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Sample records for chironomus plumosus larvae

  1. CHIRONOMUS PLUMOSUS LARVAE - A SUITABLE NUTRIENT FOR FRESHWATER FARMED FISH

    OpenAIRE

    Valentina Rajković; Zdeněk Adámek; Elizabeta Has-Schön; Ivan Bogut; Dalida Galović

    2007-01-01

    Crude protein, fat, water, ash, dry matter and essential amino and fatty acids were analyzed from freshly collected Chironomus plumosus larvae in order to evaluate their suitability as a component for farmed fish diet. The analyses were performed in intact living organisms and in the dry matter. Essential amino acidswere determined by LKB 4101 automatic analyzer, while fatty acids were determined by Chronopack CP 9000 chromatograph with flame ionization detector. Crude protein content was...

  2. CHIRONOMUS PLUMOSUS LARVAE - A SUITABLE NUTRIENT FOR FRESHWATER FARMED FISH

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    I. Bogut

    2007-06-01

    Full Text Available Crude protein, fat, water, ash, dry matter and essential amino and fatty acids were analyzed from freshly collected Chironomus plumosus larvae in order to evaluate their suitability as a component for farmed fish diet. The analyses were performed in intact living organisms and in the dry matter. Essential amino acids were determined by LKB 4101 automatic analyzer, while fatty acids were determined by Chronopack CP 9000 chromatograph with flame ionization detector. Crude protein content was 7.6% and 55.7% in fresh larvae and dry matter, respectively, being a value adequate for growth needs of all freshwater fish sorts and categories. Most essential amino acids in fresh larvae and dry matter are present in quantities adequate for feeding majority of omnivorous and carnivorous freshwater fish species. Crude fat content was 1.3% and 9.7% in fresh larvae and dry matter, respectively, being energetically sufficient for all warm-water living fish. The crude fat contains 26.12% saturated, 30.42% monounsaturated and 34.03% polyunsaturated fatty acids (PUFA. Among the highly unsaturated fatty acids (HUFA, the most abundant is linolenic (7.21%, followed by eicosapentanoic (4.36%, docosahexaenoic (2.49% and docosapentaenoic (1.16% acid. The measured quantity of ω-3 and ω-6 fatty acids (essential for omnivorous fish, as well as ω-6 to ω-3 fatty acid ratio (0.81, completely meets nutritional requirements of carp and tench.

  3. Chironomus plumosus larvae increase fluxes of denitrification products and diversity of nitrate-reducing bacteria in freshwater sediment

    DEFF Research Database (Denmark)

    Poulsen, Morten; W. V. Kofoed, Michael; H. Larsen, Lone;

    2014-01-01

    Benthic invertebrates affect microbial processes and communities in freshwater sediment by enhancing sediment-water solute fluxes and by grazing on bacteria. Using microcosms, the effects of larvae of thewidespread midge Chironomus plumosus on the efflux of denitrification products (N2O and N2+ N2O......) and the diversity and abundance of nitrate- and nitrous-oxide-reducing bacteria were investigated. Additionally, the diversity of actively nitrate- and nitrous-oxide-reducing bacteria was analyzed in the larval gut.The presence of larvae increased the total effluxes of N2O and N2+N2O up to 8.6- and 4...... neither narG, nor nosZ wasdifferent in sediments with and without larvae. Hence, C. plumosus increases activity and diversity, but not overall abundance of nitrate-reducing bacteria, probably by providing additional ecological niches in its burrow and gut....

  4. Contrasting effects of black carbon amendments on PAH bioaccumulation by Chironomus plumosus larvae in two distinct sediments: Role of water absorption and particle ingestion

    International Nuclear Information System (INIS)

    Two sediment matrices with different characteristics were amended with chars from different sources for bioaccumulation assay with filter-feeding Chironomus plumosus larvae. Chars greatly decreased porewater concentrations of PAHs (Ciw) measured using polyethylene devices in sediments. In organic rich sediment matrix-based systems where suspended char particles were absent, PAH concentrations in larvae (CiB) were significantly correlated with Ciw, and there was no difference in water-based bioaccumulation factors (BAFs) between different treatments, suggesting that water absorption was the main contaminant uptake route for larvae. In organic poor sediment matrix-based systems where suspended char particles were present, poor Pearson correlation between CiB and Ciw was found, but there was a significant linear increase of BAF values with char contents, which indicated that ingestion of suspended char particles could also be important for PAH bioaccumulation. Therefore, we need to rethink of the effectiveness and risks for the application of black carbon to sediment/soil remediation. - Highlights: → Chars greatly decreased PAH porewater concentrations. → Without char suspension, PAH bioaccumulation depended on porewater concentrations. → With char suspension, ingestion could also be important for PAH bioaccumulation. - Contrasting effects of chars on PAH bioaccumulation by Chironomus plumosus larvae in two distinct sediments were attributed to the shift of main biouptake routes.

  5. The influence of gamma-radiation to effectiveness of conjugation of polytene chromosome of Chironomus plumosus L

    International Nuclear Information System (INIS)

    Chironomus plumosus L. from nature pond of the Brest region were used for experiments. Larvae were irradiated in doses 1, 10, 100 Gy and after 15 days checked for frequency of chromosomal disorder. On examination, gamma-radiation decreases effectiveness of conjugation of polytene chromosome of Chironomus plumosus L. This effect amplifies if increase dose of radiation

  6. Control of nitrous oxide emission from Chironomus plumosus larvae by nitrate and temperatur

    DEFF Research Database (Denmark)

    Stief, Peter; Polerecky, Lubos; Poulsen, Morten;

    2010-01-01

    Aquatic invertebrates that ingest large numbers of bacteria produce substantial amounts of the greenhouse gas N2O because of incomplete denitrification in their anoxic gut. We investigated the influence of two key environmental factors, temperature and NO3- availability, on N2O emission from larvae...... ind.-1 h-1, and N2O uptake was never observed. For both types of larvae, the rate of N2O emission was stimulated by temperature (when the NO3- concentration in the water column was higher than 25–50 µmol L-1) and by NO3- (when the temperature was higher than 4–10°C). Modeling based on experimentally...

  7. Decaying cyanobacteria decrease N2O emissions related to diversity of intestinal denitrifiers of Chironomus plumosus

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    Xu Sun

    2014-10-01

    Full Text Available Nitrous oxide (N2O emission of fresh invertebrates has too long been neglected in eutrophic lakes, although the sediments these animals inhabit are presumably hot spots of N2O emission. Thus, the experiment in this research was designed to gain insight into the influence of cyanobacterial degradation on the N2O emission by fresh water invertebrates (Chironomus plumosus. The presence of decaying cyanobacteria in Lake Taihu decreased the N2O emission rate of Chironomus plumosus larvae from the larvae body by almost 400% for the larvae as a whole. The N2O emission rate decreased by 350% based on readings from studies of their gut, which was mostly due to stimulation of intestinal complete denitrification. The quantitative PCR results showed that intestinal gene abundance of nirK, nosZ (encoding the copper nitrite reductase and N2O reductase, respectively were significantly increased with the presence of decaying cyanobacteria. In contrast nirS (encoding the cytochrome cd1 heme nitrite reductase and the total bacteria decreased. In the gut of Chironomus plumosus, the diversity and richness of nosZ and nirK were lower with the cyanobacteria. Phylogenetic analysis of the intestinal function genes (nosZ and nirK showed that the nosZ- and nirK-type denitrifying bacterial sequences were related to different phylotypes. Hence, additional cyanobacteria increased the abundance, but decreased the richness and diversity of intestinal nitrate-reducing bacteria, probably by providing more carbon source in the gut. The data obtained in this study elucidates that the decaying cyanobacteria decreased the emissions of N2O by the aquatic invertebrates in freshwater sediment and could serve as a valuable resource for nitrogen removal affecting greenhouse gas emissions.

  8. Chironomus plumosus' påvirkning af næringsstofflukse i restaurerede søer

    DEFF Research Database (Denmark)

    Kristensen, Thomas Boll; Reitzel, Kasper; Andersen, Frede Østergaard;

    Den interne næringsstofbelastning af en række danske søer har betydet at disse søer er forblevet i en uklar, algedomineret tilstand til trods for reduktioner i mængden af tilførte næringsstoffer. I mange tilfælde er der derfor efterfølgende lavet et eller flere restaureringsindgreb for at skabe e....... plumosus efter længere tid vil øge bindingen af fosfor.   Andersen,F.Ø.; Jørgensen,M.; Jensen, H.S. (2006). The influence of Chironomus plumosus larvae on nutrient fluxes and phosphorus fractions in aluminum treated lake sediment. Water, Air, and Soil Pollution: Focus....

  9. Toxicity of cadmium and lead on tropical midge larvae, Chironomus kiiensis Tokunaga and Chironomus javanus Kieffer (Diptera:Chironomidae)

    Institute of Scientific and Technical Information of China (English)

    Warrin Ebau; Che Salmah Md Rawi; Zubir Din; Salman Abdo Al-Shami

    2012-01-01

    Objective: To investigate the acute toxicity of cadmium and lead on larvae of two tropical Chironomid species, Chironomus kiiensis (C. kiiensis) Tokunaga and Chironomus javanus (C. javanus) Kieffer. Methods: Different larval instars (first-fourth) were exposed using a static non-replacement testing procedures to various concentrations of cadmium and lead. Results:In general, younger larvae (first and second instars) of both species were more sensitive to both metals than older larvae (third and forth instars). The toxic effects of the metals on C. kiiensis and C. javanus were influenced by the age of the larvae (first to fourth instars), types of metals (cadmium or lead) and duration of larval exposure (24, 48, 72 and 96 h) to the metals. Conclusions: Cadmium was more toxic to the chironomids than lead and C. javanus was significantly more sensitive to both metals than C. kiiensis (P<0.05).

  10. Bioaccumulation of perfluoroalkyl compounds in midge (Chironomus riparius) larvae exposed to sediment

    International Nuclear Information System (INIS)

    Midge larvae (Chironomus riparius) were exposed to sediments from a deposition sampled at a site along the Rhône River (France) downstream of an industrial site releasing various perfluorinated chemicals. This sediment is characterized by high concentrations of perfluoroundecanoic acid (PFUnA) and perfluorotridecanoic acid (PFTrDA) and a low perfluorooctane sulfonate (PFOS) concentration. Concentrations of 23 perfluoroalkyl compounds, including C4–C14 carboxylate acids, C4–C10 sulfonates, and seven precursors, were analyzed in overlying and pore water, sediment, and larvae. Midge larvae accumulated carboxylate acids (C11–C14), PFOS, and two precursors (perfluorooctane sulfonamide: FOSA and 6:2 fluorotelomer sulfonic acid, 6:2 FTSA). These substances accumulated mainly during the fourth instar larvae exponential growth phase. Accumulation of 6:2 FTSA, PFUnA, and PFOS occured via trophic and tegumentary routes. Other compounds mainly accumulated from food. Kinetics followed a partition model, from which uptake and elimination constants were derived. - Highlights: • Chironomus riparius were exposed to natural sediment from Rhône River (France). • Sediment contained high concentrations of PFUnA and PFTrDA and little PFOS. • C. riparius accumulated carboxylate acids (C11–C14), PFOS, FOSA and 6:2 FTSA. • Accumulation occurs mainly in growth phase at fourth instar larvae. • Accumulation routes were tegumentary and/or trophic depending on compounds. - Chironomus riparius mainly bioaccumulates long-chain PFASs via trophic and/or tegumentary routes during the fourth instar larvae growth phase

  11. Chironomus larvae (Chironomidae: Diptera) as water quality indicators along an environmental gradient in a neotropical urban stream

    OpenAIRE

    Nadja Gomes Machado; Danielle Christine Stenner Nassarden; Francyele dos Santos; Isabelle Christina Gonçalves Boaventura; Gregory Perrier; Fernanda Silveira Carvalho de Souza; Eucarlos de Lima Martins; Marcelo Sacardi Biudes

    2015-01-01

    Anthropogenic interference in urban lotic systems is a factor affecting the biota of waterbodies. Aquatic macro invertebrates are an important food source for fish and are valuable indicators of water quality. The objective of this work was to study Chironomus larvae (Chironomidae: Diptera) distribution along an environmental gradient in Barbado Stream, Cuiabá, MT, Brazil. No individual Chironomus was found in the springs of Barbado Stream, which may indicate preservation of the area. During ...

  12. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    International Nuclear Information System (INIS)

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O3/L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O3/L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O3/L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  13. A Determination of Metallothionein in Larvae of Freshwater Midges (Chironomus riparius Using Brdicka Reaction

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    Rene Kizek

    2008-07-01

    Full Text Available Among wide spectrum of biomolecules induced by various stress factors low molecular mass protein called metallothionein (MT is suitable for assessment of the heavy metal environmental pollution. The aim of this work was to determine the metallothionein and total thiols content in larvae of freshwater midges (Chironomus riparius sampled from laboratory exposure to cadmium(II ions and from field studies using differential pulse voltammetry Brdicka reaction. Unique electrochemical instrument, stationary electrochemical analyser Autolab coupled with autosampler, was utilized for the analysis of the samples. The detection limit for MT was evaluated as 5 nM. The larvae exposed to two doses (50 ng/g or 50 μg/g of cadmium(II ions for fifteen days under laboratory controlled conditions were at the end of the exposure killed, homogenized and analysed. MT content in control samples was 1.2 μM, in larvae exposed to 50 ng Cd/g it was 2.0 μM and in larvae exposed to 50 μg Cd/g 2.9 μM. Moreover at field study chironomid larvae as well as sediment samples have been collected from eight field sites with different levels of pollution by heavy. The metals content (chromium, nickel, copper, zinc, arsenic, molybdenum, cadmium, tin and lead in the sediment and or MT content in the chironomid larvae were determined by inductively coupled plasma mass spectrometry or Brdicka reaction, respectively.

  14. Chironomus larvae (Chironomidae: Diptera as water quality indicators along an environmental gradient in a neotropical urban stream

    Directory of Open Access Journals (Sweden)

    Nadja Gomes Machado

    2015-04-01

    Full Text Available Anthropogenic interference in urban lotic systems is a factor affecting the biota of waterbodies. Aquatic macro invertebrates are an important food source for fish and are valuable indicators of water quality. The objective of this work was to study Chironomus larvae (Chironomidae: Diptera distribution along an environmental gradient in Barbado Stream, Cuiabá, MT, Brazil. No individual Chironomus was found in the springs of Barbado Stream, which may indicate preservation of the area. During the study period, we found 40.3 and 94.4 individuals/m2 at points 3 and 4 (low course, respectively. There is eutrophication in these sites due to domestic sewage discharges, indicating low quality water. The Barbado Stream needs restoration projects that include an awareness of the residents of their neighborhood’s environmental importance, and investments in the sanitation sector to prioritize the collection and treatment of wastewater and solid waste collection.

  15. UV filters induce transcriptional changes of different hormonal receptors in Chironomus riparius embryos and larvae.

    Science.gov (United States)

    Ozáez, Irene; Aquilino, Mónica; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2016-07-01

    Organic ultraviolet (UV) filters are emerging contaminants that are ubiquitous in fresh and marine aquatic systems due to their extensive use in cosmetics, plastics, paints, textiles, and many other industrial products. The estrogenic effects of organic UV filters have been long demonstrated in vertebrates, and other hormonal activities may be altered, according to more recent reports. The impact of UV filters on the endocrine system of invertebrates is largely unknown. We have previously reported that some UV filters may affect ecdysone-related genes in the aquatic insect Chironomus riparius, an ecotoxicologically important model organism. To further analyze other possible effects on endocrine pathways, we first characterized four pivotal genes related with hormonal pathways in insects; thereafter, these genes were assessed for alterations in transcriptional activity after exposure to 4-methylbenzylidene camphor (4MBC) or benzophenone-3 (BP-3), two extensively used sunscreens. We found that both chemicals disturbed the expression of all four genes analyzed: hormonal receptor 38 (HR38), methoprene-tolerant (Met), membrane-associate progesterone receptor (MAPR) and insulin-like receptor (INSR), measured by changes in mRNA levels by real-time PCR. An upregulatory effect at the genomic level was detected in different developmental stages. Interestingly, embryos appeared to be more sensitive to the action of the UV filters than larvae. Our results suggest that the risk of disruption through different endocrine routes is not negligible, considering the significant effects of UV filters on key hormonal receptor and regulatory genes. Further effort is needed to develop environmental risk assessment studies on these pollutants, particularly for aquatic invertebrate model organisms. PMID:27089421

  16. A novel computational approach of image analysis to quantify behavioural response to heat shock in Chironomus Ramosus larvae (Diptera: Chironomidae

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    Bimalendu B. Nath

    2015-07-01

    Full Text Available All living cells respond to temperature stress through coordinated cellular, biochemical and molecular events known as “heat shock response” and its genetic basis has been found to be evolutionarily conserved. Despite marked advances in stress research, this ubiquitous heat shock response has never been analysed quantitatively at the whole organismal level using behavioural correlates. We have investigated behavioural response to heat shock in a tropical midge Chironomus ramosus Chaudhuri, Das and Sublette. The filter-feeding aquatic Chironomus larvae exhibit characteristic undulatory movement. This innate pattern of movement was taken as a behavioural parameter in the present study. We have developed a novel computer-aided image analysis tool “Chiro” for the quantification of behavioural responses to heat shock. Behavioural responses were quantified by recording the number of undulations performed by each larva per unit time at a given ambient temperature. Quantitative analysis of undulation frequency was carried out and this innate behavioural pattern was found to be modulated as a function of ambient temperature. Midge larvae are known to be bioindicators of aquatic environments. Therefore, the “Chiro” technique can be tested using other potential biomonitoring organisms obtained from natural aquatic habitats using undulatory motion as a behavioural parameter.

  17. Ribosomal genes as early targets of cadmium-induced toxicity in Chironomus riparius larvae

    International Nuclear Information System (INIS)

    Cadmium is a widespread environmental pollutant that causes severe impacts in organisms. Although the effects of cadmium on aquatic insects have been studied in terms of their toxicity and changes in developmental parameters, little is known about its molecular and genetic effects. We have investigated the alterations in the pattern of gene expression provoked by acute exposure to cadmium in Chironomus riparius Mg. (Diptera, Chironomidae), a sentinel organism widely used in aquatic toxicity testing. The early cytotoxic effects were evaluated using immunocytochemistry and specific fluorescent probes in fourth instar larvae after 12 h of 10 mM cadmium treatments; under these conditions no significant effect on larvae mortality was detected until after 36 h of exposure. The changes in the pattern of gene expression were analysed by means of DNA/RNA hybrid antibodies in the polytene chromosomes from salivary gland cells. A decrease in the activity of the nucleolus is especially remarkable, accompanied by a significant reduction in size and the modification in nucleolar architecture, as shown by FISH. The inhibition of rDNA transcription was further evaluated by Northern blot analysis, which showed a marked decrease in the level of preribosomal rRNA (54% 45S 12 h). However, the BR genes, whose products are the giant polypeptides that constitute the silk-like secretion for constructing housing tubes, remain active. Simultaneously, decondensation and activation take place at some chromosomal regions, especially at the centromeres. The changes observed in the pattern of gene expression do not resemble those found after heat shock or other cell stressors. These data provide the first evidence that cadmium interacts with ribosomal genes and results in a drastic impairment of the functional activity of the nucleolus, an essential organelle for cellular survival. Therefore, the depletion of ribosomes would be a long-term effect of Cd-induced cellular damage. These findings may

  18. Ribosomal genes as early targets of cadmium-induced toxicity in Chironomus riparius larvae

    Energy Technology Data Exchange (ETDEWEB)

    Planello, R. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain); Martinez-Guitarte, J.L. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain); Morcillo, G. [Biologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28040, Madrid (Spain)]. E-mail: gmorcillo@ccia.uned.es

    2007-02-01

    Cadmium is a widespread environmental pollutant that causes severe impacts in organisms. Although the effects of cadmium on aquatic insects have been studied in terms of their toxicity and changes in developmental parameters, little is known about its molecular and genetic effects. We have investigated the alterations in the pattern of gene expression provoked by acute exposure to cadmium in Chironomus riparius Mg. (Diptera, Chironomidae), a sentinel organism widely used in aquatic toxicity testing. The early cytotoxic effects were evaluated using immunocytochemistry and specific fluorescent probes in fourth instar larvae after 12 h of 10 mM cadmium treatments; under these conditions no significant effect on larvae mortality was detected until after 36 h of exposure. The changes in the pattern of gene expression were analysed by means of DNA/RNA hybrid antibodies in the polytene chromosomes from salivary gland cells. A decrease in the activity of the nucleolus is especially remarkable, accompanied by a significant reduction in size and the modification in nucleolar architecture, as shown by FISH. The inhibition of rDNA transcription was further evaluated by Northern blot analysis, which showed a marked decrease in the level of preribosomal rRNA (54% 45S 12 h). However, the BR genes, whose products are the giant polypeptides that constitute the silk-like secretion for constructing housing tubes, remain active. Simultaneously, decondensation and activation take place at some chromosomal regions, especially at the centromeres. The changes observed in the pattern of gene expression do not resemble those found after heat shock or other cell stressors. These data provide the first evidence that cadmium interacts with ribosomal genes and results in a drastic impairment of the functional activity of the nucleolus, an essential organelle for cellular survival. Therefore, the depletion of ribosomes would be a long-term effect of Cd-induced cellular damage. These findings may

  19. Ultraviolet filters differentially impact the expression of key endocrine and stress genes in embryos and larvae of Chironomus riparius.

    Science.gov (United States)

    Ozáez, Irene; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2016-07-01

    Several organic UV filters have hormonal activity in vertebrates, as demonstrated in fishes, rodents and human cells. Despite the accumulation of filter contaminants in aquatic systems, research on their effects on the endocrine systems of freshwaters invertebrates is scarce. In this work, the effects of five frequently used UV filters were investigated in embryos and larvae of Chironomus riparius, which is a reference organism in ecotoxicology. LC50 values for larvae as well as the percentage of eclosion of eggs were determined following exposures to: octyl-p-methoxycinnamate (OMC) also known as 2-ethylhexyl-4-methoxycinnamate (EHMC); 4-methylbenzylidene camphor (4MBC); 4-hydroxybenzophenone (4HB); octocrylene (OC); and octyldimethyl-p-aminobenzoate (OD-PABA). To assess sublethal effects, expression levels of the genes coding for the ecdysone receptor (EcR) and heat shock protein HSP70 were investigated as biomarkers for endocrine and stress effects at the cellular level. Life-stage-dependent sensitivity was found. In embryos, all of the UV filters provoked a significant overexpression of EcR at 24h after exposure. OC, 4MBC and OD-PABA also triggered transcriptional activation of the hsp70 stress gene in embryos. In contrast, in larvae, only 4MBC and OMC/EHMC increased EcR and hsp70 mRNA levels and OD-PABA upregulated only the EcR gene. These results revealed that embryos are particularly sensitive to UV filters, which affect endocrine regulation during development. Most UV filters also triggered the cellular stress response, and thus exhibit proteotoxic effects. The differences observed between embryos and larvae and the higher sensitivity of embryos highlight the importance of considering different life stages when evaluating the environmental risks of pollutants, particularly when analyzing endocrine effects. PMID:26994811

  20. Evaluation of mentum deformities of Chironomus spp. (Chironomidae: Diptera) larvae using modified toxic score index (MTSI) to assess the environmental stress in Juru River Basin, Penang, Malaysia.

    Science.gov (United States)

    Al-Shami, Salman Abdo; Salmah, Mad Rawi Che; Hassan, Ahmad Abu; Azizah, Mohd Nor Siti

    2011-06-01

    Morphological mentum deformities which represent sublethal effect of exposure to different types of pollutants were evaluated in Chironomus spp. larvae inhabiting three polluted rivers of Juru River Basin in northwestern peninsular Malaysia. Using mentum deformity incidences, the modified toxic score index (MTSI) was developed based on Lenat's toxic score index (TSI). The suggested MTSI was compared with TSI in terms of its effectiveness to identify different pollutants including heavy metals. The MTSI showed stronger relationship to total deformity incidence expressed as percentage. Additionally, the multivariate RDA model showed higher capability of MTSI to explain the variations in heavy metal contents of the river sediments. The MTSI was recommended in bioassessment of water and sediment quality using the mentum deformities of Chironomus spp. larvae from aquatic ecosystems receiving anthropogenic, agricultural, or industrial discharges. PMID:20697808

  1. Fullerenes(nC60) affect the growth and development of the sediment-dwelling invertebrate Chironomus riparius larvae.

    Science.gov (United States)

    Waissi-Leinonen, Greta C; Nybom, Inna; Pakarinen, Kukka; Akkanen, Jarkko; Leppänen, Matti T; Kukkonen, Jussi V K

    2015-11-01

    The possible toxicity of nanoparticles (NPs) to aquatic organisms needs to be investigated for chronic effects at low concentrations. Chronic effects of carbon NPs, fullerenesC60, on the midges of Chironomus riparius at different life stages on larvae and adult midges were investigated. Sediment associated fullerenesC60 were studied by 10-day growth and 42-day emergence tests with artificial sediment at nominal concentration ranges 0.0004-80 mg/kg dry weight. The body length decreased in the lower tested concentrations (0.0025-20 mg/kg), but the effect vanished with higher concentrations. Delayed emergence rate observed at 0.5 mg/kg. The observed effects correlated with analyzed sediment particle sizes indicating that small agglomerates of fullerene have more significant effects on C. riparius than larger agglomerates observed with higher C60 doses. The results reveal that fullerene may pose risks to benthic organisms, emerging as changes in the ecotoxic parameters studied here which inflects by the survival of the population. PMID:26142746

  2. Assessment of the effect of nanomaterials on sediment-dwelling invertebrate Chironomus tentans larvae.

    Science.gov (United States)

    Oberholster, P J; Musee, N; Botha, A-M; Chelule, P K; Focke, W W; Ashton, P J

    2011-03-01

    Studies were conducted to determine the effects of a panel of seven nanomaterials (NMs), namely: α-alumina, γ-alumina, precipitated silica; silica fume, calcined silica fume, colloidal antimony pentoxide (Sb(2)O(5)), and superfine amorphous ferric oxide (Fe(2)O(3)), on sediment dwelling invertebrates Chironomus tentans under controlled laboratory conditions. Percentage survival, enzyme activities, growth development, and DNA fragmentation parameters were studied as acute, biochemical, and physiological toxicities of NMs, respectively. Quantitation of catalase and peroxidase enzyme activity demonstrated that toxicant stress of the NMs increased enzyme activity in a concentration dependent fashion across all treatments. The percentage growth length of the test specimens exposed to different NMs was significantly reduced compared to the negative control while only five concentrations were not in the toxic range, namely; Fe(2)O(3) (5 μg/kg); silica fume (5 μg/kg, 50 μg/kg); Sb(2)O(5) (5 μg/kg) and calcined silica fume (5 μg/kg). Genotoxic stress assessed by use of DNA laddering showed complementary findings to the other ecotoxicological endpoints tested in this study--the percentage survival and growth length inhibition. PMID:21216008

  3. 60Co accumulation from sediment and planktonic algae by midge larvae (Chironomus luridus)

    International Nuclear Information System (INIS)

    This paper reports the results of several experiments carried out to evaluate uptake and retention by a limicolous midge larva of 60Co retained in sediment, either adsorbed on mineral particles or bound to planktonic algae. In order to determine their relative contributions in radionuclide accumulation, the different vectors (water, algae and sediment) were first labelled individually and then simultaneously. 60Co accumulation from water and from algae results in a maximum concentration factor of 30 and in a mean trophic transfer factor of 4·5 × 10−3. The level of contamination of midge larvae from sediment is markedly influenced by the presence of endogenous organic matter. Thus the radionuclide transfer factor is about twice as high for larvae placed in labelled raw sediment than for larvae placed in labelled incinerated sediment, in the presence as in the absence of contaminated planktonic algae. Irrespective of the contamination conditions, 60Co depuration from midge larvae is a very rapid phenomenon that corresponds, in all cases, to a radionuclide half-life of only a few days

  4. Carbon and nitrogen stable isotope ratios analysis of food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) in strongly acidic lake Katanuma

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Hideyuki [Tohoku Univ., Sendai (Japan). Graduate School of Science; Kikuchi, Eisuke; Shikano, Shuichi

    2001-12-01

    The food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) were analyzed using carbon and nitrogen stable isotope ratios in Lake Katanuma. Lake Katanuma is a volcanic and strongly acidic lake (average pH 2.2). In Lake Katanuma, potential sources of diets for the chironomid larvae are limited including a benthic diatom (Pinnularia braunii), a phytoplankton (Chlamydomonas acidophila), sulfate oxidizing bacteria, and vascular plants supplied from vegetation surrounding the lake. Based on the average carbon and nitrogen isotope ratios among these potential sources and sediment, benthic diatoms were considered to be most probable food source of the chironomid larvae. {delta}{sup 13}C values of the chironomid were significantly different among seasons and habitat depths, suggesting that diet of C. acerbiphilus changed seasonally and with habitat depth. (author)

  5. Carbon and nitrogen stable isotope ratios analysis of food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) in strongly acidic lake Katanuma

    International Nuclear Information System (INIS)

    The food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) were analyzed using carbon and nitrogen stable isotope ratios in Lake Katanuma. Lake Katanuma is a volcanic and strongly acidic lake (average pH 2.2). In Lake Katanuma, potential sources of diets for the chironomid larvae are limited including a benthic diatom (Pinnularia braunii), a phytoplankton (Chlamydomonas acidophila), sulfate oxidizing bacteria, and vascular plants supplied from vegetation surrounding the lake. Based on the average carbon and nitrogen isotope ratios among these potential sources and sediment, benthic diatoms were considered to be most probable food source of the chironomid larvae. δ13C values of the chironomid were significantly different among seasons and habitat depths, suggesting that diet of C. acerbiphilus changed seasonally and with habitat depth. (author)

  6. In situ bioassays with Chironomus riparius larvae to biomonitor metal pollution in rivers and to evaluate the efficiency of restoration measures in mine areas

    International Nuclear Information System (INIS)

    In this study we evaluate the ability of an in situ bioassay with Chironomus riparius larvae, using larval development and growth as endpoints, to biomonitor water quality and to assess the biological recovery of metal contaminated freshwater ecosystems of mine areas that are subject of restoration measures. The bioassay was carried out in streams located near an abandoned goldmine in North Portugal, throughout an environmental rehabilitation of the mine (2002-2004). During this period, a decrease in the inhibition of larval growth in the metal contaminated stream was observed. The bioassay was also performed in streams located near an active tungsten mine in Central Portugal. Larval growth and development were highly inhibited in the stream that receives acid drainage from the tungsten mine and treated water from the AMD treatment station. The results indicate that the bioassay can be used to evaluate the efficiency of environmental restoration measures in mining areas. - In situ bioassays with Chironomus riparius larvae can be a suitable tool to monitor restoration efficiency after a long time of metallic sediment contamination

  7. Nucleolar organizer (NO) size as a measure of instantaneous growth in Chironomus riparius larvae (Diptera: Chironomidae) : a tool for monitoring individual and population responses to stress

    Energy Technology Data Exchange (ETDEWEB)

    Martin, J.P.; Ciborowski, J.J.; Wytrykush, C. [Windsor Univ., Windsor, ON (Canada)

    2009-07-01

    This presentation reported on 2 laboratory experiments that were conducted using Chironomus riparius larvae to relate nucleolar growth (NO) size to chironomid growth. In one experiment, 5 treatments varied in diet quality only, which was manipulated by providing midge larvae with 1.0 mg of food per individual per day, but varying the ratio of Tetramin to non-nutritious methyl-cellulose. A second experiment followed a 2 x 2 factorial design. The factors were growth period and diet quality. Diet quality and growth period were found to influence the individual biomass considerably. NO size was related to the quality of the diet provided at the end of the experiment, regardless of larval biomass. Therefore, NO size appears to be related to growth rate at time of collection rather than larval size. The authors proposed using NO size of larvae in natural populations as a measure of growth on which to base estimates of secondary production and as a new way to monitor individual and population responses to environmental stress. Preliminary field measurements of larval production and NO size from oil sands-affected and reference wetlands were found to be consistent with laboratory results.

  8. Nucleolar organizer (NO) size as a measure of instantaneous growth in Chironomus riparius larvae (Diptera: Chironomidae) : a tool for monitoring individual and population responses to stress

    International Nuclear Information System (INIS)

    This presentation reported on 2 laboratory experiments that were conducted using Chironomus riparius larvae to relate nucleolar growth (NO) size to chironomid growth. In one experiment, 5 treatments varied in diet quality only, which was manipulated by providing midge larvae with 1.0 mg of food per individual per day, but varying the ratio of Tetramin to non-nutritious methyl-cellulose. A second experiment followed a 2 x 2 factorial design. The factors were growth period and diet quality. Diet quality and growth period were found to influence the individual biomass considerably. NO size was related to the quality of the diet provided at the end of the experiment, regardless of larval biomass. Therefore, NO size appears to be related to growth rate at time of collection rather than larval size. The authors proposed using NO size of larvae in natural populations as a measure of growth on which to base estimates of secondary production and as a new way to monitor individual and population responses to environmental stress. Preliminary field measurements of larval production and NO size from oil sands-affected and reference wetlands were found to be consistent with laboratory results.

  9. Effects of uranium-contaminated sediments on the bioturbation activity of Chironomus riparius larvae (Insecta, Diptera) and Tubifex tubifex worms (Annelida, Tubificidae).

    Science.gov (United States)

    Lagauzère, S; Boyer, P; Stora, G; Bonzom, J-M

    2009-07-01

    Freshwater sediments represent a compartment for accumulation of toxic substances, notably of metallic pollutants such as uranium. However, they also constitute a privileged habitat for many benthic macro-invertebrate species with important roles in the functioning of these ecosystems, particularly through their bioturbation activities. Uranium accumulation in sediments can thus have harmful effects on these organisms (e.g., developmental delay, malformations, mortality). The present study aimed to evaluate the consequences of these effects on the bioturbation activity of Chironomus riparius larvae and Tubifex tubifex worms. These two species, which are widespread in freshwater ecosystems, are characteristic of two different modes of bioturbation: bioirrigation and upward bioconveying, respectively. By quantifying the burial and redistribution of fluorescent particulate tracers (microspheres), sediment reworking induced by these macro-invertebrates was measured after 12d of exposure. Biodiffusion D(b) and bioadvection W rates, as well as several other parameters, were estimated to assess and compare the bioturbation activity of the two species, separately and in combination, between uncontaminated and uranium-spiked sediments. The results reveal that C. riparius larvae were more sensitive to uranium, but their bioturbation activity, even under uncontaminated conditions, had little effect on sediment reworking. Particle mixing was mainly induced by T. tubifex worms, which were only affected by uranium at high concentrations in the sediment. Finally, bioturbation by T. tubifex led to a high degree of uranium release from sediment to the overlying water, which highlights the crucial role of this mostly dominant species on uranium biogeochemical cycles at concentrations existing in naturally contaminated sites. PMID:19403158

  10. Effects of acid-volatile sulfide on metal bioavailability and toxicity to midge (Chironomus tentans) larvae in black shale sediments

    Science.gov (United States)

    Ogendi, G.M.; Brumbaugh, W.G.; Hannigan, R.E.; Farris, J.L.

    2007-01-01

    Metal bioavailability and toxicity to aquatic organisms are greatly affected by variables such as pH, hardness, organic matter, and sediment acid-volatile sulfide (AVS). Sediment AVS, which reduces metal bioavailability and toxicity by binding and immobilizing metals as insoluble sulfides, has been studied intensely in recent years. Few studies, however, have determined the spatial variability of AVS and its interaction with simultaneously extracted metals (SEM) in sediments containing elevated concentrations of metals resulting from natural geochemical processes, such as weathering of black shales. We collected four sediment samples from each of four headwater bedrock streams in northcentral Arkansa (USA; three black shale-draining streams and one limestone-draining stream). We conducted 10-d acute whole-sediment toxicity tests using the midge Chironomus tentans and performed analyses for AVS, total metals, SEMs, and organic carbon. Most of the sediments from shale-draining streams had similar total metal and SEM concentrations but considerable differences in organic carbon and AVS. Zinc was the leading contributor to the SEM molar sum, averaging between 68 and 74%, whereas lead and cadmium contributed less than 3%. The AVS concentration was very low in all but two samples from one of the shale streams, and the sum of the SEM concentrations was in molar excess of AVS for all shale stream sediments. No significant differences in mean AVS concentrations between sediments collected from shale-draining or limestone-draining sites were noted (p > 0.05). Midge survival and growth in black shale-derived sediments were significantly less (p < 0.001) than that of limestone-derived sediments. On the whole, either SEM alone or SEM-AVS explained the total variation in midge survival and growth about equally well. However, survival and growth were significantly greater (p < 0.05) in the two sediment samples that contained measurable AVS compared with the two sediments from the

  11. Investigating a potential mechanism of Cd resistance in Chironomus riparius larvae using kinetic analysis of calcium and cadmium uptake

    International Nuclear Information System (INIS)

    The uptake kinetics of waterborne Ca and Cd, both independently and in combination, were examined in C. riparius larvae, which are extremely Cd tolerant. Larvae exposed to Ca (100-2500 μmol L-1), exhibited classic Michaelis-Menten saturation kinetics for Ca influx, measured using 45Ca as a radio-tracer. The maximum rate of Ca influx (JmaxCa) was 0.39 μmol g-1 h-1, and the Ca concentration where the carrier reached half saturation (KMCa) was 289 μmol L-1. Cd influx was measured using 109Cd as a radio-tracer in larvae exposed to Cd (0-1400 μmol L-1) while the Ca concentration was set to the KMCa. This revealed a JmaxCd (2.26 μmol g-1 h-1) which was nearly 6-fold higher that of Ca. This unusually high capacity for Cd uptake is in accordance with the huge tissue Cd burdens that chironomid larvae are able to accumulate during high level exposures. The apparent KMCd (1133 μmol Cd L-1), when recalculated to account for the background Ca level, was still high (567 μmol Cd L-1), suggesting that this organism has a low affinity for Cd relative to most aquatic animals, indeed lower or comparable to its affinity for Ca. In consequence, even well above environmentally relevant Cd exposures, C. riparius does not accumulate Cd at the expense of Ca, thereby avoiding internal hypocalcaemia, in contrast to most other organisms which are much more sensitive to Cd. However, Ca influx was significantly reduced when 1200 μmol Cd L-1 was added to Ca exposures (96-2410 μmol L-1). Michaelis-Menten analysis revealed a similar JmaxCa in Cd-exposed and control larvae (i.e. exposed only to Ca), but that the apparent KMCa was many-fold higher in larvae which were simultaneously exposed to Ca and Cd. Conversely, increasing Ca concentrations (96-2410 μmol L-1) progressively inhibited Cd uptake from a Cd exposure concentration (1200 μmol L-1), providing additional support for a common transport system. These results suggest that the interaction of Cd and Ca in C. riparius is one of

  12. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation.

    Science.gov (United States)

    Gaikwad, Pallavi S; Panicker, Lata; Mohole, Madhura; Sawant, Sangeeta; Mukhopadhyaya, Rita; Nath, Bimalendu B

    2016-08-01

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. PMID:27237970

  13. Improvement of crop technology in Asparagus plumosus Bak. A

    Directory of Open Access Journals (Sweden)

    Dumitru ZAHARIA

    1997-08-01

    Full Text Available Improvement of crop technology in Asparagus plumosus Bak. A 0,1% nutritive solution of the N, P, K, elements in raport of 3:1:2; 4:2:3 and 4:3:3 respectively was used to fertilise the plants Asparagus plumosus Bak., for the period between February and Octomber. A 29,8 to 35,20 posesive semnificative increase production of the shoot number per m2 was obtained. The quality of the shoots was not semnificatively influenced by the applied fertilisation system but it appeared to be determined by the cultural factors, light and temperature.

  14. Chironomus group classification according to the mapping of polytene chromosomes

    Science.gov (United States)

    Salleh, Syafinaz; Kutty, Ahmad Abas

    2013-11-01

    Chironomus is one of the important genera in Chironomidae family since they are widely diverse and abundance in aquatic ecosystem. Since Chironomus is very diverse, taxonomic work on this genus is very difficult and incomplete. Objective of this study is to form group classification of Chironomus according to the polytene chromosome mapping. The specific characteristics of polytene chromosomes in the salivary gland appeared to be particularly promising for taxonomic diagnosis of chironomid species. Chironomid larvae were collected from pristine sites at Sg. Langat and cultured in laboratory to reach fourth instar stage. The salivary glands were removed from larvae and chromosomes were stained with aceto orcein. Results showed that polytene chromosomes of Chironomus comprise of three long metacentric or submetacentric arms (BF, CD and AE arms) and one short acrocentric (G arm). In regards to nucleolar organizing region (NOR), Balbiani ring (BR), puffings and chromosome rearrangement, a number of four groups of different banding patterns were found. Two groups called as G group A and B have common NOR on arm BF and BR on arm G. However, group A has rearrangement pattern on arm CD and not in group B. This makes group B separated from group A. Another two groups called as groups C and D do not have common NOR on arm BF and also BR on arm G. Groups C and D were separated using arms G and arm AE. At arm G, only group C rearrangement pattern at unit 23c whereas group D was found to have large NOR at arm G and as well as arm AE, only group D has rearrangement pattern at unit 12c. This study indicates that chromosome arrangement could aid in revealing Chironomus diversity.

  15. New gnat-midge species chironomus degelenus i sp. n. (diptera chironomidae)

    International Nuclear Information System (INIS)

    For the first time the morphology of larvae, pupae, imago and karyotype of Chironomus degelenus I Sp. n. collected from Water-Body D-3-3 of the Degelen Mountain Massif has been described. The larvae have a species-specific structure and color of the head capsule, ventral-mental blades, and mandibula hamuli. The male gnat is characterized for grid structure in IX tergite. The karyotype of C. degelenus I Sp. n. has the following combination of chromosome arms: AB, CD, EF, and G (thummi complex), which is typical for Chironomus species. It was concluded that the origin of the new species of Chironomus degelenus I Sp. N. is related to the long-term genetic processes of Chironomini adaptation to the elevated radiation background level. (author)

  16. TOXICITY OF VERTICAL SEDIMENTS IN THE TRENTON CHANNEL, DETROIT RIVER, MICHIGAN, TO CHIRONOMUS TENTANS (INSECTA: CHIRONOMIDAE)

    Science.gov (United States)

    The objective of this study was to determine the effects of sediment from various sediment core depths on survival and weight gain of larvae of the dipteran midge, Chironomus tentans, during 10-d laboratory exposures. ediment cores were collected from 12 sites in the Trenton Chan...

  17. Cloning and expression of an atrazine inducible cytochrome P450 from Chironomus tentans (Diptera: Chironomidae)

    Science.gov (United States)

    Previous studies performed in our lab have measured the effect of atrazine exposure on cytochrome P450-dependent monooxygenase activity and have found increased activity in midge larvae (Chironomus tentans) as a result of atrazine exposure (1-10 ppm). Here we report the cloning and expression of a ...

  18. A new record of Chironomus (Chironomus) acidophilus Keyl (Diptera, Chironomidae) from the Uzon volcanic caldera (Kronotsky Reserve, Kamchatka Peninsula, Russia), its karyotype, ecology and biology.

    Science.gov (United States)

    Orel, Oksana V; Lobkova, Ludmila E; Zhirov, Sergey V; Petrova, Ninel A

    2015-01-01

    Morphology, cytology, ecology and biology of Holarctic Chironomus (Chironomus) acidophilus Keyl, 1960 (Diptera, Chironomidae) was examined from material collected in the geothermal Vosmerka Lake (pH=2.0-2.5). An illustrated redescription of C. acidophilus is given on the basis of adult males reared from field-collected pupae, and of simultaneously collected larvae. Additional larvae belonging to the pseudothummi-complex were identified as C. acidophilus on the basis of their karyotype. The karyotype of C. acidophilus (2n=8) and detailed mapping of the 4 chromosome arms A, E, D and F are provided. The population of C. acidophilus from Kamchatka was found to be karyologically monomorphic. Information on distribution and ecology of C. acidophilus from Vosmerka Lake (total mineralization 1583.5 mg/l) is also given. Chironomus acidophilus is the only species of aquatic insects recorded in this lake. Lack of competition and a richness of food resources contribute to the high abundance (35161 ind./m2) and biomass (11.342 g/m2) of the larvae of C. acidophilus in Vosmerka Lake. PMID:26249988

  19. Morpho-histological characterization of immature of the bioindicator midge Chironomus sancticaroli Strixino and Strixino (Diptera, Chironomidae)

    OpenAIRE

    Vinicius Sobrinho Richardi; Maiara Vicentini; Débora Rebechi; Luis Fernando Fávaro; Mário Antônio Navarro-Silva

    2015-01-01

    ABSTRACTChironomidae immature are used as bioindicators of sediment quality in aquatic ecosystems and ecotoxicological assays. Histological descriptions for this family are outdated and limited and there are no studies with Neotropical species. The aim of this study was to describe the tissue architecture of several organs of the larva of Chironomus sancticaroli. For the description of the histological pattern, the larvae were fixed in Duboscq solution for insects at 56 °C, followed by routin...

  20. Genotoxic effect of Phenanthrene on Chironomus sancticaroli (Diptera: Chironomidae

    Directory of Open Access Journals (Sweden)

    Gisele dos Santos Morais

    2014-08-01

    Full Text Available Phenanthrene, a Polycyclic Aromatic Hydrocarbon, remains adsorbed to sedimentary particles in aquatic environments. It affects mainly benthic organisms, and is considered potentially genotoxic. In ecotoxicology, species of Chironomus Meigen, 1803 are widely known as bioindicators of the effects of chemicals on aquatic organisms. This study investigates the effects of phenanthrene on the size of the head capsule of Chironomus sancticaroli Strixino & Strixino, 1981 larvae after chronic (eight days exposure, and DNA damage after acute (96 hours and chronic exposure (eight days, under laboratory conditions. DNA damage, evaluated using the alkaline comet assay, detected effects for both exposure periods, indicating that phenanthrene is toxic for C. sancticaroli. For the acute exposure, we analyzed five concentrations of phenanthrene, between 0.16 mg.l-1 and 1.60 mg.l-1, detecting significant differences (Kruskall-Wallis test with p < 0.05 in the degree of DNA damage in all groups. These effects were not dose-dependent. For the chronic exposure, two concentrations (0.16 mg.l-1, 0.83 mg.l-1 were analyzed, and DNA damage was observed in both. Again, the effects were not dose-dependent. This indicates that phenanthrene is genotoxic to larvae of C. sancticaroli even at low concentrations. The size of the head capsule was evaluated after chronic exposure to concentrations of 0.16 mg.l-1 and 0.83 mg.l-1. Significant differences (ANOVA test with p < 0.05 were detected in the two concentrations, and a reduction in the size of the larval head capsule was observed. This suggests that phenanthrene causes delay in larval development. These results indicate that phenanthrene affects the development of and causes DNA damage in C. sancticaroli larvae. Therefore, we suggest that C. sancticaroli can be used as a biological indicator for environmental contamination with phenanthrene.

  1. Setting the reference for the use of Chironomus sancticaroli (Diptera: Chironomidae) as bioindicator: Ontogenetic pattern of larval head structures

    OpenAIRE

    Débora Rebechi; Mário Antônio Navarro-Silva

    2012-01-01

    Species of Chironomidae are widely used as bioindicators of water quality, since their larvae undergo morphological deformities when in contact with sediment contaminated with chemicals. In this work we endeavored to study the morphology of head structures (antennae, mandible, mentum, pecten epipharyngis, ventromental plate and premandible) throughout the development of the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981, which can be used in environmental impact anal...

  2. Patterns of Fluctuating Asymmetry and Shape Variation in Chironomus riparius (Diptera, Chironomidae) Exposed to Nonylphenol or Lead

    Science.gov (United States)

    Arambourou, Hélène; Beisel, Jean-Nicolas; Branchu, Philippe; Debat, Vincent

    2012-01-01

    Deformities and fluctuating asymmetry in chironomid larvae have been proposed as sensitive indicators of biological stress and are commonly used to assess the ecological impact of human activities. In particular, they have been associated in Chironomus riparius, the most commonly used species, with heavy metal and pesticide river pollution. In this study, the effect of lead and 4-nonylphenol on mouthpart morphological variation of Chironomus riparius larvae was investigated by traditional and geometric morphometrics. For this purpose, first to fourth instar larvae were exposed to sediment spiked with lead (from 3.0 to 456.9 mg/kg dry weight) or 4-NP (from 0.1 to 198.8 mg/kg dry weight). Mentum phenotypic response to pollutants was assessed by four parameters: (1) the frequency of deformities, (2) fluctuating asymmetry of mentum length, (3) fluctuating asymmetry of mentum shape and (4) the mentum mean shape changes. Despite the bioaccumulation of pollutants in the chironomid’s body, no significant differences between control and stressed groups were found for mouthpart deformities and fluctuating asymmetry of mentum length. Slight effects on mentum shape fluctuating asymmetry were observed for two stressed groups. Significant mean shape changes, consisting of tooth size increase and tooth closing, were detected for lead and 4-NP exposure respectively. Those variations, however, were negligible in comparison to mentum shape changes due to genetic effects. These results suggest that the use of mentum variation as an indicator of toxic stress in Chironomus riparius should be considered cautiously. PMID:23133660

  3. Genotoxic effect of copper on salivary gland polytene chromosomes of Chironomus riparius Meigen 1804 (Diptera, Chironomidae)

    International Nuclear Information System (INIS)

    The genotoxic action of copper (Cu) on the polytene chromosomes of Chironomus riparius was investigated by analysing structural and functional chromosome aberrations of fourth instars larvae hatched from eggs subject to acute (48 h) exposure with three environmentally relevant concentrations of aqueous Cu (0.005, 0.01, 0.05 mg/l). A dose dependent relationship was observed between Cu concentration and frequency of chromosomal aberrations. A significantly higher frequency of functional alterations, specifically decondensed centromeres and telomeres, and reduction in activity of Balbiani rings, was observed in treated material compared to control. A comparison of breakpoints resulting from treatment with chromium and lead from earlier studies with those Cu-induced identified a series of chromosomal weak points particularly vulnerable to trace metals. We also show that the appearance of structural and functional chromosome aberrations are more sensitive indicators of acute Cu toxicity in chironomid larvae than changes in external morphology. - Acute exposure of Chironomus eggs to copper resulted in changes in chromosome structure and function

  4. Genotoxic effect of copper on salivary gland polytene chromosomes of Chironomus riparius Meigen 1804 (Diptera, Chironomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Michailova, P. [Institute of Zoology, Bulgarian Academy of Sciences, 1 Tzar Osvoboditel boul., Sofia 1000 (Bulgaria)]. E-mail: michailova@zoology.bas.bg; Petrova, N. [Institute of Zoology, Russian Academy of Sciences, St. Petersburg, 199034, Universit. nab. 1, Russia (Russian Federation); Ilkova, J. [Institute of Zoology, Bulgarian Academy of Sciences, 1 Tzar Osvoboditel boul., Sofia 1000 (Bulgaria); Bovero, S. [Department of Animal Biology, University of Turin, via Albertina 13, Turin (Italy); Brunetti, S. [Department of Animal Biology, University of Turin, via Albertina 13, Turin (Italy); White, K. [School of Biological Sciences, University of Manchester, Manchester M13 9PT (United Kingdom); Sella, G. [Department of Animal Biology, University of Turin, via Albertina 13, Turin (Italy)

    2006-11-15

    The genotoxic action of copper (Cu) on the polytene chromosomes of Chironomus riparius was investigated by analysing structural and functional chromosome aberrations of fourth instars larvae hatched from eggs subject to acute (48 h) exposure with three environmentally relevant concentrations of aqueous Cu (0.005, 0.01, 0.05 mg/l). A dose dependent relationship was observed between Cu concentration and frequency of chromosomal aberrations. A significantly higher frequency of functional alterations, specifically decondensed centromeres and telomeres, and reduction in activity of Balbiani rings, was observed in treated material compared to control. A comparison of breakpoints resulting from treatment with chromium and lead from earlier studies with those Cu-induced identified a series of chromosomal weak points particularly vulnerable to trace metals. We also show that the appearance of structural and functional chromosome aberrations are more sensitive indicators of acute Cu toxicity in chironomid larvae than changes in external morphology. - Acute exposure of Chironomus eggs to copper resulted in changes in chromosome structure and function.

  5. Responses of the aquatic midge Chironomus riparius to DEET exposure.

    Science.gov (United States)

    Campos, Diana; Gravato, Carlos; Quintaneiro, Carla; Soares, Amadeu M V M; Pestana, João L T

    2016-03-01

    N,N-diethyl-3-methylbenzamide (DEET) is the active ingredient of many commercial insect repellents. Despite being detected worldwide in effluents, surface water and groundwater, there is still limited information on DEET's toxicity toward non-target aquatic invertebrates. Thus, our main objective was to assess the effects of DEET in the life cycle of Chironomus riparius and assess its biochemical effects. Laboratory assays showed that DEET reduced developmental rates (reduced larval growth, delayed emergence) of C. riparius larvae and also caused a decrease in the size of adult midges. Concerning the biochemical responses, a short exposure to DEET caused no effects in lipid peroxidation, despite the significant inhibition of catalase and glutathione-S-transferase activities and of total glutathione contents. Moreover, inhibition of acetylcholinesterase activity was also observed showing neurotoxic effects. Environmental risk assessment of insect repellents is needed. Our results showed moderate toxicity of DEET toward C. riparius, however, due to their mode of action, indirect ecological effects of DEET and of other insect repellents cannot be excluded and should be evaluated. PMID:26773354

  6. Apedilum griseistriatum comb. nov., placement of Chironomus (Polypedilum griseistriatum (Diptera, Chironomidae

    Directory of Open Access Journals (Sweden)

    Mariano Donato

    2015-03-01

    Full Text Available The study of the type material of Chironomus (Polypedilum griseistriatum Edwards, 1931 described from Patagonia lead us to formally transfer the species to Apedilum Townes, 1945 as a new combination, and a reared specimen allows us to describe its pupa. Based on several larvae belonging to Apedilum collected in the proximity of the localities in which the adults and pupae were found, we tentatively describe the larval stage. Subfossil larval head capsules of the same species were found in Laguna Stibnite at 46°S in Chile dated to about 2,500 years ago and in Puerto Blest, Lago Nahuel Huapi at 41°S in Argentina dated about 2,000 years ago. We discuss the habitat of the species based on both modern and subfossil material. Identification keys to male adult, pupae and fourth instar larvae are also provided.

  7. Effect of gamma irradiation on larval longevity of Chironomus Riparius Meigen. Vol. 4

    International Nuclear Information System (INIS)

    Whole body irradiation is known to shorten the life-span of insects. This is further investigated in aquatic insect larvae, as part of a programme concerned with stress responses on these larvae. The effect of gamma rays on the longevity of different larval instars of midge Chironomus Riparius was investigated by using five doses of 1, 9, 30, 200 and 1000 Gy of gamma rays. Lt50 (the time in days required for killing 50% of the population) was estimated using spssx programme. Data showed that irradiation decreased Lt50 in the second, third and fourth instars in comparison to their control, while in the first instar, irradiation increased Lt50 for all doses used. Shortening or increasing life was independent of the dose. Results were explained in terms of possibility of inhibition of enzymes. 1 fig., 1 tab

  8. Tolerance to desiccation stress in Chironomus Ramosus through plasticity in homeostatic control

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    Leena Thorat

    2015-07-01

    Full Text Available Desiccating environments pose physiological challenges to organisms, especially those experiencing them on recurring basis. Several desiccation-tolerant organisms are known to withstand loss of body water in response to seasonal dehydration patterns through adaptations that facilitate their sustenance in the dry state followed by recovery upon return of favourable hydrating conditions. In the present study, we have chosen Chironomus ramosus, an aquatic midge species as a laboratory model system towards the exploration of its desiccation tolerance ability. We confirm that upon desiccation exposure at low relative humidity, larvae of C. ramosus exhibited rapid water loss and could revive upon rehydration. Moreover, the revived individuals underwent successful metamorphosis; albeit delayed. This heterochrony in the developmental calendar was experimentally verified by the investigation of ecdysone levels which suggested an altered pattern of ecdysis in response to the stress. These data suggested the organism’s plasticity in developmental homeostasis when confronted with dehydration stress. Furthermore, spectrofluorometric assays indicated the occurrence of thiol damage in the larvae. Investigation of Hsp70, the evolutionarily conserved stress responsive gene suggested that Hsp70 was indeed up-regulated during the rehydration period, thus facilitating recovery of the larvae from dehydration. In summary, several lines of evidence involving cellular, physiological and developmental adaptations revealed the ability of C. ramosus larvae to minimize the diverse categories of damage caused by desiccation stress through plasticity in their homeostatic mechanism.

  9. Consequences of Physical Disturbance by Tadpoles and Snails on Chironomid Larvae

    OpenAIRE

    Gargi Pal; Gautam Aditya; Niladri Hazra

    2014-01-01

    Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck), and Red-rimmed melania, Melanoides tuberculata (Müller), and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider), on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction...

  10. Cadmium transport by the gut and Malpighian tubules of Chironomus riparius

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Erin M., E-mail: leonarem@mcmaster.ca [Department of Biology, McMaster University, Hamilton, ON, L8S 4K1 (Canada); Pierce, Laura M. [Department of Biology, McMaster University, Hamilton, ON, L8S 4K1 (Canada); Gillis, Patricia L. [Aquatic Ecosystem Protection Research Division, Environment Canada, Burlington, ON, L7R 4A6 (Canada); Wood, Chris M.; O' Donnell, Michael J. [Department of Biology, McMaster University, Hamilton, ON, L8S 4K1 (Canada)

    2009-05-05

    Many aquatic insects are very insensitive to cadmium in short-term laboratory studies. LC50 values for larvae of the midge Chironomus riparius are over 25,000 times the Criterion Maximum Concentration in the United States Environmental Protection Agency (U.S. EPA (2000)) species sensitivity distribution (SSD). Excretion or sequestration of cadmium may contribute to insensitivity and we have therefore examined cadmium transport by isolated guts and renal tissues of C. riparius larvae. Regional differences of Cd transport along the gut were identified using a Cd{sup 2+}-selective microelectrode in conjunction with the Scanning Ion-Selective Electrode Technique (SIET). Cd is transported into the anterior midgut (AMG) cells from the lumen and out of the cells into the hemolymph. The transport of Cd from the gut lumen to the hemolymph exposes other tissues such as the nervous system and muscles to Cd. The gut segments which remove Cd from the hemolymph at the highest rate are the posterior midgut (PMG) and the ileum. In addition, assays using an isolated Malpighian (renal) tubule preparation have shown that the Malpighian tubules (MT) both sequester and secrete Cd. For larvae bathed in 10 {mu}mol l{sup -1} Cd, the tubules can secrete the entire hemolymph burden of Cd in {approx}15 h.

  11. Cadmium transport by the gut and Malpighian tubules of Chironomus riparius

    International Nuclear Information System (INIS)

    Many aquatic insects are very insensitive to cadmium in short-term laboratory studies. LC50 values for larvae of the midge Chironomus riparius are over 25,000 times the Criterion Maximum Concentration in the United States Environmental Protection Agency (U.S. EPA (2000)) species sensitivity distribution (SSD). Excretion or sequestration of cadmium may contribute to insensitivity and we have therefore examined cadmium transport by isolated guts and renal tissues of C. riparius larvae. Regional differences of Cd transport along the gut were identified using a Cd2+-selective microelectrode in conjunction with the Scanning Ion-Selective Electrode Technique (SIET). Cd is transported into the anterior midgut (AMG) cells from the lumen and out of the cells into the hemolymph. The transport of Cd from the gut lumen to the hemolymph exposes other tissues such as the nervous system and muscles to Cd. The gut segments which remove Cd from the hemolymph at the highest rate are the posterior midgut (PMG) and the ileum. In addition, assays using an isolated Malpighian (renal) tubule preparation have shown that the Malpighian tubules (MT) both sequester and secrete Cd. For larvae bathed in 10 μmol l-1 Cd, the tubules can secrete the entire hemolymph burden of Cd in ∼15 h.

  12. Effects of Activated Carbon on PCB Bioaccumulation and Biological Responses of Chironomus riparius in Full Life Cycle Test.

    Science.gov (United States)

    Nybom, Inna; Abel, Sebastian; Waissi, Greta; Väänänen, Kristiina; Mäenpää, Kimmo; Leppänen, Matti T; Kukkonen, Jussi V K; Akkanen, Jarkko

    2016-05-17

    The nonbiting midge Chironomus riparius was used to study the remediation potential and secondary effects of activated carbon (AC, ø 63-200 μm) in PCB contaminated sediments. AC amendments efficiently reduced PCB bioavailability determined by Chironomus riparius bioaccumulation tests and passive samplers. PCBs were shown to transfer from larvae to adults. Lower PCB concentrations were observed in adult midges emerging from AC amended compared to unamended sediments. Increased reproduction, survival, larval growth and gut wall microvilli length were observed with low AC dose (0.5% sediment dw) compared to unamended sediment, indicating an improved success of larvae in the sediment with low organic carbon content. On the other hand, higher AC doses (2.5% sediment dw) caused adverse effects on emergence and larval development. In addition, morphological changes in the gut wall microvilli layer were observed. This study showed that the secondary effects of AC amendments are dependent on the dose and the sediment characteristics. Metamorphic species, such as C. riparius, may act as a vector for organic pollutants from aquatic to terrestrial ecosystems and according to this study the AC amendments may reduce this transport. PMID:27100921

  13. Morpho-histological characterization of immature of the bioindicator midge Chironomus sancticaroli Strixino and Strixino (Diptera, Chironomidae

    Directory of Open Access Journals (Sweden)

    Vinicius Sobrinho Richardi

    2015-09-01

    Full Text Available ABSTRACTChironomidae immature are used as bioindicators of sediment quality in aquatic ecosystems and ecotoxicological assays. Histological descriptions for this family are outdated and limited and there are no studies with Neotropical species. The aim of this study was to describe the tissue architecture of several organs of the larva of Chironomus sancticaroli. For the description of the histological pattern, the larvae were fixed in Duboscq solution for insects at 56 °C, followed by routine histologic processing, infiltration in paraffin, and the sections were stained with Hematoxylin–Eosin. After examining the slides, the tube digestive, salivary gland, excretory, nervous, endocrine, circulatory, and integumentary systems and fat body were histologically characterized. The histology allows evaluation of cell morphology, and for being not expensive and easily accessible can be routinely used in biomonitoring. In addition, is a useful tool in ecotoxicological assays and allow to evaluate biomarkers at tissue and cell levels.

  14. Experimental evidence for cadmium uptake via calcium channels in the aquatic insect Chironomus staegeri

    International Nuclear Information System (INIS)

    We used the chironomid Chironomus staegeri to investigate the mechanism of cadmium (Cd) uptake in aquatic insects. We exposed C. staegeri larvae to a low nominal Cd concentration (50 nM) for 3 days and measured the effects of calcium (Ca) concentration (0.1-10 mM Ca) as well as the Ca channel blockers lanthanum and verapamil on Cd accumulation. When Ca2+ concentrations were increased above a control (0.1 mM Ca2+) to 1-10 mM, Cd accumulation by larvae was inhibited by from 46 to 88%, respectively. A simple theoretical model of Cd-Ca competition for uptake sites fitted our observations well. Cadmium accumulation was significantly inhibited in a concentration-dependent manner by both La (73% at 10 μM and 92% at 100 μM) and verapamil (59% at 100 μM and 85% at 300 μM). Our findings represent strong evidence that Cd entry into these insects occurs through Ca channels. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  15. Determination of larval instars in Chironomus sancticaroli (Diptera: Chironomidae using novel head capsule structures

    Directory of Open Access Journals (Sweden)

    Vinicius S. Richardi

    2013-04-01

    Full Text Available Determining the age composition of a population is important when conducting ecological, taxonomic and environmental assessments. Morphometric measurements of the head capsule, especially the length and width, are widely used in the identification of insect instars, but alternative ways for determining the age of insects can expand the options for the analysis of field and laboratory populations. This study evaluated the morphometry of the antennae, mandibles, mentum and ventromental plates to discriminate among the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981. The larvae were reared in the laboratory under constant temperature (25°C and photoperiod of 12/12 hours for 19 days, with a supply of food. Fifteen larvae were removed randomly every day, cleared in KOH, and slide-mounted, and had the antennae, mandibles, mentum and ventromental plates measured. The dimensions of the four structures studied allowed us to statistically distinguish each of the four larval instars. The data fit an exponential equation according to the Brooks-Dyar rule, which allows an estimate of the larval instar of specimens collected in the field, even when development takes place under different conditions. The duration of each instar was also obtained from our data, and showed an overlap of instars during development.

  16. Mouthparts deformities in chironomid larvae (Chironomidae, Diptera) in Labe river basin in years 1993-1999

    International Nuclear Information System (INIS)

    We have studied the occurrences of mouth part deformities in chironomid larvae, which are regarded as a sublethal effect resulting from larval exposure to toxicants. These endpoint have been used in several cases as bio-indicator for sediment pollution. Material for the study was collected from eight localities of the rivers Labe and Vltava (six and two localities, respectively) in 1993, 1996 and 1999. We selected two common chironomid genera, Chironomus and Glyptotendipes, for the analysis of morphological abnormalities. We investigated two types of abnormalities: 1) apparent mechanical damage, and 2) abnormal deformities such as mentum gaps, split or missing teeth on the mentum, etc. We found a different occurrence of deformities between the two genera. We detected higher frequencies of deformities in populations of Chironomus larvae (0-57 %) than in populations of Glyptotendipes larvae (0-19 %). We suggest that the genus Chironomus is a more sensitive indicator of toxic stress. The highest frequency of mouth part deformities in chironomid larvae was detected in the middle part of the river Labe which is contaminated by various agricultural and industrial chemicals. (authors)

  17. Karyotype characteristics and polymorphism peculiarities of Chironomus bernensis Wülker & Klötzli, 1973 (Diptera, Chironomidae) from the Central Caucasus and Ciscaucasia

    Science.gov (United States)

    Karmokov, Mukhamed Kh.; Polukonova, Natalia V.; Sinichkina, Olga V.

    2015-01-01

    Abstract Data about the karyotype characteristics, features of chromosomal polymorphism and larval morphology of populations of Chironomus bernensis Wülker & Klötzli, 1973 (Diptera, Chironomidae) from the Central Caucasus (the northern macroslope) and Ciscaucasia are presented. The characteristics of the pericentromeric regions of the long chromosomes of this species from Caucasian populations were very similar to the ones from some European populations (from Poland and Italy), but differed from Swiss and Siberian populations. In the North Caucasian populations 10 banding sequences were found: two in arms A, C, and E, and one in arms B, D, F, and G. Nine of them were already known for this species, and one, berC2, is described for the first time. Cytogenetic distances between all the studied populations of Chironomus bernensis show that close geographical location of all studied populations from the Central Caucasus and Ciscaucasia is reflected in their similar cytogenetic structure, but on the other hand, that they are more closely related to populations from Europe than to populations from Western Siberia. At the same time, all studied larvae from Caucasian populations have a four-bladed premandible, instead of a two-bladed one, as in the description of Chironomus bernensis from Switzerland (Wülker and Klötzli 1973, Polukonova 2005c). These peculiarities may indicate the relative isolation of the Caucasus from the viewpoint of microevolution. Further research on karyological and morphological characteristics of Chironomus bernensis from geographically distant regions is necessary as there is a possibility that the presently known species is actually polytypic and consists of several sibling species. PMID:26312128

  18. Hypoxia and anoxia effects on alcohol dehydrogenase activity and hemoglobin content in Chironomus riparius Meigen, 1804

    Directory of Open Access Journals (Sweden)

    Valentina Grazioli

    2016-02-01

    Full Text Available The metabolic effects of low oxygen content on alcohol-dehydrogenase (ADH activity and hemoglobin (Hb concentration were investigated in IV-instar larvae of Chironomus riparius (Diptera: Chironomidae from an Italian stream. Two series of short-term (48 h experiments were carried out: exposure to (1 progressive hypoxia (95 to 5% of oxygen saturation and (2 anoxia (at <5% of oxygen saturation. In (1, Hb amount increased with increasing oxygen depletion up to a critical value of oxygenation (about 70% of oxygen saturation. Below this percentage, the Hb amount declined to values comparable with those present in the control. The respiration rate (R remained almost constant at oxygen saturation >50% and decreased significantly only after 48 h of treatment (= <5% of oxygen saturation reaching values <100 mmolO2 gAFDW-1 h-1. ADH activity showed two phases of growth, within the first 14 h and over 18 h of exposure. Overall, we inferred that i Hb might function as short-term oxygen storage, enabling animals to delay the on-set of anaerobiosis; and ii alcoholic fermentation co-occurs for a short time with aerobic respiration, becoming the prevalent metabolic pathway below 5% of oxygen saturation (<1 mg L-1. These considerations were supported also by results from anoxia exposure (2. In such condition, larvae were visibly stressed, becoming immobile after few minutes of incubation, and ADH reached higher values than in the hypoxia treatment (2.03±0.15 UADH mg prot-1. Overall, this study showed a shift from aerobic to anaerobic activity in C. riparius larvae exposed to poorly oxygenated water with an associated alteration of ADH activity and the Hb amount. Such metabolites might be valid candidate biomarkers for the environmental monitoring of running waters.

  19. Setting the reference for the use of Chironomus sancticaroli (Diptera: Chironomidae as bioindicator: Ontogenetic pattern of larval head structures

    Directory of Open Access Journals (Sweden)

    Débora Rebechi

    2012-04-01

    Full Text Available Species of Chironomidae are widely used as bioindicators of water quality, since their larvae undergo morphological deformities when in contact with sediment contaminated with chemicals. In this work we endeavored to study the morphology of head structures (antennae, mandible, mentum, pecten epipharyngis, ventromental plate and premandible throughout the development of the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981, which can be used in environmental impact analyses. Our results show that it is possible to differentiate among larval instars by doing a quantitative analysis on the number of striae on the ventromental plates. The six structures analyzed changed during larval ontogeny. These changes are part of the ontogeny of the immature stages not exposed to xenobiotics. We believe that the morphological pattern defined in this work can be used for comparisons with ontogenetic changes observed in field studies conducted in polluted environments.

  20. Some observations of buccal deformities in chironomid larvae (diptera: chironomidae) from the ciénaga grande de santa marta, colombia

    OpenAIRE

    RISS WOLFGANG; KAHLHEBER ANTJE; WERDING BERND

    2013-01-01

    The mouthpart deformities of chironomid larvae are considered as indicators ofenvironmental stress caused by water pollution such as heavy metals, pesticides, butas well by organic contamination. In the present study larvae from the side channelsof the Ciénaga Grande de Santa Marta were investigated. The chironomid communityof the channels are dominated by species of the genera Goeldichironomus andChironomus. All together 21 taxa were determined. The average proportion of mouthpartdeformities...

  1. Life-cycle effects of sediment-associated uranium on Chironomus riparius (diptera: chironomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Dias, V.; Ksas, B.; Camilleri, V.; Bonzom, J.M. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    In aquatic ecosystems, sediments function as reservoir for many of the more persistent chemicals that are introduced into surface waters. Sediments provide a habitat for various benthic macro-invertebrates, which are exposed to sediment-associated chemicals both directly and via food intake. These chemicals may be directly toxic to benthic macro-invertebrates and can be integrated into food chain. Benthic macro-invertebrates play an important role in the ecosystem structure and functioning. In particular, they represent an important component of aquatic food chains. Among the non biologically essential metals, data concerning uranium fate and effects on freshwater benthic invertebrates are sparse. The present study aimed to estimate effects of a chronic uranium exposure on life-cycle traits of Chironomus riparius. To achieve this goal, (i) first instar larvae were exposed to a series of concentrations of uranium via the sediment, and (ii) a number of developmental (e.g. growth) and reproductive (e.g. emergence, fecundity, viability) endpoints, through parental and into F1 generations, were evaluated. Within the framework of ecological risk assessment, these data will help the derivation of a sediment guideline value for uranium that does not currently exist in France or elsewhere due to a lack of toxicity data. (author)

  2. The Use of the Developmental Rate of the Aquatic Midge Chironomus riparius (Diptera, Chironomidae) in the Assessment of the Postsubmersion Interval.

    Science.gov (United States)

    González Medina, Alejandro; Soriano Hernando, Óscar; Jiménez Ríos, Gilberto

    2015-05-01

    Nonbiting midges (Diptera, Chironomidae) are the most abundant members of the fauna associated with submerged carcasses, but their use in the medicolegal context is very restricted because of their complex ontogeny. In this case, the corpse of a woman was recovered in late spring from a river in Granada (Iberian Peninsula). It showed obvious signs of long permanence in the aquatic environment and, along with pulmonary and microscopical analyses, led to the conclusion that the cause of death was drowning. Several larvae-like specimens were sampled from the scalp and later identified by morphological external features as IV instar larvae of Chironomus riparius Meigen, 1804 (Diptera, Chironomidae). Sequencing of cytochrome oxidase subunit I was performed to confirm the identification. The knowledge of the biology of C. riparius at low temperatures was critical to assess a postsubmersion interval of 16-17 days. PMID:25613586

  3. Macrofaunal Impact on the Denitrifying Bacterial Community in Freshwater Sediment

    DEFF Research Database (Denmark)

    Poulsen, Morten; Stief, Peter; Schramm, Andreas

    Sediment-dwelling macroinvertebrates alter their habitat by transporting oxic water into the sediment and enriching it for organic matter, thereby affecting microbial processes in the sediment. Here we report that burrowing macroinvertebrates can also have a pronounced effect on microbial diversity......, with nitrate-reducing and denitrifying bacteria as examples. The diversity of these functional groups was compared in sediment microcosms with and without Chironomus plumosus larvae, using the genes encoding nitrate reductase (narG) and nitrous oxide reductase (nosZ) as functional markers. The...... estimated phylotype richness of narG increased from 68 in sediment without larvae to 170 in sediment with larvae. Part of this increase in narG diversity could be explained by metabolic activation of certain nitrate-reducing bacteria in the gut of C. plumosus, since 18.3 % of the additional phylotypes were...

  4. The basic repeat unit of a Chironomus Balbiani ring gene.

    OpenAIRE

    Bäumlein, H; Wobus, U; Gerbi, S A; Kafatos, F C

    1982-01-01

    A clone derived from the Balbiani ring b (BRb) gene of Chironomus thummi has been used to study the internal organization of that gene. Much of the gene consists of approximately 80 copies of a ca. 300 bp repeat unit, which are tandemly organized. The BRb clone contains a major part of that unit (242 bp). Sequence analysis shows that approximately 60% of the unit corresponds to short, tandemly organized subsequences, which encode peptides 8 to 11 residues long. In turn, each subsequence consi...

  5. Combined effects of Cu and UVR on survival and melanin synthesis in Chironomus riparius larvae

    NARCIS (Netherlands)

    M.L. de Baat; M. van Gemert; R.A. Verweij; R.A. Loayza Muro; M.H.S. Kraak

    2012-01-01

    The tropical Andes encompass vast areas with altitudes above 4000 m, where the combination of high UV radiation and metal pollution creates environments that challenge the survival and persistence of aquatic life. Since the pigment melanin counteracts the negative effects of UVR, and has the additio

  6. Combined effects of Cu and UVR on survival and melanin synthesis in Chironomus riparius larvae

    OpenAIRE

    Baat, de, M.L.; Gemert, van, F.H.M.; Verweij, R.A.; Loayza Muro, R.A.; Kraak, M.H.S.

    2012-01-01

    The tropical Andes encompass vast areas with altitudes above 4000 m, where the combination of high UV radiation and metal pollution creates environments that challenge the survival and persistence of aquatic life. Since the pigment melanin counteracts the negative effects of UVR, and has the additional ability to sequester metal cations, it has been hypothesized that melanin plays an important role in the ability of benthic invertebrates to persist under these harsh conditions. The aim of the...

  7. Algal food selection and digestion by larvae of the pestiferous chironomid Chironomus crassicaudatus under laboratory conditions

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Ali, A.; Lobinske, R. J.

    2004-01-01

    Roč. 20, č. 4 (2004), s. 458-461. ISSN 8756-971X Institutional research plan: CEZ:AV0Z6066911 Keywords : Chironomidae * nuisance midge * cyanobacteria Subject RIV: EH - Ecology, Behaviour Impact factor: 0.691, year: 2004

  8. Consequences of physical disturbance by tadpoles and snails on chironomid larvae.

    Science.gov (United States)

    Pal, Gargi; Aditya, Gautam; Hazra, Niladri

    2014-01-01

    Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck), and Red-rimmed melania, Melanoides tuberculata (Müller), and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider), on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction of selected above mentioned organisms. The direct effects of non-predator organisms on the midge larvae are due to physical disturbance that destroys their tubes. This may result in vulnerability of midge larvae to predators in the wild. So the community structure may be altered by indirect effects, where one or more species, through their direct disturbance, indirectly change the abundance of other species. PMID:24672384

  9. Consequences of Physical Disturbance by Tadpoles and Snails on Chironomid Larvae

    Directory of Open Access Journals (Sweden)

    Gargi Pal

    2014-01-01

    Full Text Available Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck, and Red-rimmed melania, Melanoides tuberculata (Müller, and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider, on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction of selected above mentioned organisms. The direct effects of non-predator organisms on the midge larvae are due to physical disturbance that destroys their tubes. This may result in vulnerability of midge larvae to predators in the wild. So the community structure may be altered by indirect effects, where one or more species, through their direct disturbance, indirectly change the abundance of other species.

  10. Combination effects of pyrethroids and neonicotinoids on development and survival of Chironomus riparius.

    Science.gov (United States)

    Kunce, Warren; Josefsson, Sarah; Örberg, Jan; Johansson, Frank

    2015-12-01

    Standard ecotoxicological risk assessments are conducted on individual substances, however monitoring of streams in agricultural areas has shown that pesticides are rarely present alone. In fact, brief but intense pulse events such as storm water runoff and spray drift during application subject freshwater environments to complex mixtures of pesticides at high concentrations. This study investigates the potential risks to non-target aquatic organisms exposed to a brief but intense mixture of the neonicotinoid pesticides imidacloprid and thiacloprid and the pyrethroid pesticides deltamethrin and esfenvalerate, compared to single substance exposure. All four of these pesticides have been detected in surface waters at concentrations higher than benchmark values and both classes of pesticides are known to exert adverse effects on non-target aquatic organisms under single substance exposure scenarios. First instar midge larvae of the non-target aquatic organism, Chironomus riparius, were exposed to combinations of these four pesticides at 50% of their LC50 (96 h) values in a 1h pulse. They were then reared to adulthood in uncontaminated conditions and assessed for survival, development time and fecundity. Our results show that the risk of disruption to survival and development of non-target aquatic organisms under this scenario is not negligible on account of the significant increases in mortality of C. riparius found in the majority of the pesticide exposures and the delays in development after pyrethroid exposure. While none of the deleterious effects appear to be amplified by combination of the pesticides, there is some evidence for antagonism. No effects on fecundity by any of the pesticide treatments were observed. PMID:26379201

  11. The effect of temperature gradients on endocrine signaling and antioxidant gene expression during Chironomus riparius development.

    Science.gov (United States)

    Park, Kiyun; Kwak, Ihn-Sil

    2014-02-01

    Temperature is one of the most important environmental factors affecting the biological processes of aquatic species. To investigate the potential effects of temperature on the developmental processes of aquatic invertebrates, we analyzed biological and molecular transcriptional responses during Chironomus riparius development, including five stages spanning from embryo to adult stages. We assessed the temperature change-induced reduction of survival rate, changes in biological development including the male:female ratio in emerged adults, the success rates of pupation and emergence, and the developmental timing of pupation and emergence. The increased temperature induced expression of endocrine signaling genes, such as the ecdysone receptor, ultraspiracle (ortholog of the RXR), and the estrogen-related receptor in the fourth-instar larval and pupal stages of C. riparius development. Altered temperature also affected the activity of antioxidant genes, including catalase, peroxidase, glutathione peroxidase, and superoxide dismutase during the fourth-instar larval to adult stages of C. riparius development, as a result of altered development. Increased temperature during the fourth-instar larval stage increased oxidative stress in pupae and adults. Responses of antioxidant genes to increased temperature occurred in a developmental stage-dependent manner. However, reduced temperature did not induce the expression of antioxidant genes in a developmental stage-dependent manner, although it did induce oxidative stress during C. riparius development. Increased temperature also caused greater toxicity of di-ethylhexyl phthalate (DEHP) in fourth-instar larvae. Our findings suggest that altered temperatures may disturb the invertebrate hormone system and developmental processes by inducing oxidative stress in aquatic environments. PMID:24239821

  12. Mercury tissue residue approach in Chironomus riparius: Involvement of toxicokinetics and comparison of subcellular fractionation methods.

    Science.gov (United States)

    Gimbert, Frédéric; Geffard, Alain; Guédron, Stéphane; Dominik, Janusz; Ferrari, Benoit J D

    2016-02-01

    Along with the growing body of evidence that total internal concentration is not a good indicator of toxicity, the Critical Body Residue (CBR) approach recently evolved into the Tissue Residue Approach (TRA) which considers the biologically active portion of metal that is available to contribute to the toxicity at sites of toxic action. For that purpose, we examined total mercury (Hg) bioaccumulation and subcellular fractionation kinetics in fourth stage larvae of the midge Chironomus riparius during a four-day laboratory exposure to Hg-spiked sediments and water. The debris (including exoskeleton, gut contents and cellular debris), granule and organelle fractions accounted only for about 10% of the Hg taken up, whereas Hg concentrations in the entire cytosolic fraction rapidly increased to approach steady-state. Within this fraction, Hg compartmentalization to metallothionein-like proteins (MTLP) and heat-sensitive proteins (HSP), consisting mostly of enzymes, was assessed in a comparative manner by two methodologies based on heat-treatment and centrifugation (HT&C method) or size exclusion chromatography separation (SECS method). The low Hg recoveries obtained with the HT&C method prevented accurate analysis of the cytosolic Hg fractionation by this approach. According to the SECS methodology, the Hg-bound MTLP fraction increased linearly over the exposure duration and sequestered a third of the Hg flux entering the cytosol. In contrast, the HSP fraction progressively saturated leading to Hg excretion and physiological impairments. This work highlights several methodological and biological aspects to improve our understanding of Hg toxicological bioavailability in aquatic invertebrates. PMID:26688328

  13. Survival, reproduction, and arsenic body burdens in Chironomus riparius exposed to arsenate and phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Mogren, Christina L., E-mail: christina.mogren@email.ucr.edu [Department of Entomology, University of California, Riverside, 900 University Ave, Riverside, CA 92521 (United States); Kiparski, Guntram R. von; Parker, David R. [Department of Environmental Science, University of California, Riverside, 900 University Ave, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, 900 University Ave, Riverside, CA 92521 (United States)

    2012-05-15

    Despite the increasing awareness of arsenic (As) contamination in surface waters worldwide, little is known about how As alone and in the presence of other chemicals affects aquatic insects. Larvae of Chironomus riparius were exposed in a laboratory investigation to factorial combinations of 0, 0.13, 2.0, 5.3, and 13 {mu}mol As l{sup -1} and 0, 0.15, and 15 {mu}mol PO{sub 4} l{sup -1} throughout development from first instar to pupal emergence. The time between male and female emergence increased from 1.8 {+-} 0.17 days to 2.9 {+-} 0.34 days with exposure at higher As levels. The highest As exposure also decreased the number of eggs per egg mass, which may affect population maintenance. For these parameters, there was no effect from PO{sub 4}, and no interaction between As and PO{sub 4}. Total As determination of larval and adult tissues was conducted using Hydride Generated Atomic Absorption Spectroscopy (HGAAS) and revealed concentrations ranging from 2.48 {+-} 0.363 to 30.5 {+-} 0.473 {mu}g/g and 1.03 {+-} 0.286 to 8.97 {+-} 0.662 {mu}g/g, respectively, indicating elimination of approximately 72% of total As body burdens between the fourth instar and adult stages. There was no effect of PO{sub 4}, indicating PO{sub 4} does not alter uptake of As in C. riparius. The potential for movement of As to terrestrial systems exists, though trophic transfer may be more likely during the aquatic larval stage. - Highlights: Black-Right-Pointing-Pointer We evaluate how sublethal concentrations of As and P affect C. riparius. Black-Right-Pointing-Pointer High As exposure significantly increased the time between male and female emergence. Black-Right-Pointing-Pointer High As exposure significantly decreased the number of eggs per egg mass. Black-Right-Pointing-Pointer Fourth instar larvae eliminate 72% of As body burdens before the adult stage.

  14. Effects of clay minerals and organic matter in formulated sediments on the bioavailability of sediment-associated uranium to the freshwater midge, Chironomus dilutus

    International Nuclear Information System (INIS)

    It is well established that bioavailability influences metal toxicity in aquatic ecosystems. However, the factors and mechanisms that influence uranium (U) bioavailability and toxicity in sediment have not been thoroughly evaluated, despite evidence that suggests different sediment components can influence the sorption and interaction of some metals. Given that dissolved U is generally accepted as being the primary bioavailable fraction of U, it is hypothesized that adsorption and interaction of U with different sediment components will influence the bioavailability of U in sediment. We investigated the effects of key sediment physicochemical properties on the bioavailability of U to a model freshwater benthic invertebrate, Chironomus dilutus. Several 10-day spiked sediment bioaccumulation experiments were performed, exposing C. dilutus larvae to a variety of formulated sediments spiked with different concentrations of U (5, 50 and/or 200 mg U/kg d.w.). Mean accumulation of U in C. dilutus larvae decreased significantly from 1195 to 10 mg U/kg d.w. as kaolin clay content increased from 0% to 60% in sediment spiked with 50 mg U/kg d.w. Similarly, higher organic matter content also resulted in a significant reduction of U bioaccumulation in C. dilutus larvae, indicating a reduction in U bioavailability. Concentrations of U in both the overlying water and sediment pore water displayed a strong positive relationship to U bioaccumulation in C. dilutus larvae (r2 = 0.77, p < 0.001 and r2 = 0.57, p < 0.001, respectively) for all experiments, while total U concentrations in the sediment had a poor relationship to U bioaccumulation (r2 = 0.10, p = 0.028). Results from this research confirm that sediment clay and organic matter content play a significant role in altering U bioavailability, which is important in informing risk assessments of U contaminated sites and in the development of site-specific sediment quality guidelines for U. - Highlights: • We examined the role

  15. Effects of clay minerals and organic matter in formulated sediments on the bioavailability of sediment-associated uranium to the freshwater midge, Chironomus dilutus

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Sarah E., E-mail: sarah.crawford@usask.ca [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3 (Canada); Liber, Karsten, E-mail: karsten.liber@usask.ca [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3 (Canada); School of Environment and Sustainability, 117 Science Place, University of Saskatchewan, Saskatoon, SK S7N 5C8 (Canada); Institute of Loess Plateau, 92 Wucheng Road, Shanxi University, Taiyuan, Shanxi 030006 (China)

    2015-11-01

    It is well established that bioavailability influences metal toxicity in aquatic ecosystems. However, the factors and mechanisms that influence uranium (U) bioavailability and toxicity in sediment have not been thoroughly evaluated, despite evidence that suggests different sediment components can influence the sorption and interaction of some metals. Given that dissolved U is generally accepted as being the primary bioavailable fraction of U, it is hypothesized that adsorption and interaction of U with different sediment components will influence the bioavailability of U in sediment. We investigated the effects of key sediment physicochemical properties on the bioavailability of U to a model freshwater benthic invertebrate, Chironomus dilutus. Several 10-day spiked sediment bioaccumulation experiments were performed, exposing C. dilutus larvae to a variety of formulated sediments spiked with different concentrations of U (5, 50 and/or 200 mg U/kg d.w.). Mean accumulation of U in C. dilutus larvae decreased significantly from 1195 to 10 mg U/kg d.w. as kaolin clay content increased from 0% to 60% in sediment spiked with 50 mg U/kg d.w. Similarly, higher organic matter content also resulted in a significant reduction of U bioaccumulation in C. dilutus larvae, indicating a reduction in U bioavailability. Concentrations of U in both the overlying water and sediment pore water displayed a strong positive relationship to U bioaccumulation in C. dilutus larvae (r{sup 2} = 0.77, p < 0.001 and r{sup 2} = 0.57, p < 0.001, respectively) for all experiments, while total U concentrations in the sediment had a poor relationship to U bioaccumulation (r{sup 2} = 0.10, p = 0.028). Results from this research confirm that sediment clay and organic matter content play a significant role in altering U bioavailability, which is important in informing risk assessments of U contaminated sites and in the development of site-specific sediment quality guidelines for U. - Highlights: • We

  16. TOXICITY OF TWO HERBICIDES 2,4 -D DIMETHYLAMINE AND BENSULFURON METHYL TO RICE FIELD CHIRONOMUS KIIENSIS (TOKUNAGA) ( DIPTERA: CHIRONOMIDAE)

    Institute of Scientific and Technical Information of China (English)

    Al-Shami S A; Che Salmah M R; Siti Azizah M N; Abu Hassan A; Azmi M

    2006-01-01

    Fourth instar larvae of Chironomus kiiensis(Tokunaga) were exposed to various concentrations of two commonly used herbicides: 2,4 - D Dimethylamine and Bensulfuron methyl in the rice fields. The bioassay experiment was carried out in a rearing unit in the laboratory at a room temperature ( (27 ± 2) ℃ ). A thin layer of sand sediments and tissue papers were provided as substrate in each unit. Each concentration of all herbicides was prepared in 250 mL distilled water. The experiment was performed in triplicate and 20 chironomid larvae were placed in each rearing unit. The larvae were fed with fish food (Sanyuichiban(R)) at 2 d intervals and all units were aerated by air pumps. The experiment was monitored every 24 h for mortality of C. kiiensis. The 2,4 - D Dimethylamine bioassay was carried out for 24 h while Bensulfuron methyl was run for 72 h. Dead larvae, pupae and living or dead adults were counted and removed daily.The LC50 of 2,4 - D Dimethylamine was 2 638 mg ai L-1, more than 2 000 times higher than the recommended dose of 0.753 mg ai L-1 used for controlling weeds in the rice field. Bensulfuron methyl was more toxic than the 2,4 - D Dimethylamine. The LC50 of the Bensulfuron methyl was recorded at 1.29 mg ai L-1, and approximately was more 20 times than that of the recommended dose of 0. 057 mg ai L-1. Bensulfuron methyl was found to be slow acting. The mortality of the larvae was only observed after 72 h. However, this herbicide interfered with the emergence of C. kiiensis to adults at and above the recommended dose used in the rice fields. Based on their LC50 values, this study showed that applying these herbicides in the rice fields at doses recommended by the manufacturers was safe for C. kiiensis and presumably to other living organisms in the water.

  17. Application of Tritiated Compounds to the Midge Chironomus and some Aspects of the Metabolism of Salivary Gland Chromosomes

    International Nuclear Information System (INIS)

    The investigations were carried out on the salivary gland chromosomes of Chironomus tentons. Tritiated compounds (H3-thymidine, H3-uridine, H3-amino-acids), injected into the haemolymph of the larvae should indicate the place of incorporation within the giant chromosomes. After fixation of the salivary glands autoradiographs of the squash-preparations were made. The autoradiographs show that giant chromosomes are most suitable to localize the activity at chromosomal structures with high resolution. DNA-synthesis (thymidine), RNA-synthesis (uridine) and protein-synthesis within the cell could be followed by determining the time and approximatively the quantity of incorporation: Contrary to the protein-synthesis, the DNA-synthesis and the RNA-synthesis are restricted to the chromosomes. The essential physiological activity of the chromosomes seems to be represented by RNA synthesis which takes place at certain distinct loci (nuceolar organizers, ''Balbiani-rings'', puffs, and other chromosomal bands). The report discusses some features of RNA synthesis. (author)

  18. Potential use of acetylcholinesterase, glutathione-S-transferase and metallothionein for assessment of contaminated sediment in tropical chironomid, Chironomus javanus.

    Science.gov (United States)

    Somparn, A; Iwai, C B; Noller, B

    2015-11-01

    Heavy metals and organophosphorus insecticide is known to act as disruptors for the enzyme system, leading to physiologic disorders. The present study was conducted to investigate the potential use of these enzymes as biomarkers in assessment of contaminated sediments on tropical chironomid species. Acetylcholinesterase (AChE), glutathione-S-transferase (GST) and metallothionein (MT) activity was measured in the fourth-instar chironomid larvae, Chironomus javanus, Kieffer, after either 48-hr or 96-hr exposure to organophosphorus insecticide, chlorpyrifos (0.01- 0.25 mg kg(-1)) or heavy metal cadmium (0.1-25 mg kg(-1)). Exposure to chlorpyrifos (0.01 mg kg(-1)) at 48 and 96 hr significantly of AChE activity (64.2%-85.9%) and induced GST activity (33.9-63.8%) when compared with control (P GST activity (11.7-40%) and MT level (9.0%-70.5%) when compared with control (P impact of enzyme activity on chlorpyrifos and cadmium contamination. Activity of AChE, GST and MT could serve as potential biomarkers for assessment and biomonitoring the effects of insecticide and heavy metal contamination in tropical aquatic ecosystems. PMID:26688973

  19. Micro x-ray absorption spectroscopic analysis of arsenic localization and biotransformation in Chironomus riparius Meigen (Diptera: Chironomidae) and Culex tarsalis Coquillett (Culicidae)

    International Nuclear Information System (INIS)

    The distribution and speciation of arsenic (As) were analyzed in individuals of various life stages of a midge, Chironomus riparius, and the mosquito Culex tarsalis exposed to 1000 μg/l arsenate. X-ray absorption spectroscopy (XAS) revealed that C. riparius larvae accumulate As in their midgut, with inorganic arsenate [As(V)] being the predominant form, followed by arsenite [As(III)] and an As-thiol. Reduced concentrations of As in pupal and adult stages of C. riparius indicate excretion of As between the larval and pupal stages. In adults, As was limited to the thorax, and the predominant form was an As-thiol. In Cx. tarsalis, As was not found in high enough concentrations to determine As speciation, but the element was distributed throughout the larva. In adults, As was concentrated in the thorax and eyes of adults. These results have implications for understanding the biotransformation of As and its movement from aquatic to terrestrial environments. -- Highlights: •C. riparius larvae reduced arsenate to arsenite in the midgut. •C. riparius larvae accumulated As in the midgut, with 27% as a transformed As-thiol. •C. riparius adults retained As in the thorax, with 53% as As-thiol. •Larvae of Cx. tarsalis did not have a specific site of As accumulation. •Low concentrations of As in adults suggest reduced terrestrial transfer potential. -- Arsenic accumulation and biotransformation in aquatic insects is variable, but the location and speciation of As provides insight into the detoxification mechanisms of aquatic Diptera

  20. Chromosomal organization of the ribosomal RNA genes in the genus Chironomus (Diptera, Chironomidae

    Directory of Open Access Journals (Sweden)

    Larisa Gunderina

    2015-05-01

    Full Text Available Chromosomal localization of ribosomal RNA coding genes has been studied by using FISH (fluorescence in situ hybridization in 21 species from the genus Chironomus Meigen, 1803. Analysis of the data has shown intra- and interspecific variation in number and location of 5.8S rDNA hybridization sites in 17 species from the subgenus Chironomus and 4 species from the subgenus Camptochironomus Kieffer, 1914. In the majority of studied species the location of rDNA sites coincided with the sites where active NORs (nucleolus organizer regions were found. The number of hybridization sites in karyotypes of studied chironomids varied from 1 to 6. More than half of the species possessed only one NOR (12 out of 21. Two rDNA hybridization sites were found in karyotypes of five species, three – in two species, and five and six sites – in one species each. NORs were found in all chromosomal arms of species from the subgenus Chironomus with one of them always located on arm G. On the other hand, no hybridization sites were found on arm G in four studied species from the subgenus Camptochironomus. Two species from the subgenus Chironomus – Ch. balatonicus Devai, Wuelker & Scholl, 1983 and Ch. “annularius” sensu Strenzke, 1959 – showed intraspecific variability in the number of hybridization signals. Possible mechanisms of origin of variability in number and location of rRNA genes in the karyotypes of species from the genus Chironomus are discussed.

  1. Functional and structural rearrangements of salivary gland polytene chromosomes of Chironomus riparius Mg. (Diptera,Chironomidae) in response to freshly neutralized aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Michailova, P.; Ilkova, J.; White, K.N

    2003-05-01

    Aluminium impacts on aquatic biota can be detected using polytene chromosomes as bio-markers - Although recent work has shown that environmentally relevant concentrations of freshly neutralized aluminium (AI) are bioavailable and toxic to freshwater invertebrates, the genotoxicity of Al has not been examined. Here we show that freshly neutralized Al affects structure and function of the salivary gland polytene chromosomes of the ubiquitous chironomid larva Chironomus riparius over three generations. Exposure to 500 {mu}g l{sup -1} added Al for 24-25 days resulted in a significantly higher frequency of numerous somatic aberrations, while no structural aberrations were found in F1 controls and few in the second and third generation. Aberrations also included deletions of sections of chromosome G of C. riparius larvae as well as deletions of one or more Balbiani rings. Changes in functional activity included decreased activity of the Balbiani rings (BR), and an increase in the number of decondensed centromeres. The activity of the nucleolar organizer (NOR) significantly decreased in F1 chironomids exposed to Al, while in the F2 and F3 generations the NOR showed normal (high) activity. First generation chironomids were generally more susceptible to Al although no clear evidence of tolerance was apparent over three generations. The possible use of alterations in chironomid polytene chromosomes as biomarkers of trace metal pollution is discussed.

  2. Functional and structural rearrangements of salivary gland polytene chromosomes of Chironomus riparius Mg. (Diptera,Chironomidae) in response to freshly neutralized aluminium

    International Nuclear Information System (INIS)

    Aluminium impacts on aquatic biota can be detected using polytene chromosomes as bio-markers - Although recent work has shown that environmentally relevant concentrations of freshly neutralized aluminium (AI) are bioavailable and toxic to freshwater invertebrates, the genotoxicity of Al has not been examined. Here we show that freshly neutralized Al affects structure and function of the salivary gland polytene chromosomes of the ubiquitous chironomid larva Chironomus riparius over three generations. Exposure to 500 μg l-1 added Al for 24-25 days resulted in a significantly higher frequency of numerous somatic aberrations, while no structural aberrations were found in F1 controls and few in the second and third generation. Aberrations also included deletions of sections of chromosome G of C. riparius larvae as well as deletions of one or more Balbiani rings. Changes in functional activity included decreased activity of the Balbiani rings (BR), and an increase in the number of decondensed centromeres. The activity of the nucleolar organizer (NOR) significantly decreased in F1 chironomids exposed to Al, while in the F2 and F3 generations the NOR showed normal (high) activity. First generation chironomids were generally more susceptible to Al although no clear evidence of tolerance was apparent over three generations. The possible use of alterations in chironomid polytene chromosomes as biomarkers of trace metal pollution is discussed

  3. Functional and structural rearrangements of salivary gland polytene chromosomes of Chironomus riparius Mg. (Diptera,Chironomidae) in response to freshly neutralized aluminium.

    Science.gov (United States)

    Michailova, P; Ilkova, J; White, K N

    2003-01-01

    Although recent work has shown that environmentally relevant concentrations of freshly neutralized aluminium (AI) are bioavailable and toxic to freshwater invertebrates, the genotoxicity of Al has not been examined. Here we show that freshly neutralized Al affects structure and function of the salivary gland polytene chromosomes of the ubiquitous chironomid larva Chironomus riparius over three generations. Exposure to 500 microg l-1 added Al for 24-25 days resulted in a significantly higher frequency of numerous somatic aberrations, while no structural aberrations were found in F1 controls and few in the second and third generation. Aberrations also included deletions of sections of chromosome G of C. riparius larvae as well as deletions of one or more Balbiani rings. Changes in functional activity included decreased activity of the Balbiani rings (BR), and an increase in the number of decondensed centromeres. The activity of the nucleolar organizer (NOR) significantly decreased in F1 chironomids exposed to Al, while in the F2 and F3 generations the NOR showed normal (high) activity. First generation chironomids were generally more susceptible to Al although no clear evidence of tolerance was apparent over three generations. The possible use of alterations in chironomid polytene chromosomes as biomarkers of trace metal pollution is discussed. PMID:12628199

  4. Larvae for layers

    DEFF Research Database (Denmark)

    Bjerrum, Lotte; Fischer, Christian Holst; Nordentoft, Steen

    2013-01-01

    Companies and researchers are in close collaboration developing a container- based system for cultivating fly larvae at organic poultry farms. In a one week process, manure will be converted to compost and the live larvae will be harvested and used for feeding laying hens. The larvae are expected...

  5. Identification of transport processes in bioirrigated muddy sediments by [18F]fluoride PET (Positron Emission Tomography).

    Science.gov (United States)

    Roskosch, Andrea; Lewandowski, Jörg; Bergmann, Ralf; Wilke, Florian; Brenner, Winfried; Buchert, Ralph

    2010-06-01

    In aquatic environments transport processes across the sediment-water interface are intensified by bioirrigating macrozoobenthos. Transport processes caused by Chironomus plumosus larvae dwelling in U-tubes were investigated by dynamic small animal Positron Emission Tomography (PET) with [18F]fluoride. Significant tracer transport from the burrows into the sediment was detected; penetration was deeper at the outlet branch of the burrow than at the inlet branch. Hence, advection plays a significant role in exchange between water in the burrows and muddy sediment. PMID:20185319

  6. Identification of transport processes in bioirrigated muddy sediments by [18F]fluoride PET (Positron Emission Tomography)

    International Nuclear Information System (INIS)

    In aquatic environments transport processes across the sediment-water interface are intensified by bioirrigating macrozoobenthos. Transport processes caused by Chironomus plumosus larvae dwelling in U-tubes were investigated by dynamic small animal Positron Emission Tomography (PET) with [18F]fluoride. Significant tracer transport from the burrows into the sediment was detected; penetration was deeper at the outlet branch of the burrow than at the inlet branch. Hence, advection plays a significant role in exchange between water in the burrows and muddy sediment.

  7. Identification of transport processes in bioirrigated muddy sediments by [18F]fluoride PET (Positron Emission Tomography)

    Energy Technology Data Exchange (ETDEWEB)

    Roskosch, Andrea [Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin (Germany)], E-mail: roskosch@igb-berlin.de; Lewandowski, Joerg [Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin (Germany); Bergmann, Ralf [Radiopharmaceutical Biology Division, Forschungszentrum Dresden-Rossendorf, Bautzener Landstrasse 400, 01328 Dresden (Germany); Wilke, Florian [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Brenner, Winfried; Buchert, Ralph [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Present address: Department of Nuclear Medicine, Charite, Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)

    2010-06-15

    In aquatic environments transport processes across the sediment-water interface are intensified by bioirrigating macrozoobenthos. Transport processes caused by Chironomus plumosus larvae dwelling in U-tubes were investigated by dynamic small animal Positron Emission Tomography (PET) with [18F]fluoride. Significant tracer transport from the burrows into the sediment was detected; penetration was deeper at the outlet branch of the burrow than at the inlet branch. Hence, advection plays a significant role in exchange between water in the burrows and muddy sediment.

  8. Cytological and cytochemical characterization of the polytene chromosomes of Chironomus sancticaroli (Diptera: chironomidae)

    International Nuclear Information System (INIS)

    The chromosome complement of a Brazilian Chironomus Species, C. Sancticaroli, was analyzed cytochemically. The polytene Chromosomes were identified and characterized and the nucleolus organizer regions (NORs) were located by a technique of in situ hybridization and immunofluorescence. Constitutive heterochromatin and its distribution in relation to the NORs were studied. (Author)

  9. Gastromermis kolleonis n. sp. (Nematoda: Mermithidae), a Parasite of Midges (Chironomus sp. Chironomidae) from Argentina

    OpenAIRE

    de Doucet, Maria M. A.; Poinar, George O.

    1984-01-01

    Gastromermis kolleonis n. sp. (Nematoda: Mermithidae) is described from the Arroyo Saldan River in Córdoba, Argentina. This species parasitizes midges of the genus Chironomus (Chironomidae: Diptera). It is distinguished from other members of the genus by the presence of six longitudinal chords, vulval flaps, degree of ventral displacement of the mouth, and size and shape of the spicule and amphids.

  10. Method refinements for the midge life-cycle, Chironomus dilutus test

    Science.gov (United States)

    Larval stages of non-biting midges can be found in almost any freshwater ecosystem, and one of the commonly tested midges is Chironomus dilutus (Chironomidae, Diptera) which is used for toxicity testing and ecological risk assessment of freshwater contaminants. USEPA, ASTM, Envir...

  11. Ceriodaphnia and Chironomus in situ toxicity tests assessing the wastewater treatment efficacy of constructed wetlands

    International Nuclear Information System (INIS)

    In situ toxicity tests were designed for Ceriodaphnia dubia and Chironomus tentans as part of a larger study designed to assess the effectiveness of constructed wetlands for the treatment of wastewater produced by oil production at Suncor OSG. The artificial wetlands were 50m long by 3m wide, with three replicates of the control and the treatment. Each wetland had four sample sites equidistant along its length, creating a gradient of treatment from site A being the most toxic to site D being the least toxic. Each test was conducted twice during the summer of 1994. Both the Ceriodaphnia and Chironomus test cages were a flow through design to allow for maximal exposure to the water within the wetlands. Mortality and reproduction were used as endpoints for Ceriodaphnia, whereas mortality and growth were used as endpoints for the Chironomus test. Test durations were fifteen and ten days respectively. Chironomus had very high mortality along the entire wetlands whereas Ceriodaphnia survival and fecundity increased along the length of the treatment wetlands. Both organisms had low mortality and high growth/fecundity in the control wetlands

  12. Recovery of benthic macrofauna from chronic pollution in the sea area off a refinery plant, southwest Finland

    Energy Technology Data Exchange (ETDEWEB)

    Leppaekoski, E.J. (Inst. of Biology, Abo, Finland); Lindstroem, L.S.

    1978-05-01

    Quantitative field studies (density, wet weight biomass, Shannon diversity, species richness, evenness of distribution) on benthic sublittoral macrofauna were made in the vicinity of an oil refinery in southwest Finland before and after the installation of a new wastewater treatment plant that reduced the amount of oil and liquid effluents by ca. 90-95%. The number of species and species diversity increased during the 1st and 2nd yr after pollution abatement at the stations close to the former outflows. The amphipods pontoporeia affinis, Corophium volutator, and C. lacustre, midge larvae of the Chironomus plumosus-group, the oligochaete Tubifex costatus, the polychaetes Harmothoe sarsi and Polydora redeki, and the bivalve Cardium sp. were the most successful recolonizers of the 23 taxa sampled. The strong lethal effect of oil-contaminated sediments upon Chironomus plumosus larvae decreased markedly in laboratory experiments (LT50 was estimated at 7 d in 1973 and at 28 d in 1974; in 1975, 80-90% of the larvae survived for 28 d). Details of postabatement succession are discussed. The results demonstrate not only the recovery from chronic oil pollution but also the degree of ecological damage caused by previous continuous discharge of oil.

  13. Extensive larva migrans

    Directory of Open Access Journals (Sweden)

    Mehta Vandana Rai

    2004-01-01

    Full Text Available Larva migrans is characterized by tortuous migratory lesions of the skin caused by larvae of nematodes. A 26-year-old fisherman presented to us with complaints of an itchy eruption on his back and arms of two months′ duration. Clinical examination revealed multiple wavy serpentine tracts and fork like lesions with a raised absolute eosinophil count of 3800 cells/cmm. Biopsy was inconclusive. This case is reported to highlight the extensive involvement by larva migrans.

  14. Extensive larva migrans

    Directory of Open Access Journals (Sweden)

    Mehta Vandana Rai

    2004-11-01

    Full Text Available Larva migrans is characterized by tortuous migratory lesions of the skin caused by larvae of nematodes. A 26-year-old fisherman presented to us with complaints of an itchy eruption on his back and arms of two months′ duration. Clinical examination revealed multiple wavy serpentine tracts and fork like lesions with a raised absolute eosinophil count of 3800 cells/cmm. Biopsy was inconclusive. This case is reported to highlight the extensive involvement by larva migrans.

  15. Low malathion concentrations influence metabolism in Chironomus sancticaroli (Diptera, Chironomidae in acute and chronic toxicity tests

    Directory of Open Access Journals (Sweden)

    Débora Rebechi

    2014-09-01

    Full Text Available Low malathion concentrations influence metabolism in Chironomus sancticaroli (Diptera, Chironomidae in acute and chronic toxicity tests. Organophosphate compounds are used in agro-systems, and in programs to control pathogen vectors. Because they are continuously applied, organophosphates often reach water sources and may have an impact on aquatic life. The effects of acute and chronic exposure to the organophosphate insecticide malathion on the midge Chironomus sancticaroli are evaluated. To that end, three biochemical biomarkers, acetylcholinesterase (AChE, alpha (EST-α and beta (EST-β esterase were used. Acute bioassays with five concentrations of malathion, and chronic bioassays with two concentrations of malathion were carried out. In the acute exposure test, AChE, EST-α and EST-β activities declined by 66, 40 and 37%, respectively, at 0.251 µg L-1 and more than 80% at 1.37, 1.96 and 2.51 µg L-1. In chronic exposure tests, AChE and EST-α activities declined by 28 and 15% at 0.251 µg L-1. Results of the present study show that low concentrations of malathion can influence larval metabolism, indicating high toxicity for Chironomus sancticaroli and environmental risk associated with the use of organophosphates.

  16. The effect of 210Pb and stable lead on the induction of mouthpart deformities in chironomid larvae

    International Nuclear Information System (INIS)

    To determine whether mouthpart deformities in chironomid larvae from Port Hope Harbour, Ontario, are the result of exposure to ionizing radiation or heavy metals in the sediment, Chironomus tentans larvae were exposed in the laboratory to concentrations of 210Pb and stable lead representative of contaminant levels in the harbour. Exposure to 100, 1000, and 2000 Bq 210Pb·g-1 dry sediment had no effect on the survival, growth of the larvae or frequency of deformities. Likewise, exposure to 0.5 and 5.0 mg lead·g-1 dry sediment had no effect on the larvae, but exposure to 35.0 mg lead·g-1 dry sediment resulted in 100% mortality of the larvae. These results indicate that the observed mouthpart deformities in chironomid larvae in Port Hope Harbour are not the result of radiation exposure. They also indicate that heavy metals (lead) may be having an impact on the population. (author). 28 refs., 9 tabs., 4 figs

  17. Identification, characterization and expression profiles of Chironomus riparius glutathione S-transferase (GST) genes in response to cadmium and silver nanoparticles exposure

    International Nuclear Information System (INIS)

    In this study, we report the identification and characterization of 13 cytosolic GST genes in Chironomus riparius from Expressed Sequence Tags (ESTs) database generated using pyrosequencing. Comparative and phylogenetic analyses were undertaken with Drosophila melanogaster and Anopheles gambiae GSTs and 3 Delta, 4 Sigma, 1 each in Omega, Epsilon, Theta, Zeta and 2 unclassified classes of GSTs were identified and characterized. The relative mRNA expression levels of all of the C. riparius GSTs (CrGSTs) genes under different developmental stages were varied with low expression in the larval stage. The antioxidant role of CrGSTs was studied by exposing fourth instar larvae to a known oxidative stress inducer Paraquat and the relative mRNA expression to different concentrations of cadmium (Cd) and silver nanoparticles (AgNPs) for various time intervals were also studied. All the CrGSTs showed up- or down regulation to varying levels based upon the concentration, and duration of exposure. The highest mRNA expression was noticed in Delta3, Sigma4 and Epsilon1 GST class in all treatments. These results show the role of CrGST genes in defense against oxidative stress and its potential as a biomarker to Cd and AgNPs exposure.

  18. Key to marine arthropod larvae

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2012-03-01

    Full Text Available The scope of this key is restricted to the larvae of marine arthropods. The key is based solely on their morphology, patterns of body segmentation, numbers of appendages, and mode of locomotion. An effort has been made to treat all traditionally named larval forms, both planktonic and benthic. It is intended that this key be useful for a researcher working with archived museum specimens and therefore, does not include habitat information as a identifying trait, even though this information is usually available in the archived records. Within the phylum Arthropoda there are two sub-phyla and eleven classes having larval stages in the marineenvironment. Where feasible the original names of the various larval types have been used. Because this nomenclature is less commonly used today compared to the past, the more recent taxonomic affinities are included in parentheses after the original larval name. The key includes the following thirty-four larvae: Branchhiopoda nauplii; Cephalocarida nauplii; Mystacocarida nauplii; trilobite larva; protonymphon; hexapod larvae; Remipedia nauplii; nauplius - Y larvae; Cirripedia nauplii; Ascothoracida nauplii; Ostracoda nauplii; Euphausiacea nauplii; Penaeidea nauplii; Cyclopoida nauplii; Calanoida nauplii; Harpacticoida nauplii;Polyarthra nauplii; cypris larva; eryonecius larva; cypris-Y larva; elapthocaris larvae; mysis larvae; lucifer zoea; acetes zoea; acanthosoma larva; phyllosoma; antizoea larva; anomuran zoea; brachyuran zoea; calyptopis larvae; furcilia larva; crytopia larva; puerulus larva; alima larva.

  19. Effect of acute exposure to cadmium on the expression of heat-shock and hormone-nuclear receptor genes in the aquatic midge Chironomus riparius

    Energy Technology Data Exchange (ETDEWEB)

    Planello, R.; Martinez-Guitarte, J.L. [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain); Morcillo, G., E-mail: gmorcillo@ccia.uned.es [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain)

    2010-03-01

    Cadmium is a widespread and highly toxic pollutant of particular ecotoxicological relevance for aquatic ecosystems where it accumulates. To identify biomarkers for ecotoxicity monitoring, the effect of cadmium on the expression of different genes related to the stress response as well as to the ecdysone hormone-signalling pathway was studied in the aquatic larvae of Chironomus riparius (Diptera, Chironomidae), a standard test organism in aquatic toxicology testing. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was used to evaluate the effects of acute and short-term cadmium exposures (10 mM CdCl{sub 2}, 12 h and 24 h) on the expression of hsp70, hsc70, hsp90 and hsp40 genes, as well as on that of the ecdysone hormonal-receptor genes (EcR and usp). A significant 3-fold increase in the level of hsp70 gene transcripts was induced by the treatment, whereas neither the other stress genes tested (hsp90 and hsp40) nor the constitutive form of hsp70, hsc70, was affected in the larvae exposed to cadmium. These results show that hsp70 is differentially activated to other environmentally regulated heat-shock genes, and constitutes a biomarker of exposure to this toxic metal. In addition, we also found that cadmium is able to alter the expression of the ecdysone receptor gene (EcR), whose mRNA level is significantly increased whereas usp levels remained unaltered. This finding, evidenced for the first time in invertebrates, supports the view that cadmium has the ability to mimic the effect of the hormone by the activation of the ecdysone nuclear receptor, which may partly explain the endocrine disruption capability that has been previously suggested for this toxic metal. Our research adds to the growing evidence implicating heavy metals, and cadmium in particular, as potential endocrine disruptive agents and may have significant implications for ecological risk assessment of endocrine-disrupting compounds in invertebrates.

  20. Effect of acute exposure to cadmium on the expression of heat-shock and hormone-nuclear receptor genes in the aquatic midge Chironomus riparius

    International Nuclear Information System (INIS)

    Cadmium is a widespread and highly toxic pollutant of particular ecotoxicological relevance for aquatic ecosystems where it accumulates. To identify biomarkers for ecotoxicity monitoring, the effect of cadmium on the expression of different genes related to the stress response as well as to the ecdysone hormone-signalling pathway was studied in the aquatic larvae of Chironomus riparius (Diptera, Chironomidae), a standard test organism in aquatic toxicology testing. Reverse Transcription Polymerase Chain Reaction (RT-PCR) was used to evaluate the effects of acute and short-term cadmium exposures (10 mM CdCl2, 12 h and 24 h) on the expression of hsp70, hsc70, hsp90 and hsp40 genes, as well as on that of the ecdysone hormonal-receptor genes (EcR and usp). A significant 3-fold increase in the level of hsp70 gene transcripts was induced by the treatment, whereas neither the other stress genes tested (hsp90 and hsp40) nor the constitutive form of hsp70, hsc70, was affected in the larvae exposed to cadmium. These results show that hsp70 is differentially activated to other environmentally regulated heat-shock genes, and constitutes a biomarker of exposure to this toxic metal. In addition, we also found that cadmium is able to alter the expression of the ecdysone receptor gene (EcR), whose mRNA level is significantly increased whereas usp levels remained unaltered. This finding, evidenced for the first time in invertebrates, supports the view that cadmium has the ability to mimic the effect of the hormone by the activation of the ecdysone nuclear receptor, which may partly explain the endocrine disruption capability that has been previously suggested for this toxic metal. Our research adds to the growing evidence implicating heavy metals, and cadmium in particular, as potential endocrine disruptive agents and may have significant implications for ecological risk assessment of endocrine-disrupting compounds in invertebrates.

  1. Transcriptional profiling induced by pesticides employed in organic agriculture in a wild population of Chironomus riparius under laboratory conditions.

    Science.gov (United States)

    Lencioni, Valeria; Grazioli, Valentina; Rossaro, Bruno; Bernabò, Paola

    2016-07-01

    Copper (Cu) and azadirachtin (AZA-A+B) are pesticides allowed in organic agriculture whose environmental risk and toxicity for aquatic wildlife is only partially known. Reverse Transcription Polymerase Chain Reaction was used to assess the molecular effect of acute and short-term exposure (3, 24h) of Cu (0.01, 0.05, 1, 10, 25mgl(-1)) and AZA-A+B (0.2, 0.3, 0.4, 0.5, 1mgl(-1)) on the expression of five candidate genes (hsp70, hsc70, hsp40, hsp10 and cyP450) in a non-target species, Chironomus riparius. Fourth-instar larvae were collected from a mountain stream polluted by agricultural land run-off. All genes were responsive to both pesticides but each gene had a specific response to the different experimental concentrations and exposure times. A few similarities in transcriptional profiling were observed, such as a linear concentration-dependent response of hsp70 after 24h of exposure (at ≥1mgl(-1) of Cu and ≥0.2mgl(-1) of AZA-A+B) and an up-regulation regardless of the concentration of hsc70 after 24h of exposure (at ≥0mgl(-1) of Cu and ≥0.2mgl(-1) of AZA-A+B and the up-regulation of hsp70 after 3h of exposure at ~LC50 (Cu-LC50=26.1±2.5mgl(-1), AZA-A+B-LC50=1.1±0.2mgl(-1)). According to the results, hsp40, hsp10 and cyP450 may be defined as pesticide-dependent (i.e., hsp40 and hsp10 seemed to responded mainly to AZA-A+B and cyP450 to Cu), while hsc70 as time-dependent regardless of the pesticide (i.e., hsc70 responded only after 24h of treatment with Cu and AZA-A+B). This study gives new insights on the potential role of the C. riparius's hsps and cyP450 genes as sensitive biomarkers for freshwater monitoring. PMID:26994805

  2. Structural transition in inactive Balbiani ring chromatin of Chironomus during micrococcus nuclease digestion

    OpenAIRE

    Widmer, R. M.; Lezzi, M.; Koller, Th.

    1987-01-01

    We have analysed by micrococcus nuclease digestion the chromatin structure of genes in the Balbiani ring (BR) regions of a Chironomus cell line. Gel electrophoresis of the DNA fragments reveals a repeating structure which consists of two repeat sizes, a long repeat seen in the large fragments and a small repeat seen in the small fragments. The two repeats hardly overlap, except in a narrow transition zone which is at a different fragment size in the BR 2.2 and the BR 2.1 gene. The sizes of th...

  3. Inconsistency in the analysis of morphological deformities in chironomidae (Insecta: Diptera) larvae.

    Science.gov (United States)

    Salmelin, Johanna; Vuori, Kari-Matti; Hämäläinen, Heikki

    2015-08-01

    The incidence of morphological deformities of chironomid larvae as an indicator of sediment toxicity has been studied for decades. However, standards for deformity analysis are lacking. The authors evaluated whether 25 experts diagnosed larval deformities in a similar manner. Based on high-quality digital images, the experts rated 211 menta of Chironomus spp. larvae as normal or deformed. The larvae were from a site with polluted sediments or from a reference site. The authors revealed this to a random half of the experts, and the rest conducted the assessment blind. The authors quantified the interrater agreement by kappa coefficient, tested whether open and blind assessments differed in deformity incidence and in differentiation between the sites, and identified those deformity types rated most consistently or inconsistently. The total deformity incidence varied greatly, from 10.9% to 66.4% among experts. Kappa coefficient across rater pairs averaged 0.52, indicating insufficient agreement. The deformity types rated most consistently were those missing teeth or with extra teeth. The open and blind assessments did not differ, but differentiation between sites was clearest for raters who counted primarily absolute deformities such as missing and extra teeth and excluded apparent mechanical aberrations or deviations in tooth size or symmetry. The highly differing criteria in deformity assignment have likely led to inconsistent results in midge larval deformity studies and indicate an urgent need for standardization of the analysis. PMID:26061223

  4. Cytogenetic characteristics of Chironomus balatonicus Devai, Wulker, Scholl (Diptera, Chironomidae) from the Chernobyl region

    International Nuclear Information System (INIS)

    A cytogenetic analysis was carried out on a population of Chironomus balatonicus (Chironomidae, Diptera) from Chernobyl, a highly radioactive area of the Kiev region. Several chromosomal aberrations were established unique to a population of Chironomus balatonicus living in an area contaminated by radioactive waste. Five new heterozygous inversions, deficiencies in arms C, D, E, F and chromatid breaks were found in the irradiated population but not in nonirradiated populations. A pericentric inversion in chromosome AB occurred at a relatively high frequency. Genome aberrations expressed by a heterochromatized 'B' chromosome were evident. In the irradiated and nonirradiated populations common inversions occurred showing variation in their frequency depending on specific environmental conditions. The somatic and also the germ cells were characterized by a number of heteropycnotic nuclei and vacuolized chromosomes. Both the somatic and germ cells showed changes in the structural and functional organization of heterochromatin and this was particularly marked in the telomeric sectors of the chromosomes. The heterochromatin which is extremely sensitive to radioactivity appears to protect euchromatin from adverse environmental conditions

  5. Disseminated Cutaneous Larva Migrans

    Directory of Open Access Journals (Sweden)

    Karthikeyan Kaliaperumal

    2002-01-01

    Full Text Available A 30 year old male agricultural labourer presented with generalized itchy lesions over the back and extremities of 5 days duration. Cutaneous examination revealed multiple erythematous linear to serpentine lesions (numbering about 40 about 1-2 mm in width and ranging in length from 7 to 9 cm. The patient had eosinophilia and classical skin lesions, which responded very well to albendazole therapy. All these features supported the clinical diagnosis of dissenmintal cutaneous larva migrans.

  6. Lethal effects of abamectin on the aquatic organisms Daphnia similis, Chironomus xanthus and Danio rerio.

    Science.gov (United States)

    Novelli, Andréa; Vieira, Bruna Horvath; Cordeiro, Daniela; Cappelini, Luciana Teresa Dias; Vieira, Eny Maria; Espíndola, Evaldo Luiz Gaeta

    2012-01-01

    Abamectin is used as an acaricide and insecticide for fruits, vegetables and ornamental plants, as well as a parasiticide for animals. One of the major problems of applying pesticides to crops is the likelihood of contaminating aquatic ecosystems by drift or runoff. Therefore, toxicity tests in the laboratory are important tools to predict the effects of chemical substances in aquatic ecosystems. The aim of this study was to assess the potential hazards of abamectin to the freshwater biota and consequently the possible losses of ecological services in contaminated water bodies. For this purpose, we identified the toxicity of abamectin on daphnids, insects and fish. Abamectin was highly toxic, with an EC(50) 48 h for Daphnia similis of 5.1 ng L(-1), LC(50) 96 h for Chironomus xanthus of 2.67 μg L(-1) and LC(50) 48 h for Danio rerio of 33 μg L(-1). PMID:21955349

  7. ELISA detection of multixenobiotic resistance transporter induction in indigenous freshwater Chironomidae larvae (Diptera): A biomarker calibration step for in situ monitoring of xenobiotic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, X.; Saez, G.; Thiery, A. [Equipe ' Biomarqueurs and Bioindicateurs Environnementaux' , UMR-CNRS 6116 IMEP, Universite de Provence, 3 Place Victor Hugo, 13331 Marseille cedex 3 (France); Clot-Faybesse, O.; Guiraudie-Capraz, G. [' Neurobiologie Integrative et Adaptative' -UMR 6149, Universite de Provence, 3 Place Victor Hugo, 13331 Marseille cedex 3 (France); Bienboire-Frosini, C. [' Neurobiologie Integrative et Adaptative' -UMR 6149, Universite de Provence, 3 Place Victor Hugo, 13331 Marseille cedex 3 (France); Pherosynthese, Le Rieu Neuf, 84490 St Saturnin d' Apt (France); Martin, C. [Equipe ' Biomarqueurs and Bioindicateurs Environnementaux' , UMR-CNRS 6116 IMEP, UAPV, 33 rue Louis Pasteur, 84000 Avignon (France); De Jong, L. [Equipe ' Biomarqueurs and Bioindicateurs Environnementaux' , UMR-CNRS 6116 IMEP, Universite de Provence, 3 Place Victor Hugo, 13331 Marseille cedex 3 (France)], E-mail: laetitia.moreau@univ-provence.fr

    2008-06-15

    A new simple and sensitive method to distinguish chemically polluted from unpolluted situations in freshwater ecosystems is reported. For this purpose, Chironomus gr thumni larvae were collected from a polluted urban river downstream a sewage treatment plant. For the first time, ELISA assay was used to semi-quantify the multixenobiotic resistance transporters (MXR) in these small pertinent bioindicators. The use of samples immediately fixed in the field gives a delay to isolate larvae and allows multi-sampling along a longitudinal transect in a river at a given time. Results exhibit an induction of MXR proteins in larvae from the polluted river and a deinduction in larvae maintained 11 days in unpolluted water. They show new evidences to use midge larvae in biomonitoring environmental programs. They answer to first biomarker calibration steps for the ongoing development of MXR transporters as a detection tool of xenobiotic impacts on bioindicator invertebrates in their freshwater habitats. - Semi-quantification of midge larval MXR transporters by ELISA is a simple and sensitive method to detect chemically polluted situations in running freshwaters.

  8. ELISA detection of multixenobiotic resistance transporter induction in indigenous freshwater Chironomidae larvae (Diptera): A biomarker calibration step for in situ monitoring of xenobiotic exposure

    International Nuclear Information System (INIS)

    A new simple and sensitive method to distinguish chemically polluted from unpolluted situations in freshwater ecosystems is reported. For this purpose, Chironomus gr thumni larvae were collected from a polluted urban river downstream a sewage treatment plant. For the first time, ELISA assay was used to semi-quantify the multixenobiotic resistance transporters (MXR) in these small pertinent bioindicators. The use of samples immediately fixed in the field gives a delay to isolate larvae and allows multi-sampling along a longitudinal transect in a river at a given time. Results exhibit an induction of MXR proteins in larvae from the polluted river and a deinduction in larvae maintained 11 days in unpolluted water. They show new evidences to use midge larvae in biomonitoring environmental programs. They answer to first biomarker calibration steps for the ongoing development of MXR transporters as a detection tool of xenobiotic impacts on bioindicator invertebrates in their freshwater habitats. - Semi-quantification of midge larval MXR transporters by ELISA is a simple and sensitive method to detect chemically polluted situations in running freshwaters

  9. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination

    OpenAIRE

    Lagauzère, Sandra; Pischedda, Laura; Cuny, Philippe; Gilbert, Franck; Stora, Georges; Bonzom, Jean-Marc

    2009-01-01

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13–14%), and no temporal variation occurred afterwards. Within contaminated s...

  10. Adaptive response of Chironomus riparius populations exposed to uranium contaminated sediments during consecutive generations

    International Nuclear Information System (INIS)

    The intensity of selection on populations caused by polluted environment often exceeds which is caused by an unpolluted environment. Therefore, micro evolution can occur in response to this anthropic-directional force over a short period. In this context, this thesis focused on studying phenotypic changes in Chironomus riparius populations exposed during several consecutive generations to uranium-contaminated sediments. In laboratory-controlled conditions experiments were conducted with same origin populations exposed to a range of uranium concentration inducing toxic effects. Over eight-generations of exposure, life-history traits measures revealed micro evolution in exposed populations, including increase of adult reproductive success. Other experiments (acute toxicity test, common garden experiment) performed in parallel enabled to link these micro evolution with a tolerance induction, as a consequence of genetic adaptation. Nonetheless this adaptation also induced cost in terms of fitness and genetic diversity for pre-exposed populations. These results lead to the hypothesis of a selection by uranium that acted sequentially on populations. They also underline the need to better-understand the adaptive mechanisms to better assess the ecological consequences of chronic exposure of populations to a pollutant. (author)

  11. Ecotoxicological assessment of grey water treatment systems with Daphnia magna and Chironomus riparius.

    Science.gov (United States)

    Hernández Leal, L; Soeter, A M; Kools, S A E; Kraak, M H S; Parsons, J R; Temmink, H; Zeeman, G; Buisman, C J N

    2012-03-15

    In order to meet environmental quality criteria, grey water was treated in four different ways: 1) aerobic 2) anaerobic+aerobic 3) aerobic+activated carbon 4) aerobic+ozone. Since each treatment has its own specific advantages and disadvantages, the aim of this study was to compare the ecotoxicity of differently treated grey water using Chironomus riparius (96 h test) and Daphnia magna (48 h and 21d test) as test organisms. Grey water exhibited acute toxicity to both test organisms. The aerobic and combined anaerobic+aerobic treatment eliminated mortality in the acute tests, but growth of C. riparius was still affected by these two effluents. Post-treatment by ozone and activated carbon completely removed the acute toxicity from grey water. In the chronic toxicity test the combined anaerobic+aerobic treatment strongly affected D. magna population growth rate (47%), while the aerobic treatment had a small (9%) but significant effect. Hence, aerobic treatment is the best option for biological treatment of grey water, removing most of the toxic effects of grey water. If advanced treatment is required, the treatment with either ozone or GAC were shown to be very effective in complete removal of toxicity from grey water. PMID:22197265

  12. Microgavage of zebrafish larvae.

    Science.gov (United States)

    Cocchiaro, Jordan L; Rawls, John F

    2013-01-01

    The zebrafish has emerged as a powerful model organism for studying intestinal development(1-5), physiology(6-11), disease(12-16), and host-microbe interactions(17-25). Experimental approaches for studying intestinal biology often require the in vivo introduction of selected materials into the lumen of the intestine. In the larval zebrafish model, this is typically accomplished by immersing fish in a solution of the selected material, or by injection through the abdominal wall. Using the immersion method, it is difficult to accurately monitor or control the route or timing of material delivery to the intestine. For this reason, immersion exposure can cause unintended toxicity and other effects on extraintestinal tissues, limiting the potential range of material amounts that can be delivered into the intestine. Also, the amount of material ingested during immersion exposure can vary significantly between individual larvae(26). Although these problems are not encountered during direct injection through the abdominal wall, proper injection is difficult and causes tissue damage which could influence experimental results. We introduce a method for microgavage of zebrafish larvae. The goal of this method is to provide a safe, effective, and consistent way to deliver material directly to the lumen of the anterior intestine in larval zebrafish with controlled timing. Microgavage utilizes standard embryo microinjection and stereomicroscopy equipment common to most laboratories that perform zebrafish research. Once fish are properly positioned in methylcellulose, gavage can be performed quickly at a rate of approximately 7-10 fish/ min, and post-gavage survival approaches 100% depending on the gavaged material. We also show that microgavage can permit loading of the intestinal lumen with high concentrations of materials that are lethal to fish when exposed by immersion. To demonstrate the utility of this method, we present a fluorescent dextran microgavage assay that can be

  13. Larva therapy in wound management.

    OpenAIRE

    Courtenay, M; Church, J C; Ryan, T J

    2000-01-01

    The use of maggots for wound debridement has a long history and has lately gained ground in several countries. We collected prospective data to examine the current use of larva therapy (LT) in the UK. Quantitative information was collected on 70 patients treated in nine hospitals. LT is used primarily to treat leg ulcers and generally involves three applications of larvae at two to three day intervals. This method is judged effective in wound debridement and promotes the growth of granulation...

  14. Toxicity of sediment-associated pesticides to Chironomus dilutus and Hyalella azteca.

    Science.gov (United States)

    Ding, Yuping; Weston, Donald P; You, Jing; Rothert, Amanda K; Lydy, Michael J

    2011-07-01

    Two hundred sediment samples were collected and their toxicity evaluated to aquatic species in a previous study in the agriculturally dominated Central Valley of California, United States. Pyrethroid insecticides were the main contributors to the observed toxicity. However, mortality in approximately one third of the toxic samples could not be explained solely by the presence of pyrethroids in the matrices. Hundreds of pesticides are currently used in the Central Valley of California, but only a few dozen are analyzed in standard environmental monitoring. A significant amount of unexplained sediment toxicity may be due to pesticides that are in widespread use that but have not been routinely monitored in the environment, and even if some of them were, the concentrations harmful to aquatic organisms are unknown. In this study, toxicity thresholds for nine sediment-associated pesticides including abamectin, diazinon, dicofol, fenpropathrin, indoxacarb, methyl parathion, oxyfluorfen, propargite, and pyraclostrobin were established for two aquatic species, the midge Chironomus dilutus and the amphipod Hyalella azteca. For midges, the median lethal concentration (LC₅₀) of the pesticides ranged from 0.18 to 964 μg/g organic carbon (OC), with abamectin being the most toxic and propargite being the least toxic pesticide. A sublethal growth endpoint using average individual ash-free dry mass was also measured for the midges. The no-observable effect concentration values for growth ranged from 0.10 to 633 μg/g OC for the nine pesticides. For the amphipods, fenpropathrin was the most toxic, with an LC₅₀ of 1-2 μg/g OC. Abamectin, diazinon, and methyl parathion were all moderately toxic (LC₅₀s 2.8-26 μg/g OC). Dicofol, indoxacarb, oxyfluorfen, propargite, and pyraclostrobin were all relatively nontoxic, with LC₅₀s greater than the highest concentrations tested. The toxicity information collected in the present study will be helpful in decreasing the

  15. The effects of binary UV filter mixtures on the midge Chironomus riparius.

    Science.gov (United States)

    Ozáez, Irene; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2016-06-15

    Organic ultraviolet (UV) filters are used in a wide variety of products, including cosmetics, to prevent damage from UV light in tissues and industrial materials. Their extensive use has raised concerns about potential adverse effects in human health and aquatic ecosystems that accumulate these pollutants. To increase sun radiation protection, UV filters are commonly used in mixtures. Here, we studied the toxicity of binary mixtures of 4-methylbenzylidene camphor (4MBC), octyl-methoxycinnamate (OMC), and benzophenone-3 (BP-3), by evaluating the larval mortality of Chironomus riparius. Also molecular endpoints have been analyzed, including alterations in the expression levels of a gene related with the endocrine system (EcR, ecdysone receptor) and a gene related with the stress response (hsp70, heat shock protein 70). The results showed that the mortality caused by binary mixtures was similar to that observed for each compound alone; however, some differences in LC50 were observed between groups. Gene expression analysis showed that EcR mRNA levels increased in the presence of 0.1mg/L 4MBC but returned to normal levels after exposure to mixtures of 4MBC with 0.1, 1, and 10mg/L of BP-3 or OMC. In contrast, the hsp70 mRNA levels increased after exposure to the combinations tested of 4MBC and BP-3 or OMC mixtures. These data suggest that 4MBC, BP-3, and OMC may have antagonist effects on EcR gene transcription and a synergistic effect on hsp70 gene activation. This is the first experimental study to show the complex patterned effects of UV filter mixtures on invertebrates. The data suggest that the interactions within these chemicals mixtures are complex and show diverse effects on various endpoints. PMID:26971216

  16. Life cycle and production of chironomidae (diptera) in Biandantang, a typical macrophytic lake (Hubei, China)

    Science.gov (United States)

    Yun-Jun, Yan

    2000-09-01

    The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instarfrequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m2·a)) calculated by the size-frequency method for each species were: C. plumosus, 2.663; Chironomus sp., 1.161; Clinotanypus sp., 0.270; T. akamusi, 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2, and 4.4, respectively.

  17. LIFE CYCLE AND PRODUCTION OF CHIRONOMIDAE(DIPTERA) IN BIANDANTANG, A TYPICAL MACROPHYTIC LAKE (HUBEI, CHINA)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The life cycle and annual production of four dominant species of Chironomids (Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instar-frequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m2.a)) calculated by the size-frequency method for each species were: C. plumosus, 2.663; Chironomus sp.,1.161 ;Clinotanypus sp., 0.270; T. akamusi, 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2 and 4.4, respectively.

  18. Using artificial streams to assess the effects of metal-mining effluent on the life cycle of the freshwater midge (Chironomus tentans) in situ.

    Science.gov (United States)

    Hruska, Kimberly A; Dubé, Monique G

    2004-11-01

    In 2002, we developed an in situ life-cycle bioassay with Chironomus tentans in artificial streams to evaluate the effects of a complex metal mine effluent under ambient environmental conditions. The bioassay was tested in the field using effluent from the Copper Cliff Waste Water Treatment Plant at INCO (Sudbury, ON, Canada). Chironomus tentans were exposed throughout the life cycle to 45% Copper Cliff effluent, which is the average effluent concentration measured in Junction Creek (ON, Canada), the natural receiving environment. Chironomus tentans in the effluent treatment exhibited reduced survival (p = 0.001), reduced total emergence (p = 0.001), increased time-to-emergence (p = 0.001), and reduced hatching success (p = 0.001) relative to animals in the reference water treatment. Chironomus tentans in the effluent treatment were not significantly different from the reference in terms of growth, sex ratio, number of egg cases/female, and number of eggs/egg case. This research showed how a life-cycle bioassay could be used in situ to assess metal mine effluent effects on a benthic invertebrate. PMID:15559287

  19. Cutaneous larva migrans--a case report.

    Science.gov (United States)

    Padmavathy, L; Rao, L L

    2005-04-01

    Cutaneous larva migrans or creeping eruption is an uncommon parasitic skin infection caused by the filariform larvae of dog or cat hook worms. We report a case of larva migrans on the anterior abdominal wall, in a 52 year old lady, who did gardening as a hobby. PMID:15928447

  20. Cutaneous Larva Migrans - A Case Report

    OpenAIRE

    Padmavathy L; Rao L

    2005-01-01

    Cutaneous larva migrans or creeping eruption is an uncommon parasitic skin infection caused by the filariform larvae of dog or cat hook worms. We report a case of larva migrans on the anterior abdominal wall, in a 52 year old lady, who did gardening as a hobby.

  1. Cutaneous Larva Migrans - A Case Report

    Directory of Open Access Journals (Sweden)

    Padmavathy L

    2005-01-01

    Full Text Available Cutaneous larva migrans or creeping eruption is an uncommon parasitic skin infection caused by the filariform larvae of dog or cat hook worms. We report a case of larva migrans on the anterior abdominal wall, in a 52 year old lady, who did gardening as a hobby.

  2. Workbook on the Identification of Mosquito Larvae.

    Science.gov (United States)

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable public health workers identify larvae of some important North American mosquito species. The morphological features of larvae of the various genera and species are illustrated in a programed booklet, which also contains illustrated taxonomic keys to the larvae of 11 North American genera and to…

  3. Germ line transformation and in vivo labeling of nuclei in Diptera: report on Megaselia abdita (Phoridae) and Chironomus riparius (Chironomidae).

    Science.gov (United States)

    Caroti, Francesca; Urbansky, Silvia; Wosch, Maike; Lemke, Steffen

    2015-06-01

    To understand how and when developmental traits of the fruit fly Drosophila melanogaster originated during the course of insect evolution, similar traits are functionally studied in variably related satellite species. The experimental toolkit available for relevant fly models typically comprises gene expression and loss as well as gain-of-function analyses. Here, we extend the set of available molecular tools to piggyBac-based germ line transformation in two satellite fly models, Megaselia abdita and Chironomus riparius. As proof-of-concept application, we used a Gateway variant of the piggyBac transposon vector pBac{3xP3-eGFPafm} to generate a transgenic line that expresses His2Av-mCherry as fluorescent nuclear reporter ubiquitously in the gastrulating embryo of M. abdita. Our results open two phylogenetically important nodes of the insect order Diptera for advanced developmental evolutionary genetics. PMID:26044750

  4. An inducible HSP70 gene from the midge Chironomus dilutus: Characterization and transcription profile under environmental stress

    Science.gov (United States)

    Karouna-Renier, N. K.; Rao, K.R.

    2009-01-01

    In the present study, we identified and characterized an inducible heat shock protein 70 (HSP70) from the midge Chironomus dilutus and investigated the transcriptional profile of the gene under baseline and environmentally stressful conditions. Using real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), we observed increased expression of CD-HSP70-1 in response to both heat shock and copper stress. We also investigated the expression of this gene during midge development. All C. dilutus developmental stages expressed CD-HSP70-1 under normal conditions, although at extremely low levels. Phylogenetic analysis of the amino acid sequence demonstrated distinct clustering of this gene with inducible HSP70s from other insect species. ?? 2008 The Authors.

  5. Examining the joint toxicity of chlorpyrifos and atrazine in the aquatic species: Lepomis macrochirus, Pimephales promelas and Chironomus tentans

    Energy Technology Data Exchange (ETDEWEB)

    Tyler Mehler, W.; Schuler, Lance J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States); Lydy, Michael J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States)], E-mail: mlydy@siu.edu

    2008-03-15

    The joint toxicity of chlorpyrifos and atrazine was compared to that of chlorpyrifos alone to discern any greater than additive response using both acute toxicity testing and whole-body residue analysis. In addition, acetylcholinesterase (AChE) inhibition and biotransformation were investigated to evaluate the toxic mode of action of chlorpyrifos in the presence of atrazine. The joint toxicity of atrazine and chlorpyrifos exhibited no significant difference in Lepomis macrochirus compared to chlorpyrifos alone; while studies performed with Pimephales promelas and Chironomus tentans, did show significant differences. AChE activity and biotransformation showed no significant differences between the joint toxicity of atrazine and chlorpyrifos and that of chlorpyrifos alone. From the data collected, the combination of atrazine and chlorpyrifos pose little additional risk than that of chlorpyrifos alone to the tested fish species. - The joint toxicity between atrazine and chlorpyrifos caused greater than additive responses in invertebrates, but the interactions in vertebrates was less pronounced.

  6. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination.

    Science.gov (United States)

    Lagauzère, S; Pischedda, L; Cuny, P; Gilbert, F; Stora, G; Bonzom, J-M

    2009-04-01

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72h, the two invertebrate species significantly increased the DOU of sediments (13-14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants. PMID:19121883

  7. Isolamento de esporos de Paenibacillus larvae subsp. larvae no Brasil Detectionof Paenibacillus larvae subsp. larvae spores in Brazil

    Directory of Open Access Journals (Sweden)

    Dulce Maria Tocchetto Schuch

    2003-03-01

    Full Text Available Este trabalho objetivou detectar presença de esporos de Paenibacillus larvae subsp. larvae em produtos de um entreposto do interior do Estado do Rio Grande do Sul, a identificação de possíveis fontes de contaminação e a avaliação da possibilidade da transferência de esporos para colméias de apiários adjacentes a partir de produtos importados contaminados. Foram analisados mel e pólen importados disponíveis no entreposto, favo do ninho (crias, pólen e mel colhido de uma colméia sadia, mel estocado em um dos apiários e abelhas adultas. Os resultados foram positivosem relação ao mel e pólen importados, a três grupos de abelhas adultas e ao mel do favo.The objective of this work was to detect the presence of Paenibacillus larvae subsp. larvae spores in products from a warehouse located in Rio Grande do Sul State, Brazil, the identification of possible contamination sources, and the assessment of spores transference possibility from contaminated imported products from the warehouse to apiaries located in the surrounding area. Samples of imported pollen and bulk honey stocked in the warehouse, and honeycomb (brood, honey and pollen from a healthy hive, honey from one apiary and adult bees were analyzed. Imported honey and pollen, and three groups of adult bees and the honey collected from the honeycomb resulted positive.

  8. Radiosensitivity of spores of Paenibacillus larvae ssp. larvae in honey

    International Nuclear Information System (INIS)

    Irradiation, usually used in combination with other conventional methods of conservation, has been proven to be an efficient tool to ensure the safety of many types of foods by destroying pathogenic microorganisms and extending their shelf-lives. This work has investigated the efficacy of gamma irradiation to inactivate spores of the bacterium Paenibacillus larvae that causes the 'American foulbrood', a highly contagious disease still exotic in Brazil that kills bees and contaminates honey, preventing its commercialization and causing great economical losses. In this study, 60 g samples of two types of honey inoculated with 3.5x103 spores/mL of that bacterium were irradiated with doses of 0, 5, 7.5, 10, 12.5 and 15 kGy and counted. The analyses indicated a mean reduction of 97.5±0.7% in the number of viable spores exposed to 5 kGy. The application of doses of 7.5 kGy or higher yielded no viable spores above the detection threshold (10/mL). In addition the value of D10 (3.1±0.3 kGy) was estimated and the logarithm of the population of viable spores of Paenibacillus larvae subsp. larvae was determined as linear and quadratic polynomial functions of the radiation dose. The results indicated that the dose of 10 kGy could be insufficient to assure complete sterilization of honey in some cases while suggesting that 25 kGy would perform such task adequately. (author)

  9. Radiosensitivity of spores of Paenibacillus larvae ssp. larvae in honey

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Wanderley Mendes de [Ministerio da Agricultura, Pecuaria e Abastecimento, Rio de Janeiro, RJ (Brazil). Servico de Inspecao de Produtos de Origem Animal]. E-mail: sipa-rj@agricultura.gov.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito CTEx, Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear]. E-mail: vital@ctex.eb.br; Schuch, Dulce Maria Tocchetto [Ministerio da Agricultura, Pecuaria e Abastecimento, Porto Alegre, RS (Brazil)]. E-mail: micro-lara-rs@agricultura.gov.br

    2007-07-01

    Irradiation, usually used in combination with other conventional methods of conservation, has been proven to be an efficient tool to ensure the safety of many types of foods by destroying pathogenic microorganisms and extending their shelf-lives. This work has investigated the efficacy of gamma irradiation to inactivate spores of the bacterium Paenibacillus larvae that causes the 'American foulbrood', a highly contagious disease still exotic in Brazil that kills bees and contaminates honey, preventing its commercialization and causing great economical losses. In this study, 60 g samples of two types of honey inoculated with 3.5x10{sup 3} spores/mL of that bacterium were irradiated with doses of 0, 5, 7.5, 10, 12.5 and 15 kGy and counted. The analyses indicated a mean reduction of 97.5{+-}0.7% in the number of viable spores exposed to 5 kGy. The application of doses of 7.5 kGy or higher yielded no viable spores above the detection threshold (10/mL). In addition the value of D{sub 10} (3.1{+-}0.3 kGy) was estimated and the logarithm of the population of viable spores of Paenibacillus larvae subsp. larvae was determined as linear and quadratic polynomial functions of the radiation dose. The results indicated that the dose of 10 kGy could be insufficient to assure complete sterilization of honey in some cases while suggesting that 25 kGy would perform such task adequately. (author)

  10. Biology of Paenibacillus larvae, a deadly pathogen of honey bee larvae.

    Science.gov (United States)

    Ebeling, Julia; Knispel, Henriette; Hertlein, Gillian; Fünfhaus, Anne; Genersch, Elke

    2016-09-01

    The gram-positive bacterium Paenibacillus larvae is the etiological agent of American Foulbrood of honey bees, a notifiable disease in many countries. Hence, P. larvae can be considered as an entomopathogen of considerable relevance in veterinary medicine. P. larvae is a highly specialized pathogen with only one established host, the honey bee larva. No other natural environment supporting germination and proliferation of P. larvae is known. Over the last decade, tremendous progress in the understanding of P. larvae and its interactions with honey bee larvae at a molecular level has been made. In this review, we will present the recent highlights and developments in P. larvae research and discuss the impact of some of the findings in a broader context to demonstrate what we can learn from studying "exotic" pathogens. PMID:27394713

  11. Taste processing in Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Anthi A. Apostolopoulou

    2015-10-01

    Full Text Available The sense of taste allows animals to detect chemical substances in their environment to initiate appropriate behaviors: to find food or a mate, to avoid hostile environments and predators. Drosophila larvae are a promising model organism to study gustation. Their simple nervous system triggers stereotypic behavioral responses, and the coding of taste can be studied by genetic tools at the single cell level. This review briefly summarizes recent progress on how taste information is sensed and processed by larval cephalic and pharyngeal sense organs. The focus lies on several studies, which revealed cellular and molecular mechanisms required to process sugar, salt, and bitter substances.

  12. Metalloprotease production by Paenibacillus larvae during the infection of honeybee larvae.

    Science.gov (United States)

    Antúnez, Karina; Arredondo, Daniela; Anido, Matilde; Zunino, Pablo

    2011-05-01

    American foulbrood is a bacterial disease of worldwide distribution that affects larvae of the honeybee Apis mellifera. The causative agent is the Gram-positive, spore-forming bacterium Paenibacillus larvae. Several authors have proposed that P. larvae secretes metalloproteases that are involved in the larval degradation that occurs after infection. The aim of the present work was to evaluate the production of a metalloprotease by P. larvae during larval infection. First, the complete gene encoding a metalloprotease was identified in the P. larvae genome and its distribution was evaluated by PCR in a collection of P. larvae isolates from different geographical regions. Then, the complete gene was amplified, cloned and overexpressed, and the recombinant metalloprotease was purified and used to generate anti-metalloprotease antibodies. Metalloprotease production was evaluated by immunofluorescence and fluorescence in situ hybridization. The gene encoding a P. larvae metalloprotease was widely distributed in isolates from different geographical origins in Uruguay and Argentina. Metalloprotease was detected inside P. larvae vegetative cells, on the surface of P. larvae spores and secreted to the external growth medium. Its production was also confirmed in vivo, during the infection of honeybee larvae. This protein was able to hydrolyse milk proteins as described for P. larvae, suggesting that could be involved in larval degradation. This work contributes to the knowledge of the pathogenicity mechanisms of a bacterium of great economic significance and is one step in the characterization of potential P. larvae virulence factors. PMID:21330433

  13. Molecular Characterization of Ancylostoma braziliense Larvae in a Patient with Hookworm-Related Cutaneous Larva Migrans

    OpenAIRE

    Joncour, Alexandre Le; Lacour, Sandrine A.; Lecso, Gabriel; Regnier, Stéphanie; Guillot, Jacques; Caumes, Eric

    2012-01-01

    We report a case of hookworm-related cutaneous larva migrans diagnosed microscopically. Viable hookworm larvae were found by microscopic examination of a skin scraping from follicular lesions. Amplification and sequencing of the internal transcribed spacer 2 allowed the specific identification of the larvae as Ancylostoma braziliense.

  14. Workbook on Identification of Aedes Aegypti Larvae.

    Science.gov (United States)

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable yellow fever control workers to identify the larvae of "Aedes aegypti." The morphological features of mosquito larvae are illustrated in this partially programed text, and the distinguishing features of "A. aegypti" indicated. A glossary is included. (AL)

  15. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination

    Energy Technology Data Exchange (ETDEWEB)

    Lagauzere, S. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire (IRSN), DEI/SECRE/LRE, Cadarache 186, BP 3, F-13115 Cedex, Saint Paul Lez Durance (France)], E-mail: lagauzere@gmail.com; Pischedda, L.; Cuny, P. [Laboratoire de Microbiologie, Geochimie et Ecologie Marines, UMR 6117 CNRS/COM/Universite de la Mediterranee, Campus de Luminy, Case 901, F-13288 Cedex 09, Marseille (France); Gilbert, F. [EcoLab, Laboratoire d' Ecologie Fonctionnelle, UMR 5245 CNRS/INP/Universite Paul Sabatier, 29 Rue Jeanne Marvig, F-31055 Cedex 4, Toulouse (France); Stora, G. [Laboratoire de Microbiologie, Geochimie et Ecologie Marines, UMR 6117 CNRS/COM/Universite de la Mediterranee, Campus de Luminy, Case 901, F-13288 Cedex 09, Marseille (France); Bonzom, J.-M. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire (IRSN), DEI/SECRE/LRE, Cadarache 186, BP 3, F-13115 Cedex, Saint Paul Lez Durance (France)

    2009-04-15

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13-14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants. - This study highlights the ecological importance of bioturbation in metal-contaminated sediments.

  16. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination

    International Nuclear Information System (INIS)

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13-14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants. - This study highlights the ecological importance of bioturbation in metal-contaminated sediments

  17. A comparison of the sublethal and lethal toxicity of four pesticides in Hyalella azteca and Chironomus dilutus.

    Science.gov (United States)

    Hasenbein, Simone; Connon, Richard E; Lawler, Sharon P; Geist, Juergen

    2015-08-01

    Laboratory toxicity testing is the primary tool used for surface water environmental risk assessment; however, there are critical information gaps regarding the sublethal effects of pesticides. In 10-day exposures, we assessed the lethal and sublethal (motility and growth) toxicities of four commonly used pesticides, bifenthrin, permethrin, cyfluthrin, and chlorpyrifos, on two freshwater invertebrates, Chironomus dilutus and Hyalella azteca. Pyrethroids were more toxic than the organophosphate chlorpyrifos in both species. Bifenthrin was most toxic to H. azteca survival and growth. Cyfluthrin was most toxic to C. dilutus. However, cyfluthrin had the greatest effect on motility on both H. azteca and C. dilutus. The evaluated concentrations of chlorpyrifos did not affect C. dilutus motility or growth, but significantly impacted H. azteca growth. Motility served as the most sensitive endpoint in assessing sublethal effects at low concentrations for both species, while growth was a good indicator of toxicity for all four pesticides for H. azteca. The integration of sublethal endpoints in ambient water monitoring and pesticide regulation efforts could improve identification of low-level pesticide concentrations that may eventually cause negative effects on food webs and community structure in aquatic environments. PMID:25804662

  18. Support for the evolutionary speed hypothesis from intraspecific population genetic data in the non-biting midge Chironomus riparius.

    Science.gov (United States)

    Oppold, Ann-Marie; Pedrosa, João A M; Bálint, Miklós; Diogo, João B; Ilkova, Julia; Pestana, João L T; Pfenninger, Markus

    2016-02-24

    The evolutionary speed hypothesis (ESH) proposes a causal mechanism for the latitudinal diversity gradient. The central idea of the ESH is that warmer temperatures lead to shorter generation times and increased mutation rates. On an absolute time scale, both should lead to an acceleration of selection and drift. Based on the ESH, we developed predictions regarding the distribution of intraspecific genetic diversity: populations of ectothermic species with more generations per year owing to warmer ambient temperatures should be more differentiated from each other, accumulate more mutations and show evidence for increased mutation rates compared with populations in colder regions. We used the multivoltine insect species Chironomus riparius to test these predictions with cytochrome oxidase I (COI) sequence data and found that populations from warmer regions are indeed significantly more differentiated and have significantly more derived haplotypes than populations from colder regions. We also found a significant correlation of the annual mean temperature with the population mutation parameter θ that serves as a proxy for the per generation mutation rate under certain assumptions. This pattern could be corroborated with two nuclear loci. Overall, our results support the ESH and indicate that the thermal regime experienced may be crucially driving the evolution of ectotherms and may thus ultimately govern their speciation rate. PMID:26888029

  19. Effects of anti-C23 (nucleolin) antibody on transcription of ribosomal DNA in Chironomus salivary gland cells

    Energy Technology Data Exchange (ETDEWEB)

    Egyhazi, E.; Pigon, A. (Karolinska Institutet, Stockholm (Sweden)); Chang, Jinhong; Ghaffari, S.H.; Dreesen, T.D.; Wellman, S.E.; Case, S.T.; Olson, M.O.J. (Univ. of Mississippi Medical Center, Jackson (USA))

    1988-10-01

    Protein C23 (also called nucleolin or 100-kDa nucleolar protein) is a major nucleolar phosphoprotein involved in ribosome biogenesis. To determine the effects of protein C23 on preribosomal RNA (pre-rRNA) synthesis anti-C23 antiserum was microinjected into nuclei of Chironomus tentans salivary glands. Transcription was measured by incubation of the glands with {sup 32}P-labeled RNA precursors followed by microdissection of nucleoli, RNA extraction, and electrophoretic analyses. Injection of the anti-C23 antibody caused a 2- to 3.5-fold stimulation of {sup 32}P incorporation into 38 S pre-rRNA. No stimulation was observed in salivary glands injected with preimmune serum or antiserum preabsorbed with protein C23. The stimulatory effect was selective for pre-rRNA as indicated by the lack of stimulation of {sup 32}P incorporation into extranucleolar RNA. Injection of the antiserum produced little or no effect on pre-RNA processing as measured by the relative amounts of {sup 32}P-labeled intermediate cleavage products of pre-rRNA in stimulated versus control glands. These results suggest that protein C23 not only is involved in ribosome assembly but also plays a role in regulating the transcription of the preribosomal RNA.

  20. Effects of anti-C23 (nucleolin) antibody on transcription of ribosomal DNA in Chironomus salivary gland cells

    International Nuclear Information System (INIS)

    Protein C23 (also called nucleolin or 100-kDa nucleolar protein) is a major nucleolar phosphoprotein involved in ribosome biogenesis. To determine the effects of protein C23 on preribosomal RNA (pre-rRNA) synthesis anti-C23 antiserum was microinjected into nuclei of Chironomus tentans salivary glands. Transcription was measured by incubation of the glands with 32P-labeled RNA precursors followed by microdissection of nucleoli, RNA extraction, and electrophoretic analyses. Injection of the anti-C23 antibody caused a 2- to 3.5-fold stimulation of 32P incorporation into 38 S pre-rRNA. No stimulation was observed in salivary glands injected with preimmune serum or antiserum preabsorbed with protein C23. The stimulatory effect was selective for pre-rRNA as indicated by the lack of stimulation of 32P incorporation into extranucleolar RNA. Injection of the antiserum produced little or no effect on pre-RNA processing as measured by the relative amounts of 32P-labeled intermediate cleavage products of pre-rRNA in stimulated versus control glands. These results suggest that protein C23 not only is involved in ribosome assembly but also plays a role in regulating the transcription of the preribosomal RNA

  1. Cytogenetic study of natural chironomini (diptera, chiromedae) populations from open water bodies of former Semipalatinsk test site

    International Nuclear Information System (INIS)

    In the paper genetic variability of natural population of chironomidae inhabiting in waters on the territory of Semipalatinsk test site (STS) is studied. Ten Chironomini species of Chironomidae subfamily and one species of Tanypodinae subfamily were identified using cyto-taxonomic methods of analysis. Cytophotomap of polythene chromosomes of salivary glands were established for four species: Glyptotendipes salinus, Captochironomus setivalva, Camptochriomonus tentas and Chironomus plumosus. For the first time a new previously unknown species of Chironomus gender, and namely C, genelenus 1. sp. n. was described and a cytophotomap of its polythene chromosomes was established. A detailed quantative and qualitative analysis of chromosome polymorphism was carried out and the spectrum and frequency of the disk sequences and genotypic combination were identified. New evidence on change in the polythene chromosomes structure were revealed in certain Chironomini species dwelling in the radioactively contaminated water bodies of STS: rare, unique disk sequences of chromosomes were found, a series of specific homo zygote and heterozygote inversions were observed, which evidently resulted from long-term adaptive selection under conditions of the chronic ionizing radiation. Increase of in frequency of structural mutations of chromosomes was found in mitotic cells of imago disk of Chironomini larvae is revealed. This increase indicates that at the STS many population of benthos organisms are directly affected by the ionizing radiation

  2. Directional flow sensing by passively stable larvae.

    Science.gov (United States)

    Fuchs, Heidi L; Christman, Adam J; Gerbi, Gregory P; Hunter, Elias J; Diez, F Javier

    2015-09-01

    Mollusk larvae have a stable, velum-up orientation that may influence how they sense and react to hydrodynamic signals applied in different directions. Directional sensing abilities and responses could affect how a larva interacts with anisotropic fluid motions, including those in feeding currents and in boundary layers encountered during settlement. Oyster larvae (Crassostrea virginica) were exposed to simple shear in a Couette device and to solid-body rotation in a single rotating cylinder. Both devices were operated in two different orientations, one with the axis of rotation parallel to the gravity vector, and one with the axis perpendicular. Larvae and flow were observed simultaneously with near-infrared particle-image velocimetry, and behavior was quantified as a response to strain rate, vorticity and centripetal acceleration. Only flows rotating about a horizontal axis elicited the diving response observed previously for oyster larvae in turbulence. The results provide strong evidence that the turbulence-sensing mechanism relies on gravity-detecting organs (statocysts) rather than mechanosensors (cilia). Flow sensing with statocysts sets oyster larvae apart from zooplankters such as copepods and protists that use external mechanosensors in sensing spatial velocity gradients generated by prey or predators. Sensing flow-induced changes in orientation, rather than flow deformation, would enable more efficient control of vertical movements. Statocysts provide larvae with a mechanism of maintaining their upward swimming when rotated by vortices and initiating dives toward the seabed in response to the strong turbulence associated with adult habitats. PMID:26333930

  3. Single stimulus learning in zebrafish larvae

    OpenAIRE

    O’Neale, Ashley; Ellis, Joseph; Creton, Robbert; Colwill, Ruth M.

    2013-01-01

    Learning about a moving visual stimulus was examined in zebrafish larvae using an automated imaging system and a t1-t2 design. In three experiments, zebrafish larvae were exposed to one of two inputs at t1 (either a gray bouncing disk or an identical but stationary disk) followed by a common test at t2 (the gray bouncing disk). Using 7 days post-fertilization (dpf) larvae and 12 stimulus exposures, Experiment 1 established that these different treatments produced differential responding to th...

  4. Cutaneous Larva Migrans in Early Infancy.

    Science.gov (United States)

    Siddalingappa, Karjigi; Murthy, Sambasiviah Chidambara; Herakal, Kallappa; Kusuma, Marganahalli Ramachandra

    2015-01-01

    Cutaneous larva migrans or creeping eruptions is a cutaneous dermatosis caused by hookworm larvae, Ancylostoma braziliense. A 2-month-old female child presented with a progressive rash over the left buttock of 4 days duration. Cutaneous examination showed an urticarial papule progressing to erythematous, tortuous, thread-like tract extending a few centimeters from papule over the left gluteal region. A clinical diagnosis of cutaneous larva migrans was considered. Treatment with albendazole led to complete resolution, confirming the diagnosis. This is to the best of our knowledge, the youngest age at which this condition is being reported. PMID:26538729

  5. Habitat selection by emperor fish larvae

    OpenAIRE

    Nakamura, Y; Shibuno, T.; Lecchini, David; Watanabe, Y.

    2009-01-01

    One of the great puzzles of coral reef fish ecology is how pelagic larvae locate the habitat in which they settle. The present study explored whether offshore emperor fish (Lethrinidae) larvae selected a specific reef and/or habitat at settlement. Although older juveniles are known to use back-reef seagrass beds as a potential nursery habitat, information is scarce regarding pre-settlement larvae. Using light traps anchored on the reef slopes at seagrass-replete and seagrass-free reefs (lshig...

  6. The Balbiani ring 2 gene in Chironomus tentans is built from two types of tandemly arranged major repeat units with a common evolutionary origin

    OpenAIRE

    Wieslander, L.; Lendahl, U.

    1983-01-01

    The internal structure of the 37 kb long Balbiani ring 2 (BR 2) gene in Chironomus tentans has been studied by analysis of a collection of cloned cDNA sequences and in genomic Southern blot analysis with the cDNA sequences used as probes. The BR 2 gene contains two types of tandemly arranged major repeat units ˜200 bp long, represented in our study by the pCt 7 and the pCt 63 cDNA inserts. The pCt 7 major repeat units are arranged in one or possibly a few blocks and cover ˜10 kb of the gene; ...

  7. TIME management by medicinal larvae.

    Science.gov (United States)

    Pritchard, David I; Čeřovský, Václav; Nigam, Yamni; Pickles, Samantha F; Cazander, Gwendolyn; Nibbering, Peter H; Bültemann, Anke; Jung, Wilhelm

    2016-08-01

    Wound bed preparation (WBP) is an integral part of the care programme for chronic wounds. The acronym TIME is used in the context of WBP and describes four barriers to healing in chronic wounds; namely, dead Tissue, Infection and inflammation, Moisture imbalance and a non-migrating Edge. Larval debridement therapy (LDT) stems from observations that larvae of the blowfly Lucilia sericata clean wounds of debris. Subsequent clinical studies have proven debriding efficacy, which is likely to occur as a result of enzymatically active alimentary products released by the insect. The antimicrobial, anti-inflammatory and wound healing activities of LDT have also been investigated, predominantly in a pre-clinical context. This review summarises the findings of investigations into the molecular mechanisms of LDT and places these in context with the clinical concept of WBP and TIME. It is clear from these findings that biotherapy with L. sericata conforms with TIME, through the enzymatic removal of dead tissue and its associated biofilm, coupled with the secretion of defined antimicrobial peptides. This biotherapeutic impact on the wound serves to reduce inflammation, with an associated capacity for an indirect effect on moisture imbalance. Furthermore, larval serine proteinases have the capacity to alter fibroblast behaviour in a manner conducive to the formation of granulation tissue. PMID:26179750

  8. Visceral larva migrans caused by Trichuris vulpis.

    OpenAIRE

    Sakano, T; Hamamoto, K.; Kobayashi, Y; Sakata, Y; Tsuji, M.; Usui, T.

    1980-01-01

    Two brothers with visceral larva migrans caused by Trichuris vulpis were diagnosed after they had been investigated for an eosinophilia. Both patients were almost asymptomatic. The diagnosis of visceral larva migrans was based on the results of immunoelectrophoretic studies and no liver biopsy was performed. After administration of thiabendazole, the number of eosinophils and serum total IgE levels gradually decreased, and the patients have remained well.

  9. Overexpression of long non-coding RNAs following exposure to xenobiotics in the aquatic midge Chironomus riparius

    International Nuclear Information System (INIS)

    Non-coding RNAs (ncRNAs) represent an important transcriptional output of eukaryotic genomes. In addition to their functional relevance as housekeeping and regulatory elements, recent studies have suggested their involvement in rather unexpected cellular functions. The aim of this work was to analyse the transcriptional behaviour of non-coding RNAs in the toxic response to pollutants in Chironomus riparius, a reference organism in aquatic toxicology. Three well-characterized long non-coding sequences were studied: telomeric repeats, Cla repetitive elements and the SINE CTRT1. Transcription levels were evaluated by RT-PCR after 24-h exposures to three current aquatic contaminants: bisphenol A (BPA), benzyl butyl phthalate (BBP) and the heavy metal cadmium (Cd). Upregulation of telomeric transcripts was found after BPA treatments. Moreover, BPA significantly activated Cla transcription, which also appeared to be increased by cadmium, whereas BBP did not affect the transcription levels of these sequences. Transcription of SINE CTRT1 was not altered by any of the chemicals tested. These data are discussed in the light of previous studies that have shown a response by long ncRNAS (lncRNAs) to cellular stressors, indicating a relationship with environmental stimuli. Our results demonstrated for the first time the ability of bisphenol A to activate non-coding sequences mainly located at telomeres and centromeres. Overall, this study provides evidence that xenobiotics can induce specific responses in ncRNAs derived from repetitive sequences that could be relevant in the toxic response, and also suggests that ncRNAs could represent a novel class of potential biomarkers in toxicological assessment.

  10. Overexpression of long non-coding RNAs following exposure to xenobiotics in the aquatic midge Chironomus riparius

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Guitarte, Jose-Luis, E-mail: jlmartinez@ccia.uned.es [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain); Planello, Rosario; Morcillo, Gloria [Grupo de Biologia y Toxicologia Ambiental, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, UNED, Senda del Rey 9, 28040 Madrid (Spain)

    2012-04-15

    Non-coding RNAs (ncRNAs) represent an important transcriptional output of eukaryotic genomes. In addition to their functional relevance as housekeeping and regulatory elements, recent studies have suggested their involvement in rather unexpected cellular functions. The aim of this work was to analyse the transcriptional behaviour of non-coding RNAs in the toxic response to pollutants in Chironomus riparius, a reference organism in aquatic toxicology. Three well-characterized long non-coding sequences were studied: telomeric repeats, Cla repetitive elements and the SINE CTRT1. Transcription levels were evaluated by RT-PCR after 24-h exposures to three current aquatic contaminants: bisphenol A (BPA), benzyl butyl phthalate (BBP) and the heavy metal cadmium (Cd). Upregulation of telomeric transcripts was found after BPA treatments. Moreover, BPA significantly activated Cla transcription, which also appeared to be increased by cadmium, whereas BBP did not affect the transcription levels of these sequences. Transcription of SINE CTRT1 was not altered by any of the chemicals tested. These data are discussed in the light of previous studies that have shown a response by long ncRNAS (lncRNAs) to cellular stressors, indicating a relationship with environmental stimuli. Our results demonstrated for the first time the ability of bisphenol A to activate non-coding sequences mainly located at telomeres and centromeres. Overall, this study provides evidence that xenobiotics can induce specific responses in ncRNAs derived from repetitive sequences that could be relevant in the toxic response, and also suggests that ncRNAs could represent a novel class of potential biomarkers in toxicological assessment.

  11. Coral larvae move toward reef sounds.

    Directory of Open Access Journals (Sweden)

    Mark J A Vermeij

    Full Text Available Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency.

  12. Attraction to and learning from social cues in fruitfly larvae

    OpenAIRE

    Durisko, Zachary; Dukas, Reuven

    2013-01-01

    We examined the use of social information in fruitfly larvae, which represent an ideal model system owing to their robust learning abilities, small number of neurons and well-studied neurogenetics. Focal larvae showed attraction to the distinct odour emanating from food occupied by other larvae. In controlled learning experiments, focal larvae preferred novel odours previously paired with food occupied by other larvae over novel odours previously paired with unoccupied food. When we gave grou...

  13. Late presentation of cutaneous larva migrans: a case report

    OpenAIRE

    Archer, Michael

    2009-01-01

    Introduction Cutaneous larva migrans is caused by infection with hookworm larvae in tropical and sub-tropical areas. A history of recent travel to the tropics is usually elicited. Case presentation A case of cutaneous larva migrans is described in which symptoms did not appear until five months after travel to Tanzania. Conclusion Although the lesion of cutaneous larva migrans may appear immediately, the larvae may lie dormant for many months and presentation may therefore occur a long time a...

  14. FRAGMENTATION OF POLYTENE CHROMOSOMES OF CHIRONOMUS STRIATIPENNIS (KIEFFER AS A MARK OF HEAVY METAL TOXICITY IN AQUATIC HABITATS

    Directory of Open Access Journals (Sweden)

    A. MAZUMDAR

    2013-01-01

    Full Text Available The adults of Chironomids are though terrestrial, but in immature stages they pass their days in water. In aquaticbodies the flies at their larval stages live about 18-20 days and any incompatible situation in the habitats affectsgrowth and development of the larvae. A study on the polytene chromosomes of the salivary gland cells of thelarvae of C. striatipennis indicated that high level of toxicity due to heavy metals in the habitats led to fragmentationof their polytene chromosomes. Culturing of the larvae of this species in the laboratory with 30 mg/Kg of Cd withsoil in the culture bed exhibited fragmentation of their polytene chromosomes in certain cases. In this toxicityimpact the fourth polytene chromosome appeared to be more affected. Hence, a variation of response of differentchromosomes of the fly to toxicity may be suggested.

  15. Effect of gamma rays on the larvae of Rhipicephalus bursa

    International Nuclear Information System (INIS)

    Rhipicephalus bursa larvae were exposed to a single acute gamma-irradiation from cobalt 60 source in doses from 0.5 to 40 kiloroentgen (kr). Doses higher than 20 kr rilled the larvae, lower than 10 kr produced disturbances in tick development, dependent on radiation; larvae irradiated with 2 to 3 kr started sucking blood as larvae ordinarily do, but could not undergo metamorphosis; larvae irradiated with lower doses (0.5 and 1 kr) had a prolonged metamorphosis, the onset of oviposition was delayed and the percentage of hatched second generation larvae was reduced. (A.B.)

  16. Dispersal strategies in sponge larvae: integrating the life history of larvae and the hydrologic component.

    Science.gov (United States)

    Mariani, Simone; Uriz, María-J; Turon, Xavier; Alcoverro, Teresa

    2006-08-01

    While known to be uniformly non-feeding, short-lived, and potentially short dispersing, sponge larvae display different behaviours (swimming ability and taxis). Our aim was to show whether sponge larvae with different behaviours exhibit different dispersal strategies under variable intensity of water movements. We first assessed the distribution of larvae of six taxa: Dictyoceratida spp., Dysidea avara, Crambe crambe, Phorbas tenacior, Scopalina lophyropoda, and Cliona viridis, collected through plankton sampling, and the abundance of the corresponding adult sponges across three hard bottom communities and a sandy bottom from a north-west Mediterranean rocky shore. We then tested adult-larvae couplings (abundance of larvae vs abundance of adults) under increasing levels of water movements (surge) to assess the importance of this environmental factor in driving differences in dispersal strategies. Adults of Dictyoceratida spp., D. avara, and P. tenacior were most abundant in semi-dark caves (SDC), C. crambe and C. viridis in communities of sciaphilic algae (SA), whereas the distribution of S. lophyropoda was extremely patchy, being present almost only in the SA community of one of the five stations studied. Larvae of Dictyoceratida spp. and P. tenacior were more abundant in the SDC, whereas D. avara and C. crambe were homogeneously distributed across the communities. The larvae of C. viridis were more abundant in the SA communities and the S. lophyropoda larvae were mostly present in one station and one community (SA). Increased water movement did not modify the adult-larvae coupling for Dictyoceratida spp., D. avara, and C. crambe, whereas it broke up the positive association for P. tenacior and to some extent S. lophyropoda. For C. viridis, possible variability in adult-larvae coupling was not tested because the larvae were collected on only one day under calm sea conditions. We confirm that efficient-swimming larvae with some cue response can actively counteract

  17. CalCOFI Larvae Counts, Scientific Names TF to U

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring...

  18. CalCOFI Larvae Counts, Scientific Names SB to SC

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring...

  19. Bothid larvae (Pleuronectiformes-Pisces) of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    the Indian Ocean, their regional, seasonal as well as diurnal variations. Engyprosopon grandisquamis dominated contributing to 23.2% of the total larvae. Numerically the incidence of bothid larvae suggested a uniform pattern of distribution during the two...

  20. CalCOFI Larvae Counts, Scientific Names CI to CO

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring...

  1. ФАУНА, КАРИОТИПЫ И ЭКОЛОГИЯ КОМАРОВ-ЗВОНЦОВ РОДА CHIRONOMUS MEIGEN, 1803 (DIPTERA, CHIRONOMIDAE) ТИСО-САМШИТОВОЙ РОЩИ (СЕВЕРО-ЗАПАДНЫЙ КАВКАЗ)

    OpenAIRE

    Кармоков, Мухамед; Полуконова, Наталья

    2014-01-01

    Data on fauna, features of ecology and karyotypes of non-biting midges from genus Chironomus Meigen, 1803 (Diptera, Chironomidae) at temporary reservoirs of upper courses of Sukanskiy gorge (Central Caucasus, northern macroslope) are submitted. Three species of chironomus are found: Chironomus : Ch. piger Strenzke, 1959, Ch. dorsalis Meigen, 1818 и Ch. riparius Meigen, 1804. All species are widespread and typical inhabitants of temporary reservoirs. Chromosomal reorganizations it is not revea...

  2. Evolution of foraging behavior in Drosophilid larvae

    Science.gov (United States)

    Rivera-Alba, Marta; Kabra, Mayank; Branson, Kristin; Mirth, Christen

    2015-03-01

    Drosophilids, like other insects, go through a larval phase before metamorphosing into adults. Larvae increase their body weight by several orders of magnitude in a few days. We therefore hypothesized that foraging behavior is under strong evolutionary pressure to best fit the larval environment. To test our hypothesis we used a multidisciplinary approach to analyze foraging behavior across species and larval stages. First, we recorded several videos of larvae foraging for each of 47 Drosophilid species. Then, using a supervised machine learning approach, we automatically annotated the video collection for the foraging sub-behaviors, including crawling, turning, head casting or burrowing. We also computed over 100 features to describe the posture and dynamics of each animal in each video frame. From these data, we fit models to the behavior of each species. The models each had the same parametric form, but differed in the exact parameters. By simulating larva behavior in virtual arenas we can infer which properties of the environments are better for each species. Comparisons between these inferred environments and the actual environments where these animals live will give us a deeper understanding about the evolution of foraging behavior in Drosophilid larvae.

  3. The Identification of Congeners and Aliens by Drosophila Larvae

    OpenAIRE

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species....

  4. Image Enhancement for Tracking the Translucent Larvae of Drosophila melanogaster

    OpenAIRE

    Khurana, Sukant; Li, Wen-Ke; Atkinson, Nigel S.

    2010-01-01

    Drosophila melanogaster larvae are model systems for studies of development, synaptic transmission, sensory physiology, locomotion, drug discovery, and learning and memory. A detailed behavioral understanding of larvae can advance all these fields of neuroscience. Automated tracking can expand fine-grained behavioral analysis, yet its full potential remains to be implemented for the larvae. All published methods are unable to track the larvae near high contrast objects, including the petri-di...

  5. ISOLASI BACILLUS THURINGIENSIS DARI LARVA DAN PENGUJIAN PATOGENISITASNYA TERHADAP LARVA NYAMUK VEKTOR

    Directory of Open Access Journals (Sweden)

    Blondine Ch. P.

    2012-09-01

    Full Text Available A study to evaluate pathogenic organisms as cause of mosquito larvae death was conducted at Wonokerto and Pabelan villages, Salatiga Luar Kota subdistrict, Semarang regency in Central Java from May 1991 through December 1991. Bacterial isolation from dead larvae showed that 31 B. thuringicnsis isolates were obtained from 31 larvae samples collected from 2 location e.g Wonokerto village (3 samples, Pabelan village (28 samples. Nineteen isolates (61,3% showed a pathogenicity of more than 50% to third toward instar larvae of Aedes aegypti and Culex quinquefasciatus respectively 24 hours after exposure. This study shows the possible use of B. thuringiensis for biologic control of mosquitoes which can act as vectors for human diseases.

  6. Ecological and Genetic Relationship of Chironomus circumdatus (Diptera, Chironomidae From Mitochondrial Cytochrome Oxidase Subunit I in Chiang Mai Province, Northern Thailand

    Directory of Open Access Journals (Sweden)

    W. Roongruangwongse

    2012-04-01

    Full Text Available This study provides means for more accurate identification of Chironomus circumdatus species for environmental and ecological management by Population of C. circumdatus (86 individuals and water samples were collected from three different sites of Chiang Mai Province, Thailand. Specimens of Einfeldia sp. were used as an initial out group. The genetic relationship of C. circumdatus specimens from these sources was determined by using DNA sequence analysis of partial mtDNA gene’s Cytochrome Oxidase Subunit I (COI. Analysis of genetic distance on the basis of sequence difference for COI mitochondrial gene showed very little genetic difference and the data from phylogenetic analysis revealed a very large genetic difference among all populations of this species for the COI gene sequences. In addition, NJ tree was related to with physicochemical parameters of the water samples.

  7. Nutritional condition and vertical distribution of Baltic cod larvae

    DEFF Research Database (Denmark)

    Grønkjær, P.; Clemmesen, C.; St. John, Michael

    lest this hypothesis, Baltic cod larvae were sampled during the spawning seasons of 1994 and 1995 with depth-resolving multiple opening/closing nets. Each larva was aged by otolith readings and its RNA/DNA ratio was determined as a measure of nutritional condition. The RNA/DNA ratios of these larvae...

  8. Complete Genome Sequence of Paenibacillus larvae MEX14, Isolated from Honey Bee Larvae from the Xochimilco Quarter in Mexico City.

    Science.gov (United States)

    Peréz de la Rosa, D; Pérez de la Rosa, J J; Cossio-Bayugar, R; Miranda-Miranda, E; Lozano, L; Bravo-Díaz, M A; Rocha-Martínez, M K; Sachman-Ruiz, B

    2015-01-01

    Paenibacillus larvae strain MEX14 is a facultative anaerobic endospore-forming bacterium that infects Apis mellifera larvae. Strain MEX14 was isolated from domestic bee larvae collected in a backyard in Mexico City. The estimated genome size was determined to be 4.18 Mb, and it harbors 4,806 protein coding genes (CDSs). PMID:26316636

  9. Larva of Palaemnema brasiliensis Machado (Odonata: Platystictidae), from Amazonas, Brazil.

    Science.gov (United States)

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-01-01

    The larva of Palaemnema brasiliensis Machado, 2009 is described and illustrated based on last-instar larvae and exuviae of reared larvae collected in a blackwater stream in Barcelos and Presidente Figueiredo municipalities, Amazonas state, Brazil. The larva of P. brasiliensis can be distinguished from the two South American species of the genus with described larvae (P. clementia Selys and P. mutans Calvert), mainly by presence of a single obtuse cusp on the labial palp, the presence and configuration of setae in the caudal lamellae, and the proportional length of terminal filaments of the caudal lamellae. The family is recorded here for the first time in Brazilian state of Amazonas. PMID:27395963

  10. Larvas de Chironomidae arvas (Diptera da planície de inundação do alto rio Paraná: distribuição e composição em diferentes ambientes e períodos hidrológicos = Chironomidae larvae (Diptera from the upper Paraná river floodplain: distribution and composition in different environments and hydrological periods

    Directory of Open Access Journals (Sweden)

    Gisele Cristina Rosin

    2007-01-01

    Full Text Available O presente estudo teve por objetivos, identificar possíveis diferenças na estrutura da comunidade de larvas de Chironomidae em quatro ambientes da planície de inundação do alto rio Paraná com diferentes características e analisar a influência dos fatores abióticos e das variações do nível hidrométrico sobre a comunidade. As coletas foram realizadas em março e setembro de 2003. Em cada um dos 12 pontos coletados foram realizadas quatro amostragens: três para análise biológica e uma para análise sedimentológica. O material biológico foi lavado em conjunto de peneiras com malhas de abertura 2, 1 e 0,2 mm e fixado em álcool 70%. As larvas de Chironomidae foram identificadas até a categoria de gênero. Foram encontradas 1478larvas de Chironomidae pertencentes a 19 gêneros. Polypedilum, Tanytarsus e Chironomus foram registrados em todos os ambientes. As maiores densidades e diversidade de Chironomidae foram registradas nos períodos de águas baixas, especialmente em ambientes lênticos. Avariação da densidade, dominância e diversidade de Chironomidae entre as duas coletas foi influenciada, principalmente, pelo ciclo hidrológico e pelo oxigênio dissolvido, enquanto que a variação espacial esteve associada ao tipo de sedimento, porcentagem de matéria orgânica e a presença ou ausência de macrófitas aquáticas.The present study had the aim to identify possible differences in the community structure of Chironomidae larvae in four different environments of the upper Paraná river floodplain with different characteristics and to analyze the influence of abiotic factors and variations in the hydrometric level of the community. Samplings were carried out in March and September, 2003. Four samplings were taken from each of the 12 collecting points: three for biological analysis and one for sediment analysis. Biological contents were washed with the aid of a system with 2.0; 1.0 and 0.2 mm sieves. Chironomidae larvae were

  11. Larvas de Chironomidae arvas (Diptera da planície de inundação do alto rio Paraná: distribuição e composição em diferentes ambientes e períodos hidrológicos - DOI: 10.4025/actascibiolsci.v29i1.127 Chironomidae larvae (Diptera from the upper Paraná river floodplain: distribution and composition in different environments and hydrological periods

    Directory of Open Access Journals (Sweden)

    Alice Michiyo Takeda

    2007-11-01

    Full Text Available O presente estudo teve por objetivos, identificar possíveis diferenças na estrutura da comunidade de larvas de Chironomidae em quatro ambientes da planície de inundação do alto rio Paraná com diferentes características e analisar a influência dos fatores abióticos e das variações do nível hidrométrico sobre a comunidade. As coletas foram realizadas em março e setembro de 2003. Em cada um dos 12 pontos coletados foram realizadas quatro amostragens: três para análise biológica e uma para análise sedimentológica. O material biológico foi lavado em conjunto de peneiras com malhas de abertura 2, 1 e 0,2 mm e fixado em álcool 70%. As larvas de Chironomidae foram identificadas até a categoria de gênero. Foram encontradas 1478 larvas de Chironomidae pertencentes a 19 gêneros. Polypedilum, Tanytarsus e Chironomus foram registrados em todos os ambientes. As maiores densidades e diversidade de Chironomidae foram registradas nos períodos de águas baixas, especialmente em ambientes lênticos. A variação da densidade, dominância e diversidade de Chironomidae entre as duas coletas foi influenciada, principalmente, pelo ciclo hidrológico e pelo oxigênio dissolvido, enquanto que a variação espacial esteve associada ao tipo de sedimento, porcentagem de matéria orgânica e a presença ou ausência de macrófitas aquáticas.The present study had the aim to identify possible differences in the community structure of Chironomidae larvae in four different environments of the upper Paraná river floodplain with different characteristics and to analyze the influence of abiotic factors and variations in the hydrometric level of the community. Samplings were carried out in March and September, 2003. Four samplings were taken from each of the 12 collecting points: three for biological analysis and one for sediment analysis. Biological contents were washed with the aid of a system with 2.0; 1.0 and 0.2 mm sieves. Chironomidae larvae were

  12. Cutaneous Larva Migrans - a Typical Case Report

    OpenAIRE

    Santos, G.; João, A

    2013-01-01

    A larva migrans cutânea é frequente em regiões tropicais e sub-tropicais e é causada pela migração de larvas de nemátodos na pele. O diagnóstico é efectuado essencialmente pelas características epidemiológicas da dermatose e pela sua semiologia clínica. Geralmente o tratamento é bem sucedido com albendazol ou ivermectina. Descreve-se o caso clínico de uma mulher de 54 anos que regressou de férias na Jamaica há cerca de 15 dias. A doente iniciou no local, uma pápula eritematosa, bem deli...

  13. The Biology of Decapod Crustacean Larvae

    OpenAIRE

    Anger, Klaus

    2001-01-01

    About 90% of the extant species of the Decapoda live in oceans and adjacent coastal and estuarine regions, and most of them pass through a complex life history comprising a benthic (juvenile-adult) and a planktonic (larval) phase. The larvae show a wide array of adaptations to the pelagic environment, including modifications in functio-nal morphology, anatomy, the molting cycle, nutrition, growth, chemical composi-tion, meta-bo-lism, energy partitioning, ecology, and behavior. Due to these ad...

  14. The early stress responses in fish larvae.

    Science.gov (United States)

    Pederzoli, Aurora; Mola, Lucrezia

    2016-05-01

    During the life cycle of fish the larval stages are the most interesting and variable. Teleost larvae undergo a daily increase in adaptability and many organs differentiate and become active. These processes are concerted and require an early neuro-immune-endocrine integration. In larvae communication among the nervous, endocrine and immune systems utilizes several known signal molecule families which could be different from those of the adult fish. The immune-neuroendocrine system was studied in several fish species, among which in particular the sea bass (Dicentrarchus labrax), that is a species of great commercial interest, very important in aquaculture and thus highly studied. Indeed the immune system of this species is the best known among marine teleosts. In this review the data on main signal molecules of stress carried out on larvae of fish are considered and discussed. For sea bass active roles in the early immunological responses of some well-known molecules involved in the stress, such as ACTH, nitric oxide, CRF, HSP-70 and cortisol have been proposed. These molecules and/or their receptors are biologically active mainly in the gut before complete differentiation of gut-associated lymphoid tissue (GALT), probably acting in an autocrine/paracrine way. An intriguing idea emerges from all results of these researches; the molecules involved in stress responses, expressed in the adult cells of the hypothalamic-pituitary axis, during the larval life of fish are present in several other localizations, where they perform probably the same role. It may be hypothesized that the functions performed by hypothalamic-pituitary system are particularly important for the survival of the larva and therefore they comprises several other localizations of body. Indeed the larval stages of fish are very crucial phases that include many physiological changes and several possible stress both internal and environmental. PMID:26968620

  15. Microbiology and immunology of fish larvae

    OpenAIRE

    Vadstein, Olav; Bergh, Øivind; Gatesoupe, François-Joel; Galindo-Villegas, Jorge; Mulero, Victoriano; Picchietti, Simona; Scapigliati, Giuseppe; Makridis, Pavlos; Olsen, Yngvar; Dierckens, Kristof; Defoirdt, Tom; Boon, Nico; De Schryver, Peter; Bossier, Peter

    2013-01-01

    For most marine aquaculture species, one of the main bottlenecks is the stable production of high quality juveniles. The high and unpredictable mortality in the first weeks after hatching of marine fish larvae remains a challenging problem that needs to be solved. The severity of the problem differs between species, but cannot be considered adequately solved for any species. Both scientific evidence and experience in hatcheries for a variety of fish, shrimp and shellfish species are accumulat...

  16. Caffeine Taste Signaling in Drosophila Larvae.

    Science.gov (United States)

    Apostolopoulou, Anthi A; Köhn, Saskia; Stehle, Bernhard; Lutz, Michael; Wüst, Alexander; Mazija, Lorena; Rist, Anna; Galizia, C Giovanni; Lüdke, Alja; Thum, Andreas S

    2016-01-01

    The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal, and ventral organ). However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative co-receptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s). This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviors. PMID:27555807

  17. Requirements for in vitro germination of Paenibacillus larvae spores.

    Science.gov (United States)

    Alvarado, Israel; Phui, Andy; Elekonich, Michelle M; Abel-Santos, Ernesto

    2013-03-01

    Paenibacillus larvae is the causative agent of American foulbrood (AFB), a disease affecting honey bee larvae. First- and second-instar larvae become infected when they ingest food contaminated with P. larvae spores. The spores then germinate into vegetative cells that proliferate in the midgut of the honey bee. Although AFB affects honey bees only in the larval stage, P. larvae spores can be distributed throughout the hive. Because spore germination is critical for AFB establishment, we analyzed the requirements for P. larvae spore germination in vitro. We found that P. larvae spores germinated only in response to l-tyrosine plus uric acid under physiologic pH and temperature conditions. This suggests that the simultaneous presence of these signals is necessary for spore germination in vivo. Furthermore, the germination profiles of environmentally derived spores were identical to those of spores from a biochemically typed strain. Because l-tyrosine and uric acid are the only required germinants in vitro, we screened amino acid and purine analogs for their ability to act as antagonists of P. larvae spore germination. Indole and phenol, the side chains of tyrosine and tryptophan, strongly inhibited P. larvae spore germination. Methylation of the N-1 (but not the C-3) position of indole eliminated its ability to inhibit germination. Identification of the activators and inhibitors of P. larvae spore germination provides a basis for developing new tools to control AFB. PMID:23264573

  18. The Identification of Congeners and Aliens by Drosophila Larvae.

    Directory of Open Access Journals (Sweden)

    Francisco Del Pino

    Full Text Available We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b, Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles.

  19. The Identification of Congeners and Aliens by Drosophila Larvae

    Science.gov (United States)

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles. PMID:26313007

  20. Advection around ventilated U-shaped burrows: A model study

    Science.gov (United States)

    Brand, Andreas; Lewandowski, JöRg; Hamann, Enrico; Nützmann, Gunnar

    2013-05-01

    Advective transport in the porous matrix of sediments surrounding burrows formed by fauna such as Chironomus plumosus has been generally neglected. A positron emission tomography study recently revealed that the pumping activity of the midge larvae can indeed induce fluid flow in the sediment. We present a numerical model study which explores the conditions at which advective transport in the sediment becomes relevant. A 0.15 m deep U-shaped burrow with a diameter of 0.002 m within the sediment was represented in a 3-D domain. Fluid flow in the burrow was calculated using the Navier-Stokes equation for incompressible laminar flow in the burrow, and flow in the sediment was described by Darcy's law. Nonreactive and reactive transport scenarios were simulated considering diffusion and advection. The pumping activity of the model larva results in considerable advective flow in the sediment at reasonable high permeabilities with flow velocities of up to 7.0 × 10-6 m s-1 close to the larva for a permeability of 3 × 10-12 m2. At permeabilities below 7 × 10-13 m2 advection is negligible compared to diffusion. Reactive transport simulations using first-order kinetics for oxygen revealed that advective flux into the sediment downstream of the pumping larva enhances sedimentary uptake, while the advective flux into the burrow upstream of the larvae inhibits diffusive sedimentary uptake. Despite the fact that both effects cancel each other with respect to total solute uptake, the advection-induced asymmetry in concentration distribution can lead to a heterogeneous solute and redox distribution in the sediment relevant to complex reaction networks.

  1. Transcriptional response of honey bee larvae infected with the bacterial pathogen Paenibacillus larvae.

    Science.gov (United States)

    Cornman, Robert Scott; Lopez, Dawn; Evans, Jay D

    2013-01-01

    American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and a general immunity is achieved by larvae as they age, the basis of which has not been identified. To quickly identify a pool of candidate genes responsive to P. larvae infection, we sequenced transcripts from larvae inoculated with P. larvae at 12 hours post-emergence and incubated for 72 hours, and compared expression levels to a control cohort. We identified 75 genes with significantly higher expression and six genes with significantly lower expression. In addition to several antimicrobial peptides, two genes encoding peritrophic-matrix domains were also up-regulated. Extracellular matrix proteins, proteases/protease inhibitors, and members of the Osiris gene family were prevalent among differentially regulated genes. However, analysis of Drosophila homologs of differentially expressed genes revealed spatial and temporal patterns consistent with developmental asynchrony as a likely confounder of our results. We therefore used qPCR to measure the consistency of gene expression changes for a subset of differentially expressed genes. A replicate experiment sampled at both 48 and 72 hours post infection allowed further discrimination of genes likely to be involved in host response. The consistently responsive genes in our test set included a hymenopteran-specific protein tyrosine kinase, a hymenopteran specific serine endopeptidase, a cytochrome P450 (CYP9Q1), and a homolog of trynity, a zona pellucida domain protein. Of the known honey bee antimicrobial peptides, apidaecin was responsive at both time-points studied whereas hymenoptaecin was more consistent in its level of change between biological replicates and had the greatest increase in expression by RNA-seq analysis

  2. Comments on some species in Chironomini

    OpenAIRE

    Henk Vallenduuk

    2013-01-01

    Re-identification of some Chironomus species, Chironomus macani and C. dorsalis. Comments on information in Moller Pillot, 2009. A short discussion on the value of single reared larvae, cytology and DNA.

  3. Nutritional components affecting skeletal development in fish larvae

    OpenAIRE

    Cahu, Chantal; Zambonino, Jose-luis; Takeuchi, Toshio

    2003-01-01

    Marine fish larvae undergo major functional and morphological changes during the developmental stages and several factors can interfere with the normal development of larvae and affect fry quality. Skeletal malformations, such as spinal malformation-scoliosis, lordosis, coiled vertebral column-, missing or additional fin rays, bending opercle or jaw malformations, are frequently observed in hatchery-reared larvae. This paper reviews the effects of some nutritional components on skeletal devel...

  4. Diversity of parasitoid Lepidopterans larvae on Brassicaceae in West Sumatra

    OpenAIRE

    FENI YUSMARIKA; YAHERWANDI; RUSDI RUSLI; NOVRI NELLY

    2010-01-01

    Nelly N, Rusli R, Yaherwandi, Yusmarika F (2010) Diversity of parasitoid Lepidopterans larvae on Brassicaceae. Biodiversitas 11: 93-96. Diversity of parasitoid lepidopterans larvae on Brassicaceae was conducted in several Brassicaceae areas in West Sumatra. The objective of the research was to study the diversity of parasitoid lepidopterans larvae on Brassicaceae. Sampling was conducted on Brassicaceae plants: cabbage, cauliflower, petsai and sawi. It was taken five samples in every plot, by ...

  5. Identification of West African estuarine shrimp and crab larvae

    OpenAIRE

    Jonathan, G.E.; Powell, C. B.; A.I. Hart

    1985-01-01

    The paper deals with the decapod crustacean larvae likely to be found in fresh and brackish waters in tropical west Africa. It summarizes results from an ongoing program of describing larvae hatched directly from adults of known species, to provide the identification keys necessary for applied research on nursery grounds, plankton ecology and pollution effects. A preliminary key to stage - 1 larvae is given for approximately 40 species. In includes all the genera, and nearly all the species, ...

  6. Larva migrans cutanea: reporte de cuatro casos

    Directory of Open Access Journals (Sweden)

    Melvis Vivian Pérez Ruch

    2014-01-01

    Full Text Available Introducción: la larva migrans cutánea es una parasitosis que constituye una zoonosis frecuente en zonas tropicales, producida por la penetración y desplazamiento a través de la piel de larvas de nemátodos, como Ancylostoma brazilensis y Ancylostoma caninum. El cuadro clínico es característico y se diagnostica mediante la observación macroscópica de las lesiones serpiginosas debajo de la piel. Los antecedentes están dados por contacto con tierra o arena contaminadas como ocurre en niños que juegan en esos lugares. Objetivo: reportar los hallazgos de esta parasitosis en infantes pertenecientes a dos áreas de salud del municipio Camagüey, durante el período 2010 - 2013. Caso Clínico: en el laboratorio de Microbiología de la policlínica de especialidades pediátricas, se diagnosticaron cuatro niños con larva migrans cutánea de 1, 2, 7 y 11 años de edad, el primero con localización perineal, el segundo, en la espalda, el tercero en glúteos, miembros inferiores y superiores y el cuarto en región glútea y vulvar. En los cuatro casos las lesiones fueron características y se observó el trayecto ondulado del parásito a través de la piel. Los cuatros pacientes evolucionaron satisfactoriamente con tratamiento antiparásito. Conclusiones: dada la molestia, e irritabilidad que ocasiona esta parasitosis, así como la posible evolución tórpida de la misma es importante que en las áreas de 218 salud se tenga en cuenta para su oportuno diagnóstico y tratamiento satisfactorio en bien de los pacientes afectados.

  7. Modeling peripheral olfactory coding in Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Derek J Hoare

    Full Text Available The Drosophila larva possesses just 21 unique and identifiable pairs of olfactory sensory neurons (OSNs, enabling investigation of the contribution of individual OSN classes to the peripheral olfactory code. We combined electrophysiological and computational modeling to explore the nature of the peripheral olfactory code in situ. We recorded firing responses of 19/21 OSNs to a panel of 19 odors. This was achieved by creating larvae expressing just one functioning class of odorant receptor, and hence OSN. Odor response profiles of each OSN class were highly specific and unique. However many OSN-odor pairs yielded variable responses, some of which were statistically indistinguishable from background activity. We used these electrophysiological data, incorporating both responses and spontaneous firing activity, to develop a bayesian decoding model of olfactory processing. The model was able to accurately predict odor identity from raw OSN responses; prediction accuracy ranged from 12%-77% (mean for all odors 45.2% but was always significantly above chance (5.6%. However, there was no correlation between prediction accuracy for a given odor and the strength of responses of wild-type larvae to the same odor in a behavioral assay. We also used the model to predict the ability of the code to discriminate between pairs of odors. Some of these predictions were supported in a behavioral discrimination (masking assay but others were not. We conclude that our model of the peripheral code represents basic features of odor detection and discrimination, yielding insights into the information available to higher processing structures in the brain.

  8. Learning and Memory in Zebrafish Larvae

    Directory of Open Access Journals (Sweden)

    Adam Christopher Roberts

    2013-08-01

    Full Text Available Larval zebrafish possess several experimental advantages for investigating the molecular and neural bases of learning and memory. Despite this, neuroscientists have only recently begun to use these animals to study memory. However, in a relatively short period of time a number of forms of learning have been described in zebrafish larvae, and significant progress has been made toward their understanding. Here we provide a comprehensive review of this progress; we also describe several promising new experimental technologies currently being used in larval zebrafish that are likely to contribute major insights into the processes that underlie learning and memory.

  9. Fate of pharmaceuticals and pesticides in fly larvae composting.

    Science.gov (United States)

    Lalander, C; Senecal, J; Gros Calvo, M; Ahrens, L; Josefsson, S; Wiberg, K; Vinnerås, B

    2016-09-15

    A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (pesticides into the environment. PMID:27177134

  10. Biodiversity of Insect Larvae in Streams at Jobolarangan Forest

    OpenAIRE

    MANAN EFENDI; EDWI MAHAJOENO; ARDIANSYAH

    2001-01-01

    Insect larvae are macro-invertebrate that becomes the most perfect indicator of aquatic-environmental health. Natural streams usually determined by its insect-larvae community in a good condition, in which their taxonomic diversity and richness are high. The objective of the research was to know the taxonomic diversity and richness of insect-larvae family in streams at Jobolarangan forest. The larvae were sampled using net-surber (dip-net) in three location of streams, i.e.: Parkiran (1773 m ...

  11. Biofilms and Marine Invertebrate Larvae: What Bacteria Produce That Larvae Use to Choose Settlement Sites

    Science.gov (United States)

    Hadfield, Michael G.

    2011-01-01

    Communities of microorganisms form thin coats across solid surfaces in the sea. Larvae of many marine invertebrates use biofilm components as cues to appropriate settlement sites. Research on the tube-dwelling polychaete worm Hydroides elegans, a globally common member of biofouling communities, is described to exemplify approaches to understanding biofilm bacteria as a source of settlement cues and larvae as bearers of receptors for bacterial cues. The association of species of the bacterial genus Pseudoalteromonas with larval settlement in many phyla is described, and the question of whether cues are soluble or surface-bound is reviewed, concluding that most evidence points to surface-bound cues. Seemingly contradictory data for stimulation of barnacle settlement are discussed; possibly both explanations are true. Paleontological evidence reveals a relationship between metazoans and biofilms very early in metazoan evolution, and thus the receptors for bacterial cues of invertebrate larvae are very old and possibly unique. Finally, despite more than 60 years of intense investigation, we still know very little about either the bacterial ligands that stimulate larval settlement or the cellular basis of their detection by larvae.

  12. BACTERIAL FLORA OF RAINBOW TROUT LARVAE AND FRY (ONCORHYNCHUS MYKISS

    Directory of Open Access Journals (Sweden)

    Damir Kapetanović

    2003-09-01

    Full Text Available There are no information in available literature about the structure of bacterial flora in rainbow trout larvae and fry in the first days of their lives. The objective of our work has been to follow bacteroflora between the third and the eighth week of their lives. During 35 days of experiment bacteroflora of rainbow trout has been examined, along with following physico–chemical characteristics of water quality as well as it’s influence on health. Samples for bacteriological examination were taken from gill, heart and kidney areas and innoculated on the plates. Bacterial colonies were examined macroscopically, slides with Gram staining, and afterwords biochemical tests were performed. For identification, APILAB Plus programme (bio Mérieux, France was used. Bacterial population of rainbow trout larvae and fry changed in dependence with their age. Physico–chemical characteristics of water ranged within optimal values. Most of bacterial colonies originated from gill isolates (64,4 %, than from heart (21,8 % and kidney areas (13,8 %. The bacterial flora of larvae in incubator was composed mostly of Gram–positive bacteria (75,1 %, genera: Renibacterium (25 %, Lactobacillus (16,7 %, Staphilococcus (16,7 % and Corynebacterium (16,7 %. The transfer of larvae from incubator into the pools resulted in reducing bacterial flora (–66,7 % after 45 minute stay in the pool. Gram–negative bacteria, which have been represented in larvae in incubator with low percent (24, 9 %, after the transfer of larvae to the pools became dominant and represented more than 95 % of rainbow trout larvae and fry bacterial flora. Flavobacterium, Acinetobacter and Yersinia were the predominant Gram–negative genera in larvae in incubator, whereas Aeromonas, Pseudomonas, Flavobacterium and Pasteurella were the main isolates from rainbow trout larvae and fry until the end of experiment. Bacterial flora of larvae in incubator mostly consists of Gram–positive bacteria

  13. Characterization of six small HSP genes from Chironomus riparius (Diptera, Chironomidae): Differential expression under conditions of normal growth and heat-induced stress.

    Science.gov (United States)

    Martín-Folgar, Raquel; de la Fuente, Mercedes; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2015-10-01

    Small heat shock proteins (sHSPs) comprise the most numerous, structurally diverse, and functionally uncharacterized family of heat shock proteins. Several Hsp genes (Hsp 90, 70, 40, and 27) from the insect Chironomus riparius are widely used in aquatic toxicology as biomarkers for environmental toxins. Here, we conducted a comparative study and characterized secondary structure of the six newly identified sHsp genes Hsp17, Hsp21, Hsp22, Hsp23, Hsp24, and Hsp34. A characteristic α-crystallin domain is predicted in all the new proteins. Phylogenetic analysis suggests a strong relation to other sHSPs from insects and interesting evidence regarding evolutionary origin and duplication events. Comparative analysis of transcription profiles for Hsp27, Hsp70, and the six newly identified genes revealed that Hsp17, Hsp21, and Hsp22 are constitutively expressed under normal conditions, while under two different heat shock conditions these genes are either not activated or are even repressed (Hsp22). In contrast, Hsp23, Hsp24, and Hsp34 are significantly activated along with Hsp27 and Hsp70 during heat stress. These results strongly suggest functional differentiation within the small HSP subfamily and provide new data to help understand the coping mechanisms induced by stressful environmental stimuli. PMID:26129721

  14. The effect of high and low dissolved oxygen on the toxicity of oil sands coke and its leachate to Chironomus tentans

    International Nuclear Information System (INIS)

    A study was conducted to assess the effect of low dissolved oxygen on the long-term leaching potential of the toxic constituents found in coke. Coke is one of the waste products produced during the oil sand upgrading process used at Syncrude Canada Ltd. and Suncor Energy Inc. Coke is contaminated by metals and organic compounds which can leach into the environment. In this study, coke from both companies was exposed to reconstituted water and high dissolved oxygen for a period of 30 days, during which time the overlying water containing the leachate and the coke pore-water was chemically analyzed. The benthic macroinvertebrate, Chironomus tentans, was exposed to the aged coke and the overlying leachate after the 30 day period. The study did not reveal any major difference in the survival or growth between the dissolved oxygen treatments or any of the leachate treatments. The macroinvertebrate in the aged Syncrude grew significantly while the Suncor coke strongly inhibited both survival and growth of the macroinvertebrate. The study demonstrates that coke has the potential to negatively affect benthic organisms if it is used uncovered in an aquatic reclamation effort

  15. Cytogenetic index and functional genome alterations in Chironomus piger Strenzke (Diptera, Chironomidae) in the assessment of sediment pollution: a case study of Bulgarian and UK rivers.

    Science.gov (United States)

    Michailova, P; Ilkova, J; Dean, A P; White, K N

    2015-01-01

    The genotoxicity of trace metals in the sediments from a number of polluted sites on UK and Bulgarian rivers to Chironomus piger was assessed by an examination of genome instability as demonstrated by structural and functional changes to the salivary glands chromosomes. Based on the metal assays, the sediments were characterized to range from 'extremely' to 'strongly contaminated'. The cytogenetic index calculated on the basis of somatic structural chromosome alterations in the polytene chromosomes indicates a high level of pollution (0.07-0.06 in Bulgarian and 0.10-0.13 in UK stations). Exposure of C. piger to contaminated sediments resulted in a high level of chromosome damage as indicated by a somatic index of between 1.96 and 4.0. The transcription mechanism of the Balbiani rings and nucleolar organizer was damaged as their activity was either partially or completely suppressed. We have demonstrated that the C. piger genome is a sensitive sublethal indicator of sediment contamination, and is a highly suitable candidate for ecotoxicological monitoring of running waters. PMID:25450937

  16. Spinosad and neem seed kernel extract as bio-controlling agents for malarial vector,Anopheles stephensi and non-biting midge,Chironomus circumdatus

    Institute of Scientific and Technical Information of China (English)

    Kumar AN; Murugan K; Madhiyazhagan P; Prabhu K

    2011-01-01

    Objective:Midge egg masses are reported to support non-pathogenic strains of the cholera pathogen,Vibrio cholera (V. cholera). Mosquito born diseases have been reported to cause millions of death worldwide. The present research reveals the toxicity effect of spinosad and neem seed kernel extract (NSKE)against different larval stages ofAnopheles stephensi (An. stephensi) andChironomus circumdatus (Ch. circumdatus).Methods: The neem seeds were collected from Marudamalai hills, Bharathiar University, Coimbatore, India. Neem seed kernels were powdered, extracted and diluted for different concentrations (2 ppm to10 ppm). Spinosad was purchased from Kalpatharu pesticide Limited, Coimbatore, Tamil Nadu, India and thoroughly mixed with distilled water to prepare various concentrations (0.01 to0.08 ppm) and used for bioassay.Results: The results depict that spinosad is more toxic in lower concentrations when compared toNSKE and mosquitoes are more susceptible than chironomids. Lethal concentrations were evaluated using the observed mortality. The lowest LC50 value obtained from spinosad againstAn. stephensi and Ch. circumdatus were0.002 05 ppm and0.008 91 ppm. This study investigated on effect of Spinosad andNSKE on the biology of mosquito. The immature stages of both species were susceptible to Spinosad andNSKE. Spinosad andNSKE in individual as well as combined treatment provided additional days in development for mosquitoes.Conclusions:The results conclude that Spinosad andNSKE are potential larvicides against An. stephensi andCh. circumdatus.

  17. Effects of cobalt-60 gamma radiation on gnathostoma spinigerum larvae

    International Nuclear Information System (INIS)

    Gnathostoma spinigerum infective larvae were found to be very resistant to gamma ray. The larvae were still viable, motile and capable to infect white mice with no observable abnormality in both internal and external structures and their sizes after exposure to 0-7.0 KGy of gamma ray. At doses of 0, 0.3, 0.6, 1.0, 1.5, 2.0, 3.0, 5.0 and 7.0 KGy, the infective rates were 72%, 78%, 64%, 54%, 28%, 42%, 26%, 14% and 5% respectively. The infective rates of the irradiated larvae exposed to 8 KGy and 10 KGy of irradiation in mice became zero. The reduction of motility and infectivity was first observed after exposure of larvae to 1.5 KGy of gamma ray. It was also found that motility and infectivity decreased in relationship to the higher doses of gamma ray. At 10.0 KGy of irradiation which was the highest dose used in this experiment could not devitalize the larvae but inhibit infectivity. Irradiation of the larvae mixed in food prepared from fishes at 8 KGy was proved to inhibit the infectivity. On the study, the dose of 8.0 KGy was suggested to be the minimum effective dose that inhibited the infectivity of the infective stage. To confirm the effective dose, the mixture of the infective larvae and Somfuk, a local food, was treated by 8 KGy and these irradiated larvae precisely lost their infectivity in mice

  18. Cadmium and zinc reversibly arrest development of Artemia larvae

    Energy Technology Data Exchange (ETDEWEB)

    Bagshaw, J.C.; Rafiee, P.; Matthews, C.O.; MacRae, T.H.

    1986-08-01

    Despite the widespread distribution of heavy metals such as cadmium and zinc in the environment and their well-known cytotoxicity and embryotoxicity in mammals, comparatively little is known about their effect on aquatic organisms, particularly invertebrates. Post-gastrula and early larval development of the brine shrimp, Artemia, present some useful advantages for studies of developmental aspects of environmental toxicology. Dormant encysted gastrulae, erroneously called brine shrimp eggs, can be obtained commercially and raised in the laboratory under completely defined conditions. Following a period of post-gastrula development within the cyst, pre-nauplius larvae emerge through a crack in the cyst shell. A few hours later, free-swimming nauplius larvae hatch. Cadmium is acutely toxic to both adults and nauplius larvae of Artemia, but the reported LC50s are as high as 10 mM, depending on larval age. In this paper the authors show that pre-nauplius larvae prior to hatching are much more sensitive to cadmium than are hatched nauplius larvae. At 0.1 ..mu..m, cadmium retards development and hatching of larvae; higher concentrations block hatching almost completely and thus are lethal. However, the larvae arrested at the emergence stage survive for 24 hours or more before succumbing to the effects of cadmium, and during this period the potentially lethal effect is reversible if the larvae are placed in cadmium-free medium. The effects of zinc parallel those of cadmium, although zinc is somewhat less toxic than cadmium at equal concentrations.

  19. Complete Genome Sequences of Five Paenibacillus larvae Bacteriophages.

    Science.gov (United States)

    Sheflo, Michael A; Gardner, Adam V; Merrill, Bryan D; Fisher, Joshua N B; Lunt, Bryce L; Breakwell, Donald P; Grose, Julianne H; Burnett, Sandra H

    2013-01-01

    Paenibacillus larvae is a pathogen of honeybees that causes American foulbrood (AFB). We isolated bacteriophages from soil containing bee debris collected near beehives in Utah. We announce five high-quality complete genome sequences, which represent the first completed genome sequences submitted to GenBank for any P. larvae bacteriophage. PMID:24233582

  20. Bacteria Present in Comadia redtenbacheri Larvae (Lepidoptera: Cossidae).

    Science.gov (United States)

    Hernández-Flores, L; Llanderal-Cázares, C; Guzmán-Franco, A W; Aranda-Ocampo, S

    2015-09-01

    The external and internal culturable bacterial community present in the larvae of Comadia redtenbacheri Hammerschmidt, an edible insect, was studied. Characterization of the isolates determined the existence of 18 morphotypes and phylogenetic analysis of the 16S rRNA gene revealed the existence of Paenibacillus sp., Bacillus safensis, Pseudomonas sp., Bacillus pseudomycoides, Corynebacterium variabile, Enterococcus sp., Gordonia sp., Acinetobacter calcoaceticus, Arthrobacter sp., Micrococcus sp., and Bacillus cereus. Greater diversity of bacteria was found in those larvae obtained from vendors than in those directly taken from Agave plants in nature. Many of the larvae obtained from vendors presented signs of potential disease, and after the analysis, results showed a greater bacterial community compared with the larvae with a healthy appearance. This indicates that bacterial flora can vary in accordance with how the larvae are handled during extraction, collection, and transport. PMID:26336239

  1. External Ophthalmomyiasis Caused by a Rare Infesting Larva, Sarcophaga argyrostoma

    Directory of Open Access Journals (Sweden)

    Shmuel Graffi

    2013-01-01

    Full Text Available Purpose. External ophthalmomyiasis (EO is caused by infesting larvae belonging to various species of flies. Most documented cases result from sheep (Oestrus ovis and Russian (Rhinoestrus purpureus botfly larvae, but we recently discovered a rare case of EO caused by flesh fly (Sarcophaga argyrostoma larvae. Here, we report the case of a patient with EO who had been hospitalized and sedated for 1 week because of unrelated pneumonia. Methods. Case report. Results. A total of 32 larvae were removed from the adnexae of both eyes. Larvae identification was confirmed through DNA analysis. Treatment with topical tobramycin resulted in complete resolution of EO. Conclusion. EO can be caused by S. argyrostoma, and the elderly and debilitated may require extra ocular protection against flies during sedation.

  2. Evaluation of Paracentrotus lividus (Lamarck, 1816) exotrophic larvae as live feed for marine decapod crustacean larvae

    OpenAIRE

    Repolho, Tiago Filipe Baptista da Rosa, 1974-

    2012-01-01

    Tese de doutoramento, Biologia (Biologia Marinha e Aquacultura), Universidade de Lisboa, Faculdade de Ciências, 2012 In the present study, we have evaluated 4‐arm exotrophic larvae of sea urchin Paracentrotus lividus (Echinodermata: Echinoidea) as live feed in marine decapod crustacean larviculture, in comparison to Artemia spp. naupliar stages, a commonly used live prey in marine hatcheries. We therefore investigated several key parameters to assess the potential of P. lividus plutei as l...

  3. How to kill the honey bee larva: genomic potential and virulence mechanisms of Paenibacillus larvae.

    Science.gov (United States)

    Djukic, Marvin; Brzuszkiewicz, Elzbieta; Fünfhaus, Anne; Voss, Jörn; Gollnow, Kathleen; Poppinga, Lena; Liesegang, Heiko; Garcia-Gonzalez, Eva; Genersch, Elke; Daniel, Rolf

    2014-01-01

    Paenibacillus larvae, a Gram positive bacterial pathogen, causes American Foulbrood (AFB), which is the most serious infectious disease of honey bees. In order to investigate the genomic potential of P. larvae, two strains belonging to two different genotypes were sequenced and used for comparative genome analysis. The complete genome sequence of P. larvae strain DSM 25430 (genotype ERIC II) consisted of 4,056,006 bp and harbored 3,928 predicted protein-encoding genes. The draft genome sequence of P. larvae strain DSM 25719 (genotype ERIC I) comprised 4,579,589 bp and contained 4,868 protein-encoding genes. Both strains harbored a 9.7 kb plasmid and encoded a large number of virulence-associated proteins such as toxins and collagenases. In addition, genes encoding large multimodular enzymes producing nonribosomally peptides or polyketides were identified. In the genome of strain DSM 25719 seven toxin associated loci were identified and analyzed. Five of them encoded putatively functional toxins. The genome of strain DSM 25430 harbored several toxin loci that showed similarity to corresponding loci in the genome of strain DSM 25719, but were non-functional due to point mutations or disruption by transposases. Although both strains cause AFB, significant differences between the genomes were observed including genome size, number and composition of transposases, insertion elements, predicted phage regions, and strain-specific island-like regions. Transposases, integrases and recombinases are important drivers for genome plasticity. A total of 390 and 273 mobile elements were found in strain DSM 25430 and strain DSM 25719, respectively. Comparative genomics of both strains revealed acquisition of virulence factors by horizontal gene transfer and provided insights into evolution and pathogenicity. PMID:24599066

  4. Comparative proteomic analysis of surface proteins of Trichinella spiralis muscle larvae and intestinal infective larvae.

    Science.gov (United States)

    Liu, Ruo Dan; Cui, Jing; Liu, Xiao Lin; Jiang, Peng; Sun, Ge Ge; Zhang, Xi; Long, Shao Rong; Wang, Li; Wang, Zhong Quan

    2015-10-01

    The critical step for Trichinella spiralis infection is that muscle larvae (ML) are activated to intestinal infective larvae (IIL) and invade intestinal epithelium to further develop. The IIL is its first invasive stage, surface proteins are directly exposed to host environment and are crucial for larval invasion and development. In this study, shotgun LC-MS/MS was used to analyze surface protein profiles of ML and IIL. Totally, 41 proteins common to both larvae, and 85 ML biased and 113 IIL biased proteins. Some proteins (e.g., putative scavenger receptor cysteine-rich domain protein and putative onchocystatin) were involved in host-parasite interactions. Gene ontology analysis revealed that proteins involved in generation of precursor metabolites and energy; and nucleobase, nucleoside, nucleotide and nucleic acid metabolic process were enriched in IIL at level 4. Some IIL biased proteins might play important role in larval invasion and development. qPCR results confirmed the high expression of some genes in IIL. Our study provides new insights into larval invasion, host-Trichinella interaction and for screening vaccine candidate antigens. PMID:26184560

  5. Larva migrans within scalp sebaceous gland Larva migrans em glândula sebácea do couro cabeludo

    Directory of Open Access Journals (Sweden)

    Lucinda Calheiros Guimarães

    1999-04-01

    Full Text Available A case of larva migrans or serpiginous linear dermatitis on the scalp of a teenager is reported. An ancylostomid larva was found within a sebaceous gland acinus. The unusual skin site for larva migrans as well as the penetration through the sebaceous gland are highlighted. The probable mechanism by which the parasite reached the skin adnexa is discussed.Relata-se caso de larva migrans ou dermatite linear serpiginosa no couro cabeludo de adolescente, no qual o ancilostomídeo foi encontrado no interior de glândula sebácea. Destaca-se a possibilidade do helminto sediar-se em locais pouco usuais, das glândulas sebáceas serem via de penetração de larvas na pele e discute-se o provável mecanismo pelo qual o agente implantou-se no anexo cutâneo.

  6. Pakomáři rodu .i.Chironomus./i. MEIGEN (Diptera, Chironomidae) v Novohradských horách (jižní Čechy)

    Czech Academy of Sciences Publication Activity Database

    Matěna, Josef; Matěnová, V.

    České Budějovice : Jihočeská univerzita a Entomologický ústav AV ČR, 2002 - (Papáček, M.), s. 241-244 ISBN 80-7040-524-4. [Biodiverzita a přírodní podmínky Novohradských hor.. Nové Hrady (CZ), 10.01.2002-11.01.2002] R&D Projects: GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6017912 Keywords : chironomus * macrozoobenthos * ecology Subject RIV: EH - Ecology, Behaviour

  7. Biodiversity of Insect Larvae in Streams at Jobolarangan Forest

    Directory of Open Access Journals (Sweden)

    MANAN EFENDI

    2001-07-01

    Full Text Available Insect larvae are macro-invertebrate that becomes the most perfect indicator of aquatic-environmental health. Natural streams usually determined by its insect-larvae community in a good condition, in which their taxonomic diversity and richness are high. The objective of the research was to know the taxonomic diversity and richness of insect-larvae family in streams at Jobolarangan forest. The larvae were sampled using net-surber (dip-net in three location of streams, i.e.: Parkiran (1773 m asl., Mrutu (1875 m asl., and Air Terjun (1600 m asl.. The screened insect-larvae were grouped its family and counted their individual number. The diversity was counted using Shanon-Weiner diversity indices. In this research was found 12 families of insect-larvae consisted of two families of Odonata order, 3 families of Coleopteran order, and a family of Lepidoptera. Nine families identified, while the three insect-larvae i.e. 2 of Coleoptera and 1 of Lepidoptera were not identified yet. The Parkiran station indicated the highest diversity index of 0.1436.

  8. A multi-platform metabolomics approach demonstrates changes in energy metabolism and the transsulfuration pathway in Chironomus tepperi following exposure to zinc

    Energy Technology Data Exchange (ETDEWEB)

    Long, Sara M., E-mail: hoskins@unimelb.edu.au [Centre for Aquatic Pollution, Identification and Management (CAPIM), School of BioSciences, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, 3052 (Australia); Tull, Dedreia L., E-mail: dedreia@unimelb.edu.au [Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, Parkville, 3052 (Australia); Jeppe, Katherine J., E-mail: k.jeppe@unimelb.edu.au [Centre for Aquatic Pollution, Identification and Management (CAPIM), School of BioSciences, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, 3052 (Australia); Centre for Aquatic Pollution, Identification and Management (CAPIM), School of BioSciences, The University of Melbourne, 3010 (Australia); De Souza, David P., E-mail: desouzad@unimelb.edu.au [Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, Parkville, 3052 (Australia); Dayalan, Saravanan, E-mail: sdayalan@unimelb.edu.au [Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, Parkville, 3052 (Australia); Pettigrove, Vincent J., E-mail: vpet@unimelb.edu.au [Centre for Aquatic Pollution, Identification and Management (CAPIM), School of BioSciences, The University of Melbourne, 3010 (Australia); McConville, Malcolm J., E-mail: malcolmm@unimelb.edu.au [Metabolomics Australia, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, Parkville, 3052 (Australia); Hoffmann, Ary A., E-mail: ary@unimelb.edu.au [Centre for Aquatic Pollution, Identification and Management (CAPIM), School of BioSciences, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, 3052 (Australia); School of BioSciences, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30 Flemington Road, Parkville, 3052 (Australia)

    2015-05-15

    Highlights: • An integrated metabolomics approach was applied to examine zinc exposure in midges. • Changes in carbohydrate and energy metabolism were observed using GC–MS. • Transsulfuration pathway is affected by zinc exposure. • Heavy metals other than zinc affect the transsulfuration pathways differently. - Abstract: Measuring biological responses in resident biota is a commonly used approach to monitoring polluted habitats. The challenge is to choose sensitive and, ideally, stressor-specific endpoints that reflect the responses of the ecosystem. Metabolomics is a potentially useful approach for identifying sensitive and consistent responses since it provides a holistic view to understanding the effects of exposure to chemicals upon the physiological functioning of organisms. In this study, we exposed the aquatic non-biting midge, Chironomus tepperi, to two concentrations of zinc chloride and measured global changes in polar metabolite levels using an untargeted gas chromatography–mass spectrometry (GC–MS) analysis and a targeted liquid chromatography–mass spectrometry (LC–MS) analysis of amine-containing metabolites. These data were correlated with changes in the expression of a number of target genes. Zinc exposure resulted in a reduction in levels of intermediates in carbohydrate metabolism (i.e., glucose 6-phosphate, fructose 6-phosphate and disaccharides) and an increase in a number of TCA cycle intermediates. Zinc exposure also resulted in decreases in concentrations of the amine containing metabolites, lanthionine, methionine and cystathionine, and an increase in metallothionein gene expression. Methionine and cystathionine are intermediates in the transsulfuration pathway which is involved in the conversion of methionine to cysteine. These responses provide an understanding of the pathways affected by zinc toxicity, and how these effects are different to other heavy metals such as cadmium and copper. The use of complementary

  9. Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival.

    Science.gov (United States)

    Maul, Jonathan D; Brennan, Amanda A; Harwood, Amanda D; Lydy, Michael J

    2008-12-01

    Pyrethroids and fipronil insecticides partition to sediment and organic matter in aquatic systems and may pose a risk to organisms that use these matrices. It has been suggested that bioavailability of sediment-sorbed pesticides is reduced, but data on toxicity of sediment-associated pesticides for pyrethroids and fipronil are limited. In the current study, 10-d sediment exposures were conducted with larval Chironomus tentans for bifenthrin, lambda-cyhalothrin, permethrin, fipronil, fipronil-sulfide, and fipronil-sulfone, the last two being common fipronil metabolites. Sublethal endpoints included immobilization, instantaneous growth rate (IGR), body condition index, and growth estimated by ash-free dry mass (AFDM). Pyrethroid lethal concentrations to 50% of the population (LC50s) were 6.2, 2.8, and 24.5 microg/g of organic carbon (OC) for bifenthrin, lambda-cyhalothrin, and permethrin, respectively; with the former two lower than previously published estimates. Fipronil, fipronil-sulfide, and fipronil-sulfone LC50 values were 0.13, 0.16, and 0.12 microg/g of OC, respectively. Ratios of LC50s to sublethal endpoints (immobilization, IGR, and AFDM) ranged from 0.90 to 9.03. The effects on growth observed in the present study are important because of the unique dipteran life cycle involving pupation and emergence events. Growth inhibition would likely lead to ecological impacts similar to mortality (no emergence and thus not reproductively viable) but at concentrations up to 4.3 times lower than the LC50 for some compounds. In addition, C. tentans was highly sensitive to fipronil and metabolites, suggesting that dipterans may be important for estimating risk and understanding effects of phenylpyrazole-class insecticides on benthic macroinvertebrate communities. PMID:18699702

  10. A multi-platform metabolomics approach demonstrates changes in energy metabolism and the transsulfuration pathway in Chironomus tepperi following exposure to zinc

    International Nuclear Information System (INIS)

    Highlights: • An integrated metabolomics approach was applied to examine zinc exposure in midges. • Changes in carbohydrate and energy metabolism were observed using GC–MS. • Transsulfuration pathway is affected by zinc exposure. • Heavy metals other than zinc affect the transsulfuration pathways differently. - Abstract: Measuring biological responses in resident biota is a commonly used approach to monitoring polluted habitats. The challenge is to choose sensitive and, ideally, stressor-specific endpoints that reflect the responses of the ecosystem. Metabolomics is a potentially useful approach for identifying sensitive and consistent responses since it provides a holistic view to understanding the effects of exposure to chemicals upon the physiological functioning of organisms. In this study, we exposed the aquatic non-biting midge, Chironomus tepperi, to two concentrations of zinc chloride and measured global changes in polar metabolite levels using an untargeted gas chromatography–mass spectrometry (GC–MS) analysis and a targeted liquid chromatography–mass spectrometry (LC–MS) analysis of amine-containing metabolites. These data were correlated with changes in the expression of a number of target genes. Zinc exposure resulted in a reduction in levels of intermediates in carbohydrate metabolism (i.e., glucose 6-phosphate, fructose 6-phosphate and disaccharides) and an increase in a number of TCA cycle intermediates. Zinc exposure also resulted in decreases in concentrations of the amine containing metabolites, lanthionine, methionine and cystathionine, and an increase in metallothionein gene expression. Methionine and cystathionine are intermediates in the transsulfuration pathway which is involved in the conversion of methionine to cysteine. These responses provide an understanding of the pathways affected by zinc toxicity, and how these effects are different to other heavy metals such as cadmium and copper. The use of complementary

  11. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    International Nuclear Information System (INIS)

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented

  12. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Science.gov (United States)

    Aladawi, M. A.; Albarodi, H.; Hammoudeh, A.; Shamma, M.; Sharabi, N.

    2006-01-01

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  13. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Aladawi, M.A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)]. E-mail: Scientific@aec.org.sy; Albarodi, H. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Hammoudeh, A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Shamma, M. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Sharabi, N. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2006-01-15

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  14. Anguilliform larvae collected off North Carolina

    Science.gov (United States)

    Ross, S.W.; Casazza, T.L.; Quattrini, A.M.; Sulak, K.J.

    2007-01-01

    The distinctive larval stage of eels (leptocephalus) facilitates dispersal through prolonged life in the open ocean. Leptocephali are abundant and diverse off North Carolina, yet data on distributions and biology are lacking. The water column (from surface to 1,293 m) was sampled in or near the Gulf Stream off Cape Hatteras, Cape Lookout, and Cape Fear, North Carolina during summer through fall of 1999-2005, and leptocephali were collected by neuston net, plankton net, Tucker trawl, and dip net. Additional samples were collected nearly monthly from a transect across southern Onslow Bay, North Carolina (from surface to 91 m) from April 2000 to December 2001 by bongo and neuston nets, Methot frame trawl, and Tucker trawl. Overall, 584 tows were completed, and 224 of these yielded larval eels. The 1,295 eel leptocephali collected (combining all methods and areas) represented at least 63 species (nine families). Thirteen species were not known previously from the area. Dominant families for all areas were Congridae (44% of individuals, 11 species), Ophichthidae (30% of individuals, 27 species), and Muraenidae (22% of individuals, ten species). Nine taxa accounted for 70% of the overall leptocephalus catches (in order of decreasing abundance): Paraconger caudilimbatus (Poey), Gymnothorax ocellatus Agassiz complex, Ariosoma balearicum (Delaroche), Ophichthus gomesii (Castelnau), Callechelys muraena Jordan and Evermann, Letharchus aliculatus McCosker, Rhynchoconger flavus (Goode and Bean), Ophichthus cruentifer (Goode and Bean), Rhynchoconger gracilior (Ginsburg). The top three species represented 52% of the total eel larvae collected. Most leptocephali were collected at night (79%) and at depths > 45 m. Eighty percent of the eels collected in discrete depth Tucker trawls at night ranged from mean depths of 59-353 m. A substantial number (38% of discrete depth sample total) of larval eels were also collected at the surface (neuston net) at night. Daytime leptocephalus

  15. The larvae of decapods and fishes of Amba estuary, Maharashtra

    Digital Repository Service at National Institute of Oceanography (India)

    Paulinose, V.T.; Devi, C.B.L.; Govindan, K.; Gajbhiye, S.N.; Nair, V.R.

    Larvae of fishes and decapods found in zooplankton collections from two stations (Mankule and Patalganga) in Amba estuary adjoining Mumbai harbour were studied during 1989-90 covering three seasons. The percentage contributions of decapods and fish...

  16. Microbial modulation of behavior and stress responses in zebrafish larvae.

    Science.gov (United States)

    Davis, Daniel J; Bryda, Elizabeth C; Gillespie, Catherine H; Ericsson, Aaron C

    2016-09-15

    The influence of the microbiota on behavior and stress responses is poorly understood. Zebrafish larvae have unique characteristics that are advantageous for neuroimmune research, however, they are currently underutilized for such studies. Here, we used germ-free zebrafish to determine the effects of the microbiota on behavior and stress testing. The absence of a microbiota dramatically altered locomotor and anxiety-related behavior. Additionally, characteristic responses to an acute stressor were also obliterated in larvae lacking exposure to microbes. Lastly, treatment with the probiotic Lactobacillus plantarum was sufficient to attenuate anxiety-related behavior in conventionally-raised zebrafish larvae. These results underscore the importance of the microbiota in communicating to the CNS via the microbiome-gut-brain axis and set a foundation for using zebrafish larvae for neuroimmune research. PMID:27217102

  17. Microbial interference with hatch and survival of European eel larvae

    DEFF Research Database (Denmark)

    Sørensen, Sune Riis; Lauesen; Tomkiewicz, Jonna; de Schryver, P.

    Recent research has significantly improved our knowledge and capabilities in the field of in vitro production of yolk sac larvae from European eel (Anguilla anguilla). Female broodstock European eels are matured by weekly administration of pituitary extract and male eels with hCG (human chorionic...... gonadotropin), which afford gametes for in vitro fertilization studies. The maturing process may lead to mass hatchings of up to ½ million larvae of which some survive the entire yolk sac phase. However, the rearing of larvae suffers from high larval mortalities, and water quality might be a crucial factor for...... larval survival in rearing systems. By applying antibiotic treatment as a research tool, it was possible to determine the extent of microbial interference in the production of high numbers of good quality larvae. By controlling microbiota during egg and larval incubation, the egg hatching success and...

  18. Characterization of secreted proteases of Paenibacillus larvae, potential virulence factors in honeybee larval infection

    Science.gov (United States)

    Paenibacillus larvae is the causative agent of American Foulbrood (AFB), the most severe bacterial disease that affects honeybee larvae. AFB causes a significant decrease in the honeybee population affecting the beekeeping industry and agricultural production. After infection of larvae, P. larvae se...

  19. Maya Index and Larva Density Aedes Aegypti Toward Dengue Infection

    OpenAIRE

    Sang G. Purnama; Tri Baskoro

    2012-01-01

    South Denpasar District was of there as with the highest dengue cases in Bali province. The number of mosquito breeding places and larvae density become risk factor that influenced the spreading of mosquitoes. Maya index was an indicator to measure the amount of waterreservoirs can be breeding places for mosquitoes. Knowing the relationship between maya index and density of larvae and pupae of Ae.aegypti toward dengue infection in South Denpasar District. The study was observational analytic ...

  20. Decapod larvae dynamics on Berlengas Biosphere Reserve (UNESCO) - Portugal

    OpenAIRE

    Lénia Da Fonseca Alexandre Rato; Henrique Queiroga

    2014-01-01

    Berlengas Biosphere Reserve of UNESCO (BBR) is located on the west coast of Portugal and is an important hotspot of biodiversity that needs to be described and monitored. Despite that, few or none studies had focus on decapod larvae populations. The present study intends to evaluate spatial and temporal dynamics of decapod larvae and its relation with oceanographic features. Sampling campaigns were performed between June 2010 and August 2012. Zooplankton samples were collected on a Bongo...

  1. Symbiotic bacteria enable olive fly larvae to overcome host defences

    OpenAIRE

    Ben-Yosef, Michael; Pasternak, Zohar; Jurkevitch, Edouard; Yuval, Boaz

    2015-01-01

    Ripe fruit offer readily available nutrients for many animals, including fruit fly larvae (Diptera: Tephritidae) and their associated rot-inducing bacteria. Yet, during most of their ontogeny, fruit remain chemically defended and effectively suppress herbivores and pathogens by high levels of secondary metabolites. Olive flies (Bactrocera oleae) are uniquely able to develop in unripe olives. Unlike other frugivorous tephritids, the larvae maintain bacteria confined within their midgut caeca. ...

  2. Microbial interference with hatch and survival of European eel larvae

    OpenAIRE

    Sørensen, Sune Riis; Lauesen,; Tomkiewicz, Jonna; De Schryver, P.

    2013-01-01

    Recent research has significantly improved our knowledge and capabilities in the field of in vitro production of yolk sac larvae from European eel (Anguilla anguilla). Female broodstock European eels are matured by weekly administration of pituitary extract and male eels with hCG (human chorionic gonadotropin), which afford gametes for in vitro fertilization studies. The maturing process may lead to mass hatchings of up to ½ million larvae of which some survive the entire yolk sac phase. Howe...

  3. Recording Field Potentials From Zebrafish Larvae During Escape Responses

    OpenAIRE

    Monesson-Olson, Bryan D.; Troconis, Eileen L.; Trapani, Josef G.

    2014-01-01

    Among vertebrates, startle responses are a ubiquitous method for alerting, and avoiding or escaping from alarming or dangerous stimuli. In zebrafish larvae, fast escape behavior is easily evoked through either acoustic or tactile stimuli. For example, a light touch to the head will excite trigeminal neurons that in turn excite a large reticulospinal neuron in the hindbrain called the Mauthner cell (M-cell). The M-cell action potential then travels down the contralateral trunk of the larva exc...

  4. The use of fly larvae for organic waste treatment.

    Science.gov (United States)

    Čičková, Helena; Newton, G Larry; Lacy, R Curt; Kozánek, Milan

    2015-01-01

    The idea of using fly larvae for processing of organic waste was proposed almost 100 years ago. Since then, numerous laboratory studies have shown that several fly species are well suited for biodegradation of organic waste, with the house fly (Musca domestica L.) and the black soldier fly (Hermetia illucens L.) being the most extensively studied insects for this purpose. House fly larvae develop well in manure of animals fed a mixed diet, while black soldier fly larvae accept a greater variety of decaying organic matter. Blow fly and flesh fly maggots are better suited for biodegradation of meat processing waste. The larvae of these insects have been successfully used to reduce mass of animal manure, fecal sludge, municipal waste, food scrapes, restaurant and market waste, as well as plant residues left after oil extraction. Higher yields of larvae are produced on nutrient-rich wastes (meat processing waste, food waste) than on manure or plant residues. Larvae may be used as animal feed or for production of secondary products (biodiesel, biologically active substances). Waste residue becomes valuable fertilizer. During biodegradation the temperature of the substrate rises, pH changes from neutral to alkaline, ammonia release increases, and moisture decreases. Microbial load of some pathogens can be substantially reduced. Both larvae and digested residue may require further treatment to eliminate pathogens. Facilities utilizing natural fly populations, as well as pilot and full-scale plants with laboratory-reared fly populations have been shown to be effective and economically feasible. The major obstacles associated with the production of fly larvae from organic waste on an industrial scale seem to be technological aspects of scaling-up the production capacity, insufficient knowledge of fly biology necessary to produce large amounts of eggs, and current legislation. Technological innovations could greatly improve performance of the biodegradation facilities and

  5. Phylogenetics links monster larva to deep-sea shrimp

    OpenAIRE

    Bracken-Grissom, Heather D; Felder, Darryl L.; Vollmer, Nicole L; Martin, Joel W.; Crandall, Keith A.

    2012-01-01

    Mid-water plankton collections commonly include bizarre and mysterious developmental stages that differ conspicuously from their adult counterparts in morphology and habitat. Unaware of the existence of planktonic larval stages, early zoologists often misidentified these unique morphologies as independent adult lineages. Many such mistakes have since been corrected by collecting larvae, raising them in the lab, and identifying the adult forms. However, challenges arise when the larva is remar...

  6. Antimicrobial activity of essential oils against Paenibacillus larvae

    OpenAIRE

    Gende, L. B.; Pires, Sância; Fernandez, N.J.; Damiani, M; Churio, M.S.; Fritz, R.; Eguaras, M. J.

    2012-01-01

    American foulbrood is a serious bacterial disease that affects Apis mellifera colonies; the causative agent is Paenibacillus larvae [1 ]. The aim of the study was to evaluate in vitro the antimicrobial activity of 32 essential oils against P. larvae. Oils from 21 botanical species were analyzed by gas chromatography (CG and CG/EM). All essential oils were classified according to the composition of their main components in two groups: benzene ring compounds (BRC) and terpene com...

  7. Using Real-time PCR for Identification of Paenibacillus larvae

    Directory of Open Access Journals (Sweden)

    Vladimíra Kňazovická

    2011-05-01

    Full Text Available The aim of the study was identification of Paenibacillus larvae that causes American foulbrood disease (AFB in colony of bees (Apis mellifera. Bacterial isolates originated from honey samples, because presence of P. larvae in honey is treated as early diagnostic of AFB. Intense proteolytic activity and no catalase activity are typical for Gram positive rod-shaped bacteria P. larvae. We diluted honey (1:2, heated at 80 °C for 10 min and inoculated on semiselective medium MYPGP agar with nalidixic acid. Plates were cultivated at 37 °C for 48 – 72 h under the aerobic conditions. Selected colonies were transferred on MYT agar and cultivated 24 h. We analysed 30 honey samples and found 27 bacterial isolates. All isolates were Gram positive and mainly rod-shaped. No catalase activity was documented for 6 from 27 isolates. Identification was finished by real-time PCR to detect the 16S rRNA gene of Paenibacillus larvae with real-time cycler Rotor-Gene 6000. As DNA template we used genomic DNA isolated with commercial kit and DNA lysate obtaining by boiled cells. We used 2 strains of P. larvae from CCM (Czech Collection of Microorganisms as positive control. The reliable method of detection P. larvae has important rule for beekeeping.

  8. Differential immunological responses induced by infection with female muscle larvae and newborn larvae of Trichinella pseudospiralis.

    Science.gov (United States)

    Wu, Z; Nagano, I; Asano, K; Liu, M Y; Takahashi, Y

    2013-05-20

    Trichinella pseudospiralis infection can modulate the immunological response of autoimmune and allergic diseases leading to the amelioration of these diseases. The present study was undertaken to compare immunity induced by adult worms and muscle larvae. Higher eosinophilia was observed from newborn larva (NBL) infection than from adult females while higher levels of IgE were observed in adult female infections over those induced by NBL. The IgG1 response to ES antigen was more prominent in infections with adult females. The IgG2 responses to larval crude antigen were prominent against NBL. The Th2 cytokine, IL-4 cytokine was elevated in adult female infection following re-stimulation with adult crude antigen and ES. Both infections induced strong IFN-γ responses. The present study demonstrates that adult female worms induced stronger Th2 responses (IgG1, IgE and IL-4 responses) than NBL. Further examination of the mechanisms involved in immune modulation may be helpful for identifying Trichinella-derived molecules responsible for regulating autoimmune and allergic diseases. PMID:23433605

  9. First record of larvae of Chironomidae (Insecta, Diptera) as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae), an ectosymbiont on larvae of Corydalidae (Megaloptera) Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae), um ectosimbionte de larvas de Corydalidae (Maegaloptera)

    OpenAIRE

    Susana Trivinho-Strixino; Fabio Laurindo da Silva; Francisco Valente-Neto

    2012-01-01

    First record of larvae of Chironomidae (Insecta, Diptera) as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae), an ectosymbiont on larvae of Corydalidae (Megaloptera). This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes) were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalop...

  10. First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera

    Directory of Open Access Journals (Sweden)

    Susana Trivinho-Strixino

    2012-09-01

    Full Text Available First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera. This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalopteran larvae had 24 Temnocephala sp. associated. Furthermore, eight of these Temnocephala worms had chironomid larvae in their gut contents, an interaction previously unknown. Gut content analyses revealed Corynoneura as the commonest chironomid, but larvae of Larsia, Rheotanytarsus and Tanytarsus were recorded as well. This study included Corydalus and Protochauliodes as hosts for Temnocephala, which might be important for this worm dispersion and population dynamics.

  11. The central nervous system of ascidian larvae.

    Science.gov (United States)

    Hudson, Clare

    2016-09-01

    Ascidians are marine invertebrate chordates. Their tadpole larvae contain a dorsal tubular nervous system, resulting from the rolling up of a neural plate. Along the anterior-posterior (A-P) axis, the central nervous system (CNS) is organized into a sensory vesicle, neck, trunk ganglion, and tail nerve cord and consists of approximately only 330 cells, of which around 100 are thought to be neurons. The organization of distinct neuronal cell types and neurotransmitter gene expression within the CNS has been described. The unique developmental mode of ascidians, with a small number of cells and a fixed cell division pattern, allows individual cells to be traced throughout development. This feature has led to the complete documentation of the cell lineages of certain cell types in the CNS. Thus, a step-by-step understanding of nervous system development from the initial stages of neural induction to the neurogenesis of individual neurons is a feasible goal. The genetic control of neural fate induction and early neural plate patterning are now well understood. The molecular mechanisms specifying the cholinergic neurons of the trunk ganglion as well as the pigment cells of the sensory organs are also well elucidated. In addition, studies have begun on the morphogenetic processes of neurulation. Remaining challenges include building an embryonic atlas integrating gene expression patterns, cell lineage, and neuronal cell types as well as developing the gene regulatory networks of cell fate specification and integrating them with the genetic control of morphogenesis. WIREs Dev Biol 2016, 5:538-561. doi: 10.1002/wdev.239 For further resources related to this article, please visit the WIREs website. PMID:27328318

  12. Amostragem por larva-única na vigilância de Aedes aegypti Single-larva sampling for Aedes aegypti surveillance

    Directory of Open Access Journals (Sweden)

    José Eduardo Bracco

    1995-04-01

    Full Text Available Com a finalidade de testar a metodologia de amostragem por larva-única na vigilância entomológica do Aedes aegypti, foram pesquisados domicílios do Município de Araraquara, SP (Brasil. Nos criadouros que continham larvas de Aedes uma delas foi coletada. Como controle, após a coleta da larva-única, todas as larvas foram coletadas para identificação posterior. Esse processo foi repetido no laboratório. Dos 447 domicílios visitados, apenas 12 foram considerados positivos e 20 criadouros foram identificados; destes, 13 continham larvas de Aedes; 5, larvas de Aedes e Culex e 2, larvas de Culex. Os resultados mostram o reconhecimento correto, no campo, de todos os criadouros, evidenciando que o método poderia ser utilizado na vigilância entomológica de municípios sem infestação domiciliar ou infestados apenas com uma única espécie de Aedes.Buildings in Araraquara city, Southeastern Brazil, were searched during a year for the presence of Aedes larvae using single larva sampling in order to check the single-larva methodology. In those breeding places in wich Aedes larvae were found, one of them was collected. As a control, after the single larva had been collected, all the larvae from the breeding place were collected for later identification. This process was repeated in the laboratory. Of the 447 domiciles searched, 12 were considered positive and 20 breeding places were found. Of the breeding places, 13 contained Aedes larvae, 5 both Aedes and Culex larvae and 2 Culex larvae only. The results show that all the breeding places in the field were properly recognited showing the method may be used for Aedes surveillance in cities infested with one species only or without any domiciliary infestation.

  13. Descrição da larva de Diastatops obscura (Fabricius (Odonata, Libellulidae Description of the larva of Diastatops obscura (Fabricius (Odonata, Libellulidae

    Directory of Open Access Journals (Sweden)

    N.D. Santos

    1993-01-01

    Full Text Available The larva of Diastatops obscura (Fabricius, 1775 is described and figured based on exuviae of last instar of reared specimes collected on still waters in São João river, Silva Jardim (22º38' - 42º18', Rio de Janeiro, Brazil. The relationship among the larva of D. obscura and larvae of Celithemis are discussed.

  14. Unexpected high losses of Anopheles gambiae larvae due to rainfall.

    Directory of Open Access Journals (Sweden)

    Krijn P Paaijmans

    Full Text Available BACKGROUND: Immature stages of the malaria mosquito Anopheles gambiae experience high mortality, but its cause is poorly understood. Here we study the impact of rainfall, one of the abiotic factors to which the immatures are frequently exposed, on their mortality. METHODOLOGY/PRINCIPAL FINDINGS: We show that rainfall significantly affected larval mosquitoes by flushing them out of their aquatic habitat and killing them. Outdoor experiments under natural conditions in Kenya revealed that the additional nightly loss of larvae caused by rainfall was on average 17.5% for the youngest (L1 larvae and 4.8% for the oldest (L4 larvae; an additional 10.5% (increase from 0.9 to 11.4% of the L1 larvae and 3.3% (from 0.1 to 3.4% of the L4 larvae were flushed away and larval mortality increased by 6.9% (from 4.6 to 11.5% and 1.5% (from 4.1 to 5.6% for L1 and L4 larvae, respectively, compared to nights without rain. On rainy nights, 1.3% and 0.7% of L1 and L4 larvae, respectively, were lost due to ejection from the breeding site. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that immature populations of malaria mosquitoes suffer high losses during rainfall events. As these populations are likely to experience several rain showers during their lifespan, rainfall will have a profound effect on the productivity of mosquito breeding sites and, as a result, on the transmission of malaria. These findings are discussed in the light of malaria risk and changing rainfall patterns in response to climate change.

  15. REARING CARP LARVAE (Cyprinus carpio IN CLOSED RECIRCULATORY SYSTEM (RAS

    Directory of Open Access Journals (Sweden)

    Anđelko Opačak

    2012-03-01

    Full Text Available Postembryonic rearing of carp larvae in closed recirculatory system was conducted in 2009 at the fish farm Ribnjak LLC, Donji Miholjac, Croatia. The research was conducted in two test groups (A and B with three iterations in each with a control group (C. Test group A (3 tanks x 250 l consisted of 150 000 larvae (density of 200 larvae•l-1, test group B (3 tanks x 500 l consisted of 600 000 larvae (density of 400 larvae•l-1, and the control group (C was a mud fish pond T-6 which was stocked by 800 000 larvae•ha-1 under standard production conditions. In this research, basic physical and chemical water parameters were controlled (temperature, oxygen, pH, total ammonia and nitrites. Initial measuring of carp larvae total length (TL was conducted prior to their placement into tanks (N=120. On the fourth, sixth, eighth and tenth day of research 20 larvae (N=140 were taken out of every tank as well as out of control group and measured. Feeding with live feed began on the third day after hatching (larval TL 6.00±0.36 mm. Ten minutes after feeding live feed to larvae for the first time, 20 larvae (N=120 were taken out of every tank and a high portion of larvae that accepted live feed (89.17±3.76% was determined by a magnifying glass. Feeding artificial feed began on the seventh day after the hatching. After ten minutes, a high portion of larvae who accepted artificial feed (96.67±2.58% was determined. Since the end of the research, the determined length increment (ITL per day was 0.41±0.04 mm, a very high survival rate was established (group A: 96%, group B: 93%. Feeding frequency was four times a day in five-hour intervals (at 06:00, 11:00,16:00 and 21:00 hours. The research was terminated after ten feeding days due to deteriorating condition of zoohygienic filter. The total of 3807 g of live feed and 1080 g of artificial feed was used.

  16. Feeding ecology of lake whitefish larvae in eastern Lake Ontario

    Science.gov (United States)

    Johnson, James H.; McKenna, James E.; Chalupnicki, Marc A.; Wallbridge, Tim; Chiavelli, Rich

    2009-01-01

    We examined the feeding ecology of larval lake whitefish (Coregonus clupeaformis) in Chaumont Bay, Lake Ontario, during April and May 2004-2006. Larvae were collected with towed ichthyoplankton nets offshore and with larval seines along the shoreline. Larval feeding periodicity was examined from collections made at 4-h intervals over one 24-h period in 2005. Inter-annual variation in diet composition (% dry weight) was low, as was spatial variation among collection sites within the bay. Copepods (81.4%), primarily cyclopoids (59.1%), were the primary prey of larvae over the 3-year period. Cladocerans (8.1%; mainly daphnids, 6.7%) and chironomids (7.3%) were the other major prey consumed. Larvae did not exhibit a preference for any specific prey taxa. Food consumption of lake whitefish larvae was significantly lower at night (i.e., 2400 and 0400 h). Substantial variation in diet composition occurred over the 24-h diel study. For the 24-h period, copepods were the major prey consumed (50.4%) and their contribution in the diet ranged from 29.3% (0400 h) to 85.9% (1200 h). Chironomids made up 33.4% of the diel diet, ranging from 8.0% (0800 h) to 69.9% (0400 h). Diel variation in the diet composition of lake whitefish larvae may require samples taken at several intervals over a 24-h period to gain adequate representation of their feeding ecology.

  17. Larvicidal activity of Brazilian plant essential oils against Coenagrionidae larvae.

    Science.gov (United States)

    Silva, D T; Silva, L L; Amaral, L P; Pinheiro, C G; Pires, M M; Schindler, B; Garlet, Q I; Benovit, S C; Baldisserotto, B; Longhi, S J; Kotzian, C B; Heinzmann, B M

    2014-08-01

    Odonate larvae can be serious pests that attack fish larvae, postlarvae, and fingerlings in fish culture tanks, causing significant loss in the supply and production of juveniles. This study reports a screen of the essential oils (EOs) of Nectandra megapotamica (Sprengel) Mez, Nectandra grandiflora Nees, Hesperozygis ringens (Bentham) Epling, Ocimum gratissimum L., Aloysia gratissima (Gillies & Hooker) Troncoso, and Lippia sidoides Chamisso against Coenagrionidae larvae. In addition, the most effective EO and its 50% lethal concentration (LC50) and chemical analysis are described. The larvae of Acanthagrion Selys, Homeoura Kennedy, Ischnura Charpentier, and Oxyagrion Selys were used to assess the EO effects. EO obtained from H. ringens, O. gratissimum, and L. sidoides showed the highest larvicidal effects at 19 h of treatment. The major constituents of the EO of H. ringens include pulegone and limonene, while eugenol and Z-beta-ocimene predominate in the EO of O. gratissimum, and carvacrol and rho-cymene were the major compounds of the EO of L. sidoides. Leaf EOs from H. ringens, O. gratissimum, and L. sidoides showed activity against Coenagrionidae larvae at similar concentrations with LC50s of 62.92, 75.05, and 51.65 microl liter(-1), respectively, and these were considered the most promising treatments. PMID:25195467

  18. Visceral larva migrans: migratory pattern of Toxocara canis in pigs

    DEFF Research Database (Denmark)

    Helwigh, Birgitte; Lind, Peter; Nansen, Peter

    1999-01-01

    The migratory pattern of Toxocara canis was investigated following infection of pigs with 60 000 infective eggs. Groups of six pigs were slaughtered at 7, 14 and 28 days after infection (p.i.), and the number of larvae in selected organs and muscles was determined by digestion. A group of uninfec...... in the pig. However, the importance of the pig as a paratenic host is probably minor, because of the relatively early death of most of the larvae....... uninfected pigs was used as negative controls for blood parameters and weight gain. Toxocara canis migrated well in the pig, although the relative numbers of larvae recovered decreased significantly during the experiment. On day 7 p.i., high numbers of larvae were recovered from the lymph nodes around the...... recovered from the brain on days 14 and 21, with a maximum on day 14 p.i. No larvae were found in the eyes. Severe pathological changes were observed in the liver and lungs, especially on day 14 p.i.; also, development of granulomas was observed in the kidneys. Finally, a strong specific antibody response...

  19. Larva migrans in India: veterinary and public health perspectives.

    Science.gov (United States)

    Sharma, Rajnish; Singh, B B; Gill, J P S

    2015-12-01

    Despite an important public health problem in developing world like India, larva migrans remains a neglected zoonosis. Cutaneous larva migrans, Visceral larva migrans, and Ocular larva migrans are the important clinical manifestations seen in humans in India. Although many nematode parasites have the ability to cause the infection, the disease primarily occurs due to Ancylostoma caninum and Toxocara canis. Presence of the infection in dogs is an indirect indication of its incidence in humans in endemic regions. In India, sporadic cases of this neglected but important parasitic zoonosis are the main implications of lack of diagnostic methods and under-reporting of human cases. Tropical climate in addition to overcrowding, poor hygiene and sanitation problems, stray dogs, open defecation by dogs and improper faecal disposal are the important factors for persistence of this disease in the country. Sanitary and hygienic measures, improved diagnostic techniques and surveillance programme in dogs as well as humans should be adopted for its effective control. Comprehensive collaborative efforts by physicians and veterinarians are required to tackle this problem in order to attain optimal health for humans, animals and the environment. Moreover, recognition of larva migrans as an important public health problem is the most important step to combat this neglected disease in developing countries like India. PMID:26688621

  20. Comparative analysis of Paenibacillus larvae genotypes isolated in Connecticut.

    Science.gov (United States)

    Dingman, Douglas W

    2015-08-01

    Ninety-six strains of Paenibacillus larvae, causative agent of American foulbrood in honey bee (Apis mellifera) larvae, collected from Connecticut, USA (CT), honey bees, and 12 P. larvae strains not from CT, were genotyped via ERIC-PCR and XbaI-RFLP analysis. All CT-isolates, five strains isolated in South America, three strains from North America (not CT), and one strain isolated in Australia grouped into the ERIC I genotype. Three P. larvae formerly subsp. pulvifaciens strains grouped into ERIC III and IV genotypes. XbaI-RFLP genotyping showed three genotypes within the CT-isolates, and two were identified as XbaI-RFLP Type I and III. The third XbaI-RFLP genotype (Type Ib) represented one of four new XbaI-RFLP genotypes identified. Comparison of genotype results for the P. larvae strains tested was used to develop a correlation between ERIC-PCR genotyping and XbaI-RFLP genotyping. Sixteen CT-isolates were tetracycline-resistant and demonstrated PCR amplification using oligonucleotide primers for tetL. All 16 isolates grouped within XbaI-RFLP Type Ib, suggesting limited introduction of a tetracycline-resistant strain into CT. PMID:25929327

  1. Developmental arrest in Caenorhabditis elegans dauer larvae causes high expression of enzymes involved in thymidylate biosynthesis, similar to that found in Trichinella muscle larvae.

    Science.gov (United States)

    Wińska, P; Gołos, B; Cieśla, J; Zieliński, Z; Fraczyk, T; Wałajtys-Rode, E; Rode, W

    2005-08-01

    Crude extract specific activities of thymidylate synthase, dUTPase, thymidine kinase and dihydrofolate reductase were high during the development of Caenorhabditis elegans, the dauer larva activities being similar to those previously determined in Trichinella spiralis and T. pseudospiralis muscle larvae (with the exception of thymidine kinase, not detected in Trichinella). High thymidylate synthase expression in developmentally arrested larvae, demonstrated also at the mRNA and protein levels, is in agreement with a global cell cycle arrest of dauer larvae and indicates this unusual cell cycle regulation pattern can be shared by developmentally arrested larvae of C. elegans and the two Trichnella species. Hence, the phenomenon may be characteristic for developmentally arrested larvae of different nematodes, rather than specific for the parasitic Trichinella muscle larvae. Endogenous C. elegans thymidylate synthase was purified and its molecular properties compared with those of the recombinant protein, expression of the latter in E. coli cells confirming the NCBI database sequence identity. PMID:16145941

  2. Paenibacillus larvae-Directed Bacteriophage HB10c2 and Its Application in American Foulbrood-Affected Honey Bee Larvae.

    Science.gov (United States)

    Beims, Hannes; Wittmann, Johannes; Bunk, Boyke; Spröer, Cathrin; Rohde, Christine; Günther, Gabi; Rohde, Manfred; von der Ohe, Werner; Steinert, Michael

    2015-08-15

    Paenibacillus larvae is the causative agent of American foulbrood (AFB), the most serious honey bee brood bacterial disease. We isolated and characterized P. larvae-directed bacteriophages and developed criteria for safe phage therapy. Whole-genome analysis of a highly lytic virus of the family Siphoviridae (HB10c2) provided a detailed safety profile and uncovered its lysogenic nature and a putative beta-lactamase-like protein. To rate its antagonistic activity against the pathogens targeted and to specify potentially harmful effects on the bee population and the environment, P. larvae genotypes ERIC I to IV, representatives of the bee gut microbiota, and a broad panel of members of the order Bacillales were analyzed for phage HB10c2-induced lysis. Breeding assays with infected bee larvae revealed that the in vitro phage activity observed was not predictive of the real-life scenario and therapeutic efficacy. On the basis of the disclosed P. larvae-bacteriophage coevolution, we discuss the future prospects of AFB phage therapy. PMID:26048941

  3. Fish larvae at fronts: Horizontal and vertical distributions of gadoid fish larvae across a frontal zone at the Norwegian Trench

    Science.gov (United States)

    Munk, Peter

    2014-09-01

    The reproduction and early life history of many fish species are linked to the physical and biological characteristics of fronts. In order to ascertain linkages between frontal physics and fish larvae, we investigated distributional differences among gadoid fish larvae comparing these to both horizontal and vertical variability in hydrography and abundances of potential copepod prey The investigation was carried out at a frontal zone along the Norwegian Trench in the northern North Sea, and was based on a series of cross-bathymetric sampling transects. Tows with a large ring net and an opening-closing net were used for describing fish larval horizontal and vertical distributions, while a submersible pump was used for describing vertical distributions of copepods. Hydrographic profiles and current velocity measurements were used to outline variability in temperature, salinity and current structure. Measurements demonstrated a distinct bottom front at the southern slope of the Trench with deepening isopycnals and high chlorphyll a concentrations. Abundances of both gadoid fish larvae and copepods peaked in vicinity of the front around mid-depth, and findings points to an inter-connection between the vertical and horizontal distributions of each species. However, the three-dimensional pattern of distribution differed significantly among species of larvae and species of copepods. The study underlines the complexity of bio-physical interrelationships in the frontal zone, and indicates that the zone encompasses specific ecological niches to which each species of fish larvae is adapted.

  4. Nutrient effects of broodstocks on the larvae in Patinopecten yessoensis

    Science.gov (United States)

    Bai, Yucen; Zhang, Tao; Qiu, Tianlong; Gao, Yan; Zhang, Xiaofang

    2015-07-01

    Patinopecten yessoensis is a commercial valuable species. This study deals with the effect of nutrient effects of the broodstock (mainly ovaries) on the larvae. Concentrations of total carbohydrate, total protein and total lipid in the gonads of P. yessoensis from three Hatcheries (Hatchery 1, Hatchery 2, and Hatchery 3) were determined before and after spawning. The relationship between the nutrient concentration in ovaries before spawning (BC) and that of larvae (LC) was assessed as well as the change in nutrient levels in ovaries after spawning (DC). Results indicate that the BC of total carbohydrate (7.66%) and total lipid (14.48%) in ovaries were significantly higher than in testes (5.20%, 5.20% respectively), whereas the BC of total protein in the ovaries was lower (61.76%) than in the testes (81.67%). The different gonadal composition suggests the different nutrient demands between male and female broodstocks in breeding season. Patinopecten yessoensis gonads contained a higher proportion of lipids, in comparison to other bivalves, which might be a response to the low ambient water temperatures. Further analysis of fatty acids showed that the concentrations of n-3PUFA, EPA and DHA in larvae (LC) were positively correlated with BC and DC, indicating the significant nutrient influence of broodstocks on the larvae. As these fatty acids are important in metabolism, and have been demonstrated to be influential to the viability of the larvae, larval growth and the settlement, spat growth, and juvenile survival in many bivalves, they could possibly be used as indexes to evaluate, and predict condition of broodstocks and larvae.

  5. Culture of Eriocheir sinensis Larvae in Ponds in Greenhouse

    Institute of Scientific and Technical Information of China (English)

    Guoliang RUAN; Liangcheng HU; Hai ZHOU; Dawen MA; Yabin TANG

    2016-01-01

    A total of 15 pools were selected from a greenhouse, and they were randomly and evenly divided into three groups. In each group, one stocking density of Eriocheir sinensis was arranged. The results showed that after 45-d culture, the crab number per kilogram reached about 300 with survival rate of about 20%; the initial stocking density had significantly effect on the body size of E. sinensis on sel , instead on the survival rate of E. sinensis larvae. Therefore, it is feasible to conduct the culture of E. sinensis larvae in a pool in greenhouse.

  6. A case report of cutaneous larva migrans in Argentina

    Institute of Scientific and Technical Information of China (English)

    Javier Bava; Lucia G Gonzalez; Celeste M Seley; Gisela P Lpez; Alcides Troncoso

    2011-01-01

    Cutaneous larva migrans (CLM) represents the most common tropically acquired dermatosis. CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas, and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it. The diagnosis is usually made on the basis of the typical appearance of the lesion, intense itching and history of foreign travel. CLM is a common parasitic skin disease that can be easily prevented by wearing 'protective' footwear. A case of CLM is described in this article.

  7. Sun-Compass Orientation in Mediterranean Fish Larvae

    OpenAIRE

    Robin Faillettaz; Agathe Blandin; Claire B. Paris; Philippe Koubbi; Jean-Olivier Irisson

    2015-01-01

    Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history , larvae of coastal species have to head back to the shore at the end of their pelagic episode , to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence of coast-related cues o...

  8. Catching large herring larvae: Gear applicability and larval distribution

    DEFF Research Database (Denmark)

    Munk, Peter

    1988-01-01

    third when speed was increased by one knot. The efficiency of the MIK did not change in the speed range investigated, and this gear was in every case more efficient than the IKMT. Larvae were found to be patchily distributed at the scale of sampling, and the degree of patchiness did not increase when...... stations 5 nm apart were compared. At night, herring larvae are confined to the 20-40-metre water layer, whereas a migration to upper water layers at dawn and dusk was observed....

  9. A case report of cutaneous larva migrans in Argentina

    Institute of Scientific and Technical Information of China (English)

    Javier; Bava; Lucia; G; Gonzalez; Celeste; M; Seley; Gisela; P; Lopez; Alcides; Troncoso

    2011-01-01

    Cutaneous larva migrans(CLM) represents the most common tropically acquired dermatosis.CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas,and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it.The diagnosis is usually made on the basis of the typical appearance of the lesion,intense itching and history of foreign travel.CLM is a common parasitic skin disease that can be easily prevented by wearing ’protective’ footwear.A case of CLM is described in this article.

  10. A case report of cutaneous larva migrans in Argentina

    OpenAIRE

    BAVA Javier; Gonzalez, Lucia G; Seley, Celeste M; López, Gisela P; Troncoso, Alcides

    2011-01-01

    Cutaneous larva migrans (CLM) represents the most common tropically acquired dermatosis. CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas, and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it. The diagnosis is usually made on the basis of the typical appearance of the lesion, intense itching and history of foreign travel. CLM is a common parasitic skin disease that can ...

  11. Intraguild predation and cannibalism among larvae of detritivorous caddisflies in subalpine wetlands

    Science.gov (United States)

    Wissinger, S.A.; Sparks, G.B.; Rouse, G.L.; Brown, W.S.; Steltzer, H.

    1996-01-01

    Comparative data from subalpine wetlands in Colorado indicate that larvae of the limnephilid caddisflies, Asynarchus nigriculus and Limnephilus externus, are reciprocally abundant among habitats - Limnephilus larvae dominate in permanent waters, whereas Asynarchus larvae dominate in temporary basins. The purpose of this paper is to report on field and laboratory experiments that link this pattern of abundance to biotic interactions among larvae. In the first field experiment, growth and survival were compared in single and mixed species treatments in littoral enclosures. Larvae, which eat mainly vascular plant detritus, grew at similar rates among treatments in both temporary and permanent habitats suggesting that exploitative competition is not important under natural food levels and caddisfly densities. However, the survival of Limnephilus larvae was reduced in the presence of Asynarchus larvae. Subsequent behavioral studies in laboratory arenas revealed that Asynarchus larvae are extremely aggressive predators on Limnephilus larvae. In a second field experiment we manipulated the relative sizes of larvae and found that Limnephilus larvae were preyed on only when Asynarchus larvae had the same size advantage observed in natural populations. Our data suggest that the dominance of Asynarchus larvae in temporary habitats is due to asymmetric intraguild predation (IGP) facilitated by a phenological head start in development. These data do not explain the dominance of Limnephilus larvae in permanent basins, which we show elsewhere to be an indirect effect of salamander predation. Behavioral observations also revealed that Asynarchus larvae are cannibalistic. In contrast to the IGP on Limnephilus larvae, Asynarchus cannibalism occurs among same-sized larvae and often involves the mobbing of one victim by several conspecifics. In a third field experiment, we found that Asynarchus cannibalism was not density-dependent and occurred even at low larval densities. We

  12. First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae, um ectosimbionte de larvas de Corydalidae (Maegaloptera

    Directory of Open Access Journals (Sweden)

    Susana Trivinho-Strixino

    2012-09-01

    Full Text Available First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera. This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalopteran larvae had 24 Temnocephala sp. associated. Furthermore, eight of these Temnocephala worms had chironomid larvae in their gut contents, an interaction previously unknown. Gut content analyses revealed Corynoneura as the commonest chironomid, but larvae of Larsia, Rheotanytarsus and Tanytarsus were recorded as well. This study included Corydalus and Protochauliodes as hosts for Temnocephala, which might be important for this worm dispersion and population dynamics.Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae, um ectosimbionte de larvas de Corydalidae (Maegaloptera. Este estudo constitui o primeiro registro de Temnocephala Blanchard (Platyhelminthes, Temnocephalidae, um ectosimbionte em larvas de Megaloptera, como um possível predador de larvas de Chironomidae. Vinte e oito larvas de Corydalidae (Corydalus e Protochauliodes foram examinadas sobre estereomicroscópio na busca por Temnocephala e larvas de Chironomidae, das quais cinco larvas de Megaloptera continham 24 Temnocephala sp. associadas. Além disso, oito Temnocephala possuíam em seu conteúdo estomacal larvas de Chironomidae, uma interação desconhecida anteriormente. A análise do conteúdo estomacal revelou Corynoneura como o quironomídeo mais abundante, e também algumas larvas de Larsia, Rheotanytarsus e Tanytarsus. Este estudo inclui Corydalus e Protochauliodes como hospedeiros de Temnocephala, os quais podem ser importantes

  13. Phage Therapy is Effective in Protecting Honeybee Larvae from American Foulbrood Disease.

    Science.gov (United States)

    Ghorbani-Nezami, Sara; LeBlanc, Lucy; Yost, Diane G; Amy, Penny S

    2015-01-01

    American foulbrood disease has a major impact on honeybees (Apis melifera) worldwide. It is caused by a Gram-positive, spore-forming bacterium, Paenibacillus larvae. The disease can only affect larval honeybees, and the bacterial endospores are the infective unit of the disease. Antibiotics are not sufficient to combat the disease due to increasing resistance among P. larvae strains. Because of the durability and virulence of P. larvae endospores, infections spread rapidly, and beekeepers are often forced to burn beehives and equipment. To date, very little information is available on the use of bacteriophage therapy in rescuing and preventing American foulbrood disease, therefore the goal of this study was to test the efficacy of phage therapy against P. larvae infection. Out of 32 previously isolated P. larvae phages, three designated F, WA, and XIII were tested on artificially reared honeybee larvae infected with P. larvae strain NRRL B-3650 spores. The presence of P. larvae DNA in dead larvae was confirmed by 16S rRNA gene-specific polymerase chain reaction amplification. Survival rates for phage-treated larvae were approximately the same as for larvae never infected with spores (84%), i.e., the phages had no deleterious effect on the larvae. Additionally, prophylactic treatment of larvae with phages before spore infection was more effective than administering phages after infection, although survival in both cases was higher than spores alone (45%). Further testing to determine the optimal combination and concentration of phages, and testing in actual hive conditions are needed. PMID:26136497

  14. Low-molecular-weight metabolites secreted by Paenibacillus larvae as potential virulence factors of American foulbrood.

    Science.gov (United States)

    Schild, Hedwig-Annabell; Fuchs, Sebastian W; Bode, Helge B; Grünewald, Bernd

    2014-04-01

    The spore-forming bacterium Paenibacillus larvae causes a severe and highly infective bee disease, American foulbrood (AFB). Despite the large economic losses induced by AFB, the virulence factors produced by P. larvae are as yet unknown. To identify such virulence factors, we experimentally infected young, susceptible larvae of the honeybee, Apis mellifera carnica, with different P. larvae isolates. Honeybee larvae were reared in vitro in 24-well plates in the laboratory after isolation from the brood comb. We identified genotype-specific differences in the etiopathology of AFB between the tested isolates of P. larvae, which were revealed by differences in the median lethal times. Furthermore, we confirmed that extracts of P. larvae cultures contain low-molecular-weight compounds, which are toxic to honeybee larvae. Our data indicate that P. larvae secretes metabolites into the medium with a potent honeybee toxic activity pointing to a novel pathogenic factor(s) of P. larvae. Genome mining of P. larvae subsp. larvae BRL-230010 led to the identification of several biosynthesis gene clusters putatively involved in natural product biosynthesis, highlighting the potential of P. larvae to produce such compounds. PMID:24509920

  15. Monthly variations of Rhinoestrus spp. (Diptera: Oestridae larvae infesting donkeys in Egypt: Morphological and molecular identification of third stage larvae

    Directory of Open Access Journals (Sweden)

    Mosaad A. Hilali

    2015-11-01

    Full Text Available This study was carried out to investigate the prevalence and monthly intensity of Rhinoestrus (R spp. among donkeys slaughtered at Giza Zoo abattoir, Egypt. A total of 144 donkeys were examined at postmortem through two visits per month from January 2010 to December 2010. All donkeys were infested with one or more larval stages during all months of the examination period (100%. The 1st and 2nd stage larvae (L1 and L2 were mostly observed in the turbinate bones and seldom in the nasal passages, whereas the 3rd stage larvae (L3 were observed mostly in ethmoid and lamina cribrosa and rarely in nasal passages and pharynx. The highest monthly intensity of infestation with the total number of larval stages was recorded in January and August, while the lowest occurred in September. L1 was observed during all months with two peaks in January and June. L2 occurred from February to April, July, and August. L3 was present from March to May, August, and September. The ranked size of infestation with the total number of the 3 larval stages of Rhinoestrus spp. showed that a total of 107 donkeys had 1–10 larvae; 34 had 11–30 larvae; and 3 harbored 31–50 larvae. The morphology and molecular characterization of the third stage larvae of Rhinoestrus spp. were investigated. Morphologically, two morphotypes (1 and 2 of Rhinoestrus spp. (R. usbekistanicus like and the other R. purpureus like were reported. Whereas molecular sequencing of mitochondrial cytochrome-oxidase subunit I showed 99% homology with those of R. usbekistanicus. In conclusion, Rhinoestrus spp. present in Egypt is mainly R. usbekistanicus, which includes two morphotypes, R. usbekistanicus like and R. purpureus like.

  16. The Blue Neck Syndrome : Nematode Larvae in Skin Scrapings

    Directory of Open Access Journals (Sweden)

    Sugathan P

    2000-01-01

    Full Text Available A novel non-inflammatory type of pigmentation of the neck associated with nematode larvae on affected skin is described. The name ′Blue neck syndrome′ is suggested for this condition because of the characteristic clinical appearance. Antinematode agents such as albendazole and neem oil have been found to be effective in the treatment.

  17. Lead levels of Culex mosquito larvae inhabiting lead utilizing factory

    Institute of Scientific and Technical Information of China (English)

    Kitvatanachai; S; Apiwathnasorn; C; Leemingsawat; S; Wongwit; W; Overgaard; HJ

    2011-01-01

    Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.

  18. Enantiomerization and enantioselective bioaccumulation of metalaxyl in Tenebrio molitor larvae.

    Science.gov (United States)

    Gao, Yongxin; Wang, Huili; Qin, Fang; Xu, Peng; Lv, Xiaotian; Li, Jianzhong; Guo, Baoyuan

    2014-02-01

    The enantiomerization and enantioselective bioaccumulation of metalaxyl by a single dose of exposure to Tenebrio molitor larvae under laboratory condition were studied by high-performance liquid chromatography tandem mass spectroscopy (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carbamate)] column. Exposure of enantiopure R-metalaxyl and S-metalaxyl in Tenebrio molitor larvae exhibited significant enantiomerization, with formation of the R enantiomers from the S enantiomers, and vice versa, which might be attributed to the chiral pesticide catalyzed by a certain enzyme in Tenebrio molitor larvae. Enantiomerization was not observed in wheat bran during the period of 21 d. In addition, bioaccumulation of rac-metalaxyl in Tenebrio molitor larvae was enantioselective with a preferential accumulation of S-metalaxyl. These results showed that enantioselectivity was caused not only by actual degradation and metabolism but also by enantiomerization, which was an important process in the environmental fate and behavior of metalaxyl enantiomers. PMID:24302540

  19. Symbiotic Bacteria Enable Olive Fly Larvae to Overcome Host Defenses

    International Nuclear Information System (INIS)

    Ripe fruit offer readily available nutrients for many animals, including fruit fly larvae (Diptera: Tephritidae) and their associated rot-inducing bacteria. Yet, during most of their ontogeny, fruit remain chemically defended and effectively suppress herbivores and pathogens by high levels of secondary metabolites. Olive flies (Bactrocera oleae) are uniquely able to develop in unripe olives. Unlike other frugivorous tephritids, the larvae maintain bacteria confined within their midgut caeca. We examined the interaction between larvae, their associated bacteria, and fruit chemical defence, hypothesizing that bacterial contribution to larval development is contingent on the phenology of fruit defensive chemistry. We demonstrate that larvae require their natural complement of bacteria (Candidatus Erwinia dacicola: Enterobacteriaceae) in order to develop in unripe olives. Conversely, when feeding on ripe fruit, larval development proceeds independently of these bacteria. Our experiments suggest that bacteria counteract the inhibitory effect of oleuropein—the principal phenolic glycoside in unripe olives. In light of these results, we suggest that the unique symbiosis in olive flies, compared with other frugivorous tephritids, is understood by considering the relationship between the fly, bacteria and fruit chemistry. When applied in an evolutionary context, this approach may also point out the forces which shaped symbioses across the Tephritidae. (author)

  20. Symbiotic bacteria enable olive fly larvae to overcome host defences.

    Science.gov (United States)

    Ben-Yosef, Michael; Pasternak, Zohar; Jurkevitch, Edouard; Yuval, Boaz

    2015-07-01

    Ripe fruit offer readily available nutrients for many animals, including fruit fly larvae (Diptera: Tephritidae) and their associated rot-inducing bacteria. Yet, during most of their ontogeny, fruit remain chemically defended and effectively suppress herbivores and pathogens by high levels of secondary metabolites. Olive flies (Bactrocera oleae) are uniquely able to develop in unripe olives. Unlike other frugivorous tephritids, the larvae maintain bacteria confined within their midgut caeca. We examined the interaction between larvae, their associated bacteria, and fruit chemical defence, hypothesizing that bacterial contribution to larval development is contingent on the phenology of fruit defensive chemistry. We demonstrate that larvae require their natural complement of bacteria (Candidatus Erwinia dacicola: Enterobacteriaceae) in order to develop in unripe olives. Conversely, when feeding on ripe fruit, larval development proceeds independently of these bacteria. Our experiments suggest that bacteria counteract the inhibitory effect of oleuropein-the principal phenolic glycoside in unripe olives. In light of these results, we suggest that the unique symbiosis in olive flies, compared with other frugivorous tephritids, is understood by considering the relationship between the fly, bacteria and fruit chemistry. When applied in an evolutionary context, this approach may also point out the forces which shaped symbioses across the Tephritidae. PMID:26587275

  1. Nonlinear ecological processes driving the distribution of marine decapod larvae

    Science.gov (United States)

    Peña, M.; Carbonell, A.; Tor, A.; Alvarez-Berastegui, D.; Balbín, R.; dos Santos, A.; Alemany, F.

    2015-03-01

    The complexity of the natural processes lead to many nonlinear interacting factors that influence the distribution and survival of marine pelagic species, particularly in their larval phase. The management of these ecosystems requires techniques that unveil those interactions by studying the system globally, including all relevant variables and combining both community and environmental data in a single step. Specifically, we apply an unsupervised neural network, the Self-Organising Map (SOM), to a combined dataset of environmental and decapod larvae community data from the Balearic sea, obtained in two years with contrasting environmental scenarios, as an Exploratory Data Analysis (EDA) technique that provides a global and more detailed view of both the environmental processes and their influence on the distribution of such planktonic community. We examine the parental influence on the initial larval distribution by aggregating data by adult habitat, which also increments the signal to noise ratio (mean data patterns over noise due to outliers or measurement errors), and consider the distribution of larvae by development stage (as a proxy of age and hence of potential dispersion). The joined study of parental effect, drifting or concentration events determined by dynamical processes in the whole water column, and lifespan, draws the possible paths followed by larvae, and highlights the more influencing variables in their distribution. Investigation of the different aspects of dynamic height (absolute values, gradients or edges and correlations) clarified the effect of the oceanographic processes on decapods' larvae.

  2. Skeletogenesis in sea urchin larvae under modified gravity conditions

    Science.gov (United States)

    Marthy, H.-J.; Gasset, G.; Tixador, R.; Eche, B.; Schatt, P.; Dessommes, A.; Marthy, U.; Bacchieri, R.

    From many points of view, skeletogenesis in sea urchins has been well described. Based on this scientific background and considering practical aspects of sea urchin development (i.e. availability of material, size of larvae, etc.), we wanted to know whether orderly skeletogenesis requires the presence of gravity. The objective has been approached by three experiments successfully performed under genuine microgravity conditions (in the STS-65 IML-2 mission of 1994; in the Photon-10 IBIS mission of 1995 and in the STS-76 S/MM-03 mission of 1996). Larvae of the sea urchin Sphaerechinus granularis were allowed to develop in microgravity conditions for several days from blastula stage onwards (onset of skeletogenesis). At the end of the missions, the recovered skeletal structures were studied with respect to their mineral composition, architecture and size. Live larvae were also recovered for post-flight culture. The results obtained clearly show that the process of mineralisation is independent of gravity: that is, the skeletogenic cells differentiate correctly in microgravity. However, abnormal skeleton architectures were encountered, particularly in the IML-2 mission, indicating that the process of positioning of the skeletogenic cells may be affected, directly or indirectly, by environmental factors, including gravity. Larvae exposed to microgravity from blastula to prism/early pluteus stage for about 2 weeks (IBIS mission), developed on the ground over the next 2 months into normal metamorphosing individuals.

  3. Genome Sequences of Six Paenibacillus larvae Siphoviridae Phages.

    Science.gov (United States)

    Carson, Susan; Bruff, Emily; DeFoor, William; Dums, Jacob; Groth, Adam; Hatfield, Taylor; Iyer, Aruna; Joshi, Kalyani; McAdams, Sarah; Miles, Devon; Miller, Delanie; Oufkir, Abdoullah; Raynor, Brinkley; Riley, Sara; Roland, Shelby; Rozier, Horace; Talley, Sarah; Miller, Eric S

    2015-01-01

    Six sequenced and annotated genomes of Paenibacillus larvae phages isolated from the combs of American foulbrood-diseased beehives are 37 to 45 kbp and have approximately 42% G+C content and 60 to 74 protein-coding genes. Phage Lily is most divergent from Diva, Rani, Redbud, Shelly, and Sitara. PMID:26089405

  4. The Colonization Dynamics of the Gut Microbiota in Tilapia Larvae

    NARCIS (Netherlands)

    Giatsis, C.; Sipkema, D.; Smidt, H.; Verreth, J.A.J.; Verdegem, M.C.J.

    2014-01-01

    The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an e

  5. Insect Larvae: A New Platform to Produce Commercial Recombinant Proteins.

    Science.gov (United States)

    Targovnik, Alexandra M; Arregui, Mariana B; Bracco, Lautaro F; Urtasun, Nicolas; Baieli, Maria F; Segura, Maria M; Simonella, Maria A; Fogar, Mariela; Wolman, Federico J; Cascone, Osvaldo; Miranda, Maria V

    2016-01-01

    In Biotechnology, the expression of recombinant proteins is a constantly growing field and different hosts are used for this purpose. Some valuable proteins cannot be produced using traditional systems. Insects from the order Lepidoptera infected with recombinant baculovirus have appeared as a good choice to express high levels of proteins, especially those with post-translational modifications. Lepidopteran insects, which are extensively distributed in the world, can be used as small protein factories, the new biofactories. Species like Bombyx mori (silkworm) have been analyzed in Asian countries to produce a great number of recombinant proteins for use in basic and applied science and industry. Many proteins expressed in this larva have been commercialized. Several recombinant proteins produced in silkworms have already been commercialized. On the other hand, species like Spodoptera frugiperda, Heliothis virescens, Rachiplusia nu, Helicoverpa zea and Trichoplusia ni are widely distributed in both the occidental world and Europe. The expression of recombinant proteins in larvae has the advantage of its low cost in comparison with insect cell cultures. A wide variety of recombinant proteins, including enzymes, hormones and vaccines, have been efficiently expressed with intact biological activity. The expression of pharmaceutically proteins, using insect larvae or cocoons, has become very attractive. This review describes the use of insect larvae as an alternative to produce commercial recombinant proteins. PMID:26956108

  6. The potential for ontogenetic vertical migration by larvae of bathyal echinoderms

    OpenAIRE

    Young, Cm; Devin, Mg; Jaeckle, Wb; Ekaratne, Suk; George, Sb

    1996-01-01

    Planktotrophy is a relatively common developmental mode among bathyal and abyssal echinoderms, but the sources of food used by deep-sea planktotrophic larvae remain generally unknown. Very few deep-sea echinoderm larvae have been collected in plankton samples, so we do not know whether larvae migrate to the euphotic zone to feed or if they rely on bacteria or detritus at greater depths. We approached this question indirectly by investigating whether larvae of bathyal echinoids can tolerate th...

  7. S1 guideline diagnosis and therapy of cutaneous larva migrans (creeping disease)

    OpenAIRE

    Sunderkötter, C.; von Stebut, E.; Schöfer, H.; Mempel, M; Reinel, D; Wolf, G.; Meyer, V.; Nast, A; Burchard, GD

    2014-01-01

    Cutaneous larva migrans is a skin infection with a typical clinical appearance caused by active penetration of nematode larvae and their subsequent epidermal migration. The typical clinical appearance is caused by hookworm larvae, usually Ancylostoma braziliense but sometimes other canine or feline types of hookworm.This guideline aims to enhance patient care by optimizing the diagnosis and treatment of infections due to creeping disease (cutaneous larva migrans) and to raise awareness among ...

  8. Interrelationships among egg, larvae and maternal characteristics in Persian sturgeon Acipenser persicus

    OpenAIRE

    Rajab Mohammad Nazari; Mohammad Reza Ghomi; Laura Aquiloni

    2010-01-01

    This study was aimed to observe the correlations among egg, larvae and maternal characteristics of Persian sturgeon. A total of 41 females were used and the variables including fertilization rate, incubation survival rate, larvae survival rate during yolk sac absorption (before feeding), and larvae survival rate after first feeding were determined. As a result, fertilization rate was positively correlated with three variables: incubation survival, larvae survival during yolk sac absorption, a...

  9. Predation on anchovy larvae by a pelagic chaetognatha, Sagitta nagae in the Sagami Bay, central Japan

    OpenAIRE

    Terazaki, Makoto

    2005-01-01

    Anchovy larvae were detected in the gut of Sagitta nagae collected near Oshima Island in Sagami Bay during the night on 23 May 1996. S. nagae attacked the anchovy larvae actively when they encountered the aggregation of larvae. Generally, large animals consumed larger prey and there is a good correlation between body length of S. nagae and their prey size. Many S. nagae caught anchovy larvae from tail.

  10. Monitoring tectal neuronal activities and motor behavior in zebrafish larvae.

    Science.gov (United States)

    Sumbre, Germán; Poo, Mu-Ming

    2013-09-01

    To understand how visuomotor behaviors are controlled by the nervous system, it is necessary to monitor the activity of large populations of neurons with single-cell resolution over a large area of the brain in a relatively simple, behaving organism. The zebrafish larva, a small lower vertebrate with transparent skin, serves as an excellent model for this purpose. Immediately after the larva hatches, it needs to catch prey and avoid predators. This strong evolutionary pressure leads to the rapid development of functional sensory systems, particularly vision. By 5 d postfertilization (dpf), tectal cells show distinct visually evoked patterns of activation, and the larvae are able to perform a variety of visuomotor behaviors. During the early larval stage, zebrafish breathe mainly through the skin and can be restrained under the microscope using a drop of low-melting-point agarose, without the use of anesthetics. Moreover, the transparency of the skin, the small diameter of the neurons (4-5 µm), and the high-neuronal density enable the use of in vivo noninvasive imaging techniques to monitor neuronal activities of up to ∼500 cells within the central nervous system, still with single-cell resolution. This article describes a method for simultaneously monitoring spontaneous and visually evoked activities of large populations of neurons in the optic tectum of the zebrafish larva, using a synthetic calcium dye (Oregon Green BAPTA-1 AM) and a conventional confocal or two-photon scanning fluorescence microscope, together with a method for measuring the tail motor behavior of the head-immobilized zebrafish larva. PMID:24003199

  11. Feeding habits of Chironomidae larvae (Insecta: Diptera in Vargem Limpa stream, Bauru, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel Lucas Bochini

    2008-06-01

    Full Text Available The present study analyzed the feeding habits and structure of the Chironomidae fauna in Vargem Limpa stream, in December 2004. The main food item ingested by most of the analyzed genera (Beardius, Caladomyia, Chironomus, Clinotanypus, Corynoneura, Cricotopus, Cryptochironomus, Dicrotendipes, Endotribelos, Harnischia, Fissimentum, Lopescladius, Polypedilum, Tanypus and Tanytarsus was identified as detritus, except for the Cladopelma whose main food item was algae. Ablabesmyia was the only genus that exhibited items of animal origin in the diet. The diets of 17 genera were investigated, and the majority of the individuals were classified as collectors.

  12. Agathomerus (Agathomeroides flavomaculatus (Coleoptera, Megalopodidae, Megalopodinae: morfologia da larva e do adulto Agathomerus (Agathomeroides flavomaculatus (Coleoptera, Megalopodidae, Megalopodinae: larva and adult morphology

    Directory of Open Access Journals (Sweden)

    Elisa B. Carvalho

    Full Text Available A larva de Agathomerus (Agathomeroides flavomaculatus (Klug, 1824, coletada em Capsicum baccatum L. (Solanaceae, é descrita e ilustrada. A redescrição do adulto inclui caracteres das peças bucais, venação da asa, endosternitos e terminálias masculina e feminina. Pela primeira vez uma larva da subfamília Megalopodinae é descrita.The larva of Agathomerus (Agathomeroides flavomaculatus (Klug, 1824, collected in Capsicum baccatum L. (Solanaceae, is described and illustrated. The adult redescription includes characters of mouthparts, wing venation, endosternites and male and female terminalia. For the first time a larva of subfamily Megalopodinae is described.

  13. Feeding habits of Pacific cod larvae and juveniles in Mutsu Bay, Japan

    OpenAIRE

    Takatsu, Tetsuya; Nakatani, Toshikuni; MUTOH, Takashi; Takahashi, Toyomi

    1995-01-01

    The diets and prey widths of Pacific cod (Gadus macrocephalus) larvae and juveniles were examined in Mutsu Bay. In early March, 11 yolk-sac larvae were caught in midwater of the bay mouth. Five of 11 larvae captured had not opened their mouths, and the remaining six had not fed. Post-larvae ≤ 7mm in total length (TL) fed on copepod nauplii, particularly Pseudocalanus nauplii. Prey items of post-larvae >7mm TL were chiefly crustacean eggs, and Pseudocalanus spp. copepodites and adults. From Ap...

  14. Age of Atlantic halibut larvae (Hippoglossus hippoglossus L.) at first feeding

    OpenAIRE

    Harboe, Torstein; Næss, Tore Håkon; Naas, Kjell Emil; Rabben, Håvard; Skjolddal, Lillian

    1990-01-01

    Halibut larvae at different age (150 to 315 day-degrees) were transferred to outdoor startfeeding tanks each with two internal plastic bags (100 litre). The larvae were fed wild zooplankton. One bag was sampled after 24 hours, and the other after nine days. Numbers of larvae with food in the gut, without food in gut and dead larvae, were counted for each larval age tested. The results showed that some larvae captured prey at an age of 150 day-degrees. However, at this age few ...

  15. [Ingestion and digestion of seven species of microalgae by larvae of Strombus gigas (Mesogastropoda: Strombidae)].

    Science.gov (United States)

    Patiño Súarez, V; Aldana Aranda, D

    2000-12-01

    The potential nutritional value of seven microalgal diets as measured by their ingestibility and digestibility to queen conch Strombus gigas larvae was tested with 30 day old larvae reared at 28 degrees C and fed at 1000 cells x ml(-1). The algae were Tetraselmis suecica, Tetraselmis chuii Isochrysis aff. galbana, Dunaliella tertiolecta, Chlamydomonas coccoides, Chaetoceros sp. and Thalassiosira fluviatilis. Ingestion and digestion were measured by the four nutritional stages studied with epifluorescence microscopy with live larvae. Temporal and absolute indices showed that larvae fed Chaetoceros sp. and T. fluviatilis had lower ingestion and digestion levels. The other algae are recommend to feed S. gigas larvae. PMID:15266796

  16. Reduction of muscle larvae burden in rats experimentally infected with Trichinella spiralis

    Directory of Open Access Journals (Sweden)

    Machnicka-Rowinska B.

    2001-06-01

    Full Text Available In Wistar rats infected with 500 to 2,500 Trichinella spiralis larvae the muscle larvae intensity (larvae per gram-l.p.g. was measured from 20 to 180 day post infection (d.p.i. The l.p.g. increased to day 40-50 p.i. and decreased thereafter. The highest reduction took place between 6 0 and 120 d.p.i. with intermediate inoculum of T. spiralis larvae. The mechanism of the reduction of T. spiralis larvae in muscles is suggested to depend on pericapsular-intercapsular host cells infiltrations attracted by parasite antigens.

  17. Validation and efficacy of transgenerational mass marking of otoliths in viviparous fish larvae.

    Science.gov (United States)

    Kuroki, M; Buckley, R M; Leclair, L L; Hauser, L

    2010-07-01

    Transgenerational mass marking of viviparous fish larvae in vivo was validated by intra-muscular injection of elemental strontium chloride (SrCl(2)) in gestating females and detection of the Sr in the otoliths of developing larvae. All otoliths of brown rockfish Sebastes auriculatus larvae produced from SrCl(2)-injected females showed enriched Sr:Ca ratios near the otolith edges, and the signatures did not appear to be affected by the anterior, centre and posterior positions of larvae within the ovary. Results from the present study indicate that transgenerational marking is a highly reliable technique for marking large numbers of extremely small viviparous fish larvae. PMID:20646154

  18. Description of the larva of Gynacantha millardi Selys, 1891 (Odonata: Aeshnidae) from Chhattisgarh, India.

    Science.gov (United States)

    Dawn, Prosenjit; Chandra, Kailash

    2016-01-01

    The larva of Gynacantha millardi Selys is described here from female larvae and male and female exuviae collected from Chhattisgarh, India. Unlike other Gynacantha larvae known so far, G. millardi has 7 palpal setae almost equal in length; in other species, the palpal setae are of different lengths. The larvae lack a tooth on each side of the median cleft and have a distinct blunt tooth on the inner margin corner of each labial palp. The larvae were found in a semi-stagnant forest pool with enormous growth of aquatic vegetation. PMID:27395672

  19. Multi-scale approach to the environmental factors effects on spatio-temporal variability of Chironomus salinarius (Diptera: Chironomidae) in a French coastal lagoon

    Science.gov (United States)

    Cartier, V.; Claret, C.; Garnier, R.; Fayolle, S.; Franquet, E.

    2010-03-01

    The complexity of the relationships between environmental factors and organisms can be revealed by sampling designs which consider the contribution to variability of different temporal and spatial scales, compared to total variability. From a management perspective, a multi-scale approach can lead to time-saving. Identifying environmental patterns that help maintain patchy distribution is fundamental in studying coastal lagoons, transition zones between continental and marine waters characterised by great environmental variability on spatial and temporal scales. They often present organic enrichment inducing decreased species richness and increased densities of opportunist species like C hironomus salinarius, a common species that tends to swarm and thus constitutes a nuisance for human populations. This species is dominant in the Bolmon lagoon, a French Mediterranean coastal lagoon under eutrophication. Our objective was to quantify variability due to both spatial and temporal scales and identify the contribution of different environmental factors to this variability. The population of C. salinarius was sampled from June 2007 to June 2008 every two months at 12 sites located in two areas of the Bolmon lagoon, at two different depths, with three sites per area-depth combination. Environmental factors (temperature, dissolved oxygen both in sediment and under water surface, sediment organic matter content and grain size) and microbial activities (i.e. hydrolase activities) were also considered as explanatory factors of chironomid densities and distribution. ANOVA analysis reveals significant spatial differences regarding the distribution of chironomid larvae for the area and the depth scales and their interaction. The spatial effect is also revealed for dissolved oxygen (water), salinity and fine particles (area scale), and for water column depth. All factors but water column depth show a temporal effect. Spearman's correlations highlight the seasonal effect

  20. Starving honey bee (Apis mellifera) larvae signal pheromonally to worker bees

    Science.gov (United States)

    He, Xu Jiang; Zhang, Xue Chuan; Jiang, Wu Jun; Barron, Andrew B.; Zhang, Jian Hui; Zeng, Zhi Jiang

    2016-01-01

    Cooperative brood care is diagnostic of animal societies. This is particularly true for the advanced social insects, and the honey bee is the best understood of the insect societies. A brood pheromone signaling the presence of larvae in a bee colony has been characterised and well studied, but here we explored whether honey bee larvae actively signal their food needs pheromonally to workers. We show that starving honey bee larvae signal to workers via increased production of the volatile pheromone E-β-ocimene. Analysis of volatile pheromones produced by food-deprived and fed larvae with gas chromatography-mass spectrometry showed that starving larvae produced more E-β-ocimene. Behavioural analyses showed that adding E-β-ocimene to empty cells increased the number of worker visits to those cells, and similarly adding E-β-ocimene to larvae increased worker visitation rate to the larvae. RNA-seq and qRT-PCR analysis identified 3 genes in the E-β-ocimene biosynthetic pathway that were upregulated in larvae following 30 minutes of starvation, and these genes also upregulated in 2-day old larvae compared to 4-day old larvae (2-day old larvae produce the most E-β-ocimene). This identifies a pheromonal mechanism by which brood can beg for food from workers to influence the allocation of resources within the colony. PMID:26924295

  1. Starving honey bee (Apis mellifera) larvae signal pheromonally to worker bees.

    Science.gov (United States)

    He, Xu Jiang; Zhang, Xue Chuan; Jiang, Wu Jun; Barron, Andrew B; Zhang, Jian Hui; Zeng, Zhi Jiang

    2016-01-01

    Cooperative brood care is diagnostic of animal societies. This is particularly true for the advanced social insects, and the honey bee is the best understood of the insect societies. A brood pheromone signaling the presence of larvae in a bee colony has been characterised and well studied, but here we explored whether honey bee larvae actively signal their food needs pheromonally to workers. We show that starving honey bee larvae signal to workers via increased production of the volatile pheromone E-β-ocimene. Analysis of volatile pheromones produced by food-deprived and fed larvae with gas chromatography-mass spectrometry showed that starving larvae produced more E-β-ocimene. Behavioural analyses showed that adding E-β-ocimene to empty cells increased the number of worker visits to those cells, and similarly adding E-β-ocimene to larvae increased worker visitation rate to the larvae. RNA-seq and qRT-PCR analysis identified 3 genes in the E-β-ocimene biosynthetic pathway that were upregulated in larvae following 30 minutes of starvation, and these genes also upregulated in 2-day old larvae compared to 4-day old larvae (2-day old larvae produce the most E-β-ocimene). This identifies a pheromonal mechanism by which brood can beg for food from workers to influence the allocation of resources within the colony. PMID:26924295

  2. Enhanced ammonia content in compost leachate processed by black soldier fly larvae.

    Science.gov (United States)

    Green, Terrence R; Popa, Radu

    2012-03-01

    Black soldier fly (BSF) larvae (Hermetia illucens), feeding on leachate from decaying vegetable and food scrap waste, increase ammonia (NH (4) (+) ) concentration five- to sixfold relative to leachate unprocessed by larvae. NH (4) (+) in larva-processed leachate reached levels as high as ∼100 mM. Most of this NH (4) (+) appears to have come from organic nitrogen within the frass produced by the larvae as they fed on leachate. In nitrate-enriched solutions, BSF larvae also facilitate dissimilatory nitrate reduction to ammonia. The markedly higher concentration of NH (4) (+) recovered in leachates processed with BSF larvae and concomitant diversion of nutrients into insect biomass (itself a valuable feedstock) indicate that the use of BSF larvae in processing leachate of decaying organic waste could be advantageous in offsetting capital and environmental costs incurred in composting. PMID:22238016

  3. VISCERAL LARVA MIGRANS AND TROPICAL PYOMYOSITIS: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Roberto LAMBERTUCCI

    1998-11-01

    Full Text Available We report a case of tropical pyomyositis in a boy who presented with a severe febrile illness associated with diffuse erythema, and swelling in many areas of the body which revealed on operation extensive necrotic areas of various muscles that required repeated débridement. The patient gave a history of contact with dogs, and an ELISA test for Toxocara canis was positive. He also presented eosinophilia and high serum IgE levels. Staphylococcus aureus was the sole bacteria isolated from the muscles affected. We suggest that tropical pyomyositis may be caused by the presence of migrating larvae of this or other parasites in the muscles. The immunologic and structural alterations caused by the larvae, in the presence of concomitant bacteremia, would favour seeding of the bacteria and the development of pyomyositis.

  4. EFFICACY OF THAI NEEM OIL AGAINST AEDES AEGYPTI (L.) LARVAE.

    Science.gov (United States)

    Silapanuntakul, Suthep; Keanjoom, Romnalin; Pandii, Wongdyan; Boonchuen, Supawadee; Sombatsiri, Kwanchai

    2016-05-01

    Trees with larvicidal activity may be found in Thailand. We conducted this study to evaluate the efficacy and length of efficacy of Thai neem (Azadirachta siamensis) oil emulsion and an alginate bead of Thai neem oil formulation against early fourth stage Aedes aegypti larvae using a dipping test. The Thai neem oil emulsion had significantly greater larvicidal activity than the alginate bead formulation at 12 to 60 hours post-exposure (p neem oil formulation resulted in 100% mortality among the early fourth stage Aedes aegypti larvae at 48 hours, while the alginate bead formulation resulted in 98% larval mortality at 84 hours and 100% mortality at 96 hours. The mean larval mortality using the Thai neem oil emulsion dropped to < 25% by 12 days and with the alginate beads dropped to < 25% by 15 days of exposure. PMID:27405123

  5. Tracking radioactive larvae of Strongyloides ratti in the host

    International Nuclear Information System (INIS)

    Infective larvae of homogonic Strongyloides ratti grown in faecal culture with 32P or 75Se acquired a significant amount of radioactivity which was firmly attached to them. Heating removed most of the 32P but left 75Se in place. Subcutaneous injection of virgin and nursing mother rats with living and heat-killed ratioactive larvae resulted in a pattern of labelling in the small intestine of injected animals and, in the case of 75Se, those of suckling pups, which can only be explained if labelled worms follow the natural migratory routes. The use of this tool in migratory studies is discussed, with precautions to allow for flaws in the technique. (author)

  6. Identification of common excitatory motoneurons in Drosophila melanogaster larvae.

    Science.gov (United States)

    Takizawa, Eiji; Komatsu, Akira; Tsujimura, Hidenobu

    2007-05-01

    In insects, four types of motoneurons have long been known, including fast motoneurons, slow motoneurons, common inhibitory motoneurons, and DUM neurons. They innervate the same muscle and control its contraction together. Recent studies in Drosophila have suggested the existence of another type of motoneuron, the common excitatory motoneuron. Here, we found that shakB-GAL4 produced by labels this type of motoneuron in Drosophila larvae. We found that Drosophila larvae have two common excitatory motoneurons in each abdominal segment, RP2 for dorsal muscles and MNSNb/d-Is for ventral muscles. They innervate most of the internal longitudinal or oblique muscles on the dorsal or ventral body wall with type-Is terminals and use glutamate as a transmitter. Electrophysiological recording indicated that stimulation of the RP2 axon evoked excitatory junctional potential in a dorsal muscle. PMID:17867850

  7. Immunogenic effects of irradiated Haemonchus contortus larvae in goats

    International Nuclear Information System (INIS)

    Development of radiation-attenuated vaccines against parasitic disease has been reported in literature. Use of irradiated larvae as vaccines enables advantage to be taken of the special immunological properties of living parasites; radiation treatment can largely suppress the pathogenic effects of the vaccines and the reproductive capacity of the parasites involved. Attempts to produce a radiation-attenuated vaccine against Haemonchus contortus infection in adult goats are discussed here. H. contortus infection in ruminants is prevalent in the Philippines, especially among cattle and goats. The results presented indicate that a certain degree of resistance against H. contortus infection can be induced in adult goats immunized with irradiated larvae. The shelf-life of the vaccine was also determined. (author)

  8. Microvascular system forming in skeletal muscle near trichinella larvae

    International Nuclear Information System (INIS)

    The fine structure and dynamics of formation of the microcirculatory system about the larvae of the two Trichinella species, providing for the rapid entry of nutrient substances to the larvae, were investigated in the muscles of white mice. Hitological, hitochemical, autoradiographic, and electron-microscopic methods were used in the investigation. At a certain period of the experiment, the greatest quantity of RNA was found in the endotheliocyte cytoplasm, tritium-thymidine label was incorporated into the nuclei, and mitoses were visible. The transition to tissue parasitism was accompanied by a complication of the relationships with the host and the formation of a more complex independent microcirculatory system, which ensures a more intensive influx of blood

  9. Maya Index and Larva Density Aedes Aegypti Toward Dengue Infection

    Directory of Open Access Journals (Sweden)

    Sang G. Purnama

    2012-12-01

    Full Text Available South Denpasar District was of there as with the highest dengue cases in Bali province. The number of mosquito breeding places and larvae density become risk factor that influenced the spreading of mosquitoes. Maya index was an indicator to measure the amount of waterreservoirs can be breeding places for mosquitoes. Knowing the relationship between maya index and density of larvae and pupae of Ae.aegypti toward dengue infection in South Denpasar District. The study was observational analytic with case-control design. Data was collected through interviews and field observations to 150 respondents. The survey entomologist with indicators maya index, house index (HI, container index (CI, breteau index (BI and pupa index (PI to see the density of larvae and pupae in survey area. Dengue transmission risk was categorized mild, moderate and severe based on density figure. Water storage containers inspected in 1215 containers that as many as 675 containers in the case and 540 containers in control. Water reservoirs (TPA that the most larvae was tub (29.27%, dispenser (18.29%, container tirta (10.98%, wells (10.98%. Maya index status was lower in the case (24% smaller thancontrols (37.33%. Value of HI = 23.33; CI=10.69; BI=55; PI=15.33. Based on HI and CI indicator South Denpasar District means have moderate the risk of transmission spread of dengue disease. Based on the BI, have a high risk of transmission to the spread of dengue disease. Based on the maya index showed house cases have highest risk as breeding place compare than control house. House index, Breteau index, container index, pupa index and maya index have correlation with dengue infection. Kind of breeding place have the high risk is bath tub

  10. What do barnacle larvae feed on ? Implications in biofouling ecology

    Digital Repository Service at National Institute of Oceanography (India)

    Gaonkar, C.; Anil, A.C.

    (Figure 5). Analysis of variance also indicated a significant variation in barnacle recruitment among different sampling months (ANOVA: p≤0.05). DISCUSSION The mode of nutrition in larval forms plays an important role in their capability..., though the larvae raised in the microcosm experienced nutritional stress which was shown by lower ratios of RNA: DNA (Desai & Anil, 2002). This study further indicates their capability to feed on food materials other than diatoms. As the fecal...

  11. Endogenous Dopamine Suppresses Initiation of Swimming in Prefeeding Zebrafish Larvae

    OpenAIRE

    Thirumalai, Vatsala; Cline, Hollis T.

    2008-01-01

    Dopamine is a key neuromodulator of locomotory circuits, yet the role that dopamine plays during development of these circuits is less well understood. Here, we describe a suppressive effect of dopamine on swim circuits in larval zebrafish. Zebrafish larvae exhibit marked changes in swimming behavior between 3 days postfertilization (dpf) and 5dpf. We found that swim episodes were fewer and of longer durations at 3 than at 5dpf. At 3dpf, application of dopamine as well as bupropion, a dopamin...

  12. Recording field potentials from zebrafish larvae during escape responses.

    Science.gov (United States)

    Monesson-Olson, Bryan D; Troconis, Eileen L; Trapani, Josef G

    2014-01-01

    Among vertebrates, startle responses are a ubiquitous method for alerting, and avoiding or escaping from alarming or dangerous stimuli. In zebrafish larvae, fast escape behavior is easily evoked through either acoustic or tactile stimuli. For example, a light touch to the head will excite trigeminal neurons that in turn excite a large reticulospinal neuron in the hindbrain called the Mauthner cell (M-cell). The M-cell action potential then travels down the contralateral trunk of the larva exciting motoneurons, which subsequently excite the entire axial musculature, producing a large amplitude body bend away from the source of the stimulus. This body conformation is known as the "C-bend" due to the shape of the larva during the behavior. As a result of the semi-synchronized activation of the M-cell, the population of motor neurons, and the axial trunk muscles, a large field potential is generated and can be recorded from free-swimming or fixed-position larvae. Undergraduate laboratories that record field potentials during escape responses in larval zebrafish are relatively simple to setup and allow students to observe and study the escape reflex circuit. Furthermore, by testing hypotheses, analyzing data and writing journal-style laboratory reports, students have multiple opportunities to learn about many neuroscience topics including vertebrate reflexes; sensory transduction; synaptic-, neuro-, and muscle-physiology; the M-cell mediated escape response; and the zebrafish as a model organism. Here, we detail the equipment, software, and recording setup necessary to observe field potentials in an undergraduate teaching lab. Additionally, we discuss potential advanced laboratory exercises and pedagogical outcomes. Finally, we note possible low-cost alternatives for recording field potentials. PMID:25565920

  13. Larva currens in a case of Organophosphorous poisoning

    Directory of Open Access Journals (Sweden)

    Rao D

    2006-01-01

    Full Text Available A 20-year-old healthy farmer consumed organophosphorous poison. On third day he developed diarrhoea and on fourth day linear serpiginous ulcers appeared on both buttocks. Clinically lesions were considered as decubitus ulcers. By stool examination and other laboratory investigations it was diagnosed as cutaneous larva currens due to S trongyloides stercoralis in a case of organophosphorus poisoning. Patient responded very well to a course of albendazole.

  14. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae)

    OpenAIRE

    Lilian Cristina Macedo; Francisco Tiago de Vasconcelos Melo; Teresa Cristina Sauer Ávila-Pires; Elane Guerreiro Giese; Jeannie Nascimento dos Santos

    2016-01-01

    Abstract Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the “Osvaldo Rodrigues da Cunha” Herpetolog...

  15. KARAKTERISTIK TEMPAT PERKEMBANGBIAKAN DAN DENSITAS LARVA ANOPHELES SUBPICTUS KABUPATEN BULUKUMBA

    OpenAIRE

    Faatimah, Dewi; Ishak, Hasanuddin; Selomo, Makmur

    2015-01-01

    Kabupaten Bulukumba merupakan salah satu daerah endemis malaria yang ada di Sulawesi Selatan dengan angka kesakitan (api) per 1.000 penduduk dengan 11 kasus (API 0,47???) tahun 2013. Penelitian ini bertujuan untuk mengatahui gambaran densitas larva Anopheles subpictus dan Anopheles barbirostis berdasarkan suhu, pH, salinitas, dan jenis vegetasi air yang ada. Jenis penelitian ini adalah penelitian observasional dengan pendekatan deskritif. Sampel tempat perindukan dalam penelitian ini termasu...

  16. Suscetibilidade de larvas de Culex quinquefasciatus a diferentes inseticidas

    Directory of Open Access Journals (Sweden)

    Stênio Nunes Alves

    2011-08-01

    Full Text Available INTRODUÇÃO: O presente estudo teve como objetivo avaliar a suscetibilidade de larvas de Culex quinquefasciatus a dois piretróides (Cipermetrina e Deltametrina, dois derivados da Avermectina (ivermectina e abamectina e a um organofosforado (Temefós. MÉTODOS: Larvas de 3º e 4º instares de C. quinquefasciatus foram expostas a diferentes concentrações destes (onze repetições seguindo o protocolo da Organização Mundial de Saúde. Uma hora após a exposição, as larvas foram lavadas em água desclorada, transferidas para recipientes plásticos contendo água sem cloro, alimentadas e observadas por períodos de 24h, até se transformarem em adultos. Para a determinação das concentrações letais, os valores foram submetidos à análise de regressão usando o modelo probit pelo programa Minitab 15. RESULTADOS: Diferenças entre as estimativas da CL50 e CL90 justificaram que a população de mosquitos testada apresenta heterogeneidade em resposta aos inseticidas, sendo a maior concentração utilizada para a CL50, a partir da análise de probit para o Temefós. Todos os inseticidas avaliados causaram mortalidade mais acentuada nas primeiras 24h exceto quando expostas à ivermectina. CONCLUSÕES: As larvas são suscetíveis a todos os inseticidas testados e há uma necessidade de um monitoramento dos inseticidas utilizados.

  17. The Colonization Dynamics of the Gut Microbiota in Tilapia Larvae

    OpenAIRE

    2014-01-01

    The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an environmental factor is very complicated. Interactions between factors are difficult to separate and any response could be masked due to high inter-individual variation even for individuals that sha...

  18. Effects of dietary vitamin C on fish and crustacean larvae

    OpenAIRE

    Merchie, G.; Lavens, P.; Sorgeloos, P.

    1995-01-01

    In order to assess the dietary needs for ascorbic acid (AA) at startfeeding, the AA content in the various live diets currently applied in aquaculture (algae, rotifers, Artemia ) was studied. Application of boosting techniques using ascorbyl palmitate (AP) as the vitamin C source enabled the transfer of elevated levels of bioactive vitamin C (up to 2500µg AA.g DW-1) via the live food chain into larvae of fish (Clarias gariepinus, Dicentrarchus labrax, Scophthalmus maximus), shrimp (Pennaeus v...

  19. Odour avoidance learning in the larva of Drosophila melanogaster

    Indian Academy of Sciences (India)

    Sukant Khurana; Mohammed Bin AbuBaker; Obaid Siddiqi

    2009-10-01

    Drosophila larvae can be trained to avoid odours associated with electric shock. We describe here, an improved method of aversive conditioning and a procedure for decomposing learning retention curve that enables us to do a quantitative analysis of memory phases, short term (STM), middle term (MTM) and long term (LTM) as a function of training cycles. The same method of analysis when applied to learning mutants dunce, amnesiac, rutabaga and radish reveals memory deficits characteristic of the mutant strains.

  20. Using black soldier fly larvae for processing organic leachates.

    Science.gov (United States)

    Popa, Radu; Green, Terrence R

    2012-04-01

    A large number of biodegradable byproducts including alcohols, soluble saccharides, volatile organic acids, and amines accumulate in the liquid fraction (leachate) produced as vegetal and food scrap waste decomposes. Untreated leachate, because it is rich in nutrients and organic byproducts, has a high chemical oxygen demand and is normally cleared of soluble organic byproducts by mineralization before its discharge into waterways. Mineralizing leachates using chemical and microbial biotechnologies is, however, a lengthy and costly process. We report here that the larvae of the black soldier fly Hermetia illucens (L.) (Diptera: Stratiomyidae), an insect rich in protein and lipids, and having significant commercial value, while feeding and growing off of compost leachate, lowers its chemical oxygen demand relative to that of leachate unexposed to larvae, neutralizes its acidity, and clears it of volatile organic acids, amines, and alcohols. These observations demonstrate that black soldier fly larvae could be used to help offset the cost and clean up of organic solutes in leachate waste streams while recycling carbon, nitrogen, and phosphate into usable and commercially valuable biomass. PMID:22606806

  1. Chlorpyrifos-induced toxicity in Duttaphrynus melanostictus (Schneider 1799) larvae.

    Science.gov (United States)

    Wijesinghe, M R; Bandara, M G D K; Ratnasooriya, W D; Lakraj, G P

    2011-05-01

    This study investigates the effects of continuous exposure to a widely used organophosphate pesticide, chlorpyrifos, on survival, growth, development, and activity of larvae of the Asian common toad, Duttaphrynus melanostictus Schneider 1799. Larvae were continuously exposed to six different concentrations (1-1,500 μg l(-1)) of commercial-grade chlorpyrifos for 14 days and monitored for 1 additional week. Chlorpyrifos at ≥1,000 μg l(-1) caused significantly high and dose-dependent mortality, and the weekly LC50(7 day-21 day) values ranged from 3,003 to 462 μg l(-1). Larvae surviving exposure to ≥500 μg l(-1) chlorpyrifos showed significant growth impairment, delays in metamorphosis, and decreased swimming activity. Tail abnormalities were the most common morphologic deformity at concentrations of 1,000 and 1,500 μg l(-1) chlorpyrifos. The findings of the present study highlight the need to recognize the potential risk that agrochemicals pose to amphibians inhabiting agricultural landscapes in Sri Lanka and other Asian countries. PMID:20669016

  2. Ecophysiology of dorsal versus ventral cuticle in flattened sawfly larvae

    Science.gov (United States)

    Boevé, Jean-Luc; Angeli, Sergio

    2010-06-01

    Platycampus larvae are highly cryptic leaf feeders characterised by a dorso-ventrally flattened body, the dorsal integument resembling a shield. Dorsal and ventral cuticles from Platycampus luridiventris were compared by histology and gel electrophoresis. By Azan-staining, a red and a blue layer were distinguished in the dorsal cuticle, while the ventral cuticle showed one, almost uniform blue layer, as in both cuticles of control species. The two cuticles from P. luridiventris had similar amounts and sodium dodecyl sulphate-polyacrylamide gel electrophoresis profiles of soluble proteins, but not insoluble proteins. One insoluble protein (MW ≈ 41 kDa) was visible as a large band in the ventral cuticle only. It is likely that this protein renders the cuticle elastic, and that the dorsal, red layer is the exocuticle, mainly composed of insoluble proteins. We discuss eco-physiological implications of the exocuticle in insects. Further, data from the literature indicate that the defence strategy in P. luridiventris larvae relies on being visually cryptic towards avian predators and tactically cryptic towards arthropod predators and parasitoids. Crypsis in both senses is favoured by the shield effect, itself based on an abnormally thick dorsal exocuticle. Although the larvae are external feeders, they may be considered as hidden from an ecological perspective.

  3. The larva of Drusus vinconi Sipahiler, 1992 (Trichoptera, Limnephilidae, Drusinae

    Directory of Open Access Journals (Sweden)

    Johann Waringer

    2013-07-01

    Full Text Available This paper describes the previously unknown larva of Drusus vinconi Sipahiler, 1992. Information on the morphology of the 5th larval instar is given, and the most important diagnostic features are illustrated. In the context of existing identification keys the larva of D. vinconi keys together with D. annulatus (Stephens, 1837, D. biguttatus (Pictet, 1834, D. ingridae Sipahiler, 1993, Hadimina torosensis Sipahiler, 2002 and Leptodrusus budtzi (Ulmer, 1913. These species differ in the contours of the pronotum in lateral view, the presence/absence of the pronotal transverse groove, the shape of the median notch of the pronotum (in anterior view, pronotal sculpturing, presence/absence of the lateral carina of the head capsule, the number of proximo-dorsal setae on the mid-and hind femora, where the lateral fringe starts on the abdomen, and in geographic distribution. With respect to zoogeography, Drusus vinconi is a (micro-endemic of the Western Pyrenees. The species prefers stony substratum in springs and springbrooks of the montane and subalpine region (Graf et al. 2008; Sipahiler 1992, 1993. As a grazer, the larvae of D. vinconi feed on biofilm and epilithic algae.

  4. Prevalence of American Foulbrood and Paenibacillus Larvae Genotypes in Bulgaria

    Directory of Open Access Journals (Sweden)

    Nikolina V. RUSENOVA

    2016-01-01

    Full Text Available This study aimed to analyse the prevalence of American foulbrood and Paenibacillus larvae genotypes in Bulgaria. For this purpose, data concerning American foulbrood outbreaks were used. Also, available data on the number of destroyed bee families covering a twenty-five-year period (1989 - 2013 was collected from the register of Bulgarian Food Safety Agency. In addition, Paenibacillus larvae genotypes in 15 apiaries were established by rep - PCR with BOXA1R and MBOREP1 primers. Results showed broad incidence of the disease, particularly at the beginning of the analysed period, with a tendency to reduction of affected apiaries and bee families at the end of the period. A statistically significant prevalence of American foulbrood in South Bulgaria compared to the northern regions was observed. Genotyping of Paenibacillus larvae revealed two genotypes: ab and AB, with the preponderance of the more virulent AB in South Bulgaria. The obtained results showed the need for conducting regular mandatory screening of bee colonies for early diagnostics of the disease and the implementation of relevant measures for American foulbrood prevention and control.

  5. Ingestion of Nanoplastics and Microplastics by Pacific Oyster Larvae.

    Science.gov (United States)

    Cole, Matthew; Galloway, Tamara S

    2015-12-15

    Plastic debris is a prolific contaminant effecting freshwater and marine ecosystems across the globe. Of growing environmental concern are "microplastics"and "nanoplastics" encompassing tiny particles of plastic derived from manufacturing and macroplastic fragmentation. Pelagic zooplankton are susceptible to consuming microplastics, however the threat posed to larvae of commercially important bivalves is currently unknown. We exposed Pacific oyster (Crassostrea gigas) larvae (3-24 d.p.f.) to polystyrene particles spanning 70 nm-20 μm in size, including plastics with differing surface properties, and tested the impact of microplastics on larval feeding and growth. The frequency and magnitude of plastic ingestion over 24 h varied by larval age and size of polystyrene particle (ANOVA, P plastic, with aminated particles ingested and retained more frequently (ANOVA, P plastic consumption and plastic load per organism was identified (Spearmans, r = 0.95, P plastic concentrations exceeding those observed in the marine environment resulted in no measurable effects on the development or feeding capacity of the larvae over the duration of the study. PMID:26580574

  6. Development and functional morphology of the mouthparts and foregut in larvae and post-larvae of Macrobrachium jelskii (Decapoda: Palaemonidae).

    Science.gov (United States)

    Rocha, Cristina Pantoja; Souza, Adelson Silva de; Maciel, Murilo; Maciel, Cristiana R; Abrunhosa, Fernando Araújo

    2016-05-01

    The morphology of the mouthparts and foregut of the larvae and post-larvae of Macrobrachium jelskii was investigated to determine their functional roles in feeding, in order to understand the larval feeding behaviour and the changes that occur during its development. The mouthparts and foregut of the zoea I and II are morphologically similar, rudimentary and non-functional in feeding. Only in the final larval stage, zoea III, do the external mouthparts and foregut become structurally more complex and thus likely to play a potential role in feeding. Two behavioral trials (point of no return, point of reserve saturation) evaluated the resistance to starvation in zoea I, II, and III. The results indicate that they have sufficient nutritional reserves to permit them to complete metamorphosis without feeding. Overall, our results suggest that the zoea I and II of Macrobrachium jelskii engage in obligate lecithotrophy and zoea III in facultative lecithotrophy. PMID:26899315

  7. Morphological and behavioral development of the piracanjuba larvae Desenvolvimento morfológico e comportamental de larvas de piracanjuba

    Directory of Open Access Journals (Sweden)

    Cláudia Maria Reis Raposo Maciel

    2010-05-01

    Full Text Available The objective of this work was to study the morphologic development and the swimming and feeding behaviors of piracanjuba larvae, Brycon orbignyanus Valenciennes (1849 (Characiformes, Characidae, Bryconinae, during the period from zero to 172 hours after hatching (standard length = 3.62 - 11.94 mm. The morphological analyses were accomplished by using a trinocular stereo microscope, while the behavioral analyses were performed through periodic observations. In 28 hours after hatching, the larvae (standard length = 6.25 ± 0.13 mm showed the following structural and behavioral characteristics that made them become active predators able to overcome a larval critical phase, the beginning of exogenous feeding: presence of pigmented eyes, terminal and wide mouth, developed oral dentition, developing digestive tube, yolk sac reduction, fins and swim bladder formation, horizontal swimming, cannibalism, and predation. Intense cannibalism among larvae was verified from 26 to 72 hours. At the end of the metamorphosis - 172 hours after hatching - the larvae measuring 11.94 + 0.80 mm in standard length presented a flexed notochord, caudal fin bifurcation, dorsal and anal fin formation, synchronized movements, and formation of shoals, characteristics that together allow enhanced perception and locomotio in exploration of the environment, determining the best moment for transfering to the fishponds. New studies can contribute to commercial fish farming by improving feeding management, performance, survival, and productivity of this species.Objetivou-se estudar o desenvolvimento morfológico e os comportamentos natatório e alimentar de larvas de piracanjuba, Brycon orbignyanus Valenciennes (1849 (Characiformes, Characidae, Bryconinae no período de 0 a 172 horas após a eclosão (comprimento-padrão = 3,62 - 11,94 mm. As análises morfológicas foram realizadas com auxílio de um microscópio estereoscópico trinocular e as comportamentais, por meio de

  8. Mananoligossacarídeo em dietas para larvas de tilápia Mannanoligosaccharides in diets for tilapia larvae

    Directory of Open Access Journals (Sweden)

    Kátia Kalko Schwarz

    2011-12-01

    Full Text Available Este experimento foi realizado para avaliar níveis crescentes de mananoligossacarídeo (MOS na dieta de larvas de tilápias-do-nilo (linhagem Supreme® na fase de reversão sexual durante 30 dias. Larvas de tilápia-do-nilo (n=1500, P=0,01 g ± 0,001 g foram distribuídas aleatoriamente em 30 tanques de 100 litros. Os peixes foram distribuídos em delineamento inteiramente casualizado, composto por seis tratamentos e cinco repetições. A dieta controle (isenta de MOS foi elaborada para conter aproximadamente 35% de proteína bruta e 3.100 kcal de ED/kg. As demais foram suplementadas com 0; 0,15; 0,30; 0,45; 0,60 e 0,75% de MOS em substituição ao milho da dieta controle. Com o aumento nos níveis de MOS nas dietas, foi observado aumento linear sobre o comprimento do intestino, a altura das vilosidades intestinais e a densidade dos vilos. Não houve diferença na composição corporal, no ganho em peso, no peso final, no comprimento final, no fator de condição, na taxa de sobrevivência e no número de células caliciformes do intestino das larvas. Os níveis de MOS tiveram efeito quadrático sobre a conversão alimentar, cujos melhores resultados foram obtidos com 0,34% de MOS. A utilização de MOS no nível de 0,34% em dietas para larvas de tilápia-do-nilo melhora a conversão alimentar e promove aumento do comprimento do intestino, da altura das vilosidades e da densidade de vilos intestinal.This experiment was conducted to evaluate increasing levels of mannanoligosaccharides (MOS in the diet of Nile tilapia larvae (Supreme® at the sex reversal stage for 30 days. Nile tilapia larvae (n = 1500, p = 0.01 ± 0.001 g, were randomly distributed in 30 tanks of 100 liters each, for 30 days. The fish were distributed in a randomized design with six treatments and five replicates. The control diet (no MOS was elaborated to contain approximately 35% of crude protein and 3,100 kcal DE/kg. Mannanoligosaccharides were included in the other diets

  9. Radiolabeling of infective third-stage larvae of Strongyloides stercoralis by feeding [75Se]selenomethionine-labeled Escherichia coli to first- and second-stage larvae

    International Nuclear Information System (INIS)

    A technique is described for radiolabeling Strongyloides stercoralis larvae with [75Se]selenomethionine. Cultures of an auxotrophic methionine-dependent stain of Escherichia coli were grown in a medium containing Dulbecco's modified Eagle's medium supplemented with 5% nutrient broth, amino acids, and [75Se]selenomethionine. When the 75Se-labeled bacterial populations were in the stationary phase of growth, cultures were harvested and the bacteria dispersed on agar plates to serve as food for S. stercoralis larvae. Use of nondividing bacteria is important for successful labeling because the isotope is not diluted by cell division and death of larvae attributable to overgrowth by bacteria is prevented. First-stage S. stercoralis larvae were recovered from feces of infected dogs and reared in humid air at 30 C on agar plates seeded with bacteria. After 7 days, infective third-stage larvae were harvested. The mean specific activity of 6 different batches of larvae ranged from 75 to 330 counts per min/larva with 91.8 +/- 9.5% of the population labeled sufficiently to produce an autoradiographic focus during a practicable, 6-wk period of exposure. Labeled infective larvae penetrated the skin of 10-day-old puppies and migrated to the small intestine, where the developed to adulthood

  10. Whole-body gene expression pattern registration in Platynereis larvae

    Directory of Open Access Journals (Sweden)

    Asadulina Albina

    2012-12-01

    Full Text Available Abstract Background Digital anatomical atlases are increasingly used in order to depict different gene expression patterns and neuronal morphologies within a standardized reference template. In evo-devo, a discipline in which the comparison of gene expression patterns is a widely used approach, such standardized anatomical atlases would allow a more rigorous assessment of the conservation of and changes in gene expression patterns during micro- and macroevolutionary time scales. Due to its small size and invariant early development, the annelid Platynereis dumerilii is particularly well suited for such studies. Recently a reference template with registered gene expression patterns has been generated for the anterior part (episphere of the Platynereis trochophore larva and used for the detailed study of neuronal development. Results Here we introduce and evaluate a method for whole-body gene expression pattern registration for Platynereis trochophore and nectochaete larvae based on whole-mount in situ hybridization, confocal microscopy, and image registration. We achieved high-resolution whole-body scanning using the mounting medium 2,2’-thiodiethanol (TDE, which allows the matching of the refractive index of the sample to that of glass and immersion oil thereby reducing spherical aberration and improving depth penetration. This approach allowed us to scan entire whole-mount larvae stained with nitroblue tetrazolium/5-bromo-4-chloro-3-indolyl phosphate (NBT/BCIP in situ hybridization and counterstained fluorescently with an acetylated-tubulin antibody and the nuclear stain 4’6-diamidino-2-phenylindole (DAPI. Due to the submicron isotropic voxel size whole-mount larvae could be scanned in any orientation. Based on the whole-body scans, we generated four different reference templates by the iterative registration and averaging of 40 individual image stacks using either the acetylated-tubulin or the nuclear-stain signal for each developmental

  11. Morphological and behavioral development of the piracanjuba larvae Desenvolvimento morfológico e comportamental de larvas de piracanjuba

    OpenAIRE

    Cláudia Maria Reis Raposo Maciel; Eduardo Arruda Teixeira Lanna; Alaor Maciel Junior; Juarez Lopes Donzele; Clóvis Andrade Neves; Eliane Menin

    2010-01-01

    The objective of this work was to study the morphologic development and the swimming and feeding behaviors of piracanjuba larvae, Brycon orbignyanus Valenciennes (1849) (Characiformes, Characidae, Bryconinae), during the period from zero to 172 hours after hatching (standard length = 3.62 - 11.94 mm). The morphological analyses were accomplished by using a trinocular stereo microscope, while the behavioral analyses were performed through periodic observations. In 28 hours after hatching, the ...

  12. Exposure to lead induces hypoxia-like responses in bullfrog larvae (Rana catesbeiana)

    Energy Technology Data Exchange (ETDEWEB)

    Rice, T.M.; Blackstone, B.J.; Nixdorf, W.L.; Taylor, D.H.

    1999-10-01

    Amphibians collected around mining sites, areas with extensive automobile traffic, and shooting ranges have been documented to contain high levels of lead. Lead-exposed amphibians might respond as if in hypoxic conditions because exposure is known to decrease hemoglobin levels, damage erythrocytes, and alter respiratory surfaces. Therefore, the authors exposed bullfrog larvae to either 0 or 780 {micro}g/L Pb and either 3.50 or 7.85 mg/L oxygen for 7 d and monitored activity, trips to the surface, and buccal ventilation rates. Activity was significantly decreased in larvae exposed to low oxygen, Pb, or both compared to activity of larvae in high oxygen with no Pb. Larvae exposed to both Pb and low oxygen displayed higher buccal ventilation rates than larvae exposed to either treatment separately. Lead-exposed larvae surfaced significantly more often than unexposed larvae even under high-oxygen conditions. Lead-exposed larvae decreased in mass during the exposure period, whereas unexposed larvae increased in mass. Lead exposure could decrease survival of larvae in the field not only because of physiological problems due to decreased oxygen uptake but also because of greater predation pressure due to increased presence at the surface and reduced growth rates.

  13. Production of the catechol type siderophore bacillibactin by the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Hertlein, Gillian; Müller, Sebastian; Garcia-Gonzalez, Eva; Poppinga, Lena; Süssmuth, Roderich D; Genersch, Elke

    2014-01-01

    The Gram-positive bacterium Paenibacillus larvae is the etiological agent of American Foulbrood. This bacterial infection of honey bee brood is a notifiable epizootic posing a serious threat to global honey bee health because not only individual larvae but also entire colonies succumb to the disease. In the recent past considerable progress has been made in elucidating molecular aspects of host pathogen interactions during pathogenesis of P. larvae infections. Especially the sequencing and annotation of the complete genome of P. larvae was a major step forward and revealed the existence of several giant gene clusters coding for non-ribosomal peptide synthetases which might act as putative virulence factors. We here present the detailed analysis of one of these clusters which we demonstrated to be responsible for the biosynthesis of bacillibactin, a P. larvae siderophore. We first established culture conditions allowing the growth of P. larvae under iron-limited conditions and triggering siderophore production by P. larvae. Using a gene disruption strategy we linked siderophore production to the expression of an uninterrupted bacillibactin gene cluster. In silico analysis predicted the structure of a trimeric trithreonyl lactone (DHB-Gly-Thr)3 similar to the structure of bacillibactin produced by several Bacillus species. Mass spectrometric analysis unambiguously confirmed that the siderophore produced by P. larvae is identical to bacillibactin. Exposure bioassays demonstrated that P. larvae bacillibactin is not required for full virulence of P. larvae in laboratory exposure bioassays. This observation is consistent with results obtained for bacillibactin in other pathogenic bacteria. PMID:25237888

  14. Laboratory investigation of daily food intake and gut evacuation in larvae of African catfish Clarias gariepinus under different feeding conditions

    OpenAIRE

    García-Ortega, A.; Verreth, J.A.J.; Vermis, K.; Nelis, H J; Sorgeloos, P.; Verstegen, M.W.A.

    2010-01-01

    Abstract Temporary accumulation of ascorbic acid 2-sulfate (AAS) was measured to estimate food intake and gut evacuation in larvae of African catfish. Fish larvae were fed decapsulated cysts of Artemia containing AAS. In a first experiment it was found that no biosynthesis of AAS occurs in the larvae of this species. In a second experiment, the gut contents of the fish larvae fed were calculated as they changed during development. In a third experiment, the gut evacuation rate of fish larvae ...

  15. Viral encephalitis of tilapia larvae: primary characterization of a novel herpes-like virus.

    Science.gov (United States)

    Shlapobersky, Mark; Sinyakov, Michael S; Katzenellenbogen, Mark; Sarid, Ronit; Don, Jeremy; Avtalion, Ramy R

    2010-04-10

    We report here an outbreak of an acute disease that caused high mortality rate in laboratory-reared tilapia larvae. The disease was initially observed in inbred gynogenetic line of blue tilapia larvae (Oreochromis aureus) and could be transmitted to larvae of other tilapia species. Based on the clinical manifestation (a whirling syndrome), we refer to the disease as viral encephalitis of tilapia larvae. The disease-associated DNA virus is described and accordingly designated tilapia larvae encephalitis virus (TLEV). A primary morphological, biophysical and molecular characterization of TLEV is presented. By virtue of these properties, the newly discovered virus is a herpes-like virus. Phylogenetic analysis, albeit limited, confirms this assumption and places TLEV within the family of Herpesviridae and distantly from the families Alloherpesviridae and Iridoviridae. By using PCR with virus-specific primers, diseased larvae and adult TLEV carriers were also identified in tilapia delivered from external hatcheries. PMID:20117816

  16. A behavioral method for separation of house fly (Diptera: Muscidae) larvae from processed pig manure.

    Science.gov (United States)

    Cicková, Helena; Kozánek, Milan; Morávek, Ivan; Takác, Peter

    2012-02-01

    A behavioral method applicable in biodegradation facilities for separation of house fly (Musca domestica L.) larvae from processed pig manure is presented. The method is based on placing a cover over the larval rearing tray, while escaping larvae are collected in collection trays. Separation units must be placed in a dark room to avoid negative phototactic responses of the larvae. After 24 h of separation, over 70% of the larvae escaped from processed manure and were collected in collection trays. Most of the larvae pupated within 48 h after separation. Mean weight of pupae recovered from manure residue was not significantly different from mean weight of pupae of separated individuals. Eclosion rate of pupae recovered from manure residue was significantly lower than eclosion of separated individuals, and was strongly related to separation success. Factors responsible for escape behavior of larvae are discussed. PMID:22420256

  17. Effect of electronic beam irradiation on last instar larvae of lasioderma serricorne fabricius

    International Nuclear Information System (INIS)

    The electronic beam irradiation effects on the last instar larvae of cigarette beetle (Lasioderma serricorne Fabricius) in tobacco were studied, and the mortality in 42 days, lethal time, pupation rate, emergence rate and reproductive capacity after irradiation were measured. The results showed that the mortality increased with the increase of irradiation dosage, but the larvae did not dead immediately. The last instar larvae irradiated by the dosages higher than 480 Gy could prevent the development of larvae to adults. No new generation was found after 300 Gy treatment of the last instar larvae. So 300 Gy irradiation could be considered as a suitable dose to prevent the reproduction of cigarette beetle of the last instar larvae in the tobacco. (authors)

  18. Drosophila melanogaster larvae control amylase secretion according to the hardness of food

    OpenAIRE

    Sakaguchi, Honami; Suzuki, Masataka G.

    2013-01-01

    Drosophila melanogaster larvae excrete amylase and perform external digestion of their food. In this study, to investigate whether their external digestion ability varies in response to changes in the external environment, we measured the relative amount of amylase excreted by larvae using a new method: the iodine starch agar method (ISAM). Analysis using this method revealed that the amount of amylase excreted by larvae increased in accordance with the increase in the agar concentration. In ...

  19. Kaolin as a possible treatment against lepidopteran larvae and mites in organic fruit production

    OpenAIRE

    Jaastad, G.; Røen, D.; Hovland, B.; Opedal, O.

    2006-01-01

    Few control methods are available in Norwegian organic fruit production that can prevent damage by early and late larvae. Also phytophagous mites are difficult to control without harming the beneficial mites. Proc-essed kaolin function by coating trees and thus creating a physical barrier to infestation, impeding move-ment, feeding and egg-laying. Kaolin may reduce feeding and movement of over-wintering tortricide larvae and other larvae that hatch early in spring and have a repellent effect ...

  20. Bothid larvae (Pleuronectiformes - Pisces) of the Gulf of Thailand and South China Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    of collection. All other species exhibited different degree of preference to day or night in different regions. This may be due to the ecological factors prevailing in such regions which may have influence in their growth and distribution. BOTHID LARVAE - GULF... water movements but not with strong currents. The effect and pattern of the prevailing current is one of the important factors that decides the distribution of the larvae. The abundance of bothid larvae in the Gulf of Thailand compared to the South...

  1. Rearing of catfish (Clarias batrachus Lin.) larvae with live and prepared feeds

    OpenAIRE

    Yasmin, A.; Mollah, M.F.A; Haylor, G.S.

    1998-01-01

    Provision or live feed (Tubificid worms) attributed significantly better weight gain in the five days old Clarias batrachus larvae when reared for another 28 days compared to those fed mixed feed (live and artificial) and artificial feed only. Larvae fed mixed feed showed significantly better weight gain compared to those fed only artificial feed and the survival rate was similar to those fed only live feed. Both the weight gain and survival rate were the lowest for the larvae reared only on ...

  2. Survival, Growth and Reproduction of Cryopreserved Larvae from a Marine Invertebrate, the Pacific Oyster (Crassostrea gigas)

    OpenAIRE

    Suquet, Marc; Labbé, Catherine; Puyo, Sophie; Mingant, Christian; Quittet, Benjamin; Boulais, Myrina; Queau, Isabelle; Ratiskol, Dominique; Diss, Blandine; Haffray, Pierrick

    2014-01-01

    This study is the first demonstration of successful post-thawing development to reproduction stage of diploid cryopreserved larvae in an aquatic invertebrate. Survival, growth and reproductive performances were studied in juvenile and adult Pacific oysters grown from cryopreserved embryos. Cryopreservation was performed at three early stages: trochophore (13 +/- 2 hours post fertilization: hpf), early D-larvae (24 +/- 2 hpf) and late D-larvae (43 +/- 2 hpf). From the beginning (88 days) at th...

  3. Effect og bioactive products on innate immunity and development of Atlantic halibut (Hippoglossus hippoglossus L.) larvae

    OpenAIRE

    Rut Hermannsdóttir

    2008-01-01

    Halibut larvae were treated with various bioactive products and the effects on selected components of the innate immune system investigated. Effects on growth, survival and normal development of larvae were also studied. The bioactive products which were tested were chitosan and protein hydrolysates from cod, blue whiting and pollock. The larvae where treated with bioactive products from the onset of feeding or from 4-5 weeks after the onset of feeding and throughout the first feeding period....

  4. Screening alternative antibiotics against oxytetracycline-susceptible and -resistant Paenibacillus larvae

    OpenAIRE

    Kochansky, Jan; Knox, David; Feldlaufer, Mark; Pettis, Jeffery

    2001-01-01

    International audience Since resistance of the causative organism of American foulbrood, Paenibacillus larvae subsp. larvae, to oxytetracycline (OTC) is becoming widespread in the United States, we began a search for effective alternative antibiotics. We investigated the sensitivity of P. l. larvae to 27 antibiotics, which were primarily ones already registered with the US Food and Drug Administration for agricultural uses. Bacterial resistance to OTC also conferred resistance to other tet...

  5. KERENTANAN LARVA AEDES AEGYPTI TERHADAP TEMEFOS DI TIGA KELURAHAN ENDEMIS DEMAM BERDARAH DENGUE KOTA SUKABUMI

    OpenAIRE

    Hubullah Fuadzy; Dewi Nur Hodijah; Asep Jajang; Mutiara Widawati

    2015-01-01

    AbstractResistance of Aedes aegypti larvae against temephos influeneed the efforts of Dengue Fever vector control . The purpose of this study was to determine the status of susceptibility of Ae. aegypti larvae against temephos in three Dengue Fever endemic areas in Sukabumi. Design laboratory experiment with random design. approach group. Sample of Ae. aegypti larvae instar 3 and 4 had been taken from Subdistrict Baros, Sriwedari, Nangeleng. Susceptibility test, in performed according to Worl...

  6. On the edge: pharmacological evidence for anxiety-related behavior in zebrafish larvae

    OpenAIRE

    Richendrfer, H.; Pelkowski, S.D.; Colwill, R.M.; Creton, R.

    2011-01-01

    Zebrafish larvae are ideally suited for high-throughput analyses of vertebrate behavior. The larvae can be examined in multiwell plates and display a range of behaviors during early development. Previous studies have shown that zebrafish larvae display a preference for the edge of the well and several lines of evidence suggest this edge preference (thigmotaxis) may be a measure of anxiety. In the present study, we further examined the relation between edge preference and anxiety by imaging ze...

  7. Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

    OpenAIRE

    Sacchi L.; Corona S.; Gajadhar A.A.; Pozio E.

    2001-01-01

    The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear), T. spiralis (horses and humans), T. pseudospiralis (a laboratory mouse) and T. papuae (a laboratory mouse) were examined. Analysi...

  8. Dynamic of decapod crustacean larvae on the entrance of Guanabara bay

    OpenAIRE

    Fernandes Lohengrin Dias de Almeida; Bonecker Sérgio Luiz Costa; Valentin Jean Louis

    2002-01-01

    In the present study, we observed seasonal variations in the density of decapod larvae as well as changes in density related to diurnal and tidal cycles. Among the decapod larvae collected, portunids and grapsids were the most abundant, especially during nocturnal ebb tides and near the surface. The same results were obtained in late winter (September) and late summer (March). These results demonstrated a flow of decapod larvae from Guanabara Bay to adjacent coastal waters. Luciferid (Lucifer...

  9. Humidity Detection and Hygropreference Behavior in Larvae of the Tobacco hornworm, Manduca sexta

    OpenAIRE

    Rowley, Marc; Hanson, Frank

    2007-01-01

    Water is a critical resource for any terrestrial animal, especially for a soft-bodied insect such as larvae of the tobacco hornworm, Manduca sexta L. (Lepidoptera: Sphingidae). Strategies for coping with a dry environment might include seeking out regions of high relative humidity that reduce desiccative stress, or to find and imbibe liquid water. Desiccated larvae placed in a linear arena with a humidity gradient preferred the humid end, whereas un-desiccated larvae did not. This behavior wa...

  10. Jenis – Jenis Larva Nyamuk di Kelurahan Baru–Ladang Bambu, Kecamatan Medan Tuntungan

    OpenAIRE

    Gunasegaran, Logeswaran

    2013-01-01

    Mosquitoes are the cause of some dangerous disease to humans. Larvae is an important stage in mosquitoes life cycle and it is important to identify its presence and stop its development. This study aims to identify the type of mosquito larvaes which are found in Kelurahan Baru – Ladang Bambu, Kecamatan Medan Tuntungan . Sample mosquito larvaes collected in Kelurahan Baru – Ladang Bambu, Kecamatan Medan Tuntungan and examined under microscope to identify the species with the help of identifica...

  11. Gastrointestinal symptoms resembling ulcerative proctitis caused by larvae of the drone fly Eristalis tenax.

    Science.gov (United States)

    Desoubeaux, Guillaume; Gaillard, Julien; Borée-Moreau, Diane; Bailly, Éric; Andres, Christian R; Chandenier, Jacques

    2014-04-01

    We report a case of facultative intestinal myiasis due to larvae of the drone fly Eristalis tenax, also named the rat-tailed maggots. The development of larvae in the lower bowel was responsible for non-specific gastrointestinal symptoms that resembled ulcerative proctitis. The diagnosis was established upon the observation of four spontaneously excreted mobile larvae. The definite identification of the E. tenax species was made possible by scanning electron microscopy. The clinical outcome was satisfactory. PMID:24766340

  12. Differences in vertical and horizontal distribution of fish larvae and zooplankton, related to hydrography

    OpenAIRE

    Höffle, Hannes; Nash, Richard D. M.; Falkenhaug, Tone; Munk, Peter

    2013-01-01

    Planktonic fish larvae have little influence on their horizontal distribution, while they are able to control their vertical position in the water column. While prey and light are among the factors with an apparent influence on the vertical distribution, the effects of other factors are less clear. Notably, distributional differences between larvae of different fish species are poorly understood. Information on the horizontal distribution of larvae of 27 species and the vertical distribution ...

  13. Descrição da larva de Erythemis mithroides (Brauer e notas sobre outras larvas conhecidas do gênero (Odonata, Libellulidae Description of the larva of Erythemis mithroides (Brauer and notes on other known larvae of the genus (Odonata, Libellulidae

    Directory of Open Access Journals (Sweden)

    J.M. Costa

    1993-01-01

    Full Text Available The last instar larva of Erythemis mithroides (Brauer, 1900 is described and figured based on exuviae of reared specimens. A comparative analysis of this immature stage and the known larvae of the genus are furnished according to the data available in the literature and of specimens of E credula (Hagen, 1861 and E. vesiculosa (Fab., 1775 permiting a diagnose for the larvae of the genus Erylhemis Hagen, 1861.

  14. Thyroid endocrine disruption of acetochlor on zebrafish (Danio rerio) larvae.

    Science.gov (United States)

    Yang, Mei; Hu, Jingjin; Li, Shuying; Ma, Youning; Gui, Wenjun; Zhu, Guonian

    2016-06-01

    The herbicide acetochlor is widely used and detected in the environment and biota, and has been suspected to disrupt the thyroid endocrine system, but underlying mechanisms have not yet been clarified. In the present study, zebrafish larvae (7 days post-fertilization) were exposed to a series concentration of acetochlor (0, 1, 3, 10, 30, 100 and 300 µg l(-1) ) within a 14-day window until 21 days post-fertilization. Thyroid hormones and mRNA expression profiles of genes involved in the hypothalamic-pituitary-thyroid (HPT) axis were analyzed. Exposure to the positive control, 3,5,3'-triiodothyronine (T3 ), altered the mRNA expression, suggesting that the HPT axis in the critical window of zebrafish responded to chemical exposure and could be used to evaluate the effects of chemicals on the thyroid endocrine system. The mRNA expressions of genes involved in thyroid hormone synthesis (tshβ, slc5a5 and tpo) were upregulated significantly with acetochlor treatment, which might be responsible for the increased thyroxine concentrations. The downregulation of genes related to thyroid hormone metabolism (dio1 and ugt1ab) and transport (ttr) in zebrafish larvae exposed to acetochlor might further explain the increased thyroxine levels and decreased T3 levels. The mRNA expression of the thyroid hormone receptor (trα) was also upregulated upon acetochlor exposure. Results suggested that acetochlor altered mRNA expression of the HPT axis-related genes and changed the whole body thyroid hormone levels in zebrafish larvae. It demonstrated that acetochlor could cause endocrine disruption of the thyroid system by simulating the biological activity of T3 . Copyright © 2015 John Wiley & Sons, Ltd. PMID:26397822

  15. Volatiles induced by the larvae of the Asian corn borer (Ostrinia furnacalis) in maize plants affect behavior of conspecific larvae and female adults

    Institute of Scientific and Technical Information of China (English)

    Cui-Hong Huang; Feng-Ming Yan; John A.Byers; Rong-Jiang Wang; Chong-Ren Xu

    2009-01-01

    Effects of maize (Zea mays L.) volatiles induced by larvae of the Asian corn borer, Ostrinia furnacalis (Guenee), on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae-induced maize volatiles; female responded to (E)-2-hexenal, nonanal, (Z)-3-hexen-1-ol and three unknown compounds while the male only responded to (E)-2-hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer-damaged plants as well as to synthetic famesene, but were repelled by (Z)-3-hexen- 1-ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with (E)-2-hexenal or (Z)-3-hexen-l-ol than on wax paper treated with hexane (control). The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.

  16. Catching large herring larvae: Gear applicability and larval distribution

    DEFF Research Database (Denmark)

    Munk, Peter

    1988-01-01

    given to the influence of gear speed on catching effectiveness. An additional objective was to investigate larval distributional patterns of potential importance to sampling strategy. Gear speed had a pronounced influence on the efficiency of the IKMT. Catches per unit volume filtered decreased to one...... third when speed was increased by one knot. The efficiency of the MIK did not change in the speed range investigated, and this gear was in every case more efficient than the IKMT. Larvae were found to be patchily distributed at the scale of sampling, and the degree of patchiness did not increase when...

  17. Immunization with irradiated larvae against Dictyocaulus filaria in young lambs

    Energy Technology Data Exchange (ETDEWEB)

    Dhar, D.N.; Sharma, R.L.

    1981-12-01

    In the lungworm-endemic areas of Kashmir, 6-10 week old lambs of Karnah and Kashmir Merino breeds were vaccinated with two doses of 50 kR gamma-irradiated larvae of Dictyocaulus filaria, given a month apart. Assessed on the basis of reduced prevalence and significantly lower faecal larval output over an eight-month observation period, vaccinated lambs showed a high degree of resistance to naturally acquired D. filaria infection. The results also show that vaccination against D. filaria provided some degree of protection against infection with other lungworm species.

  18. Immunization with irradiated larvae against Dictyocaulus filaria in young lambs

    International Nuclear Information System (INIS)

    In the lungworm-endemic areas of Kashmir, 6-10 week old lambs of Karnah and Kashmir Merino breeds were vaccinated with two doses of 50 kR gamma-irradiated larvae of Dictyocaulus filaria, given a month apart. Assessed on the basis of reduced prevalence and significantly lower faecal larval output over an eight-month observation period, vaccinated lambs showed a high degree of resistance to naturally acquired D. filaria infection. The results also show that vaccination against D. filaria provided some degree of protection against infection with other lungworm species. (Auth.)

  19. A linear model for the dynamics of fish larvae

    Directory of Open Access Journals (Sweden)

    Noureddine Ghouali

    2004-11-01

    Full Text Available We consider a linear model for the growth and the dispersion of fish larvae of certain species. Dispersion is modeled as entailed by the combination of transport and vertical diffusion. We generalize the work of Boushaba, Arino and Boussouar [5,6] in the sense that horizontal velocities are uniform throughout the water column; but we deal with vertical component velocity and vertical diffusion depending on the space variables and on time, which was not the case in [5,6]. This new vision leads us to non-autonomous problems, the aim of this work is to show the existence, uniqueness, and positivity of solutions.

  20. Feeding rates of the jellyfish Aurelia aurita on fish larvae

    DEFF Research Database (Denmark)

    Titelman, J.; Hansson, L.J.

    2006-01-01

    prey captured by A. aurita during 2.5 h of feeding at extremely high prey concentration (> 200 prey l(-1)). Clearance rate in darkness scaled with jellyfish diameter to a power of similar to 1.7 for jellyfish 3.9-9.5 cm in diameter. The jellyfish did not alter their umbrella pulse frequency in response...... to presence of fish larvae. There were no significant differences between A. aurita feeding rates in light and darkness for yolk sac prey ages 0-7 days (at 7.5 degrees C). Although prey vision and escape abilities of fish may develop rapidly during early larval ontogeny, these factors apparently have...

  1. Drosophila melanogaster larvae make nutritional choices that minimize developmental time.

    Science.gov (United States)

    Rodrigues, Marisa A; Martins, Nelson E; Balancé, Lara F; Broom, Lara N; Dias, António J S; Fernandes, Ana Sofia D; Rodrigues, Fábio; Sucena, Élio; Mirth, Christen K

    2015-10-01

    Organisms from slime moulds to humans carefully regulate their macronutrient intake to optimize a wide range of life history characters including survival, stress resistance, and reproductive success. However, life history characters often differ in their response to nutrition, forcing organisms to make foraging decisions while balancing the trade-offs between these effects. To date, we have a limited understanding of how the nutritional environment shapes the relationship between life history characters and foraging decisions. To gain insight into the problem, we used a geometric framework for nutrition to assess how the protein and carbohydrate content of the larval diet affected key life history traits in the fruit fly, Drosophila melanogaster. In no-choice assays, survival from egg to pupae, female and male body size, and ovariole number - a proxy for female fecundity - were maximized at the highest protein to carbohydrate (P:C) ratio (1.5:1). In contrast, development time was minimized at intermediate P:C ratios, around 1:2. Next, we subjected larvae to two-choice tests to determine how they regulated their protein and carbohydrate intake in relation to these life history traits. Our results show that larvae targeted their consumption to P:C ratios that minimized development time. Finally, we examined whether adult females also chose to lay their eggs in the P:C ratios that minimized developmental time. Using a three-choice assay, we found that adult females preferentially laid their eggs in food P:C ratios that were suboptimal for all larval life history traits. Our results demonstrate that D. melanogaster larvae make foraging decisions that trade-off developmental time with body size, ovariole number, and survival. In addition, adult females make oviposition decisions that do not appear to benefit the larvae. We propose that these decisions may reflect the living nature of the larval nutritional environment in rotting fruit. These studies illustrate the

  2. The use of morphological and histological features as nutritional condition indices of Pagrus pagrus larvae

    Directory of Open Access Journals (Sweden)

    Marina Vera Diaz

    2013-09-01

    Full Text Available Morphometrical and histological techniques were employed to characterize Pagrus pagrus larvae nutritional condition. Larvae were reared in laboratory under controlled conditions with the main objective of testing whether these methodologies allowed finding differences between larvae from different feeding treatments. Once yolk was consumed (three days after hatching larvae were assigned to a feeding treatment: starved during the whole experiment; delayed feeding, starved during three days; fed during the entire experiment. Algae (Nannochloropsis oculata and rotifers (Brachionus plicatilis were provided to larvae for feed treatments. Larvae were fixed daily; for morphometrical purposes in 5% formaldehyde solution, and in Bouin for histological sections. Results herein obtained showed that both methodologies are sensitive enough to distinguish larvae characterized by different nutritional condition states obtained from the feeding treatments. Consequently, these methodologies could be employed in wild red porgy larvae in order to asses their nutritional condition. These techniques could also be employed to check larval quality obtained with aquaculture purposes to estimate the effects of changes in rearing protocols or kind of food supply and thus, to guaranty a higher survival of early developmental stages of reared larvae.

  3. The Effects of Shrimp Gut Probiotic Bacteria on the Shrimp Larvae (Penaeus Chinensis)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The survival rates of shrimp larvae in different stage are higher than those of control groups when probiotic bacteria strains X4B-1 and X1B-1 which are isolated from gut of adult shrimp are added into the little volume rearing sea water of shrimp larvae. The effects of probiotic bacteria are evaluated by challenge test (pathogenic bacteria Z3G2 isolated from disease shrimp larvae in the hatchery of Jimo town) and low salinity stress resistance tests on shrimp larvae, the survival rate and lengths of the shrimp larvae in the experiment are determined. Results indicate that 1. The survival rate, ability of resistant to low salinity, lengths of the delivered shrimp larvae are improved after the strains of probiotic bacteria, X4B-1 or X1B-1, are added into the rearing sea water of hatchery. 2. The addition of the probiotic bacteria could not influence the change of the bacteria number, NH3-N and COD value in the rearing sea water. 3. The probiotic bacteria used in the experiment have many enzymes such as Lipase, Amylase, Gelatinase and Lecithinase. These enzymes may help the probiotic bacteria to digest the food components fed to shrimp larvae and increase the digestive efficiency of post larvae. This may be one of the reasons why these probiotic bacteria are beneficial to the shrimp larvae.

  4. House fly oviposition inhibition by larvae ofHermetia illucens, the black soldier fly.

    Science.gov (United States)

    Bradley, S W; Sheppard, D C

    1984-06-01

    Wild populations of house flies were inhibited from ovipositing into poultry manure containing larvae of the black soldier fly,Hermetia illucens (L.). A laboratory strain of house fly responded differently, readily ovipositing into manure with lower densities of soldier fly larvae, but avoiding the higher densities tested. The amount of timeH. illucens larvae occupy the manure prior to an oviposition test influences ovipositional responses of house flies. Manure conditioned byH. illucens larvae for 4-5 days did not significantly inhibit house fly oviposition. We suggest that some type of interspecific chemical communication (allomone) is present. PMID:24318779

  5. Cutaneous larva migrans in northern climates. A souvenir of your dream vacation

    Energy Technology Data Exchange (ETDEWEB)

    Edelglass, J.W.; Douglass, M.C.; Stiefler, R.; Tessler, M.

    1982-09-01

    Three young women recently returned to the metropolitan Detroit area with cutaneous larva migrans. All three had vacationed at a popular club resort on the Caribbean island of Martinique. Cutaneous larva migrans is frequently seen in the southern United States, Central and South America, and other subtropical areas but rarely in northern climates. Several organisms can cause cutaneous larva migrans, or creeping eruption. The larvae of the nematode Ancylostoma braziliense are most often the causative organisms. Travel habits of Americans make it necessary for practitioners in northern climates to be familiar with diseases contracted primarily in warmer locations. The life cycle of causative organisms and current therapy are reviewed.

  6. Secreted and immunogenic proteins produced by the honeybee bacterial pathogen, Paenibacillus larvae.

    Science.gov (United States)

    Antúnez, Karina; Anido, Matilde; Evans, Jay D; Zunino, Pablo

    2010-03-24

    American Foulbrood is a severe disease affecting larvae of honeybee Apis mellifera, causing significant decrease in the honeybee population, beekeeping industries and agricultural production. In spite of its importance, little is known about the virulence factors secreted by Paenibacillus larvae during larval infection. The aim of the present work was to perform a first approach to the identification and characterization of P. larvae secretome. P. larvae secreted proteins were analyzed by SDS-PAGE and identified by MALDI-TOF. Protein toxicity was evaluated using an experimental model based on feeding of A. mellifera larvae and immunogenicity was evaluated by Western blot, using an antiserum raised against cells and spores of P. larvae. Ten different proteins were identified among P. larvae secreted proteins, including proteins involved in transcription, metabolism, translation, cell envelope, transport, protein folding, degradation of polysaccharides and motility. Although most of these proteins are cytosolic, many of them have been previously detected in the extracellular medium of different Bacillus spp. cultures and have been related to virulence. The secreted proteins resulted highly toxic and immunogenic when larvae were exposed using an experimental model. This is the first description of proteins secreted by the honeybee pathogen P. larvae. This information may be relevant for the elucidation of bacterial pathogenesis mechanisms. PMID:19781868

  7. Description of the third instar larvae of five species of Cyclocephala (Coleoptera, Melolonthidae, Dynastinae from Mexico

    Directory of Open Access Journals (Sweden)

    Miguel A. Morón

    2014-09-01

    Full Text Available Description of the third instar larvae of five species of Cyclocephala (Coleoptera, Melolonthidae, Dynastinae from Mexico. Larvae of four species of Cyclocephala are described for the first time based on specimens collected in Mexican localities: C. barrerai Martínez, 1969 from Puebla, C. sinaloae Howden & Endrödi, 1966 from Sinaloa, C. fasciolata Bates, 1888 from Veracruz, and C. jalapensis Casey, 1915 from Hidalgo. Larva of C. lunulata Burmeister, 1847, is redescribed based on specimens from the Mexican states of Morelos, Puebla, and Veracruz. Diagnostic structures are illustrated and the differences and similarities of each species with other previously described larvae of the genus are commented.

  8. Paenilarvins: Iturin family lipopeptides from the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Sood, Sakshi; Steinmetz, Heinrich; Beims, Hannes; Mohr, Kathrin I; Stadler, Marc; Djukic, Marvin; von der Ohe, Werner; Steinert, Michael; Daniel, Rolf; Müller, Rolf

    2014-09-01

    The bacterium Paenibacillus larvae has been extensively studied as it is an appalling honey bee pathogen. In the present work, we screened crude extracts derived from fermentations of P. larvae genotypes ERIC I and II for antimicrobial activity, following the detection of four putative secondary metabolite gene clusters that show high sequence homology to known biosynthetic gene clusters for the biosynthesis of antibiotics. Low molecular weight metabolites produced by P. larvae have recently been shown to have toxic effects on honey bee larvae. Moreover, a novel tripeptide, sevadicin, was recently characterized from laboratory cultures of P. larvae. In this study, paenilarvins, which are iturinic lipopeptides exhibiting strong antifungal activities, were obtained by bioassay-guided fractionation from cultures of P. larvae, genotype ERIC II. Their molecular structures were determined by extensive 2D NMR spectroscopy, high resolution mass spectrometry, and other methods. Paenilarvins are the first antifungal secondary metabolites to be identified from P. larvae. In preliminary experiments, these lipopeptides also affected honey bee larvae and might thus play a role in P. larvae survival and pathogenesis. However, further studies are needed to investigate their function. PMID:25069424

  9. Electrophoretic protein pattern of the flesh fly, Sarcophaga bullata larvae untreated and treated with gamma radiation

    International Nuclear Information System (INIS)

    The objective of this study was to determine the variation induced in electrophoretic protein pattern of the flesh fly, Sarcophaga bullata (first and third instar larvae) irradiated with 30, 45, 60 and 75 Gy comparing with unirradiated larvae. SDS- polyacrylamide gel electrophoresis (SDS- PAGE) showed a variable number of 14 electrophoretic protein bands in the whole body tissue of first instar larvae with molecular weight ranged between 80.439 to 10.542 kDa .In control (unirradiated larvae) the number of detected bands was 12 bands, while in larvae irradiated with 30 and 45 Gy the number of detected bands was 13 bands. Two new bands were detected and one band was disappeared as compared with control. Irradiation of larvae with 60 and 75 Gy led to the appearance of 12 bands; a new band was appeared and another one was disappeared as compared with control. So, there were 11 monomorphic bands, two poly morphic bands and one unique band. The electrophoretic protein bands of the whole body tissue of the third instar larvae showed also a variable No. of 14 bands with molecular weight ranged between 79.932 to 12.077 kDa. In control (unirradiated larvae) the number of detected bands was 13 bands. In larvae irradiated with 30,45 and 60 Gy the number of bands was 14 bands, one new band was detected in larvae irradiated with 30, 45, 60 and 75 Gy and one band disappeared in larvae irradiated with 75 Gy. Also, the number of detected bands was 13 bands comparing with control. So, there are 12 monomorphic band and two polymorphic band comparing with the polymorphism of protein bands in first and third instar larvae of Sbullata it was noticed that in first instar larvae, there were 11 monomorphic bands compared to 12 bands in third instar larvae. One unique band was appeared in first instar larvae and disappeared in third ones. The percentage of polymorphism was 21.429% and 14.286% in the 1st and 3rd instar larvae, respectively. The quantitative analysis also clearly indicated

  10. Uptake and metabolism of dissolved amino acids by larvae and embryos of three gastropod species

    International Nuclear Information System (INIS)

    Dissolved organic matter is a potential nutritional resource for soft-bodied marine invertebrates. Experiments were done with developmental stages of three gastropod species to examine uptake kinetics and metabolism of dissolved amino acids. Free-swimming larvae of Crepidula fornicata and Thais-haemastoma were fed before experiments or starved for 48 hours before experiments to see whether nutritional state affected uptake of 14C-glycine of 14C-alanine. Time course of amino acid uptake was linear from 0-100 minutes for fed and starved larvae of both species. Uptake rates of starved T. haemastoma larvae were similar to or greater than rates for fed larvae, while uptake rates of starved C. fornicata larvae are similar to or less than rates for fed larvae. Starvation may enhance uptake by T. haemastoma larvae. 14CO2 was detected 10 minutes after larval exposure to labeled amino acids began, indicating rapid catabolism of amino acids. Label was found in protein extracted from larvae, indicating that absorbed glycine and alanine can be used for protein synthesis. A greater percent of glycine and alanine was converted to CO2 by starved larvae of both species. Encapsulated embryos of Nucella lapillus were used to study uptake and metabolism of amino acids because encapsulated embryos are in a bacteria-free environment. Uptake by embryos was linear from 10-90 minutes. Because capsules were bacteria-free embryos were the agents responsible for uptake and metabolism of labeled amino acids

  11. BIOLOGICAL AND MORPHOLOGICAL EFFECTS OF CHITINSYNTHESIS INHIBITOR (TRIFLUMURON) ON ANOPHELINE LARVAE

    OpenAIRE

    E. Farashiani; H. Ladonni

    1999-01-01

    Triflumuron (Bay sir 8514) is one of many benzoylated ureas, which inhibit chitin synthesis during insect molting and are commonly referred to as insect growth regulators or I. G. Rs. The post emergence efficacy of triflumuron (SC 48%) was evaluated against larvae of Anopheles stephensi. The first instar larvae were exposed to tirflumuron at LC50 level (0.0001 mg/l) in a continues exposure time. Among 1000 larvae listed 570 were passed to pupal stage (43% morality at the larvae of stage). The...

  12. Larva migrans cutânea: ocorrência de casos humanos e identificação de larvas de Ancylostoma spp em parque público do município de Taciba, São Paulo Cutaneous larva migrans: reports of pediatric cases and contamination by Ancylostoma spp larvae in public parks in Taciba, São Paulo State

    OpenAIRE

    Vamilton Alvares Santarém; Rogério Giuffrida; Gabriel Arantes Zanin

    2004-01-01

    Descreve-se a ocorrência de larva migrans cutânea em crianças de Taciba, São Paulo, Brasil, pelo contato com areia de parques públicos, onde observou-se larvas de Ancylostoma spp. A enfermidade foi controlada após adotar-se medidas educacionais sanitárias, desativação e isolamento dos locais para reduzir acesso de animais e troca de areia.Cutaneous larva migrans in children from Taciba, São Paulo, Brazil, was related to contact with sand in public squares, where Ancylostoma spp larvae were de...

  13. Unusual pseudomyiasis with Musca domestica (housefly) larvae in a child with chronic otitis media

    OpenAIRE

    Zafar Iqbal; Satish Chandra Sharma; Hiba Sami; Amit Kumar

    2016-01-01

    Myiasis is a disease caused by fly larvae and aural myiasis is a rare clinic condition often occurring in children or mentally retarded people. We report the case of an unusual presentation of a unilateral aural myiasis in a 3-year-old female child patient belonging to a slum with unilateral chronic otitis media caused by Musca domestica (housefly) larvae. Eight larvae were removed from the external auditory canal while five more larvae were located in the middle ear cavity and were removed t...

  14. Effect of gamma radiation on the Mediterranean flour moth, Ephestia Kuehniella, mature larvae and acceptability of irradiated larvae by Bracon hebetor female

    International Nuclear Information System (INIS)

    Mediterranean flour moth, Ephestia kuehniella, mature 5th instar larvae were exposed to gamma radiation dosages ranging from 50-350 Gy at 50 Gy increment and the effects of gamma radiation on pupation, adult emergence and sex ratio were investigated. In addition, effects of irradiation on the rate of development to pupae and adults and the acceptance of irradiated larvae by B. hebetor females were examined. Results showed that the radio-sensitivity of E. kuehniella larvae increased with increasing dose. Pupation was significantly affected at 100 Gy dose, and completely prevented at 350 Gy dose. Adult emergence was only slightly different from pupation; emergence was significantly affected at 100 Gy dose and completely prevented at 300 Gy dose. Irradiation also negatively affected the rate of development of larvae to pupae and adults. While more than 98% of control larvae pupated within 10 days of treatment, this ratio decreased to about 79% in larvae exposed to 50 Gy and less than 4% in larvae exposed to 100 Gy dose. The rate of development to the adult stage was also similarly affected. While 97% of control insects emerged as adults in the 1st 20 days of treatment, this ratio decreased to about 53, 2 and zero percent in larvae exposed to 50, 100 and 150 Gy dose respectively. In addition, irradiation significantly affected male: female ratio; sex ratio was skewed in favor of males, and at 250 Gy dose all emerged moths were males. Furthermore, irradiation had no adverse effect on the degree of acceptance of mature larvae to parasitization; irradiated insects were as acceptable to B. hebetor females as unirradiated ones. (author)

  15. Effect of gamma radiation on the Mediterranean flour moth, Ephestia Kuehniella, mature larvae and acceptability of irradiated larvae by Bracon hebetor females

    International Nuclear Information System (INIS)

    Mediterranean flour moth, Ephestia kuehniella, mature 5th instar larvae were exposed to gamma radiation dosages ranging from 50-350 Gy at 50 Gy increment and the effects of gamma radiation on pupation, adult emergence and sex ratio were investigated. In addition, effects of irradiation on the rate of development to pupae and adults and the acceptance of irradiated larvae by B. hebetor females were examined. Results showed that the radio-sensitivity of E. kuehniella larvae increased with increasing dose. Pupation was significantly affected at 100 Gy dose, and completely prevented at 350 Gy dose. Adult emergence was only slightly different from pupation; emergence was significantly affected at 100 Gy dose and completely prevented at 300 Gy dose. Irradiation also negatively affected the rate of development of larvae to pupae and adults. While more than 98% of control larvae pupated within 10 days of treatment, this ratio decreased to about 79% in larvae exposed to 50 Gy and less than 4% in larvae exposed to 100 Gy dose. The rate of development to the adult stage was also similarly affected. While 97% of control insects emerged as adults in the 1st 20 days of treatment, this ratio decreased to about 53, 2 and zero percent in larvae exposed to 50, 100 and 150 Gy dose respectively. In addition, irradiation significantly affected male: female ratio; sex ratio was skewed in favor of males, and at 250 Gy dose all emerged moths were males. Furthermore, irradiation had no adverse effect on the degree of acceptance of mature larvae to parasitization; irradiated insects were as acceptable to B. hebetor females as unirradiated ones. (author)

  16. Seasonal variation in toxicity of citral against Fasciola larva

    Institute of Scientific and Technical Information of China (English)

    Kumari Sunita; Pradeep Kumar; Dinesh Kumar Singh

    2014-01-01

    Objective:To test whether the larvicidal activity of citral against Fasciola varies by season. Methods:Mortality of Fasciola larva in different month of year (2011-2012) in in vitro and in vivo condition were observed at 2 h, 4 h, 6 h and 8 h exposure of citral. Results:In vitro toxicity of citral against redia was highest in between the June to August (8 h LC50: 2.58-2.62 mg/L), whereas against cercaria 8 h LC50 was in between 3.44-2.62 mg/L. Highest in vivo toxicity against redia was noted in between June to August (8h LC50: 4.20-5.09 mg/L). The lowest toxicity was observed from November to April. The highest temperature, free carbon dioxide, and lowest pH, dissolved oxygen were observed from June to August. Conclusions:The present study conclusively shows that varying a biotic factor can significantly alter the in vitro and in vivo toxicity of citral against sporocyst redia and cercaria larva.

  17. Pyrethroid resistance in Aedes aegypti larvae (Diptera: Culicidae) from Singapore.

    Science.gov (United States)

    Koou, Sin-Ying; Chong, Chee-Seng; Vythilingam, Indra; Ng, Lee-Ching; Lee, Chow-Yang

    2014-01-01

    We report the first comprehensive insecticide susceptibility status ofAedes aegypti (L.) larvae from Singapore. The study indicated that Ae. aegypti is susceptible to temephos, although resistance (RR50 = 1.29-4.43-fold) couldbe developing. Of high concern is the detection of moderate to high resistance to permethrin (RR50 = 29-47-fold) and etofenprox (RR50 = 14-34-fold). Biolarvicide Bacillus thuringiensis israelensis (Bti) remains effective. The insecticide susceptibility profile of Ae. aegypti larvae was found to be homogenous among the different sites studied across the island city. The addition of synergists piperonyl butoxide, S,S,S,-tributyl phosphorotrithioate, and triphenyl phosphate generally failed to enhance the toxicity of the insecticides investigated, suggesting an insignificant role of metabolic-based resistance, and a possible involvement of target site resistance. Further biochemical investigation of specific metabolic enzyme activities suggested that detoxifying enzymes, mono-oxygenases, esterases, glutathione S-transferases, and altered acetylcholinesterases, generally did not contribute to the resistance observed. This study clearly demonstrated that pyrethroid resistance is widespread among Ae. aegypti population and lowered susceptibility to organophosphates is developing. PMID:24605467

  18. Pathogenicity of Four Entomopathogenic Nematodes Species to G. mellonella Larvae

    Directory of Open Access Journals (Sweden)

    Pavel Hyrsl

    2011-06-01

    Full Text Available Entomopathogenic nematodes (EPNs of the genera Heterorhabditis and Steinernema are obligate and lethal insect parasites. In last decade they are widely used as biological control agents for pest insects of commercial crops, therefore research in this area is directly linked to agriculture. In this study, the pathogenicity of four nematode species (Heterorhabditis bacteriophora, Steinernema glaseri, Steinernema scarabaei and Steinernema feltiae was tested against Galleria mellonella larvae. Infective stage of EPNs together with their symbiotic bacteria kills insect host within 48 hours. The results show that mortality of insect host correlates with number of invaded infective juveniles (IJs. The invasion process is very fast, IJs enters insect host within a few hours. The importance of digestive tract as entering site was clearly demonstrated, larvae with empty gut are much more sensitive to nematode infection. Nemato-bacterial complex is very effective system overcoming insect immune defences. Encapsulation as the only one cellular reaction is activated, but in very low rate and was detected only during infection of H. bacteriophora.

  19. Vibrio harveyi effect under survival of Litopenaeus vannamei larvae

    Directory of Open Access Journals (Sweden)

    Gabriel Aguirre-Guzmán

    2013-06-01

    Full Text Available The culture of aquatic organisms show a high relevance in the human feeding and the culture activities can create artificial conditions that increase the growth and selection of specific bacteria. Vibrio species are normal bacteria’s from microflora of penaeid shrimp, those are opportunistic pathogens that can take advantage of the ecological changes generated for the culture of aquatic organisms and which may cause diseases, low survival and economic losses in the shrimp production. The aim of this research was to determine the variation in the survival of different larval substages (nauplius, zoea I-III, mysis I-III and postlarvae 1, of Pacific white shrimp Litopenaeus vannamei exposed at three doses [103 , 105 , and 107 colony-forming unit (CFU ml-1 [ of V. harveyi, by immersion (30 min as infection method. This species generated a significant low survival in larvae (p < 0.05 only in high doses (105 and 107 CFU ml-1 , where higher doses show the lowest values of survival. Larval substages and postlarvae 1 of shrimp showed sensitivity associate to the increase of Vibrio doses and this sensitivity decreased with the growth of larval substages and postlarvae 1. This information has high significance for the fisheries and aquaculture industry, which help to generate strategies to reduce the effects of V. harveyi with positive effect in growth and survival of the shrimp larvae and postlarvae 1.

  20. Otolith geochemistry does not reflect dispersal history of clownfish larvae

    Science.gov (United States)

    Berumen, M. L.; Walsh, H. J.; Raventos, N.; Planes, S.; Jones, G. P.; Starczak, V.; Thorrold, S. R.

    2010-12-01

    Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: “self-recruiters” spawned by parents on Kimbe Island and “immigrants” that had dispersed from distant reefs (>10 km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags.

  1. Phototoxicity of petroleum products to marine invertebrate larvae and niles

    International Nuclear Information System (INIS)

    Ultraviolet light can activate certain polycyclic aromatic hydrocarbons (PAHs), inducing the production of free radicals. In biological organisms these free radicals destroy tissues, causing up to a 4,000 fold increase in toxicity. This dramatic response is a potential marker for PAH contamination in environmental samples. Ultraviolet enhancement of toxicity has ecological relevance as well. An oil spill can release large amounts of PAHs into the marine environment. Oil spill assessments to date have not included observations of any phototoxic effect on pelagic larvae or juveniles of benthic or epibenthic invertebrates. In this study, larvae and juveniles of the bivalve, Mulinia lateralis and juveniles of the mysid shrimp, Mysidopsis bahia were exposed to individual PAHs, as well as the water accommodated fractions of several petroleum products to verify the ability of this method to detect PAHs in environmental samples, and to determine if phototoxicity is a concern during and after an oil spill. Significant phototoxicity was seen in both single chemical and petroleum product exposures. Swartz's EPAH model was not applicable to the authors' results. They hoped to show causality but were not fully successful due to the need to further develop the model with their species and expand the number of PAH analyzed

  2. Decapod larvae dynamics on Berlengas Biosphere Reserve (UNESCO - Portugal

    Directory of Open Access Journals (Sweden)

    Lénia Da Fonseca Alexandre Rato

    2014-05-01

    Total decapoda abundance ranged from 0,06 ind.m-3 in May 2011 to 64,28ind.m-3 in August 2012, and significantly different between summer/winter and winter/spring months (P(perm≤0,05. The data obtained on this study revealed that Infraorders Brachyura, Anomura and Caridea are the most common. All three are significantly different between months (P(perm≤0,05 but not between sampling stations (P(perm>0,05. Brachyuran abundance was significantly affected by the Oceanograhic Conditions (P(perm≤0,05. Abundances were higher in spring and summer months, when Chlorophyl a values (mg.m-3, Temperature (ºC and Salinity (ppt were also higher. Decapoda community is directly affected by the surrounding environmental conditions in Berlengas Biosphere Reserve and abundance might also be related with specific larvae release throughout the year. Each sampling station was considered a replica from the study area. The ecological importance of Berlengas was also verified by the presence of non-frequent larvae of Achelata and Stomatopoda.

  3. Histomorphogenesis of cranial nerves in Huso huso larvae.

    Science.gov (United States)

    Tavighi, Sherma; Saadatfar, Zohreh; Shojaei, Bahador; Behnam Rassouli, Morteza

    2016-01-01

    In this study the cranial nerves development of H. huso are explained from 1 to 54-days-old (1, 3, 6, 15, 21 and 54 days). Despite all the researches on fish brain, there are no study on nerves evolution on H. huso during their larvae life. For this research 40 samples of larvae H. huso were obtained (from each age, about six samples were selected). The specimens were maintained in fiberglass tank, then histological samples were taken from tissues and stained with hematoxylin and eosin for general histological studies using light microscope. According to the results, on 1 and 3-days-old, no nerve was observed. The terminal nerve and their dendrites were observed around the nasal cavity and the axons projected to different areas in forebrain especially around olfactory bulb diffusely, on 6-day-old fish. Also, olfactory, optic, oculomotor, trochlear, trigeminal, lateral line and vagus nerves were detected on 6-day-old fish, however two parts of lateral line nerve were separated on 54-day-old. Three nerves, profundus, facial and octaval were observed on 54-day-old, however, up to this age, epiphysial nerve was not observed. PMID:27482355

  4. The colonization dynamics of the gut microbiota in tilapia larvae.

    Directory of Open Access Journals (Sweden)

    Christos Giatsis

    Full Text Available The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an environmental factor is very complicated. Interactions between factors are difficult to separate and any response could be masked due to high inter-individual variation even for individuals that share a common environment. In this study we characterized and quantified the spatio-temporal variation in the gut microbiota of tilapia larvae, reared in recirculating aquaculture systems (RAS or active suspension tanks (AS. Our results showed that variation in gut microbiota between replicate tanks was not significantly higher than within tank variation, suggesting that there is no tank effect on water and gut microbiota. However, when individuals were reared in replicate RAS, gut microbiota differed significantly. The highest variation was observed between individuals reared in different types of system (RAS vs. AS. Our data suggest that under experimental conditions in which the roles of deterministic and stochastic factors have not been precisely determined, compositional replication of the microbial communities of an ecosystem is not predictable.

  5. The colonization dynamics of the gut microbiota in tilapia larvae.

    Science.gov (United States)

    Giatsis, Christos; Sipkema, Detmer; Smidt, Hauke; Verreth, Johan; Verdegem, Marc

    2014-01-01

    The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an environmental factor is very complicated. Interactions between factors are difficult to separate and any response could be masked due to high inter-individual variation even for individuals that share a common environment. In this study we characterized and quantified the spatio-temporal variation in the gut microbiota of tilapia larvae, reared in recirculating aquaculture systems (RAS) or active suspension tanks (AS). Our results showed that variation in gut microbiota between replicate tanks was not significantly higher than within tank variation, suggesting that there is no tank effect on water and gut microbiota. However, when individuals were reared in replicate RAS, gut microbiota differed significantly. The highest variation was observed between individuals reared in different types of system (RAS vs. AS). Our data suggest that under experimental conditions in which the roles of deterministic and stochastic factors have not been precisely determined, compositional replication of the microbial communities of an ecosystem is not predictable. PMID:25072852

  6. Otolith geochemistry does not reflect dispersal history of clownfish larvae

    KAUST Repository

    Berumen, Michael L.

    2010-07-01

    Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: "self-recruiters" spawned by parents on Kimbe Island and "immigrants" that had dispersed from distant reefs (>10 km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags. © 2010 Springer-Verlag.

  7. How did indirect development with planktotrophic larvae evolve?

    Science.gov (United States)

    Nielsen, Claus

    2009-06-01

    The two main types of theories for the evolution of the biphasic life cycles in marine invertebrates are discussed. The "intercalation" theories propose that the larval stages (planktotrophic or lecithotrophic) have evolved as specializations from the ancestral, direct life cycle. The opposing "terminal addition" theories propose that the ancestor was holopelagic and that the adult stage was added to the life cycle with the pelagic stage retained as a planktotrophic larva. It is emphasized that theories based on hypothetical ancestors that were unable to feed must be rejected. This applies to planula theories based on a compact planula. Various arguments against the theories that consider the feeding larvae as ancestral in the major eumetazoan lineages and in particular against the trochaea theory are discussed and found untenable. It is suggested that the "Cambrian explosion" was actually a rapid Ediacaran radiation of the eubilaterians that was made possible by the evolution of a tubular gut with all the resulting possibilities for new body plans. PMID:19556589

  8. The hemolymph proteome of fed and starved Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Björn Handke

    Full Text Available The co-operation of specialized organ systems in complex multicellular organisms depends on effective chemical communication. Thus, body fluids (like blood, lymph or intraspinal fluid contain myriads of signaling mediators apart from metabolites. Moreover, these fluids are also of crucial importance for immune and wound responses. Compositional analyses of human body fluids are therefore of paramount diagnostic importance. Further improving their comprehensiveness should increase our understanding of inter-organ communication. In arthropods, which have trachea for gas exchange and an open circulatory system, the single dominating interstitial fluid is the hemolymph. Accordingly, a detailed analysis of hemolymph composition should provide an especially comprehensive picture of chemical communication and defense in animals. Therefore we used an extensive protein fractionation workflow in combination with a discovery-driven proteomic approach to map out the detectable protein composition of hemolymph isolated from Drosophila larvae. Combined mass spectrometric analysis revealed more than 700 proteins extending far beyond the previously known Drosophila hemolymph proteome. Moreover, by comparing hemolymph isolated from either fed or starved larvae, we provide initial provisional insights concerning compositional changes in response to nutritional state. Storage proteins in particular were observed to be strongly reduced by starvation. Our hemolymph proteome catalog provides a rich basis for data mining, as exemplified by our identification of potential novel cytokines, as well as for future quantitative analyses by targeted proteomics.

  9. Sorghum, Miscanthus & Co: Energy crops as potential host plants of western corn rootworm larvae

    Directory of Open Access Journals (Sweden)

    Gloyna, Kai

    2014-02-01

    Full Text Available In a series of greenhouse experiments the host status and quality of 49 biofuel plants for the larvae of WCR were evaluated. The plants tested (18 species and varieties of Sorghum, 16 forage grasses, 6 Miscanthus genotypes, 6 Panicum varieties and 3 broadleaf species were grown for at least three weeks before they were used in the bioassays. The insects used in the experiments were obtained from a non diapausing laboratory strain originally from the US and maintained by BTL since 2006. Only neonate larvae (not older than 24 hours were used in the bioassays. In each experiment up to six species or varieties of plants were tested each with 10 replicates (containers. A susceptible maize variety was used as a positive control in each experiment. Each plant container was infested with ten neonate WCR larvae using a fine art brush. After inoculation the plants were not watered for at least 24 hours to facilitate the establishment of the larvae. The experiments were terminated after 18 days. To extract surviving larvae the soil and roots of test plants were carefully examined by hand and then transferred to a modified MacFadyen heat extractor with an extraction temperature of 45 °C. To assess the host quality the number of larvae recovered, the widths of their head capsules and dry weights were recorded. The larvae were dried at 40 °C for at least 72 hours and then weighed on an electronic micro balance. Of the 21 forage and switch grasses examined 16 hosted WCR larvae. However, the percentage of larvae that survived for 18 days, their dry weights and head capsule widths were significantly less than that recorded for larvae that developed on maize roots. The roots of most (i.e. 15 of the 18 Sorghum species or varieties tested were unsuitable for the development of WCR larvae. For the remaining three Sorghum species a maximum of only two larvae (of 100 inoculated were recovered. These results indicate that species of Sorghum are very poor quality

  10. Effects of copper sulfate on ion balance and growth in tilapia larvae (Oreochromis mossambicus).

    Science.gov (United States)

    Wu, S M; Jong, K J; Kuo, S Y

    2003-10-01

    Newly hatched tilapia larvae were exposed to sublethal concentrations of Cu2+ (0, 30, 50, and 100 microg/L) and lethal concentrations of Cu2+ (200 and 400 microg/L) for 24-96 h. The interaction of the exposure dose and time was related to the Cu2+ accumulation rate, which showed a higher accumulation rate with sublethal concentrations of Cu2+ within 24 h compared to the other treatments. Furthermore, Cu2+ contents in the whole body of larvae significantly increased following Cu2+ exposure times up to 96 h. Cu2+ in the medium produced a dose-response effect on Na+ and K+ contents in larvae after 96 h of exposure time. Changes in Ca2+ contents statistically significantly decreased and were shown to be dose-responsive for larval exposure times exceeding 72 h. Changes of Ca2+ contents were more sensitive than those of Na+ and K+ with Cu2+ treatment of early larvae. Notably Na+ and K+ contents showed significant increases of 17-23% in larvae exposed to low concentrations of Cu2+ (30-50 microg/L) for 24-72 h as compared to control larvae. Cu2+ caused no significant effect on body Cl- content or osmolality except at 100 microg/L Cu2+ for 24 h in tilapia larvae as compared to the control. However, there was a restoration phenomenon in larvae exposed to 100 microg/L Cu2+ for longer than 72 h. The water content of larvae exposed to Cu2+ for 96 h significantly decreased. The yolk absorption rate of tilapia larvae was significantly suppressed when they were exposed to Cu2+ medium containing 30, 50, 100, 200, or 400 Cu2+ microg/L from 72 h post transfer. These results obviously show that larvae are sensitive to Cu2+ during early development. PMID:14674589

  11. Comparative analysis of hemolymph proteome maps in diapausing and non-diapausing larvae of Sesamia nonagrioides

    Directory of Open Access Journals (Sweden)

    Pérez-Hedo Meritxell

    2012-09-01

    Full Text Available Abstract Background Sesamia nonagrioides is a noctuid that feeds on maize, sugar cane and sorghum in North Africa and Southern Europe. Larvae reared under long day conditions pupate after 5 or 6 larval instars, whereas larvae reared under short day conditions enter diapause and undergo up to 12 molts before dying or pupating. To better understand the mechanism of larval development and diapause, we identified proteins with different expressions in the sixth instar of diapausing and non-diapausing larvae. Results A total of 52 differentially regulated proteins were detected in the hemolymph of the diapausing or non-diapausing larvae at the beginning or end of the sixth instar. From these proteins, 11 were identified by mass spectrometry (MALDI-TOF MS or MALDI-TOF/TOF MS/MS: 5 were upregulated in the hemolymph of non-diapausing larvae and 6 in the hemolymph of the diapausing larvae. Interestingly, some proteins were expressed only in non-diapausing larvae but none was expressed only in the hemolymph of diapausing larvae. The possible functions of some of these proteins related to diapause maintenance or to larval-pupal metamorphosis are discussed. Conclusions The 2-DE proteomic map of S. nonagrioides hemolymph shows differential protein expression in diapausing and non-diapausing larvae. Some proteins that showed higher expression in the diapausing larvae at the end of the sixth instar could be involved in JH level maintenance thus in the diapause status maintenance. On the contrary, other proteins that showed the highest expression or that were expressed only in the non-diapausing larvae could be involved in larval-pupal metamorphosis.

  12. Helminths Parasite Larvae collected from Arabian Gulf Fish. 4. Description of four Larvae including two Metacercarae, one Didymozoid and one Acanthocephalan from Emirati Coasts

    International Nuclear Information System (INIS)

    Four helminth larvae from different fish hosts caught from Emirate coasts are described. Two are metacercariae related to genus Southampton's, type (I) and (II). Type (I) was found encysted in body cavities of the Indian halibut Psettodes erumei and the areolate grouper Epinephelus areolatusu and type (II) in the golden stripped goatfish Mulloides flavolineatus. The third larva is related to Acanthocephala and identified as Serrasentis sagittifer. It was collected from the body cavity of the spotted lizard fish Saurida undosquamius. The fourth larva belongs to the didymozoid trematodes, and was found infecting the kidneys of different hosts, such as Saurida undosquamis, the Jack pomfret Parastromateus niger and mackerel tuna Euthynnus affins. The larva related to Stephanostomum type (I) and type (II) and the dydimozoid type are described for the first time in the Arabian Gulf. (author)

  13. Effect of bodily fluids from honey bee (Apis mellifera) larvae on growth and genome-wide transcriptional response of the causal agent of American Foulbrood disease (Paenibacillus larvae).

    Science.gov (United States)

    De Smet, Lina; De Koker, Dieter; Hawley, Alyse K; Foster, Leonard J; De Vos, Paul; de Graaf, Dirk C

    2014-01-01

    Paenibacillus larvae, the causal agent of American Foulbrood disease (AFB), affects honey bee health worldwide. The present study investigates the effect of bodily fluids from honey bee larvae on growth velocity and transcription for this Gram-positive, endospore-forming bacterium. It was observed that larval fluids accelerate the growth and lead to higher bacterial densities during stationary phase. The genome-wide transcriptional response of in vitro cultures of P. larvae to larval fluids was studied by microarray technology. Early responses of P. larvae to larval fluids are characterized by a general down-regulation of oligopeptide and sugar transporter genes, as well as by amino acid and carbohydrate metabolic genes, among others. Late responses are dominated by general down-regulation of sporulation genes and up-regulation of phage-related genes. A theoretical mechanism of carbon catabolite repression is discussed. PMID:24586572

  14. Hyaluronidase from infective Ancylostoma hookworm larvae and its possible function as a virulence factor in tissue invasion and in cutaneous larva migrans.

    OpenAIRE

    Hotez, P. J.; Narasimhan, S; HAGGERTY, J; Milstone, L; Bhopale, V; Schad, G A; Richards, F F

    1992-01-01

    During skin penetration, infective hookworm larvae encounter hyaluronic acid as they migrate between epidermal keratinocytes and through the ground substance of the dermis. A hyaluronidase would facilitate passage through the epidermis and dermis during larval invasion. Zoonotic hookworm larvae of the genus Ancylostoma were shown to contain a hyaluronidase activity that migrated on modified sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) hyaluronic acid gels with an appar...

  15. Chemical Composition and Food Potential of Pachymerus nucleorum Larvae Parasitizing Acrocomia aculeata Kernels.

    Science.gov (United States)

    Alves, Ariana Vieira; Sanjinez Argandoña, Eliana Janet; Linzmeier, Adelita Maria; Cardoso, Claudia Andrea Lima; Macedo, Maria Lígia Rodrigues

    2016-01-01

    Insect consumption as food is culturally practiced in various regions of the world. In Brazil, there are more than 130 species of edible insects registered, from nine orders, among which stands out the Coleoptera. The larva of the beetle Pachymerus nucleorum Fabricius, 1792, grows into the bocaiuva fruit (Acrocomia aculeata (Jacq.) Lodd. Ex Mart., 1845), which has proven nutritional quality. The aim of this work was to evaluate the nutritional potential of P. nucleorum larvae compared to bocaiuva kernels for human consumption. Proteins were the second largest portion of the larvae nutritional composition (33.13%), with percentage higher than the bocaiuva kernels (14.21%). The larval lipid content (37.87%) was also high, very close to the kernels (44.96%). The fraction corresponding to fatty acids in the oil extracted from the larvae was 40.17% for the saturated and 46.52% for the unsaturated. The antioxidant activity value was 24.3 uM trolox/g of oil extracted from larvae. The larvae tryptic activity was 0.032±0.006 nmol BAPNA/min. Both the larvae and the bocaiuva kernel presented absence of anti-nutritional factors. These results favor the use of P. nucleorum larvae as food, which are a great protein and lipid sources with considerable concentrations of unsaturated fatty acids compared to the bocaiuva kernel. PMID:27031500

  16. Chemical Composition and Food Potential of Pachymerus nucleorum Larvae Parasitizing Acrocomia aculeata Kernels.

    Directory of Open Access Journals (Sweden)

    Ariana Vieira Alves

    Full Text Available Insect consumption as food is culturally practiced in various regions of the world. In Brazil, there are more than 130 species of edible insects registered, from nine orders, among which stands out the Coleoptera. The larva of the beetle Pachymerus nucleorum Fabricius, 1792, grows into the bocaiuva fruit (Acrocomia aculeata (Jacq. Lodd. Ex Mart., 1845, which has proven nutritional quality. The aim of this work was to evaluate the nutritional potential of P. nucleorum larvae compared to bocaiuva kernels for human consumption. Proteins were the second largest portion of the larvae nutritional composition (33.13%, with percentage higher than the bocaiuva kernels (14.21%. The larval lipid content (37.87% was also high, very close to the kernels (44.96%. The fraction corresponding to fatty acids in the oil extracted from the larvae was 40.17% for the saturated and 46.52% for the unsaturated. The antioxidant activity value was 24.3 uM trolox/g of oil extracted from larvae. The larvae tryptic activity was 0.032±0.006 nmol BAPNA/min. Both the larvae and the bocaiuva kernel presented absence of anti-nutritional factors. These results favor the use of P. nucleorum larvae as food, which are a great protein and lipid sources with considerable concentrations of unsaturated fatty acids compared to the bocaiuva kernel.

  17. INDEKS ENTOMOLOGI DAN KERENTANAN LARVA Aedes aegypti TERHADAP TEMEFOS DI KELURAHAN KARSAMENAK KECAMATAN KAWALU KOTA TASIKMALAYA

    OpenAIRE

    Hubullah Fuadzy; Joni Hendri

    2015-01-01

    AbstrakSalah satu upaya pengendalian vektor nyamuk Aedes aegypti adalah menggunakan larvasida sintetis seperti temefos. Pemanfaatan temefos secara terus menerus dan berulang merupakan faktor risiko terjadinya resistensi. Tujuan penelitian ini adalah untuk menentukan indeks entomologi dan status kerentanan larva Ae. aegypti terhadap temefos di Kelurahan Karsamenak Kecamatan Kawalu Kota Tasikmalaya. Jenis penelitian adalah eksperimen dengan rancangan acak lengkap. Populasi adalah larva nyamuk A...

  18. Xenodiagnóstico na Habronemose dos Equídeos: estudo das larvas do Helminto

    Directory of Open Access Journals (Sweden)

    Jônio F. de Sales

    1945-02-01

    Full Text Available Xenodiagnosis for habronemosis was 96,6% positive in 87 stud horses at Instituto Oswaldo Cuz, Rio de Janeiro, Brazil, from July-November, 1944. The A A. were unable to identify the Habronema larvae obtained from parasitider fly maggots. Measurements and drawings of the larvae are presented.

  19. Black soldier fly (Diptera: Stratiomyidae) larvae reduce Escherichia coli in dairy manure.

    Science.gov (United States)

    Liu, Qiaolin; Tomberlin, Jeffery K; Brady, Jeff A; Sanford, Michelle R; Yu, Ziniu

    2008-12-01

    Escherichia coli labeled with a green fluorescent protein was inoculated into sterile dairy manure at 7.0 log cfu/g. Approximately 125 black soldier fly larvae were placed in manure inoculated and homogenized with E. coli. Manure inoculated with E. coli but without black soldier fly larvae served as the control. For the first experiment, larvae were introduced into 50, 75, 100, or 125 g sterilized dairy manure inoculated and homogenized with E. coli and stored 72 h at 27 degrees C. Black soldier fly larvae significantly reduced E. coli counts in all treatments. However, varying the amount of manure provided the black soldier fly larvae significantly affected their weight gain and their ability to reduce E. coli populations present. For the second experiment, larvae were introduced into 50 g manure inoculated with E. coli and stored for 72 h at 23, 27, 31, or 35 degrees C. Minimal bacterial growth was recorded in the control held at 35 degrees C and was excluded from the analysis. Black soldier fly larvae significantly reduced E. coli counts in manure held at remaining temperatures. Accordingly, temperature significantly influenced the ability of black soldier fly larvae to develop and reduce E. coli counts with greatest suppression occurring at 27 degrees C. PMID:19161696

  20. The intestinal bacterial community in the food waste-reducing larvae of Hermetia illucens.

    Science.gov (United States)

    Jeon, Hyunbum; Park, Soyoung; Choi, Jiyoung; Jeong, Gilsang; Lee, Sang-Beom; Choi, Youngcheol; Lee, Sung-Jae

    2011-05-01

    As it is known that food waste can be reduced by the larvae of Hermetia illucens (Black soldier fly, BSF), the scientific and commercial value of BSF larvae has increased recently. We hypothesised that the ability of catabolic degradation by BSF larvae might be due to intestinal microorganisms. Herein, we analysed the bacterial communities in the gut of BSF larvae by pyrosequencing of extracting intestinal metagenomic DNA from larvae that had been fed three different diets. The 16S rRNA sequencing results produced 9737, 9723 and 5985 PCR products from larval samples fed food waste, cooked rice and calf forage, respectively. A BLAST search using the EzTaxon program showed that the bacterial community in the gut of larvae fed three different diets was mainly composed of the four phyla with dissimilar proportions. Although the composition of the bacterial communities depended on the different nutrient sources, the identified bacterial strains in the gut of BSF larvae represented unique bacterial species that were unlike the intestinal microflora of other insects. Thus, our study analysed the structure of the bacterial communities in the gut of BSF larvae after three different feedings and assessed the application of particular bacteria for the efficient degradation of organic compounds. PMID:21267722

  1. Larvae of North American Eukiefferiella and Tvetenia (Diptera: Chironomidae). Bulletin No. 452.

    Science.gov (United States)

    Bode, Robert W.

    "Eukiefferiella" and "Tvetenia" are closely related genera belonging to the subfamily Orthocladiinae within the Chironomidae, a family of non-biting midges. All known larvae in these genera are aquatic, being found predominantly in running water. Most species prefer cold, swift-flowing, well-oxygenated streams. Although larvae and pupae of these…

  2. Genes Expressed Differentially in Hessian Fly Larvae Feeding in Resistant and Susceptible Plants

    Science.gov (United States)

    Chen, Ming-Shun; Liu, Sanzhen; Wang, Haiyan; Cheng, Xiaoyan; El Bouhssini, Mustapha; Whitworth, R. Jeff

    2016-01-01

    The Hessian fly, Mayetiola destructor, is a destructive pest of wheat worldwide and mainly controlled by deploying resistant cultivars. In this study, we investigated the genes that were expressed differentially between larvae in resistant plants and those in susceptible plants through RNA sequencing on the Illumina platform. Informative genes were 11,832, 14,861, 15,708, and 15,071 for the comparisons between larvae in resistant versus susceptible plants for 0.5, 1, 3, and 5 days, respectively, after larvae had reached the feeding site. The transcript abundance corresponding to 5401, 6902, 8457, and 5202 of the informative genes exhibited significant differences (p ≤ 0.05) in the respective paired comparisons. Overall, genes involved in nutrient metabolism, RNA and protein synthesis exhibited lower transcript abundance in larvae from resistant plants, indicating that resistant plants inhibited nutrient metabolism and protein production in larvae. Interestingly, the numbers of cytochrome P450 genes with higher transcript abundance in larvae from resistant plants were comparable to, or higher than those with lower transcript abundance, indicating that toxic chemicals from resistant plants may have played important roles in Hessian fly larval death. Our study also identified several families of genes encoding secreted salivary gland proteins (SSGPs) that were expressed at early stage of 1st instar larvae and with more genes with higher transcript abundance in larvae from resistant plants. Those SSGPs are candidate effectors with important roles in plant manipulation. PMID:27529231

  3. The larva of Tricholeon relictus Hölzel & Monserrat, 2002 a synanthropic antlion (Neuroptera, Myrmeleontidae).

    Science.gov (United States)

    Acevedo, Fernando; Badano, Davide; Monserrat, Víctor J

    2014-01-01

    The larva of Tricholeon relictus, a Spanish endemic antlion of Afrotropical affinities, is described and illustrated for the first time also providing a comparison with the only other European member of the tribe Dendroleontini, Dendroleon pantherinus. The larva of this species is synanthropic but probably originally lived in cave-like habitats. PMID:25081458

  4. Entomopathogenic fungi disturbed the larval growth and feeding performance of Ocinara varians (Lepidoptera: Bombycidae) larvae

    Institute of Scientific and Technical Information of China (English)

    Abid Hussain; Ming-Yi Tian; Yu-Rong He; Sohail Ahmed

    2009-01-01

    Feeding experiments using three strains of entomopathogenic fungi, Beauveria bassiana, Metarhizium anisopliae and Isaria fumosorosea were conducted with newly moulted 3rd-5th instar Ocinara varians Walker larvae in the laboratory. The mortality of larvae immersed individually in spore suspension (1×10~7 spores/mL) of all the strains was > 80% except 5th instar larvae treated with M. anisopliae which transformed into pupae, but did not result in adult emergence. The growth (total body mass), consumption, relative consumption rate and relative growth rate, were reduced at all three larval stages, while developmental time was extended in infected larvae with concurrent significant increase in approximate digestibility in infected larvae. Conversion of digested food (ECD) and ingested food (ECI) values declined in infected larvae as compared to the healthy larvae (control). The 5th instar larvae treated with M. anisopliae showed higher ECD and ECI values than control. Based on mortality and growth inhibition it can be suggested that all the studied fungal strains have a high potential for biocontrol and could be developed into biocontrol agents against O. varians.

  5. The potential for cryopreserving larvae of the sea urchin, Evechinus chloroticus.

    Science.gov (United States)

    Adams, Serean L; Hessian, Paul A; Mladenov, Philip V

    2006-02-01

    Larvae of the sea urchin, Evechinus chloroticus, at varying stages of development, were assessed for their potential to survive cryopreservation. Ethylene glycol (EG) and dimethyl sulphoxide (Me2SO), at concentrations of 1-2 M, were evaluated as cryoprotectants (CPAs) in freezing regimes initially based on methods established for freezing larvae of other sea urchin species. Subsequent work varied cooling rate, holding temperature, holding time, and plunge temperature. Ethylene glycol was less toxic to larvae than Me2SO. However, no larvae survived freezing and thawing in EG. Larvae frozen in Me2SO at the gastrula stage and 4-armed pluteus stage regained motility post-thawing. The most successful freezing regime cooled straws containing larvae in 1.5 M Me2SO from 0 to -35 degrees C at 2.5 degrees C min(-1), held at -35 degrees C for 5 min, then plunged straws into liquid nitrogen. Motility was high 2-4 h post-thawing using this regime but decreased markedly within 24 h. Some 4-armed pluteus larvae that survived beyond this time developed through to metamorphosis and settled. Different Me2SO concentrations and supplementary trehalose did not improve long-term survival. Large variation in post-thaw survival was observed among batches of larvae produced from different females. PMID:16321369

  6. Multi-year survival of sugarbeet root maggot (Tetanops myopaeformis) larvae in cold storage

    Science.gov (United States)

    Sugarbeet root maggots (Tetanops myopaeformis), as third-instar larvae have been successfully maintained in cold (6 ± 1ºC) storage for up to six years. To test the hypothesis that this long term survival in storage is facilitated by larvae undergoing prolonged diapause, comparative studies on respir...

  7. Internal Lipids of Sugarbeet Root Maggot (Tetanops myopaeformis) Larvae: Effects of Multi-year Cold Storage

    Science.gov (United States)

    Sugarbeet root maggots, Tetanops myopaeformis (Röder), survive more than five years of laboratory cold (6oC) storage as mature third-instar larvae. To quantify energy costs associated with prolonged storage, internal lipids of larvae stored for 1, 2, 3, and 5 years were compared and characterized wi...

  8. [Otic myiasis in a newborn caused by Calliphoridae larvae of the genus Phaenicia].

    Science.gov (United States)

    Bowe Douglas, L; Amaro Trapaga, E; Sotolongo Guerra, F; Alonso Bermudez, P

    1977-01-01

    A 55-day-old newborn with an intense otitis haemorrhagica caused by a Calliphoridae larva of the genus Phaenicia is presented. During an ear lavage the larva was removed. The patient was admitted and once the genus was known he underwent a specific treatment and was discharged completely cured. PMID:356136

  9. Structure and occurrence of cyphonautes larvae (Bryozoa, Ectoprocta)

    DEFF Research Database (Denmark)

    Nielsen, Claus; Worsaae, Katrine

    2010-01-01

    We have studied larvae of the freshwater ctenostome Hislopia malayensis with scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and LM of serial sections. Some additional observations on larvae of M. membranacea using SEM and CLSM are also reported. The overall configu...

  10. Estimating reproductive success of Aethina tumida (Coleoptera: Nitidulidae) in honey bee colonies by trapping emigrating larvae.

    Science.gov (United States)

    Arbogast, Richard T; Torto, Baldwyn; Willms, Steve; Fombong, Ayuka T; Duehl, Adrian; Teal, Peter E A

    2012-02-01

    The small hive beetle (Aethina tumida Murray) is a scavenger and facultative predator in honey bee colonies, where it feeds on pollen, honey, and bee brood. Although a minor problem in its native Africa, it is an invasive pest of honey bees in the United States and Australia. Adult beetles enter bee hives to oviposit and feed. Larval development occurs within the hive, but mature larvae leave the hive to pupate in soil. The numbers leaving, which can be estimated by trapping, measure the reproductive success of adult beetles in the hive over any given period of time. We describe a trap designed to intercept mature larvae as they reach the end of the bottom board on their way to the ground. Trap efficiency was estimated by releasing groups of 100 larvae into empty brood boxes and counting the numbers trapped. Some larvae escaped, but mean efficiency ranged from 87.2 to 94.2%. We envision the trap as a research tool for study of beetle population dynamics, and we used it to track numbers of larvae leaving active hives for pupation in the soil. The traps detected large increases and then decreases in numbers of larvae leaving colonies that weakened and died. They also detected small numbers of larvae leaving strong European and African colonies, even when no larvae were observed in the hives. PMID:22525070

  11. Contest-Behavior of Maize Weevil Larvae when Competing within Seeds

    Science.gov (United States)

    Food limitation induces severe competition for obligate seed-feeding insect larvae that are unable to leave the seed selected by their mother. The number of eggs laid per seed and the number of larvae hatched from the eggs determine whether larval behavior within the seed will be of the scramble or ...

  12. Comparison of in vitro methods for the production of Paenibacillus larvae endospores.

    Science.gov (United States)

    Alvarado, Israel; Elekonich, Michelle M; Abel-Santos, Ernesto; Wing, Helen J

    2015-09-01

    Paenibacillus larvae endospores are the infectious particles of the honey bee brood disease, American Foulbrood. We demonstrate that our previously published protocol (Alvarado et al., 2013) consistently yields higher numbers and purer preparations of P. larvae endospores, than previously described protocols, regardless of the strain tested (B-3650, B-3554 or B-3685). PMID:26130193

  13. Proteome analysis of Paenibacillus larvae reveals the existence of a putative S-layer protein.

    Science.gov (United States)

    Fünfhaus, Anne; Genersch, Elke

    2012-04-01

    Honey bee pathology has attracted much interest recently due to the problems with honey bee declines in many regions of the world. American Foulbrood (AFB) caused by Paenibacillus larvae is the most devastating bacterial brood disease of the Western honey bee (Apis mellifera) causing considerable economic losses to beekeepers worldwide. AFB outbreaks are mainly caused by two differentially virulent genotypes of P. larvae, P. larvae ERIC I and ERIC II. To better understand AFB pathogenesis and to complement already existing data from the genetic level we aimed at obtaining expression data from the protein level. We successfully developed a protocol for two-dimensional proteome analysis of P. larvae with subsequent mass-spectrometry based protein sequencing. Based on the obtained master protein maps of P. larvae genotypes ERIC I and II we identified the dominantly expressed cytosolic proteins of both genotypes, some of them presumably linked to pathogenesis and virulence. Comparing the master maps of both genotypes revealed differentially expressed proteins, i.e. a putative S-layer protein which is expressed by P. larvae ERIC II but absent from the proteome of P. larvae ERIC I. The implications of our findings for pathogenesis of AFB and virulence of P. larvae will be discussed. PMID:23757273

  14. Protocols to test the activity of antimicrobial peptides against the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Khilnani, Jasmin C; Wing, Helen J

    2015-10-01

    Paenibacillus larvae is the causal agent of the honey bee disease American Foulbrood. Two enhanced protocols that allow the activity of antimicrobial peptides to be tested against P. larvae are presented. Proof of principle experiments demonstrate that the honey bee antimicrobial peptide defensin 1 is active in both assays. PMID:26210039

  15. Secreted and immunogenic proteins produced by the honey bee bacterial pathogen, Paenibacillus larvae

    Science.gov (United States)

    American Foulbrood is a severe disease affecting larvae of honeybee Apis mellifera, causing significant decrease in the honeybee population, beekeeping industries and agricultural production. In spite of its importance, little is known about the virulence factors secreted by Paenibacillus larvae dur...

  16. Molecular endocrine changes of Gh/Igf1 axis in gilthead sea bream (Sparus aurata L.) exposed to different environmental salinities during larvae to post-larvae stages.

    Science.gov (United States)

    Mohammed-Geba, Khaled; Yúfera, Manuel; Martínez-Rodríguez, Gonzalo; Mancera, Juan Miguel

    2016-08-01

    The influence of acclimation of the euryhaline gilthead sea bream (Sparus aurata) larvae/post-larvae to brackish water on growth, energetic contents, and mRNA levels of selected hormones and growth-regulating hypothalamic neurohormones was assessed. Specimens from 49 days post-hatching were acclimated during 28 days to two different environmental salinities: 38 and 20 psu (as brackish water). Both groups were then transferred to 38 psu and acclimated for an additional week. Early juveniles were sampled after 28 days of acclimation to both salinities and one week after transfer to 38 psu. Pituitary adenylate cyclase-activating peptide (adcyap1; pacap), somatostatin-I (sst1), growth hormone (gh1), insulin-like growth factor-I (igf1), and prolactin (prl) mRNA expression were all studied by QPCR. Post-larvae acclimated to 20 psu showed better growth performance and body energetic content than post-larvae maintained at 38 psu. prl, adcyap1, and igf1 mRNA expression levels increased in 20-psu-acclimated post-larvae but decreased upon transfer to 38 psu. GH1 expression did not show significant changes under both experimental conditions. Our results suggested an enhanced general performance for post-larvae in brackish water, supported by the actions of adcyap1, igf1, and prl. PMID:26947706

  17. Larvae of gryporhynchid cestodes (Cyclophyllidea) from fish: a review.

    Science.gov (United States)

    Scholz, Tomás; Bray, Rodney A; Kuchta, Roman; Repová, Radmila

    2004-06-01

    Larvae (metacestodes) of tapeworms of the cyclophyllidean family Gryporhynchidae (previously included in the Dilepididae) occur in different internal organs of fresh- and brackish water fish (110 fish species of 27 families in 12 orders reported), which serve as the second intermediate hosts. The species composition, spectrum of fish hosts, sites of infection, and geographical distribution of gryporhynchids recorded from fish are reviewed here on the basis of literary data and examination of extensive material from helminthological collections. Metacestodes of the following genera have been found in fish: Amirthalingamia Bray, 1974 (1 species), Ascodilepis Guildal, 1960 (1), Cyclustera Fuhrmann, 1901 (4), Dendrouterina Fuhrmann, 1912 (1), Glossocercus Chandler, 1935 (3), Neogryporhynchus Baer et Bona, 1960 (1), Paradilepis Hsü, 1935 (5), Parvitaenia Burt, 1940 (2), and Valipora Linton, 1927 (3). However, most published records concern only three species, namely Neogryporhynchus cheilancristrotus (Wedl, 1855) from the intestinal lumen, Paradilepis scolecina (Rudolphi, 1819) from the liver and mesenteries, and Valipora campylancristrota (Wedl, 1855) from the gall bladder of cyprinids and other fish in the Palaearctic Region. Data on other species as well as reports from other regions are very scarce and almost no information is available from Australia, tropical Asia and South America. A recent study of gryporhynchid metacestodes from Mexico (Scholz and Salgado-Maldonado 2001), which reported 13 species, suggested that they may be more common than indicated by records in the literature. Although only a few cases of pathogenic influence of larvae on fish hosts have been reported, the veterinary importance of gryporhynchids remains to be assessed on the basis of more detailed studies. The data available indicate a strict host and site specificity of some species whereas others occur in a wide spectrum of fish hosts and are not strictly site-specific. Evaluation of

  18. Nematodes parasitic in fishes of cenotes (= sinkholes) of the Peninsula of Yucatan, Mexico. Part 2. Larvae.

    Science.gov (United States)

    Moravec, F; Vivas-Rodríguez, C; Scholz, T; Vargas-Vázquez, J; Mendoza-Franco, E; Schmitter-Soto, J J; González-Solís, D

    1995-01-01

    This paper comprises a systematic survey of larval nematodes collected from fishes from cenotes (= sinkholes) of the Peninsula of Yucatan, southern Mexico, in 1993-1994. Larvae of the following nine species were recorded: Physocephalus sexalatus, Acuariidae gen. sp., Spiroxys sp., Falcaustra sp., Hysterothylacium cenotae, Contracaecum sp. Type 1, Contracaecum sp. Type 2, Goezia sp., and Eustrongylides sp. Larvae of P. sexalatus are recorded from fishes (Rhamdia guatemalensis) for the first time. The larvae are briefly described and illustrated and problems concerning their morphology, taxonomy, hosts and geographical distribution are discussed. Adults of these larvae are parasitic in piscivorous fishes, reptiles, birds and mammals (definitive hosts). Fishes harbouring the larvae of these parasites serve as paratenic hosts, being mostly an important source of infection for the definitive hosts. PMID:8774773

  19. Effects of pesticides on DNA and protein of shrimp larvae Litopenaeus stylirostris of the California Gulf.

    Science.gov (United States)

    Galindo Reyes, J Guillermo; Leyva, Nancy R; Millan, Olivia A; Lazcano, Guadalupe A

    2002-10-01

    Recently, diverse pathologies and massive mortalities have been presented in shrimp hatcheries located along the California Gulf; therefore, toxic responses of shrimp larvae were used as biomarkers of pesticide pollution, because in this region intensive agriculture is practiced. Shrimp larvae were exposed to DDT, azinphosmethyl, permethrine, parathion, chlorpyrifos, malathion, endosulfan, and carbaryl, in order to determine LC50, DNA adducts and/or breaks, and total protein in larvae. The results indicate reductions in protein and DNA in larvae exposed to these pesticides, and in those exposed to DDT, breaks and/or adducts were registered. It is possible that pesticide pollution is a cause of these problems, because reduction in protein indicates a decrease in larvae growth rate and DNA breaks or adducts have been related to pathologies and carcinogenesis in many aquatic organisms. PMID:12568452

  20. Composting poultry manure by fly larvae (Musca domestica) eliminates Campylobacter jejuni from the manure

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Hald, Birthe

    2013-01-01

    Introduction The common house fly, Musca domestica (Md) is an important carrier of zoonotic agents, and Campylobacter jejuni is one that may be transmitted between animals and humans by flies. Colonized animals shed the bacteria in feces where larval stages of Md flies develops. Aim of the present...... study To monitor fly larvae composting of poultry manure artificially contaminated with C. jejuni, and to investigate a possible transmission route of C. jejuni from the manure through the fly larvae to the adult fly. Conclusions The addition of fly larvae both accelerated the degradation of manure and...... C. jejuni. Pupae or newly hatched flies were not carriers of C. jejuni although larvae were grown in contaminated manure. Impact When composting poultry manure with Md fly larvae, it is possible both to reduce the amount of waste and to sanitize it from C. jejuni, thereby reducing the risk of...

  1. Prey attraction as a possible function of bioluminescence in the larvae of Pyrearinus termitilluminans (Coleoptera: Elateridae

    Directory of Open Access Journals (Sweden)

    Kent H. Redford

    1982-01-01

    Full Text Available Elaterid beetle larvae. Pyrearinus termitilluminans (sp.n., Costa, 1982. live in termite mounds in central Brazil. Each larva produces light in the segment immediately behind its head. Larvae were observed to luminesce only during the first weeks of the rainy season, the same times as the ant and termite alate flights. Alates, apparently attracted to P. termitilluminans larval lights, serve as an important food source for the larvae. The prey-catching and food-storing behavior and the phenomenon of bioluminescence are apparently an evolutionary response by P. termitilluminans larvae to a short, rich pulse of food. Prey attraction as a probable cause for luminescence has been suggested only twice before.

  2. Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

    Directory of Open Access Journals (Sweden)

    Sacchi L.

    2001-06-01

    Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

  3. Influence of low temperature on rate of development of Meloidogyne incognita and M. hapla larvae.

    Science.gov (United States)

    Vrain, T C; Barker, K R; Holtzman, G I

    1978-04-01

    Development of Meloidogyne incognita and M. hapla larvae in clover roots was studied at 20, 16, 12, and 8 C in growth chambers and in the field from fall through spring, in North Carolina. Larvae of both species invaded roots and developed at 20, 16, and 12 C, but not at 8 C. The time necessary to complete the larval stages at each temperature was determined. The minimal temperature for development of M. incognita larvae was 10.08 C and 8.8 C for M. hapla larvae. In the field, soil temperature at 10 cm deep was favorable for development of larvae until the end of November, and again from February on. All stages of the nematodes survived freezing temperatures in the roots. Reproduction of both species was evident in March or Apri1 after inoculation and accumulation of 8,500 to 11,250 degree-hours. PMID:19305832

  4. Immunization of lambs against Oesophagostomum columbianum, using irradiated third-stage larvae

    International Nuclear Information System (INIS)

    The effect of gamma irradiation at doses of 40- and 50 kR on the development of third-stage larvae of Oesophagostomum columbianum and the protection conferred by these irradiated larvae against the nematode, was studied in 6-8 week old male Kashmir Merino lambs. At 40- and 50 kR doses, the third-stage larvae failed to develop to the adult stage in the intestine. Though single vaccination with 2000, 50 kR irradiated larvae failed to protect the animals against the infection, vaccination with the same number of 40 kR irradiated larvae conferred a partial protection. The presence of adult worms of O. columbianum in sites outside the intestine of 6-8 week old lambs have been demonstrated for the first time. (orig.)

  5. Comparative study of cultivation of feces in vermiculite or charcoal to obtain larvae of Strongyloides venezuelensis

    Directory of Open Access Journals (Sweden)

    Steveen Rios Ribeiro

    2014-10-01

    Full Text Available Introduction We compared feces culturing in charcoal or vermiculite to obtain Strongyloides venezuelensis larvae. Methods Feces (5g from infected rats was mixed with vermiculite (10g or coal (10g in plastic cups and incubated at 28°C for 48h. Larvae were recovered using Baermann-Moraes method. Results Significantly higher number of positive larval cultures were recovered from vermiculite than from charcoal (15/17 and 4/17, respectively; p < 0.001; 990.6 ± 307.5 and 215 ± 78.1 larvae, p = 0.027. Conclusions Vermiculite yields more larvae and provides cleaner pellets, improving larvae identification and facilitating their use for other purposes.

  6. Differences in vertical and horizontal distribution of fish larvae and zooplankton, related to hydrography

    DEFF Research Database (Denmark)

    Höffle, Hannes; Nash, Richard D.M.; Falkenhaug, Tone; Munk, Peter

    2013-01-01

    Planktonic fish larvae have little influence on their horizontal distribution, while they are able to control their vertical position in the water column. While prey and light are among the factors with an apparent influence on the vertical distribution, the effects of other factors are less clea...... conditions. Hence, larvae differed in their distributional patterns, but the relative depth distributions among the species in the larval community generally remained constant......Planktonic fish larvae have little influence on their horizontal distribution, while they are able to control their vertical position in the water column. While prey and light are among the factors with an apparent influence on the vertical distribution, the effects of other factors are less clear....... Notably, distributional differences between larvae of different fish species are poorly understood. Information on the horizontal distribution of larvae of 27 species and the vertical distribution of seven species of Gadidae, two Pleuronectidae and one Scophthalmidae, was compiled from one survey in the...

  7. Scanning electron microscope observations of brine shrimp larvae from space shuttle experiments

    Science.gov (United States)

    DeBell, L.; Paulsen, A.; Spooner, B.

    1992-01-01

    Brine shrimp are encysted as gastrula stage embryos, and may remain dehydrated and encysted for years without compromising their viability. This aspect of brine shrimp biology is desirable for studying development of animals during space shuttle flight, as cysts placed aboard a spacecraft may be rehydrated at the convenience of an astronaut, guaranteeing that subsequent brine shrimp development occurs only on orbit and not on the pad during launch delays. Brine shrimp cysts placed in 5 ml syringes were rehydrated with salt water and hatched during a 9 day space shuttle mission. Subsequent larvae developed to the 8th larval stage in the sealed syringes. We studied the morphogenesis of the brine shrimp larvae and found the larvae from the space shuttle experiments similar in rate of growth and extent of development, to larvae grown in sealed syringes on the ground. Extensive differentiation and development of embryos and larvae can occur in a microgravity environment.

  8. Seasonal fluctuation in the distribution of eggs and larvae of flat fishes (Pleuronectiformes - Pisces) in the Cochin Backwater

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    Attempts have been made to correlate the abundance of eggs and larvae of flat fishes belonging to families Cynoglossidae and Soleidae with the hydrographical parameters of the environment, particularly the salinity. The eggs and larvae were found...

  9. Impact of ultraviolet-B radiation on planktonic fish larvae: Alteration of the osmoregulatory function

    Energy Technology Data Exchange (ETDEWEB)

    Sucre, Elliott, E-mail: elliott.sucre@univ-montp2.fr [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Vidussi, Francesca [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Mostajir, Behzad [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Centre d' ecologie marine experimentale MEDIMEER (Mediterranean centre for Marine Ecosystem Experimental Research), Universite Montpellier 2-CNRS (UMS 3301), Station Mediterraneenne de l' Environnement Littoral, MEDIMEER, 2 Rue des Chantiers, 34200 Sete (France); Charmantier, Guy; Lorin-Nebel, Catherine [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France)

    2012-03-15

    Coastal marine ecosystems are submitted to variations of several abiotic and biotic parameters, some of them related to global change. Among them the ultraviolet-B (UV-B) radiation (UVBR: 280-320 nm) may strongly impact planktonic fish larvae. The consequences of an increase of UVBR on the osmoregulatory function of Dicentrarchus labrax larvae have been investigated in this study. In young larvae of D. labrax, as in other teleosts, osmoregulation depends on tegumentary ion transporting cells, or ionocytes, mainly located on the skin of the trunk and of the yolk sac. As early D. labrax larvae passively drift in the top water column, ionocytes are exposed to solar radiation. The effect of UVBR on larval osmoregulation in seawater was evaluated through nanoosmometric measurements of the blood osmolality after exposure to different UV-B treatments. A loss of osmoregulatory capability occured in larvae after 2 days of low (50 {mu}W cm{sup -2}: 4 h L/20 h D) and medium (80 {mu}W cm{sup -2}: 4 h L/20 h D) UVBR exposure. Compared to control larvae kept in the darkness, a significant increase in blood osmolality, abnormal behavior and high mortalities were detected in larvae exposed to UVBR from 2 days on. At the cellular level, an important decrease in abundance of tegumentary ionocytes and mucous cells was observed after 2 days of exposure to UVBR. In the ionocytes, two major osmoeffectors were immunolocalized, the Na{sup +}/K{sup +}-ATPase and the Na{sup +}/K{sup +}/2Cl{sup -} cotransporter. Compared to controls, the fluorescent immunostaining was lower in UVBR-exposed larvae. We hypothesize that the impaired osmoregulation in UVBR-exposed larvae originates from the lower number of tegumentary ionocytes and mucous cells. This alteration of the osmoregulatory function could negatively impact the survival of young larvae at the surface water exposed to UVBR.

  10. Impact of ultraviolet-B radiation on planktonic fish larvae: Alteration of the osmoregulatory function

    International Nuclear Information System (INIS)

    Coastal marine ecosystems are submitted to variations of several abiotic and biotic parameters, some of them related to global change. Among them the ultraviolet-B (UV-B) radiation (UVBR: 280–320 nm) may strongly impact planktonic fish larvae. The consequences of an increase of UVBR on the osmoregulatory function of Dicentrarchus labrax larvae have been investigated in this study. In young larvae of D. labrax, as in other teleosts, osmoregulation depends on tegumentary ion transporting cells, or ionocytes, mainly located on the skin of the trunk and of the yolk sac. As early D. labrax larvae passively drift in the top water column, ionocytes are exposed to solar radiation. The effect of UVBR on larval osmoregulation in seawater was evaluated through nanoosmometric measurements of the blood osmolality after exposure to different UV-B treatments. A loss of osmoregulatory capability occured in larvae after 2 days of low (50 μW cm−2: 4 h L/20 h D) and medium (80 μW cm−2: 4 h L/20 h D) UVBR exposure. Compared to control larvae kept in the darkness, a significant increase in blood osmolality, abnormal behavior and high mortalities were detected in larvae exposed to UVBR from 2 days on. At the cellular level, an important decrease in abundance of tegumentary ionocytes and mucous cells was observed after 2 days of exposure to UVBR. In the ionocytes, two major osmoeffectors were immunolocalized, the Na+/K+-ATPase and the Na+/K+/2Cl− cotransporter. Compared to controls, the fluorescent immunostaining was lower in UVBR-exposed larvae. We hypothesize that the impaired osmoregulation in UVBR-exposed larvae originates from the lower number of tegumentary ionocytes and mucous cells. This alteration of the osmoregulatory function could negatively impact the survival of young larvae at the surface water exposed to UVBR.

  11. Integrative neuromechanics of crawling in D. melanogaster larvae

    Science.gov (United States)

    Pehlevan, Cengiz; Paoletti, Paolo; Mahadevan, L

    2016-01-01

    Locomotion in an organism is a consequence of the coupled interaction between brain, body and environment. Motivated by qualitative observations and quantitative perturbations of crawling in Drosophila melanogaster larvae, we construct a minimal integrative mathematical model for its locomotion. Our model couples the excitation-inhibition circuits in the nervous system to force production in the muscles and body movement in a frictional environment, thence linking neural dynamics to body mechanics via sensory feedback in a heterogeneous environment. Our results explain the basic observed phenomenology of crawling with and without proprioception, and elucidate the stabilizing role that proprioception plays in producing a robust crawling phenotype in the presence of biological perturbations. More generally, our approach allows us to make testable predictions on the effect of changing body-environment interactions on crawling, and serves as a step in the development of hierarchical models linking cellular processes to behavior. DOI: http://dx.doi.org/10.7554/eLife.11031.001

  12. Eggs containing larvae of Enterobius vermicularis in vaginal smear

    Directory of Open Access Journals (Sweden)

    Jyothi B Shetty

    2012-01-01

    Full Text Available Enterobius vermicularis also known commonly as pinworm is the most common intestinal parasite. It is a nematode that inhabits the human terminal ileum, colon and appendix. The fertilized female migrates to the perianal area where eggs are deposited but occasionally introduces itself into adjacent orifices, most commonly the female genitourinary tract. Thus the eggs can be seen in the vaginal smear as a result of contamination. We report a case wherein the patient presented with signs and symptoms of vulvovaginitis. In her vaginal smear there were eggs of Enterobius vermicularis which showed a coiled larva within it. In the background there were plenty of acute inflammatory cells. This patient responded favorably to antihelminthics. We report this case to highlight the morphology of the parasite and also to emphasize that such findings should not be neglected. Timely reporting and appropriate treatment of such cases will prevent further complications of this parasite including endometritis, salphingitis and peritonitis.

  13. Cellular and genetic analysis of wound healing in Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Michael J Galko

    2004-08-01

    Full Text Available To establish a genetic system to study postembryonic wound healing, we characterized epidermal wound healing in Drosophila larvae. Following puncture wounding, larvae begin to bleed but within an hour a plug forms in the wound gap. Over the next couple of hours the outer part of the plug melanizes to form a scab, and epidermal cells surrounding the plug orient toward it and then fuse to form a syncytium. Subsequently, more-peripheral cells orient toward and fuse with the central syncytium. During this time, the Jun N-terminal kinase (JNK pathway is activated in a gradient emanating out from the wound, and the epidermal cells spread along or through the wound plug to reestablish a continuous epithelium and its basal lamina and apical cuticle lining. Inactivation of the JNK pathway inhibits epidermal spreading and reepithelialization but does not affect scab formation or other wound healing responses. Conversely, mutations that block scab formation, and a scabless wounding procedure, provide evidence that the scab stabilizes the wound site but is not required to initiate other wound responses. However, in the absence of a scab, the JNK pathway is hyperinduced, reepithelialization initiates but is not always completed, and a chronic wound ensues. The results demonstrate that the cellular responses of wound healing are under separate genetic control, and that the responses are coordinated by multiple signals emanating from the wound site, including a negative feedback signal between scab formation and the JNK pathway. Cell biological and molecular parallels to vertebrate wound healing lead us to speculate that wound healing is an ancient response that has diversified during evolution.

  14. Biochemistry and molecular biology of the Caenorhabditis elegans dauer larva

    International Nuclear Information System (INIS)

    Biochemical and molecular techniques have been used to study the formation and recovery of the developmentally arrested, non-feeding dauer stage of the nematode Caenorhabditis elegans. While investigating developmental transitions in energy metabolism, a major metabolite isolated from perchloric acid extracts has been identified as a modified uridine nucleotide. The compound was isolated by gel filtration and ion-exchange chromatography and its structure was determined by 1H NMR and 13C NMR spectroscopy. This compound is the most abundant metabolite detected in 31PMR spectra of perchloric acid extracts from growing larvae. In the absence of phosphoarginine or phosphocreatine, this modified nucleotide may have an important function in the nematode's energy metabolism, and it may also be found in several other invertebrates. During recovery from the dauer stage, metabolic activation is accompanied by a decrease in intracellular pH (pHi). Although metabolic activation has been associated with an alkaline pHi shift in other organisms, in vivo 31P NMR analysis of recovering dauer larvae shows a pHi decrease from ∼7.3 to ∼6.3 within 3 hr after the animals encounter food. This shift occurs before feeding begins, and coincides with, or soon follows, the development commitment to recover from the dauer stage, suggesting that control of pHi may be important in the regulation of larval development in nematodes. A library enriched for sequences expressed specifically during the L2d (predauer) stage was made by selecting plaques from a genomic lambda library that hybridized to subtracted L2d cDNA probes. Ultimately, three clones that were shown to hybridize only to L2d RNA were selected

  15. Composition of agarose substrate affects behavioral output of Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Anthi Aristomenis Apostolopoulou

    2014-01-01

    Full Text Available In the last decade the Drosophila larva has evolved into a simple model organism offering the opportunity to integrate molecular genetics with systems neuroscience. This led to a detailed understanding of the functional neuronal networks for a number of sensory functions and behaviors including olfaction, vision, gustation and learning and memory. Typically, behavioral assays in use exploit simple Petri dish setups with either agarose or agar as a substrate. However, neither the quality nor the concentration of the substrate is generally standardized across these experiments and there is no data available on how larval behavior is affected by such different substrates. Here, we have investigated the effects of different agarose concentrations on several larval behaviors. We demonstrate that agarose concentration is an important parameter, which affects all behaviors tested: preference, feeding, learning and locomotion. Larvae can discriminate between different agarose concentrations, they feed differently on them, they can learn to associate an agarose concentration with an odor stimulus and crawl faster on a substrate of higher agarose concentration. Additionally, we have investigated the effect of agarose concentration on three quinine based behaviors: preference, feeding and learning. We show that in all cases examined the behavioral output changes in an agarose concentration-dependent manner. Our results suggest that comparisons between experiments performed on substrates differing in agarose concentration should be done with caution. It should be taken into consideration that the agarose concentration can affect the behavioral output and thereby the experimental outcomes per se potentially due to an increased escape response on more rigid substrates.

  16. Description of the final instar larva of Orthetrum borneense Kimmins, 1936 (Odonata, Libellulidae), using rearing and molecular methods.

    Science.gov (United States)

    Steinhoff, Philip O M; Butler, Stephen G; Dow, Rory A

    2016-01-01

    The final instar larva of Orthetrum borneense Kimmins, 1936, is described and figured for the first time based on exuviae from three male and six female larvae collected in Sarawak, Borneo (East Malaysia). It is compared with an early instar larva, which was matched to the adult O. borneense by DNA barcoding, and the known larvae of other species of this genus that occur in the region. PMID:27394221

  17. Effect of stocking density on growth and survival of spotted sand bass Paralabrax maculatofasciatus larvae in a closed recirculating system

    OpenAIRE

    Álvarez González, Carlos; Ortiz Galindo, José Luis; Dumas, Silvie; Martínez Díaz, Sergio Francisco; Hernández Ceballos, Dora Esther; Grayeb del Alamo, Tanos; Moreno Lagorreta, Manuel; Peña Martínez, Renato; Civera Cerecedo, Roberto

    2001-01-01

    The effect on growth and survival of the initial stocking density (50, 100, 150, and 200 larvae/ L) in larval rearing of spotted sand bass was evaluated over 30 d in a closed recirculating system. Larvae were fed with rotifers, copepods, nauplii and adult Artemia, and spotted sand bass yolk-sac larvae. Water quality was monitored daily. The notochordal or standard length of sampled larvae was measured by image analysis. Specific growth rates at each density were compared by covariance analysi...

  18. 文竹(Asparagus plumosus Baker.)快速繁殖的初步研究%Primary study on fast propagation of Asparagus plumosus Baker.

    Institute of Scientific and Technical Information of China (English)

    吴均章; 万志刚

    2000-01-01

    文竹传统的繁殖方法主要为播种,结合分株.本文采用组织培养的方法,对文竹的快速繁殖进行初步的研究.结果发现不同的外植体材料,不同的培养基配方对文竹的生长都产生很大的影响.并初步建立了文竹的快繁体系.

  19. Dietary fatty acid composition affects food intake and gut-brain satiety signaling in Senegalese sole (Solea senegalensis, Kaup 1858) larvae and post-larvae.

    Science.gov (United States)

    Bonacic, Kruno; Campoverde, Cindy; Gómez-Arbonés, Javier; Gisbert, Enric; Estevez, Alicia; Morais, Sofia

    2016-03-01

    Little is known how dietary lipids affect food intake during larval development of fish, especially with regard to fatty acid (FA) composition. In fact, very little work has been done on appetite regulation and food intake in fish larvae in general, due to biological and technical difficulties associated with this type of studies. A new method using fluorescent microspheres as markers was developed in this study to evaluate food intake and prey selectivity of Senegalese sole larvae and post-larvae. Food intake was quantified in fish fed Artemia metanauplii enriched with oils differing in FA profile: cod liver oil (CLO), linseed oil (LSO), soybean oil (SBO) or olive oil (OO). The fish did not preferentially ingest a specific diet when presented with a choice. However, pre-metamorphic larvae from the CLO treatment ingested more metanauplii per g body weight, while differences in post-larvae were not significant. These findings were developed further by analyzing mRNA levels of a range of putative anorexigenic (pyya, pyyb, glp1, cckl, cart1a, cart1b, cart2a, cart4, pomca, pomcb, crf) and orexigenic (gal, npy, agrp2) genes, to identify those which are significantly affected by feeding and/or dietary FA composition. The variety of expression patterns observed highlighted the complexity of appetite regulatory mechanisms. In general, fish fed the CLO diet tended to show gene expression patterns most dissimilar to the remaining treatments. Expression in pre-metamorphic larvae was generally less in accordance with the putative function of the genes than in post-larvae, which could suggest a yet underdeveloped regulatory system. PMID:26851305

  20. Acceptability of irradiated larvae of the Mediterranean flour moth, Ephestia kuehniella, by a parasitoid, Venturia canescens

    International Nuclear Information System (INIS)

    Full text: The aim of releases of mass-produced natural enemies is to control a pest. In this context the aim of quality control should be to determine whether a natural enemy is still in a condition to properly control the pest. Formulated in this way we do not deal with terms like maximal or optimal quality, but something like acceptable quality. The aim of this study was to assess suitability and acceptability of irradiated host larvae of stored product moths by a parasitoid, Venturia canescens. Criteria for quality control were: (a) fertility of V. canescens adults emerged from irradiated moth larvae; (b) longevity of parasitoid adults emerged from irradiated moth larvae; and (c) weight (in mg) of parasitoid adults emerged from irradiated moth larvae, as compared to adults developed in nonirradiated host larvae. Adults of V. canescens emerged from moth larvae irradiated with a dose of 400 or 600 Gy were as fertile as the adults that emerged from untreated hosts (control). In all treatments, similar numbers of adults of the next generation were obtained. Also, the period of storage of irradiated and parasitised larvae of Ephestia kuehniella at low temperatures (5 Co) does not inhibit the development of parasitoids, and does not increase their mortality rates after the exposure to ambient temperature (25 deg. C). Finally, the fertility of emerged adults of V. canescens was not affected by the period of storage at lowered temperature. Longevity of V. canescens adults emerged from host larvae irradiated with a dose of 400 or 600 Gy was similar to that of the adults that emerged from untreated hosts (control). In all treatments, parasitoid adults were dead on day 13 after the emergence from host larvae. However, mortality rates of parasitoid adults emerged from non-irradiated larvae were somewhat lower than those developed in irradiated larvae. Weight of V. canescens adults emerged from moth larvae irradiated with a dose of 400 or 600 Gy of gamma radiation was very

  1. Large-scale expression of recombinant cardiac sodium-calcium exchange in insect larvae.

    Science.gov (United States)

    Hale, C C; Zimmerschied, J A; Bliler, S; Price, E M

    1999-02-01

    Recombinant bovine cardiac sodium-calcium exchange (NCX1) in a baculovirus construct was used to infect cabbage looper larvae (Trichoplusia ni). Infected larvae were homogenized and larvae membrane vesicles were purified. Western blot analysis indicated the presence of recombinant NCX1 protein in vesicles from infected larvae but not in controls. Vesicles from infected larvae expressed high levels of NCX1 activity (1.7 nmol Ca2+/mg protein/s) while vesicles from control larvae had no activity. NCX1 in larvae vesicles was bidirectional. Kinetic analysis yielded a Vmax of 3.6 nmol Ca2+/mg protein/s and a Km for Ca of 4.2 microM. NCX1 activity was inhibited by the exchange inhibitory peptide with an IC50 of 4 microM. These data demonstrate a novel and efficient method for the expression of large amounts of active recombinant NCX1 protein that has general application for expression and analysis of recombinant membrane proteins. PMID:10024479

  2. Distribution of Lepidopteran Larvae on Norway Spruce: Effects of Slope and Crown Aspect.

    Science.gov (United States)

    Kulfan, Ján; Dvořáčková, Katarína; Zach, Peter; Parák, Michal; Svitok, Marek

    2016-04-01

    Lepidoptera associated with Norway spruce, Picea abies (L.) Karsten, play important roles in ecosystem processes, acting as plant pests, prey for predators, and hosts for parasites and parasitoids. Their distribution patterns in spruce crowns and forests are only poorly understood. We examined how slope and crown aspect affect the occurrence and abundance of moth larvae on solitary spruce trees in a montane region in Central Europe. Moth larvae were collected from southern and northern crowns of trees growing on south- and north-facing slopes (four treatments) using emergence boxes at the end of winter and by the beating method during the growing season. Species responses to slope and crown aspect were not uniform. Treatment effects on moth larvae were stronger in the winter than during the growing season. In winter, the abundance of bud-boring larvae was significantly higher in northern than in southern crowns regardless of the slope aspect, while both slope and aspect had marginally significant effects on abundance of miners. During the growing season, the occurrence of free-living larvae was similar among treatments. Emergence boxes and beating spruce branches are complementary techniques providing valuable insights into the assemblage structure of moth larvae on Norway spruce. Due to the uneven distribution of larvae detected in this study, we recommend adoption of a protocol that explicitly includes sampling of trees from contrasting slopes and branches from contrasting crown aspect in all seasons. PMID:26795212

  3. Initial characterization of receptors for molecules that induce the settlement and metamorphosis of Haliotis rufescens larvae

    International Nuclear Information System (INIS)

    Larvae of the marine gastropod mollusc Haliotis refescens are induced to undergo metamorphosis by γ-aminobutyric acid (GABA) and stereochemically related compounds. The most potent of these inducers is (-)-β-(parachlorophenyl)-GABA (baclofen). The inductive response exhibits positive cooperatively, and is subject to both facilitation (up-regulation) and habituation (down-regulation). Facilitation is brought about by diamino acids such as L-diaminopropionic acid (L-DAPA), and is characterized by decreased Hill coefficients (n/sub H/) and concentration requirements (EC50) for inducers. Facilitation does not require the simultaneous presence of facilitating and inducing compounds, and the facilitated state is persistent. Larvae are capable of being up-regulated 2 days before they are capable of undergoing settlement and metamorphosis. Habituation can be brought about by exposure of pre-competent larvae to GABA 4 days prior to the attainment of competence; it is then slowly reversible. Larvae specifically bind tritiated (-)-baclofen in a manner that is saturable with both increasing time of exposure of larvae to, and with increasing concentration of, this compound. Specific binding can be competed for by unlabeled GABA-mimetic inducing molecules; the order of effectiveness of these molecules as competitors for specific binding correlates well with their effectiveness as inducers of metamorphosis. Facilitation of larvae by exposure to diamino acids does not alter their specific binding of tritiated (-)-baclofen. It is concluded from these findings that Haliotis larvae possess receptors for GABA-mimetic compounds

  4. Initial characterization of receptors for molecules that induce the settlement and metamorphosis of Haliotis rufescens larvae

    Energy Technology Data Exchange (ETDEWEB)

    Trapido-Rosenthal, H.G.

    1985-01-01

    Larvae of the marine gastropod mollusc Haliotis refescens are induced to undergo metamorphosis by ..gamma..-aminobutyric acid (GABA) and stereochemically related compounds. The most potent of these inducers is (-)-..beta..-(parachlorophenyl)-GABA (baclofen). The inductive response exhibits positive cooperatively, and is subject to both facilitation (up-regulation) and habituation (down-regulation). Facilitation is brought about by diamino acids such as L-diaminopropionic acid (L-DAPA), and is characterized by decreased Hill coefficients (n/sub H/) and concentration requirements (EC/sub 50/) for inducers. Facilitation does not require the simultaneous presence of facilitating and inducing compounds, and the facilitated state is persistent. Larvae are capable of being up-regulated 2 days before they are capable of undergoing settlement and metamorphosis. Habituation can be brought about by exposure of pre-competent larvae to GABA 4 days prior to the attainment of competence; it is then slowly reversible. Larvae specifically bind tritiated (-)-baclofen in a manner that is saturable with both increasing time of exposure of larvae to, and with increasing concentration of, this compound. Specific binding can be competed for by unlabeled GABA-mimetic inducing molecules; the order of effectiveness of these molecules as competitors for specific binding correlates well with their effectiveness as inducers of metamorphosis. Facilitation of larvae by exposure to diamino acids does not alter their specific binding of tritiated (-)-baclofen. It is concluded from these findings that Haliotis larvae possess receptors for GABA-mimetic compounds.

  5. Characterization of secreted proteases of Paenibacillus larvae, potential virulence factors involved in honeybee larval infection.

    Science.gov (United States)

    Antúnez, Karina; Anido, Matilde; Schlapp, Geraldine; Evans, Jay D; Zunino, Pablo

    2009-10-01

    Paenibacillus larvae is the causative agent of American Foulbrood (AFB), the most severe bacterial disease that affects honeybee larvae. AFB causes a significant decrease in the honeybee population affecting the beekeeping industry and agricultural production. After infection of larvae, P. larvae secretes proteases that could be involved in the pathogenicity. In the present article, we present the secretion of different proteases by P. larvae. Inhibition assays confirmed the presence of metalloproteases. Two different proteases patterns (PP1 and PP2) were identified in a collection of P. larvae isolates from different geographic origin. Forty nine percent of P. larvae isolates showed pattern PP1 while 51% exhibited pattern PP2. Most isolates belonging to genotype ERIC I - BOX A presented PP2, most isolates belonging to ERIC I - BOX C presented PP1 although relations were not significant. Isolates belonging to genotypes ERIC II and ERIC III presented PP2. No correlation was observed between the secreted proteases patterns and geographic distribution, since both patterns are widely distributed in Uruguay. According to exposure bioassays, isolates showing PP2 are more virulent than those showing PP1, suggesting that difference in pathogenicity could be related to the secretion of proteases. PMID:19638278

  6. Predation of Fruit Fly Larvae Anastrepha (Diptera: Tephritidae by Ants in Grove

    Directory of Open Access Journals (Sweden)

    W. D. Fernandes

    2012-01-01

    Full Text Available Based on evidence that ants are population regulatory agents, we examined their efficiency in predation of fruit fly larvae Anastrepha Schiner, 1868 (Diptera: Tephritidae. Hence, we considered the differences among species of fruit trees, the degree of soil compaction, and the content of soil moisture as variables that would explain predation by ants because these variables affect burying time of larvae. We carried out the experiment in an orchard containing various fruit bearing trees, of which the guava (Psidium guajava Linn., jaboticaba (Myrciaria jaboticaba (Vell. Berg., and mango trees (Mangifera indica Linn. were chosen for observations of Anastrepha. We offered live Anastrepha larvae on soil beneath the tree crowns. We observed for 10 min whether ants removed the larvae or the larvae buried themselves. Eight ant species were responsible for removing 1/4 of the larvae offered. The Pheidole Westwood, 1839 ants were the most efficient genus, removing 93% of the larvae. In compacted and dry soils, the rate of predation by ants was greater. Therefore, this study showed that ants, along with specific soil characteristics, may be important regulators of fruit fly populations and contribute to natural pest control in orchards.

  7. Inclusion of copepod Acartia tonsa nauplii in the feeding of Centropomus undecimalis larvae increases stress resistance

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    Wanessa de Melo-Costa

    2015-09-01

    Full Text Available This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1; A. tonsa nauplii (0.25 to 0.5 mL-1 and rotifers (5 to 7.5 mL-1, and A. tonsa nauplii (0.12 to 0.25 mL-1. The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively and resisted more heat stress (87.4% than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.

  8. Pathology of Yersinia entomophaga MH96 towards Costelytra zealandica (Coleoptera; Scarabaeidae) larvae.

    Science.gov (United States)

    Hurst, Mark Robin Holmes; van Koten, Chikako; Jackson, Trevor Anthony

    2014-01-01

    The bacterium Yersinia entomophaga was isolated from larvae of the New Zealand grass grub, Costelytra zealandica (Coleoptera: Scarabaeidae), found in soil. Following ingestion of a lethal dose of bacteria, larvae of C. zealandica reduced feeding activity and movement. After approximately 4h infected larvae convulsed and regurgitated dark digestive fluid and expelled frass pellets leaving the midgut empty and the larva amber in appearance. In the initial stages of infection, ingested bacteria were mostly contained within the peritrophic membrane and expelled with the gut fluid or transferred into the hind gut. While few Y. entomophaga were associated with the midgut epithelial cells, by 24h cells were swelling and bursting with vesicles being expelled into the midgut lumen. By 48h, bacteria had entered the haemocoel and the midgut cells had further deteriorated. After 72h, the cellular remnants were totally detached from the basal membrane the infected insects were filled with bacteria and moribund or dead with septicaemia. Mortality was directly proportional to dose and time after infection. By applying a range of doses, the LD50 was determined as 2.9×10(4)Y. entomophaga per C. zealandica larva, with an LT50 of 2.94days for doses of>1×10(5) per larva. Ingestion of low doses of bacteria did not inhibit feeding activity but led more slowly to death. By time of death, Y. entomophaga had multiplied, approximately 500 fold, in the cadavers of the infected larvae. PMID:24291403

  9. Behaviour of damselfly larvae (Enallagma cyathigerum) (Insecta, Odonata) after long-term exposure to PFOS

    Energy Technology Data Exchange (ETDEWEB)

    Gossum, Hans van [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: hans.vangossum@ua.ac.be; Bots, Jessica [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: jessica.bots@ua.ac.be; Snijkers, Tom [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: tom.snijkers@gmail.com; Meyer, Johan [Research group of Ecophysiology, Biochemistry and Toxicology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: izak.meyer@ua.ac.be; Van Wassenbergh, Sam [Laboratory for Functional Morphology, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp (Belgium)], E-mail: sam.vanwassenbergh@ua.ac.be; De Coen, Wim [Research group of Ecophysiology, Biochemistry and Toxicology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: wim.decoen@ua.ac.be; De Bruyn, Luc [Evolutionary Ecology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels (Belgium)], E-mail: luc.debruyn@ua.ac.be

    2009-04-15

    Perfluorooctane sulfonic acid (PFOS) is a persistent and ubiquitous environmental contaminant that has been detected in organisms worldwide. Here, we evaluate whether long-term (1 and 4 months) exposure to PFOS contamination affects the behavioural performance of freshwater larvae of the damselfly Enallagma cyathigerum (Insecta: Odonata). Our results show reduced behavioural performance with increasing PFOS concentration. In 1 month exposed larvae, no observed effect concentrations (NOECs) were 100 {mu}g/L for general activity. In 4 months exposed larvae, NOECs were 10 {mu}g/L, for each behavioural trait, except swimming acceleration of male larvae where the NOEC was 100 {mu}g/L. When faced with PFOS concentrations above the NOEC, E. cyathigerum larvae were less active, less capable to escape a simulated predator attack and less efficient in foraging. Together, our results show that damselfly larvae suffer reduced survival-related behavioural performance. - Long-term laboratory exposure to perfluorooctane sulfonic acid decreases behavioural performance of damselfly larvae (Insecta: Odonata)

  10. GC-MS investigation of the chemical composition of honeybee drone and queen larvae homogenate

    Directory of Open Access Journals (Sweden)

    Isidorov Valery A.

    2016-06-01

    Full Text Available Honeybee larva homogenate appears to be underrated and insufficiently explored but this homogenate is an exceptionally valuable honeybee product. Drone larva homogenate is very nutritional due to its high content of proteins, free amino acids, lipids, and carbohydrates. Moreover, the biological characteristics of honeybee larvae indicate the presence of chemical substances that may be pharmacologically active. In spite of the above, the chemical composition of honeybee larva has not gained as much attention as that of other bee products. In this study, the chemical composition of honeybee brood homogenate has been investigated using gas chromatography/mass spectrometry. As a result, it was possible to isolate as many as 115 extractive organic compounds from 6 samples of crude queen and 9 samples of drone homogenate. The main groups of substances extracted from either type of homogenate were composed of free amino acids and carbohydrates. The relative content of amino acids in queen homogenate as well as the share of essential amino acids were found to be higher than in the drone homogenate. Disaccharide trehalose was the dominant sugar in the queen larvae, whilst glucose prevailed in the drone larvae. Comparative chemical analyses of honeybee queen and drone larva homogenates have allowed us to make a preliminary inference about a higher overall value of the former.

  11. Resistance Detection of Aedes aegypti Larvae to Cypermethrin from Endemic Area in Cimahi City West Java

    Directory of Open Access Journals (Sweden)

    Endang Puji Astuti

    2014-06-01

    Full Text Available Vector control programs using chemical insecticide e.g organochlorin, organophosphate, carbamate, and pyrethroid (cypermethrin. When those insecticides were applied continuously, it may lead to vector resistance. The aim of this research was to detect any resistance of Ae. aegypti to cypermethrin in endemic areas of Cimahi. This research is a laboratory study that used biochemical test which referred to Lee’s method. Larva samples were collected from 8 villages, which are endemic area. Samples of larvae were collected from 15 villages belonged to dengue endemic areas in town of Cimahi, however, villages that meet the availability of larvae were only 8 villages. To detect the activity of monooxygenase enzyme, a biochemical assay was used in this research by created a reaction between larvae homogenate and sodium acetate substrate. The results of reaction were read using ELISA reader with spectrophotometer wave length of 595 nm. Overall, the results showed that most of the larvae in eight villages of Cimahi is still susceptible to cypermethrin. However, larvae from Cibabat village were 4% resistant, 2% tolerant, and 94% susceptible. On the other hand, Cigugur village showed that 12.7% larvae were tolerant and 87.3% still susceptible. Other villages like Cimahi, Cibeureum, Melong, Baros, Cipageran, and Pasirkaliki still remains susceptible. Resistance detection using biochemical assay of cypermethrin insecticide for Ae.aegypti resulting data stated that in 6 villages were still susceptible but in 3 other villages were already tolerant and 1 village was already resistance.

  12. Gut fluorescence analysis of barnacle larvae: An approach to quantify the ingested food

    Science.gov (United States)

    Gaonkar, Chetan A.; Anil, Arga Chandrashekar

    2012-10-01

    Gut fluorescence analysis can provide a snapshot of ingested food and has been employed in feeding studies of various organisms. In this study we standardised the gut fluorescence method using laboratory-reared barnacle larvae (Balanus amphitrite) fed with mono-algal diet Chaetoceros calcitrans, a unicellular diatom at a cell concentration of 2 × 105 cells ml-1. The gut fluorescence of IV-VI instar nauplii was found to be 370(±12) ng chlorophyll a larva-1 and in faecal pellets it was 224(±63) ng chlorophyll a larva-1. A phaeopigment concentration in larval gut was found to be 311(±13) ng larva-1 and in faecal pellets it was 172(±61) ng larva-1. The study also analysed larval samples collected from the field during different seasons from a tropical environment influenced by monsoons (Dona Paula bay, Goa, west coast of India), with characteristic temporal variations in phytoplankton abundance and diversity. Gut fluorescence of larvae obtained during the post-monsoon season was consistently higher when compared to the pre-monsoon season, suggesting the predominance of autotrophic forms in the larval gut during the post-monsoon season. Whereas, the low gut fluorescence obtained during the pre-monsoon season indicated the ingestion of food sources other than autotrophs. Such differences observed in the feeding behaviour of larvae could be due to differential availability of food for the larvae during different seasons and indicate the capability of larvae to feed on wide range of food sources. This study shows the value of the fluorescence method in feeding studies of planktotrophic organisms and in the evaluation of ecosystem dynamics.

  13. Feasibility study of biodiesel production using lipids of Hermetia illucens larva fed with organic waste.

    Science.gov (United States)

    Leong, Siew Yoong; Kutty, Shamsul Rahman Mohamed; Malakahmad, Amirhossein; Tan, Chew Khun

    2016-01-01

    Hermetia illucens larvae by nature are a decomposer which fed on organic wastes. This study explores the potential of producing biodiesel using lipids from H. illucens larvae. Three types of organic wastes (sewage sludge, fruit waste and palm decanter cake from oil palm mill) were selected based on considerable generation and disposal concern in the area of study as well as lack of investigations as feed for Hermetia illucens larvae in current literatures. Growth rate of the larvae was determined with studying the changes in the biomass per day. H. illucens larvae fed with fruit waste and palm decanter cake have shown growth rates of 0.52±0.02 and 0.23±0.09 g d(-1), respectively. No positive sign of growth were observed in the larvae fed with treated sewage sludge (-0.04±0.01 g d(-1)). Biodiesel as fatty acid methyl ester (FAME) was synthesized by transesterification of the larvae lipid using sulphuric acid as catalyst in methanol. FAME produced was ascertained using ATR-FTIR spectroscopy and GC-MS. The main compositions of fatty acid were found to be C12:0, C16:0 and C18:1n9c. Fatty acid composition of C12:0 fed with fruit waste, sewage sludge and palm decanter was found to be most abundant in the larvae lipid. The amount of C12:0 obtained was 76.13%, 58.31% and 48.06%, respectively. In addition, fatty acid of C16:0 was attained at 16.48% and 25.48% fed with sewage sludge and palm decanter, respectively. Based on the findings, FAME derived from larvae lipids is feasible to be used for biodiesel production. PMID:25872864

  14. Descrição da larva de último estádio de Micrathyria pseudeximia Westfall (Odonata, Libellulidae

    Directory of Open Access Journals (Sweden)

    Marina Schmidt Dalzochio

    2009-08-01

    Full Text Available A larva de último estádio de Micrathyria pseudeximia Westfall, 1992 é descrita e ilustrada a partir de material procedente de Cascavel, Paraná, Brasil. A caracterização do gênero com base nas larvas é ampliada.Description of the Ultimate Stadium Larva of Micrathyria pseudeximia Westfall(Odonata, Libellulidae.Abstract. The larva of ultimate stadium of Micrathyria pseudeximia Westfall, 1992 is described and illustrated based on material collected in Cascavel Municipality, Paraná State, Brazil. The generic concept based on the larvae is amplified.

  15. Trombiculidae larvae (Neotrombicula autumnalis) infestation in a Little Bittern (Ixobrychus minutus) in Turkey.

    Science.gov (United States)

    Cakiroglu, Duygu; Pekmezci, Didem; Meral, Yücel; Gokalp, Güvenç; Acici, Mustafa

    2008-04-01

    With this case report, we describe Trombiculidae larvae (Neotrombicula autumnalis) infestation in a Little Bittern (Ixobrychus minutus) which was brought to our clinics by the Directorship of Environmental and Forestry authorities of Samsun, Turkey in April, 2007. The male Little Bittern (I. minutus), with a black back and crown, and black wings with a large white patch on each wing, had thick Trombiculidae larvae infestation both on its legs. There were neither dermatological nor general conditional changes observed, except its superficial larval attachments to the skin. To our knowledge, this is the first report of Trombiculidae larvae (N. autumnalis) infestation in a Little Bittern (I. minutus) in Turkey. PMID:18266010

  16. Validation of otolith increment formation and the growth rate of fat greenling larvae

    OpenAIRE

    JOH, Mikimasa; Joh, Takashi; Matsu-ura, Teppei; Takatsu, Tetsuya

    2008-01-01

    We validated the daily formation 0f otolith increments of reared fat greenling Hexagrammos otakii larvae and examined the growth patterns of wild lavae. The mean notochord Length and otolith radius of newly hatched larvae were 8.31 mm and 273μm, respectively. Newly hatched larvae had some increments on their lapilli and a check was formed at hatching (hatch check). The relattonship between age and the number of increments formed outside the hatch chcck (NI)was linear regression (Nl=0.99Age-0....

  17. Jenis-jenis dan Kepadatan Larva Nyamuk di Kelurahan Gedung Johor, Kecamatan Medan Johor, Medan

    OpenAIRE

    Masy’ab, Nadiah

    2016-01-01

    Mosquitoes are living organisms in all around the world which is a disease vector for human . To know the area of mosquito’s spreading in one place, we need to do a larvae survey which measures the density of mosquito larvae in an area by observing directly into water reservoirs. This study aims to determine the type of species and the level of larvae density in Kelurahan Gedung Johor, Kecamatan Medan Johor, Medan. This is a descriptive study and collection of samples is don...

  18. INDEKS ENTOMOLOGI DAN KERENTANAN LARVA Aedes aegypti TERHADAP TEMEFOS DI KELURAHAN KARSAMENAK KECAMATAN KAWALU KOTA TASIKMALAYA

    Directory of Open Access Journals (Sweden)

    Hubullah Fuadzy

    2015-10-01

    Full Text Available AbstrakSalah satu upaya pengendalian vektor nyamuk Aedes aegypti adalah menggunakan larvasida sintetis seperti temefos. Pemanfaatan temefos secara terus menerus dan berulang merupakan faktor risiko terjadinya resistensi. Tujuan penelitian ini adalah untuk menentukan indeks entomologi dan status kerentanan larva Ae. aegypti terhadap temefos di Kelurahan Karsamenak Kecamatan Kawalu Kota Tasikmalaya. Jenis penelitian adalah eksperimen dengan rancangan acak lengkap. Populasi adalah larva nyamuk Ae. aegypti yang diperoleh dari 289 rumah penduduk di Kelurahan Karsamenak, dan sampel adalah 700 larva Ae. aegypti strain Karsamenak. Bioassay menggunakan metode Elliot dan Polson dengan konsentrasi diagnostik WHO sebesar 0,02 ppm. Hasil penelitian menunjukkan bahwa House Index (HI 24,9; Container Index (CI 9,05; Breteau Index (BI 29,07; dan Density Figure (DF 4. Larva Ae. aegypti umumnya ditemukan di Bak Mandi penduduk. Kemudian untuk membunuh 95% larva Ae. aegypti dibutuhkan konsentrasi temefos sebesar (LC95 0,02416 ppm (0,01917 ­ 0,03330 ppm dan RR95 3,02. Kelurahan Karsamenak termasuk wilayah yang potensial untuk penularan penyakit Demam Berdarah Dengue, dan larva Ae. aegypti terindikasi telah resisten terhadap temefos.Kata Kunci : Resisten, Aedes aegypti, temefos, kerentananAbstractOne effort for controlling Aedes aegypti as dengue vector is using synthetic larvacide such as temephos. Utilization of temephos continuously and repeatedly a risk factor for resistance. The objective of this study were to determine the entomology index and susceptibility of Ae. aegypti larvae against temephos in endemic areas of dengue fever in the Karsamenak District Kawalu of Tasikmalaya. The research was a true experimental study with a complete randomized design. The population were the larvae of Ae. aegypti were derived from 289 houses of resident in the Village Karsamenak and the sample was 700 larvae of Ae. aegypti strains Karsamenak. The Bioassay used Elliot and

  19. Jenis-Jenis Larva Nyamuk di Kelurahan Tanjung Rejo, Kecamatan Medan Sunggal, Medan

    OpenAIRE

    Woo, Xin Zhe

    2016-01-01

    Mosquitoe is a kind of animal that plays a role in transmitting various types of diseases. There are 4 stages of mosquito life cycle (egg-larva-pupa-adult) and the most effective prevention methode is from the larvae stage from mosquito because they have not been able to move freely and require water to survive. The present descriptive study was aimed to determine the types of mosquito larvae and what could promote the development of mosquito, thus mosquito control in Tanjung Rejo village, su...

  20. Influence of caffeine on sparing effect of dose fractionation in housefly larvae

    International Nuclear Information System (INIS)

    Caffeine, given during interfraction interval, abolishes the sparing effect of dose fractionation observed for delay of pupariation in Musca domestica larvae. When given as postirradiation treatment after single exposure, caffeine increases the delay in a synergistic manner. Pretreatment of the larvae with ascorbic acid for 3 h protects from radiation-induced delay whereas pretreatment with caffeine does not have any effect. Combination of ascorbic acid and caffeine pretreatment protects the larvae only at low concentration (0.05%) and not at high concentration (0.1%). (orig.)

  1. Metamorfosis del aparato digestivo de larvas carnívoras de Ceratophrys cranwelli (Anura: Leptodactylidae)

    OpenAIRE

    Ulloa Kreisel, Zandra E.

    2000-01-01

    Las larvas carnívoras de Ceratophrys cranwelli presentan un tubo digestivo más corto que la mayoría de las larvas de anuros, tiene 6 veces la longitud del cuerpo del renacuajo y se caracteriza también por tener un estómago larval. El presente trabajo tiene como objetivo el determinar el grado de transformaciones en la cavidad bucofaríngea y tubo digestivo en larvas de esta especie durante la metamorfosis y comparar las estructuras digestivas estudiadas en otras especies de Leptodactylidae de ...

  2. A case report of cutaneous larva migrans in a Mexican population of high marginalization

    Institute of Scientific and Technical Information of China (English)

    Isaac Aguirre Maldonadoa; Silvia Cruz Duartea; Felipe Gonzlez Velzqueza; Alfonso Alexander Aguilerab

    2014-01-01

    The creeping verminous dermatitis or cutaneous larva migrans is a parasitosis caused by percutaneous penetration and migration of larval nematode parasites characterized by producing one or more serpiginous erythematous, indurated, raised and pruritic lesion. The most common cause of cutaneous larva migrans is the Ancylostoma braziliense located in warm climate zones. In the present study, authors reported a case of cutaneous larva migrans with a characteristic clinical picture: erythematous-papular and vesicular lesion and serpiginous path, with progressive, and pruritic growth and it shown that a living area with immigration, tropical weather conditions and poverty may lead to this common infection.

  3. A case report of cutaneous larva migrans in a Mexican population of high marginalization

    Institute of Scientific and Technical Information of China (English)

    Isaac; Aguirre; Maldonadoa; Silvia; Cruz; Duartea; Felipe; Gonzlez; Velzqueza; Alfonso; Alexander; Aguilerab

    2014-01-01

    The creeping verminous dermatitis or cutaneous larva migrans is a parasitosis caused by percutaneous penetration and migration of larval nematode parasites characterized by producing one or more serpiginous erythematous,indurated,raised and pruritic lesion.The most common cause of cutaneous larva migrans is the Ancytostoma braziliensc located in warm climate zones.In the present study,authors reported a case of cutaneous larva migrans with a characteristic clinical picture:erythematous-papnlar and vesicular lesion and serpiginous path,with progressive,and pruritic growth and it shown that a living area with immigration,tropical weather conditions and poverty may lead to this common infection.

  4. The effect of BmNPV infection on protein metabolism in silkworm (Bombyx mori) larva

    OpenAIRE

    K Etebari; L Matindoost; SZ Mirhoseini; MW Turnbull

    2007-01-01

    Grasseri is one of the most important diseases of silkworm with significant yield loss, which is caused by nuclear polyhedrosis viruses (NPV). In the present research the effect of this disease on changes of biochemical compounds which are related to protein metabolism in 5th instar larvae were studied. The larvae that showed the grasseri symptoms after contamination with 5.5×10-4 polyhedral/ml were assumed as infected treatment. The hemolymph of infected and uninfected larvae in 3 and 5 days...

  5. Interespecific competition between Peckia chrysostoma and Adiscochaeta ingens (Diptera: Sarcophagidae) larvae reared in laboratory

    OpenAIRE

    Marisa Vianna Ferraz

    1993-01-01

    Groups of 10 and 20 first instar larvae of Peckia chrysostoma (Wiedemann, 1830) were combined in a proteic source media with groups of the same number of first instar larvae of Adiscochaeta ingens (Walker, 1849) under the environmental conditions of Rio de Janeiro, RJ, Brasil. P. chrysostoma and A. ingens obtained average competitive potentials of 94.0 ± 2.0% and 31.0 ± 5.0% respectively. In the second experiment, larvae of P. chrysostoma were introduced approximately 15 hr after the introduc...

  6. Annotated records of scombroid eggs and larvae distribution in northeastern Mediterranean waters

    Directory of Open Access Journals (Sweden)

    V. VASSILOPOULOU

    2012-12-01

    Full Text Available The distribution of eggs and larvae of scombroid fish in northeastern Greek waters were studied during the summer of three consecutive years(1992-1994 to determine spawning, time of spawning peaks, and the possible preferred spawning grounds. Among eggs only those of Xiphias gladius were successfully identified. Larvae of Thunnus alalunga, Euthynnus alleteratus, X. gladius and Auxis rochei were recorded, the latter species being encountered more frequently than the rest. Most scombroid larvae were collected in the Sporades Islands’ basin and their abundance, particularly that of A. rochei, was relatively increased at the end of the summer, possibly suggesting increased spawning activities during that period.

  7. Identification of entomopathogenic Bacillus isolated from Simulium (Diptera, Simuliidae larvae and adults

    Directory of Open Access Journals (Sweden)

    Cavados CFG

    2001-01-01

    Full Text Available Entomopathogenic bacteria isolated from Simulium larvae and adults from breeding sites in the states of São Paulo and Rio de Janeiro, Brazil, were identified as 18 strains of Bacillus thuringiensis and one of B. sphaericus. Most of these strains were serotyped according to their flagellar antigens. However, nine of the B. thuringiensis samples, could not be serotyped and were designated as "autoagglutinating"; they were also shown to be toxic in preliminary tests against Aedes aegypti larvae. Additionally, B. sphaericus was also shown to be toxic towards Culex quinquefasciatus larvae.

  8. Habitat stability and occurrences of malaria vector larvae in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Atieli Harrysone

    2009-10-01

    Full Text Available Abstract Background Although the occurrence of malaria vector larvae in the valleys of western Kenya highlands is well documented, knowledge of larval habitats in the uphill sites is lacking. Given that most inhabitants of the highlands actually dwell in the uphill regions, it is important to develop understanding of mosquito breeding habitat stability in these sites in order to determine their potential for larval control. Methods A total of 128 potential larval habitats were identified in hilltops and along the seasonal streams in the Sigalagala area of Kakamega district, western Kenya. Water availability in the habitats was followed up daily from August 3, 2006 to February 23, 2007. A habitat is defined as stable when it remains aquatic continuously for at least 12 d. Mosquito larvae were observed weekly. Frequencies of aquatic, stable and larvae positive habitats were compared between the hilltop and seasonal stream area using χ2-test. Factors affecting the presence/absence of Anopheles gambiae larvae in the highlands were determined using multiple logistic regression analysis. Results Topography significantly affected habitat availability and stability. The occurrence of aquatic habitats in the hilltop was more sporadic than in the stream area. The percentage of habitat occurrences that were classified as stable during the rainy season is 48.76% and 80.79% respectively for the hilltop and stream area. Corresponding frequencies of larvae positive habitats were 0% in the hilltop and 5.91% in the stream area. After the rainy season, only 23.42% of habitat occurrences were stable and 0.01% larvae positive habitats were found in the hilltops, whereas 89.75% of occurrences remained stable in the stream area resulting in a frequency of 12.21% larvae positive habitats. The logistic regression analysis confirmed the association between habitat stability and larval occurrence and indicated that habitat surface area was negatively affecting the

  9. Metabolomic Analysis of Diapausing and Noni-diapausing Larvae of the European Corn Borer Ostrinia nubilalis (Hbn.) (Lepidoptera: Crambidae).

    Science.gov (United States)

    Purać, Jelena; Kojić, Danijela; Popović, Željko D; Vukašinović, Elvira; Tiziani, Stefano; Günther, Ulrich L; Grubor-Lajšić, Gordana

    2015-01-01

    In this study, an (1)H-NMR -based metabolomic approach was used to investigate the biochemical mechanisms of diapause and cold hardiness in diapausing larvae of the European corn borer Ostrinia nubilalis. Metabolomic patterns in polar hemolymph extracts from non-diapausing and diapausing larvae of O. nubilalis were compared. Analysis indicated 13 metabolites: 7 amino acids, glycerol, acetate, citrate, succinate, lactate and putrescine. Results show that diapausing larvae display different metabolomic patterns compared to active non-diapausing larvae, with predominant metabolites identified as glycerol, proline and alanine. In specific diapausing larvae initially kept at 5 °C then gradually chilled to –3 °C and –16 °C, alanine , glycerol and acetate were predominant metabolites. (1)H-NMR spectroscopy provides new insight into the metabolomic patterns associated with cold resistance and diapause in O. nubilalis larvae, suggesting distinct metabolomes function in actively developing and diapausing larvae. PMID:26680702

  10. Xenobiotics Produce Distinct Metabolomic Responses in Zebrafish Larvae (Danio rerio).

    Science.gov (United States)

    Huang, Susie S Y; Benskin, Jonathan P; Chandramouli, Bharat; Butler, Heather; Helbing, Caren C; Cosgrove, John R

    2016-06-21

    Sensitive and quantitative protocols for characterizing low-dose effects are needed to meet the demands of 21st century chemical hazard assessment. To test the hypothesis that xenobiotic exposure at environmentally relevant concentrations produces specific biochemical fingerprints in organisms, metabolomic perturbations in zebrafish (Danio rerio) embryo/larvae were measured following 24 h exposures to 13 individual chemicals covering a wide range of contaminant classes. Measured metabolites (208 in total) included amino acids, biogenic amines, fatty acids, bile acids, sugars, and lipids. The 96-120 h post-fertilization developmental stage was the most appropriate model for detecting xenobiotic-induced metabolomic perturbations. Metabolomic fingerprints were largely chemical- and dose-specific and were reproducible in multiple exposures over a 16-month period. Furthermore, chemical-specific responses were detected in the presence of an effluent matrix; importantly, in the absence of morphological response. In addition to improving sensitivity for detecting biological responses to low-level xenobiotic exposures, these data can aid the classification of novel contaminants based on the similarity of metabolomic responses to well-characterized "model" compounds. This approach is clearly of use for rapid, sensitive, and specific analyses of chemical effect on organisms, and can supplement existing methods, such as the Zebrafish Embryo Toxicity assay (OECD TG236), with molecular-level information. PMID:27232715

  11. Parasitic infection protects wasp larvae against a bacterial challenge.

    Science.gov (United States)

    Manfredini, Fabio; Beani, Laura; Taormina, Mauro; Vannini, Laura

    2010-09-01

    Host antibacterial defense after Strepsiptera parasitization is a complex and rather unexplored topic. The way how these parasites interact with bacteria invading into the host insect during an infection is completely unknown. In the present study we demonstrate that larvae of the paper wasp Polistes dominulus are more efficient at eliminating bacteria when they are parasitized by the strepsipteran insect Xenos vesparum. We looked at the expression levels of the antimicrobial peptide defensin and we screened for the activity of other hemolymph components by using a zone of inhibition assay. Transcription of defensin is triggered by parasitization, but also by mechanical injury (aseptic injection). Inhibitory activity in vitro against the Gram positive bacterium Staphylococcus aureus is not influenced by the presence of the parasite in the wasp or by a previous immune challenge, suggesting a constitutive power of killing this bacterium by wasp hemolymph. Our results suggest either direct involvement of the parasite or that defensin and further immune components not investigated in this paper, for example other antimicrobial peptides, could play a role in fighting off bacterial infections in Polistes. PMID:20546915

  12. Seasonal variation of vitamin and sterol content of chironomidae larvae.

    Science.gov (United States)

    Kara, Tuba

    2013-11-15

    In the present study, seasonal variation of vitamin and sterol content of Chironomidae larvae were determined by using HPLC. As the result of vitamin analysis, we found alpha-tocopherol, retinol, K1, K2, D2 and D3. When the seasonal variation of vitamin groups were compared, a significant increase was observed in vitamin K1, K2, D2 and alpha-tocopherol in all seasons. A significant increase was observed in vitamin D3 in spring. And also vitamin A level high in autumn and winter, alpha-tocopherol level was significantly high among vitamins. When vitamin groups were compared statistically, differences were detected between seasons (p < 0.001). Analyzing the content of sterol, we found ergosterol, cholesterol, stigmasterol and beta-sitosterol in all seasons. Cholesterol level was found to be significantly high in sterols. When sterol contents were compared statistically, differences were detected between seasons (p < 0.001). In conclusion, the reasons for these differences are larval development feature and the variety of food in different seasons. PMID:24511704

  13. Chronic Wounds, Biofilms and Use of Medicinal Larvae

    Directory of Open Access Journals (Sweden)

    Linda J. Cowan

    2013-01-01

    Full Text Available Chronic wounds are a significant health problem in the United States, with annual associated costs exceeding $20 billion annually. Traditional wound care consists of surgical debridement, manual irrigation, moisture retentive dressings, and topical and/or systemic antimicrobial therapy. However, despite progress in the science of wound healing, the prevalence and incidence of chronic wounds and their complications are escalating. The presence & complexity of bacterial biofilms in chronic wounds has recently been recognized as a key aspect of non-healing wounds. Bacterial biofilms are sessile colonies of polymicrobial organisms (bacteria, fungus, etc. enclosed within a self-produced exopolymeric matrix that provides high levels of tolerance to host defenses, antibiotics and antiseptics. Thus, there is a need for alternative therapies to reduce biofilms in chronic wounds. In this report, we present initial findings from in vitro experiments which show that larval debridement therapy with disinfected blow fly larvae (Phaenicia sericata reduced total CFUs (6-logs of planktonic and mature biofilms of Pseudomonas aeruginosa or Staphylococcus aureus grown on dermal pig skin explants by 5-logs after 24 hours of exposure, and eliminated biofilms (no measurable CFUs after 48 hours of exposure.

  14. Enzymatic properties of phenoloxidase from Pieris rapae (Lepidoptera) larvae

    Institute of Scientific and Technical Information of China (English)

    CHAO-BIN XUE; WAN-CHUN LUO; QING-XI CHEN; QIN WANG; LI-NA KE

    2006-01-01

    The kinetic parameters of partially purified phenoloxidase (PO, EC. 1.14.18.1) from the 5th instar larvae of Pieris rapae (Lepidoptera) were determined, using L-3, 4-dihydroxyphenylalanine (L-DOPA) as substrate. The optimal pH and temperature of the enzyme for the oxidation of L-DOPA were determined to be at pH 7.0 and at 42℃,respectively. The enzyme was stable between pH 6.5 and 7.4 and at temperatures lower than 37℃. At pH 6.8 and 37℃, the Michaelis constant (Km) and maximal velocity (Vm) of the enzyme for the oxidation of L-DOPA were determined to be 0.80 mmol/L and 1.84 μmol/ L/min, respectively. Tetra-hexylresorcinol and 4-dodecylresorcinol effectively inhibited activity of phenoloxidase and this inhibition was reversible and competitive, with the IC50 of 1.50 and 1.12μmol/L, respectively. The inhibition constants were estimated to be 0.50 and 0.47μmol/L, respectively.

  15. Effect of Irradiation on Anisakis Larvae in Salted Herring

    International Nuclear Information System (INIS)

    The authors describe experiments to test the practicability of using irradiation to kill Anisakis marina larvae in lightly salted herring (Clupea harengus), The lower salt concentration used since the second world war for the preservation of gibbed herring is insufficient to kill the parasites that may be harmful to the consumer. The nematodes were subjected to irradiation, either in water or saline suspension, or pressed between salted herring fillets or in situ in salted gibbed herring. The results were disappointing. In aqueous suspensions, a salt concentration of 6% and a dose of 1.0 Mrad resulted in 100% kill, but appreciable numbers survived (although many of these were inactive) at lower irradiation dosages and at lower salt concentrations. It was noted that for doses of either 0 or 0.3 Mrad the highest proportion of survivals occurred in 3% salt solutions. In testing the effect of irradiation on parasites in the fish or placed between fillets the dosages were limited, because of flavour and colour changes, to 0.3 Mrad for salted ripened herring, and 0.6 Mrad for 5-day-old lightly salted herring. Substantial numbers of nematodes survived these doses. (author)

  16. MRI findings of spinal visceral larva migrans of Toxocara canis

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study is to investigate the MRI findings of visceral larva migrans (VLS) of Toxocara canis in spinal cord. Materials and methods: We retrospectively reviewed spinal MRI findings in eight patients with serologically proven Toxocara canis between 2005 and 2008. We evaluated the location, length, extent and migration of the lesion, MR signal intensity (SI), enhancement pattern, and swelling of the spinal cord. We evaluated clinical features including presenting symptoms and signs and treatment response. Results: Total 8 patients (M = 8; age range 36-79 years) were included. The lesions were located in the cervical or thoracic spinal cord in all patients. All lesions showed high SI and minimal or mild swelling of involved spinal cord on T2WI and focal nodular enhancement on posterior or posterolateral segment of spinal cord. The length of involved lesion was relatively short in most patients. There was a migration of lesion in one patient. In spite of albendazole or steroid treatment, neurological symptoms or signs were not significantly improved in all patients. Conclusion: Although all lesions show non-specific imaging findings like non-tumorous myelopathy mimicking transverse myelitis, single lesion, focal nodular enhancement on posterior or posterolateral segment of spinal cord, relatively short segmental involvement and migration of lesion may be characteristic findings of spinal VLM of Toxocara canis. In addition, the reluctant response to the treatment may be characteristic of spinal VLM of Toxocara canis.

  17. MRI findings of spinal visceral larva migrans of Toxocara canis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Ho, E-mail: leeinho1974@hanmail.ne [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Department of Radiology, Chungnam National University Hospital, 33 Munhwa-ro, Jung-gu, Daejeon 301-721 (Korea, Republic of); Kim, Sung Tae, E-mail: st7.kim@hotmail.co [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Oh, Dae Kun, E-mail: odk6464@nate.co [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Kim, Hyung-Jin, E-mail: hyungkim@skku.ed [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Kim, Keon Ha, E-mail: somatom@skku.ed [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Jeon, Pyoung, E-mail: drpjeon@gmail.co [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of); Byun, Hong Sik, E-mail: byun5474@skku.ed [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-Gu, Seoul 135-710 (Korea, Republic of)

    2010-08-15

    Purpose: The purpose of this study is to investigate the MRI findings of visceral larva migrans (VLS) of Toxocara canis in spinal cord. Materials and methods: We retrospectively reviewed spinal MRI findings in eight patients with serologically proven Toxocara canis between 2005 and 2008. We evaluated the location, length, extent and migration of the lesion, MR signal intensity (SI), enhancement pattern, and swelling of the spinal cord. We evaluated clinical features including presenting symptoms and signs and treatment response. Results: Total 8 patients (M = 8; age range 36-79 years) were included. The lesions were located in the cervical or thoracic spinal cord in all patients. All lesions showed high SI and minimal or mild swelling of involved spinal cord on T2WI and focal nodular enhancement on posterior or posterolateral segment of spinal cord. The length of involved lesion was relatively short in most patients. There was a migration of lesion in one patient. In spite of albendazole or steroid treatment, neurological symptoms or signs were not significantly improved in all patients. Conclusion: Although all lesions show non-specific imaging findings like non-tumorous myelopathy mimicking transverse myelitis, single lesion, focal nodular enhancement on posterior or posterolateral segment of spinal cord, relatively short segmental involvement and migration of lesion may be characteristic findings of spinal VLM of Toxocara canis. In addition, the reluctant response to the treatment may be characteristic of spinal VLM of Toxocara canis.

  18. Capture of white sturgeon larvae downstream of The Dalles Dam, Columbia River, Oregon and Washington, 2012

    Science.gov (United States)

    Parsley, Michael J.; Kofoot, Eric

    2013-01-01

    Wild-spawned white sturgeon (Acipenser transmontanus) larvae captured and reared in aquaculture facilities and subsequently released, are increasingly being used in sturgeon restoration programs in the Columbia River Basin. A reconnaissance study was conducted to determine where to deploy nets to capture white sturgeon larvae downstream of a known white sturgeon spawning area. As a result of the study, 103 white sturgeon larvae and 5 newly hatched free-swimming embryos were captured at 3 of 5 reconnaissance netting sites. The netting, conducted downstream of The Dalles Dam on the Columbia River during June 25–29, 2012, provided information for potentially implementing full-scale collection efforts of large numbers of larvae for rearing in aquaculture facilities and for subsequent release at a larger size in white sturgeon restoration programs.

  19. Toxic effects of coastal and marine plant extracts on mosquito larvae

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Solimabi; DeSouza, L.; Kamat, S.Y.

    (Halophila ovalis, Syringodium isoetifolium), and a lichen (Umbilicaria aprine) were studied for their toxicity against larvae of the mosquito Culex quinquefasciatus. Petroleum-ether fractions (PE) were more effective than chloroform fractions (C) in all...

  20. Viviparity of larvae, a new type of development in phoronids (Lophophorata: Phoronida).

    Science.gov (United States)

    Temereva, E N; Malakhov, V V

    2016-03-01

    A new type of phoronid development, viviparity of larvae, has been discovered in a new phoronid species that lives as a commensal of digging sand shrimps in Vostok Bay, the Sea of Japan. The embryos develop in the mother's trunk coelom up to the young larva stage. During development, embryos increase in size twice and probably obtain nutriment from the mother's coelomic fluid. Spawning occurs by young larvae, which are released through nephridiopores. The new type of development is described in a phoronid that has a small body size but a high fertility, producing large amounts of extremely small eggs. The combination of viviparity and large number of eggs increases the number of competent larvae that can undergo metamorphosis in the burrows of shrimps. PMID:27193880

  1. Vertical and horizontal transmission of tilapia larvae encephalitis virus: the bad and the ugly.

    Science.gov (United States)

    Sinyakov, Michael S; Belotsky, Sandro; Shlapobersky, Mark; Avtalion, Ramy R

    2011-02-01

    Impairment of innate immunity in tilapia larvae after vertical and horizontal infection with the newly characterized tilapia larvae encephalitis virus (TLEV) was accessed by evaluation of cell-mediated reactive oxygen species (ROS) production in affected fish with the use of horseradish peroxidase-amplified luminol-dependent chemiluminescence assay. The priming in-vivo infection with TLEV resulted in downregulation of ROS response in both vertically- and horizontally-infected fish; this suppression was further exacerbated by specific in-vitro booster infection with the same virus. Application of Ca ionophore and phorbol myristate acetate as alternative nonspecific boosters enabled restoration of ROS release in vertically-infected but not in horizontally-infected larvae. The results indicate severe TLEV-imposed phagocyte dysfunction in affected larvae. The difference in restoration potential of ROS production after vertical and horizontal virus transmission is interpreted in the frame of principal distinctions between the two modes. PMID:21131016

  2. Effect of Exogenous MJA Treatment of Tea Plants on the Growth of Geometrid Larvae

    Institute of Scientific and Technical Information of China (English)

    GUI Lian-you; CHEN Zong-mao; LIU Shu-sheng

    2005-01-01

    The effect of tea plant Camellia sinensis induced by exogenous methyl jasmonate (MJA) on lipoxygenase (LOX), polyphenol oxidase (PPO) and proteinase inhibitor (PI) activity in the leaves of tea plants, as well as the growth and midgut proteinase activity of the geometrid Ectropis obliqua larvae were studied. MJA significantly induced LOX, PPO and PI activity in leaves of tea plants. When geometrid larvae have fed on leaves of tea plants treated with MJA, the activities of the high alkaline trypsin-like enzyme and chymotrypsin-like enzyme in their midgut were significantly inhibited, but the activities of the low alkaline trypsin-like enzyme in their midgut were unaffected, leading to imbalance between different types of proteinase activity in the midgut of the larvae and in turn, the growth were inhibited. These chains of response may be an important mechanism of the direct resistance induced by MJA-treatment of tea plant on geometrid larvae.

  3. Quantification of the energy required for the destruction of Balanus Amphitrite larva by ultrasonic treatment

    Digital Repository Service at National Institute of Oceanography (India)

    Seth, N.; Chakravarty, P.; Khandeparker, L.; Anil, A.C.; Pandit, A.B.

    organism. Since the power used and treatment time for disinfection are economically, and practically, the most important parameters, the energy required to pulverize the larvae into pieces less than equal to 30 mm was determined as a function...

  4. Expanding the locomotion repertoire of the eigenfish: Study of wildtype zebrafish larva escape response

    Science.gov (United States)

    Benitez-Jones, Maria; Girdhar, Kiran; Chemla, Yann; Gruebele, Martin

    2014-03-01

    The zebrafish larva is a thoroughly studied and an extensively used model for behavioral and biomedical research. The Zebrafish Laboratory at the University of Illinois at Urbana-Champaign has applied a mathematical method to describe quantitatively the larva's swimming behavior. With this method, the 98% of the larva's free-swimming behavior is described by its simplifiedeigen-fish model, which is a linear combination of its three characteristic components, or three eigen-modes. This presentation focuses on the quantification of a different swimming behavior called escape response in wildtype (WT) zebrafish larvae. Although more data is required before assuming certainty in our results, the escape response of the WT was also described up to 98% by three eigen-modes. This REU program is supported by NSF Grant PHY-1062690.

  5. Organochlorine chemical hazards for sturgeon larvae in the Middle Mississippi River National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We conducted an ecological risk assessment to characterize organochlorine chemical hazards for sturgeon larvae in the Middle Mississippi River National Wildlife...

  6. 16S rRNA amplicon sequencing dataset for conventionalized and conventionally raised zebrafish larvae.

    Science.gov (United States)

    Davis, Daniel J; Bryda, Elizabeth C; Gillespie, Catherine H; Ericsson, Aaron C

    2016-09-01

    Data presented here contains metagenomic analysis regarding the sequential conventionalization of germ-free zebrafish embryos. Zebrafish embryos that underwent a germ-free sterilization process immediately after fertilization were promptly exposed to and raised to larval stage in conventional fish water. At 6 days postfertilization (dpf), these "conventionalized" larvae were compared to zebrafish larvae that were raised in conventional fish water never undergoing the initial sterilization process. Bacterial 16S rRNA amplicon sequencing was performed on DNA isolated from homogenates of the larvae revealing distinct microbiota variations between the two groups. The dataset described here is also related to the research article entitled "Microbial modulation of behavior and stress responses in zebrafish larvae" (Davis et al., 2016) [1]. PMID:27508247

  7. Identification of Balanus amphitrite larvae from field zooplankton using species-specific primers

    Digital Repository Service at National Institute of Oceanography (India)

    Gaonkar, C.C.; Khandeparker, L.; Desai, D.V.; Anil, A.C.

    Identification of marine invertebrate larvae using morphological characters is laborious and complicated by phenotypic plasticity. Balanus amphitrite is a dominant barnacle, important in the context of intertidal ecology and biofouling of manmade...

  8. Identification of Nanopillars on the Cuticle of the Aquatic Larvae of the Drone Fly (Diptera: Syrphidae).

    Science.gov (United States)

    Hayes, Matthew J; Levine, Timothy P; Wilson, Roger H

    2016-01-01

    Here, we describe a nano-scale surface structure on the rat-tailed maggot, the aquatic larva of the Drone fly Eristalis tenax(L.). Larvae of this syrphid hover fly live in stagnant, anaerobic water-courses that are rich in organic matter. The larvae burrow into fetid slurry and feed on microorganisms which they filter out from the organic material. This environment is rich in bacteria, fungi and algae with the capacity to form biofilms that might develop on the larval surface and harm them. Using transmission and scanning electron microscopy we have identified an array of slender (typically < 100 nm in diameter) nanopillars that cover the surface of the larvae. The high density and dimensions of these spine-like projections appear to make it difficult for bacteria to colonize the surface of the animal. This may interfere with the formation of biofilms and potentially act as a defence against bacterial infection. PMID:27030395

  9. Drosophila melanogaster larvae control amylase secretion according to the hardness of food.

    Science.gov (United States)

    Sakaguchi, Honami; Suzuki, Masataka G

    2013-01-01

    Drosophila melanogaster larvae excrete amylase and perform external digestion of their food. In this study, to investigate whether their external digestion ability varies in response to changes in the external environment, we measured the relative amount of amylase excreted by larvae using a new method: the iodine starch agar method (ISAM). Analysis using this method revealed that the amount of amylase excreted by larvae increased in accordance with the increase in the agar concentration. In addition, we investigated the effect on the larval growth rate of adding amylase to the diet. Pupation occurred 24 h later in food containing 1% amylase than in food containing no amylase. These results suggest that the larvae adjust their amylase excretion in response to changes in the external environment, and that its level has a marked influence on the larval growth rate. PMID:23964241

  10. Drosophila melanogaster larvae control amylase secretion according to the hardness of food

    Directory of Open Access Journals (Sweden)

    HonamiSakaguchi

    2013-08-01

    Full Text Available Drosophila melanogaster larvae excrete amylase and perform external digestion of their food. In this study, to investigate whether their external digestion ability varies in response to changes in the external environment, we measured the relative amount of amylase excreted by larvae using a new method: the iodine starch agar method (ISAM. Analysis using this method revealed that the amount of amylase excreted by larvae increased in accordance with the increase in the agar concentration. In addition, we investigated the effect on the larval growth rate of adding amylase to the diet. Pupation occurred 24 h later in food containing 1% amylase than in food containing no amylase. These results suggest that the larvae adjust their amylase excretion in response to changes in the external environment, and that its level has a marked influence on the larval growth rate.

  11. Dynamic of decapod crustacean larvae on the entrance of Guanabara bay

    Directory of Open Access Journals (Sweden)

    Fernandes Lohengrin Dias de Almeida

    2002-01-01

    Full Text Available In the present study, we observed seasonal variations in the density of decapod larvae as well as changes in density related to diurnal and tidal cycles. Among the decapod larvae collected, portunids and grapsids were the most abundant, especially during nocturnal ebb tides and near the surface. The same results were obtained in late winter (September and late summer (March. These results demonstrated a flow of decapod larvae from Guanabara Bay to adjacent coastal waters. Luciferid (Lucifer faxoni was the only group with high densities during flood tides and we suggest this is an evidence of L. faxoni larvae entering Guanabara Bay in late winter. Probably these changes in distribution of Lucifer faxoni among winter and summer were related to reproductive cycle in the bay. For the portunids, grapsids and ocypodids, a similar dispersion strategy was observed towards adjacent coastal waters in the surface during nocturnal ebb tides.

  12. The effect of BmNPV infection on protein metabolism in silkworm (Bombyx mori larva

    Directory of Open Access Journals (Sweden)

    K Etebari

    2007-02-01

    Full Text Available Grasseri is one of the most important diseases of silkworm with significant yield loss, which is caused by nuclear polyhedrosis viruses (NPV. In the present research the effect of this disease on changes of biochemical compounds which are related to protein metabolism in 5th instar larvae were studied. The larvae that showed the grasseri symptoms after contamination with 5.5×10-4 polyhedral/ml were assumed as infected treatment. The hemolymph of infected and uninfected larvae in 3 and 5 days after 4th molting were collected and its total protein, urea, alanine aminotransferase (ALT and aspartate aminotransferase (AST were measured. The results showed that the amount of all the compounds except urea were considerably different in both groups. Total protein had decreased in infected larvae but activity level of two aminotransferases significantly increased. Therefore, grasseri has a considerable effect on protein metabolism.

  13. Structure of recombinant human carboxylesterase 1 isolated from whole cabbage looper larvae

    International Nuclear Information System (INIS)

    Large quantities of recombinant human carboxylesterase 1 have been produced in an economical whole insect larvae system. The crystal structure of this enzyme is essentially identical to that produced by cell culture techniques. The use of whole insect larvae as a source of recombinant proteins offers a more cost-effective method of producing large quantities of human proteins than conventional cell-culture approaches. Human carboxylesterase 1 has been produced in and isolated from whole Trichoplusia ni larvae. The recombinant protein was crystallized and its structure was solved to 2.2 Å resolution. The results indicate that the larvae-produced enzyme is essentially identical to that isolated from cultured Sf21 cells, supporting the use of this expression system to produce recombinant enzymes for crystallization studies

  14. [Last instar larva and pupa of Melipotis cellaris (Guenée) (Lepidoptera: Noctuidae)].

    Science.gov (United States)

    Vargas, Héctor A

    2010-01-01

    The last instar larva and pupa of Melipotis cellaris (Guenée) are described and illustrated, based on specimens collected in northern Chile, associated with Acacia macracantha (Fabaceae). PMID:21120382

  15. [Description of the last instar larva and pupa of Cryptophlebia cortesi Clarke (Lepidoptera: Tortricidae)].

    Science.gov (United States)

    Vargas, Héctor A

    2006-01-01

    A description of the last instar larva and pupa of Cryptophlebia cortesi Clarke, based on specimens collected on yaro, Acacia macracantha Bonpl & Humb ex Willd. (Fabaceae), in the Chaca valley, Primera Región, Chile, is presented. PMID:18575693

  16. Some factors influencing the immunization of sheep with irradiated Haemonchus contortus larvae

    International Nuclear Information System (INIS)

    Over the last six years, a number of experiments in which sheep were successfully immunized with two doses of 10,000 Haemonchus contortus larvae, irradiated at 60 kR in a gamma source, have been performed by the authors. The failure of such a regimen of immunization with the same strain of larvae is reported in the paper, together with an investigation of the possible causes. From experiments using both irradiated and normal larvae, it was postulated that the strain had lost its original degree of immunogenicity. Subsequently, it was shown that irradiation of the larvae at 40 kR was successful in restoring immunogenicity and producing a degree of protection against challenge similar to that previously reported with 60 kR. It was concluded that, for the strain of H. contortus used, 60 kR was too high a level of irradiation to produce a consistently high degree of protection against challenge. (author). 12 refs, 6 tabs

  17. A Laboratory Practical on the House Building Behaviour of Caddis Larvae

    Science.gov (United States)

    Hansell, M. H.

    1973-01-01

    Describes a laboratory practical on animal behavior suitable for senior secondary school or university biology classes. Several separate exercises relating to the house building behavior of caddis fly larvae are detailed, together with the time required for preparation. (JR)

  18. Distribution of decapod larvae in the Bombay Harbour-Thana-Bassein Creek regions

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, Neelam; Abbas, M.S.; Nair, V.R

    Variations in the abundance and composition of larval decapods were studied from 90 km stretch of the Bombay Harbour-Thana Creek-Bassein Creek (BHTCBC) system for a period of 15 months. The larvae belonged to Penacidea, Caridea, Anomura...

  19. Unusual pseudomyiasis with Musca domestica (housefly larvae in a child with chronic otitis media

    Directory of Open Access Journals (Sweden)

    Zafar Iqbal

    2016-01-01

    Full Text Available Myiasis is a disease caused by fly larvae and aural myiasis is a rare clinic condition often occurring in children or mentally retarded people. We report the case of an unusual presentation of a unilateral aural myiasis in a 3-year-old female child patient belonging to a slum with unilateral chronic otitis media caused by Musca domestica (housefly larvae. Eight larvae were removed from the external auditory canal while five more larvae were located in the middle ear cavity and were removed through perforation of the tympanic membrane. Management of ear myiasis is based on removal of the maggots and cleansing of the ear with ethanol, chloroform, or physiological saline. Physiological saline is preferred in patients who have tympanic membrane perforation. Myiasis is related to personal hygiene. Therefore, to decrease the incidence of these infestations, care, and hygiene standards should be carried out for those at risk through information, education, and communication.

  20. Description of two final stadium Onychogomphus larvae from Thailand (Odonata: Gomphidae).

    Science.gov (United States)

    Chainthong, Damrong; Boonsoong, Boonsatien

    2016-01-01

    The final stadium larvae of Onychogomphus castor Lieftinck and O. duaricus Fraser are described and illustrated for the first time based on reared specimens from Thailand. The taxonomic characteristics of the larvae of the genus Onychogomphus are discussed and summarized. The larva of O. castor differs from other Southeast Asian species in having distinct mid-dorsal spines on S2-9, divergent wing pads reaching S5, and lateral spines on S6-9. The larva of O. duaricus has a weakly swollen third antennal segment, with short blunt mid-dorsal spines on S2-9, divergent wing sheaths reaching the middle of S4, and lateral spines present on S7-9. PMID:27395854

  1. Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    M. Angélica Garrido-Pereira

    2014-11-01

    Full Text Available Cobia (Rachycentron canadum is a marine finfish with good potential for mariculture. This study analyzes the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS. Larvae were stocked into two independent RAS for 26 days after hatching. One of the systems (Probiotic treatment received the addition of a commercial probiotic consisting of B. subtilis, B. licheniformis and B. pumilus directly into the water and by live feed. Survival, final weight and water quality were not affected by probiotics. Results showed larvae of the probiotic treatment demonstrated a greater resistance to salinity stress. Immunohistochemical analysis showed a higher expression of CD4 in probiotic treatment. These results suggest that Bacillus spp. probiotics used in RAS have a potential stimulating impact on immune system differentiation and increases salinity stress resistance of cobia larvae.

  2. Larvae of fouling organisms and macrofouling at New Mangalore Port, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, D.C.; Anil, A.C.; Venkat, K.

    Polychaetes, bryozoans, barnacles and ascidians were the dominant groups in the fouling community at New Mangalore Port. Polychaete and cirripede larvae were encountered throughout the year. Even though bivalve were present in the planktonic hauls...

  3. Description of the larva of Argia chelata Calvert, 1902 (Odonata: Coenagrionidae).

    Science.gov (United States)

    Novelo-Gutiérrez, Rodolfo

    2013-01-01

    The larva of Argia chelata is described and figured. It falls into the group of Argia larvae with a moderately prominent ligula and two palpal seta, but it differs from its closest relatives by having labial palp with 2 setae plus one basal setella; the length of the ligula is 30% of its maximum width; basal tergites (1-5) lacking long, fine setae, mainly on midline; S8-10 mostly dark brown; paraprocts with spiniform setae on basal 0.25 and 0.55 of dorsal and ventral borders, respectively. Larvae were found in 2nd to 4th order shallow streams in cloud forest, crawling among debris, fine sand and mud where the water flow is slow or still, close to the shoreline. The larva is compared with A. lacrimans (Hagen), A. pima Garrison, and A. tonto Calvert, species apparently closely related.  PMID:25113363

  4. Vulnerability of the mosquito larvae to the guppies (Poecilia reticulata in the presence of alternative preys

    Directory of Open Access Journals (Sweden)

    Barnali Manna

    2008-08-01

    Full Text Available Background & objectives: The predatory potential of the larvivorous fishes can be affected by the presence of alternative preys. In the present study the predation pattern of the sewage dwelling Poecilia reticulata (Peters 1872 on the larvae of Culex quinquefasciatus Say 1823 (Diptera: Culicidae was evaluated in the presence of alternative preys. Methods: The predation of Cx. quinquefasciatus larvae by different size groups of P. reticulata fishes was evaluated. In addition to this, the niche breadth (N and diet breadth (B were measured following Manly’s selectivity index (Si as an indicator of variation of such predation pattern in the presence of alternative prey types, like chironomid larvae and tubificid worms.Results: The consumption of IV instar Cx. quinquefasciatus larvae by individual P. reticulata ranged between 65 and 84 in a 3 h feeding period and varied with the size of fish (F2, 33 = 34.91; p<0.001. The selectivity coefficient revealed a significantly low preference for the Cx. quinquefasciatus larvae (0.16, CL: 0.05 – 0.27; p< 0.05 compared to the chironomid larvae and tubificid worms, when all the three prey types were present. The niche breadth (N and diet breadth (B ranged from 0.77 to 0.92 and 0.69 to 0.93, respectively. The total consumption of all the prey types varied with the predator density, but the selectivity index for the mosquito larvae was significantly low in all the instances.Interpretation & conclusion: P. reticulata can consume a good number of mosquito larvae, with the consumption rate varying with the body size. P. reticulata fishes exhibit low preference for mosquito larvae as prey in the presence of alternative controphic preys like chironomid larvae and tubificid worms. Though establishment and sustenance of P. reticulata in new habitats will be favoured by the presence of alternative preys, but vulnerability of mosquito larvae may be reduced with availability of multiple preys in natural conditions.

  5. A complex of genes involved in adaptation of Leptinotarsa decemlineata larvae to induced potato defense

    OpenAIRE

    Petek, Marko; Jongsma, Maarten Anthonie; Turnšek, Neža; Slapar, Nina; Popovič, Tatjana; Pompe Novak, Maruša; Štrukelj, Borut; Buh Gašparič, Meti; Gruden, Kristina

    2015-01-01

    The Colorado potato beetle (Leptinotarsa decemlineata) is the most important pest of potato in many areas of the world. One of the main reasons for its success lies in the ability of its larvae to counteract plant defense compounds. Larvae adapt to protease inhibitors (PIs) produced in potato leaves through substitution of inhibitor-sensitive digestive cysteine proteases with inhibitor-insensitive cysteine proteases. To get a broader insight into the basis of larval adaptation to plant defens...

  6. Abundance and dynamics of anopheline larvae in a highland malarious area of south-central Ethiopia

    OpenAIRE

    Animut Abebe; Gebre-Michael Teshome; Balkew Meshesha; Lindtjørn Bernt

    2012-01-01

    Abstract Background Malaria is a public health problem in Ethiopia, and increasingly so in highland areas, possibly because of global warming. This study describes the distribution, breeding habitat and monthly dynamics of anopheline larvae in Butajira, a highland area in south-central Ethiopia. Methods A study of the abundance and dynamics of Anopheles larvae was undertaken at different sites and altitudes in Butajira from July 2008 to June 2010. The sites included Hobe (1817 m.a.s.l), Diram...

  7. Chemical Composition and Food Potential of Pachymerus nucleorum Larvae Parasitizing Acrocomia aculeata Kernels

    OpenAIRE

    Ariana Vieira Alves; Eliana Janet Sanjinez Argandoña; Adelita Maria Linzmeier; Claudia Andrea Lima Cardoso; Maria Lígia Rodrigues Macedo

    2016-01-01

    Insect consumption as food is culturally practiced in various regions of the world. In Brazil, there are more than 130 species of edible insects registered, from nine orders, among which stands out the Coleoptera. The larva of the beetle Pachymerus nucleorum Fabricius, 1792, grows into the bocaiuva fruit (Acrocomia aculeata (Jacq.) Lodd. Ex Mart., 1845), which has proven nutritional quality. The aim of this work was to evaluate the nutritional potential of P. nucleorum larvae compared to boca...

  8. Influence of UV-irradiation on the nauplius larvae of the barnacle Chthamalus sp

    International Nuclear Information System (INIS)

    The purpose of this study is to investigate the influence of UV-irradiation on the nauplius larvae of the barnacle and to use this as the basis for researching the possibility of UV-irradiation as a new method for anti-macrofouling control. The nauplius larvae in the petri dishes were exposed to UV-irradiation (λ max = 253.7 nm), then the larval states and behaviour were observed. UV-intensisties were 3.0 mW·cm-2 -7.0 mW·cm-2 and the exposure time was 15 sec -10 min. The water in the petri dishes was changed intermittently but the larvae were not fed. The results were as follows: 1) UV-irradiation may have a delayed lethal effect and metamorphosis-inhibitory effect on the nauplius larvae. 2) The lethal effect of the sum of the dosages of UV on the larvae may nearly equate each other despite differences in each UV-intensity. 3) Within ca. 72 hr, 100 % of UV-irradiated larvae were dead with the dosage of at least 672 mW·sec·cm-2 and were incapable of swimming with the dosage of at least 168 mW·sec·cm-2. 4) UV-irradiated larvae could not exuviate with the dosage of at least 246 mW·sec·cm-2 and could only exuviate with the dosage of 45 mW·sec·cm-2. 5) After UV-irradiation even the 'actively swimming' larvae may have suffered some sort of physiological damage. (author)

  9. Ontogeny and physiology of the digestive system of marine fish larvae

    OpenAIRE

    Zambonino, Jose-luis; Gisbert, E.; Sarasquete, C.; Navarro, I.; J. Gutiérrez; Cahu, Chantal

    2008-01-01

    The ontogeny of the digestive tract of marine fish larvae has been the subject of many studies these last twenty years. Beyond the scientific interest for such animal species, particularly for developmental aspects, most of these studies aimed to come up with the expectations of commercial hatcheries by reducing the bottlenecks in larvae culture and weaning processes (switch from live preys to compound diet feeding sequence). Consequently, the profile and dietary adaptation of digestive enzym...

  10. Transformation and Mineralization of Organic Matter by the Humivorous Larva of Pachnoda ephippiata (Coleoptera: Scarabaeidae)

    OpenAIRE

    Li, Xiangzhen

    2004-01-01

    Scarabaeidae beetle larvae are widely distributed in various ecosystems, which numerous species that either co-operate in soil processes or at least live in soil at some stage in their development, and play important roles in organic matter transformation and soil development. The larvae of Scarabaeidae have been mainly considered in the context of fiber degradation, e.g., the digestion of plant biomass in various stages of decomposition. However, their food spectrum is apparently much broade...

  11. Ingestion by Japanese Eel Anguilla japonica Larvae on Various Minute Zooplanktons

    OpenAIRE

    Wullur, Stenly; Yoshimatsu, Takao; Tanaka, Hideki; Ohtani, Masataka; Sakakura, Yoshitaka; Kim, Hee-Jin; Hagiwara, Atsushi

    2013-01-01

    We observed the feeding incidence of Japanese eel Anguilla japonica larvae of 6, 7, 8 and 14 days after hatching (DAH) using various minute zooplanktons such as rotifer (Proales similis, Synchaeta sp., Keratella sp., Brachionus rotundiformis, B. angularis) and nauplii of copepod Paracyclopina nana, and compared those results to slurry type diets (i.e., shark eggs for control) to evaluate the usability of these planktons as primary food source for the mass culture of eel larvae. Feeding incid...

  12. Metalloproteases of infective Ancylostoma hookworm larvae and their possible functions in tissue invasion and ecdysis.

    OpenAIRE

    Hotez, P; HAGGERTY, J; Hawdon, J.; Milstone, L; Gamble, H R; Schad, G.; Richards, F

    1990-01-01

    To infect their hosts, hookworm larvae must exsheath and migrate through connective tissue. A modified in vitro skin chamber was used to show that the human hookworm Ancylostoma duodenale and the zoonotic canine hookworm Ancylostoma caninum penetrate epidermis, basement membrane, and dermis in similar ways. These similarities in tissue invasion properties reflect the observed biochemical similarities in parasite protease composition. The larvae of both species contain protease activity that i...

  13. Seasonal and Topographical Factors Affecting Breeding Sites of Culex Larvae in Nakhon Si Thammarat, Thailand

    OpenAIRE

    Warabhorn PREECHAPORN; Mullica JAROENSUTASINEE; Krisanadej JAROENSUTASINEE; Jirawat SAETON

    2007-01-01

    This study investigated how the seasons affect the key breeding sites of Culex larvae in three topographical areas: mangrove, rice paddy and mountainous areas. We examined how the number of Culex larvae varied in different types of water containers. Water containers were categorised into the following groups: indoor/outdoor containers, artificial/natural containers, earthen/plastic containers, containers with/without lids and dark/light coloured containers. Samples were collected from 300 hou...

  14. Haemolymph electrophoretic pattern of Ascia monuste orseis larvae (Lepidoptera: pieridae parasitized by Cotesia glomerata (Hymenoptera: braconidae

    Directory of Open Access Journals (Sweden)

    M. Scaglia

    2003-01-01

    Full Text Available Cotesia glomerata is a natural enemy of the vegetable plague Ascia monuste orseis and preferably parasites 2nd, 3rd and 4th instar larvae. Parasitism effects on the haemolymph protein profile of Ascia monuste orseis larvae from the 2nd to 7th days were analyzed both qualitatively and quantitatively by SDS-PAGE and Coomassie-Blue binding methods. Quantitative analysis showed a progressive increase in the protein content of about 6.5 and 12.5 times in parasitized and non-parasitized larvae from the 2nd to 5th days, respectively. On the 6th day, a decrease in protein content was observed in both groups, although this decrease was significantly less than the control group that continued to metamorphosis. Meanwhile, parasitized larvae had one more day (7th day in their larval period to complete parasitoid development, justified by the fact that parasitoid is koinobiont and allows host feeding. On this day, a drastic increase in protein content was detected when the parasitoids left the host. The SDS-PAGE showed proteins of high molecular weight (>120 kDa on the 5th day of the non-parasitized larvae when they entered pre-pupa stage and on the 7th day of parasitized larvae. Proteins with MW lower than 62 kDa and higher than 27 kDa were absent on the 5th day in control larvae (pre-pupa phase, but present in parasitized larvae. This could indicate a possible relation between these proteins and the host juvenile hormone. Therefore, the presence of C. glomerata influences Ascia monuste orseis development, but its own physiological development is apparently independent of the host, which tends to die when parasitism succeeds.

  15. The Study Of The Insecticidal Effect Of Nigella Sativa Essential Oil Against Tuta Absoluta Larvae

    OpenAIRE

    Benchouikh Adil; Allam Tarik; Abderrahim Kribii; Khadija Ounine

    2015-01-01

    Abstract To contribute to the development of an integrated strategy of pests associated with the tomato crop the insecticidal potential of the essential oil of Nigella sativa was evaluated on larvae of Tuta absoluta which is considered the most destructive insect in the production of tomato Solanum lycopersicum and which causes serious damages in invaded areas. Rearing larvae of Tuta absoluta and the testing of toxicity were conducted in laboratory conditions in petri dishes at a temperature ...

  16. Isolation and characterization of a novel phage lysin active against Paenibacillus larvae, a honeybee pathogen

    OpenAIRE

    LeBlanc, Lucy; Nezami, Sara; Yost, Diane; Tsourkas, Philippos; Amy, Penny S.

    2015-01-01

    Paenibacillus larvae is the causative agent of American foulbrood (AFB) disease which affects early larval stages during honeybee development. Due to its virulence, transmissibility, capacity to develop antibiotic resistance, and the inherent resilience of its endospores, Paenibacillus larvae is extremely difficult to eradicate from infected hives which often must be burned. AFB contributes to the worldwide decline of honeybee populations, which are crucial for pollination and the food supply...

  17. Composting poultry manure by fly larvae (Musca domestica) eliminates Campylobacter jejuni from the manure

    OpenAIRE

    Nordentoft, Steen; Hald, Birthe

    2013-01-01

    Introduction The common house fly, Musca domestica (Md) is an important carrier of zoonotic agents, and Campylobacter jejuni is one that may be transmitted between animals and humans by flies. Colonized animals shed the bacteria in feces where larval stages of Md flies develops. Aim of the present study To monitor fly larvae composting of poultry manure artificially contaminated with C. jejuni, and to investigate a possible transmission route of C. jejuni from the manure through the fly larva...

  18. Feeding chickens fly larvae (Musca domestica) protein improves gut health and performances

    OpenAIRE

    Nordentoft, Steen; Engberg, Ricarda M

    2014-01-01

    In a feeding trial 450 layer chickens were fed either of 3 isoenergetic diets supplemented with different fish meal, grounded fly meal (Musca domestica) or fly meal and fresh fly larvae. The purpose of this study was to investigate the possibility of feeding grounded fly larva to layer chickens as an alternative protein source for fish meal in organic poultry. Parameters investigated were weight gain, food consumption, animal behavior and study whether it would have effect on intestinal health.

  19. Susceptibility of Aedes aegypti larvae to the insecticide temephos in the Federal District, Brazil

    OpenAIRE

    de Carvalho, M.D.S.; Caldas, E.D.; Dégallier, Nicolas; Vilarinhos, P.D.T.; de Souza, L.; Amelia, M.; Yoshizawa, C.; M. B. KNOX; Oliveira, C

    2004-01-01

    Objective: To study the susceptibility status of Aedes aegypti to the organophosphate insecticide temephos. Methods: Samples of Ae. aegypti larvae were obtained, using ovitraps, from eight cities of the Federal District, central Brazil, in 2000 and 2001. Larvae were submitted to the diagnostic dose of 0.012 mg/l temephos, as recommended by standard World Health Organization methodology. Field populations were tested in parallel with reference strains Rockefeller and DIVAL, from the Environmen...

  20. Distribution of oyster Ostrea edulis, mussel Mytilus edulis and Anomiid larvae in Bertraghboy Bay, Co. Galway

    OpenAIRE

    Wilson, J H

    1988-01-01

    Concentrations and shell lengths of Mytilus edulis, Ostrea edulis and Anomiid larvae were recorded from April to October 1985 in Bertaghboy Bay, Co. Galway. The gamete volume fraction off eggs in female mussels was recorded in an introduced cultivated population of mussels in the inner bay during 1985. Oyster larvae were commonest in July and September, but were concentrated in the upper bay. Mussel and Anomiid distributions were more variable. While the commercial stocks of mussels in the ba...