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Sample records for panagrellus redivivus goodey

  1. Effect of dose-rate on the frequency of X-linked lethal mutation in the nematode Panagrellus redivivus

    International Nuclear Information System (INIS)

    Ager, D.

    1984-01-01

    A total X-ray dose of 50 Gy was applied to the nematode Panagrellus redivivus using dose-rates ranging from 0.23 Gy/min to 10.49 Gy/min, and the frequency of lethal X-chromosomes was determined. This frequency ranged from approximately 1.6% at the lower dose-rate to 4.3% at the highest dose-rate, indicating a dose-rate dependency of mutation frequency in the spermatogonia and oogonia of this organism. (orig.)

  2. Estimation of mutation rates induced by large doses of gamma, proton and neutron irradiation of the X-chromosome of the nematode Panagrellus redivivus

    International Nuclear Information System (INIS)

    Denich, K.T.R.; Samoiloff, M.R.

    1984-01-01

    The radiation-resistant free-living nematode Panagrellus redivivus was used to study mutation rates in oocytes, following gamma, proton and neutron irradiation in the dose range 45-225 grays. γ-Radiation produced approximately 0.001 lethal X-chromosomes per gray over the range tested. Proton or neutron irradiation produced approximately 0.003 lethal X-chromosomes per gray at lower doses, with the mutation rate dropping to 0.001 lethal X-chromosome per gray at the higher doses. These results suggest a dose-dependent mutation-repair system. Cell lethality was also examined. γ-Radiation produced the greatest amount of cell lethality at all doses, while neutron irradiation had no cell lethal effect at any of the doses examined. (orig.)

  3. Evaluacion de la toxicidad de Cr+6 , Cu+2 y el efluente de cromado de una industria metalmecánica utilizando panagrellus redivivus como organismo de prueba

    Directory of Open Access Journals (Sweden)

    Nahyr Murillo

    1997-09-01

    Full Text Available Los ensayos de toxicidad son procedimientos en los cuales las respuestas de ciertos organismos acuáticos son utilizadas para detectar el efecto producido por la presencia de sustancias nocivas o tóxicas. Se consideran una herramienta importante de control ambiental, puesto que permitan evaluar de una manera rápida y confiable los impactos de contaminantes tóxicos sobre los ecosistemas, así como evaluar riesgos potenciales de salud. En el presente trabajo se evaluó un bioensayo utilizando como organismo de prueba Panagrellus redivivus, nemátodo que ha mostrado una alta sensibilidad a un gran número de sustancias tóxicas. Se determinó que la CL50-96h para cromo hexavalente fue de 43 mg/l y para sulfato de cobre quelatado de 2,6 mg/l. Aunque la concentración letal, encontrada para estos elementos fue relativamente alta comparada con otros organismos acuáticos, es importante señalar que a concentraciones de 13 mg/l y 0,12 mg/l se observó un efecto significativo sobre el crecimiento y maduración de Panagrellus redivivus. Estos hechos señalaron que los metales evaluados pueden generar efectos subletales, aun a bajas concentraciones. Para el efluente evaluado se encontró que la CL50-96h fue de 1,4%, y concentraciones de 0,4 y 0,005 % producen una disminución en el crecimiento y maduración, respectivamente.

  4. Dans quelle mesure l’athéisme est-il inacceptable pour l’auteur du Theophrastus redivivus et pour Spinoza ?

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    Nicole Gengoux

    2012-09-01

    Full Text Available Un problème posé par le Theophrastus redivivus, traité anonyme achevé en 1659, matérialiste et athée (au sens actuel du terme, est que l’auteur tout en critiquant radicalement la croyance en dieu, affirme qu’il faut chasser l’athéisme de la cité. Son athéisme est pourtant « pensable » : non seulement le mot n’est pas anachronique pour le xviie siècle, comme le pensent de nombreux commentateurs, mais le traité lui-même fait la généalogie de la croyance tout en exposant un système de pensée cohérent qui se passe de dieu.Le rejet du terme « athéisme » est d’ordre moral et social car il désigne celui qui se laisse entraîner par ses instincts. L’auteur nous prévient, en quelque sorte, que ce n’est pas parce qu’il nie les dieux qu’il n’est pas respectueux des lois. Cependant, l’« inacceptabilité » du terme « athée » a aussi un sens plus profond : comment, en effet, concilier l’ordre social et l’absence d’un Bien et d’un Mal absolus ? Certes le traité propose une solution purement naturelle en fondant la morale sur l’amour de soi, mais comment le faire comprendre ? C’est peu « acceptable » au sens de « compréhensible ».Nous pouvons distinguer des degrés d’inacceptabilité : l’amoralisme théorique paraît plus inacceptable, encore, que l’affirmation de l’inexistence de dieu, parce qu’il risque d’entraîner la désobéissance civile : c’est cette dernière qui constitue l’inacceptable absolu, pour notre Anonyme comme pour les lecteurs. Une conséquence paradoxale est que la thèse de l’imposture des religions est peut-être, pour des raisons politiques, moins inacceptable que cet amoralisme et surtout que le constat par l’Anonyme de l’inefficacité totale des religions. Enfin, les choses pouvant être dites plus ou moins haut, l’acceptabilité suppose plus de complicité et d’hypocrisie de la part du lecteur que nous aurions tendance

  5. Alimento vivo como alternativa en la dieta de larvas y juveniles de Pterophyllum scalare (Lichtenstein, 1823)

    OpenAIRE

    J. Luna-Figueroa; Z. T. de J. Vargas; T. J. Figueroa

    2010-01-01

    La nutrición en los estadios iniciales de los peces constituye uno de los principales problemas de cultivo, debido a que es la etapa en la que se presenta la mayor mortalidad. En el presente estudio se evaluó, como alternativa en la alimentación de larvas y juveniles de Pterophyllum scalare, el efecto de tres alimentos vivos (Moina wierzejski, Artemia franciscana y Panagrellus redivivus) y un alimento comercial (Aquarian Tropical Flakes) sobre la tasa específica de crecimiento (TEC) y la sobr...

  6. Alimento vivo como alternativa en la dieta de larvas y juveniles de Pterophyllum scalare (Lichtenstein, 1823

    Directory of Open Access Journals (Sweden)

    J. Luna-Figueroa

    2010-01-01

    Full Text Available La nutrición en los estadios iniciales de los peces constituye uno de los principales problemas de cultivo, debido a que es la etapa en la que se presenta la mayor mortalidad. En el presente estudio se evaluó, como alternativa en la alimentación de larvas y juveniles de Pterophyllum scalare, el efecto de tres alimentos vivos (Moina wierzejski, Artemia franciscana y Panagrellus redivivus y un alimento comercial (Aquarian Tropical Flakes sobre la tasa específica de crecimiento (TEC y la sobrevivencia. La TEC de larvas resultó más alta con nauplios de A. franciscana (17.57 ± 0.39a% peso corporal ganado mg/ día, seguida de M. wierzejski (16.63 ± 0.41b, P. redivivus (14.25 ± 0.42c y del alimento comercial (13.20 ± 0.42d (P<0.05. En los juveniles, la TEC fue mayor con M. wierzejski (6.28 ± 0.21a% peso corporal ganado mg/día, seguida de A. franciscana (6.04 ± 0.23b, P. redivivus (4.86 ± 0.23c y del alimento comercial (4.39 ± 0.23d (P<0.05. La sobrevivencia de las larvas fue 80.00 ± 10.00a% con A. franciscana y M. wierzejski, mayor 25 y 40.62% con respecto a P. redivivus (60.00 ± 10.00b% y al alimento comercial (45.00 ± 10.00b% (P<0.05. En los juveniles, la sobrevivencia del 100% no difirió con ningún alimento. Finalmente, los nauplios de Artemia en la etapa larval y la Moina en juveniles estimularon favorablemente la TEC y la sobrevivencia de P. scalare.

  7. Isolation of Fungi from Heterodera glycines and in vitro Bioassays for Their Antagonism to Eggs.

    Science.gov (United States)

    Meyer, S L; Huettel, R N; Sayre, R M

    1990-10-01

    Twenty fungi were assayed in vitro for antagonism to eggs of Heterodera glycines. Eight of the fungi were isolated from cysts or eggs of H. glycines during the current study, one was isolated from Panagrellus redivivus, and eleven were obtained from other researchers or collections. The bioassays were conducted on eggs from nematodes that had been grown monoxenically on excised root tips. Phoma chrysanthemicola, one strain of Verticillium chlamydosporium, and one strain of V. lecanii caused a decrease (P Trichoderma polysporum infected live eggs but enhanced (P Fusarium sp., Neocosmospora vasinfecta, Scytalidium fulvum, Trichoderma harzianum (two strains), V. chlamydosporium (one strain), V. lecanii (three strains), and an unidentified fungus did not measurably affect egg viability, even though hyphae of five of these fungi were seen in live eggs. The bioassay provides a useful step in the selection of a biological control agent for this major nematode pest.

  8. An Enterotoxin-Like Binary Protein from Pseudomonas protegens with Potent Nematicidal Activity.

    Science.gov (United States)

    Wei, Jun-Zhi; Siehl, Daniel L; Hou, Zhenglin; Rosen, Barbara; Oral, Jarred; Taylor, Christopher G; Wu, Gusui

    2017-10-01

    Soil microbes are a major food source for free-living soil nematodes. It is known that certain soil bacteria have evolved systems to combat predation. We identified the nematode-antagonistic Pseudomonas protegens strain 15G2 from screening of microbes. Through protein purification we identified a binary protein, designated Pp-ANP, which is responsible for the nematicidal activity. This binary protein inhibits Caenorhabditis elegans growth and development by arresting larvae at the L1 stage and killing older-staged worms. The two subunits, Pp-ANP1a and Pp-ANP2a, are active when reconstituted from separate expression in Escherichia coli The binary toxin also shows strong nematicidal activity against three other free-living nematodes ( Pristionchus pacificus , Panagrellus redivivus , and Acrobeloides sp.), but we did not find any activity against insects and fungi under test conditions, indicating specificity for nematodes. Pp-ANP1a has no significant identity to any known proteins, while Pp-ANP2a shows ∼30% identity to E. coli heat-labile enterotoxin (LT) subunit A and cholera toxin (CT) subunit A. Protein modeling indicates that Pp-ANP2a is structurally similar to CT/LT and likely acts as an ADP-ribosyltransferase. Despite the similarity, Pp-ANP shows several characteristics distinct from CT/LT toxins. Our results indicate that Pp-ANP is a new enterotoxin-like binary toxin with potent and specific activity to nematodes. The potency and specificity of Pp-ANP suggest applications in controlling parasitic nematodes and open an avenue for further research on its mechanism of action and role in bacterium-nematode interaction. IMPORTANCE This study reports the discovery of a new enterotoxin-like binary protein, Pp-ANP, from a Pseudomonas protegens strain. Pp-ANP shows strong nematicidal activity against Caenorhabditis elegans larvae and older-staged worms. It also shows strong activity on other free-living nematodes ( Pristionchus pacificus , Panagrellus redivivus , and

  9. Use of various acute, sublethal and early life-stage tests to evaluate the toxicity of refinery effluents

    International Nuclear Information System (INIS)

    Sherry, J.; Scott, B.; Dutka, B.

    1997-01-01

    The toxicities of effluents from three Ontario, Canada, refineries were assessed with microbes, plants, invertebrates, and fish. Acute toxicity was assessed by the Microtox test, an assay based on electron transport activity in submitochondrial particles, and Daphnia magna (water flea); growth of Selenastrum capricornutum (alga); growth of Lemna minor (aquatic plant); germination of Lactuca sativa (nonaquatic plant); survival, growth, and maturation of Panagrellus redivivus (nematode); and genotoxicity in the SOS-Chromotest. Only the Microtox test and the submitochondrial particle test detected acute toxicity in the effluent samples. Reduced survival and sublethal responses were caused by some effluents, but not all effluents were toxic, and none caused a response in all of the tests applied. The results suggest that the effluent treatment systems used at Ontario refineries have largely eliminated acute toxicity to the organisms in their test battery. Although reduced survival and sublethal effects were detected in some of the effluents, the effects were minor. Some of the tests provided evidence, albeit weak, of variations in the responses of the test organisms to a temporal series of effluent samples. Not unexpectedly, there were also minor differences in the responses of the tests to effluents from the three refineries. The fathead minnow test seems to be a sensitive indicator of the sublethal toxicity of Ontario refinery effluents

  10. Observations on the life-cycles and larval morphogenesis of, and ...

    African Journals Online (AJOL)

    1991-06-26

    Jun 26, 1991 ... nematode-species word beskryf en hul habitat, ooreenkomste en verskille word bespreek. Skape is ..... Goodey (l951) in the potato tuber nematode Diclylenchus ... ing one with an enlarged cyst and gallbladder (Figure 6).

  11. Metodología para el diseño de bioensayos en toxicología acuática

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    Robles González Juana Raquel

    1999-12-01

    Full Text Available

    La creciente descarga de residuos industriales y domésticos, el derrame de hidrocarburos, así como de otros productos químicos ha generado serios problemas de contaminación en las aguas y, por lo tanto, es necesario usar la metodología adecuada que permita medir la naturaleza y mecanismos de los efectos de esos contaminantes sobre organismos vivientes. En este trabajo se busca: Determinar los efectos letales y subletales del endosulfan en nematodos Panagrellus redivivus; comparar los resultados mediante los métodos Probit y Logístico. Se realizaron 16 bioensayos bajo un diseño completamente al azar, para probar las concentraciones 1,6; 3,2; 6,5; 13,1 y 26 ppm de endosulfan y un control, con cinco repeticiones y 10 individuos por unidad experimental. A 96 horas, la CL50 (Concentración Letal Mediana para endosulfan fue 10,89 ppm. y las CE50 (Concentracion Efectiva Mediana de las variables supervivencia, crecimiento y maduración fueron 10,54; 0,70 Y 0,73 ppm, respectivamente.

    Palabras claves: Concentración letal, concentración efectiva, endosulfan, nematodos.

  12. Differences in the genetic control of early egg development and reproduction between C. elegans and its parthenogenetic relative D. coronatus.

    Science.gov (United States)

    Kraus, Christopher; Schiffer, Philipp H; Kagoshima, Hiroshi; Hiraki, Hideaki; Vogt, Theresa; Kroiher, Michael; Kohara, Yuji; Schierenberg, Einhard

    2017-01-01

    The free-living nematode Diploscapter coronatus is the closest known relative of Caenorhabditis elegans with parthenogenetic reproduction. It shows several developmental idiosyncracies, for example concerning the mode of reproduction, embryonic axis formation and early cleavage pattern (Lahl et al. in Int J Dev Biol 50:393-397, 2006). Our recent genome analysis (Hiraki et al. in BMC Genomics 18:478, 2017) provides a solid foundation to better understand the molecular basis of developmental idiosyncrasies in this species in an evolutionary context by comparison with selected other nematodes. Our genomic data also yielded indications for the view that D. coronatus is a product of interspecies hybridization. In a genomic comparison between D. coronatus , C. elegans , other representatives of the genus Caenorhabditis and the more distantly related Pristionchus pacificus and Panagrellus redivivus , certain genes required for central developmental processes in C. elegans like control of meiosis and establishment of embryonic polarity were found to be restricted to the genus Caenorhabditis . The mRNA content of early D. coronatus embryos was sequenced and compared with similar stages in C. elegans and Ascaris suum . We identified 350 gene families transcribed in the early embryo of D. coronatus but not in the other two nematodes. Looking at individual genes transcribed early in D. coronatus but not in C. elegans and A. suum , we found that orthologs of most of these are present in the genomes of the latter species as well, suggesting heterochronic shifts with respect to expression behavior. Considerable genomic heterozygosity and allelic divergence lend further support to the view that D. coronatus may be the result of an interspecies hybridization. Expression analysis of early acting single-copy genes yields no indication for silencing of one parental genome. Our comparative cellular and molecular studies support the view that the genus Caenorhabditis differs

  13. Differences in the genetic control of early egg development and reproduction between C. elegans and its parthenogenetic relative D. coronatus

    Directory of Open Access Journals (Sweden)

    Christopher Kraus

    2017-10-01

    Full Text Available Abstract Background The free-living nematode Diploscapter coronatus is the closest known relative of Caenorhabditis elegans with parthenogenetic reproduction. It shows several developmental idiosyncracies, for example concerning the mode of reproduction, embryonic axis formation and early cleavage pattern (Lahl et al. in Int J Dev Biol 50:393–397, 2006. Our recent genome analysis (Hiraki et al. in BMC Genomics 18:478, 2017 provides a solid foundation to better understand the molecular basis of developmental idiosyncrasies in this species in an evolutionary context by comparison with selected other nematodes. Our genomic data also yielded indications for the view that D. coronatus is a product of interspecies hybridization. Results In a genomic comparison between D. coronatus, C. elegans, other representatives of the genus Caenorhabditis and the more distantly related Pristionchus pacificus and Panagrellus redivivus, certain genes required for central developmental processes in C. elegans like control of meiosis and establishment of embryonic polarity were found to be restricted to the genus Caenorhabditis. The mRNA content of early D. coronatus embryos was sequenced and compared with similar stages in C. elegans and Ascaris suum. We identified 350 gene families transcribed in the early embryo of D. coronatus but not in the other two nematodes. Looking at individual genes transcribed early in D. coronatus but not in C. elegans and A. suum, we found that orthologs of most of these are present in the genomes of the latter species as well, suggesting heterochronic shifts with respect to expression behavior. Considerable genomic heterozygosity and allelic divergence lend further support to the view that D. coronatus may be the result of an interspecies hybridization. Expression analysis of early acting single-copy genes yields no indication for silencing of one parental genome. Conclusions Our comparative cellular and molecular studies support the

  14. Uso de productos derivados de Bacillus thuringiensis como alternativa de control en nematodos de importancia veterinaria. Revisión

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    Alejandro Vázquez-Pineda

    2012-01-01

    Full Text Available La bacteria entomopatógena Bacillus thuringiensis produce cristales proteicos con actividad citotóxica en contra de insectos y nematodos. La toxicidad de B. thuringiensis en plagas agrícolas es ampliamente conocida, pero poco se conoce acerca de su actividad en contra de nematodos parásitos. Recientemente, la actividad nematicida de las proteínas derivadas de B. thuringiensis se demostró en parásitos de mamíferos como Haemonchus, Teladorsagia, Nippostrongylus, y Ancylostoma, y en nematodos de plantas, Globodera y Meloidogyne. Entre el grupo de B. thuringiensis con efecto nematicida, las proteínas de la cepa IB-16 han mostrado actividad letal de 50 a 100 % en contra de diferentes estadios del principal género de rumiantes, Haemonchus contortus. Asimismo, los géneros de nematodos de vida libre, Panagrellus redivivus y Caenorhabditis elegans han sido blanco de estudios de la acción nematicida de B. thuringiensis. Por ejemplo, el efecto tóxico de la proteína Cry5B de B. thuringiensis se observó en las células intestinales de C. elegans, además esta acción parece involucrar receptores celulares específicos, similares a los que se han notificado en contra de plagas agrícolas. Asimismo, la unión de la proteína Cry5B ocurre en receptores específicos, como moléculas de carbohidratos, las cuales están presentes en la membrana de las células de intestino de los nematodos, ocasionando daño y muerte. A través de este tipo de estudios, los derivados de B. thuringiensis podrían considerarse una alternativa de control en nematodos que afectan a los animales domésticos, como rumiantes, así como en contra de otros nematodos patógenos de mamíferos e incluso de plantas agrícolas.

  15. Tetracyclic indole alkaloids with antinematode activity from Uncaria rhynchophylla.

    Science.gov (United States)

    Kong, Fandong; Ma, Qingyun; Huang, Shengzhuo; Yang, Shuang; Fu, Linran; Zhou, Liman; Dai, Haofu; Yu, Zhifang; Zhao, Youxing

    2017-06-01

    A new tetracyclic indole alkaloid, 17-O-methyl-3,4,5,6-tetradehydrogeissoschizine, together with seven known ones, were isolated from the aerial part of Uncaria rhynchophylla. Their structures were unambiguously elucidated by spectroscopic methods and comparing with the literature data. Among them, compounds 1, 3, 4 and 6-8 showed potent to moderate antinematode activities against Panagrellus redivevus at a concentration of 250 μg/mL.

  16. Estudio del paradigma mesiánico de Elías: Historia de su interpretación

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    P. César Carbullanca N

    2006-12-01

    Full Text Available La expectativa mesiánica del profeta escatológico se presenta en las Sagradas Escrituras por medio de los textos Dt 18, 18; Ex 23, 20 y Mal 3, 1. 23, que hablan de las figuras de Moisés y Elías. Este artículo, el primero de una serie, está centrado solo en Elías y presenta la historia de la interpretación que han realizado en torno a la figura del profeta durante el periodo que media entre el judaísmo tardío y el cristianismo primitivo. El artículo explica en primer lugar los antecedentes conceptuales y terminológicos de esta expectativa; en segundo lugar expone las diversas connotaciones que posee la figura de Elías durante el judaísmo tardío, tanto en Qumrán como en la literatura rabínica. En tercer lugar desarrolla la interpretación que realizaron distintas comunidades cristianas de la venida del Elías redivivus, representadas por los textos de Lc 1, 68-79; Lc 7, 26-29 y Mc 9, 11-13. Esta historia de la interpretación otorga una "panorámica" que contextualiza adecuadamente las diversas confesiones cristológicas en los textos neotestamentariosThe messianic expectation of the eschatological prophet is presented in Sacred Scripture in the following texts: Dt 18:18, Ex 23:20 and Mal 3: 1, 23, which speak of the figures of Moses and Elijah. This article, the first in a series, is centered solely upon Elijah and presents the history of the interpretation that has been done regarding the figure of this prophet during the period that extends from late Judaism to primitive Christianity. The article explains, in the first place, the conceptual and terminological backgrounds of this expectation. In the second place, it expounds upon the diverse connotations that the figure of Elijah possessed during late Judaism, as much in Qumran as in rabbinical literature. Thirdly, it develops the interpretation that distinct Christian communities made about the coming of Elijah redivivus, represented by the texts Lk 1: 68-79; 7: 26-29 and Mk 9

  17. Scanning electron microscopy of the predatory ability of agents of the biocontrol of nematodes/ Microscopia eletrônica de varredura da habilidade predatória de agentes do biocontrole de nematóides

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    João Carlos de Oliveira

    2001-08-01

    Full Text Available Nematode-trapping fungi have been studied as a promising alternative to control bovine gastrointestinal parasites and plant parasitic nematodes. Some encouraging results have been achieved with some species, by many researchers. Nematophagous fungi such as Arthrobotrys javanica, Dactylella leptospora, Monacrosporium eudermatum, M. robustum e Nematoctonus campylosporus were isolated from soil samples collected from different crops and agronomic environments proceeding from varies places in Brazil, making use of soil spreading methods. These fungi species were isolated at the Center of Animal Parasitology (CPPAR at UNESP/FCAV, Campus Jaboticabal – SP. The predatory ability of these fungi, on free living nematodes (Panagrellus sp. was documented at the Scanning Electron Microscopy Lab. The objectives of this work were to document, through Scanning Electron Microscopy (SEM, the morphological structures of these fungi, such as: capturing structures, size, form, septation of the conidia, connection clamp, exclusively on N. campylosporus, as well as the free-living nematodes captured by these fungi.Fungos nematófagos têm sido estudados como uma alternativa promissora para o manejo de nematóides de plantas e parasitos gastrintestinais de bovinos. Resultados encorajadores têm sido obtidos com algumas espécies, por vários pesquisadores. A partir de amostras de solo coletadas em diferentes culturas e agroecossistemas provenientes de diversas localidades do Brasil, foram isolados, pelo método de espalhamento de solo, os fungos nematófagos Arthrobotrys javanica, Dactylella leptospora, Monacrosporium eudermatum, M. robustum e Nematoctonus campylosporus, no Centro de Pesquisas em Sanidade Animal (CPPAR da UNESP/FCAV, Câmpus de Jaboticabal - SP, e a habilidade predatória destes fungos sobre o nematóide de vida livre Panagrellus sp. foi estudada no Laboratório de Microscopia Eletrônica de Varredura. Este trabalho teve como objetivo documentar ao

  18. Lack of negative effects of the biological control agent Duddingtonia flagrans on soil nematodes and other nematophagous fungi.

    Science.gov (United States)

    Saumell, C A; Fernández, A S; Echevarria, F; Gonçalves, I; Iglesias, L; Sagües, M F; Rodríguez, E M

    2016-11-01

    The possible environmental effects of the massive use of Duddingtonia flagrans for controlling sheep nematodes were evaluated in two regions. Non-supplemented faeces and faeces from sheep supplemented with D. flagrans were deposited three times on pasture plots and samples were collected 7 and 14 days post-deposition. Samples were cultured in agar-water (2%) with Panagrellus spp. to recover D. flagrans and other nematophagous fungi, and soil nematodes were extracted using Baermann funnels and counted. No significant differences in the populations of soil nematodes and fungi colonizing sheep faeces (P > 0.05) were observed between supplemented and non-supplemented groups, except in one sample. The topsoil in contact with the faeces was sampled 1-4 months post-deposition, revealing that, with one exception, D. flagrans did not persist in soil beyond 2 months post-deposition. Duddingtonia flagrans does not affect faecal colonization by other fungi and soil nematodes and, once deployed on pasture, does not survive for long periods in the environment.

  19. Nematophagous fungi from decomposing cattle faeces in Argentina.

    Science.gov (United States)

    Saumell, Carlos Alfredo; Fernández, Alicia Silvina; Fusé, Luis Alberto; Rodríguez, Manuela; Sagüés, María Federica; Iglesias, Lucía Emilia

    2015-01-01

    Biological control of gastrointestinal nematodes of ruminants by use of nematophagous fungi would become part of any livestock parasite integral control system. Identifying autochthonous species that could then be selected for mass production is an important phase in the practical use of biological control. To search for nematophagous fungi with potential use as biological control agents against gastrointestinal nematodes in Argentina. Decomposing cattle faeces sampled in different locations were incubated in water agar 2% with Panagrellus sp. The developed nematophagous fungi were transferred to new water agar 2% plates and then to corn meal agar plates in order to carry out their identification. Fungal diversity and richness were also assessed. Seventeen species from nine genera of nematophagous fungi were found. Twelve species were nematode-trapping fungi and three species plus two fungi identified to genus level corresponded to endoparasitic fungi. Arthrobotrys conoides, Arthrobotrys oligospora, Duddingtonia flagrans, Monacrosporium doedycoides, Arthrobotrys robusta and Drechmeria coniospora were the most frequently isolated species overall in the whole study (6.6%, 5.7%, 5.7%, 5.7%, 4.7% and 4.7%, respectively) although other species were more frequently recorded at local levels such as Arthrobotrys pyriformis (18.8%). Only A. conoides has been previously isolated from ruminant faecal samples in Argentina. Five nematode-trapping fungal species are mentioned for the first time in the Americas D. flagrans and A. conoides, both identified in the present study, are among the most promising ones as biological control agents against gastrointestinal nematodes of ruminants. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  20. Different foods in larvicultura of traíra (Hoplias malabaricus

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    Samuel Louzada Pereira

    2015-10-01

    Full Text Available ABSTRACT. Pereira S.L., Mendonça P.P., Pellanda A.S., Matielo M.D. & Gon- çalves Junior L.P. [Different foods in larvicultura of traíra (Hoplias malabaricus.] Utilização de diferentes alimentos na larvicultura de traíra (Hoplias malabaricus. Revista Brasileira de Medicina Veterinária, 37(3:233-238, 2015. Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego, 2000, Parque Califórnia, Campos dos Goytacazes, RJ 28013-602, Brasil. E-mail: samuell_lp@hotmail.com The feeding in the larviculture of species carnivorous view point for closing of the technological packages of rearing culture. Developed in the sector of Aquicultura of the IFES - Campus of Alegre, this work it aimed at to compare the performance with four diet feed as first exogenous feeding for traíra (Hoplias malabaricus, parameters evaluated: Survival, length final (CF, final weight (PF, tax of specific growth (TCE, development tax specifies (TDE, being put in container with fifteen liters of water, with constant aeration, have five larva of traíra/container. The delineation entire was aleatory with four treatments and five repetitions. Being the diet feeds represented for T1: Nauplios de Artemia sp.; T2: microworm of oats (Pannagrelos redivivus; T3: Wild Zooplâncton; e the inert food represented by T4: Commercial ration in dust with 55% of crude protein and 4,200 Kcal de ED/kg of ration. The water exchange was of 80% daily, the average temperature was of 27.5±1°C. The indices of survival in the T1, T2, T3 and T4, had been 84%, 72%, 100% and 92%, respectively. The date had been submitted analyze it statistics ANOVA and test of Tukey (P<0.01. Wild Zooplâncton was biggest CTF, PF, GP, TCE and TDE. Did not have difference statistics between the Artemia sp. the ration for TCE and TDE. The microworm of oats was minor CF, PF, TCE and TDE. The treatment Wild zooplankton (T3 showed optimum diet food among the other diet feeds tested for the development and

  1. Architectural layout and vulnerability to earthquakes of housing buildings of the Modernism

    Science.gov (United States)

    Bostenaru, M.

    2009-04-01

    seismic culture developed. The buildings of Greek Modernism and those of the Milanese Novecento however, are more regular in shape and in the distribution of columns and beams. It will be investigated if this is a consequence of the local seismic culture or if it was simply allowed by the regular shape of the lots in the urban tissue. Buildings of Greek Modernism were raised, unlike those in Bucharest, in more peripheral zones of the city, mainly in the neighbourship of the train station. In Bucharest they were raised in the city centre, following a major urban redevelopment. The buildings of Milanese Novecento, however, are spread over the whole city and here it is more difficult to find a reason in the argumentative discourse. It will be looked at the vernacular types of the houses in the country. The Modernist buildings were raised in a time when no seismic codes yet were released. All of the mentioned building types have a reinforced concrete skeleton. When conducting studies about historical buildings, mainly those with masonry structure are considered, for which reason the project CA'REDIVIVUS was run 2005-2007, with support from the European Commission, aiming exactly at this: the preservation of historic housing buildings with reinforced concrete structure across Europe. This research aims to continue that research, considering buildings from the same geographical locations but from the point of view of the way of living which led to the architectural shape which rendered vulnerable or not these buildings. It is an argumentative discourse to be conducted about to which amount the Modernism negated the historical links and thus also the vernacular one. Sure is, that at least on Romania, there had to be a change in living habits to move from single family to multi-family building. These buildings were also not typical for Modernism in Europe, since they were thought for luxus dwellings in the city centre. In Western Europe it was social housing at the periphery

  2. Applicability and economic efficiency of earthquake retrofit measures on existing buildings in Bucharest, Romania

    Science.gov (United States)

    Bostenaru, M.

    2009-04-01

    Research Training Network 450 "Natural Disasters" supported by the DFG (German Research Network), 2000-2004 while the result was published with support from a subsequent research project of the author, CA'REDIVIVUS, which continued the research, supported by the European Commission, in 2006.