(-1) of Cu concentrations. This species is widely distributed in the Indian subcontinent freshwater reservoirs and more sensitive to Cu than other tested aquatic test organisms; therefore, could be used as a test model of Cu and possibly other pollutants for rapid risk assessment of environmental pollutants. The snail egg embryo bioassay is simple, rapid, highly sensitive, cost-effective, and easy to test under standardized laboratory conditions.

  4. Proteomic Analysis of the Reproductive Organs of the Hermaphroditic Gastropod Lymnaea stagnalis Exposed to Different Endocrine Disrupting Chemicals

    Science.gov (United States)

    Giusti, Arnaud; Leprince, Pierre; Mazzucchelli, Gabriel; Thomé, Jean-Pierre; Lagadic, Laurent; Ducrot, Virginie; Joaquim-Justo, Célia

    2013-01-01

    Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD). In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin) could constitute relevant

  5. Proteomic analysis of the reproductive organs of the hermaphroditic gastropod Lymnaea stagnalis exposed to different endocrine disrupting chemicals.

    Directory of Open Access Journals (Sweden)

    Arnaud Giusti

    Full Text Available Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range of endocrine disrupting chemicals (EDCs. However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD. In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin could

  6. Nonylphenol polyethoxylate adjuvant mitigates the reproductive toxicity of fomesafen on the freshwater snail Lymnaea stagnalis in outdoor experimental ponds.

    Science.gov (United States)

    Jumel, Audrey; Coutellec, Marie-Agnès; Cravedi, Jean-Pierre; Lagadic, Laurent

    2002-09-01

    The influence of nonylphenol polyethoxylates (NPEO), formulated as the adjuvant Agral 90, on the effects of the diphenyl ether herbicide fomesafen in the pond snail Lymnaea stagnalis was investigated, with particular attention to the reproductive performances and underlying energetic and hormonal processes. Separate short-term exposures to low concentrations of fomesafen and fomesafen-Agral mixture were performed in the laboratory. Outdoor experimental ponds (mesocosms) were used for long-term exposures to higher chemical concentrations. At the concentrations used in the studies, NPEO were known as nontoxic in L stagnalis. Fomesafen was mixed with the adjuvant in the 3:7 ratio recommended for agricultural uses (nominal herbicide concentrations of 22 and 40 microg/L in laboratory and mesocosm, respectively). In mesocosms, multiple application of fomesafen, leading to maximal herbicide concentrations of 60.33 +/- 2.68 microg/L in water, resulted in reduced number of egg masses and altered glycogen metabolism in contaminated snails. These changes, as well as affected steroid-like levels in fomesafen-exposed snails, support the hypothesis of impaired neuroendocrine functions. When Agral 90 was added to the herbicide, results obtained in mesocosms showed that the adjuvant softened the impact of fomesafen. In mesocosms treated with the fomesafen-Agral mixture, significantly lower herbicide levels were found in the water (30.33 +/- 14.91 microg/L at the end of the contamination period). Consequently, internal exposure of the snails to fomesafen was reduced when the herbicide was mixed with the adjuvant. Mitigation of the effects of fomesafen by the adjuvant may therefore result from nonionic surfactant activity of NPEO that prevented fomesafen from reaching the snails.

  7. Fasciola gigantica: cercarial shedding pattern from Lymnaea natalensis after long-term exposure to cadmium at different temperatures.

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    Soliman, Maha F M

    2009-04-01

    Little is known about the response of Fasciola spp., inside its snail host to pollutant toxicity. The effect of long-term exposure of Lymnaea natalensis to 0.1 microg/l, 10 microg/l, or 100 microg/l cadmium (Cd) on the infection rates with F. gigantica, percentage of cercariae-shedding snails and cercariae shedding pattern was investigated. The snails were exposed to Cd for 7 days either pre-infection with single Fasciola miracidium or during the late pre-patent period of the infection. The possible interaction between metal exposure and acclimatization temperature was also studied in three ranges; 16-18 degrees C, 23-25 degrees C and 30-32 degrees C. Results clearly showed that host exposure to 100 microg/l Cd significantly affected the pattern of Fasciola development inside its snail host, and that the acclimatization temperature was a key factor affecting the role played by Cd. Pre-infection exposure to Cd caused a significant reduction in the infection rates where the effect was temperature-dependent. Post-infection exposure to Cd significantly increased the percentage of cercariae-shedding snails; the effect was temperature-independent. Interestingly, post-infection exposure significantly altered the differential cercarial output pattern, while no clear impact on the total was found. The alteration in the differential cercarial output was represented as a significantly higher proportion of floating metacercaria as compared to fixed ones and also higher proportion of dead cercariae which may directly reduce the transmission of Fasciola to the final host. The mechanisms of cadmium impact are briefly discussed.

  8. Highland populations of Lymnaea truncatula infected with Fasciola hepatica survive longer under experimental conditions than lowland ones.

    Science.gov (United States)

    Vignoles, P; Favennec, L; Dreyfuss, G; Rondelaud, D

    2002-04-01

    A retrospective study was carried out on the experimental infections of Lymnaea truncatula with Fasciola hepatica performed over the last 20 years to determine if the populations of snails living in highland or lowland countries had the same ability to sustain trematode larval development. The six highland populations originated from the Peruvian Altiplano (altitude 2,800 m), the French Alps (2,300 m), and the Massif Central (900-1,400 m), whereas the 13 lowland populations came from different sites located in central France (90-250 m). Bimiracidial infections of 4-mm-high snails were performed to study cercarial shedding and to quantify their redial burden. Compared to lowland populations, snail survival at day 30 post-exposure was significantly higher in the highland L. truncatula (57-75% compared to 31-45%) and their lifespan was greater (a mean of 87-96 days for cercaria-shedding snails compared to 64-77 days). The prevalences of F. hepatica infections, the numbers of free rediae within snail bodies, and the numbers of cercariae did not show any significant differences between highland and lowland snails although the numbers of cercariae were clearly higher in the Peruvian and three French highland populations of L. truncatula. The long survival times of highland snails under laboratory conditions might be an adaptation of these L. truncatula to the more extreme highland climate. The better ability of highland snails to sustain parasite larval development suggests that they would be better intermediate hosts in the life cycle of F. hepatica than lowland populations.

  9. Combination of molluscicides with attractant carbohydrates and amino acids in bait formulation against the snail Lymnaea acuminata.

    Science.gov (United States)

    Kumar, P; Singh, V K; Singh, D K

    2011-05-01

    Fascioliasis is an important helminth disease caused by Fasciola (F.) hepatica and F gigantica of Asia and Africa. This disease belongs to the plant-borne trematode zoonoses. Human infection has been reported in 51 different countries from 5 continents. One of the possible approaches to control this problem is to interrupt the life cycle of the parasitic trematodes by eliminating the snail. Snails attractant pellets (SAP) were prepared from binary combination of carbohydrate + amino acid (20 mM) in 2% agar solution with active molluscicidal component Ferula asafoetida (ferulic acid, umbelliferone), Syzygium aromaticum (eugenol), Carum carvi (limonene). Attraction of snails to different combinations was studied by using clear glass aquaria having diameter of 30 cm. Each aquarium was divided into four concentric zones; zone-3 (central zone), zone-2 and zone-1 (middie zone) and zone-0 (outer zone) had a diameter of 13, 18, 24, and 30 cm, respectively. The behavioral responses of snails to these binary combinations of carbohydrate and amino acid in bait formulation were examined. The fraction of snails that was in contact with the SAP at different times was used as a measure of attraction. Among all the binary combination of carbohydrate+amino acid+molluscicide after 2h of experiment, highest attraction of snail (54.71%) was observed towards the SAP containing starch+histidine+limolene. Limonene+ starch+histidine containing SAP emerged as the strongest bait formulation (96h LC50 0.74%) against Lymnaea acuminata. The present study suggested that the molluscicides of plant origin could be used with varying degrees of success in bait formulation.

  10. Interactions between cyanobacteria and gastropods II. Impact of toxic Planktothrix agardhii on the life-history traits of Lymnaea stagnalis.

    Science.gov (United States)

    Lance, Emilie; Paty, Chrystelle; Bormans, Myriam; Brient, Luc; Gérard, Claudia

    2007-03-30

    Hepatotoxins are frequently produced by many cyanobacterial species. Microcystins (MCs) are the most frequent and widely studied hepatotoxins, with potentially hazardous repercussions on aquatic organisms. As a ubiquitous herbivore living in eutrophic freshwaters, the snail Lymnaea stagnalis (Gastropoda: Pulmonata) is particularly exposed to cyanobacteria. The toxic filamentous Planktothrix agardhii is common in temperate lakes and is therefore, a potential food resource for gastropods. In the first part of this study, we demonstrated the ingestion of toxic P. agardhii by L. stagnalis during a 5 weeks exposure, with concomitant accumulation of, on average, 60% of total MCs ingested. After 3 weeks of non-toxic food (lettuce), approximately 90% of MCs were eliminated from tissues. Here, we investigate the impact of toxic P. agardhii consumption on the life-history traits (survival, growth and fecundity), locomotion and the structure of digestive and genital glands of juvenile and adult L. stagnalis. We observed a decrease of growth regardless of age, although this was more marked in juveniles, and a reduction of fecundity in adults. Survival and locomotion were not affected. Reduction of growth and fecundity continued to be observed even after feeding of non-toxic food for 3 weeks. The structure of the digestive gland was altered during the intoxication period but not irreversibly as cells tended to recover a normal status after the 3-week detoxification period. No histopathological changes occurred in the genital gland and oocytes, and spermatozoids were present in the gonadic acini. The density of cyanobacterial suspensions used in this study was comparable to those regularly observed in lakes, particularly in eutrophic waters. These results are discussed in terms of the negative impact of toxic cyanobacteria on natural communities of freshwater gastropods, and potential cascading effects on the equilibrium and functioning of the ecosystem.

  11. Serotonin modulates transmitter release at central Lymnaea synapses through a G-protein-coupled and cAMP-mediated pathway.

    Science.gov (United States)

    McCamphill, P K; Dunn, T W; Syed, N I

    2008-04-01

    Neuromodulation is central to all nervous system function, although the precise mechanisms by which neurotransmitters affect synaptic efficacy between central neurons remain to be fully elucidated. In this study, we examined the neuromodulatory action of serotonin [5-hydroxytryptamine (5-HT)] at central synapses between identified neurons from the pond snail Lymnaea stagnalis. Using whole-cell voltage-clamp and sharp electrode recording, we show that 5-HT strongly depresses synaptic strength between cultured, cholinergic neuron visceral dorsal 4 (VD4 - presynaptic) and its serotonergic target left pedal dorsal 1 (LPeD1 - postsynaptic). This inhibition was accompanied by a reduction in synaptic depression, but had no effect on postsynaptic input resistance, indicating a presynaptic origin. In addition, serotonin inhibited the presynaptic calcium current (I(Ca)) on a similar time course as the change in synaptic transmission. Introduction of a non-condensable GDP analog, GDP-beta-S, through the presynaptic pipette inhibited the serotonin-mediated effect on I(Ca.) Similar results were obtained with a membrane-impermeable inactive cAMP analog, 8OH-cAMP. Furthermore, stimulation of the serotonergic postsynaptic cell also inhibited presynaptic currents, indicating the presence of a negative feedback loop between LPeD1 and VD4. Taken together, this study provides direct evidence for a negative feedback mechanism, whereby the activity of a presynaptic respiratory central pattern-generating neuron is regulated by its postsynaptic target cell. We demonstrate that either serotonin or LPeD1 activity-induced depression of presynaptic transmitter release from VD4 involves voltage-gated calcium channels and is mediated through a G-protein-coupled and cAMP-mediated system.

  12. Identification of a novel UDP-GalNAc:GlcNAcβ-R β1-4 N-acetylgalactosaminyltransferase from the albumen gland and connective tissue of the snail Lymnaea stagnalis

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Mulder, H.; Spronk, B.A.; Schachter, H.; Neeleman, A.P.; Eijnden, D.H. van den; Jong-Brink, M. de; Kamerling, J.P.

    1995-01-01

    Both the albumen gland, one of the female accessory sex glands, and connective tissue of the freshwater snail Lymnaea stagnalis contain N-acetylgalactosaminyltransferase activity, capable of transferring GalNAc from UDP-GalNAc in beta1-4 linkage to the terminal GlcNAc residue of GlcNAcbeta-R. The al

  13. Aptitude of Lymnaea palustris and L. stagnalis to Fasciola hepatica larval development through the infection of several successive generations of 4-mm-high snails.

    Science.gov (United States)

    Vignoles, P; Rondelaud, D; Dreyfuss, G

    2016-06-01

    Bimiracidial infections of Lymnaea palustris and Lymnaea stagnalis (shell height at exposure, 4 mm) with Fasciola hepatica were carried out during six successive snail generations to determine if prevalence and intensity of snail infection increased over time through descendants issuing from eggs laid by parents already exposed to this digenean. Controls were constituted by a French population of Galba truncatula (a single generation) infected according to the same protocol. In a first experiment performed with the F1 to F5 generations of L. palustris, the prevalence and intensity of F. hepatica infection in snails progressively increased. Immature rediae and a few cercariae-containing rediae of the digenean were observed in L. stagnalis from the F3 generation, but no free cercaria was noted in the bodies of this lymnaeid from the F4 to F6 generations. In another experiment carried out with the F6 generation of L. palustris, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. palustris than in G. truncatula. This mode of snail infection suggests an explanation for cases of human fasciolosis occurring in central France after the collection of wild watercress from beds where L. palustris was the sole lymnaeid.

  14. Verificação de antagonismo entre larvas de Schistosoma mansoni e larvas de outros Digenea em Biomphalaria tenagophila, molusco planobídeo de criadouro natural situado na região de Campinas, SP, Brasil Verification of the antagonism between larvae of Schistosoma mansoni and those of other Digenea in Biomphalaria tenagophila, a planorbid molusc from a natural breeding ground in the region of Campinas, SP, Brazil

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    Soely Maria Pissini Machado

    1988-12-01

    Full Text Available Foi observado o comportamento de larvas de S. mansoni em moluscos prévia e naturalmente infectados por larvas de outros Digenea. Foi verificado que as larvas de S. mansoni não se desenvolveram nos moluscos previamente infectados com purcocercárias longifurcadas com ocelos ou com furcocercárias longifurcadas sem ocelos. Observou-se resistência parcial ao desenvolvimento de S. mansoni nos moluscos previamente infectados por equinostomocercárias ou por distomocercárias com acúleo. A ausência de reação amebocitária em torno dos esporocistos de S. mansoni nos moluscos infectados por outros digenéticos parece indicar a não participação dos amebócitos na resistência oferecida ao desenvolvimento das larvas de S. mansoni.The objective of the present work is to study the development of S. mansoni larvae in snails found naturally infected by other digenetic trematode larvae. It was found that S. mansoni larvae did not develop in snails previoulsy infected by furcicercariae either with or without ocelli. Partial resistance to the development of S. mansoni was observed in snails previously infected by cercariae of Echinostomatidae or by cercariae with aculeus of Distomata. Absence of amoebocitary reaction around the S. mansoni sporocysts in snails previously infected by other digenetic trematodes indicates that amoebocytes did not play any role in the resistance mechanism.

  15. Native and non-indigenous boring polychaetes in Chile: a threat to native and commercial mollusc species Poliquetos perforadores nativos y no indígenas en Chile: una amenaza para moluscos nativos y comerciales

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    RODRIGO A MORENO

    2006-06-01

    Full Text Available Boring polychaetes infesting the shells of aquacultured molluscs affect host fitness and cause serious economic problems for the aquaculture industry. In Chile, knowledge of the native and non-indigenous polychaete fauna associated with mollusc hosts is limited, in spite of the fact that numerous native and non-indigenous mollusc species are actively harvested. We present the first complete list of boring polychaete species present in Chile, with a review of the information regarding each species' status as a native or non-indigenous species (NIS, together with information on native and introduced ranges, affected host species, likely vectors of introduction and donor areas. We recorded a total of nine boring polychaetes present along the Chilean coast including native and NIS. Within the NIS category we provide the first published report of the Sabellid Terebrasabella heterouncinata in South America. Boring polychaetes utilized both native and introduced host species. The finding of polychaete species which utilized multiple native and NIS hosts, indicates a potential risk for spread between aquaculture facilities and the natural environment. Our analysis suggests that aquaculture activities are probably the primary introduction vector for boring polychaete species to Chile and that this region does not differ in the magnitude of introduced boring polychaetes relative to other regions of the world. We discuss current laws and management regarding polychaete infestations and make recommendations for future management in Chile, which should contemplate a rational compromise between the socio-economic needs of the country and plans to protect and preserve the nation's biodiversityLa colonización de especies de poliquetos perforadores sobre conchas de moluscos de cultivos puede afectar la adecuación biológica del hospedador y causar serios problemas económicos para la industria acuícola. En Chile, el conocimiento de la fauna de poliquetos

  16. Padrões dermatoscópicos do molusco contagioso: estudo de 211 lesões confirmadas por exame histopatológico Dermoscopic patterns of molluscum contagiosum: a study of 211 lesions confirmed by histopathology

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    Mayra Ianhez

    2011-02-01

    Full Text Available FUNDAMENTOS: Embora de fácil diagnóstico, o molusco contagioso pode apresentar-se como lesões inflamadas, únicas ou pequenas de difícil diagnóstico. OBJETIVO: Descrever características dermatoscópicas do molusco contagioso e comparar achados do exame clínico e dermatoscópico. MÉTODOS: Avaliou-se clínica e dermatoscopicamente lesões confirmadas pela histopatologia em 57 pacientes. RESULTADOS: Nos exames clínico e dermatoscópico de 211 lesões, foram visualizados orifícios em 50,24% e 96,68% das lesões e vasos em 6,16% e 89,10% delas, respectivamente. Os padrões vasculares encontrados em 188 lesões que apresentaram vasos à dermatoscopia foram coroa (72,34%, radial (54,25% e puntiforme (20,21%. Metade das 188 lesões apresentou padrão vascular combinado, sendo o padrão em flor (novo padrão vascular responsável por 19,68%. Foram identificados mais orifícios e vasos no exame dermatoscópico que no clínico, inclusive naquelas com inflamação, eczema perilesional e de tamanho pequeno. Vasos puntiformes relacionaram-se com inflamação, escoriação e eczema perilesional. CONCLUSÕES: A dermatoscopia das lesões de molusco mostrou-se superior ao exame dermatológico mesmo quando seu diagnóstico clínico torna-se difícil. A presença de orifícios, vasos e padrões vasculares específicos auxilia no seu diagnóstico e na diferenciação de outras lesões de pele.BACKGROUNDS: Although easily diagnosed, molluscum contagiosum may present as a single lesion or as several small, inflamed lesions of difficult diagnosis. OBJECTIVE: To describe the dermoscopic characteristics of molluscum contagiosum and to compare the findings from clinical examination and dermoscopy. METHODS: Histopathologically confirmed lesions were evaluated clinically and dermoscopically in 57 patients. RESULTS: At clinical examination and dermoscopy of 211 lesions, orifices were visualized in 50.24% and 96.68% of the lesions, and vessels in 6.16% and 89

  17. Síntesis de los estudios sobre moluscos continentales neógenos del sector septentrional de la Depresión de Teruel: período 1775-1998

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    Robles, F.

    2006-12-01

    Full Text Available The relevant information on the fossil record of the Neogene molluscs of the north of the Teruel Basin in the period between the years 1775-1998 is compiled and analyzed. First, the total number of different taxa mentioned in every paper is counted, second only the number of specific references is counted. The last references are divided into three categories called: new references, new species and repeated references. Apart from the information contained in every paper, the number of taxa contemplated, and the typology of the specific references, it is proposed a classification of the studies on neogene molluscs of this area in six stages: first (1775-1849, second (1849-1910, third (1910-1936, fourth (1936-1962, fifth (1962-1991 and sixth (1991-1998.Se recopila y analiza la información que se considera más relevante y se encuentra contenida en los estudios realizados sobre el registro fósil de los moluscos neógenos del sector septentrional de la Depresión de Teruel en el período comprendido entre los años 1775 y 1998. Se contabilizan, por una parte, el número total de taxones diferentes mencionados en cada trabajo y, por otra, sólo el número de citas efectuadas a nivel de especie en cada uno de ellos. Estas últimas se organizan en tres categorías que reciben el nombre de citas nuevas, especies nuevas y citas repetidas. Se propone, a partir de la información contenida en cada trabajo, el número de taxones contemplados, y la tipología de sus citas específicas, una clasificación de los estudios sobre moluscos neógenos de esta área en seis etapas: primera (1775-1849, segunda (1849-1910, tercera (1910 1936, cuarta (1936-1962, quinta (1962-1991 y sexta (1991-1998.

  18. Composición, distribución y abundancia de larvas de moluscos gastrópodos en el sur de Quintana Roo, México y norte de Belice

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    J Oliva Rivera

    2000-12-01

    Full Text Available Para conocer la composición, abundancia y distribución de larvas de gastrópodos, se realizaron muestreos mensuales de abril a diciembre de 1996 en el sur de Quintana Roo, México y norte de Belice. Las recolectas se hicieron en seis sitios de Banco Chinchorro, cuatro de la costa sur y seis en Hol-Chan, Belice. Las recolectas fueron hechas entre las 10 y 20 hrs, se bombearon 2.5 m³ de agua de mar por recolecta en un tiempo de diez minutos, filtrando a los organismos en una malla de 202 µm. Se identificaron un total de 27 especies de moluscos, las especies de mayor abundancia y de más amplia distribución en cada zona fueron: en la costa sur Rissoina sp. 1, Limacina sp. 1 y Natica sp., en Banco Chinchorro, Limacina sp. 1, Creseis acicula, Cerithiopsis hero y Rissoina sp. 1 y en Hol-Chan, Limacina sp. 2, Alaba incerta y Rissoina sp. 1. En general la mayor abundancia de moluscos se presentó en la época de lluvias. Aparentemente la presencia de corrientes y vientos fuertes y otros factores biológicos como el alimento, controlan la distribución y abundancia de las larvas.ha.To know the composition, abundance and distribution of gastropod larvae, monthly samplings were carried out in the south of Quintana Roo, Mexico and north of Belize, from April to December, 1996. Collections were made in six sites at Chinchorro Bank, four in the South Coast and six at Hol-Chan, Belize, between the 10 and 20 hrs. At each station 2.5 m_ of seawater were pumped through a 202 µm mesh; 27 species were identified. The most abundant species were: South Coast, Rissoina sp. 1., Limacina sp. 1 and Natica sp. 1, Chinchorro Bank, Limacina sp. 1, Creseis acicula, Cerithiopsis hero and Rissoina sp.1 and Hol-Chan, Limacina sp.2, Alaba incerta and Rissoina sp.1. The highest abundance was in rainy season. Apparently the presence of winds, coastal currents and food availability, control the distribution and abundance of larvae.

  19. The effect of abiotic factors on the toxicity of cypermethrin against the snail Lymnaea acuminata in the control of fascioliasis.

    Science.gov (United States)

    Singh, V; Singh, D K

    2009-03-01

    Every month during the year 2006-2007, the 24, 48, 72 and 96 h LC50 values of a molluscicide, cypermethrin, were determined for a snail Lymnaea acuminata, with concomitant estimation of levels of temperature, pH, dissolved oxygen and carbon dioxide and electrical conductivity, both in control and test water. On the basis of a 24 h toxicity assay, it was noted that LC50 values of 10.39, 10.90 and 11.19 mg l- 1 during the months of May, June and July, respectively, were most effective in killing the snails, while the molluscicide was least effective in the month of January, when its 24 h LC50 was 65.84 mg l- 1.There was a significant positive correlation between LC50 of cypermethrin and levels of dissolved O2/pH of water in corresponding months. On the contrary, a negative correlation was observed between LC50 and dissolved CO2/temperature of test water in the same months. In order to ascertain that such a relationship between toxicity and abiotic factors is not coincidental, the nervous tissue of the snail was assayed for the activity of acetylcholinesterase (AChE), acid phosphatase (ACP) and alkaline phosphatase (ALP) to sublethal concentrations (40% and 80%) of 24 h LC50 during each of the 12 months of the same year. The findings confirmed that abiotic factors indeed influence toxicity of cypermethrin in the snail. A significant positive rank correlation between AChE, ACP and ALP activity did exist following exposure to the corresponding sublethal concentrations. Moreover, there was a maximum inhibition of 61.29 and 76.16% of AChE and ACP, respectively, in snails exposed to 80% of the 24 h LC50 in the month of May. A similar treatment caused a maximum inhibition of 70.53% of ALP activity in the month of June. This work shows conclusively that the best time to control the snail population with cypermethrin is during the months of May and June.

  20. Developmental toxicity of metaldehyde in the embryos of Lymnaea stagnalis (Gastropoda: Pulmonata) co-exposed to the synergist piperonyl butoxide.

    Science.gov (United States)

    Hallett, Katrina C; Atfield, Andrew; Comber, Sean; Hutchinson, Thomas H

    2016-02-01

    Metaldehyde is a widely used molluscicide in countries where damage to crops from slugs and snails is a major problem associated with warm and wet winters. In the UK it is estimated that over 8% of the area covered by arable crops is treated with formulated granular bait pellets containing metaldehyde as the main active ingredient. Metaldehyde is hydrophilic (log Kow=0.12), water soluble (200 mg·L(-1) at 17 °C) and has been detected in UK surface waters in the concentration range of typically 0.2-0.6 μg·L(-1) (maximum 2.7 μg·L(-1)) during 2008-2011. In the absence of chronic data on potential hazards to non-target freshwater molluscs, a laboratory study was conducted to investigate the impact of metaldehyde on embryo development in the gastropod Lymnaea stagnalis (RENILYS strain) and using zinc as a positive control. L. stagnalis embryos were exposed to metaldehyde under semi-static conditions at 20±1 °C and hatching success and growth (measured as shell height and intraocular distance) examined after 21 d. Exposure concentrations were verified using HPLC and gave 21 d (hatching)NOEC and (hatching)LOEC mean measured values of 36 and 116 mg MET·L(-1), respectively (equal to the 21 d (shell height)NOEC and (shell height)LOEC values). For basic research purposes, a second group of L. stagnalis embryos was co-exposed to metaldehyde and the pesticide synergist piperonyl butoxide (PBO). Co-exposure to the PBO (measured concentrations between 0.47-0.56 mg·L(-1)) reduced hatching success from 100% to 47% and resulted in a 30% reduction in embryo growth (shell height) in snail embryos co-exposed to metaldehyde at 34-36 mg·L(-1) over 21 d. In conclusion, these data suggest mollusc embryos may have some metabolic detoxication capacity for metaldehyde and further work is warranted to explore this aspect in order to support the recent initiative to include molluscs in the OECD test guideline programme.

  1. Fascioliasis transmission by Lymnaea neotropica confirmed by nuclear rDNA and mtDNA sequencing in Argentina.

    Science.gov (United States)

    Mera y Sierra, Roberto; Artigas, Patricio; Cuervo, Pablo; Deis, Erika; Sidoti, Laura; Mas-Coma, Santiago; Bargues, Maria Dolores

    2009-12-03

    Fascioliasis is widespread in livestock in Argentina. Among activities included in a long-term initiative to ascertain which are the fascioliasis areas of most concern, studies were performed in a recreational farm, including liver fluke infection in different domestic animal species, classification of the lymnaeid vector and verification of natural transmission of fascioliasis by identification of the intramolluscan trematode larval stages found in naturally infected snails. The high prevalences in the domestic animals appeared related to only one lymnaeid species present. Lymnaeid and trematode classification was verified by means of nuclear ribosomal DNA and mitochondrial DNA marker sequencing. Complete sequences of 18S rRNA gene and rDNA ITS-2 and ITS-1, and a fragment of the mtDNA cox1 gene demonstrate that the Argentinian lymnaeid belongs to the species Lymnaea neotropica. Redial larval stages found in a L. neotropica specimen were ascribed to Fasciola hepatica after analysis of the complete ITS-1 sequence. The finding of L. neotropica is the first of this lymnaeid species not only in Argentina but also in Southern Cone countries. The total absence of nucleotide differences between the sequences of specimens from Argentina and the specimens from the Peruvian type locality at the levels of rDNA 18S, ITS-2 and ITS-1, and the only one mutation at the mtDNA cox1 gene suggest a very recent spread. The ecological characteristics of this lymnaeid, living in small, superficial water collections frequented by livestock, suggest that it may be carried from one place to another by remaining in dried mud stuck to the feet of transported animals. The presence of L. neotropica adds pronounced complexity to the transmission and epidemiology of fascioliasis in Argentina, due to the great difficulties in distinguishing, by traditional malacological methods, between the three similar lymnaeid species of the controversial Galba/Fossaria group present in this country: L. viatrix

  2. Adaptation of Lymnaea fuscus and Radix balthica to Fasciola hepatica through the experimental infection of several successive snail generations.

    Science.gov (United States)

    Rondelaud, Daniel; Titi, Amal; Vignoles, Philippe; Mekroud, Abdeslam; Dreyfuss, Gilles

    2014-07-01

    High prevalence of Fasciola hepatica infection (>70%) was noted during several outbreaks before the 2000s in several French farms where Galba truncatula is lacking. Other lymnaeids such as Lymnaea fuscus, L. glabra and/or Radix balthica are living in meadows around these farms but only juvenile snails can sustain complete larval development of F. hepatica while older snails were resistant. The low prevalence of infection (<20%) and limited cercarial production (<50 cercariae per infected snail) noted with these juveniles could not explain the high values noted in these cattle herds. As paramphistomosis due to Calicophoron daubneyi was not still noted in these farms, the existence of another mode of infection was hypothesized. Experimental infection of several successive generations of L. glabra, originating from eggs laid by their parents already infected with this parasite resulted in a progressive increase in prevalence of snail infection and the number of shed cercariae. The aim of this paper was to determine if this mode of snail infection was specific to L. glabra, or it might occur in other lymnaeid species such as L. fuscus and R. balthica. Five successive generations of L. fuscus and R. balthica were subjected to individual bimiracidial infections in the laboratory. Resulting rediae and cercariae in the first four generations were counted after snail dissection at day 50 p.e. (20°C), while the dynamics of cercarial shedding was followed in the F5 generation. In the first experiment, prevalence and intensity of F. hepatica infection in snails progressively increased from the F1 (R. balthica) or F2 (L. fuscus) generation. In the second experiment, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. fuscus and R. balthica (without significant differences between both lymnaeids) than in G. truncatula. The F. hepatica infection of several successive snail generations, coming from parents infected with this

  3. Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

    Science.gov (United States)

    Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

    2014-12-01

    The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68

  4. An interactive map to assess the potential spread of Lymnaea truncatula and the free-living stages of Fasciola hepatica in Switzerland.

    Science.gov (United States)

    Rapsch, Christina; Dahinden, Tobias; Heinzmann, Dominik; Torgerson, Paul R; Braun, Ueli; Deplazes, Peter; Hurni, Lorenz; Bär, Hansruedi; Knubben-Schweizer, Gabi

    2008-07-04

    The intermediate host of Fasciola hepatica is Lymnaea truncatula in Switzerland. The snail and the free-living stages of the parasite require a moderate climate and moisture for survival, reproduction, and transmission. In Switzerland, these conditions are present in many regions, resulting in a mean prevalence of bovine fasciolosis from 8.4 to 21.4%. An interactive map was created in order to demonstrate the relative risk of transmission by modelling the environmental conditions that promote the survival and reproduction of the larval stages of the parasite and the parasite's intermediate host. The map is based on temperature and rainfall data, soil conditions including ground water and forest cover in Switzerland. Extensive information on the free-living stages of F. hepatica and the intermediate host L. truncatula and how the development of these are affected by these environmental factors was used to create the interactive risk map.

  5. Uptake and distribution of copper sulfate and its effect on the respiration rate of the hemocyanin-producing freshwater snail Lymnaea natalensis

    Energy Technology Data Exchange (ETDEWEB)

    Wolmarans, C.T.; Yssel, E.

    1988-08-01

    Copper sulfate was one of the earliest compounds suggested as a molluscicide and although several new compounds have since been developed, copper sulfate is still widely used against freshwater snail intermediate hosts of trematode parasites causing bilharzia. However, the toxic effect that copper sulfate may have on these species has not yet been investigated adequately. This incomplete picture of the action of copper sulfate on freshwater snails is further complicated by the fact that some of these snail species have hemocyanin (a protein containing copper) as respiration pigment. Because of the existence of a copper metabolic pathway, these species may handle external copper differently from those species with hemoglobin as respiration pigment. In the present study, the uptake of external copper in the form of copper sulfate, as well as the effect of this ion on respiration rate, was investigated in Lymnaea natalensis, the intermediate host of Fasciola gigantica. This snail possesses hemocyanin as respiratory pigment.

  6. [Lymnaea cousini , intermediate host of Fasciola hepatica in the Colombian high tropical Andes, and its new haplotypes confirmed with the mitochondrial marker cytochrome oxidase I].

    Science.gov (United States)

    Uribe, Nelson; Becerra, Wlda Margarita; Velásquez, Luz Elena

    2014-01-01

    Fasciolosis is the disease transmitted by vectors with the highest latitudinal, longitudinal, and altitudinal distribution due to the colonizing capacity of the parasite Fasciola hepatica and its intermediate hosts, Lymnaeidae mollusks. These snails are under research due to their epidemiological importance, but their taxonomic identification is difficult given their interspecific phenotypical similarity. For this reason, there is uncertainty regarding Lymnaea cousini -a host of F. hepatica in Colombia- due to the morphological similarity it has with Lymnaea meridensis , recently described for Venezuela. To confirm with the COI marker (ADNmt) the taxonomic status of individuals morphologically identified as L. cousini from Nariño, Norte de Santander, and Santander (Colombia), deposited in the Vector Mollusks Collection VHET No. 37 of Universidad de Antioquia. The amplification of the mitochondrial COI required total DNA extraction of each individual´s foot using the DNeasy Blood and Tissue Kit (Qiagen®). Products amplified were sent for sequencing to Macrogen Inc., Korea. Twenty seven sequences generated in this research were compared to sequences published in the GenBank, including sequences of the type locality of L. cousini . Two new haplotypes of L. cousini were obtained for Colombia. Specimens from Nariño correspond to haplotype A, referenced for Ecuador, and specimens from Santander and Norte de Santander belong to a new haplotype we called haplotype D. By using the mitochondrial COI marker, we confirmed that the species under study did correspond to L. cousini . The number of known haplotypes of the species for Colombia has been duplicated and its geographical distribution has been extended to the southwest and northeast of the Colombian high Andean region.

  7. DNA multigene characterization of Fasciola hepatica and Lymnaea neotropica and its fascioliasis transmission capacity in Uruguay, with historical correlation, human report review and infection risk analysis.

    Science.gov (United States)

    Bargues, María Dolores; Gayo, Valeria; Sanchis, Jaime; Artigas, Patricio; Khoubbane, Messaoud; Birriel, Soledad; Mas-Coma, Santiago

    2017-02-01

    Fascioliasis is a pathogenic disease transmitted by lymnaeid snails and recently emerging in humans, in part due to effects of climate changes, anthropogenic environment modifications, import/export and movements of livestock. South America is the continent presenting more human fascioliasis hyperendemic areas and the highest prevalences and intensities known. These scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks. A study including DNA marker sequencing of fasciolids and lymnaeids, an experimental study of the life cycle in Uruguay, and a review of human fascioliasis in Uruguay, are performed. The characterization of Fasciola hepatica from cattle and horses of Uruguay included the complete sequences of the ribosomal DNA ITS-2 and ITS-1 and mitochondrial DNA cox1 and nad1. ITS-2, ITS-1, partial cox1 and rDNA 16S gene of mtDNA were used for lymnaeids. Results indicated that vectors belong to Lymnaea neotropica instead of to Lymnaea viator, as always reported from Uruguay. The life cycle and transmission features of F. hepatica by L. neotropica of Uruguay were studied under standardized experimental conditions to enable a comparison with the transmission capacity of F. hepatica by Galba truncatula at very high altitude in Bolivia. On this baseline, we reviewed the 95 human fascioliasis cases reported in Uruguay and analyzed the risk of human infection in front of future climate change estimations. The correlation of fasciolid and lymnaeid haplotypes with historical data on the introduction and spread of livestock into Uruguay allowed to understand the molecular diversity detected. Although Uruguayan L. neotropica is a highly efficient vector, its transmission capacity is markedly lower than that of Bolivian G. truncatula. This allows to understand the transmission and epidemiological differences between Andean highlands and non

  8. Relação entre a patogenicidade do Schistosoma mansoni em camundongos e a susceptibilidade do molusco vetor: III. Mortalidade, pesos corporal e das vísceras Relationship between the pathogenicity of Schistosoma mansoni in mice and the susceptibility of the vector mollusc: III. Mortality, body weight and viscera weights

    Directory of Open Access Journals (Sweden)

    Eliana Maria Zanotti-Magalhães

    1995-08-01

    Full Text Available Estudou-se a relação entre o desenvolvimento da hepatomegalia, da esplenomegalia, peso corporal e taxa de mortalidade em camundongos experimentalmente infectados por Schistosoma mansoni com o grau de susceptibilidade de Biomphalaria glahrata e B. tenagophila nas quais se desenvolveram as cercárias infectantes respectivamente, das linhagens BH e SJ. Foram utilizados como hospedeiro definitivo camundongos Swiss, SPF e como hospedeiros intermediários populações de moluscos selecionados geneticamente para o caráter susceptibilidade. Foram observados menores pesos corporais e das visceras em camundongos infectados com cercárias provenientes de moluscos que apresentaram elevado grau de susceptibilidade. A maior susceptibilidade dos moluscos à infecção pelo S. mansoni correspondeu a uma menor sobrevivência dos camundongos infectados. Os resultados fazem crer que a maior adaptação do parasita ao hospedeiro intermediário, traduzidos pelas taxas mais elevadas de susceptibilidade, pode levar a um comportamento diferente deste parasita no hospedeiro definitivo.The relationship between the development of hepatomegaly, splenomegaly, body weight and mortality rate and the degree of susceptibility of Biomphalaria glabrata and B. tenagophila at which infective cercariae developed was studied. The study utilized Swiss mice, SPF, as definitive hosts and populations of snails genetically selected for character susceptibility as intermediate hosts. Low body weight and smaller viscera were observed in infected mice with cercariae originating from snails that showed a high degree of susceptibility. The higher susceptibility of molluscs infected with S. mansoni corresponded to a lower survival of the infected mice. These results lead to the conclusion that the higher degree of adaptation of the parasite to its intermediate hosts, evidenced by the high indexes of susceptibility, leads to different behaviour on the part of this parasite in its definitive

  9. Movilidad, redes de intercambio y circulación de bienes en el sudoeste del Neuquén (Norpatagonia, Argentina): Los moluscos marinos del lago Traful Mobility, Exchange Networks And Circulation Of Goods In Southwestern Neuquén, Northern Patagonia, Argentina: The Marine Mollusks From Traful Lake

    OpenAIRE

    Mario Silveira; Lisandro López; Guido Pastorino

    2010-01-01

    Se determina la procedencia de fragmentos de moluscos marinos hallados en los aleros Los Cipreses y Lariviere, en el área del lago Traful, sur de la provincia de Neuquén. Estudios previos en áreas cercanas con mayor proximidad a la costa del océano Pacífico suponen que las piezas recuperadas evidencian contacto con grupos provenientes del lado occidental de la cordillera de Los Andes -Chile. En este trabajo se indica que parte de las valvas estudiadas corresponden a fósiles marinos o fluviale...

  10. Observações adicionais sobre o sexo do "Schistosoma mansoni" nas infestações por cercarias de um unico molusco Further observations on the sex of "Schistosoma mansoni" in the infestations produced by cercariae from a single snail

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1949-12-01

    Full Text Available Em um córrego situado nos terrenos do Instituto Oswaldo Cruz, em Man¬guinhos, no qual existe uma população de Australorbis olivaceus, foi verificada a infestação natural dêste planorbídeo pelo Schistosoma mansoni, com o índice de 8.25% baseado na dissecção de 400 moluscos. As cercárias de 24 planorbídeos foram inoculadas em 24 cobaias, cada vertebrado recebendo as cercárias de um único molusco. Uma segunda série de inoculações em 6 cobaias foi feita com as cercárias de 6 planorbídeos sobreviventes, 10 dias apos a primeira série. As infestações resultantes foram tôdas unissexuais (13 vezes por machos, 11 vezes por fêmeas, observando-se entre os sexos a relação de 1 : 1. Em 6 casos infestados por fêmeas, cerca de 15% destas apresentaram no útero ou no ootipo formações ovulares (figs. 1 a 15, desprovidas de estruturas embrionárias, cujo número variou entre 1 e 6. Êstes ovos, quando depositados no fígado, davam origem a ligeiro infiltrado de células epitelióides e não apresentavam organização embrionária. Não foram vistos ovos nos cortes de intestino. Os órgãos sexuais das fêmeas achavam-se aparentemente bem desenvolvidos em grande número de exemplares. Os machos apresentaram testículos de aparência normal, em número variável de 4 a 9. Em 1% dos exemplares examinados foram encontrados testículos supranumerários. Em 2 casos foram encontrados machos secundàriamente hermafroditas (respectivamente 29% e 25%.The dissection of 400 Australorbis olivaceiis from a brook situated in the grounds of the Instituto Oswaldo Cruz (Manguinhos showed that 8.25 per cent of them were naturally infested with Schistosoma mansoni. The cercariae of 24 snails were inoculated into 24 guinea pigs, each of the latter receiving the cercariae from a single snail. A second series of inoculations with the cercariae of 6 surviving snails was made 10 days after the first series. All resulting infestations were unisexual (13 with

  11. Ocorrência do molusco asiático Corbicula fluminea (Müller, 1774 (Bivalvia, Corbiculidae no baixo rio Negro, Amazônia central Occurrence of the Asian mollusc Corbicula fluminea (Müller, 1774 (Bivalvia, Corbiculidae in the lower Rio Negro, Central Amazon Region, Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Mansur Pimpão

    2008-01-01

    Full Text Available O rio Negro é um dos maiores afluentes do rio Amazonas, mas poucos moluscos foram registrados até o momento para aquele rio, representados apenas por gastrópodes. Foi registrada a presença do molusco bivalve exótico Corbicula fluminea na margem esquerda do baixo rio Negro, no lago do Tupé e no Catalão - margem direita do rio Negro, todas localidades no município de Manaus, Brasil. O registro foi realizado por meio da coleta de conchas e espécimes vivos. É o primeiro registro de C. fluminea para o estado do Amazonas e Amazônia central.The Rio Negro is one of the biggest Rio Amazonas tributaries. Few molluscs have been registered to that river yet, represented only by gastropods. It is reported the occurrence of the exotic bivalve mollusc Corbicula fluminea in left bank margin of Rio Negro, Lago do Tupé and Catalão - right bank margin of Rio Negro, all localities in the municipality of Manaus, Brazil. The species is recorded by a collection of shells and specimens alive. This is the first occurrence of C. fluminea in the Amazon State and Central Amazon.

  12. Determinaçao de metais classificados como de importância toxicológica no molusco bivalve Anadara notabilis (Röding, 1798: Encontrado em Galinhos, Rio grande do norte, Brasil Determination of metals of toxicological importance in the bivalve Anadara notabilis (Röding, 1798 of Galinhos, coast of Rio grande do norte, Brazil

    Directory of Open Access Journals (Sweden)

    Marcos A Urbano de Araújo

    2010-12-01

    Full Text Available Os moluscos bivalves são consumidos por todo o mundo, constituindo-se em um recurso natural de boa aceitação pela população. Foi escolhido o molusco Anadara notabilis (conhecido como Xibiu ou Búzio para este trabalho pelo seu tamanho característico, bem maior que os mariscos mais comuns, e também por não ter sido encontrado na literatura nenhuma informação toxicológica sobre esta classe de moluscos. Todos os íons metálicos foram determinados por espectroscopia de emissão ótica com plasma indutivamente acoplado (ICP-OES descrito pela metodologia U.S. EPA 6010C. Os resultados mostraram que estiveram presentes no molusco vários metais de caráter tóxico, porém apenas o cromo obteve valor acima do permitido pela legislação brasileira. Dentre os metais classificados como tóxicos o cobre que apresentou valor de 5,7 mg/Kg, o níquel que apresentou teor de 4,23 mg/Kg e o cromo, o único acima dos valores permitidos pela legislação brasileira, com teor de 1,7 mg/Kg, sempre considerando a amostra in natura. Como os moluscos têm a propriedade de acumular metais em seu organismo, para o consumo desse tipo de alimento, deve-se tomar cuidado com as áreas próximas de sua coleta ou se cultivado, é necessário prevenir fatores que influenciem em sua contaminação.Bivalve molluscs are consumed throughout the world, constituting a natural resource with good acceptance by the population. The mollusc Anadara notabilis (know as eared ark was chosen for this study due to its characteristic size, much larger than most common shellfish, and the lack of toxicological information found in literature for this class of mollusks when considering metal ions toxicity. Metal ions were measured by inductively coupled plasma optical emission spectroscopy (ICP-OES, method described by U.S. EPA 6010C. Results showed that several toxic metals were present in shellfish, however only chrome was measured in levels higher than those allowed by Brazilian

  13. DNA multigene characterization of Fasciola hepatica and Lymnaea neotropica and its fascioliasis transmission capacity in Uruguay, with historical correlation, human report review and infection risk analysis.

    Directory of Open Access Journals (Sweden)

    María Dolores Bargues

    2017-02-01

    Full Text Available Fascioliasis is a pathogenic disease transmitted by lymnaeid snails and recently emerging in humans, in part due to effects of climate changes, anthropogenic environment modifications, import/export and movements of livestock. South America is the continent presenting more human fascioliasis hyperendemic areas and the highest prevalences and intensities known. These scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks. A study including DNA marker sequencing of fasciolids and lymnaeids, an experimental study of the life cycle in Uruguay, and a review of human fascioliasis in Uruguay, are performed.The characterization of Fasciola hepatica from cattle and horses of Uruguay included the complete sequences of the ribosomal DNA ITS-2 and ITS-1 and mitochondrial DNA cox1 and nad1. ITS-2, ITS-1, partial cox1 and rDNA 16S gene of mtDNA were used for lymnaeids. Results indicated that vectors belong to Lymnaea neotropica instead of to Lymnaea viator, as always reported from Uruguay. The life cycle and transmission features of F. hepatica by L. neotropica of Uruguay were studied under standardized experimental conditions to enable a comparison with the transmission capacity of F. hepatica by Galba truncatula at very high altitude in Bolivia. On this baseline, we reviewed the 95 human fascioliasis cases reported in Uruguay and analyzed the risk of human infection in front of future climate change estimations.The correlation of fasciolid and lymnaeid haplotypes with historical data on the introduction and spread of livestock into Uruguay allowed to understand the molecular diversity detected. Although Uruguayan L. neotropica is a highly efficient vector, its transmission capacity is markedly lower than that of Bolivian G. truncatula. This allows to understand the transmission and epidemiological differences between Andean highlands

  14. DNA multigene characterization of Fasciola hepatica and Lymnaea neotropica and its fascioliasis transmission capacity in Uruguay, with historical correlation, human report review and infection risk analysis

    Science.gov (United States)

    Gayo, Valeria; Sanchis, Jaime; Artigas, Patricio; Khoubbane, Messaoud; Birriel, Soledad; Mas-Coma, Santiago

    2017-01-01

    Background Fascioliasis is a pathogenic disease transmitted by lymnaeid snails and recently emerging in humans, in part due to effects of climate changes, anthropogenic environment modifications, import/export and movements of livestock. South America is the continent presenting more human fascioliasis hyperendemic areas and the highest prevalences and intensities known. These scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks. A study including DNA marker sequencing of fasciolids and lymnaeids, an experimental study of the life cycle in Uruguay, and a review of human fascioliasis in Uruguay, are performed. Methodology/Principal findings The characterization of Fasciola hepatica from cattle and horses of Uruguay included the complete sequences of the ribosomal DNA ITS-2 and ITS-1 and mitochondrial DNA cox1 and nad1. ITS-2, ITS-1, partial cox1 and rDNA 16S gene of mtDNA were used for lymnaeids. Results indicated that vectors belong to Lymnaea neotropica instead of to Lymnaea viator, as always reported from Uruguay. The life cycle and transmission features of F. hepatica by L. neotropica of Uruguay were studied under standardized experimental conditions to enable a comparison with the transmission capacity of F. hepatica by Galba truncatula at very high altitude in Bolivia. On this baseline, we reviewed the 95 human fascioliasis cases reported in Uruguay and analyzed the risk of human infection in front of future climate change estimations. Conclusions/Significance The correlation of fasciolid and lymnaeid haplotypes with historical data on the introduction and spread of livestock into Uruguay allowed to understand the molecular diversity detected. Although Uruguayan L. neotropica is a highly efficient vector, its transmission capacity is markedly lower than that of Bolivian G. truncatula. This allows to understand the transmission and

  15. DNA sequence characterisation and phylogeography of Lymnaea cousini and related species, vectors of fascioliasis in northern Andean countries, with description of L. meridensis n. sp. (Gastropoda: Lymnaeidae

    Directory of Open Access Journals (Sweden)

    Bargues M Dolores

    2011-07-01

    Full Text Available Abstract Background Livestock fascioliasis is a problem throughout Ecuador, Colombia and Venezuela, mainly in Andean areas where the disease also appears to affect humans. Transmission patterns and epidemiological scenarios of liver fluke infection have shown to differ according to the lymnaeid vector snail species involved. These Andean countries present the vectors Lymnaea cousini, L. bogotensis and L. ubaquensis, unknown in the rest of Latin America. An exhaustive combined haplotype study of these species is performed by means of DNA sequencing of the nuclear ribosomal 18S RNA gene, ITS-2 and ITS-1, and mitochondrial DNA cox1 gene. Results The conserved 5.8S rDNA sequence corroborated that no pseudogenes are involved in the numerous non-microsatellite/minisatellite-related indels appearing between the ITS-2 and ITS-1 sequences when comparing different L. cousini - L. bogotensis populations. Sequence analyses and phylogenetic reconstruction methods including other lymnaeid vector species show that (i L. bogotensis is a synonym of L. cousini, (ii L. ubaquensis is a synonym of Pseudosuccinea columella, and (iii populations of L. cousini hitherto known from Venezuelan highlands indeed belong to a new species for which the name L. meridensis n. sp. is proposed. This new species is described and a complete phenotypic differentiation provided. Conclusions ITS-2, ITS-1 and cox1 prove to be good markers for specimen classification and haplotype characterisation of these morphologically similar lymnaeids in endemic areas. Analysis of the 18S gene and phylogenetic reconstructions indicate that L. cousini and L. meridensis n. sp. cluster in an evolutionary line different from the one of P. columella, despite their external resemblance. This suggests an evolutionary phenotypic convergence related to similar environments and which has given rise to frequent specimen misclassification. Body size and phylogenetic relationships of L. meridensis n. sp. with

  16. Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs Variação genética entre moluscos susceptíveis e não susceptíveis à infecção pelo Schistosoma através da análise do DNA polimórfico amplificado aleatóriamente (RAPDs

    Directory of Open Access Journals (Sweden)

    Abdel-Hamid Zaki ABDEL-HAMID

    1999-09-01

    Full Text Available Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers were used to amplify the extracted DNA by the polymerase chain reaction (PCR followed by polyacrylamide gel electrophoresis (PAGE and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.A susceptibilidade de moluscos à infecção por certos trematódeos e a sua capacidade como hospedeiro para o contínuo desenvolvimento é o problema mais deslumbrante nas relações parasita hospedeiro. O presente trabalho, focaliza nosso interesse na genética dos moluscos para determinar quais genes ou produtos gênicos são especificamente responsáveis pela susceptibilidade do molusco à infecção. DNA de alto peso molecular, foi extraído de ambos moluscos susceptíveis e não susceptíveis da espécie Biomphalaria tenagophila. Iniciadores aleatórios com 10 pares de bases foram usados na amplificação aleatória (RAPD de ambos os DNAs e análise por eletroforese em gel de poliacrilamida e coloração com prata. Os resultados mostram que a amplificação aleatória do DNA representa um eficiente caminho para a comparação dos genomas desde que marcadores moleculares foram detectados como variantes genéticos entre os moluscos susceptíveis e não susceptíveis.

  17. Atual distribuição geográfica dos moluscos hospedeiros intermediários do Schistosoma mansoni em Belo Horizonte, MG, Brasil Current geographic distribution of intermediate hosts mollusca of Schistosoma mansoni in Belo Horizonte, MG, Brazil

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    Cecília Pereira de Souza

    1981-12-01

    Full Text Available Procedeu-se ao levantamento malacológico do município de Belo Horizonte, MG, com o objetivo de avaliar a distribuição, densidade e taxa de infecção dos moluscos hospedeiros intermediários do Schistosoma mansoni. Foram coletadas 3.261 Biomphalaria glabrata em 1979-81, das quais 100 (3,1% estavam infectadas com S. mansoni. Registrou-se a existência de 36 criadouros (35,0% de B. glabrata em 102 locais pesquisados, sendo 23 na bacia hidrográfica de Pampulha e 13 na do ribeirão do Arrudas. Foram encontrados 2 criadouros de B. tenagophila e 2 de B. straminea. Registrou-se também a presenca de exemplares de Pomacea haustrum, Physa sp e Drepanotrema cimex. Compararam-se os dados obtidos atualmente com os publicados em 1967. Houve reducao de mais de 50% no número de criadouros de B.glabrata, principalmente em decorrencias da expansão e progresso da cidade. Na zona periférica a esquistossomose continua endêmica, havendo necessidade de novas obras de saneamento básico para se conseguir o controle da doença.Malacological surveys were conducted in Belo Horizonte with a view to obtain new data on the distribution and density of schistosomose bearing snails and their natural rate of infection by Schistosoma mansoni. Of 3.261 Biomphalaria glabrata collected during 1979-81, 100 (3,1% were found naturally infected. One hundred and two water collections were surveyed and 36 (35% were found harboring the mentioned snail species (23 of them in the watershed of Pampulha, 13 in the tributaires of the Arrudas creek. The species B. tenagophila was found in two waterbodies, and B. straminea in two other. Other snail species collected were Pomacea haustrum, Physa sp and Drepanotrema cimex. Data of this survey were compared with data published in 1967 and 50% reduction in the snail breeding places was observed. This reduction was due mainly to public works and engineering activities accompanying the growth of city. Schistosomiasis is still present in the

  18. Bioaccumulation and toxic effects of cadmium on feeding and growth of an Indian pond snail Lymnaea luteola L. under laboratory conditions.

    Science.gov (United States)

    Das, Sangita; Khangarot, B S

    2010-10-15

    Effects of dissolved cadmium exposure on the survival, feeding, growth rates and accumulation in Indian pond snails Lymnaea luteola L. were examined for a period of 7 weeks. The concentrations of cadmium tested were 0, 10, 32, 100, 320, 560, and 1000 microg l(-1). Cadmium exposure significantly inhibited the feeding and growth rates. At higher Cd concentrations snails refused to consume food offered as plant Marsilia sp. leaves. Cadmium mainly accumulated in soft tissues in a dose-dependent manner. After 4 and 7 weeks of exposure, the no observed effect concentration (NOEC) of Cd was 10 microg l(-1) and the lowest observed effect concentration (LOEC) was 32 microg l(-1). Reduction of growth (decrease in wet weight) was noticed followed by a high mortality in higher Cd concentrations. Significant reduction in food consumption and growth rates was found at 32 microg l(-1) and above Cd concentration. A significant relationship between Cd exposure and growth and feeding rates was noticed. The results obtained with these key aquatic organisms in the food chains complement those obtained with other aquatic organisms and gastropod snails. The findings of the present study and those of earlier studies suggested that Indian pond snail L. luteola are useful test organisms for ecotoxicology bioassays.

  19. Effects of self-fertilization, environmental stress and exposure to xenobiotics on fitness-related traits of the freshwater snail Lymnaea stagnalis.

    Science.gov (United States)

    Coutellec, Marie-Agnès; Lagadic, Laurent

    2006-03-01

    Genetic and ecological factors may interact in their effects on fitness. Such interactions are thus to be expected between inbreeding and exposure of a population to a toxicant. The magnitude of inbreeding depression is thought to increase in stressful environments. To test this hypothesis, we investigated the combined effects of environmental conditions and inbreeding on fitness in the self-fertile snail Lymnaea stagnalis, using a stress gradient (0-2) applied to a 100 isolated and paired lineages: laboratory control (0), outdoor microcosm control (1) and pesticide exposure under outdoor microcosm conditions (2). Outdoor stress conditions were maintained for 28 days prior to measurements of fitness traits (fecundity, hatching success, and size at hatching) under laboratory conditions, so that delayed environmental effects could be estimated. Under laboratory control conditions, we found significant initial family level heterogeneity for most measured traits, including physiological performances as assessed through energetic biomarkers. Whatever the environmental conditions, inbreeding depression was very low for progeny performances. Negative values of self-fertilization depression (SFD) were obtained. Unexpectedly, SFD showed a negative relationship with the assumed stress intensity, reflecting a higher sensitivity under pairing than under selfing, mostly due to parental fecundity. This suggests that stressful conditions may favour selfing. Stress intensity increased the distribution limits of both depression indices, suggesting that changes in fitness are less predictable in a population under stress. Implications of such findings for environmental risk assessment of pesticides are discussed.

  20. Larval trematodes (Digenea of the great pond snail, Lymnaea stagnalis (L., (Gastropoda, Pulmonata in Central Europe: a survey of species and key to their identification

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    Faltýnková A.

    2007-03-01

    Full Text Available A survey of cercariae and metacercariae (Trematoda, Digenea from the great pond snail (Lymnaea stagnalis in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3% L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected, Plagiorchis elegans (141 (both family Plagiorchiidae and Echinoparyphium aconiatum (153 (Echinostomatidae; 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71 (Omphalometridae, E. aconiatum (66, Echinostoma sp. (59 and Moliniella anceps (48 (Echinostomatidae. In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided.

  1. The role of spatial and temporal heterogeneity and competition in structuring trematode communities in the great pond snail, Lymnaea stagnalis (L.)

    Science.gov (United States)

    Soldánová, Miroslava; Kuris, Armand M.; Scholz, Tomáš; Lafferty, Kevin D.

    2012-01-01

    We assessed how spatial and temporal heterogeneity and competition structure larval trematode communities in the pulmonate snail Lymnaea stagnalis. To postulate a dominance hierarchy, mark-release-recapture was used to monitor replacements of trematode species within snails over time. In addition, we sampled the trematode community in snails in different ponds in 3 consecutive years. A total of 7,623 snails (10,382 capture events) was sampled in 7 fishponds in the Jindřichův Hradec and Třeboň areas in South Bohemia (Czech Republic) from August 2006 to October 2008. Overall, 39% of snails were infected by a community of 14 trematode species; 7% of snails were infected with more than 1 trematode species (constituting 16 double- and 4 triple-species combinations). Results of the null-model analyses suggested that spatial heterogeneity in recruitment among ponds isolated trematode species from each other, whereas seasonal pulses in recruitment increased species interactions in some ponds. Competitive exclusion among trematodes led to a rarity of multiple infections compared to null-model expectations. Competitive relationships among trematode species were hypothesized as a dominance hierarchy based on direct evidence of replacement and invasion and on indirect evidence. Seven top dominant species with putatively similar competitive abilities (6 rediae and 1 sporocyst species) reduced the prevalence of the other trematode species developing in sporocysts only.

  2. Considerations for test design to accommodate energy-budget models in ecotoxicology: a case study for acetone in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Barsi, Alpar; Jager, Tjalling; Collinet, Marc; Lagadic, Laurent; Ducrot, Virginie

    2014-07-01

    Toxicokinetic-toxicodynamic (TKTD) modeling offers many advantages in the analysis of ecotoxicity test data. Calibration of TKTD models, however, places different demands on test design compared with classical concentration-response approaches. In the present study, useful complementary information is provided regarding test design for TKTD modeling. A case study is presented for the pond snail Lymnaea stagnalis exposed to the narcotic compound acetone, in which the data on all endpoints were analyzed together using a relatively simple TKTD model called DEBkiss. Furthermore, the influence of the data used for calibration on accuracy and precision of model parameters is discussed. The DEBkiss model described toxic effects on survival, growth, and reproduction over time well, within a single integrated analysis. Regarding the parameter estimates (e.g., no-effect concentration), precision rather than accuracy was affected depending on which data set was used for model calibration. In addition, the present study shows that the intrinsic sensitivity of snails to acetone stays the same across different life stages, including the embryonic stage. In fact, the data on egg development allowed for selection of a unique metabolic mode of action for the toxicant. Practical and theoretical considerations for test design to accommodate TKTD modeling are discussed in the hope that this information will aid other researchers to make the best possible use of their test animals. © 2014 SETAC.

  3. Chlorophyllin Bait Formulation and Exposure to Different Spectrum of Visible Light on the Reproduction of Infected/Uninfected Snail Lymnaea acuminata

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    Navneet Kumar

    2016-01-01

    Full Text Available Fasciolosis is a waterborne disease, caused by Fasciola species. Snail Lymnaea acuminata is an intermediate host of these flukes. Control of snail population is major tool in reducing the incidences. Variation in light intensity and wavelength caused significant changes in reproduction pattern of snails. Maximum fecundity was noted with bait containing carbohydrate (starch, 468 ± 0.10/20 snails or amino acid (serine, 319 ± 0.29/20 snails as attractant. Sublethal feeding of chlorophyllin bait with starch or serine attractant to infected and uninfected snails caused significant reduction in fecundity, hatchability, and survivability. These significant changes are observed in snails exposed to different spectral band of visible light and sunlight. Maximum fecundity of 536 ± 2.0 and minimum of 89.3 ± 0.4 were noted in snails not fed with bait and exposed to sunlight and red spectral band, respectively. There was complete arrest in the fecundity of infected and uninfected snails and no survivability of uninfected snails after 48 h feeding with bait containing chlorophyllin + attractant. Minimum hatchability (9.25 ± 0.5 was noted in red light exposed, chlorophyllin + starch fed infected snails and hatching period of bait fed snails was prolonged. Conclusively, chlorophyllin bait and red light reduce reproduction capacity in snails.

  4. Chlorophyllin Bait Formulation and Exposure to Different Spectrum of Visible Light on the Reproduction of Infected/Uninfected Snail Lymnaea acuminata.

    Science.gov (United States)

    Kumar, Navneet; Singh, D K; Singh, Vinay Kumar

    2016-01-01

    Fasciolosis is a waterborne disease, caused by Fasciola species. Snail Lymnaea acuminata is an intermediate host of these flukes. Control of snail population is major tool in reducing the incidences. Variation in light intensity and wavelength caused significant changes in reproduction pattern of snails. Maximum fecundity was noted with bait containing carbohydrate (starch, 468 ± 0.10/20 snails) or amino acid (serine, 319 ± 0.29/20 snails) as attractant. Sublethal feeding of chlorophyllin bait with starch or serine attractant to infected and uninfected snails caused significant reduction in fecundity, hatchability, and survivability. These significant changes are observed in snails exposed to different spectral band of visible light and sunlight. Maximum fecundity of 536 ± 2.0 and minimum of 89.3 ± 0.4 were noted in snails not fed with bait and exposed to sunlight and red spectral band, respectively. There was complete arrest in the fecundity of infected and uninfected snails and no survivability of uninfected snails after 48 h feeding with bait containing chlorophyllin + attractant. Minimum hatchability (9.25 ± 0.5) was noted in red light exposed, chlorophyllin + starch fed infected snails and hatching period of bait fed snails was prolonged. Conclusively, chlorophyllin bait and red light reduce reproduction capacity in snails.

  5. Bioaccumulation and toxic effects of cadmium on feeding and growth of an Indian pond snail Lymnaea luteola L. under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Das, Sangita [Ecotoxicology Laboratory, Indian Institute of Toxicology Research, (Formerly: Industrial Toxicology Research Centre), Council of Scientific and Industrial Research (CSIR), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226 001 (India); Khangarot, B.S., E-mail: bkhangarot@hotmail.com [Ecotoxicology Laboratory, Indian Institute of Toxicology Research, (Formerly: Industrial Toxicology Research Centre), Council of Scientific and Industrial Research (CSIR), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226 001 (India)

    2010-10-15

    Effects of dissolved cadmium exposure on the survival, feeding, growth rates and accumulation in Indian pond snails Lymnaea luteola L. were examined for a period of 7 weeks. The concentrations of cadmium tested were 0, 10, 32, 100, 320, 560, and 1000 {mu}g l{sup -1}. Cadmium exposure significantly inhibited the feeding and growth rates. At higher Cd concentrations snails refused to consume food offered as plant Marsilia sp. leaves. Cadmium mainly accumulated in soft tissues in a dose-dependent manner. After 4 and 7 weeks of exposure, the no observed effect concentration (NOEC) of Cd was 10 {mu}g l{sup -1} and the lowest observed effect concentration (LOEC) was 32 {mu}g l{sup -1}. Reduction of growth (decrease in wet weight) was noticed followed by a high mortality in higher Cd concentrations. Significant reduction in food consumption and growth rates was found at 32 {mu}g l{sup -1} and above Cd concentration. A significant relationship between Cd exposure and growth and feeding rates was noticed. The results obtained with these key aquatic organisms in the food chains complement those obtained with other aquatic organisms and gastropod snails. The findings of the present study and those of earlier studies suggested that Indian pond snail L. luteola are useful test organisms for ecotoxicology bioassays.

  6. The population density of Lymnaea columella (Say, 1817) (Mollusca, Lymnaeidae) an intermediate host of Fasciola hepatica (Linnaeus, 1758), in the Caparaó microregion, ES, Brazil.

    Science.gov (United States)

    D'Almeida, S C G; Freitas, D F; Carneiro, M B; Camargo, P F; Azevedo, J C; Martins, I V F

    2016-06-01

    The aim of this study was to monitor the population density of Lymnaea columella, an intermediate host of Fasciola hepatica, in various aquatic habitats and in drinking water in the area of the Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, on Caparaó Microregion, municipality of Alegre, state of Espírito Santo, Brazil. Monthly samplings were performed at certain points between drainage areas and drinking water in cattle and goat production systems during the years 2010 to 2013. The mean temperature, precipitation and the frequency of samples of L. columella were analysed graphically according the monthly average during the study period. A total of 2,038 molluscs were collected, 1558 of which were L. columella, that predominated in all sampled points. The highest average of specimens observed for L. columella was in the years 2010 and 2013 (51.0), and occurred decreased in 2011 (19.8). The temperature and precipitation averaged is 23.7 °C and 141 mm/year, respectively. Rainfall peak occurred in March (2011, 2013) and November (2012), during these periods the population of L. columella growth. There was no significant difference in the relationship between the specimens observed with seasons (dry-wet), thus the population of L. columella remained stable and can be found throughout the year.

  7. Isolation and detection of Fasciola hepatica DNA in Lymnaea viatrix from formalin-fixed and paraffin-embedded tissues through multiplex-PCR.

    Science.gov (United States)

    Magalhães, Kelly Grace; Jannotti-Passos, Liana K; Caldeira, Roberta L; Berne, Maria Elisabeth Aires; Muller, Gertrude; Carvalho, Omar S; Lenzi, Henrique Leonel

    2008-04-15

    Detection of Fasciola hepatica infection in Lymnaea viatrix through analysis of histological cuts is based upon morphological characters of the parasite during the intra-mollusk phase of parasitism. At this stage, trematode forms are very similar and, thus, very difficult to differentiate. Specific detection may also be impaired by the presence of other helminthes in the mollusk. Histological samples are usually fixed in formalin, embedded in paraffin, sectioned and HE stained. In the current study, a method for the extraction of DNA from formalin-fixed, paraffin-embedded tissues was standardized by means of deparaffinizing with xylol and digesting with proteinase K. Extracted DNA was amplified in a multiplex-PCR, by using simultaneous primers in a single reaction under high stringency conditions. Results showed specific amplification of DNA from the trematode and the snails. The technique was sensitive enough to detect F. hepatica infections in L. viatrix, in histological sections in which the presence of larval stages could not be observed through brightfield microscopy. The profiles generated were: stair bands referring to F. hepatica DNAmt amplification; a band of 1200 bp referring to L. viatrix ITS and another of 1300 bp referring to F. hepatica ITS and other trematodes. Multiplex-PCR has shown to be a fast, safe, highly sensitive and specific method, which is able to amplify DNA from fixed tissues, despite a low DNA quantity and its degradation caused by fixation processes. Such methodology may be useful in studies on fascioliasis epidemiology, enabling the use of material from histological collections.

  8. The population density of Lymnaea columella (Say, 1817 (Mollusca, Lymnaeidae an intermediate host of Fasciola hepatica (Linnaeus, 1758, in the Caparaó microregion, ES, Brazil

    Directory of Open Access Journals (Sweden)

    S. C. G. D’Almeida

    Full Text Available Abstract The aim of this study was to monitor the population density of Lymnaea columella, an intermediate host of Fasciola hepatica, in various aquatic habitats and in drinking water in the area of the Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, on Caparaó Microregion, municipality of Alegre, state of Espírito Santo, Brazil. Monthly samplings were performed at certain points between drainage areas and drinking water in cattle and goat production systems during the years 2010 to 2013. The mean temperature, precipitation and the frequency of samples of L. columella were analysed graphically according the monthly average during the study period. A total of 2,038 molluscs were collected, 1558 of which were L. columella, that predominated in all sampled points. The highest average of specimens observed for L. columella was in the years 2010 and 2013 (51.0, and occurred decreased in 2011 (19.8. The temperature and precipitation averaged is 23.7 °C and 141 mm/year, respectively. Rainfall peak occurred in March (2011, 2013 and November (2012, during these periods the population of L. columella growth. There was no significant difference in the relationship between the specimens observed with seasons (dry-wet, thus the population of L. columella remained stable and can be found throughout the year.

  9. Extremely low frequency magnetic field and the hatching rate of Fasciola hepatica eggs, the fecundity and survival of liver fluke-infected snail, Lymnaea truncatula.

    Science.gov (United States)

    Kołodziejczyk, Lidia; Kuźna-Grygiel, Wanda; Gonet, Bolesław; Podraza, Wojciech

    2010-01-01

    Eggs of Fasciola hepatica were exposed for 10 days to extremely low frequency magnetic field (ELFMF) at the frequency of 50 Hz and density of 2 mT (rms). The results show an accelerated hatching of F. hepatica eggs in relation to control (non-exposed) group. The host snails, Lymnaea truncatula, were divided into three groups; those of groups I and II were infected with the miracidia of F. hepatica hatched from control egg culture, whereas those of group III were infected with miracidia hatched from eggs affected by ELFMF. Thereafter, snails of groups II and III were exposed to ELFMF for 53 days, whereas those of group I were not exposed. At day 14 post infection, a significant decrease was observed in the number of cocoons laid by snails of group III, compared with control. Also, significant mortality in group III snails was observed 42 days post infection. The increased mortality and a lower number of cocoons laid by group III snails have probably resulted from enhanced stimulation of metacercarial parthenogenetic reproduction in consequence of infecting the molluscs with miracidia reared under ELFMF.

  10. PCR-RFLP Analysis of 28 SrDNA for Specification of Fasciola gigantica (Cobbold, 1855) in the Infected Lymnaea auricularia (Linnaeus, 1785) Snails from Northwestern Iran.

    Science.gov (United States)

    Yakhchali, Mohammad; Malekzadeh-Viayeh, Reza; Imani-Baran, Abass

    2014-09-01

    Fasciolosis in livestock is a crucial concern in the globe, mainly due to its impact on human health. The aim of this study was to determine the rate of infection with Fasciola gigantica (Cobbold, 1855) larvae in the field-collected snails of Lymnaea auricularia (Linnaeus, 1785) from northwestern Iran using a molecular approach. A total of 6,759 pond snails were collected from 28 freshwater bodies in West Azarbaijan. PCR was performed to amplify a 618-bp fragment of the nuclear 28 SrRNA gene of Fasciola. The PCR products were digested by AvaII restriction enzyme to create restriction fragment length polymorphism (RFLP) patterns specific for the detection of F. gigantica. Of the total collected snails 496 (7.34 %) were L. auricularia, among which 4.64% (23 out of 496) were infected with a Fasciola species according to the PCR analysis. Only 2.22% (11 out of 496) of the infected snails were from the mountainous areas. The highest Fasciola infection rate recorded in the snails of a single site was 1.81% (9 out of 496 snails). Based on the RFLP pattern, F. gigantica accounted for 2.42% of the infection rates in the study sites. Application of PCR-RFLP was proven to be a useful approach for valid and robust detection of the infection with F. gigantica in its intermediate host snails. These findings may therefore be applicable for establishment of the control programs against dissemination of the infection in different regions.

  11. Prevalence of Fasciola hepatica in the intermediate host Lymnaea truncatula detected by real time TaqMan PCR in populations from 70 Swiss farms with cattle husbandry.

    Science.gov (United States)

    Schweizer, G; Meli, M L; Torgerson, P R; Lutz, H; Deplazes, P; Braun, U

    2007-11-30

    Bovine fasciolosis is an economically important parasitic disease. Quantitative real time PCR was utilized to determine the prevalence of Fasciola hepatica in the snail intermediate host Lymnaea truncatula from 70 selected, infected Swiss cattle farms, and to gain information on the infection risk to the definitive host. Snails from 130 habitats (36 streams, 21 wells, 24 drainage ditches, 33 spring swamps, 14 reeds, 1 drainage shaft and 1 pond) originating from 71 dairy cow pastures, 39 pastures for young stock, 14 hay fields and 6 dry cow pastures were collected. Of these, 51 populations were found to be infected with F. hepatica. A total of 4733 snails were examined of which 331 were infected (7.0%). The numbers of snails collected from different sites ranged from 1 to 159 snails. Clustering of infection in snails was found on the farm of origin with a mixed logistic model with random effects. The risk of infection of L. truncatula with F. hepatica was significantly higher in populations originating from spring swamps, wells and reeds compared to populations from streams. In addition the risk of snail infection was significantly lower in populations collected in young stock and dry cow pastures compared to dairy cow pastures. The greater the population size collected from a habitat also increased the risk of an individual snail being infected.

  12. Chlorophyllin Bait Formulation and Exposure to Different Spectrum of Visible Light on the Reproduction of Infected/Uninfected Snail Lymnaea acuminata

    Science.gov (United States)

    Kumar, Navneet; Singh, D. K.; Singh, Vinay Kumar

    2016-01-01

    Fasciolosis is a waterborne disease, caused by Fasciola species. Snail Lymnaea acuminata is an intermediate host of these flukes. Control of snail population is major tool in reducing the incidences. Variation in light intensity and wavelength caused significant changes in reproduction pattern of snails. Maximum fecundity was noted with bait containing carbohydrate (starch, 468 ± 0.10/20 snails) or amino acid (serine, 319 ± 0.29/20 snails) as attractant. Sublethal feeding of chlorophyllin bait with starch or serine attractant to infected and uninfected snails caused significant reduction in fecundity, hatchability, and survivability. These significant changes are observed in snails exposed to different spectral band of visible light and sunlight. Maximum fecundity of 536 ± 2.0 and minimum of 89.3 ± 0.4 were noted in snails not fed with bait and exposed to sunlight and red spectral band, respectively. There was complete arrest in the fecundity of infected and uninfected snails and no survivability of uninfected snails after 48 h feeding with bait containing chlorophyllin + attractant. Minimum hatchability (9.25 ± 0.5) was noted in red light exposed, chlorophyllin + starch fed infected snails and hatching period of bait fed snails was prolonged. Conclusively, chlorophyllin bait and red light reduce reproduction capacity in snails. PMID:26925296

  13. Comparative horizontal starch gel isoenzyme electrophoresis of Lymnaea (Bullastra) cumingiana (Pulmonata: Lymnaeidae) and related taxa in the Indo-Pacific region.

    Science.gov (United States)

    Monzon, R B; Thammapalerd, N; Kitikoon, V; Temcharoen, P; Sornmani, S; Viyanant, V

    1994-03-01

    Foot muscle tissue extracts from six lymnaeid species of the Indo-Pacific region [Lymnaea (Bullastra) cumingiana and L. (Radix) quadrasi from the Philippines, L. (R.) rubiginosa from Indonesia and Thailand, and L. (R.) viridis from Guam and Hong Kong] were subjected to horizontal starch gel isoenzyme electrophoresis and assayed for seven isoenzymes (AcP, AlP, CA, EST, LAP, CAT and GOT) to elucidate their taxonomic relationships. L. cumingiana exhibited banding patterns for EST, LAP and CAT uniquely different from the rest, thus supporting the hypothesis that it is a distinct species. Zymogram patterns for AlP, CA, EST and LAP attest to the close affinity between L. quadrasi and L. rubiginosa (Indonesia and Thailand). Minor differences suggest a closer relationship between the two geographical strains of L. rubiginosa than with L. quadrasi, lending support to the hypothesis that L. quadrasi is inseparable as a race or variety from the typical L. swinhoei Adams, which in turn is but a race of L. auricularia, which also encompasses L. rubiginosa. The two geographical strains of L. viridis from Guam and Hong Kong showed the greatest consistency with regards to similarity and congruence in banding patterns. Non-specific esterases (EST) were the most useful in distinguishing the six species from each other.

  14. A comparison of metal levels and antioxidant enzymes in freshwater snails, Lymnaea natalensis, exposed to sediment and water collected from Wright Dam and Lower Mguza Dam, Bulawayo, Zimbabwe.

    Science.gov (United States)

    Siwela, A H; Nyathi, C B; Naik, Y S

    2010-10-01

    We compared the bioaccumulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to elements of two differently polluted dams. 45 snails were exposed to sediment and water collected from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water collected from Lower Mguza Dam (polluted dam). Except for Fe in sediment and Pb in water, metal concentrations were statistically higher in sediment and water collected from Lower Mguza Dam. Lead, Cd and Zn were two times higher in tissues of snails exposed to Lower Mguza Dam elements. On one hand, superoxide dismutase (SOD), diphosphotriphosphodiaphorase (DTD) and catalase (CAT) activities were significantly lower whilst malondialdehyde (MDA) levels were significantly higher in tissues of snails exposed to Lower Mguza Dam sediment and water. On the other hand, selenium-dependent glutathione peroxidase (Se-GPX) activity was significantly elevated in tissues of snails exposed to Lower Mguza Dam sediment and water. Snails exposed to Lower Mguza Dam elements seem to have responded to pollution by increasing CAT and Se-GPX specific activity in an effort to detoxify peroxides produced as a result of metal induced oxidative stress.

  15. Accumulation of free and covalently bound microcystins in tissues of Lymnaea stagnalis (Gastropoda) following toxic cyanobacteria or dissolved microcystin-LR exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie, E-mail: emilie.lance@live.f [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France); Neffling, Milla-Riina [Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistoekatu 6, FI-20520 Turku (Finland); Gerard, Claudia [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France); Meriluoto, Jussi [Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistoekatu 6, FI-20520 Turku (Finland); Bormans, Myriam [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France)

    2010-03-15

    Accumulation of free microcystins (MCs) in freshwater gastropods has been demonstrated but accumulation of MCs covalently bound to tissues has never been considered so far. Here, we follow the accumulation of total (free and bound) MCs in Lymnaea stagnalis exposed to i) dissolved MC-LR (33 and 100 mug L{sup -1}) and ii) Planktothrix agardhii suspensions producing 5 and 33 mug MC-LR equivalents L{sup -1} over a 5-week period, and after a 3-week depuration period. Snails exposed to dissolved MC-LR accumulated up to 0.26 mug total MCs g{sup -1} dry weight (DW), with no detection of bound MCs. Snails exposed to MCs producing P. agardhii accumulated up to 69.9 mug total MCs g{sup -1} DW, of which from 17.7 to 66.7% were bound. After depuration, up to 15.3 mug g{sup -1} DW of bound MCs were detected in snails previously exposed to toxic cyanobacteria, representing a potential source of MCs transfer through the food web. - The study concerns accumulation and elimination of both free and bound microcystins (MCs) in tissues of a gastropod exposed to MCs producing cyanobacteria or dissolved MC-LR.

  16. Bait formulations of molluscicides and their effects on biochemical changes in the ovotestis of snail Lymnaea acuminata (Mollusca; Gastropoda:Lymnaeidae

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    Pradeep Kumar

    2011-10-01

    Full Text Available The effect of sub-lethal feeding of bait formulations containing molluscicidal component of Ferula asafoetida (ferulic acid, umbelliferone, Syzygium aromaticum (eugenol and Carum carvi (limonene on biochemical changes in the ovotestis of snail Lymnaea acuminata were studied. Bait formulations feeding to L. acuminata were studied in clear glass aquaria having diameter of 30 cm. Baits were prepared from different binary combinations of attractant amino acid (valine, aspartic acid, lysine and alanine 10 mM in 100 mL of 2% agar solution + sub-lethal (20% and 60% of 24h LC50 doses of different molluscicides (ferulic acid, umbelliferone, eugenol and limonene. These baits caused maximum significant reduction in free amino acid, protein, DNA, RNA levels i.e. 41.37, 23.56, 48.36 and 14.29% of control in the ovotestis of the snail, respectively. Discontinuation of feeding after treatment of 60% of 96h LC50 of molluscicide containing bait for next 72h caused a significant recovery in free amino acid, protein, DNA and RNA levels in the ovotestis of L. acuminata.

  17. Crystal structure of Lymnaea stagnalis AChBP complexed with the potent nAChR antagonist DHβE suggests a unique mode of antagonism.

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    Azadeh Shahsavar

    Full Text Available Nicotinic acetylcholine receptors (nAChRs are pentameric ligand-gated ion channels that belong to the Cys-loop receptor superfamily. These receptors are allosteric proteins that exist in different conformational states, including resting (closed, activated (open, and desensitized (closed states. The acetylcholine binding protein (AChBP is a structural homologue of the extracellular ligand-binding domain of nAChRs. In previous studies, the degree of the C-loop radial extension of AChBP has been assigned to different conformational states of nAChRs. It has been suggested that a closed C-loop is preferred for the active conformation of nAChRs in complex with agonists whereas an open C-loop reflects an antagonist-bound (closed state. In this work, we have determined the crystal structure of AChBP from the water snail Lymnaea stagnalis (Ls in complex with dihydro-β-erythroidine (DHβE, which is a potent competitive antagonist of nAChRs. The structure reveals that binding of DHβE to AChBP imposes closure of the C-loop as agonists, but also a shift perpendicular to previously observed C-loop movements. These observations suggest that DHβE may antagonize the receptor via a different mechanism compared to prototypical antagonists and toxins.

  18. CHARACTERIZATION OF MOLLUSCICIDAL COMPONENT OF Moringa oleifera LEAF AND Momordica charantia FRUITS AND THEIR MODES OF ACTION IN SNAIL Lymnaea acuminata

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    Aparna Upadhyay

    2013-07-01

    Full Text Available SUMMARY The molluscicidal activity of the leaf powder of Moringa oleifera and lyophilized fruit powder of Momordica charantia against the snail Lymnaea acuminata was time and concentration dependent. M. oleifera leaf powder (96 h LC50: 197.59 ppm was more toxic than M. charantia lyophilized fruit powder (96 h LC50: 318.29 ppm. The ethanolic extracts of M. oleifera leaf powder and Momordica charantia lyophilized fruit powder were more toxic than other organic solvent extracts. The 96 h LC50 of the column purified fraction of M. oleifera leaf powder was 22.52 ppm, while that of M. charantia lyophilized fruit powder was 6.21 ppm. Column, thin layer and high performance liquid chromatography analysis show that the active molluscicidal components in M. oleifera leaf powder and lyophilized fruit of M. charantia are benzylamine (96 h LC50: 2.3 ppm and momordicine (96 h LC50: 1.2 ppm, respectively. Benzylamine and momordicine significantly inhibited, in vivo and in vitro, the acetylcholinesterase (AChE, acid and alkaline phosphatase (ACP/ALP activities in the nervous tissues of L. acuminata. Inhibition of AChE, ACP and ALP activity in the nervous tissues of L. acuminata by benzylamine and momordicine may be responsible for the molluscicidal activity of M. oleifera and M. charantia fruits, respectively.

  19. Effects of in vitro and in vivo lead exposure on voltage-dependent calcium channels in central neurons of Lymnaea stagnalis.

    Science.gov (United States)

    Audesirk, G

    1987-01-01

    Currents through calcium channels of members of an identified cluster of neurons (B cells) in the pond snail Lymnaea stagnalis were studied under voltage clamp. The normal physiological saline was modified to maximize the visibility of voltage-dependent calcium currents and minimize contamination by other currents. Barium was used as the charge carrier for the calcium channels. Depolarizing voltage steps induce an inward current, the magnitude of which varies with the barium concentration. In brains taken from animals not exposed in vivo to lead, in vitro addition of lead acetate to the recording medium (0.25 to 14 microM) inhibits the barium current by 59 +/- 14% (mean +/- s.d.), in a manner that is independent of the lead concentration. The magnitude of the residual current still varies with the barium concentration. The voltage dependence of the current appears to be unaffected by lead. In contrast to some other calcium-channel blockers, such as cobalt, the inhibition of barium currents by in vitro lead exposure is irreversible, at least in short-term experiments. Contrary to expectations based on these in vitro results, barium currents in B cells of animals exposed to 5 microM lead for 6 to 12 weeks in vivo were approximately twice as large as barium currents in B cells from unexposed controls, when both were recorded in lead-free saline. It is possible that chronic in vivo lead exposure causes an increase in the number of calcium channels in these neurons.

  20. Comunidad de moluscos asociados al mejillón verde Perna viridis (Mollusca: Bivalvia y sus relaciones tróficas en la costa norte de la Península de Araya, Estado Sucre, Venezuela

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    Sioliz Villafranca

    2006-12-01

    Full Text Available Perna viridis es un bivalvo procedente del Indo-Pacífico que habita en la zona intermareal y ha invadido varios ecosistemas de la costa norte del estado Sucre, Venezuela. Con la finalidad de realizar un estudio sobre las comunidades de moluscos asociadas a esta especie y sus relaciones tróficas, se llevaron a cabo muestreos bimensuales entre octubre/97 y agosto/98, en un banco natural de mejillones a dos metros de profundidad en la costa norte de la península de Araya (10°40’N -48°63’W. Los organismos fueron recolectados delimitando el área con una cuadrícula de 0.25 m². Se identificaron los organismos hasta la categoría de especies utilizando claves específicas para moluscos y bibliográficamente se les determinó categoría trófica.Se capturó un total de 1 235 individuos de P. viridis y asociados a la especie 3 163 especímenes pertenecientes al phylum Mollusca, contenidos en tres clases: Bivalvia,Gastropoda y Polyplacophora. Éstas estuvieron representadas por 50 especies correspondientes a 10 órdenes, 24 familias; para los gasterópodos se contabilizaron 25 especies, para los bivalvos 22 y tres para los poliplacóforos. Del total de las especies, 40% fueron filtradoras, 26% carnívoras, 24% herbívoras y el 10% restante presentó dos categorías.De las filtradoras las más representativas fueron: Perna perna, Musculus lateralis, Crassostrea rhizophorae y Ostrea equestris; en el grupo de los carnívoros dominaron tres especies de la familia Columbellidae:Mitrella lunata, Anachis obesa y Nitidella ocellata y para el grupo de los herbívoros destacaron dos especies de la familia Fisurellidae: Diodora cayenensis y D. minuta. Se registraron dos especies filtradoras-detritívoras, y tres especies herbívoras-filtradoras representantes del género C repidula. El alto porcentaje de filtradores sería un indicativo de que dentro de este sistema probablemente hay una mayor disponibilidad de fracciones alimenticias para este grupo

  1. Efeito da disponibilidade de nitrogênio no consumo de oxigênio durante a mineralização de Scirpus cubensis da Lagoa do Infernão (São Paulo, Brasil - DOI: 10.4025/actascibiolsci.v29i2.524 Effect of nitrogen availability on the oxygen consumption during mineralization of Scirpus cubensis from Infernão Lagoon (São Paulo-Brazil - DOI: 10.4025/actascibiolsci.v29i2.524

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    Marcela Bianchessi da Cunha Santino

    2007-12-01

    Full Text Available Neste estudo, avaliou-se a influência de adições de nitrogênio no consumo de oxigênio durante a decomposição de Scirpus cubensis, por meio de ensaios de laboratório. Foram determinados: as concentrações de oxigênio dissolvido, o pH, a condutividade elétrica e a temperatura da água. Os resultados mostraram acidificação inicial que diminuíram gradualmente, indicando grande liberação de matéria orgânica reduzida e formação subseqüente de CO2. As câmaras de decomposição com maiores concentrações de nitrato apresentaram valores de pH mais alto. A condutividade elétrica mostrou pequeno incremento com o passar do tempo e aumento abrupto com a intensificação das concentrações de nitrato. O consumo de oxigênio máximo global aumentou até a concentração de nitrato de 6,37 mg L-1, depois decresceu. Os coeficientes globais de consumo de oxigênio apresentaram uma tendência oposta às quantidades máximas de oxigênio consumido. Os coeficientes de consumo de oxigênio, relacionados com a mineralização das frações particuladas, tenderam a aumentar com a elevação da concentração de nitrato. O aumento do nível de nitrato afetou diferentemente a decomposição das frações da matéria orgânica; a matéria orgânica particulada foi mais facilmente degradada do que a dissolvida em presença de maiores concentrações de nitrato.This study evaluated the influence of nitrogen additions in the oxygen uptake during decomposition of Scirpus cubensis, through laboratory assays. The dissolved oxygen, pH, electrical conductivity (EC and water temperature were measured. The results showed an initial acidification that decreased gradually, indicating great release of reduced organic matter and subsequent CO2 formation. The decomposition chambers with greater nitrate concentrations exhibited higher pH mean values. The temporal variation of EC showed a small increase and an abrupt increase with increasing nitrate concentrations

  2. Seasonal variation in abiotic factors and ferulic acid toxicity in snail-attractant pellets against the intermediate host snail Lymnaea acuminata.

    Science.gov (United States)

    Agrahari, P; Singh, D K

    2013-11-01

    Laboratory evaluation was made to access the seasonal variations in abiotic environmental factors temperature, pH, dissolved oxygen, carbon dioxide, electrical conductivity and ferulic acid toxicity in snail-attractant pellets (SAP) against the intermediate host snail Lymnaea acuminata in each month of the years 2010 and 2011. On the basis of a 24-h toxicity assay, it was noted that lethal concentration values of 4.03, 3.73% and 4.45% in SAP containing starch and 4.16, 4.23% and 4.29% in SAP containing proline during the months of May, June and September, respectively, were most effective in killing the snails, while SAP containing starch/proline + ferulic acid was least effective in the month of January/February (24-h lethal concentration value was 7.67%/7.63% in SAP). There was a significant positive correlation between lethal concentration value of ferulic acid containing SAP and levels of dissolved O2 /pH of water in corresponding months. On the contrary, a negative correlation was observed between lethal concentration value and dissolved CO2 /temperature of test water in the same months. To ascertain that such a relationship between toxicity and abiotic factors is not co-incidental, the nervous tissue of treated (40% and 80% of 24-h lethal concentration value) and control group of snails was assayed for the activity of acetylcholinesterase (AChE) in each of the 12 months of the same year. There was a maximum inhibition of 58.43% of AChE, in snails exposed to 80% of the 24-h lethal concentration value of ferulic acid + starch in the month of May. This work shows conclusively that the best time to control snail population with SAP containing ferulic acid is during the months of May, June and September.

  3. Growth inhibition in early life-stage tests predicts full life-cycle toxicity effects of lead in the freshwater pulmonate snail, Lymnaea stagnalis.

    Science.gov (United States)

    Munley, Kathleen M; Brix, Kevin V; Panlilio, Jennifer; Deforest, David K; Grosell, Martin

    2013-03-15

    The freshwater pulmonate snail, Lymnaea stagnalis, is the most sensitive freshwater organism tested to date for several metals (Co, Cu, Pb, Ni) based on 28 d early life-stage (ELS) tests in which growth was the most sensitive endpoint. The United States Environmental Protection Agency (USEPA) has expressed concern that growth in 28 d ELS tests with mollusks may overpredict toxicity because of the potential for recovery in a full life-cycle (LC) test. Consequently, the USEPA only accepts the survival endpoint for these tests in establishing water quality criteria (WQC). To address this concern, the current study aimed to test the sensitivity of L. stagnalis to Pb in a 56 d full LC test evaluating survival, growth, reproductive and embryonic growth endpoints and compare the estimated effect levels to those established using the 28 d ELS test design. The most sensitive endpoints in this study were 28 d growth and 56 d egg mass production, both with a NOEC of Snails exposed to 1.0 and 2.7 μg L(-1) Pb showed full and partial recovery from growth inhibition between 28 and 56 d. While this recovery supports the USEPA's concern about the 28 d growth endpoint; considering the reproductive lifespan of L. stagnalis and the recovery dose-response, we conclude that the 28 d growth endpoint will be within a factor of 3 of full LC endpoints. This is consistent with the level of precision previously determined for fish ELS tests, which the USEPA accepts for WQC derivation, and suggests that tests using 28 d ELS growth endpoint for L. stagnalis may be acceptable for inclusion in WQC derivation.

  4. Development of partial life-cycle experiments to assess the effects of endocrine disruptors on the freshwater gastropod Lymnaea stagnalis: a case-study with vinclozolin.

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    Ducrot, Virginie; Teixeira-Alves, Mickaël; Lopes, Christelle; Delignette-Muller, Marie-Laure; Charles, Sandrine; Lagadic, Laurent

    2010-10-01

    Long-term effects of endocrine disruptors (EDs) on aquatic invertebrates remain difficult to assess, mainly due to the lack of appropriate sensitive toxicity test methods and relevant data analysis procedures. This study aimed at identifying windows of sensitivity to EDs along the life-cycle of the freshwater snail Lymnaea stagnalis, a candidate species for the development of forthcoming test guidelines. Juveniles, sub-adults, young adults and adults were exposed for 21 days to the fungicide vinclozolin (VZ). Survival, growth, onset of reproduction, fertility and fecundity were monitored weekly. Data were analyzed using standard statistical analysis procedures and mixed-effect models. No deleterious effect on survival and growth occurred in snails exposed to VZ at environmentally relevant concentrations. A significant impairment of the male function occurred in young adults, leading to infertility at concentrations exceeding 0.025 μg/L. Furthermore, fecundity was impaired in adults exposed to concentrations exceeding 25 μg/L. Biological responses depended on VZ concentration, exposure duration and on their interaction, leading to complex response patterns. The use of a standard statistical approach to analyze those data led to underestimation of VZ effects on reproduction, whereas effects could reliably be analyzed by mixed-effect models. L. stagnalis may be among the most sensitive invertebrate species to VZ, a 21-day reproduction test allowing the detection of deleterious effects at environmentally relevant concentrations of the fungicide. These results thus reinforce the relevance of L. stagnalis as a good candidate species for the development of guidelines devoted to the risk assessment of EDs.

  5. PCR-RFLP Analysis of 28 SrDNA for Specification of Fasciola gigantica (Cobbold, 1855 in the Infected Lymnaea auricularia (Linnaeus, 1785 Snails from Northwestern Iran.

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    Mohammad Yakhchali

    2014-09-01

    Full Text Available Fasciolosis in livestock is a crucial concern in the globe, mainly due to its impact on human health. The aim of this study was to determine the rate of infection with Fasciola gigantica (Cobbold, 1855 larvae in the field-collected snails of Lymnaea auricularia (Linnaeus, 1785 from northwestern Iran using a molecular approach.A total of 6,759 pond snails were collected from 28 freshwater bodies in West Azarbaijan. PCR was performed to amplify a 618-bp fragment of the nuclear 28 SrRNA gene of Fasciola. The PCR products were digested by AvaII restriction enzyme to create restriction fragment length polymorphism (RFLP patterns specific for the detection of F. gigantica.Of the total collected snails 496 (7.34 % were L. auricularia, among which 4.64% (23 out of 496 were infected with a Fasciola species according to the PCR analysis. Only 2.22% (11 out of 496 of the infected snails were from the mountainous areas. The highest Fasciola infection rate recorded in the snails of a single site was 1.81% (9 out of 496 snails. Based on the RFLP pattern, F. gigantica accounted for 2.42% of the infection rates in the study sites.Application of PCR-RFLP was proven to be a useful approach for valid and robust detection of the infection with F. gigantica in its intermediate host snails. These findings may therefore be applicable for establishment of the control programs against dissemination of the infection in different regions.

  6. Impact of various salts on biology, physiology and tissue soluble proteins (SDS-PAGE) of Lymnaea natalensis and their infection with Fasciola gigantica miracidia.

    Science.gov (United States)

    Mahmoud, Moamena Bayoumi

    2006-08-01

    The effect of sublethal concentrations of magnesium sulphate (MgSo4), sodium chloride (NaCl), potassium chloride (KCl), calcium sulphate (CaSo4) and sodium carbonate (Na2Co3) on survival, fecundity, Lymnaea natalensis infection with Fasciola gigantica miracidia and the activities of certain enzymes in tissue homogenate of these snails were evaluated. Tissue soluble proteins of the snails were analyzed by SDS-PAGE. The results indicated that Na2Co3 was more toxic to L. natalensis than the other salts. Egg laying capacity was declined after two weeks of continuous exposure to Na2Co3 (0.38 eggs/snail/week) compared to (13.85 eggs/snail/week) for controls. The lowest infection rate was among snails exposed to MgSo4 (31.25%) with a significant variation from controls (64.28%). The salts supperssed cercarial production of infected snails (14.6 metacercariae/ snail/stimulant) at MgSo4 compared to (59.3 metacercariae/ snail/stimulant) for controls. The maintenance of L. natalensis in the salts solutions for four successive weeks reduced the total protein content in their tissues (13.2 mg/g) at Na2Co3 (100 ppm) compared to (21.47 mg/g) for controls. The activity of alkaline phosphatase was significantly reduced in treated snails than controls. The electrophoretic data revealed a common band between controls and treated snails with a molecular weight of 79.42 to 80.55 kDa. There were bands in treated snails but not in controls (41.2 & 45 kDa). A band was detected for snails treated with each salt but not with controls or the other treated groups (28.68 kDa at NaCl, 100.75 kDa at CaSo4 & 205 Kda at KCl).

  7. Calicophoron daubneyi and Fasciola hepatica: characteristics of natural and experimental co-infections of these digeneans in the snail Lymnaea glabra.

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    Vignoles, P; Titi, A; Mekroud, A; Rondelaud, D; Dreyfuss, G

    2017-01-01

    A retrospective study on different Lymnaea glabra samples collected from central France between 1993 and 2010 was carried out to determine the prevalence of natural co-infections with Calicophoron daubneyi and Fasciola hepatica, and to specify the composition of redial burdens. Experimental infections of L. glabra performed during the same period of time were also analysed to study metacercarial production of each digenean in co-infected snails. Controls were naturally or experimentally co-infected Galba truncatula. In natural co-infections, prevalence was 0.7% in L. glabra (186/25,128) and 0.4% in G. truncatula (137/31,345). Low redial burdens were found in these snails, with F. hepatica rediae significantly more numerous in L. glabra than in G. truncatula (7.5 per snail instead of 5.2). In contrast, the total numbers of C. daubneyi rediae in both lymnaeids were close to each other (4.3 and 3.0 rediae, respectively). In experimentally co-infected groups, prevalence was greater in G. truncatula than in the other lymnaeid (6.3% instead of 3.0%). Significantly shorter patent periods and lower metacercarial production for each digenean were noted in L. glabra than in G. truncatula. However, in both lymnaeids, the two types of cercariae were released during the same shedding waves and several peaks during the patent period were synchronous. In spite of a greater shell height for L. glabra, metacercarial production of both digeneans in co-infected snails was lower than that in G. truncatula, thus indicating a still incomplete adaptation between these French L. glabra and both parasites.

  8. Fasciola hepatica and Paramphistomum daubneyi: changes in prevalences of natural infections in cattle and in Lymnaea truncatula from central France over the past 12 years.

    Science.gov (United States)

    Mage, Christian; Bourgne, Henri; Toullieu, Jean-Marc; Rondelaud, Daniel; Dreyfuss, Gilles

    2002-01-01

    A retrospective study was carried out over a 10- to 12-year period to analyse the changes in prevalences of natural fasciolosis and paramphistomosis among cattle and snails in central France, and to determine the causes which had induced these changes. The prevalences of natural fasciolosis in cattle increased from 1990 to 1993 (13.6% to 25.2%) and diminished afterwards up to 1999 (at 12.6%). Those of natural paramphistomosis showed a progressive increase between 1990 and 1999 (from 5.2 to 44.7%). The prevalences of natural infections and the numbers of free rediae counted in the snails (Lymnaea truncatula) infected with F. hepatica did not show any significant variations over time. By contrast, the prevalences of natural paramphistomosis in snails significantly increased from 1989 to 1996 and remained afterwards in the same range of values (3.7-5.3%), while the number of free rediae significantly increased up to 2000 (from a mean of 6.5 to 13.8 rediae per infected snail, respectively). Three hypotheses may explain the increase of paramphistomosis in cattle and snails: a better quality of diagnosis for the detection of P. daubneyi eggs in veterinary analysis laboratories, the use of specific molecules in the treatment of cattle fasciolosis since 1993, and the lack of an effective treatment up to now against cattle paramphistomosis. Since the objective of most farmers in central France is to obtain the highest antiparasitic efficiency with a single treatment of cattle per year, it is reasonable to assume that the prevalence of bovine paramphistomosis will continue to increase in the future.

  9. Accumulation and detoxication responses of the gastropod Lymnaea stagnalis to single and combined exposures to natural (cyanobacteria) and anthropogenic (the herbicide RoundUp(®) Flash) stressors.

    Science.gov (United States)

    Lance, Emilie; Desprat, Julia; Holbech, Bente Frost; Gérard, Claudia; Bormans, Myriam; Lawton, Linda A; Edwards, Christine; Wiegand, Claudia

    2016-08-01

    Freshwater gastropods are increasingly exposed to multiple stressors in the field such as the herbicide glyphosate in Roundup formulations and cyanobacterial blooms either producing or not producing microcystins (MCs), potentially leading to interacting effects. Here, the responses of Lymnaea stagnalis to a 21-day exposure to non-MC or MC-producing (33μgL(-1)) Planktothrix agardhii alone or in combination with the commercial formulation RoundUp(®) Flash at a concentration of 1μgL(-1) glyphosate, followed by 14days of depuration, were studied via i) accumulation of free and bound MCs in tissues, and ii) activities of anti-oxidant (catalase CAT) and biotransformation (glutathione-S-transferase GST) enzymes. During the intoxication, the cyanobacterial exposure induced an early increase of CAT activity, independently of the MC content, probably related to the production of secondary cyanobacterial metabolites. The GST activity was induced by RoundUp(®) Flash alone or in combination with non MC-producing cyanobacteria, but was inhibited by MC-producing cyanobacteria with or without RoundUp(®) Flash. Moreover, MC accumulation in L. stagnalis was 3.2 times increased when snails were concomitantly exposed to MC-producing cyanobacteria with RoundUp(®), suggesting interacting effects of MCs on biotransformation processes. The potent inhibition of detoxication systems by MCs and RoundUp(®) Flash was reversible during the depuration, during which CAT and GST activities were significantly higher in snails previously exposed to MC-producing cyanobacteria with or without RoundUp(®) Flash than in other conditions, probably related to the oxidative stress caused by accumulated MCs remaining in tissues. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Impact of microcystin-producing cyanobacteria on reproductive success of Lymnaea stagnalis (Gastropoda, Pulmonata) and predicted consequences at the population level.

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    Lance, Emilie; Alonzo, Frederic; Tanguy, Marion; Gérard, Claudia; Bormans, Myriam

    2011-06-01

    Our previous studies showed that microcystin (MC)-accumulation in the gastropod Lymnaea stagnalis and effects on life-history traits (survival, growth, and fecundity) varied according to age, exposure pathway (MC-producing cyanobacteria or dissolved MC), and presence or not of additional non-toxic food. This study investigated effects of exposure to MC-producing cyanobacteria or to dissolved MC of parent and of parent and egg masses of L. stagnalis on hatching success, duration of embryonic development and neonate survival. Secondly, the potential impact of MC-producing cyanobacterial proliferations (blooms) on L. stagnalis population growth, depending on bloom frequencies and recovery duration of life traits after exposure, was evaluated using a modelling approach. Experimental results showed that embryonic development was shortened in case of parent exposure to toxic cyanobacteria. Parent and eggs exposure to dissolved MC extended embryonic development and reduced hatching percentage, suggesting a permeability of egg masses to MC. Whatever exposure, neonate survival was reduced. Neonates exposed to cyanobacteria accumulated MCs 24 h after hatching, suggesting very early cyanobacteria ingestion. Modelling results showed that L. stagnalis population growth was influenced by the recovery time of life-history traits after exposure. When setting the latest at 6 weeks according to previous experiments, a frequency of one to four blooms per year strongly affected population dynamics and induced up to a 80-weeks delay compared to control in time required for populations to grow from 1 to 1000 individuals. Results are discussed in terms of impact of intoxication pathways on parents, eggs and neonates, and on population dynamics of L. stagnalis.

  11. Distribution of Lymnaeidae (Mollusca: Pulmonata), intermediate snail hosts of Fasciola hepatica in Venezuela.

    Science.gov (United States)

    Pointier, J P; Noya, O; Alarcón de Noya, B; Théron, A

    2009-08-01

    An extensive malacological survey was carried out between 2005-2009 in order to clarify the exact number of lymnaeid species which may be intermediate hosts of Fasciola hepatica in Venezuela. Four species were discovered during this survey, including two local species: Lymnaea cubensis and Lymnaea cousini and two exotic species: Lymnaea truncatula and Lymnaea columella. The most common local species was L. cubensis which was found at 16 out of the 298 sampling sites. This species has a large distribution area throughout the Northern part of Venezuela and was encountered from sea level to an altitude of 1,802 m in state of Trujillo. The second local species L. cousini was collected at only two sites of the Andean Region at altitudes of 3,550 m and 4,040 m, respectively. The European L. truncatula was found at 24 sites all located in the states of Mérida and Táchira at an altitude varying between 1,540-4,000 m. The respective distribution areas of L. cubensis and L. truncatula do not appear to overlap, but more detailed malacological surveys are needed. The fourth lymnaeid species, L. columella was collected in a canal from Mérida at an altitude of 1,929 m and in an irrigation canal from the state of Guárico, at an altitude of 63 m. The role of these four lymnaeid species in the transmission of fascioliasis in Venezuela is discussed.

  12. Distribution of Lymnaeidae (Mollusca: Pulmonata, intermediate snail hosts of Fasciola hepatica in Venezuela

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    JP Pointier

    2009-08-01

    Full Text Available An extensive malacological survey was carried out between 2005-2009 in order to clarify the exact number of lymnaeid species which may be intermediate hosts of Fasciola hepatica in Venezuela. Four species were discovered during this survey, including two local species: Lymnaea cubensis and Lymnaea cousini and two exotic species: Lymnaea truncatula and Lymnaea columella. The most common local species was L. cubensis which was found at 16 out of the 298 sampling sites. This species has a large distribution area throughout the Northern part of Venezuela and was encountered from sea level to an altitude of 1,802 m in state of Trujillo. The second local species L. cousini was collected at only two sites of the Andean Region at altitudes of 3,550 m and 4,040 m, respectively. The European L. truncatula was found at 24 sites all located in the states of Mérida and Táchira at an altitude varying between 1,540-4,000 m. The respective distribution areas of L. cubensis and L. truncatula do not appear to overlap, but more detailed malacological surveys are needed. The fourth lymnaeid species, L. columella was collected in a canal from Mérida at an altitude of 1,929 m and in an irrigation canal from the state of Guárico, at an altitude of 63 m. The role of these four lymnaeid species in the transmission of fascioliasis in Venezuela is discussed.

  13. Composição e sazonalidade dos moluscos do alto rio Paraná, Brasil, e sua potencialidade como hospedeiros intermediários de digenéticos - DOI: 10.4025/actascibiolsci.v30i3.5018 Composition and seasonality of mollusks from the upper Paraná river, Brazil, and their potentiality as intermediate hosts for digeneans - DOI: 10.4025/actascibiolsci.v30i3.5018

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    Gilberto Cezar Pavanelli

    2008-10-01

    Full Text Available Este trabalho analisa a composição e a sazonalidade das espécies de moluscos potenciais hospedeiros intermediários de trematódeos digenéticos, bem como fornece informações a respeito das possíveis infecções por diplostomídeos nesta comunidade, em ambientes lênticos da planície de inundação do alto rio Paraná. Foram coletadas e analisadas dez espécies de moluscos, e houve nítida sazonalidade na densidade e abundância dos moluscos, correlacionada significativamente com a temperatura da água. Os maiores valores observados foram entre os meses de novembro de 2002 a fevereiro de 2003. Apenas Biomphalaria peregrina caracterizou-se como hospedeiro para Diplostomidae, pois nesta espécie foram encontradas 32 cercárias de Hysteromorpha triloba em março de 2003.This study analyzes the composition and seasonality of mollusk species as potential intermediate hosts for digenean trematodes, and also supplies information regarding the possible infections by diplostomidae in that community, in lentic environments of the upper Paraná river floodplain. Ten species of mollusks were collected and analyzed, with noticeable seasonality in the density and abundance of mollusks, significantly correlated with water temperature. The highest values observed were in the period between November 2002 and February 2003. Only Biomphalaria peregrina was characterized as a host for diplostomidae, given that 32 cercariae of Hysteromorpha triloba were found in this species in March 2003.

  14. Impact of the redox-cycling herbicide diquat on transcript expression and antioxidant enzymatic activities of the freshwater snail Lymnaea stagnalis

    Energy Technology Data Exchange (ETDEWEB)

    Bouetard, Anthony, E-mail: anthony.bouetard@rennes.inra.fr [INRA, UMR INRA-Agrocampus Ouest ESE 0985, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint-Brieuc, 35042 Rennes cedex (France); Besnard, Anne-Laure; Vassaux, Daniele; Lagadic, Laurent; Coutellec, Marie-Agnes [INRA, UMR INRA-Agrocampus Ouest ESE 0985, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint-Brieuc, 35042 Rennes cedex (France)

    2013-01-15

    The presence of pesticides in the environment results in potential unwanted effects on non-target species. Freshwater organisms inhabiting water bodies adjacent to agricultural areas, such as ditches, ponds and marshes, are good models to test such effects as various pesticides may reach these habitats through several ways, including aerial drift, run-off, and drainage. Diquat is a non-selective herbicide used for crop protection or for weed control in such water bodies. In this study, we investigated the effects of diquat on a widely spread aquatic invertebrate, the holarctic freshwater snail Lymnaea stagnalis. Due to the known redox-cycling properties of diquat, we studied transcript expression and enzymatic activities relative to oxidative and general stress in the haemolymph and gonado-digestive complex (GDC). As diquat is not persistent, snails were exposed for short times (5, 24, and 48 h) to ecologically relevant concentrations (22.2, 44.4, and 222.2 {mu}g l{sup -1}) of diquat dibromide. RT-qPCR was used to quantify the transcription of genes encoding catalase (cat), a cytosolic superoxide dismutase (Cu/Zn-sod), a selenium-dependent glutathione peroxidase (gpx), a glutathione reductase (gred), the retinoid X receptor (rxr), two heat shock proteins (hsp40 and hsp70), cortactin (cor) and the two ribosomal genes r18S and r28s. Enzymatic activities of SOD, Gpx, Gred and glutathione S-transferase (GST) were investigated in the GDC using spectrophoto/fluorometric methods. Opposite trends were obtained in the haemolymph depending on the herbicide concentration. At the lowest concentration, effects were mainly observed after 24 h of exposure, with over-transcription of cor, hsp40, rxr, and sod, whereas higher concentrations down-regulated the expression of most of the studied transcripts, especially after 48 h of exposure. In the GDC, earlier responses were observed and the fold-change magnitude was generally much higher: transcription of all target genes increased

  15. Molecular characterisation of Galba truncatula, Lymnaea neotropica and L. schirazensis from Cajamarca, Peru and their potential role in transmission of human and animal fascioliasis.

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    Bargues, M Dolores; Artigas, Patricio; Khoubbane, Messaoud; Ortiz, Pedro; Naquira, Cesar; Mas-Coma, Santiago

    2012-08-15

    Human and animal fascioliasis is emerging in many world regions, among which Andean countries constitute the largest regional hot spot and Peru the country presenting more human endemic areas. A survey was undertaken on the lymnaeid snails inhabiting the hyperendemic area of Cajamarca, where human prevalences are the highest known among the areas presenting a "valley transmission pattern", to establish which species are present, genetically characterise their populations by comparison with other human endemic areas, and discuss which ones have transmission capacity and their potential implications with human and animal infection. Therefore, ribosomal DNA ITS-2 and ITS-1, and mitochondrial DNA 16S and cox1 were sequenced by the dideoxy chain-termination method. Results indicate the presence of three, morphologically similar, small lymnaeid species belonging to the Galba/Fossaria group: Galba truncatula, Lymnaea neotropica and L. schirazensis. Only one combined haplotype for each species was found. The ITS-1, 16S and cox1 haplotypes of G. truncatula are new. No new haplotypes were found in the other two species. This scenario changes previous knowledge, in which only L. viator (= L. viatrix) was mentioned. Galba truncatula appears to be the most abundant, with high population densities and evident anthropophyly including usual presence in human neighbourhood. Infection by Fasciola hepatica larval stages were molecularly confirmed in two populations of this species. The nearness between G. truncatula populations presenting liver fluke infection and both human settings and schools for children, together with the absence of populations of other lymnaeid species in the locality, suggest a direct relationship with human infection. The geographical overlap of three lymnaeid species poses problems for epidemiological studies and control action. First, a problem in classifying lymnaeid specimens in both field and laboratory activities, given their transmission capacity

  16. Effects of chronic waterborne nickel exposure on growth, ion homeostasis, acid-base balance, and nickel uptake in the freshwater pulmonate snail, Lymnaea stagnalis.

    Science.gov (United States)

    Niyogi, Som; Brix, Kevin V; Grosell, Martin

    2014-05-01

    The freshwater pulmonate snail, Lymnaea stagnalis, is the most sensitive aquatic organism tested to date for Ni. We undertook a series of experiments to investigate the underlying mechanism(s) for this observed hypersensitivity. Consistent with previous experiments, juvenile snail growth in a 21-day exposure was reduced by 48% relative to the control when exposed to 1.3 μg l(-1) Ni (EC20 less than the lowest concentration tested). Ca(2+) homeostasis was significantly disrupted by Ni exposure as demonstrated by reductions in net Ca(2+) uptake, and reductions in Ca(2+) concentrations in the hemolymph and soft tissues. We also observed reduced soft tissue [Mg(2+)]. Snails underwent a significant alkalosis with hemolymph pH increasing from 8.1 to 8.3 and hemolymph TCO2 increasing from 19 to 22 mM in control versus Ni-exposed snails, respectively. Unlike in previous studies with Co and Pb, snail feeding rates were found to be unaffected by Ni at the end of the exposure. Snails accumulated Ni in the soft tissue in a concentration-dependent manner, and Ni uptake experiments with (63)Ni revealed a biphasic uptake profile - a saturable high affinity component at low exposure concentrations (36-189 nM) and a linear component at the high exposure concentrations (189-1,897 nM). The high affinity transport system had an apparent Km of 89 nM Ni(2+) and Vmax of 2.4 nmol g(-1)h(-1). This equates to a logK of 7.1, significantly higher than logK's (2.6-5.2) for any other aquatic organisms evaluated to date, which will have implications for Biotic Ligand Model development. Finally, pharmacological inhibitors that block Ca(2+) uptake pathways in snails did not inhibit Ni uptake, suggesting that the uptake of Ni does not occur via Ca(2+) uptake pathways. As with Cu and Pb, the exact mechanism for the significant disruption in Ca(2+) homeostasis and reduction in juvenile snail growth remains unknown.

  17. Toxinas paralizantes en moluscos bivalvos durante una proliferación de Gymnodinium catenatum Graham en la Bahía de La Paz, México Paralytic toxins in bivalve mollusks during a proliferation of Gymodinium catenatum Graham in Bahía de La Paz, Mexico

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    Francisco E. Hernández-Sandoval

    2009-12-01

    Full Text Available De febrero a marzo de 2007, se presentó una proliferación de Gymnodinium catenatum Graham en la Bahía de La Paz (México, con densidades de 6 x 10(5 a 2,39 x 10(6 cél. L-1. Durante este evento se determinó la concentración y el perfil de toxinas paralizantes en moluscos bivalvos (Pinna rugosa, Modiolus capax, Megapitaria squalida, Periglypta multicostata, Dosinia ponderosa y Megapitaria aurantiaca y en muestras de fitoplancton. También se obtuvieron algunos parámetros físicos y químicos. Los valores promedios de la temperatura superficial y del oxígeno disuelto fueron de 20.9 ± 0.7 °C y 6.9 ± 0.3 mg L-1, respectivamente. Las concentraciones promedios de nitritos, nitratos, amonio, fosfatos y silicatos fueron de 0.22 ± 0.05, 1.04 ± 0.33, 0.89 ± 0.88, 0.81 ± 0.76 y 8.85 ± 1.60 µM, respectivamente. El contenido de toxinas paralizantes en las muestras de arrastres de red variaron de 4.32 a 79.60 ng saxitoxina equivalente filtro-1, identificándose 8 toxinas, siendo la C1 y C2 las dominantes. Las máximas concentraciones de toxinas paralizantes en los moluscos fueron de 31.14, 37.74 y 25.89 µg STXeq. 100 g-1 en M. capax, P. rugosa y M. aurantiaca, respectivamente. Se dan a conocer las variaciones en el perfil de toxinas paralizantes en las diversas especies de moluscos.From February to March 2007 a harmful algae bloom of Gymnodinium catenatum Graham ocurred in Bahía de La Paz, Mexico, with cell densities from 6 x 10(5 to 2,39 x 10(6 cells L-1. During this event the toxin concentration and toxin profile of paralytic shellfish toxins in mollusks (Pinna rugosa, Modiolus capax, Megapitaria squalida, Periglypta multicostata, Dosinia ponderosa, and Megapitaria aurantiaca, and in phytoplankton samples were determined. Some physicochemical data were obtained. The average values of the surface temperature and dissolved oxygen were 20.9 ± 0.7 °C and 6.9 ± 0.3 mg L-1. The average concentrations of nitrites, nitrates, ammonium

  18. CAMBIOS EN EL TAMAÑO DE EXOESQUELETOS CALCÁREOS DE MOLUSCOS DURANTE EL HOLOCENO TARDÍO: ARQUEOMALACOLOGÍA DE CONCHEROS EN LA COSTA NORTE DE SANTA CRUZ, PATAGONIA ARGENTINA (Size Change of Calcareous Exoskeletons of Molluscs during the Late Holocene: Archaeomalacology of Shell Middens on the Northern Coast of Santa Cruz, Patagonia, Argentina

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    Heidi Hammond

    2016-12-01

    Full Text Available En la costa norte de Santa Cruz, Patagonia Argentina, los concheros son una de las evidencias arqueológicas de ocupación por cazadores-recolectores. Se realizaron estudios biométricos sobre exoesqueletos calcáreos de moluscos recuperados en concheros con el fin de evaluar la existencia de una tendencia/patrón de cambio en el tamaño a lo largo del tiempo. Los resultados permitieron reconocer una reducción en el tamaño medio de las conchas a lo largo del Holoceno tardío. Se discuten las implicancias paleoambientales, ecológicas y/o culturales. Finalmente, se avanza en la discusión sobre la dinámica de ocupación humana y el uso de los recursos. ENGLISH: On the northern coast of Santa Cruz, Patagonia, Argentina, shell middens form part of the archaeological evidence for hunter-gatherer occupation. We performed biometric studies on calcareous exoskeletons of molluscs recovered in shell middens in order to evaluate the existence of a trend or pattern of size change over time. The results allowed us to recognize a reduction in size change over the course of the late Holocene. We discuss the paleoenvironmental, ecological and/or cultural implications of these findings. Finally, we relate the discussion to the dynamics of human occupation and resource use.

  19. Movilidad, redes de intercambio y circulación de bienes en el sudoeste del Neuquén (Norpatagonia, Argentina: Los moluscos marinos del lago Traful Mobility, Exchange Networks And Circulation Of Goods In Southwestern Neuquén, Northern Patagonia, Argentina: The Marine Mollusks From Traful Lake

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    Mario Silveira

    2010-12-01

    Full Text Available Se determina la procedencia de fragmentos de moluscos marinos hallados en los aleros Los Cipreses y Lariviere, en el área del lago Traful, sur de la provincia de Neuquén. Estudios previos en áreas cercanas con mayor proximidad a la costa del océano Pacífico suponen que las piezas recuperadas evidencian contacto con grupos provenientes del lado occidental de la cordillera de Los Andes -Chile. En este trabajo se indica que parte de las valvas estudiadas corresponden a fósiles marinos o fluviales no identificados. Los fragmentos identificados corresponden al gasterópodo marino Adelomelon brasiliana procedente del Atlántico y al bivalvo Choromytilus chorus posiblemente del Pacífico. Estos datos, sumados a los recientes análisis sobre muestras de obsidiana procedentes de fuentes de aprovisionamiento del sudoeste neuquino que circularon grandes distancias hacia la costa atlántica, resaltan la complejidad y extensión de la movilidad humana y/o de las redes interregionales de intercambios.In this article the origin of fragments of marine shells found at Los Cipreses and Lariviere rock-shelters is presented. Consistent with studies by other authors in nearby areas in greater proximity to the Pacific coast, it was assumed that these fragments indicated contact with groups from the western side of the Chilean Andes. The results show that the shells correspond to marine or unknown fluvial fossils; a few pieces correspond to a marine gasteropod of great size, Adelomelon brasiliana, from the Atlantic Ocean and the bivalve Choromytilus chorus, probably from the Pacific. These data, and the recent analysis of samples of obsidian from sources located in southwestern Neuquén, which circulated far toward the Atlantic coast, highlight the complexity and extent of human mobility and interregional exchange networks.

  20. El uso de moluscos de agua dulce (Diplodon chilensis patagonicus en el sitio Angostura 1 (Departamento de General Conesa, Río Negro The use of freshwater mollusks (Diplodon Chilensis patagonicus at Angostura 1 site (General Conesa District, Río Negro province, Argentina

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    Luciano Prates

    2007-12-01

    Full Text Available En esta nota se presentan los resultados del estudio de las valvas de moluscos de agua dulce (Diplodon chilensis patagonicus recuperadas en el componente inferior del sitio arqueológico Angostura 1 (Departamento de General Conesa, provincia de Río Negro. Los atributos tenidos en cuenta para el análisis de los especímenes fueron: lateralidad de las valvas, tamaño, estado de fragmentación y presencia de periostraco; en forma secundaria se consideraron otras variables tales como evidencias de combustión y relación espacial con el resto de los materiales. A partir de estos datos y de la información contextual se propone la asociación de las valvas con el registro arqueológico del sitio (materiales líticos, cerámicos, óseos y vegetales y se discuten algunos procesos de formación vinculados con la actividad humana.This note presents the results of an analysis of freshwater mollusk shells (Diplodon chilensis patagonicus recovered from the lower cultural component of the Angostura 1 archaeological site (General Conesa District, Rio Negro Province, Argentina. Primarily, morphological features of this assemblage were analyzed, including: laterality, size, state of fracture, and the presence of periostracum. Secondarily, burning evidence and spatial relationships were considered. Site formation processes linked to human activity are discussed in light of these results and the contextual information from the site, i.e., mollusk shells associated with other archaeological remains (lithics, pottery, bones, and organic remains. It is proposed that the presence of freshwater mollusk shells in Angostura 1 site is linked to human activity.

  1. Verificação da resposta de miracídios de Schistosoma mansoni a substâncias provenientes de moluscos planorbídeos: pesquisa de substâncias quimiotáxicas Response of Schistosoma mansoni miracidia to snail substance: research on chemiotaxic substances

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    Beatriz de Camargo Brasio

    1985-04-01

    Full Text Available Foi testada a atividade miraxonal da água de condicionamento (SCW e da hemolinfa de Biomphalaria glabrata e de B. tenagophila frente a miracídios de Schistosoma mansoni das linhagens BH e SJ. Foram pesquisados e isolados alguns componentes de SCW. Com os componentes isolados de SCW e com a hemolinfa foram preparados blocos de ágar. Esses blocos, assim preparados, foram colocados frente a miracídios de S. mansoni para avaliação da atividade miraxonal. Foram detectadas diferenças entre a ação miraxonal da hemolinfa e das substâncias isoladas de SCW. Observaram-se diferenças significativas entre os efeitos miraxonais das duas espécies de moluscos pesquisados frente a miracídios das linhagens BH e SJ.Several substances isolated from SCW (snail conditioned water and from snail hemolymph were tested for a possible chemiotaxic effect on Schistosoma mansoni miracidia. Two strains of miracidia were considered (SJ and BH. Agar plates prepared with one of the substances were exposed to sixty miracidia for five minutes. The number of contacts and contacts with return were counted. Ten replications were made. Eight types (and four sub types of agar plates were prepared: normal water (control, SCW (Biomphalaria glabrata and B. tenagophila, hemolymph (B. glabrata and B. tenagophila and amonia, calcium, magnesium, sodium and potassium. Log-linear models were fitted to the data to study the proportions of attraction to each substance and to compare them. Any possible differences in proportions of attraction between the two S. mansoni strains were tested.

  2. Activity of Euphorbia splendens var. hislopii N.E.B. (Euphorbiaceae) latex against Lymnaea columella (Say, 1817) (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica, Linnaeus, 1758 (Trematoda: Fasciolidae). 2: limited field-testing.

    Science.gov (United States)

    de Vasconcellos, Mauricio Carvalho; de Amorim, Alziro

    2003-10-01

    The molluscicidal evaluation of Euphorbia splendens var. hislopii (Crown of thorns) against Lymnaea columella snails, intermediate host of Fasciola hepatica, in irrigation ditches of the Pisciculture Station at Universidade Federal Rural do Rio de Janeiro, was studied under limited field conditions. An aqueous solution of the latex at 5 mg/l was tested in two irrigation ditches (experimental and control ditches), after initial sampling of the snail population present. Twenty-four hours after application of the product, it was verified that 97.4% of free L. columella snails and 100% of snails of the same species captive in cages and used as sentinels at three points equidistant from the application site in the experimental ditch, died. For Biomphalaria tenagophila and Melanoides tuberculata snails, present in the experimental ditch, the mortality was 100%, for the species Pomacea spp. the mortality was 40%. No mortality was verified in the free mollusks, or in the sentinels in the ditch used as control. E. splendens var. hislopii latex is thus an efficient natural molluscicide, which may be used as an alternative control agent against L. columella.

  3. Activity of Euphorbia splendens var. hislopii N.E.B. (Euphorbiaceae latex against Lymnaea columella (Say, 1817 (Pulmonata: Lymnaeidae, intermediate host of Fasciola hepatica, Linnaeus, 1758 (Trematoda: Fasciolidae. 2: limited field-testing

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    Vasconcellos Mauricio Carvalho de

    2003-01-01

    Full Text Available The molluscicidal evaluation of Euphorbia splendens var. hislopii (Crown of thorns against Lymnaea columella snails, intermediate host of Fasciola hepatica, in irrigation ditches of the Pisciculture Station at Universidade Federal Rural do Rio de Janeiro, was studied under limited field conditions. An aqueous solution of the latex at 5 mg/l was tested in two irrigation ditches (experimental and control ditches, after initial sampling of the snail population present. Twenty-four hours after application of the product, it was verified that 97.4% of free L. columella snails and 100% of snails of the same species captive in cages and used as sentinels at three points equidistant from the application site in the experimental ditch, died. For Biomphalaria tenagophila and Melanoides tuberculata snails, present in the experimental ditch, the mortality was 100%, for the species Pomacea spp. the mortality was 40%. No mortality was verified in the free mollusks, or in the sentinels in the ditch used as control. E. splendens var. hislopii latex is thus an efficient natural molluscicide, which may be used as an alternative control agent against L. columella.

  4. Avaliação de resistência de clones de eucalipto às infecções naturais de Cryphonectria cubensis, com nova metodologia Evaluation of the resistance of Eucalyptus spp. clones naturally infected by Cryphonectria canker disease using a new methodology

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    Francisco Alves Ferreira

    2004-04-01

    Full Text Available Apresenta-se uma metodologia de avaliação de suscetibilidade ou resistência de clones de Eucalyptus grandis às infecções naturais da doença cancro, causado por Cryphonectria cubensis, no Estado do Amapá, com as árvores tendo cinco anos de idade. Os parâmetros usados relacionam-se, direta ou indiretamente, com a expressão dos mecanismos de defesa das árvores em nível de casca e lenho, quais sejam: a freqüência de incidência da doença; b freqüência de mortalidade por ela causada; e c freqüência de lesões e de cancros, com os seus respectivos posicionamentos, se basais e altos, e os seus aprofundamentos ou superficialidades nos troncos, bem como os seus tamanhos, se pequenos ou grandes. Para cada genótipo calculou-se um índice de doença por infecções naturais (IDIN. Para facilitar as comparações entre os genótipos testados, o IDIN do clone mais suscetível foi dividido por um fator, de modo a deixá-lo igual a 100. Esse mesmo fator dividiu também os IDINs dos demais genótipos. Finalmente, os clones foram agrupados nas categorias AS (altamente suscetíveis, MS (moderadamente suscetíveis, MR (moderadamente suscetíveis e AR (altamente resistentes ou imunes. Cada categoria agrupou genótipos cuja média de seus IDIN foi significativamente diferente da das demais, mediante o teste de contraste de médias.A new methodology is presented for susceptibility or resistance evaluation of Eucalyptus grandis clones, at five years of age, naturally infected by Cryphonectria canker in the state of Amapá, Brazil. The adopted parameters were frequencies of disease incidence, mortality, frequencies of lesions and cankers considering trunk position, depth, and size. These parameters are directly or indirectly related to the expression of defense mechanisms at bark and xylem levels. A disease index in percentage (IDIN was calculated for each clone. To facilitate comparing IDIN's of the genotypes, the IDIN of the most susceptible clone

  5. Acute toxicity, critical body residues, Michaelis-Menten analysis of bioaccumulation, and ionoregulatory disturbance in response to waterborne nickel in four invertebrates: Chironomus riparius, Lymnaea stagnalis, Lumbriculus variegatus and Daphnia pulex.

    Science.gov (United States)

    Leonard, Erin M; Wood, Chris M

    2013-06-01

    We investigated the bioaccumulation and acute toxicity (48 h or 96 h) of Ni in four freshwater invertebrate species in two waters with hardness of 40 (soft water) and 140 mg L(-1) as CaCO(3) (hard water). Sensitivity order (most to least) was Lymnaea stagnalis > Daphnia pulex > Lumbriculus variegatus > Chironomus riparius. In all cases water hardness was protective against acute Ni toxicity with LC(50) values 3-3.5× higher in the hard water vs. soft water. In addition, higher water hardness significantly reduced Ni bioaccumulation in these organisms suggesting that competition by Ca and Mg for uptake at the biotic ligand may contribute to higher metal resistance. CBR50 values (Critical Body Residues) were less dependent on water chemistry (i.e. more consistent) than LC(50) values within and across species by ~2 fold. These data support one of the main advantages of the Tissue Residue Approach (TRA) where tissue concentrations are generally less variable than exposure concentrations with respect to toxicity. Whole body Ni bioaccumulation followed Michaelis-Menten kinetics in all organisms, with greater hardness tending to decrease B(max) with no consistent effect on K(d). Across species, acute Ni LC(50) values tended to increase with both K(d) and B(max) values - i.e. more sensitive species exhibited higher binding affinity and lower binding capacity for Ni, but there was no correlation with body size. With respect to biotic ligand modeling, log K(NiBL) values derived from Ni bioaccumulation correlated well with log K(NiBL) values derived from toxicity testing. Both whole body Na and Mg levels were disturbed, suggesting that disruption of ionoregulatory homeostasis is a mechanism of acute Ni toxicity. In L. stagnalis, Na depletion was a more sensitive endpoint than mortality, however, the opposite was true for the other organisms. This is the first study to show the relationship between Na and Ni. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Molluscicidal action of the latex of Euphorbia splendens var. hislopii N.E.B. ("Christ's Crown") (Euphorbiaceae) against Lymnaea columella (Say, 1817) (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica Linnaeus, 1758 (Trematode: Fasciolidae): 1- test in laboratory.

    Science.gov (United States)

    de Vasconcellos, Mauricio Carvalho; de Amorim, Alziro

    2003-06-01

    The latex action of Euphorbia splendens var. hislopii (Christ's Crown) against snails Lymnaea columella, intermediate host of Fasciola hepatica, derived from irrigation ditches of the Station of Pisciculture at Universidade Federal Rural do Rio de Janeiro, was studied in the laboratory. Lab bioassays, using aqueous solutions of the latex, varying between 0.1 and 10 mg/l, have proven molluscicidal activity of the product collected on the same day the tests were performed, during the four seasons of the year, finding the following lethal concentrations (LC90): 1.51 mg/l in the spring; 0.55 mg/l in the summer; 0.74 mg/l in the fall and 0.93 mg/l in winter, after 24 h exposure of the snails, showing significant differences among the seasons of the year (ANOVA test, F = 11.01, G.L.= 3/33, p < 0.05), as well as among the concentrations (ANOVA test, F = 27.38, G.L.= 11/33, p < 0.05). In the summer, mortality reached 100% from concentration at 0.6 mg/l, the same during fall and in winter as of 1 mg/l, while in spring it only reached 100% mortality as of 2 mg/l. Mortality in the controls was low, reaching 5% in the summer and winter and 10% in the fall and spring. None of the samples died. During the assay, with an aqueous solution of the latex at a concentration of 5 mg/l, in order to check the time of duration of the product effect, in the laboratory, it was observed that the molluscicidal activity remained stable up to the 15th day after the beginning of the test with 100% mortality of L. columella, gradually losing its effect until the 23rd day, when we no longer observed animal mortality. In the control group, there was a random daily variation in mortality rate ranging 0-50% after 48 h of observation for 30 days.

  7. Molluscicidal action of the latex of Euphorbia splendens var. hislopii N.E.B. ("Christ's Crown" (Euphorbiaceae against Lymnaea columella (Say, 1817 (Pulmonata: Lymnaeidae, intermediate host of Fasciola hepatica Linnaeus, 1758 (Trematode: Fasciolidae: 1- test in laboratory

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    Vasconcellos Mauricio Carvalho de

    2003-01-01

    Full Text Available The latex action of Euphorbia splendens var. hislopii (Christ's Crown against snails Lymnaea columella, intermediate host of Fasciola hepatica, derived from irrigation ditches of the Station of Pisciculture at Universidade Federal Rural do Rio de Janeiro, was studied in the laboratory. Lab bioassays, using aqueous solutions of the latex, varying between 0.1 and 10 mg/l, have proven molluscicidal activity of the product collected on the same day the tests were performed, during the four seasons of the year, finding the following lethal concentrations (LC90: 1.51 mg/l in the spring; 0.55 mg/l in the summer; 0.74 mg/l in the fall and 0.93 mg/l in winter, after 24 h exposure of the snails, showing significant differences among the seasons of the year (ANOVA test, F = 11.01, G.L.= 3/33, p < 0.05, as well as among the concentrations (ANOVA test, F = 27.38, G.L.= 11/33, p < 0.05. In the summer, mortality reached 100% from concentration at 0.6 mg/l, the same during fall and in winter as of 1 mg/l, while in spring it only reached 100% mortality as of 2 mg/l. Mortality in the controls was low, reaching 5% in the summer and winter and 10% in the fall and spring. None of the samples died. During the assay, with an aqueous solution of the latex at a concentration of 5 mg/l, in order to check the time of duration of the product effect, in the laboratory, it was observed that the molluscicidal activity remained stable up to the 15th day after the beginning of the test with 100% mortality of L. columella, gradually losing its effect until the 23rd day, when we no longer observed animal mortality. In the control group, there was a random daily variation in mortality rate ranging 0-50% after 48 h of observation for 30 days.

  8. Comparative study between the effects of hyaluronic acid and acid galactan purified from eggs of the mollusk Pomacea sp in wound healing Estudo comparativo entre os efeitos do ácido hialurônico e do galactano acídico purificado dos ovos do molusco Pomacea sp na cicatrização de feridas

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    Ana Katarina Menezes da Cruz

    2004-01-01

    Full Text Available PURPOSE: To compare the effect of hyaluronic acid (HA and of AG on the healing of intestine wounds. METHODS: The semi-purified extract of the eggs of the mollusc was obtained by fractionation with ammonium sulfate and purification for ion-exchange chromatography. The obtained galactans were eluted in water (neutral galactan and in 0.1 and 0.2M NaCl (acidic galactans. The in vivo study was performed with 45 "Wistar" rats, separated in three groups (n=15. Solutions containing HA 1%, GA 1% or saline solution 0,9%, was placed topically on the sutures of wounds in the small intestine of the rats. After 05, 10 and 21 days the animals were sacrificed and biopsy of the healing tissue was done. RESULTS: The hystologic grading was more significant for HA and AG groups when compared to the group C. AG stimulated the appearance of macrophages, giant cells and increase in the concentration of collagen in the area of the wound when compared to HA. CONCLUSION: The topical use of GA in intestinal wounds promoted the anticipation of events that are important in the wound healing.OBJETIVO: Comparar o efeito de ácido hialurônico (AH e do GA na cicatrização de feridas intestinais. MÉTODOS: O extrato semipurificado dos ovos do molusco foi obtido por fracionamento com sulfato de amônio e purificação por cromatografia de troca-iônica. Os galactanos obtidos foram eluídos em água (galactano neutro e em 0.1 e 0.2M NaCl (galactanos acídicos. O estudo em vivo foi executado com 45 ratos Wistar, separados em três grupos (n=15. Soluções contendo AH 1%, GA 1% ou solução salina 0,9%, foram aplicadas topicamente nas suturas das feridas longitudinais localizadas no intestino delgado dos ratos. Depois de 05, 10 e 21 dias os animais foram sacrificados e biópsias dos tecidos cicatrizados foram realizadas. RESULTADOS: A graduação histológica foi mais significante para os grupos do AH e GA quando comparado ao grupo C. O GA estimulou o aparecimento de macr

  9. Spatial distribution of bivalve mollusc assemblages in the upwelling ecosystem of the continental shelf of Cabo Frio, Rio de Janeiro, Brazil Distribuição espacial das associações de moluscos bivalves na plataforma continental do ecossistema da ressurgência de Cabo Frio, Rio de Janeiro, Brasil

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    Abilio Soares-Gomes

    2005-03-01

    Full Text Available Bivalve mollusks of the continental shelf of Cabo Frio upwelling ecosystem were sampled monthly from February 1986 to February 1987 along a 30 to 60 m depth gradient. Mactra petiti Orbigny, 1846, and Tellina gibber Ihering, 1907 were constant species in 30 m; Nucula puelcha Orbigny, 1846, Adrana patagonica Orbigny, 1846, T. petitiana, T. gibber, and Corbula patagonica Orbigny, 1846 in 45 m; and N. puelcha, T. gibber, C. patagonica, and C. caribaea in 60 m. The number of rare species was similar along the depth gradient, ranging from six to ten species. The number of common species was higher in 60 m than in 30 m. Some species showed a continuous distribution but changed the frequency and abundance along the bathymetric gradient. The mean density was higher in 45-60 m than in 30 m, ranging from 15.6 ind.m-2, in 30 m, to 68.1 ind.m-2, in 60 m. There was no seasonal change in density nor in the taxocene structure during the studied period. On the other hand, the bivalve assemblage was spatially structured along the depth gradient, showing consistent changes from 30 to 60 m depths. Diversity and richness also follow this distribution pattern.Os moluscos bivalves da plataforma continental do ecossistema da ressurgência do Cabo Frio foram amostrados mensalmente de fevereiro de 1986 a fevereiro de 1987, entre 30 a 60 m de profundidade. Mactra petiti e Tellina gibber Ihering, 1907 foram espécies constantes a 30 m; Nucula puelcha Orbigny, 1846, Adrana patagonica Orbigny, 1846, T. petitiana, T. gibber e Corbula patagonica Orbigny, 1846 a 45 m; e N. puelcha, T. gibber, C. patagonica e C. caribaea a 60 m. O número de espécies raras foi similar nas diferentes profundidades, variando entre seis a dez espécies. O número de espécies comuns foi maior a 60 m que a 30 m. Algumas espécies apresentaram distribuição contínua porém, com variação na freqüência e abundância ao longo do gradiente batimétrico. A densidde média foi maior a 45-60 m do que

  10. First records of freshwater molluscs from the ecological reserve El Edén, Quintana Roo, México Primeros registros de moluscos dulceacuícolas de la Reserva Ecológica El Edén, Quintana Roo, México

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    Roberto Cózatl-Manzano

    2007-12-01

    Full Text Available The diversity of the freshwater molluscs at El Edén was unknown. This is the first treatment of them, allowing us to compare spatial and temporal species distribution. Eleven species of freshwater molluscs were found in 2 surveys carried in March (dry season and September (rainy season 1998 at the reserve El Edén. A total of 266 individuals were collected; 8 pulmonates, Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis, and Planorbula armigera; 2 prosobranchs, Pyrgophorus sp. and Pomacea flagellata; and one bivalve, Musculium transversum. Pulmonata dominate over Prosobranchia species in diversity. No significant differences were observed in diversity between dry and rainy seasons. However, species abundance recorded in both seasons was very low, probably due to a combination of inadequate food resources and disadvantageous climate (periodic conditions of drought and flooding. Further studies using a combination of different sampling methods and more frequent samplings are needed to confirm or identify these factors. We suggest that future studies should focus on cultivation of species with economic potential such as the apple snail Pomacea flagellata.La diversidad de moluscos dulceacuícolas de la Reserva Ecológica El Edén se desconocía; este estudio constituye su primer registro. Asimismo, esta investigación permite comparar la distribución espacial y temporal de las especies registradas. Las recolectas se efectuaron en marzo (temporada de sequía y septiembre (lluvia de 1998. Se registran 11 especies (266 individuos en total, 8 pulmonados: Mayabina spiculata, Mexinauta impluviatus, Physa sp., Biomphalaria havanensis, Drepanotrema lucidum, Drepanotrema kermatoides, Planorbella (Pierosoma trivolvis y Planorbula armigera; dos prosobranquios: Pyrgophorus sp. y Pomacea flagellata, y un bivalvo: Musculium transversum. Los pulmonados

  11. Molluscicidal effect of WPN and MNSC on Lymnaea%氯硝柳胺乙醇胺盐可湿性粉剂和四聚·杀螺胺悬浮剂杀灭椎实螺实验研究

    Institute of Scientific and Technical Information of China (English)

    王尚位; 王海英; 罗秉荣; 李科荣; 刘榆华; 赵申华; 杨华; 李天美

    2013-01-01

    目的 观察50%氯硝柳胺乙醇胺盐可湿性粉剂(WPN)和26%四聚·杀螺胺悬浮剂(MNSC)杀灭椎实螺效果.方法 将WPN和MNSC分别配制成有效成分浓度为0.06、0.13、0.25、0.50、1.00、2.00 mg/L和4.00 mg/L的溶液,在实验室浸泡椎实螺成螺,统计椎实螺死亡率并计算半数致死浓度(LC50值).采用有效成分浓度分别为0.03、0.06、0.13、0.25、0.50、1.00g/m2和2.00 g/m2的WPN和MNSC开展室内喷洒杀灭椎实螺试验,统计椎实螺死亡率并计算计算LC50值.分别配制WPN和MNSC有效成分浓度为1.00、0.50、0.25、0.13 mg/L的溶液,分组投放椎实螺,观察不同时间椎实螺上爬情况.结果 WPN浸杀48 h和72 h的LC50值分别为0.93 mg/L和0.64 mg/L,MNSC浸杀48 h和72 h的LC50值分别为0.74 mg/L和0.51 mg/L; WPN和MNSC有效成分浓度>1.00 g/m2时,喷洒3d后椎实螺死亡率均达100%;在有效成分浓度为1.00 mg/L的WPN和MNSC药液中,未见椎实螺上爬,但在低浓度药液中有少量椎实螺上爬.结论 WPN和MNSC均有杀灭椎实螺效果,且均可抑制椎实螺上爬.现场开展杀灭椎实螺工作时,浸杀法应采用WPN和MNSC有效成分浓度2.00 mg/L浸杀48 h以上为宜,喷洒法应采用有效成分含量1.00 g/m2喷洒3d为宜.%Objective To evaluate the molluscicidal effect of wettable powder of 50% niclosamide ethanolamide salt (WPN) and suspension concentrate of 26% metaldehyde and niclosamide (MNSC) on Lymnaea. Methods WPN and MNSC were prepared as a series of solutions containing the active ingredient concentrations of 0.06, 0.13, 0.25, 0.50, 1.00, 2.00 mg/L and 4.00 mg/L, and the adult Lymnaea snails were soaked in the above mentioned series of solutions in the laboratory, and the LC50 values were calculated. The doses of active ingredient concentrations of 0.03, 0.06,0.13, 0.25, 0.50, 1.00 g/m2 and 2.00 g/m2 of WPN and MNSC were adopted to spray on Lymnaea snails in the laboratory, and the LC50 values were calculated. A series of

  12. Density and body size of the larval stages of the invasive golden mussel (Limnoperna fortunei in two neotropical rivers Densidade e tamanho dos estágios larvais do molusco invasor mexilhão dourado (Limnoperna fortunei em dois rios neotropicais

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    Vivianne Eilers

    2011-09-01

    populacionais e tamanho dos diferentes estágios das larvas planctônicas do molusco invasor mexilhão dourado (Limnoperna fortunei, nos rios Paraguai e Miranda; MÉTODOS: O estudo foi realizado entre fevereiro de 2004 e janeiro de 2005. Amostras mensais de plâncton foram acompanhadas pela análise de características físicas, químicas e biológicas da água; RESULTADOS: O rio Miranda apresentou maiores valores de cálcio, pH, alcalinidade, condutividade e fósforo total. A densidade das larvas variou entre 0-24 indivíduos.L-1 no rio Paraguay, com o máximo em março de 2004, enquanto no rio Miranda, a densidade variou entre 0-9 indivíduos.L-1, com o máximo em fevereiro de 2004. Larvas não foram encontradas nos meses mais frios, maio e junho. Nenhuma correlação significativa foi encontrada entre as características ambientais e densidades das larvas. Somente larvas com valvas foram encontradas. As formas "D" e veliger foram mais abundantes; a forma umbonada foi rara no rio Miranda. Valores médios dos tamanhos dos estágios "D", veliger e umbonada foram, respectivamente, 111, 135 e 152 µm, no rio Paraguai, e 112, 134 e 154 µm no rio Miranda. A análise de Componentes Principais indicou relações positivas entre o comprimento da forma "D" e a relação sólidos suspensos inorgânicos:orgânicos, enquanto relações negativas foram indicadas entre o comprimento da forma "D" e concentrações de cálcio e clorofila-; CONCLUSÕES: As larvas foram encontradas no plâncton durante a maior parte do ano, com a exceção dos meses mais frios. A densidade de larvas e o tamanho foram similares nos dois rios. Não foram registrados efeitos positivos da disponibilidade de alimento ou da concentração de cálcio sobre o tamanho das larvas. Esta espécie pode ser adaptada a crescer em ambientes com altas concentrações de sedimentos.

  13. Quantitative fidelity of recent freshwater mollusk assemblages from the Touro Passo River, Rio Grande do Sul, Brazil Fidelidade quantitativa de associações de moluscos límnicos recentes na bacia do rio Touro Passo, Rio Grande do Sul, Brasil

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    Alcemar R. Martello

    contribuições ao conhecimento sobre a fidelidade quantitativa de associações de moluscos recentes em rios subtropicais. Tanatocenoses e biocenoses foram estudadas em seções retilínea e meandrante tendendo a anastomosada, no curso médio do rio Touro Passo, um tributário de 4ª ordem do rio Uruguai, localizado no extremo oeste do Rio Grande do Sul. As amostragens foram realizadas por meio de quadrats de 5 m², cinco em cada seção, amostrando-se um total de 50 m². Também foram feitas amostragens em um ambiente lêntico, com comunicação intermitente com o Touro Passo, objetivando detectar a existência de transporte de comunidades lênticas para o interior do rio. Os resultados obtidos mostram que, apesar da freqüente oscilação do nível da água, a biocenose do Touro Passo apresenta uma alta fidelidade ecológica e sofre pouca influência de espécies de ambientes lênticos. A composição taxonômica e características de estrutura de comunidades, especialmente as espécies dominantes, refletem, ainda, diferenças ecológicas relacionadas às duas seções amostradas, como a maior complexidade de habitats da estação meandrante. Quanto à fidelidade quantitativa, 60% das espécies encontradas vivas também foram encontradas mortas e 47,3% das espécies encontradas mortas também foram encontras vivas em escala de rio. Porém, 72% dos exemplares coletados mortos são representantes de espécies encontradas vivas. Essa percentagem alta pode estar relacionada à boa correlação entre o ranking de dominância das associações vivas e mortas e, conseqüentemente, as espécies dominantes das tanatocenoses podem ser utilizadas para inferir características ecológicas das biocenoses. Todos os índices analisados variaram muito em escala local (quadrat e seus valores são mais aproximados aos de outros, registrados em estudos prévios, apenas quando analisados em escala mais ampla (seção, área total.

  14. Fasciola hepatica (Trematode: Fasciolidae) en la zona alta de Mérida, Venezuela (Fasciola hepatica (Trematode: Fasciolidae) in zone high of Mérida, Venezuela)

    OpenAIRE

    Nieves,E.; Rondon, M.; Zamora, E.; Salazar M

    2005-01-01

    Se realizó un estudió sobre la presencia de Fasciola hepática en la finca “El Joque” vía La Azulita, Estado Mérida, Venezuela. Un foco natural de fasciolasis fue verificado por la presencia de formas larvales en los caracoles hospedadores intermediarios y por examen coprológico en los bovinos de la finca. Detectandose la presencia de moluscos en todas las áreas muestreadas de la finca, de los cuales, el 77% resultó ser del Genero Lymnaea (Pulmonata: Lymnaeidae), se determinó una prevalencia ...

  15. О статусе материнской спороцисты Fasciola hepatica Linnaeus, 1758 в тканях Lymnaea truncatula Muller, 1774

    OpenAIRE

    Соколина, Флюра

    2007-01-01

    Морфофункциональные механизмы адаптогенеза системы «паразит-хозяин» мало изучены. В статье изложены данные, полученные при гистологических исследованиях тканей Lymnaea truncatula Muller, 1774 зараженных Fasciola hepatica Linnaeus, 1758, возбудителем заболевания печени человека и животных. Уточнены места проникновения и локализации личинок фасциолы на стадии материнской спороцисты....

  16. Levantamento malacológico da Bacia Hidrográfica do Lago Soledade, Ouro Branco, (Minas Gerais, Brasil Malacological survey at the Soledade Lake, in Ouro Branco (Minas Gerais, Brazil

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    Roney Elias da Silva

    1994-10-01

    Full Text Available Em estudo malacológico realizado na Bacia Hidrográfica do Lago Soledade, Ouro Branco, MG, no período de setembro de 1986 a março de 1991, foram coletados 46.579 moluscos, representados por 07 espécies de 05 famílias. Foram coletados 39.176 exemplares de Biomphalaria tenagophila, 1.296 de B. glabrata, sete exemplares de Drepanotrema cimex, 2.527 de Physa sp, 417 de Lymnaea sp, 92 de Pomacea haustrum e, a partir de março/1990, 3.064 exemplares de Melanoides tuberculata (Melanniidae = Thiaridae. Dos moluscos que apresentaram positividade para diversas larvas de trematódeos, quatro exemplares de B. tenagophila estavam positivos para S. mansoni.A malacological survey was carried out at the Soledade Lake, in Ouro Branco, State of Minas Gerais, for the period 1986-1991. A total amount of 46,579 mollusks was collected, and among them seven species corresponding to five families could be found, as follows: 39,176 specimens of Biomphalaria tenagophila; 1,296 B. glabrata; 7 Drepanotrema cimex; 2,527 Physa sp; 417 Lymnaea sp; 92 Pomacea hastrum, and 3,064 specimens of Melanoides tuberculata (Melanniidae=Thiaridae were collected from March/1990 onwards. Four specimens of B. tenagophila were found to be positive for Schistosoma mansoni.

  17. Fascioliasis of livestock and snail host for Fasciola in the Altiplano Region of Bolivia.

    Science.gov (United States)

    Ueno, H; Arandia, R; Morales, G; Medina, G

    1975-01-01

    Fascioliasis caused by Fasciola hepatica was a serious problem for sheep and alpacas in the Altiplano Region of Bolivia. In some provinces close to Lake Titicaca, the raising of sheep was forced to discontinue, because infection with the fluke made it unprofitable and almost impossible. It was proved that in the Altiplano Region, two species of freshwater snails, Lymnaea viatrix and L. cubensis var., served as intermediate hosts for F. hepatica. In some subtropical areas of Bolivia, these snails could not be found, although other Lymnaea sp. was widely distributed there. As it is possible for Lymnaea sp. to be intermediate host for the fluke, further studies are required on the identification. Acute fascioliasis of sheep occurred in the Altiplano Region principally during a period from May to July, or the dry season. In some areas, the mortality rate of infected sheep was roughly estimated as 15 to 25% annually. Contamination with Fasciola metacercariae of herbage and semi-aquatic plants grown in a swamp in one of these areas was biologically assessed, using guinea pigs. Plants of Compositae and Eleocharis sp. were contaminated most intensely and those of Senicio sp. and Vallisneria sp. carried a fairly large number of cysts, while plants of Scirpus sp. and Ranunclaceae carried only a few cysts. No signs of Fasciola infection were observed in any animal given the plants of Liliaceae.

  18. Epidemiology and population biology of pseudoperonospora cubensis: a model system for management of downy mildews

    Science.gov (United States)

    The resurgence of cucurbit downy mildew has dramatically influenced production of cucurbits and disease management systems at multiple scales. Long-distance dispersal is a fundamental aspect of epidemic development that influences the timing and extent of disease outbreaks. Dispersal potential of th...

  19. Centrocestus formosanus (Opisthorchiida: Heterophyidae como causa de muerte de alevines de tilapia gris Oreochromis niloticus (Perciforme: Cichlidae en el Pacífico seco de Costa Rica

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    Donald Arguedas Cortés

    2010-12-01

    Full Text Available Centrocestus formosanus es un parásito trematodo zoonótico originario de Asia asociado con muertes de peces principalmente de cultivo. 907 moluscos provenientes de estanques sembrados con tilapias, seleccionados uno por provincia fueron identificados al nivel taxonómico especifico. Se identificaron cuatro gastrópodos y un bivalvo: M. tuberculata, M. turricula, P. flagellata, H. cubensis y A. luteola. Se reporta, por primera vez, la presencia de dos especies de moluscos en Costa Rica. Se identificaron siete morfotipos de cercarias parasitando las cinco especies de moluscos encontradas. En la segunda exposición experimental se demostró que el morfotipo parapleurolofocercus encontrado en M. tuberculata concuerda con el hallazgo de C. formosanus en alevines de tilapia, después del examen clínico, anatomopatológico y parasitológico realizado a los alevines expuestos. Las metacercarias fueron extraídas del quiste utilizando microagujas y micropinzas lavadas en solución salina fisiológica (0.65%, fijadas en formol caliente al 4% y después esquematizadas con una cámara clara adaptada a un microscopio fotónico, estimándose una abundancia e intensidad media de 1018-1027 digeneos por branquia en cada pez parasitado, determinándose así el hospedador intermediario primario y secundario del parásito. En el presente trabajo se reporta por primera vez Centrocestus formosanus en Costa Rica.

  20. Phylogeography and genetic divergence of some lymnaeid snails, intermediate hosts of human and animal fascioliasis with special reference to lymnaeids from the Bolivian Altiplano.

    Science.gov (United States)

    Jabbour-Zahab, R; Pointier, J P; Jourdane, J; Jarne, P; Oviedo, J A; Bargues, M D; Mas-Coma, S; Anglés, R; Perera, G; Balzan, C; Khallayoune, K; Renaud, F

    1997-04-15

    A population genetic study using starch gel electrophoresis was performed on populations of several species of lymnaeid snails acting as intermediate hosts for Fasciola hepatica (Trematoda, Plathyhelminth). Lymnaea viatrix was collected in 16 sites from the Bolivian Northern Altiplano. L. cubensis were obtained in one site from Venezuela, one site from Guadeloupe, three sites from Cuba and one site from the Dominican Republic. L. truncatula were collected in one site from France, one from Portugal and one from Morocco. Multilocus enzyme electrophoresis (MEE) were determined for 282 snails at 18 loci. A complete monomorphism was encountered at each geographic site. However, among these 18 loci, 13 are polymorphic and low and high levels of genetic divergence were observed between samples. Two genotypic groups can be differentiated by their multilocus genotypes. The western genotypic group associates together samples from Venezuela, Guadeloupe, Cuba and Dominican Republic (L. cubensis) while samples from France, Portugal and Morocco (L. truncatula) belong to the eastern genotypic group. Surprisingly, the Northern Bolivian Altiplano populations (L. viatrix) do not present any genetic divergence with the Portuguese sample. Therefore, the Bolivian snails belong entirely to the eastern genetic group. Within each group slight genetic divergences were observed. These results strongly support the European origin of the lymnaeid snails from the Northern Bolivian Altiplano.

  1. Chronic effects of CuO Nanoparticles on Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Falk, Nina; Zwicky, Julie; Rewentlow, Julie

    Due to their small size and high surface-to-volume ratio, the properties and reactivity of NPs are different from those of their bulk forms. However, these properties might cause different behaviour and effects in the environment and investigations of possible nano specific effects are thus highl...... relevant. Investigation of the long-term effects of CuO NPs on growth, mortality and precopulation of Hyalella azteca compared to CuCl2 and to further examine possible delayed effects and ability to recover from Cu exposure....

  2. Infecção experimental de Lymnaea columella por Fasciola hepatica Laboratory infection of Fasciola hepatica in Lymnaea columella

    Directory of Open Access Journals (Sweden)

    Marlene Tiduko Ueta

    1980-03-01

    Full Text Available Os ovos de F. hepatica recolhidos em bilis de boi, fezes e em bilis de coelhos foram incubados a temperatura ambiente, dando origem a miracídios após 9 a 13 dias. Com estes miracídios recém-eclodidos foram infectados experimentalmente 233 exemplares de L. columella medindo 5,0 a 11,0 mm de comprimento. Das limneas infectadas apenas 3% sobreviveram até o desenvolvimento completo das cercarías. Houve formação de 190 a 1150 metacercárias entre o 46° ao 54° dia de infecção. Vários camundongos, ratos, cobaias e coelhos foram infectados com metacercárias de diferentes idades, mas somente os coelhos eliminaram ovos nas fezes 78 dias depois. Com a morte dos coelhos foram recuperados vermes adultos.F. hepatica eggs from infected cattle and rabbits were incubated at room temperature, hatching miracidia within 9 to 13 days. Newly hatched miracidia were used to infect 233 L. columella 5 to 11 mm long. Only 3% of the infected snails survived until the cercariae fully developed. From 190 to 1150 metacercariae developed within 46 to 54 days. Laboratory-bred mice, rats, Guinea pigs, and rabbits were fed metacercariae of different ages, but only the rabbits eliminated eggs in their feces, and this 78 days after infection, Adult worms were recovered after death of the rabbits.

  3. Сезонная динамика численности и зараженности моллюсков Lymnaea truncatula личинками Fasciola hepatica в условиях Таджикистана

    OpenAIRE

    Закирова, С.

    2012-01-01

    Изучена сезонная динамика численности и зара-женности моллюсков Lymnaea truncatula личинками Fasciola hepatica в условиях северной части Таджики-стана. Максимальная численность моллюсков L. truncatula установлена в августе-сентябре-октябре 37,4±2,7 экз./м2 при 7,3%-ной зараженности их личин-ками F. hepatica...

  4. A new baseline for fascioliasis in Venezuela: lymnaeid vectors ascertained by DNA sequencing and analysis of their relationships with human and animal infection

    Science.gov (United States)

    2011-01-01

    Background Human and animal fascioliasis poses serious public health problems in South America. In Venezuela, livestock infection represents an important veterinary problem whereas there appear to be few human cases reported, most of which are passively detected in health centres. However, results of recent surveys suggest that the situation may be underestimated in particular areas. To obtain a baseline for future fascioliasis assessment, studies were undertaken by means of rDNA ITS-2 and ITS-1 and mtDNA cox1 sequencing to clarify the specific status of Venezuelan lymnaeids, their geographical distribution and fascioliasis transmission capacity, by comparison with other American countries and other continents. Results Results obtained completely change the lymnaeid scenario known so far. The relatively rich lymnaeid fauna of Venezuela has been proven to include (i) Lymnaea meridensis and L. neotropica as the only native members, (ii) L. cubensis and Pseudosuccinea columella introduced from the Caribbean area, and (iii) Galba truncatula and L. schirazensis introduced from the Old World. The absence of representatives of the stagnicoline and Radix groups is remarkable. Four species are fascioliasis vectors: G. truncatula, L. cubensis and L. neotropica, which have the capacity to give rise to human endemic areas, and P. columella, which is a source of animal infection and is responsible for the spread of disease. Vector capacity in the apparently highland endemic L. meridensis is to be confimed, although may be expected given its phylogenetic relationships. Similarly as elsewhere, the non-transmitting L. schirazensis has been confused with L. cubensis, also with G. truncatula and possibly with L. neotropica. Conclusions The new scenario leads to the re-opening of many disease aspects. In Venezuela, altitude appears to be the main factor influencing fascioliasis distribution. Human infection shows an altitude pattern similar to other Andean countries, although a

  5. Centrocestus formosanus (Opisthorchiida: Heterophyidae como causa de muerte de alevines de tilapia gris Oreochromis niloticus (Perciforme: Cichlidae en el Pacífico seco de Costa Rica

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    Donald Arguedas Cortés

    2010-12-01

    Full Text Available Centrocestus formosanus es un parásito trematodo zoonótico originario de Asia asociado con muertes de peces principalmente de cultivo. 907 moluscos provenientes de estanques sembrados con tilapias, seleccionados uno por provincia fueron identificados al nivel taxonómico especifico. Se identificaron cuatro gastrópodos y un bivalvo: M. tuberculata, M. turricula, P. flagellata, H. cubensis y A. luteola. Se reporta, por primera vez, la presencia de dos especies de moluscos en Costa Rica. Se identificaron siete morfotipos de cercarias parasitando las cinco especies de moluscos encontradas. En la segunda exposición experimental se demostró que el morfotipo parapleurolofocercus encontrado en M. tuberculata concuerda con el hallazgo de C. formosanus en alevines de tilapia, después del examen clínico, anatomopatológico y parasitológico realizado a los alevines expuestos. Las metacercarias fueron extraídas del quiste utilizando microagujas y micropinzas lavadas en solución salina fisiológica (0.65%, fijadas en formol caliente al 4% y después esquematizadas con una cámara clara adaptada a un microscopio fotónico, estimándose una abundancia e intensidad media de 1018-1027 digeneos por branquia en cada pez parasitado, determinándose así el hospedador intermediario primario y secundario del parásito. En el presente trabajo se reporta por primera vez Centrocestus formosanus en Costa Rica.Centrocestus formosanus (Opisthorchiida: Heterophyidae as a cause of death in gray tilapia fry Oreochromis niloticus (Perciforme: Cichlidae in the dry Pacific of Costa Rica. Centrocestus formosanus is a zoonotic trematode from Asia and has been mainly associated as cause of death of cultured fish. To identify pathogen trematode species in tilapia fry (Oreochromis niloticus and to determine mollusks hosting these parasites, freshwater mollusks were collected from tilapia cultured ponds and experimental infections were carried out with tilapia fries and

  6. Using next-generation sequencing to develop molecular diagnostics for Pseudoperonospora cubensis, the cucurbit downy mildew pathogen

    Science.gov (United States)

    Advances in Next Generation Sequencing (NGS) allow for rapid development of genomics resources needed to generate molecular diagnostics assays for infectious agents. NGS approaches are particularly helpful for organisms that cannot be cultured, such as the downy mildew pathogens, a group of biotrop...

  7. Los moluscos bivalvos : Aportes para su enseñanza: teoría-métodos

    OpenAIRE

    Darrigran, Gustavo

    2013-01-01

    En este libro se considera a la biodiversidad como la variedad y variabilidad de los seres vivos y de los sistemas ecológicos que ellos integran. Por lo tanto, son tres los componentes de la diversidad biológica organizados en tres niveles: el de las especies (variedad), que son conjuntos de organismos afines capaces de reproducirse entre sí; el de los genes (variabilidad), que constituyen las bases moleculares de la herencia y el de los ecosistemas (sistemas ecológicos), que son complejos fu...

  8. Glándula pediosa de moluscos terrestres y sus implicancias evolutivas, con énfasis en Megalobulimus

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    Victor Borda

    2011-05-01

    Full Text Available Se describe la anatomía de la glándula pediosa de cinco especies de Megalobulimus (Megalobulimidae, y son comparadas con gastrópodos pulmonados Succineidae, Orthalicidae, Helicidae y Veronicellidae. Una sinapomorfía considerada para el clado Stylommatophora es la presencia de una membrana que aísla a la glándula pediosa de la cavidad visceral. Las especies estudiadas mostraron un grado variable de sujeción de la glándula al pie, desde apenas sujeta por escasa fibras (Megalobulimus hasta aquella totalmente aislada por una membrana (Cantareus pasando por grados intermedios (Succinea y Bostryx. La glándula pediosa en la seudobabosa Heterovaginia limayana (Systellommatophora no está adherida al piso de la cavidad visceral. En Megalobulimus, la parte glandular es voluminosa y pende del techo de la cápsula, a diferencia de las otras especies en que los acinos glandulares están uniformemente adosados a la pared interna de la cápsula. Se describen nuevos caracteres para la glándula pediosa que mejoran la diagnosis del género Megalobulimus y su evaluación filogenética.

  9. Spatial distribution of Lymnaeidae (Mollusca, Basommatophora), intermediate host of Fasciola hepatica Linnaeus, 1758 (Trematoda, Digenea) in Brazil.

    Science.gov (United States)

    Medeiros, Camilla; Scholte, Ronaldo Guilherme Carvalho; D'ávila, Sthefane; Caldeira, Roberta Lima; Carvalho, Omar Dos Santos

    2014-01-01

    Snails of the family Lymnaeidae act as intermediate hosts in the biological cycle of Fasciola hepatica, which is a biological agent of fasciolosis, a parasitic disease of medical importance for humans and animals. The present work aimed to update and map the spatial distribution of the intermediate host snails of F. hepatica in Brazil. Data on the distribution of lymnaeids species were compiled from the Collection of Medical Malacology (Fiocruz-CMM, CPqRR), Collection of Malacology (MZUSP), "SpeciesLink" (CRIA) network and through systematic surveys in the literature. Our maps of the distribution of lymnaeids show that Pseudosuccinea columella is the most common species and it is widespread in the South and Southeast with few records in the Midwest, North and Northeast regions. The distribution of the Galba viatrix, G. cubensis and G. truncatula showed a few records in the South and Southeast regions, they were not reported for the Midwest, North and Northeast. In addition, in the South region there are a few records for G. viatrix and one occurrence of Lymnaea rupestris. Our findings resulted in the first map of the spatial distribution of Lymnaeidae species in Brazil which might be useful to better understand the fasciolosis distribution and delineate priority areas for control interventions.

  10. Freshwater snails and schistosomiasis mansoni in the State of Rio de Janeiro, Brazil: I - metropolitan mesoregion

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    Thiengo Silvana C

    2001-01-01

    Full Text Available In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954; Biomphalaria glabrata (Say, 1818; Biomphalaria schrammi (Crosse, 1864; Biomphalaria straminea (Dunker, 1848; Biomphalaria tenagophila (Orbigny, 1835; Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835; Drepanotrema cimex (Moricand, 1839; Drepanotrema lucidum (Pfeiffer, 1839; Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962; Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774; Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822; Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.

  11. SPATIAL DISTRIBUTION OF LYMNAEIDAE (MOLLUSCA, BASOMMATOPHORA, INTERMEDIATE HOST OF Fasciola hepatica LINNAEUS, 1758 (TREMATODA, DIGENEA IN BRAZIL

    Directory of Open Access Journals (Sweden)

    Camilla Medeiros

    2014-06-01

    Full Text Available Snails of the family Lymnaeidae act as intermediate hosts in the biological cycle of Fasciola hepatica, which is a biological agent of fasciolosis, a parasitic disease of medical importance for humans and animals. The present work aimed to update and map the spatial distribution of the intermediate host snails of F. hepatica in Brazil. Data on the distribution of lymnaeids species were compiled from the Collection of Medical Malacology (Fiocruz-CMM, CPqRR, Collection of Malacology (MZUSP, “SpeciesLink” (CRIA network and through systematic surveys in the literature. Our maps of the distribution of lymnaeids show that Pseudosuccinea columella is the most common species and it is widespread in the South and Southeast with few records in the Midwest, North and Northeast regions. The distribution of the Galba viatrix, G. cubensis and G. truncatula showed a few records in the South and Southeast regions, they were not reported for the Midwest, North and Northeast. In addition, in the South region there are a few records for G. viatrix and one occurrence of Lymnaea rupestris. Our findings resulted in the first map of the spatial distribution of Lymnaeidae species in Brazil which might be useful to better understand the fasciolosis distribution and delineate priority areas for control interventions.

  12. Toxicity of Chlorophyllin against Lymnaea acuminata at Different Wavelengths of Visible Light

    OpenAIRE

    Chaturvedi, Divya; Singh, Vinay Kumar

    2016-01-01

    Fasciolosis is a water and food-borne disease caused by the liver fluke Fasciola hepatica and Fasciola gigantica. This disease is widespread in different parts of the world. Lymnaeidae and Planorbidae snails are the intermediate hosts of these flukes. Snail population management is a good tool to control fasciolosis because gastropods represent the weakest link in the life-cycle of trematodes. Chlorophyll can be extracted from any green plant. Chlorophyllin was prepared from spinach in 100% e...

  13. Validity reassessment of Trichobilharzia species using Lymnaea stagnalis as the intermediate host.

    Science.gov (United States)

    Rudolfová, J; Hampl, V; Bayssade-Dufour, C; Lockyer, A E; Littlewood, D T J; Horák, P

    2005-01-01

    The systematics within the genus Trichobilharzia is complicated. After the description of the type species Trichobilharzia ocellata, the name was routinely used for nearly all European findings of ocellate furcocercariae. T. ocellata was also described from North America and Japan. However, the identity of T. ocellata remains questionable. Comparison of data from the literature showed differences among various T. ocellata isolates and led us to the conclusion that the North American and the Japanese findings are not identical with European T. ocellata. In addition, the description of T. szidati corresponds with the recently reported European T. ocellata isolates. Sequence analysis of the ITS region confirmed that they are identical.

  14. Fasciola hepatica (Trematode: Fasciolidae en la zona alta de Mérida, Venezuela (Fasciola hepatica (Trematode: Fasciolidae in zone high of Mérida, Venezuela

    Directory of Open Access Journals (Sweden)

    Nieves, E*

    2005-12-01

    Full Text Available Se realizó un estudió sobre la presencia de Fasciola hepática en la finca “El Joque” vía La Azulita, Estado Mérida, Venezuela. Un foco natural de fasciolasis fue verificado por la presencia de formas larvales en los caracoles hospedadores intermediarios y por examen coprológico en los bovinos de la finca. Detectandose la presencia de moluscos en todas las áreas muestreadas de la finca, de los cuales, el 77% resultó ser del Genero Lymnaea (Pulmonata: Lymnaeidae, se determinó una prevalencia de infección de un 42 % en el bebedero, del 43% en el potrero y del 39% en el manantial. Ademas, se detectó un 39% de infección por F. hepática en los bovinos de la finca. La alta prevalencia de F. hepatica en la zona . In the present study was evaluated the presence of Fasciola hepatica in the farm The Joque Merida State, Venezuela. The installation of the natural focus of fascioliasis was verified through of finding the larval forms in the intermediate snail host and coprologics exams in cattle from the farm. The snails were collected in diferents places of the farm, registering the 77% belongs to the Lymnaea genus (Pulmonata:Lymnaeidae intermediator host infected naturally with Fasciola was 42% in the water fill, 43% in the herder and 39% in the source. The results shows that the region presents one prevalence to fascioliasis in cattle of 39%. The very high prevalence of F. hepatica in area studied, suggest that could act as a potential risk to public health.

  15. Occurrence of Fasciola hepatica (Linnaeus, 1758 infection in Brazilian cattle of Minas Gerais, Brazil Ocorrência de Fasciola hepatica Linnaeus, 1758 em rebanhos bovinos do estado de Minas Gerais, Brasil

    Directory of Open Access Journals (Sweden)

    Walter dos Santos Lima

    2009-06-01

    ém foram examinadas, a fim de verificar a presença de hospedeiros intermediários nas propriedades onde foram encontrados bovinos parasitados. Para um total de 16 municípios foi relatada a presença de bovinos infectados por F. hepatica e destes, 13 apresentaram também o molusco Lymnaea columella. Foi possível diagnosticar bovinos infectados em 70% das propriedades visitadas no município de Itajubá. Além disso, no município de Itajubá foi possível detectar a presença de moluscos naturalmente infectados com diferentes estádios larvais de F. hepatica. Os resultados evidenciam a necessidade de medidas de controle para esta parasitose na área estudada, uma vez que foi possível verificar a presença de bovinos e moluscos infectados por F. hepatica, associada a fatores epidemiológicos favoráveis a dispersão do parasito.

  16. Biomphalaria kuhniana (Clessin, 1883, planorbid mollusc from South America Biomphalaria kuhniana (Clessin, 1883, molusco planorbídeo da América do Sul

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1988-03-01

    Full Text Available The validity of Biomphalaria kuhniana (Clessin, 1883 is confirmed through morphological study of specimens from Surinam (type locality and the area of Tucurui (Tocantins river, state of Pará, Brazil in comparison with B. straminea (Dunker, 1848, and throught crossing experiments which revealed complete reproductive isolation between the two species. The full-grown shell of kuhniana is smaller (about 7.5 mm than that of straminea (11 mm to 16.5 mm. Anatomically they differ in the degree of corrugation of the vaginal wall (little developed in kuhniana, conspicuous in straminea, number and shape of prostatic diverticula (kuhniana 4 to 9, shorter and less branched; straminea 9 to 18, longer and more branched,number of muscle layers at the middle of the penis (two in kuhniana, three in straminea, distal segment of the spermiduct usually straight or slightly wavy in kuhniana, more or less curly in straminea. Differences between B. kuhniana and B. intermedia (paraense & Deslandes, 1962 are less marked. The latter has a shell up to about 12 mm in diameter, 7 to 15 prostatic diverticula, two muscle layers at the middle of the penis, and a vaginal wall with a combination of a more or less developed corrugation (or sometimes a mere swelling on the left of the spermathecal duct and a rudimentary pouch on the right of the duct. A Biomphalaria straminea complex is proposed to include that species as well as B. kuhniana and B. intermedia.A validade de Biomphalaria Kuhniana (Clessin, 1883 é confirmada pelo estudo morfológico de espécimes do Suriname (localidade tipo e da área de Tucuruí (rio Tocantins, Estado do Pará, Brasil, em comparação com B. straminea (Dunker, 1848, e por experiências de cruzamento que revelaram completo isolamento reprodutivo entre as duas espécies. A concha adulta de Kuhniana é menor (cerca de 7,5 mm que a de straminea (11 mm a 16.5 mm. As duas espécies distinguem-se anatomicamente pelo grau de enrugamento da parede vaginal (pouco desenvolvido em kuhniana, conspícuo em straminea, pelo número e aspecto dos divertículos prostáticos (em kuhniana 4 a 9, mais curtos e menos ramificados; em straminea 9 a 18, mais longos e mais ramificados, pelo número de camadas musculares na parte média do pênis (duas kuhniana, três em straminea, e pelo percurso do segmento distal do espermiduto, geralmente direto ou ligeiramente ondulado em kuhniana, mais ou menos enroscado em straminea. As diferenças entre B. kuhniana e B. intermedia (Paraense & Deslandes, 1962 são menos acentuadas. Na intermedia a concha atinge cerca de 12 mm de diâmetro, a próstata tem 7 a 15 divertículos, há duas camadas musculares na parte média do pênis e a parede vaginal apresenta um enrugamento mais ou menos desenvolvido (ou às vezes uma simples dilatação à esquerda do canal da espermateca e uma bolsa rudimentar à direita do canal. Em vista da grande semelhança morfológica entre B. straminea, B. kuhniana e B. intermedia, é proposto o agrupamento das três espécies no complexo Biomphalaria straminea.

  17. TÉCNICAS DE SENSORIAMENTO REMOTO APLICADAS À BIOGEOGRAFIA: METODOLOGIA GEOGRÁFICA PARA ESPACIALIZAÇÃO DE MOLUSCOS TERRESTRES

    Directory of Open Access Journals (Sweden)

    Thiago Morato de Carvalho

    2008-06-01

    Full Text Available Este artigo tem como objetivo aplicar algumas técnicasde sensoriamento remoto, como produtos topográficospara interpretação da biogeografia de onze espécies demoluscos terrestres em Lima, Peru. A metodologia consistiuem técnicas de sensoriamento remoto e geoprocessamentopara a elaboração de mapas de localizaçãoe produtos topográficos, como declividade, hipsometria eperfis topográficos para análises geoespacial.

  18. Prospecção de moluscos bivalves no estudo da poluição dos rios Cachoeira e Santana em Ilhéus, Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Denise Sande

    2010-06-01

    Full Text Available A survey about the pollution level of the Cachoeira and Santana Rivers (Ilheus, Bahia, Brazil was performed for a quarter, through the assessment of the microbiological quality of water and seafood (Crassostrea rhizophorae - oyster and Tagelus plebeius - razor clam extracted from these rivers. Traditional indicators of pollution such as total coliforms (Ct and thermtolerant coliforms (CT, and total count of micro-organisms, with isolation and identification of Enterobacteriaceae were determined in rivers samples, which exhibited different levels of faecal pollution. An amount of 68 micro-organisms was isolated, distributed in ten species, among them, Salmonella typhi, Escherichia coli and Shigella sp., warning about the risk of consuming these shellfish in nature, even when there is accordance with the laws established for CT. The bivalve prospection to monitor pollution levels was not effective considering CT detection in oysters and moapens. There was also the highest contamination degree in the Cachoeira River, which is used for water distribution in the region and as livelihood source through extractive activities for the riverside population.

  19. Utilização da berberina na identificação dos mastócitos do molusco Anomalocardia brasiliana

    OpenAIRE

    Cortez, Janice da Silva

    2005-01-01

    A berberina é um alcalóide usado como fluorcromo na identificação de heparina e DNA. Enerbäck, em 1974, descreveu a técnica até hoje empregada deste fluorcromo no estudo dos grânulos ricos em heparina dos mastócitos de vertebrados. Santos et al., em trabalhos anteriores, utilizando abordagens bioquímica e histológica, descreveram a presença de mastócitos no marisco Anomalocardia brasiliana. Baseado nestes estudos, testamos a técnica de fluorescência com berberina para a caracterização adicion...

  20. Los lípidos en la nutrición del abulón azul, molusco con potencial de cultivo

    Directory of Open Access Journals (Sweden)

    Eduardo Durazo Beltrán

    2014-01-01

    Full Text Available Se evaluó el efecto del tipo y nivel de lípidos en el crecimiento y metabolismo de ácidos grasos en abulón azul. La primera parte del estudio se realizó en una granja comercial, donde se analizaron tres tratamientos de alimentación (alimento formulado, macroalga fresca y la combinación de ambos sobre parámetros biológicos y composición de ácidos grasos de organismos juveniles en un periodo de 329 días. Los perfiles de ácidos grasos de los abulones sugieren su capacidad para sintetizar ácidos grasos poliinsaturados n-3 y n-6 de cadena larga a partir de precursores de cadena más corta. En el segundo experimento se evaluó el efecto de la fuente y nivel de ácidos grasos, con trece tratamientos de alimentación y el uso de cuatro aceites comestibles, sobre el crecimiento y composición de ácidos grasos en tejido muscular. No se determinó una relación significativa entre crecimiento y un determinado tipo o nivel de ácido graso, pero se establecieron requerimientos de ácidos grasos n-3 y n-6.

  1. Descripción de un nuevo género y dos especies de moluscos, (Bivalvia), para el Pacífico ecuatoriano

    OpenAIRE

    M. Cruz

    1980-01-01

    Se describe un nuevo género :Eucrassinella y dos nuevas especies: Eucrassinella manabiensis y E. aequatorialis; que pertenecen a la familia Crassatellidae. Se agrega un cuadro comparativo de los géneros ya existentes con el nuevo y otro cuadro de las dos especies recién descritas. De los ejemplares recolectados ocho pertenecen a E. manabiensis y uno a E. aequatorialis. Las dos especies fueron encontradas en la plataforma de la provincia de Manabí y la primera también en los sedimentos recient...

  2. Los lípidos en la nutrición del abulón azul, molusco con potencial de cultivo

    OpenAIRE

    Eduardo Durazo Beltrán

    2014-01-01

    Se evaluó el efecto del tipo y nivel de lípidos en el crecimiento y metabolismo de ácidos grasos en abulón azul. La primera parte del estudio se realizó en una granja comercial, donde se analizaron tres tratamientos de alimentación (alimento formulado, macroalga fresca y la combinación de ambos) sobre parámetros biológicos y composición de ácidos grasos de organismos juveniles en un periodo de 329 días. Los perfiles de ácidos grasos de los abulones sugieren su capacidad para sintetizar ác...

  3. Ecotoxicity of single-wall carbon nanotubes to freshwater snail Lymnaea luteola L.: Impacts on oxidative stress and genotoxicity.

    Science.gov (United States)

    Ali, Daoud; Ahmed, Mukhtar; Alarifi, Saud; Ali, Huma

    2015-01-01

    Mammalian studies have raised concerns about the toxicity of carbon nanotubes, but there is very limited data on ecogenotoxicity to aquatic organisms. The aim of this study was to determine eco-geno toxic effects of single walled carbon nanotubes (SWCNTs) in fresh water snail, Lymnea luteola (L. luteola). A static test system was used to expose L. luteola to a freshwater control, 0.05, 0.15, 0.30, 0.46 mg/L SWCNTs for up to 4 days. SWCNTs changed a significant reduction in glutathione, glutathione-S-transferase, and glutathione peroxidase with in hepatopancreas of L. luteola. Lipid peroxidation (LPO) and catalase showed dose- and time-dependent and statistically significant increase in hepatopancreas during SWCNTs exposure compared with control. However, a significant (p snail L. luteola. The oxidative stress and comet assay can successfully be used as sensitive tools of aquatic pollution biomonitoring.

  4. The participation of NMDA receptors, PKC, and MAPK in the formation of memory following operant conditioning in Lymnaea

    Directory of Open Access Journals (Sweden)

    Rosenegger David

    2010-08-01

    Full Text Available Abstract Background Memory is the ability to store, retain, and later retrieve information that has been learned. Intermediate term memory (ITM that persists for up to 3 h requires new protein synthesis. Long term memory (LTM that persists for at least 24 h requires: DNA transcription, RNA translation, and the trafficking of newly synthesized proteins. It has been shown in a number of different model systems that NMDA receptors, protein kinase C (PKC and mitogen activated protein kinase (MAPK are all involved in the memory formation process. Results Here we show that snails trained in control conditions are capable of forming, depending on the training procedure used, either ITM or LTM. However, blockage of NMDA receptors (MK 801, inhibition of PKC (GF109203X hydrochloride and MAPK activity (UO126 prevent the formation of both ITM and LTM. Conclusions The injection of either U0126 or GF109203X, which inhibit MAPK and PKC activity respectively, 1 hour prior to training results in the inhibition of both ITM and LTM formation. We further found that NMDA receptor activity was necessary in order for both ITM and LTM formation.

  5. Tertiary combination of freeze-dried urine of Indian breeds of cow with plant products against snail Lymnaea acuminata

    National Research Council Canada - National Science Library

    Kumar, Shiv; Singh, D K; Singh, Vinay Kumar

    2012-01-01

    .... In the present study molluscicidal activity of tertiary combination of freeze-dried urine of different Indian breeds of cow Sahiwal, Geer and Tharparkar with Annona squamosa seed powder, Ferula...

  6. Fasciola hepatica: the characteristics of experimental infections in Lymnaea truncatula subjected to miracidia differing in their mammalian origin.

    Science.gov (United States)

    Vignoles, P; Ménard, A; Rondelaud, D; Chauvin, A; Dreyfuss, G

    2001-11-01

    Experimental infections of Lymaea truncatula, using two susceptible snail populations (Berneuil, or Migné, central France) and four isolates of Fasciola hepatica miracidia differing in their mammalian host of origin (cattle, nutrias, rabbits, or sheep), were performed under laboratory conditions to determine whether the host of origin had an effect on the daily production of cercariae. Snails were each subjected to bimiracidial exposures and were then reared under semi-natural conditions (a constant temperature of 20 degrees C and natural photoperiod). Significantly lower values were noted in the rabbit groups for survival rates at day 30 post-exposure, as well as for prevalences of infection, snail growth. duration of shedding period, and the total numbers of cercariae these snails shed. The total number of cercariae shed by both nutria groups was significantly higher than those recorded in the six other infected groups. In the cattle, rabbit, and sheep (Berneuil only) groups, the peaks in the daily distribution of cercariae occurred between day 2 and day 4 after the first shedding, and the number of cercaria-shedding snails decreased with increasing number of shedding waves. In contrast, in the three other groups, the peaks were only observed between days 20 and 45. Snails shedding their cercariae during nine or more waves were numerous in these last groups. No infradian-type rhythm in the daily distribution of cercarial numbers over the shedding period was noted for any snail group. The highest production of F. hepatica cercariae in both nutria groups would be a consequence of a higher success rate of miracidia when they infected an allopatric population of snails. The absence of an infradian-type rhythm in the distribution of daily cercarial numbers in the eight groups suggests that this rhythm, if it occurs, would only be influenced by temperature and thus be limited to periods with optimal conditions for cercarial shedding.

  7. Baseline growth and reproductive parameters in Lymnaea stagnalis for OECD test guideline development: optimization of diets and culturing conditions

    DEFF Research Database (Denmark)

    Holbech, Henrik; Hutchinson, Tom

    guideline. Therefore, we have evaluated other diets based on a review of the published literature and report here the results for different feeds: namely, cabbage leaves, fish flakes, lettuce leaves or sliced sweet potato. For the feeding trial, 5 snails (shell size ca. 2.6 cm) were held in 1 L freshwater...... (snails fed lettuce ad libitum (0.09 mm/snail/day) followed by snails fed fish flake>sweet potato>cabbage leave diets (0.03 mm/snail/day). Similarly, in a 56-d ring-test study with 7 laboratories, the lettuce diet gave...... mean specific growth rates of 0.06-0.09 mm/snail/day. Fecundity in the same test ranged from 519-1424 total embryos per snail. These data will be used towards developing a reference database of growth and reproduction for L. stagnalis and to aid the statistical optimization of the draft OECD test...

  8. Malacofauna límnica da área de influência do lago da usina hidrelétrica de Serra da Mesa, Goiás, Brasil.: I. Estudo qualitativo Freshwater molluscs of the lake of Serra da Mesa dam, Goiás, Brazil.: I. Qualitative study

    Directory of Open Access Journals (Sweden)

    Silvana C. Thiengo

    2005-12-01

    Full Text Available A esquistossomose é uma importante doença endêmica associada a mudanças ambientais causadas por grandes projetos econômicos, tais como a construção de usinas hidrelétricas. A dificuldade de se prever o surgimento de focos de esquistossomose associados com estes empreendimentos e a existência de condições peculiares em cada tipo de projeto requerem estudos em cada uma dessas áreas, de forma a serem implementadas medidas preventivas adequadas. O número crescente de barragens no país é preocupante pois, além de criarem condições propícias ao desenvolvimento dos moluscos vetores, aumentam a população local e o turismo. Nessas áreas, a Organização Mundial de Saúde e a Fundação Nacional de Saúde recomendam ações preventivas contra a instalação de focos de esquistossomose, dentre elas, o monitoramento das populações de moluscos. Neste trabalho são apresentados dados obtidos por nossa equipe na área da Usina Hidrelétrica de Serra da Mesa (UHSM, Goiás, onde levantamentos qualitativos e quantitativos da malacofauna límnica foram realizados de 1997 a 2004, com o principal objetivo de investigar a ocorrência e a distribuição das espécies de interesse médico e veterinário. Vinte e oito espécies, pertencentes a nove diferentes famílias foram encontradas. Além de documentar novas ocorrências no Estado, é também apresentada a distribuição de duas espécies de importância médica, Biomphalaria straminea (Dunker, 1848 e Lymnaea columella Say, 1817, bem como de duas espécies exóticas, Corbicula fluminea (Müller, 1774 e Melanoides tuberculatus (Müller, 1774.Schistosomiasis is an important endemic disease associated with environmental change caused by major economic development projects such as the construction of hydroelectric power facilities (dams and the lakes created by them. The difficulty of predicting emerging outbreaks of schistosomiasis associated with these kinds of projects, and the existence of

  9. Analysis of microsatellites from the transcriptome of downy mildew pathogens and their application for characterization of Pseudoperonospora populations

    Directory of Open Access Journals (Sweden)

    Emma C. Wallace

    2017-05-01

    Full Text Available Downy mildew pathogens affect several economically important crops worldwide but, due to their obligate nature, few genetic resources are available for genomic and population analyses. Draft genomes for emergent downy mildew pathogens such as the oomycete Pseudoperonospora cubensis, causal agent of cucurbit downy mildew, have been published and can be used to perform comparative genomic analysis and develop tools such as microsatellites to characterize pathogen population structure. We used bioinformatics to identify 2,738 microsatellites in the P. cubensis predicted transcriptome and evaluate them for transferability to the hop downy mildew pathogen, Pseudoperonospora humuli, since no draft genome is available for this species. We also compared the microsatellite repertoire of P. cubensis to that of the model organism Hyaloperonospora arabidopsidis, which causes downy mildew in Arabidopsis. Although trends in frequency of motif-type were similar, the percentage of SSRs identified from P. cubensis transcripts differed significantly from H. arabidopsidis. The majority of a subset of microsatellites selected for laboratory validation (92% produced a product in P. cubensis isolates, and 83 microsatellites demonstrated transferability to P. humuli. Eleven microsatellites were found to be polymorphic and consistently amplified in P. cubensis isolates. Analysis of Pseudoperonospora isolates from diverse hosts and locations revealed higher diversity in P. cubensis compared to P. humuli isolates. These microsatellites will be useful in efforts to better understand relationships within Pseudoperonospora species and P. cubensis on a population level.

  10. Moluscos em área de horticultura no município de Porto Alegre, Rio Grande do Sul, Brasil Mollusca in horticultural production area in Porto Alegre county, Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Gisela Bruschi-Figueiró

    2002-12-01

    Full Text Available Horticultural production areas are favorable to development and maintenance of land mollusks populations. To know the mollusk fauna diversity in that kind of production area a research project was conduced in a rural-urban district of Porto Alegre, Rio Grande do Sul, Brazil. The production property studied is located in the Southern zone of the city and has 17 ha of cultivated area. The sampling period was from August/2000 to August/2001, with monthly quantitative collects on the different culture production beds previously selected. Six taxa were registered: Deroceras leave (Müller, 1774 (1.389 specimens = 82,82%, Bradybaena similaris (Férussac, 1821 (195 specimens = 11,7%, Succinea meridionalis d'Orbigny, 1846 (82 specimens = 4,9%, Lamellaxis gracilis (Hutton, 1834 (03 specimens = 0,17%, Bulimulus (Bulimulus vesicalis angustus Weyrauch, 1966 (05 specimens = 0,3% and Megalobulimus abbreviatus (Bequaert, 1948 (02 specimens = 0,11 %, only the last two being natives.

  11. Benzene Synthesis for ''14C Measurements and Evaluation of Uncertainty in Mollusk Shells; Sintesis de Benceno para la Determinacion de C''14 y Evaluacion de su Incertidumbre en Conchas de Moluscos

    Energy Technology Data Exchange (ETDEWEB)

    Romero del Hombrebueno, B.; Simon, M. A.; Larena, P.

    2002-07-01

    This work describes the method and instrumentation used by Environmental Isotopes laboratory of the CIEMAT Analytical Chemistry Laboratory (DIAE) for the synthesis of benzene from carbonates of mollusk shells and the liquid scintillation counting of ''14C for radiocarbon dating in these samples. The usefulness of mollusk shells for ''14 C dating are considered. (Author)

  12. Aspectos ecológicos e distribuição dos moluscos límnicos e seus epibiontes ciliados em quatro municípios da microrregião de Juiz de Fora, Minas Gerais, Brasil

    OpenAIRE

    Lamego, Ana Carolina Rocha

    2015-01-01

    A realização do inquérito malacológico de uma região é importante, pois auxilia o desenvolvimento de pesquisas de caráter mais aplicado; fornece material para estudos taxonômicos como a identificação morfológica e identidade específica; material para coleções científicas e museus; informa a riqueza de espécies – nativas, exóticas e novos registros; monitora a dispersão das espécies que atuam na transmissão de parasitos; entre outros. Além disso, fornece informações sobre a ecologia das espéci...

  13. Estudo sobre a cópula interespecífica entre moluscos planorbídeos Biomphalaria glabrata e B. tenagophila Inter-specific mating between planorbid snails Biomphalaria glabrata and B. tenagophila

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1973-09-01

    Full Text Available Foi estudada a freqüência da cópula interespecífica entre espécimes de Biomphalaria glabrata e B. tenagophila. Os resultados da experiência levaram a conclusão de que há preferência pela cópula intraespecífica, ocorrendo, contudo, cópulas interespecíficas.An experiment on the inter-specific mating of B. glabrata and B. tenagophila snails was related. The results led to conclude that the snails prefer intra-specific mates, even though inter-specific ones occur.

  14. Contaminação por mercúrio em sedimento e em moluscos do Pantanal, Mato Grosso, Brasil Mercury contamination in sediment and in molluscs of Pantanal, Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz M. Vieira

    1995-09-01

    Full Text Available The total level of mercury detected in the sediment and in the tissues of molluscs from the Bento Gomes basin, although low, have shown that the mercury used in the gold mining activities in the Poconé wetlands has contaminated those aquatic habitats in Pantanal. From 69 sediment samples analyzed, 26 % (N = 18 have shown levels ranging from 0.01 to 0.25µg.g-1 of mercury (moist weight. Mercury levels analyzed in 54 samples of mollusc tissues (Ampullaria scalaris Orbigny, 1835; A. canaliculata Lamarck, 1819 and Marisa planogyra Pilsbry, 1933 have shown that 30% (N = 16 were contaminated with levels ranging from 0.02 to 1.16µg.g-1 moist weight. This study shows that the mercury used in digs for gold mining and released into the environment has reached the habitats of Pantanal spread from the sediment into the molluscs living in the region.

  15. Caracterização físico-química e microestrutural de conchas de moluscos bivalves provenientes de cultivos da região litorânea da ilha de Santa Catarina

    OpenAIRE

    Silva, Denyo; Debacher,Nito Angelo; Castilhos Junior,Armando Borges de; Rohers,Fabio

    2010-01-01

    Samples of shells of oysters and mussels from sea farm around the Santa Catarina Island in south Brazil were collected and analyzed by DRX, FRX, SEM, CHN-S, FTIR, TG, AAS/Flame and AAS /GF. The results showed that the crystalline structure of mussel's shells is mainly formed by aragonite and the oyster's shells by calcite. The calcium percentage in both shells species was in the range of 33 to 35% and also 850 and 1200 mg/kg of strontium was detected in the shells of oysters and mussels, resp...

  16. Las ofrendas de concha de moluscos de la Pirámide de las Serpientes Emplumadas, Xochicalco, Morelos The shell offerings inside the Pyramid of the Plumed Serpents in Xochicalco, Morelos

    Directory of Open Access Journals (Sweden)

    Emiliano Ricardo Melgar-Tísoc

    2007-10-01

    Full Text Available El propósito del presente trabajo fue evaluar los análisis llevados a cabo en los materiales de concha procedentes de la Pirámide de las Serpientes Emplumadas de Xochicalco, Morelos. Se identificaron 12 especies, 9 del Pacífico y 3 del Caribe. La tipología y las huellas de manufactura analizadas con microscopio electrónico de barrido (MEB mostraron 2 patrones: una heterogeneidad y dispersión de las áreas de producción en la primera etapa, frente a la estandarización y concentración de las áreas de producción, quizás un taller bajo control de la élite, de la última etapa.The aim of this study was to analyze the shell assemblage of the Pyramid of the Plumed Serpents in Xochicalco, Morelos. Twelve species were identified, 9 from the Panamic-Pacific province and the remaining 3 from the Caribbean Sea. Using Scanning Electron Microscopy (SEM, the typology and traces of working showed two patterns of manufacture: 1 variability and wide dispersal from the areas of production and, contrasting with this, 2 standardization of manufacture and centralization in those areas where, perhaps in latter stages, the shell workshop was under the control of elite members of the community.

  17. Ocorrência de moluscos límnicos e crustáceo em macroaglomerados do mexilhão dourado, Limnoperna fortunei (Dunker, 1857 sobre sarandi no lago Guaíba (RS, Brasil

    Directory of Open Access Journals (Sweden)

    Maria Cristina Dreher Mansur

    2008-01-01

    amostras; Potamolithus jacuhyensis Pilsbry, 1899 (35,71%, como espécie acessória e o crustáceo Hyalella curvispina Shoemaker, 1942 (26%, como espécie acessória. Os demais táxons foram acidentais (<25%: Ampullariidae (indivíduos jovens; Heleobia davisi (Silva & Thomé, 1985; Chilina parva (Martens, 1868 e Corbicula fluminea (Müller, 1774. As relações interespecíficas destes táxons são até o momento pouco conhecidas.

  18. Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

    OpenAIRE

    José Ángel Bautista Cotorruelo; Carolina Gutiérrez Molina; María José Martínez Cánovas; María Elisa Gómez Campoy; Juana Díaz Rodríguez; María José Herrera Díaz; Juan Francisco Sánchez Pérez

    2008-01-01

    The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de ...

  19. Biogeography and biodiversity of gastropod molluscs from the eastern Brazilian continental shelf and slope Biogeografía y biodiversidad de moluscos gastrópodos de la plataforma y talud continental brasileño

    Directory of Open Access Journals (Sweden)

    Gabriela Benkendorfer

    2009-01-01

    Full Text Available Biogeographic distributional patterns of gastropods are proposed based on the species' geo-graphic and bathymetric distribution. Samples were collected along the Brazilian continental margin between 18° S and 23° S, at 37 stations with depths from 20 m to 1,330 m. The analysis of the biogeographic distribution patterns confirmed the existence of a transitional zone from tropical to subtropical waters in the area of both the continental shelf and slope, suggesting a relationship with water mass circulation. We observed a high species turnover rate between the shelf and slope. The analysis of gastropod species distribution revealed a similar pattern on the shelf and slope and a large difference between shallow and deep-water faunas.Los patrones de distribución biogeográfica de gastrópodos fueron propuestos basados en la distribución geográfica y batimétrica de las especies. Los muestreos fueron realizados en el margen continental brasileño entre 18°S y 23°S, en 37 estaciones de 20 m a 1.330 m de profundidad. El análisis de los patrones de distribución biogeográfica confirmó la existencia de una zona de transición de aguas tropicales a aguas subtropicales, que se encuentra en la zona de la plataforma continental y también en la zona del talud continental, esto puede sugerir una relación con la circulación de las masas de agua. Se observó una elevada tasa de turnover de las especies entre la plataforma y el talud continental. El análisis de las especies de gastrópodos reveló un patrón similar tanto en la plataforma como en el talud y una gran diferencia entre las faunas de las aguas someras y profundas.

  20. EFECTO INMUNOESTIMULADOR Y TECNOLOGIA DE PRODUCCION DE OLIGOSACARIDOS (BETA (1,3-1,6) GLUCANOS) EXTRAIDOS DE ALGAS PARDAS CULTIVADAS Y SU EVALUACION EN CULTIVOS DE PECES Y MOLUSCOS

    OpenAIRE

    2012-01-01

    La acuicultura nacional ha sufrido grandes impactos sanitarios debido a los brotes de enfermedades en cultivos de salmones, lo que genera grandes perdidas económicas, actualmente, uno de los principales focos de la atención en la industria está en la prevención de estas enfermedades, ya sea a través de la utilización de vacunas, prebióticos o inmunoestimulantes. En la búsqueda de nuevos métodos de control biológicos, el proyecto consistió en desarrollar un nuevo producto inmunoestimulan...

  1. Crystal Structure of Lymnaea stagnalis AChBP Complexed with the Potent nAChR Antagonist DHßE Suggests a Unique Mode of Antagonism

    DEFF Research Database (Denmark)

    Shahsavar, Azadeh; Kastrup, Jette S; Nielsen, Elsebet Ø.;

    2012-01-01

    Nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated ion channels that belong to the Cys-loop receptor superfamily. These receptors are allosteric proteins that exist in different conformational states, including resting (closed), activated (open), and desensitized (closed) states...

  2. Accumulation and detoxication responses of the gastropod Lymnaea stagnalis to single and combined exposures to natural (cyanobacteria) and anthropogenic (the herbicide RoundUp® Flash) stressors

    DEFF Research Database (Denmark)

    Lance, Emilie; Desprat, J.; Holbech, B. F.

    2016-01-01

    , and ii) activities of anti-oxidant (catalase CAT) and biotransformation (glutathione-S-transferase GST) enzymes. During the intoxication, the cyanobacterial exposure induced an early increase of CAT activity, independently of the MC content, probably related to the production of secondary cyanobacterial...... previously exposed to MC-producing cyanobacteria with or without RoundUp® Flash than in other conditions, probably related to the oxidative stress caused by accumulated MCs remaining in tissues. © 2016 Elsevier B.V....... to MC-producing cyanobacteria with RoundUp®, suggesting interacting effects of MCs on biotransformation processes. The potent inhibition of detoxication systems by MCs and RoundUp® Flash was reversible during the depuration, during which CAT and GST activities were significantly higher in snails...

  3. Ocorrência de Achatina fulica no Vale do Paraíba, Estado do Rio de Janeiro, Brasil

    Directory of Open Access Journals (Sweden)

    Vasconcellos Maurício Carvalho de

    2001-01-01

    Full Text Available Registrou-se no município de Resende, Estado do Rio de Janeiro, Brasil, a primeira ocorrência do molusco Achatina fulica hospedeiro intermediário de Angiostrongylus cantonensis, causador da angiostrongilíase meningoencefálica. Em cinco bairros visitados, foram encontrados moluscos vivendo livremente, e nenhum dos animais coletados apresentava a forma larvar do parasito. A presença de A. fulica pode estar relacionada à comercialização desse molusco como alimento, e representa possibilidade de instalação dessa zoonose na região.

  4. Estudo dos dados obtidos de uma população de Biomphalaria glabrata de Belo Horizonte infectada por schistosoma mansoni da mesma cidade, e de uma população de B. tenagophila de Campinas. infectada por S. mansoni de São José dos Campos

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1969-01-01

    Full Text Available O autor estuda os dados obtidos pela infecção de moluscos de Campinas e de Belo Horizonte por miracídios de S. mansoni. Chega à conclusão de que a população de Belo Horizonte mostrou-se mais susceptível à infecção pelo helminto do que a população de moluscos Campinas.

  5. AcEST: BP921322 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Q592S0 Definition tr|Q592S0|Q592S0_LYMST Putative uncharacterized protein (Fragment) OS=Lymnaea stagnalis Al...3 9.5 >tr|Q592S0|Q592S0_LYMST Putative uncharacterized protein (Fragment) OS=Lymnaea stagnalis PE=2 SV=1 Len

  6. AcEST: BP916705 [AcEST

    Lifescience Database Archive (English)

    Full Text Available S=Methano... 31 3.8 sp|Q6QUW1|RGP51_LYMST Retrograde protein of 51 kDa OS=Lymnaea st... 30 5.0 sp|Q73I07|DCD...EDDFKEIENIIQKLCKKKCIIDKENKLLRVDKDIVILPEN 321 >sp|Q6QUW1|RGP51_LYMST Retrograde protein of 51 kDa OS=Lymnaea

  7. AcEST: BP913084 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ETJA Uncharacterized protein MJECL32 OS=Methano... 31 5.2 sp|Q6QUW1|RGP51_LYMST Retrograde protein of 51 kDa OS=Lymnaea... Sbjct: 282 EDDFKEIENIIQKLCKKKCIIDKENKLLRVDKDIVILPEN 321 >sp|Q6QUW1|RGP51_LYMST Retrograde protein of 51 kDa OS=Lymnaea

  8. AcEST: DK963325 [AcEST

    Lifescience Database Archive (English)

    Full Text Available G-protein coupled receptor GRL101 OS=Lymnaea stagnalis Align length 21 Score (bit) 30.8 E-value 4.3 Report ...GR101_LYMST G-protein coupled receptor GRL101 OS=Lymna... 31 4.3 >sp|P46023|GR101_LYMST G-protein coupled receptor GRL101 OS=Lymnaea

  9. Asociación de floraciones de algas nocivas y Vibrio spp. en áreas de pesca y acuicultura de bivalvos de moluscos en las bahías de Sechura y Pisco, Perú/Harmful algal blooms and Vibrio spp. association in fishing and marine farming areas of mollusk bivalves in Sechura and Pisco bays, Peru

    National Research Council Canada - National Science Library

    Rita Orozco; Yessica Quispe; Alberto Lorenzo; María Luz Zamudio

    2017-01-01

    The temperatures in this area ranged from 21.8 to 25.3 °C. In Pisco, the harmful algal bloom-forming Akashiwo sanguinea, Messodinium rubrum, and Prorocentrum minimum and the dinoflagellate Cochlodinium polikrykoides were most prevalent...

  10. Threatened Neotropical mollusks: analysis of shape differences in three endemic snails from High Paraná River by geometric morphometrics Moluscos neotropicales amenazados: análisis de diferencias de forma en tres caracoles endémicos del río Alto Paraná mediante morfometría geométrica

    Directory of Open Access Journals (Sweden)

    Roberto E. Vogler

    2012-12-01

    Full Text Available Variation in shape among a living and 2 extinct aquatic snails of the genus Aylacostoma, using a geometric morphometric method of thin plate splines and multivariate analysis was investigated. The analysis was performed to evaluate the diagnostic capability of this method and to explore shell shape differences, due to the lack of other data, in an attempt to answer why only 1 of the species persisted in the wild. Sixteen landmarks in a bi-dimensional space for 32 shells of type, paratype and reference specimens deposited in museums of Argentina were defined. Analysis was successful in assigning individual specimens to particular species. Statistically significant differences in last whorl, aperture, and spire were found for the first 4 non-uniform components explaining an 85% of local variation observed. Differences could be related to a differential use of habitat and/or to the degree of exposure to water current. More globose shell found in the extinct species could be associated to habitats and substrata with the highest water currents, whereas the more stylized shell in the third species could be related to a preference for more protected habitats, like those where it presently occurs.La variación de forma entre una especie viviente y dos extintas de caracoles acuáticos del género Aylacostoma, fue investigada mediante el método de morfometría geométrica de "thin plate splines" y análisis multivariado. El análisis se realizó para evaluar la capacidad diagnóstica del método y explorar las diferencias de forma de conchilla, debido a la falta de otros datos, en un intento por responder por qué sólo una de las especies persistió en la naturaleza. Dieciséis "landmarks" fueron definidos en un espacio bi-dimensional para 32 conchillas de ejemplares tipo, paratipo y de referencia depositados en museos de Argentina. El análisis fue exitoso en la asignación de los individuos a especies particulares. Se encontraron diferencias significativas en el último anfracto, apertura y espira respecto de los 4 primeros componentes no uniformes, que explicaron el 85% de la variación observada. Estas diferencias podrían vincularse a un uso diferencial del hábitat y/o al grado de exposición a la corriente. La conchilla más globosa en las especies extintas pudo estar asociada a hábitats y sustratos con mayores corrientes, mientras que la conchilla más estilizada en la tercera especie podría estar relacionada con la preferencia por hábitats más protegidos, como los que actualmente habita.

  11. Levantamento preliminar de moluscos em praias arenosas e areno-lodosas de Piúma, estado do Espírito Santo, Brasil Preliminary study of the mollusks in sandy and sandy-nuddy beachs of Piúma, Espírito Santo State, Brazil

    Directory of Open Access Journals (Sweden)

    Gilson Alexandre de Castro

    1989-01-01

    Full Text Available The present work is a preliminary contribution to the knowledge of the fauna, with regard to the aspect of mullusks, on the coast located in the city of Piúma (40º45' lat. L and 20º50' long. W Espírito Santo State, aiming a better comprehension of the distribution and ecology of mollusks in the South Atlantic. Collections were made in planned sporadic periods (May/29 to 31 of 1984; May/04-05 and September/13-16 of 1985; March/26-28; October/30-31 and November/01-02 of 1986, in the intertidal zones in the area, in each chosen region and in presence of an 0.0 tide. The material identified by comparative analysis of the morphologic variability presented a total of 41 generic taxa (52.56% and 44 specific taxa (52.38% of the class Gastropoda, 36 generic taxa (46.15% and 39 specific taxa (46.43% of the class Bivalvia and 1 generic taxa (1,28% and 1 specific taxa (1.19% of the class Scaphopoda.

  12. Caracterização físico-química e microestrutural de conchas de moluscos bivalves provenientes de cultivos da região litorânea da ilha de Santa Catarina Physical chemistry and micro structural characterization of shells of bivalve mollusks from sea farmer around the Santa Catarina island

    Directory of Open Access Journals (Sweden)

    Denyo Silva

    2010-01-01

    Full Text Available Samples of shells of oysters and mussels from sea farm around the Santa Catarina Island in south Brazil were collected and analyzed by DRX, FRX, SEM, CHN-S, FTIR, TG, AAS/Flame and AAS /GF. The results showed that the crystalline structure of mussel's shells is mainly formed by aragonite and the oyster's shells by calcite. The calcium percentage in both shells species was in the range of 33 to 35% and also 850 and 1200 mg/kg of strontium was detected in the shells of oysters and mussels, respectively. The content of organic matter was larger in the mussel's shells and the thermal degradation of both shells species occurred by three events at different temperatures from 250 to 830 ºC.

  13. Caracterização físico-química e microestrutural de conchas de moluscos bivalves provenientes de cultivos da região litorânea da ilha de Santa Catarina Physical chemistry and micro structural characterization of shells of bivalve mollusks from sea farmer around the Santa Catarina island

    OpenAIRE

    Denyo Silva; Nito Angelo Debacher; Armando Borges de Castilhos Junior; Fabio Rohers

    2010-01-01

    Samples of shells of oysters and mussels from sea farm around the Santa Catarina Island in south Brazil were collected and analyzed by DRX, FRX, SEM, CHN-S, FTIR, TG, AAS/Flame and AAS /GF. The results showed that the crystalline structure of mussel's shells is mainly formed by aragonite and the oyster's shells by calcite. The calcium percentage in both shells species was in the range of 33 to 35% and also 850 and 1200 mg/kg of strontium was detected in the shells of oysters and mussels, resp...

  14. Padrões distributivos e zoogeografia dos moluscos da plataforma continental brasileira: Parte III. Comissão Oceanográfica Espiríto Santo I Distribution patterns and zoogeography of the mollusks from the Brazilian continental shelf: Part III. Oceanographic Expedition Espirito Santo I

    Directory of Open Access Journals (Sweden)

    Ricardo Silva Absalão

    1989-01-01

    Full Text Available One hundred senventy-five species of marine mollusks have been identified in the Expedition Espírito Santo I. Standing out the species Margarites olivaceus (Brown, 1827; Cyclostremiscus caraboboensis Weishord, 1962; Balcis gibba Folin, 1867; Triphora compsa (Dall, 1927; Henrya af. goldmani Bartsh, 1947 and Limaea subovata Jeffreys, 1876 as they have not been previously assigned to Brazil. The analysis of the geographical distribution patterns points out the dominance of the species with thermophiles affinities. This situation evidences the importance of the Brazilian Current in the maintanance of the biogeographical structure of the studied region. However, it is the analysis of the cryophiles species that shows the Cabo Frio region as an ecological filter quite more permeable to the species with thermophile affinities than to the cryophiles ones. The existence of this barrier and the endemism rate (4.27% characterize the region that extends from the south of Cabo Frio as a transition between the two patterns cited above. Therefore they do not corroborate in malacological parameters the proposition made by Palacio (1982 for the individualization of the Paulista Province.

  15. Aproximación a los riesgos derivados de la presencia de residuos mineros en saladares del entorno del Mar Menor: dinámica de metales pesados y arsénico y su acumulación en plantas y moluscos

    OpenAIRE

    María Cervantes, Antonio

    2011-01-01

    [ESP] El Mar Menor, localizado en el sureste de España, es una de las lagunas costeras más grandes de Europa y del Mediterráneo. A pesar de las diversas figuras de protección medioambiental que obstenta, esta laguna y sus humedales asociados se encuentran afectados por diversas actividades antrópicas, entre las que destacan la presencia de residuos mineros procedentes de la antigua zona minera de Cartagena-La Unión, transportados y depositados durante los periodos de lluvias torrenci...

  16. Lymnaea cousini, huésped de Fasciola hepatica en el trópico alto andino de Colombia, y sus nuevos haplotipos, confirmados con el marcador mitocondrial del gen de la citocromo oxidasa I

    Directory of Open Access Journals (Sweden)

    Nelson Uribe

    2014-12-01

    Conclusión. Mediante el marcador mitocondrial del COI, se confirmó que los especímenes pertenecían a la especie L. cousini. Con el hallazgo se duplicó el número de haplotipos conocidos de la especie en Colombia y se amplió su distribución geográfica al suroeste y nordeste de la región altoandina colombiana.

  17. Musgos de Costa Rica : nuevos registros

    OpenAIRE

    Arrocha, Clotilde

    1992-01-01

    Fifteen species of mosses are reported as new to Costa Rica, five of those are new to Central America. These are: Paraleucobryum albicans (Schwaegr.) Loeske, Philonotis elongata (Dism.) Crum & Steere, Leskeodon cubensis (Mitt.) Thér., Hookeriopsis dimorpha (C.M.) Broth. and Isopterygium machrisianum (Crum) Irel.

  18. A study of the correlation between molluscum contagiosum and atopic dermatitis in children

    OpenAIRE

    Maria Bandeira de Melo Paiva Seize; Mayra Ianhez; Silmara da Costa Pereira Cestari

    2011-01-01

    FUNDAMENTOS: É bastante divulgado, sem a fundamentação científica necessária, que a infecção por molusco contagioso tende a ser mais frequente e de maior intensidade nos pacientes acometidos por dermatite atópica. Tal fato motivou a realização deste trabalho. OBJETIVOS: Avaliar a prevalência de associação de dermatite atópica e molusco contagioso; avaliar se, nos pacientes com dermatite atópica, a infecção por molusco contagioso é mais recorrente e/ou disseminada e se a ocorrência de eczema p...

  19. Status report on Fish Springs pond snail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides a life history of the pond snail (Lymnaea Hinkleyia pilsbryi) at Fish Springs National Wildlife Refuge. The following information is included;...

  20. Applications of inter simple sequence repeat (ISSR) rDNA in ...

    African Journals Online (AJOL)

    Applications of inter simple sequence repeat (ISSR) rDNA in detecting ... and phylogenetic relationships between Lymnaea natalensis collected from Giza, ... in water samples of all tested governorates with different significant differences.

  1. Suscetibilidade de biomphalaria glabrata, B. straminea e B. tenagophila a diferentes cepas de schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Luiz Candido de Souza Dias

    1987-08-01

    Full Text Available Em condições experimentais foi estudada a suscetibilidade de Biomphalaria glabrata, B. straminea e B. tenagophila a quatro linhagens humanas (MAP, PTH, UPH, e OuH e duas de roedores silvestres (PTR e VPR do Schistosoma mansoni. Grupos de 50 moluscos foram expostos individualmente a 10 miracídios e observados durante 70 dias. Avaliou-se a suscetibilidade dos moluscos ao parasito por meio da % de animais com esporocistos, % de moluscos que eliminavam cercárias e mortalidade conjunta dos animais expostos e infectados. Exemplares de B. glabrata mineira infectaram-se com cepa simpátrica (MAP e com 5 alopátricas do Estado de São Paulo (PTH, VPH, OuH, PTR e VPR. B. glabrata paulista mostrou altas taxas de infecção com as cepas MAP, VPR e OuH do trematódeo. Quatro % dos exemplares B. straminea de São Paulo eliminavam cercárias de cepas simpátricas; com cepa mineira apenas 4% apresentaram esporocistos na vigência de 20 miracídios por molusco; as menores taxas de mortalidade foram registradas com essa espécie de molusco, não sendo maior do que 20%. B. tenagophila paulista foi suscetível apenas às linhagens simpáticas sendo 6% a maior taxa de moluscos que eliminaram cercárias. Os resultados indicam que os movimentos populacionais humanos dentro do território paulista e para fora dele são importantes na disseminação da esquistossomose mansônica.

  2. The geographical distribution and habitats of three liver fluke intermediate hosts in South - Africa and the health implications involved

    OpenAIRE

    K. N. de Kock; C. T. Wolmarans

    2008-01-01

    Account is given of the distribution and habitats of the three Lymnaea species currently on recordin the National Freshwater Snail Collection (NFSC) of South Africa. A total number of 616, 353and 202 loci (1/16th square degrees) was respectively recorded for Lymnaea natalensis, L. columellaand L. truncatula. The number of loci in which the collection sites of each species was located, wasdistributed in intervals of mean annual air temperature and rainfall, as well as intervals of meanaltitude...

  3. Quantification of {sup 232}Th, {sup 234}U, {sup 235}U and {sup 238}U in river mollusks by magnetic sector mass spectrometry with inductively coupled plasma source (Icp-SFMS); Cuantificacion de {sup 232}Th, {sup 234}U, {sup 235}U y {sup 238}U en moluscos de rios por espectrometria de masas de sector magnetico con fuente de plasma acoplado inductivamente (ICP-SFMS)

    Energy Technology Data Exchange (ETDEWEB)

    Arevalo R, D. L.; Hernandez M, H.; Romero G, E. T.; Lara A, N. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Alfaro de la T, M. C., E-mail: arevalo0591@hotmail.com [Universidad Autonoma de San Luis Potosi, Dr. Salvador Nava s/n, Zona Universitaria, 78290 San Luis Potosi, SLP (Mexico)

    2016-09-15

    The present work deals with the methodology established for the quantification of {sup 232}Th, {sup 234}U, {sup 238}U and {sup 235}U in the shell of gastropod mollusks collected in the rivers Valles, Coy and Axtla of San Luis Potosi, Mexico, which belong to the Panuco River basin; these rivers have as main source of pollution the discharge of municipal sewage, waste from small industries, agricultural and cattle residues and from natural sources. Conventional methods for measuring radio-nuclides are confronted with certain conditions related to the requirement in measurement, basically in the characterization that is related to the concepts of precision and accuracy. The analysis of the gastropod mollusk shell was performed by the Icp-SFMS technique; the main advantages of this technique lie in the isotope quantification capacity, the high precision and the low limits of detection, in this study are very important because these elements are in concentrations between ppb and ppt. This technique allowed the analysis of the samples having a complex matrix by the presence CaCO{sub 3} minimizing the interferences thanks to the ionization efficiency of the Ar plasma. For the species Pachychilus monachus were found concentrations of {sup 232}Th of 0.16-5.37 μg/g and of total U of 0.101-4.081 μg/g being this species where the highest values of total U were found. For Thiara (melanoids) tuberculata the lowest values were found among the different species ({sup 232}Th 0.61-3.61 μg/g and total U 0.006-0.042 μg/g), for Pachychilus suturalis, values of {sup 232}Th of 0.58-6.4 μg/g and for Pachychilus sp. were found between 0.26-7.62 μg/g and for total U values between 0.28-3.33 μg/g. The method offers several advantages: speed, good precision, low values of quantification limits and high sensitivity in the measurement of radio-nuclides and heavy metals. (Author)

  4. Distribución de especies de la clase mollusca en el corregimiento de Veracruz, Distrito de Arraiján, Provincia de Panamá

    OpenAIRE

    Avilés E., Miguel C.; Córdoba G., Darío E.

    2008-01-01

    En este trabajo se presenta la distribución de las especies de moluscos colectadas en el corregimiento de Veracruz, distrito de Arraiján, Panamá. Las muestras están depositadas en la Colección Nacional de Referencia de Moluscos del Museo de Malacología de la Universidad de Panamá (MUMAUP). Esta localidad se caracteriza por ser un área fangosa, arenosa y pedregosa, con poca vegetación. Se elaboró un mapa de ocurrencia para las especies, en dos sitios: playa Veracruz e isla Venado, distinguiénd...

  5. Experiencias en sistema controlado para la obtención de semillas de concha de abanico Argopecten purpuratus (Lamarck, 1819) . Ilo, Moquegua

    OpenAIRE

    2011-01-01

    IMARPE Ilo obtuvo financiamiento del Gobierno Regional de Moquegua en base al proyecto "Mejoramiento de infraestructura e implementació n de laboratorio de investigació n de molusc"os, para construir un laboratorio experimental con el objetivo de desarrollar técnicas de reproducción artificial de moluscos nativos de la Región, para la obtención de semillas principalmente de macha Mesodesma donacium, chanque Concholepas concholepas y pulpo Octopus mimus. Este informe contiene el resultado ...

  6. Molluscum contagiosum on tattoo

    OpenAIRE

    Luciana Molina; Ricardo Romiti

    2011-01-01

    Molusco contagioso é uma dermatovirose causada por poxvírus e caracterizada por erupção benigna e autolimitada de uma ou múltiplas pápulas esféricas e brilhantes. A transmissão habitualmente ocorre por contato direto com indivíduos infectados. Relata-se caso de doente masculino, 22 anos, com história de surgimento de numerosas pápulas umbilicadas localizadas estritamente sobre a região de uma tatuagem. Exame histopatológico de uma das pápulas confirmou a hipótese clínica de molusco contagioso...

  7. Evaluacion comparativa de dos tipos de muestreo en chucheca (Grandiarca grandis) y piangua (Anadara tuberculosa), en el Golfo de Nicoya, Costa Rica (ING)

    OpenAIRE

    Juan Bolaños Montero

    2016-01-01

    Se realizó un estudio comparativo para probar la bondad estadística de dos métodos de muestreo de moluscos en el ecosistema de manglar. El muestreo por estratos resultó ser mejor que el muestreo irrestricto al azar.

  8. Evaluacion comparativa de dos tipos de muestreo en chucheca (Grandiarca grandis y piangua (Anadara tuberculosa, en el Golfo de Nicoya, Costa Rica (ING

    Directory of Open Access Journals (Sweden)

    Juan Bolaños Montero

    2016-03-01

    Full Text Available Se realizó un estudio comparativo para probar la bondad estadística de dos métodos de muestreo de moluscos en el ecosistema de manglar. El muestreo por estratos resultó ser mejor que el muestreo irrestricto al azar.

  9. Registro de ocorrência de vetores da esquistossomose mansônica em açude do Sertão de Pernambuco

    National Research Council Canada - National Science Library

    Pierre Gazin; Constança Simões Barbosa; Marc Bouvy; Pierre Audry

    2000-01-01

    ... a ocorrência de Biomphalaria straminea em açude da região, constatando que suas águas têm características físico-químicas favoráveis à proliferação destes moluscos. Chama a atenção para a possibilidade...

  10. Potential use of RAPD markers in characteristics of cucumber (Cucumis sativus L. haploids and double-haploids

    Directory of Open Access Journals (Sweden)

    Katarzyna Niemirowicz-Szczytt

    2011-04-01

    Full Text Available A study was designed to obtain hapolid and double haploid (DH plants from cucumber cultivars tolerant to Pseudoperonospora cubensis. The main goal was to identify RAPD molecular markers associated with downy mildew resistance. On average, 20% of embryos generated in two experiments, were converted to haploid plants. RAPD markers that differentiated susceptible and resistant H and DH plants were identified. Somaclonal variation in DH lines was seldom detected.

  11. Oxygen uptake during mineralization of humic substances from Infernão Lagoon (São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    M. B. Cunha-Santino

    Full Text Available Assays were carried out to evaluate the dissolved oxygen uptake resulting from mineralization of humic substances (fulvic acid (FA and humic acid (HA from different sources: sediment, dissolved organic matter (DOM of 120-day decomposed aquatic macrophyte (Scirpus cubensis and Cabomba piauhyensis, and lagoon DOM. The experiments were also aimed at estimating the oxygen uptake coefficient of the mineralization. About 20-30 mg of substrate were added to 1.1 liters of water from Infernão Lagoon (21º33' to 21º37'S; 47º45' to 47º51'W. The solutions were aerated and the dissolved oxygen (DO was monitored during 40 days. Dissolved organic carbon (DOC and particulate organic carbon (POC were estimated after 80 days of the experiment. Anaerobic processes were avoided by aerating the solutions. The results were fitted to a first-order kinetics model, from which the uptake of oxygen parameters was obtained. Oxygen consumption (OC ranged from 4.24 mg L-1 (HA - S. cubensis to 33.76 mg L-1 (FA - sediment. The highest deoxygenation coefficient (kD was observed during mineralization of FA - DOM (0.299 day-1, followed in decreasing order by FA - S. cubensis, HA - sediment, HA - S. cubensis, FA - sediment, and FA - C. piauhyensis (0.282; 0.255; 0.178; 0.130, and 0.123 day-1, respectively. The carbon analyses indicated that the FA and HA samples at the end of the experiment presented a decay that varied from 15.23% to 42.35% and that the FA and HA conversions into POC were relatively low (from 0.76% to 3.94%.

  12. Potassium Bicarbonate as a Potential Sulphur Substitute in Protected Organic Cropping

    OpenAIRE

    Koller, Martin

    2011-01-01

    Powdery mildew attacks several important crops in greenhouses (e.g. tomatoes, cucumbers). Compared to other airborne pathogens, such as downy mildews (e.g. Pseudoperonospora cubensis or Phytophthora infestans) or Botrytis, the damage is often not very severe. However, an effective control of powdery mildew with organic fungicides gives the possibility to optimize climate conditions to also prevent downy mildews and gray mold. Sulphur, a well established fungicide, is rated as slightly to very...

  13. Cloning and Expression Analysis of Downy Mildew Resistance-Related cDNA Sequences in Melon

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Melon downy mildew caused by Pseudoperonospora cubensis leads to significant losses in melon yields worldwide.Reverse-transcription Polymerase Chain Reaction (RT-PCR) was performed using cDNAs as templates from melonHuangdanzi induced with fungus Pseudoperonospora cubensis, and degenerate primers designed based on the conserved amino acid sequences of known plant disease-resistance genes. A polymorphic cDNA fragment which we named mp-19was cloned and sequenced. The Open Reading Frame (ORF) of this product comprised of 510 base pairs which encodes DNA or RNA-binding protein with 170 amino acids. The putative amino acid sequence of mp-19 appeared highly homologous with those of NBS-type resistant-genes isolated from other plants. Southern blot indicated that the melon genome contained more than 3 copies of mp-19. The obvious expression differences detected by semi-quantitative RTPCR could be observed between resistant-line Huangdanzi and susceptible-line Jiashi after Pseudoperonospora cubensis infection, which implied that mp-19 gene may be related to the resistance of downy mildew in melon.

  14. Population dynamics of intermediate snail hosts of Fasciola hepatica and some environmental factors in San Juan y Martinez municipality, Cuba

    Directory of Open Access Journals (Sweden)

    Roberto Cañete

    2004-05-01

    Full Text Available The variation of abundances of intermediate snail hosts of Fasciola hepatica in Cuba (Fossaria cubensis and Pseudosuccinea columella was studied during one year under natural conditions at five sampling sites in San Juan y Martinez municipality, Pinar del Rio province, Cuba. The effect of some environmental variables on the lymnaeid abundances was also studied. A canonical correspondence analysis showed that both species do not generally occur together in the same habitat and that most factors affect them in an opposite fashion, although both of them correlate positively through time to the diversity of the habitats. F. cubensis prefers the sites that are in or closer to the city whereas P. columella is more abundant in rural sites. Lymnaeid abundances are mainly affected by nitrite and nitrate concentrations as well as by the abundance of the thiarid Tarebia granifera. F. cubensis is more abundant in polluted habitats with low densities (or absence of T. granifera whereas P. columella prefers cleaner habitats and can coexist with the thiarid, even at its higher densities. The implications of divergent preferences of the two lymnaeids for the control of fasciolosis are discussed.

  15. Identification and characterization of potential NBS-encoding resistance genes and induction kinetics of a putative candidate gene associated with downy mildew resistance in Cucumis

    Directory of Open Access Journals (Sweden)

    Wan Hongjian

    2010-08-01

    Full Text Available Abstract Background Due to the variation and mutation of the races of Pseudoperonospora cubensis, downy mildew has in recent years become the most devastating leaf disease of cucumber worldwide. Novel resistance to downy mildew has been identified in the wild Cucumis species, C. hystrix Chakr. After the successful hybridization between C. hystrix and cultivated cucumber (C. sativus L., an introgression line (IL5211S was identified as highly resistant to downy mildew. Nucleotide-binding site and leucine-rich repeat (NBS-LRR genes are the largest class of disease resistance genes cloned from plant with highly conserved domains, which can be used to facilitate the isolation of candidate genes associated with downy mildew resistance in IL5211S. Results Degenerate primers that were designed based on the conserved motifs in the NBS domain of resistance (R proteins were used to isolate NBS-type sequences from IL5211S. A total of 28 sequences were identified and named as cucumber (C. sativus = CS resistance gene analogs as CSRGAs. Polygenetic analyses separated these sequences into four different classes. Quantitative real-time polymerase chain reaction (qRT-PCR analysis showed that these CSRGAs expressed at different levels in leaves, roots, and stems. In addition, introgression from C. hystrix induced expression of the partial CSRGAs in cultivated cucumber, especially CSRGA23, increased four-fold when compared to the backcross parent CC3. Furthermore, the expression of CSRGA23 under P. cubensis infection and abiotic stresses was also analyzed at different time points. Results showed that the P. cubensis treatment and four tested abiotic stimuli, MeJA, SA, ABA, and H2O2, triggered a significant induction of CSRGA23 within 72 h of inoculation. The results indicate that CSRGA23 may play a critical role in protecting cucumber against P. cubensis through a signaling the pathway triggered by these molecules. Conclusions Four classes of NBS-type RGAs were

  16. Calcium channel structural determinants of synaptic transmission between identified invertebrate neurons.

    Science.gov (United States)

    Spafford, J David; Munno, David W; Van Nierop, Pim; Feng, Zhong-Ping; Jarvis, Scott E; Gallin, Warren J; Smit, August B; Zamponi, Gerald W; Syed, Naweed I

    2003-02-01

    We report here that unlike what was suggested for many vertebrate neurons, synaptic transmission in Lymnaea stagnalis occurs independent of a physical interaction between presynaptic calcium channels and a functional complement of SNARE proteins. Instead, synaptic transmission in Lymnaea requires the expression of a C-terminal splice variant of the Lymnaea homolog to mammalian N- and P/Q-type calcium channels. We show that the alternately spliced region physically interacts with the scaffolding proteins Mint1 and CASK, and that synaptic transmission is abolished following RNA interference knockdown of CASK or after the injection of peptide sequences designed to disrupt the calcium channel-Mint1 interactions. Our data suggest that Mint1 and CASK may serve to localize the non-L-type channels at the active zone and that synaptic transmission in invertebrate neurons utilizes a mechanism for optimizing calcium entry, which occurs independently of a physical association between calcium channels and SNARE proteins.

  17. Conservación de la biodiversidad en sistemas silvopastoriles de Matiguás y Rio Blanco (Matagalpa, Nicaragua

    Directory of Open Access Journals (Sweden)

    A. M. Pérez

    2006-01-01

    Full Text Available Con el fin de estudiar la relación entre uso del suelo y diferentes componentes de la biodiversidad de aves moluscos y plantas, se seleccionaron 12 usos de suelo en 41 fincas, 28 en Bulbul y 13 en Paiwas (Matagalpa, Nicaragua. Para el monitoreo de la vegetación se establecieron 10 parcelas en cada uso de suelo, siempre que fue posible, donde se estudió el número de árboles, densidad de tallos y arbustos, perfiles de altura del follaje, altura promedio del dosel, porcentaje de cobertura del dosel y cobertura del suelo. Para el estudio de las aves se realizaron puntos de conteo en todas las fincas seleccionadas. Para el estudio de los moluscos se muestreó en el 50% de las parcelas de vegetación y aves. Se realizaron 3 campañas de muestreo para el estudio de las aves, 2 para los moluscos y 1 para la vegetación. Se han identificado un total de 170 especies de plantas, 180 especies de aves y 56 especies de moluscos. Se ha concluido el estudio de la estructura de la vegetación y las comunidades de aves, y se ha muestreado en 113 parcelas distribuidas en 12 tipos de usos de suelo y 41 fincas, así como 10 parcelas en el Cerro Quirragua para un total de 123 parcelas. Los valores más altos de riqueza de especies en plantas, se encontraron en el bosque primario del Cerro Quirragua (S=46 y en los bosques riparios (S=43. En aves, se encontraron en los bosques riparios (S=74 y en bosques secundarios intervenidos (S=72. En moluscos, en bosques primarios (S=35, seguidos por los Tacotales (S=28. Los valores más altos de biodiversidad para plantas se encontraron en el bBosque primario de Quirragua (H´=3,34 y en los bosques riparios (H´=3,12. Para aves, en bosques riparios (H´=3,92 y bosques secundarios intervenidos (H´=3,86. Para moluscos, los bosques primarios (H’=2,93 y los bosques riparios (H’=2,46.

  18. First report of diarrheic shellfish toxins in mollusks from Buenos Aires province (Argentina associated with dinophysis spp.: evidence of okadaic acid, dinophysistoxin-1 and their acylderivatives

    Directory of Open Access Journals (Sweden)

    Eugenia A Sar

    2012-06-01

    Full Text Available In January 2010, the toxin-producing dinoflagellates Dinophysis acuminata and D. caudata (10³ cells·l-1 were detected in Mar Azul during routine plankton monitoring in Buenos Aires Province coastal waters, Argentina. Wild clams Mesodesma mactroides and Donax hanleyanus from Mar Azul intertidal beach, which are part of the diet for local inhabitants and tourists, tested positive with the offcial lipophilic mouse bioassay. This paper focuses on the detection of Diarrhetic Shellfsh Poison (DSP toxins in these samples using a HPLC-FLD pre column derivatization procedure. The data showed that shellfish were contaminated with complex DSP toxin profiles composed of Okadaic Acid (OA, Dinophysistoxin-1 (DTX-1, Acyl-Dinophysistoxin-1 (Acyl-DTX-1 and Acyl-Okadaic Acid (Acyl-OA. The DSP toxins found in this study produce diarrhea symptoms consistent with those experienced by patients who had ingested cooked shellfish in January. This is the first report of Acyl-derivatives in South American Atlantic shellfish samples and of OA in Argentinean shellfish samples.Primer reporte de toxinas diarreicas de moluscos en bivalvos de la Provincia de Buenos Aires (Argentina asociado con Dinophysis spp.: evidencia de Ácido Okadaico, Dinophysistoxina-1 y sus acyl-derivados. En enero de 2010, los dinoflagelados productores de toxinas Dinophysis acuminata y D. caudata (10³ cells·l-1 fueron detectados en Mar Azul durante un monitoreo rutinario de fitoplancton realizado en aguas costeras de la Provincia de Buenos Aires, Argentina. Mesodesma mactroides (almeja amarilla y Donax hanleyanus (berberecho del intermareal de Mar Azul, que son parte de la dieta de los habitantes del lugar y de turistas, dieron resultado positivo para toxinas lipofílicas mediante bioensayo ratón. Este trabajo está focalizado en la detección de Toxinas Diarreicas de Moluscos (DSP en muestras colectadas durante el evento de toxicidad usando un HPLC-FLD con procedimiento de derivatizaci

  19. Viabilidade de miracídios de Schistosoma mansoni, obtidos de fezes e de granulomas hepáticos de camundongos experimentalmente infectados com a linhagem BH Viability of Schislosoma mansoni miracidia obtained from feces and liver granuloma of experimental mice infected with the BH strain

    Directory of Open Access Journals (Sweden)

    Eliana Maria Zanotti-Magalhães

    1988-12-01

    Full Text Available Estudou-se comparativamente a viabilidade, em moluscos hospedeiros, de miracídios de Schistosoma mansoni de duas origens: de ovos eliminados com as fezes e de granulomas hepáticos. Procurou-se saber se havia efeito da origem sobre o número total de cercárias obtidas e sobre o período de eliminação de cercárias. Foram também verificados o período pré-patente da infecção dos moluscos, a sobrevivência do caramujo após a infecção e o sexo das cercárias eliminadas. Concluiu-se que: a o período pré-patente foi maior nos moluscos infectados por miracídios provenientes de granulomas hepáticos; b a sobrevivência dos moluscos após a infecção foi maior naqueles infectados por miracídios provenientes de granulomas hepáticos; c o número de cercadas eliminadas por molusco infectado com miracídios provenientes de granulomas hepáticos foi três vezes maior que o número de cercárias eliminadas por moluscos infectados com miracídios provenientes de ovos eliminados com as fezes.The viability of Schistosoma mansoni miracidia in host molluscs, obtained from two origins is examined: from eggs eliminated with feces of the definitive hosts and liver granuloma eggs. The effect of the origin of the miracidia on the number of cercariae and on the time of cercariae elimination was investigated. The prepatent period of cercariae elimination, snail survival after infection and the sex of the eliminated cercariae were also observed. The following results were obtained: a snails infected with miracidia from liver granuloma eggs took longer to begin to eliminate cercariae; b snail survival after infection was longer in the group infected with miracidia from liver granuloma eggs; c the total number of cercariae produced by the snail group infected with miracidia from liver granuloma eggs was three times that of the group infected with miracidia from eggs eliminated with feces.

  20. Planorbidae, Lymnaeidae and Physidae of Ecuador (Mollusca: Basommatophora

    Directory of Open Access Journals (Sweden)

    W Lobato Paraense

    2004-06-01

    Full Text Available In the course of a trip to Ecuador I had the opportunity of collecting topotypic specimens of the following nominal species of pulmonate molluscs: Biomphalaria cousini Paraense, 1966; Planorbis equatorius Cousin, 1887; P. canonicus Cousin, 1887; Lymnaea cousini Jousseaume, 1887 and P. boetzkesi Miller, 1879. Additional findings were: Helisoma trivolvis (Say, 1817, Biomphalaria peregrina (Orbigny 1835, Drepanotrema anatinum (Orbigny, 1835, D. kermatoides (Orbigny, 1835, D. lucidum (Pfeiffer, 1839, D. surinamense (Clessin, 1884, Lymnaea columella Say, 1817 and Physa acuta Draparnaud, 1805. P. boetzkesi and P. canonicus are considered junior synonyms of Gyraulus hindsianus (Dunker, 1848 and Biomphalaria peregrina (Orbigny, 1835, respectively.

  1. One-trial reward learning in the snail Lymnea stagnalis.

    Science.gov (United States)

    Alexander, J; Audesirk, T E; Audesirk, G J

    1984-01-01

    We present evidence that the pond snail Lymnaea stagnalis is capable of aquisition and extensive retention of an appetitively reinforced feeding response after only a single training trial. Food-deprived snails presented with a single pairing of a phagostimulant (a mixture of sucrose and casein digest) and a novel, non-food chemostimulus (amyl acetate) subsequently made feeding responses to the amyl acetate and retained the association for at least 19 days. This demonstration of one-trial, non-aversive classical conditioning enhances the utility of Lymnaea stagnalis as a model system for the detailed analysis of neural mechanisms underlying plasticity.

  2. Dermoscopic patterns of molluscum contagiosum: a study of 211 lesions confirmed by histopathology

    OpenAIRE

    Mayra Ianhez; Silmara da Costa P Cestari; Mauro Yoshiaki Enokihara; Maria Bandeira de Paiva Melo Seize

    2011-01-01

    FUNDAMENTOS: Embora de fácil diagnóstico, o molusco contagioso pode apresentar-se como lesões inflamadas, únicas ou pequenas de difícil diagnóstico. OBJETIVO: Descrever características dermatoscópicas do molusco contagioso e comparar achados do exame clínico e dermatoscópico. MÉTODOS: Avaliou-se clínica e dermatoscopicamente lesões confirmadas pela histopatologia em 57 pacientes. RESULTADOS: Nos exames clínico e dermatoscópico de 211 lesões, foram visualizados orifícios em 50,24% e 96,68% das...

  3. Distribucion arborea de los gastropodos cerithidea montagnei (mollusca potamidae y littorina Spp. (Mollusca, Littorinidae en el manglar de Mata de Limón, Costa Rica

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    Édgar Suarez B

    2016-03-01

    Full Text Available En el manglar de Mata de Limón, Puntarenas, Costa Rica, se estudió la distribución y preferencia por el susbtrato arbóreo de gastrópodos C. montagnei y Littorina spp. en cuatro especies de mangle, según la cantidad de moluscos observados en cada árbol y la cantidad de árboles con presencia o ausencia de ellos, en el período de setiembre de 1982 a junio de 1983. El orden de preferencia mostrado por ambos grupos de moluscos fue: 1 Rhizophora mangle, 2 Avicennia germinans, 3Pelliciera rhizophorae y 4 Laguncularia racemosa. Se discuten las posibles razones de esta preferencia. Cerithidea montagnei presentó una mayor distribución horizontal, así como una mayor abundancia respecto de Littorina spp.

  4. Evaluacion comparativa de dos tipos de muestreo en chucheca (Grandiarca grandis) y piangua (Anadara tuberculosa), en el Golfo de Nicoya, Costa Rica (ING)

    OpenAIRE

    Bolaños Montero, Juan

    2016-01-01

    A comparative study was carried out in order to test the statistic goodness of two sampling methods, working with mollusks in the mangrove ecosystem. Stratified random sampling proved to be better than unrestrained random sampling. Se realizó un estudio comparativo para probar la bondad estadística de dos métodos de muestreo de moluscos en el ecosistema de manglar. El muestreo por estratos resultó ser mejor que el muestreo irrestricto al azar.

  5. Nuevas adiciones de bivalvos a la malacofauna marina peruana

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    Carlos Paredes

    2014-06-01

    Full Text Available Cuatro especies de moluscos bivalvos marinos, Nuculana (Jupiteria cuneata (Sowerby, 1833, Isognomon (Isognomón janus Carpenter, 1857, Ostrea conchaphila Carpenter, 1857 y Mysella (Rochefortia molinae Ramorino, 1968 se reportan por primera vez para el mar peruano. Se incluye datos sobre la distribución geográfica y el hábitat de cada una de las especies.

  6. fresco: análisis comparativo

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    D. Hernández Moreno

    2005-01-01

    Full Text Available La contaminación del medio marino por metales pesados puede afectar a la calidad de los alimentos destinados al ser humano. Los moluscos, como organismos filtradores, tienden a acumular metales en sus tejidos, y este hecho puede suponer un serio riego para el consumidor. En el presente estudio se han analizado los niveles de cuatro metales (zinc, plomo, cobre y cadmio en tres moluscos (almeja, berberecho y navaja comercializados en fresco en España, empleando digestión por vía seca y voltamperometría de redisolución anódica. Comparando entre especies, las mayores concentraciones se obtuvieron siempre en las almejas, y en el hepatopáncreas de los moluscos más que en el músculo. Los resultados han permitido comprobar que estos alimentos no presentan concentraciones problemáticas de metales y que su consumo moderado no constituye un riesgo para el consumidor

  7. Interference microscopy under double-wavelet analysis: a new approach to studying cell dynamics

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Pavlov, A N; Brazhe, Nadezda;

    2005-01-01

    This Letter combines a novel experimental approach to the study of intracellular processes with a newly developed technique for multimode time-series analysis. Experiments are performed on isolated pond snail (Lymnaea stagnalis) neurons. Local variations in the cellular refractive index as detect...

  8. Structural and functional studies of the modulator NS9283 reveal agonist-like mechanism of action at α4β2 nicotinic acetylcholine receptors

    DEFF Research Database (Denmark)

    Olsen, Jeppe A; Ahring, Philip K; Kastrup, Jette Sandholm Jensen;

    2014-01-01

    Modulation of Cys loop receptor ion channels is a proven drug discovery strategy, but many underlying mechanisms of the mode of action are poorly understood. We report the x-ray structure of the acetylcholine-binding protein from Lymnaea stagnalis with NS9283, a stoichiometry selective positive m...

  9. Neuro-endocrine disruption in molluscs

    DEFF Research Database (Denmark)

    Holbech, Henrik; Bech Sanderhoff, Lene; Waller, Stine P.

    efficient and fast in vivo system using embryos of the freshwater pulmonate gastropod Lymnaea stagnalis (the great pond snail). It is known that serotonin and dopamine are involved in many reproductive processes in molluscs Incl. egg maturation and spawning and that pedal ciliary activity causing L...

  10. Morphological and molecular characterization of lymnaeid snails and their potential role in transmission of Fasciola spp. in Vietnam.

    Science.gov (United States)

    Dung, Bui Thi; Doanh, Pham Ngoc; The, Dang Tat; Loan, Ho Thi; Losson, Bertrand; Caron, Yannick

    2013-12-01

    Freshwater snails of the family Lymnaeidae play an important role in the transmission of fascioliasis worldwide. In Vietnam, 2 common lymnaeid species, Lymnaea swinhoei and Lymnaea viridis, can be recognized on the basis of morphology, and a third species, Lymnaea sp., is known to exist. Recent studies have raised controversy about their role in transmission of Fasciola spp. because of confusion in identification of the snail hosts. The aim of this study is, therefore, to clarify the identities of lymnaeid snails in Vietnam by a combination of morphological and molecular approaches. The molecular analyses using the second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA clearly showed that lymnaeids in Vietnam include 3 species, Austropeplea viridis (morphologically identified as L. viridis), Radix auricularia (morphologically identified as L. swinhoei) and Radix rubiginosa (morphologically identified as Lymnaea sp.). R. rubiginosa is a new record for Vietnam. Among them, only A. viridis was found to be infected with Fasciola spp. These results provide a new insight into lymnaeid snails in Vietnam. Identification of lymnaeid snails in Vietnam and their role in the liver fluke transmission should be further investigated.

  11. ANALIZAR TRES ESPECIES DE CARACOLES QUE ACTÚEN COMO POSIBLES HOSPEDEROS INTERMEDIARIOS DE LA FASCIOLA HEPÁTICA EN LA REGIÓN AREQUIPA - 2013

    OpenAIRE

    CUADROS MEDINA, SANTIAGO BALTAZAR

    2015-01-01

    CARACOL MELANOIDES TUBERCULATA ORIGEN Y HÁBITAT SINONIMIAS CARACTERÍSTICAS MORFOLÓGICAS MANTENIMIENTO ALIMENTACIÓN COMPORTAMIENTO REPRODUCCIÓN FASCIOLA HEPÁTICA CICLO BIOLÓGICO GÉNERO PHYSA GÉNERO LYMNAEA GÉNERO MALAYSIAN TRUMPET SNAIL ECOLOGÍA HÁBITAT PARÁSITOS LAS PLAGAS AGRÍCOLAS

  12. Computer simulation of early embryonic development

    NARCIS (Netherlands)

    Bezem, J.J.; Raven, Chr.P.

    1975-01-01

    A simple model, formulated in terms of elementary geometry, is presented, describing the early development of Lymnaea stagnalis. It includes the main morphogenetic processes active at this stage: cell division, cell flattening and differentiation. Though the model has been designed primarily to fit

  13. AcEST: DK955684 [AcEST

    Lifescience Database Archive (English)

    Full Text Available y subunit OS=Pagothenia berna... 108 3e-23 sp|P85837|FRIH_TRENE Ferritin, heavy subunit OS=Trematomus newne....itin OS=Lymnaea stagnalis PE=2 SV=2 109 1e-23 sp|P85838|FRIH_PAGBE Ferritin, heav

  14. Interference microscopy under double-wavelet analysis: A new approach to studying cell dynamics

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Pavlov, A.N.; Brazhe, N.A.

    2005-01-01

    This Letter combines a novel experimental approach to the study of intracellular processes with a newly developed technique for multimode time-series analysis. Experiments are performed on isolated pond snail (Lymnaea stagnalis) neurons. Local variations in the cellular refractive index as detect...

  15. How do the molluscivorous beetles Carabus granulatus and Phosphuga atrata (Insecta, Coleoptera) deal with sinistral and dextral prey?

    NARCIS (Netherlands)

    Bergamin, Susan; Smits, Anne

    2015-01-01

    Predators of asymmetric prey (such as snails) are often asymmetric themselves or display a predation behaviour that is adapted to the asymmetry of their prey. We studied predation of sinistral and dextral forms of the freshwater snail Lymnaea stagnalis (Linnaeus, 1758) by two snail-feeding beetle sp

  16. A novel monoclonal antibody-based immunoenzymatic assay for epidemiological surveillance of the vector snails of Fasciola hepatica (Trematoda: Digenea).

    Science.gov (United States)

    Alba, Annia; Hernández, Hilda M; Marcet, Ricardo; Vázquez, Antonio A; Figueredo, Mabel; Sánchez, Jorge; Otero, Oscar; Sarracent, Jorge

    2015-02-01

    Fasciolosis is a globally distributed snail-borne disease which requires economic consideration due to its enormous impact on veterinary medicine. During recent decades, this parasitosis has also shown increasing prevalence in human populations worldwide. The dissemination and successful transmission of fasciolosis ultimately depends on the existence of susceptible snails that act as intermediate hosts. Therefore, to accomplish effective control of this disease, surveillance and detection of the infected intermediate host would be essential. The screening of trematodes within snails using classical parasitological examination of the larvae can be unreliable (sensitivity and specificity vary depending on the time of infection and the experience of the observer) and relatively costly when using molecular biological methods during large-scale monitoring. Here we propose a novel monoclonal antibody-based immunoenzymatic assay to detect ongoing Fasciola hepatica infection in lymnaeid snails. Anti-F. hepatica rediae mouse monoclonal antibodies were generated and used to develop a double monoclonal antibody-based ELISA for parasite detection. Fasciola hepatica-infected and uninfected laboratory-reared Galba cubensis and Pseudosuccinea columella were used for assessment of the developed ELISA. Experimentally infected snails were dissected and examined for parasite larvae as the "gold standard" method. Sensitivity results were 100% for both snail species, while specificity was 98% for G. cubensis and 100% for P. columella. No cross-reactivity was detected in lymnaeids infected with Trichobilharzia sp. or Cotylophoron sp. The ELISA enabled detection of the infection from day 8 p.i. in G. cubensis while in P. columella it was noted as early as day 4. To our knowledge no previous immunoassays have been reported to detect helminth-infected snails and the developed sandwich ELISA method is therefore suggested for infection status validation in natural populations of lymnaeid

  17. Susceptibilidad a insectos en selecciones y variedades de annona muricata l. y persea americana m. en Puerto Rico

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    Irma Cabrera

    2001-01-01

    Full Text Available En Puerto Rico se han reportado varios insectos en las guanábanas (Annona muricata L. y los aguacates (Persea americana M, sin embargo los de mayor importancia son el barrenador de la semilla Bephratelloides cubensis (A. y Apate monacha (F. en A. muricata y Pseudacysta persea (F. en P. americana. El objetivo principal de esta investigación fue determinar la incidencia de B. cubensis y A. monacha en seis selecciones de guanábana y en siete variedades de aguacate. De las evaluaciones realizadas en A. muricata, se observó que las selecciones IV-10, VII-14 y VI-1 mostraron la mayor incidencia y la IV-16 mostró la menor incidencia de B. cubensis en relación al número de barrenos por fruta. En cuanto a la incidencia de A. monacha en A. muricata las selecciones IV-16, IV-2, IV-3, VII-14 presentaron la mayor incidencia de barrenos por árbol. En las evaluaciones realizadas en Persea americana se seleccionaron las variedades Ávila, Semil 34, Wilson Popenoe, Pollock, Candelaria, Semil 43 y Butler como las variedades comerciales más sembradas en Puerto Rico. Se observó que la variedad Avila obtuvo el mayor número de huevos, ninfas, hembras y machos de P. persea por hojas comparadas con las demás variedades. Respecto al número de hojas infestadas por árbol se encontró valores significativos (P≤0,01 en la variedad Avila. Resultando tener un 90% de las hojas dañadas. No se observó que las variedades evaluadas tuviese baja o ninguna preferencia a P. Persea

  18. Hyphomycetes com conidioma dos tipos esporodóquio e sinema associados a folhas de Cedrela fissilis (Meliaceae, em Maringá, PR, Brasil Hyphomycetes with sporodochial and synnematous conidiomata associated with leaves of Cedrela fissilis (Meliaceae in Maringá, PR, Brazil

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    Luís Fernando Pascholati Gusmão

    1997-12-01

    Full Text Available Folhas vivas e em decomposição de Cedrela fissilis Veil, foram coletadas, de janeiro a novembro de 1993, no Horto Florestal "Dr. Luiz Teixeira Mendes", Município de Maringá, PR, Brasil (23º25'S, 51º25'W, com a finalidade de isolar Hyphomycetes. As amostras foliares passaram pela técnica de lavagem vigorosa com água destilada esterilizada e plaqueamento em câmaras-úmidas. Foram isoladas três espécies com conidioma do tipo esporodóquio, Epicoccum nigrum Link, Volutella minima Hõhn. e Wiesneriomyces laurinus (Tassi Kirk, e três com conidioma do tipo sinema, Menisporopsis theobromae S. Hughes, Thozetella cristata Piroz. & Hodges e T. cubensis Castaneda & Arnold. Todas as espécies ocorreram no folhedo sendo predominantes M. theobromae, T. cristata e W. laurinus. Em folhas vivas foram isoladas apenas E. nigrum e V. minima. São apresentadas, para cada espécie, descrição, distribuição geográfica, comentários e ilustrações. Todas as espécies estão sendo citadas pela primeira vez para o Estado do Paraná; T. cubensis é referida pela primeira vez para o Brasil.With the aim to study Hyphomycetes, leaves of Cedrela fissilis Veil, were collected from January to November of 1993, in the "Horto Florestal Dr. Luiz Teixeira Mendes", Municipality of Maringá, PR, Brazil (23º25' S, 51º25' W. The leaves were prepared by washing with serial changes of sterile distilled water and incubated in moist chambers. Three species with sporodochial conidiomata, Epicoccum nigrum Link, Volutella minima Hõhn. and Wiesneriomyces laurinus (Tassi Kirk and three with synnematous type, Menisporopsis theobromae S. Hughes, Thozetella cristata Piroz. & Hodges and T. cubensis Castaneda & Arnold were isolated. All these species colonize C. fissilis leaf litter with M. theobromae, T. cristata, and W. laurinus being the most commonly found. From living leaves of C. fissilis only is. nigrum and V minima were isolated. Descriptions, geographical distributions

  19. Production of Shistosoma mansoni cercariae by Biomphalaria glabrata from a focus in Belo Horizonte, Minas Gerais Produção de cercárias de Schistosoma mansoni por Biomphalaria glabrata de foco em Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1994-12-01

    Full Text Available The snail density, levels of infection and the monthly production of Schistosoma mansoni cercariae by Biomphalaria glabrata were determined in a focus of Barreiro de Baixo (Belo Horizonte, MG, Brazil. During a period of 38 months (1984 to 1987 5,366 snails were collected of which 324 (6.03% were infected with S. mansoni. The total number of cercariae shed was 5,667,312. Each snail shed an average of 17,422 cercariae during the time that it was under study in the laboratory. The greatest longevity of infected snails was 218 days. Natural cure was observed in 42 (12.9% of the infected specimens about 130 days after collection. The average snail density in the focus during the period of study was 16.3 snails per scoop. The shedding of cercariae by snails collected from the field was compared with laboratory bred specimens infected in mass with the LE strain of S. mansoni from Belo Horizonte. The laboratory infected snails shed an average of 6,061 cercariae each, a value 2.8 times less than the field specimens due to a shorter life span. The prevalence of schistosomiasis in the focus was 14.3%.A densidade planorbídica, as taxas de infecção e a produção mensal de cercárias de Schistosoma mansoni por Biomphalaria glabrata, foram determinadas em foco do Barreiro de Baixo (Belo Horizonte MG, Brasil. Durante 38 meses, de 1984 a 1987, foram capturados 5.366 moluscos dentre os quais 324 (6,03% estavam infectados com o S. mansoni. O total de cercárias eliminadas foi de 5.667.312. Cada molusco eliminou em média 17.422 cercárias durante sua permanência no laboratório. A maior longevidade dos moluscos infectados foi de 218 dias. Foi observada a cura natural de 42 (12,9% dos exemplares infectados, após cerca de 130 dias de captura. A densidade planorbídica média, no foco durante esse período foi de 16,3 moluscos por conchada. A eliminação de cercárias pelos moluscos do campo foi comparada com a de exemplares criados no laboratório, infectados

  20. The spiny dogfish ('cação-bagre'): description of an envenoming in a fisherman, with taxonomic and toxinologic comments on the Squalus gender.

    Science.gov (United States)

    Haddad, Vidal; Gadig, Otto Bismarck Fazzano

    2005-07-01

    The authors report an injury caused by a spiny dogfish (Squalus sp) in a professional fisherman that was got hurt in the left hand for a spine in the dorsal fin of the fish and felt excruciating local pain for 6 h and manifested local edema and erythema. The sharks of the Squalus gender, in a similar way to the gender Heterodontus, present two spines in position previous to the dorsal fins, with channels presenting a whitish mass, composed of great and vacuolated cells that produce venom. The Squalus gender has a complex taxonomy, with five nominal species mentioned in Brazil: S. acanthias, S. blainvillei, S. cubensis, S. megalops and S. mitsukurii. The species associated to the injury belongs to the group 'megalops/cubensis'. A detailed study on the taxonomy and toxinology of the Squalus gender in Brazil would be of vital importance in the resolution of those problems and it would serve as subsidy for any other works involving their representatives, besides with aspects of envenoming that this gender can cause and that has rare citations in the literature.

  1. Freshwater sponges (Porifera, Demospongiae in a benthic filter feeding community at the Guanacaste Dry Forest, Costa Rica Esponjas continentais (Porifera, Demospongiae em uma comunidade bêntica filtradora na Floresta Decidual de Guanacaste, Costa Rica

    Directory of Open Access Journals (Sweden)

    Cecilia Volkmer-Ribeiro

    2009-12-01

    Full Text Available The freshwater sponges Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973, Radiospongilla crateriformis (Potts, 1882, Spongilla cenota Penney & Racek (1968 and Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974 compose with the sphaerid bivalve Eupera cubensis (Prime, 1865 and several Phylactolaemata bryozoans a benthic filter feeding community living in seasonal lentic and lotic habitats with high Particulate Organic Carbon (POC, low conductivity and acid pH within the Costa Rica Dry Forest biome. The sponge specimens gathered led to the re-description of the four species.As esponjas de água doce Trochospongilla variabilis Bonetto & Ezcurra de Drago (1973, Radiospongilla crateriformis (Potts, 1882, Spongilla cenota Penney & Racek (1968 e Corvoheteromeyenia heterosclera (Ezcurra de Drago, 1974 compõem, com o bivalve esferídeo Eupera cubensis (Prime, 1865 e diversos briozoários Phylactolaemata, uma comunidade bêntica de filtradores em ambientes sazonais lênticos e lóticos com alto Carbono Orgânico Particulado (POC, baixa condutividade e pH ácido no bioma da Floresta Decidual da Costa Rica. Os espécimes de esponjas coligidos conduziram à redescrição das quatro espécies.

  2. Grupos tróficos de peixes demersais da plataforma continental interna de Ubatuba, Brasil: I. Chondrichthyes Throphic groups of demersal fish community from the continental shelf: Ubatuba, Brazil. I. Chrondrichthyes

    Directory of Open Access Journals (Sweden)

    Lucy Satiko Hashimoto Soares

    1992-01-01

    Full Text Available Com o objetivo de detectar grupos tróficos, foram analisadas amostras de conteúdos estomacais de sete espécies de peixes cartilaginosos. Os exemplares foram coletados no período de Outubro/85 a Julho/87 na plataforma interna de Ubatuba, SP, Brasil (da costa, até a isóbata de 50 m. A importância dos itens alimentares foi analisada através da freqüência numérica (FN e da freqüência de ocorrência (FO. As espécies foram agrupadas em três grupos distintos: Piscívoros: Squalus cubensis; comedores de peixes e crustáceos bentônicos: Raja castelnaui, Raja cyclophora, Raja agassizi; comedores de invertebrados bentônicos: Psammobatis glansdissimilis, Rhinobatos horkelii, Zapteryx brevirostris.Stomach contents of seven cartilaginous fish species were analysed with the aim to detect trophic groups. Sampling was effectuated between October/85 and July/87 off the coast of Ubatuba (São Paulo, Brazil in waters up 50 m depth. The relative importance of different components of the diet was expressed as a percentage frequency of occurrence and percentage number. The seven species were grouped in: fish feeders - Squalus cubensis; benthonic crustacean and fish feeders - Raja castelnaui, Raja cyclophora, Raja agassizi; benthonic invertebrate feeders - Rhinobatos horkelii, Zapteryx brevirostris, Psammobatis glansdissimilis.

  3. Variation of snail's abundance in two water bodies harboring strains of Pseudosuccinea columella resistant and susceptible to Fasciola hepatica miracidial infection, in Pinar del Río Province, Cuba

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    Alfredo Gutiérrez

    2005-11-01

    Full Text Available The abundance of freshwater snails in two rural sites of Pinar del Río, Cuba, which harbor Pseudosuccinea columella susceptible and resistant to miracidia of Fasciola hepatica was followed for one year. Susceptible snails were found in the most anthropic site (IPA whereas the resistant population inhabited the most preserved one (El Azufre. Only two snail species coexisted with P. columella at IPA site (Physa cubensis and Tarebia granifera while five species were found at El Azufre, including an endemic from that province (Hemisinus cubanianus. Populations of both resistant and susceptible snails showed stable densities throughout the year, although the susceptible strain attained higher abundance. The highest densities were observed in April-May 2004 for the susceptible population whereas the resistant strain attained its highest abundance in January 2004. No record of Fossaria cubensis was made and the thiarid T. granifera occurred only at low densities. One of the sampled sites (IPA meets all the conditions for the first report of P. columella naturally infected with larvae of F. hepatica.

  4. Winter distribution, density and size of Mesodesma mactroides (Bivalvia, Mactracea in Monte Hermoso beach (Argentina

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    Sandra Marcela Fiori

    2004-03-01

    Full Text Available The yellow clam Mesodesma mactroides (Deshayes, 1854 is a seasonal migrant that moves in spring to the sandy upper intertidal level. In this paper we analyze the spatial distribution of density and mean shell size of the yellow clam population in Monte Hermoso beach (Argentina in winter 1995, i.e., three months before the mass mortality occurred in November 1995. Sampling covered 32 km of beach, with a regular design of 22 transects. The major environmental gradient in the beach was determined using principal component analysis (PCA on the correlation matrix of the environmental data (beach morphology, slope, and sand granulometry. Correlation analysis was used to assess the relationship between the score of a site (transect on the first and second principal component, and clam mean density and mean shell size. Most of the beach seems to be habitable for clams, their spatial heterogeneity not having been explained by the measured variables since, although the first axis of the PCA has demonstrated an E-W physical gradient, clam density was not in correlation with it. Density was maximum near the piers, even though these are points with high tourist activity. It seems that non-extractive touristic activities do not affect population density but rather mean shell size, probably due to reduction of growth rates. The abundance of the winter population, as compared with the assessment done after the mass mortality of November, strongly suggests that a great part of the population was overwintering in the intertidal fringe.O molusco Mesodesma mactroides (Deshayes, 1854 é uma espécie migrante sazonal que na primavera move-se para o nível entremarés superior da praia. Neste estudo, analisamos a distribuição espacial da densidade e o tamanho médio da população do bivalve na praia de Monte Hermoso (Argentina no inverno de 1995, i. é, três meses antes da mortalidade massiva desses moluscos, acontecida em novembro de 1995. A amostragem cobriu 32

  5. FIELD TRIALS OF MOLLUSCICIDE (WL 8008 IN BILHARZIASIS CONTROL PROJECT AREA, IN IRAN

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    J. Massoud

    1973-09-01

    Full Text Available Field trials of molluscicide WL8008 (N-tritylmorpholine were carried out in Khuzestan, Iran. The liquid 2 (FX/28, a 16.5 w/v emulsifiable concentrate in tetrachloroethylene in concentrations of 0.25 ppm and 0.5 ppm was used against Bulinus truncatus and Lymnaea gedrosiana in standing and running water systems . Bio-assay tests and laboratory experiments were made parallel to the field trials. Only a few of the B.truncatus were affected by 0.25 ppm of N-tritylmorpholine, but L.gedrosiana proved to be more susceptible to the chemical and an almost complete kill of L.gedrosiana was achieved. A concentration of 0.5 ppm completely killed both B.truncatus and L.gedrosiana, but had no effect on egg-masses. N-trityl-morpholine may play an important part in future snail control projects, particularly on Lymnaea snails.

  6. LARVAS DE DIGENEA EN Melanoides tuberculata (GASTROPODA: THIARIDAE EN MEDELLÍN, COLOMBIA Larval stages of digenea from Melanoides tuberculata (Gastropoda: Thiaridae in Medellín, Colombia

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    DANIELA VERGARA

    Full Text Available Se describen las larvas de digeneos que se obtuvieron en Melanoides tuberculata (Gastropoda: Thiaridae, molusco dulceacuícola del que se colectaron 125 especímenes en el lago del Jardín Botánico Joaquín Antonio Uribe de Medellín. En el laboratorio se individualizaron y se estimuló la emisión cercariana con una fuente luminosa. El 9,6 % de los caracoles emitió cercarias. Los moluscos emisores se sacrificaron para obtener los demás estadios larvarios. Las larvas se montaron al microscopio, se midieron y luego se dibujaron. Los caracteres morfológicos permitieron establecer la presencia de Centrocestus formosanus (Heterophyidae y de dos Philophthalmidae. Uno de estos es primer registro para Colombia. Se confirma la sensibilidad de M. tuberculata a infecciones por digeneos, así como la especificidad de los filoftálmidos por moluscos hospedadores de la superfamilia Cerithioidea.The larvae of two trematodes found in the freshwater mollusk Melanoides tuberculata (Gastropoda: Thiaridae are described. 125 snails from the Medellin’s Botanical Garden Joaquín Antonio Uribe were collected. In the laboratory, each individual was placed alone and stimulated with light in order to have cercaria emission. 9.6% of the snails released cercariae. These were separated in three morphologies. From each one, 15 individuals were measured and drawn. Photographs were taken. Based on their morphological characteritics the presence of Centrocestus formosanus (Heterophyidae was determined. The other two morphologies were classified in the family Philophthalmidae. One of them constitutes the first register for Colombia. The sensibility of M. tuberculata to infections by digeneans, and the specificity of the family Philophthalmidae to mollusk hosts of the superfamily Cerithioidea are confirmed

  7. First record of epibionts peritrichids and suctorians (Protozoa, Ciliophora on Pomacea lineata (Spix, 1827

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    Roberto Júnio Pedroso Dias

    2006-09-01

    Full Text Available This study made a survey on the ciliate protozoans from Peritrichid and Suctorian taxa, epibionts of Pomacea lineata (Spix, 1827 (Ampullariidae. Fifty mollusks were collected in places of irrigation ditches and shell was scraped with a scalpel and the extracted material was analyzed in vivo by light microscopy. All examined mollusks presented epibiont ciliates on their shells. For the first time epibiont ciliates in P. lineata was record. Seven genera of ciliates: five peritrichids and two suctorians, were identified and classified within the subclass Peritrichia: Carchesium Ehrenberg, 1838 (Vorticellidae, Epistylis Ehrenberg, 1830 (Epistylidae, Opercularia Stein, 1854 (Operculariidae, Vaginicola Lamarck, 1816 (Vaginicolidae and Vorticella Linnaeus, 1767 (Vorticellidae; and Suctoria: Acineta Ehrenberg,1834 (Acinetidae and Tokophrya Bütschli,1889 (Tokophrydae. The results showed that P. lineata constitute the microenvironment of a ciliate protozoan community that presents complex trophic interactions.O objetivo do presente estudo foi realizar um levantamento dos protozoários ciliados dos táxons Peritrichia e Suctoria, epibiontes de Pomacea lineata (Spix, 1827 (Ampullariidae. Cinqüenta moluscos foram coletados em ambientes de vala de irrigação, em Juiz de Fora, Minas Gerais. As conchas dos moluscos foram raspadas com bisturi e o material extraído analisado in vivo sob o microscópio de luz. Todos os moluscos examinados apresentaram ciliados epibiontes em suas conchas. Registra-se pela primeira vez ciliados epibiontes em P. lineata. Sete gêneros de ciliados: cinco peritríquios e dois suctórios foram identificados e classificados nas subclasses Peritrichia : Carchesium Ehrenberg, 1838 (Vorticellidae, Epistylis Ehrenberg, 1830 (Epistylidae, Opercularia Stein, 1854 (Operculariidae, Vaginicola Lamarck, 1816 (Vaginicolidae e Vorticella Lìnnaeus, 1767 (Vorticellidae; e Suctoria: Acineta Ehrenberg, 1834 (Acinetidae e Tokophrya Bütschli, 1889

  8. El macrozoobentos de fondo blando frente a la bahía de Catarindo durante el fenómeno "El Niño 1997-98"

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    Pastor Coayla

    2014-06-01

    Full Text Available Se analizó los cambios del macrozoobentos durante el período enero de 1997 a julio de 1998 en la estación fija de Catarindo (Moliendo -Arequipa, ubicada en los 17°01'13" LS y 72°02'19" LW. Las muestras fueron tomadas con una draga van Veen de 0,04 m2, a 34 metros de profundidad. Se registró un total de 50 especies diferentes, correspondientes a poliquetos, moluscos, crustáceos y otros; observándose en 1998 un incremento de especies de moluscos y crustáceos que no estuvieron presentes en 1997. Durante "El Niño 1997-98", predominaron numéricamente el grupo de los poliquetos, siendo las especies más importantes Prionospío peruana, Nephtys multícirrata, Goniada sp., y Leitoscoloplos chilensís. La mayor densidad del macrozoobentos se registró en la primavera de 1997 y parte del verano de 1998, siendo P. peruana la de mayor densidad. La biomasa durante 1997 se presentó fluctuante y la mayor fue aportada por el grupo de los poliquetos, en tanto que en 1998 el incremento de la biomasa fue dada principalmente por los moluscos. La diversidad presentó valores entre 1,5 y 3,2 bits, los mayores valores fueron registrados durante el verano e invierno de 1997 y a finales del verano e inicios del otoño de 1998.

  9. Planorbidae, Lymnaeidae and Physidae of Peru (Mollusca: Basommatophora

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    Paraense W Lobato

    2003-01-01

    Full Text Available In the course of several trips to Peru I had the opportunity of collecting topotypic specimens of Biomphalaria andecola (Orbigny, 1835, B. helophila (Orbigny, 1835, B. pucaraensis (Preston, 1909, Drepanotrema limayanum (Lesson, 1830, D. kermatoides (Orbigny, 1835, and Lymnaea viatrix Orbigny, 1835, besides B. tenagophila (Orbigny, 1835, Helisoma trivolvis (Say, 1817, H. duryi (Wetherby, 1879, Physa acuta Draparnaud, 1801, and seemingly P. peruviana Gray, 1828. B. pucaraensis is considered a junior synonym of B. peregrina (Orbigny, 1835.

  10. A homolog of the vertebrate pituitary adenylate cyclase-activating polypeptide is both necessary and instructive for the rapid formation of associative memory in an invertebrate.

    Science.gov (United States)

    Pirger, Zsolt; László, Zita; Kemenes, Ildikó; Tóth, Gábor; Reglodi, Dóra; Kemenes, György

    2010-10-13

    Similar to other invertebrate and vertebrate animals, cAMP-dependent signaling cascades are key components of long-term memory (LTM) formation in the snail Lymnaea stagnalis, an established experimental model for studying evolutionarily conserved molecular mechanisms of long-term associative memory. Although a great deal is already known about the signaling cascades activated by cAMP, the molecules involved in the learning-induced activation of adenylate cyclase (AC) in Lymnaea remained unknown. Using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy in combination with biochemical and immunohistochemical methods, recently we have obtained evidence for the existence of a Lymnaea homolog of the vertebrate pituitary adenylate cyclase-activating polypeptide (PACAP) and for the AC-activating effect of PACAP in the Lymnaea nervous system. Here we first tested the hypothesis that PACAP plays an important role in the formation of robust LTM after single-trial classical food-reward conditioning. Application of the PACAP receptor antagonist PACAP6-38 around the time of single-trial training with amyl acetate and sucrose blocked associative LTM, suggesting that in this "strong" food-reward conditioning paradigm the activation of AC by PACAP was necessary for LTM to form. We found that in a "weak" multitrial food-reward conditioning paradigm, lip touch paired with sucrose, memory formation was also dependent on PACAP. Significantly, systemic application of PACAP at the beginning of multitrial tactile conditioning accelerated the formation of transcription-dependent memory. Our findings provide the first evidence to show that in the same nervous system PACAP is both necessary and instructive for fast and robust memory formation after reward classical conditioning.

  11. Fasciola hepatica: epidemiology, perspectives in the diagnostic and the use of geoprocessing systems for prevalence studies

    OpenAIRE

    Marcos André Aleixo; Deivid França Freitas; Leonardo Hermes Dutra

    2015-01-01

    Fasciola hepatica is a parasite that is located in the liver of ruminants with the possibility to infect horses, pigs and humans. The parasite belongs to the Trematoda class, and it is the agent causing the disease called fasciolosis. This disease occurs mainly in temperate regions where climate favors the development of the organism. These conditions must facilitate the development of the intermediate host, the snail of the genus Lymnaea. The infection in domestic animals can lead to decreas...

  12. The potential utility of nested PCR for investigation of Coxiella burnetii in Iranian snails

    OpenAIRE

    2016-01-01

    Objective: To detect the prevalence of Coxiella burnetii (C. burnetii) in two species of snails consisted of Lymnaea palustris (L. palustris) and Pomacea canaliculata (P. canaliculata) by using nested PCR method in Chaharmahel Va Bakhtiari Province which is located in the southwest of Iran. Methods: A total of 160 snail samples consisted of 100 L. palustris and 60 P. canaliculata were collected from 4 rice paddy fields in the southwest of Iran between June and August 2014. S...

  13. Octopamine increases the excitability of neurons in the snail feeding system by modulation of inward sodium current but not outward potassium currents

    OpenAIRE

    2005-01-01

    Abstract Background Although octopamine has long been known to have major roles as both transmitter and modulator in arthropods, it has only recently been shown to be functionally important in molluscs, playing a role as a neurotransmitter in the feeding network of the snail Lymnaea stagnalis. The synaptic potentials cannot explain all the effects of octopamine-containing neurons on the feeding network, and here we test the hypothesis that octopamine is also a neuromodulator. Results The exci...

  14. The influence of the cholesterol microenvironment in tissue sections on molecular ionization efficiencies and distributions in ToF-SIMS

    Science.gov (United States)

    Altelaar, A. F. Maarten; van Minnen, Jan; Heeren, Ron M. A.; Piersma, Sander R.

    2006-07-01

    High-resolution images of cholesterol were obtained from Lymnaea stagnalis nervous tissue using metal-assisted (MetA) time-of-flight secondary ion mass spectrometry (ToF-SIMS). The spatial distributions of different pseudomolecular ions of cholesterol [ M - H] +, [ M - OH] + and [2 M + Au] +, illustrate the influence of the tissue microenvironment on the ionization efficiencies of these ions. These biological matrix effects result in differences in localizations of molecular ions derived from the same molecular species.

  15. Observations sur le comportement trophique de jeunes saumons atlantiques dans le bassin de la Nivelle

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    VIGNES, J.C.

    1998-01-01

    Full Text Available Se ha procedido al análisis de los contenidos estomacales extraídos de pequeños salmones O+ (Salmo salar L.en un afluente de la ría Nivelle (Lapurdi. El régimen trófico está mayormente constituido por larvas de Baetide (53,7% y de Chironomidae (16,9%. La presencia de larvas de Blepharoceridae (10,6%, consumidas por el 64,2% de los peces, así como la de moluscos Ancylidae, muestra el comportamiento particular de estos salmones, capturando presas adheridas estrechamente al substrato.

  16. Estratigrafía del Cuaternario del sur de la Provincia Santa Fe, Argentina

    OpenAIRE

    Parent, Horacio; Polare, Marcelo; Lattuca, Francisco

    2010-01-01

    La clasificación estratigráfica de los sedimentos que conforman el relleno superficial de la unidad morfoestructural denominada Subcuenca Rosario ha sido revisada sobre la base de estudios actuales. Se propone la Fm. Saladillo (nov.), sección tipo en las barrancas del Río Paraná en Rosario, dentro de la cual los moluscos ocurrentes se han clasificado en cuatro conjuntos fáunicos sucesivos. Se considera que el tramo superior es de edad Holocena, mientras...

  17. Caracoles terrestres (Mollusca: Gastropoda) de Iturbide, Nuevo León, México

    OpenAIRE

    Correa Sandoval, Alfonso

    2015-01-01

    Catorce especies de caracoles terrestres son informadas del municipio de Iturbide, Nuevo León, México. El tipo de vegetación más rico en moluscos (11 especies) es el bosque de galería de Populus-Quercus-Juglans, con cobertura vegetal total y escasa pendiente. La distribución panamericana es el principal componente zoogeográfico Fourteen species of land snails are reported from the municipality of Iturbide, Nuevo León, México. The vegetation type with more species ( 1 1) is the Populus-Quer...

  18. Vibrio parahaemolyticus produtores de urease isolados a partir de ostras (Crassostrea rizophorae) coletadas in natura em restaurantes e mexilhões (Perna perna) de banco natural

    OpenAIRE

    2004-01-01

    A presença de Vibrio parahaemolyticus foi avaliada em 50 amostras de moluscos bivalves marinhos compostas por 40 amostras de ostras coletadas em 15 restaurantes do Rio de Janeiro e 10 amostras de mexilhões capturados de banco natural em Ponta de Itaipú - Niterói. Foram empregadas a técnica do Número Mais Provável (NMP) para a enumeração de V. parahaemolyticus utilizando Caldo Glicosado Salgado com Teepol (GSTB) e Água Peptonada Alcalina (APA) com 3% de cloreto de sódio (NaCl). Paralelamente f...

  19. Estado actual del aprovechamiento de subproductos de la industria pesquera mediante la obtención de productos de alto valor añadido

    OpenAIRE

    Martínez Álvarez, Óscar

    2011-01-01

    Cada año, una cantidad considerable de subproductos derivados del procesado de pescado o de moluscos son eliminados o bien transformados en comida para animales, fertilizantes, o ensilados. Este artículo ofrece una panorámica de formas tradicionales e innovadoras de valorizar tanto estos subproductos como los descartes. Estos residuos pueden ser convertidos en productos hechos a la medida del consumidor, de alto valor añadido, con prometedores aplicaciones en diversas áreas como la cosmética,...

  20. Esquistossomose: nova ocorrência de Biomphalaria straminea em Belo Horizonte, Minas Gerais Schistosomiasis: new occurrence of Biomphalaria straminea in Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1996-12-01

    Full Text Available Em Belo Horizonte, Minas Gerais, Brasil, a Biomphalaria straminea é encontrada na região da Pampulha. Recentemente, o molusco foi encontrado em valas da antiga Barragem de Santa Lúcia, foco extinto de esquistossomose transmitida por B. glabrata. Os moluscos foram coletados e examinados para verificar se estavam naturalmente infectados com Schistosoma mansoni. Os exemplares negativos foram usados para criação ou infecção com a cepa LE de S. mansoni, mantida no laboratório, e outra cepa VGS, obtida de ovos de fezes de escolar de Belo Horizonte. Dentre 1.890 moluscos capturados em 1994 e 1995, nenhum estava infectado com S. mansoni. Dentre 87 exemplares coletados no criadouro e expostos à cepa LE, nove (10,3% eliminaram cercárias; dentre 83 moluscos da F1, dez (12,0% eliminaram cercárias e dentre 88 exemplares coletados e expostos à cepa VGS, dez (11,3% eliminaram cercárias. Em Belo Horizonte, a esquistossomose é transmitida por B. glabrata e B. tenagophila. Entretanto, atualmente existe o risco de aparecimento de novo foco, no qual a B. straminea poderá vir a ser a transmissora, se medidas profiláticas adequadas não forem tomadas pelas autoridades responsáveis pela construção de um parque e lago no local.In Belo Horizonte, Minas Gerais, Brazil, the snail Biomphalaria straminea was found in the Pampulha region. Recently the snail was found in ditches in the old Santa Lúcia Reservoir, a now-extinct focus of schistosomiasis transmission by B. glabrata. The snails were collected and examined to verify whether they were naturally infected with Schistosoma mansoni. Negative specimens were used for breeding or infection with the LE strain of S. mansoni from the laboratory and another strain obtained from eggs found in the feces of a schoolchild (VGS from Belo Horizonte. Among the 1890 snails collected from 1994 to 1995, none were infected with S. mansoni. Among 87 snails collected and exposed to the LE strain, 9 (10.3% shed cercariae