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Lorraine Maltby - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Gammarus Pulex in situ feeding assay as a biomonitor of water quality: Robustness, responsiveness, and relevance
Environmental Toxicology and Chemistry, 2002Co-Authors: Lorraine Maltby, Sophie A. Clayton, Robert M Wood, Niaobh McloughlinAbstract:Biomonitoring using benthic macroinvertebrates has been used to assess water quality in Europe since the early 20th century. Most methods use community-level measurements, and the use of single-species responses has been limited, despite their potential benefits as sensitive, early warning indicators. Here we evaluate a single-species in situ assay in which the response is feeding inhibition of the freshwater amphipod Gammarus Pulex. The assay was deployed in uncontaminated reference sites to quantify background variability in feeding rates and to elucidate sources of this variation. The ability of the assay to detect impacts of point-source discharges was assessed and the ecological relevance of the assay determined by comparing assay responses to aspects of community structure and functioning. Water temperature accounted for 76% of the variation in the feeding rate of animals deployed at uncontaminated sites, and summer deployments had a >90% power to detect a 30% inhibition in feeding. Inhibition of the situ feeding rate of G. Pulex deployed downstream of a variety of point-source discharges ranged from 27 to 99.6%. Gammarus Pulex is an important detritivore in stream communities, and a strong positive correlation existed between in situ feeding rate measured over 6 d and leaf decomposition measured over 28 d. A positive correlation also existed between in situ feeding and macroinvertebrate diversity and a biotic index. The G. Pulex in situ feeding assay is a short-term sublethal biomonitor of water quality that is indicative of community- and ecosystem-level responses occurring over longer time periods. It is robust, responsive, and relevant.
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Anaerobic capacity of a crustacean sensitive to low environmental oxygen tensions, the freshwater amphipod Gammarus Pulex (L.)
Hydrobiologia, 2002Co-Authors: John I. Spicer, C. Lucy Dando, Lorraine MaltbyAbstract:We investigated the accumulation of haemolymph L-lactate in response to anoxia, progressive hypoxia and activity, in a species that rarely encounters low PO2 in its natural environment, the freshwater amphipod Gammarus Pulex (L.). Individuals survived
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Responses of Gammarus Pulex (Amphipoda, Crustacea) to metalliferous effluents: identification of toxic components and the importance of interpopulation variation.
Environmental Pollution, 1994Co-Authors: Lorraine Maltby, Mark CraneAbstract:This study was designed to evaluate the ability of an in-situ bioassay to assess the impact of complex effluents on freshwaters and to identify toxic components. Reductions in the feeding rate of Gammarus Pulex proved to be a sensitive indicator of the impact of metalliferous effluents on receiving water quality. The effluents contained a mixture of five potentially toxic metals. By combining information on feeding rates with bioaccumulation data, two metals, iron and manganese, were identified as the probable toxic agents. Laboratory experiments validated the conclusions reached from the field study and confirmed that iron was a major toxicant. The sensitivities of Gammarus Pulex from a metal-contaminated site and a clean site were compared during both the field and laboratory studies. Interpopulation differences in the response of G. Pulex to toxicants were detected in the field study but not in the laboratory experiments. Possible reasons for this are discussed.
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Comparative ecology of Gammarus Pulex (L.) and Asellus aquaticus (L.) II: fungal preferences
Hydrobiologia, 1994Co-Authors: Manuel A. S. Graça, Lorraine Maltby, Peter CalowAbstract:This paper continues to explore niche differentiation in Gammarus Pulex and Asellus aquaticus by analysis of their food preferences. Individuals from both species discriminated between leaf discs colonized by different fungal species and exhibited strong preferences for Anguillospora longissima and Heliscus lugdunensis. Fungal preferences were not correlated with the relative abundance of fungi in the field and there was considerable intra-population variability in food preferences — both between individuals and for the same individual through time. Niche overlap between animals from all four study populations was high and there was no evidence of differences in the potential trophic niches of animals from sympatric and allopatric populations.
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Importance of fungi in the diet of Gammarus Pulex and Asellus aquaticus I: feeding strategies
Oecologia, 1993Co-Authors: Manuel A. S. Graça, Lorraine Maltby, Peter CalowAbstract:The importance of fungi in the trophic biology of the freshwater detritivores Gammarus Pulex and Asellus aquaticus was investigated. Inspection of leaves used in feeding trials indicated that whereas A. aquaticus scrapes at the leaf surface, G. Pulex bites through the leaf material. Both species discriminated between fungal mycelia, fungally colonized and uncolonized leaf material but, although A. aquaticus selectively consumed fungal mycelia, G. Pulex fed preferentially on leaf material. Fungi appear to be an important food source for A. aquaticus and selection of food material was positively correlated with fungal biomass. In contrast, for G. Pulex, fungi appear to be more important as modifiers of leaf material. However, no significant correlations were found between food preference and any of the leaf modifications measured.
Olivier Geffard - One of the best experts on this subject based on the ideXlab platform.
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shotgun proteomics datasets acquired on Gammarus Pulex animals sampled from the wild
Data in Brief, 2019Co-Authors: Duarte Gouveia, Yannick Cogne, Jeancharles Gaillard, Christine Almunia, Olivier Pible, Adeline Francois, Davide Degliesposti, Olivier Geffard, Arnaud Chaumot, Jean ArmengaudAbstract:Abstract This data article associated with the manuscript “Comparative proteomics in the wild: accounting for intrapopulation variability improves describing proteome response in a Gammarus Pulex field population exposed to cadmium” refers to the shotgun proteomics analysis performed on 40 Gammarus Pulex animals sampled from the wild. Proteins were extracted, digested with trypsin, and the resulting peptides were identified by tandem mass spectrometry. Here, we present the list of proteins from males and the list of proteins from females that are differentially detected between the Brameloup and the Pollon populations. Data are available via ProteomeXchange with identifiers PXD013656 and PXD013712, respectively.
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Physiological and behavioural responses of Gammarus Pulex exposed to cadmium
Comparative Biochemistry and Physiology - Part C: Toxicology and Pharmacology, 2008Co-Authors: Vincent Felten, G. Charmantier, M. Charmantier-daures, F. Aujoulat, Jeanne Garric, Olivier GeffardAbstract:Physiological and behavioural responses of the acid-sensitive amphipod Gammarus Pulex exposed to a wide range of acid conditions (pH 4.1, 5.1, 6.0) under laboratory conditions were investigated. An exposure of 38h to acid conditions caused significant decreases in survival rate, osmolality, haemolymph Na+ concentration, ventilatory and locomotor activity compared to organisms exposed to a circumneutral medium (pH 7.9). We highlighted the interest of using individual response distribution, since drastic effects can be detected in organisms exposed to pH 6.0, in particular for osmolality: the response can be divided into two groups, unimpacted and impacted organisms. Moreover this representation permitted to evaluate the health level of individual organisms through the determination of threshold values. Significant correlations between mean pH and mean physiological/behavioural responses were observed. The relationships between individual responses permitted not only to compare endpoints, but also to show that affected organisms were impacted by ionoregulation failure, hypoventilation and low locomotor activity. The energetic reallocation in favour of maintenance functions, such as osmoregulation, is discussed. The results of this study indicate that the values of haemolymph Na+ concentration, osmolality and locomotor activity in G. Pulex could be effective ecophysiological/behavioural markers to monitor freshwater ecosystems and to assess the health of organisms or populations.
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Influence of biotic and abiotic factors on metallothionein level in Gammarus Pulex
Comparative Biochemistry and Physiology - Part C: Toxicology and Pharmacology, 2007Co-Authors: Alain Geffard, Hervé Quéau, O. Dedourge, S. Biagianti-risbourg, Olivier GeffardAbstract:Detection and assessment of the impact of pollution on biological resources imply increasing research on early-warning markers such as metallothioneins in metal exposure. Metallothioneins are cytosolic, low-molecular-weight proteins, involved principally in essential metal homeostasis and non-essential metal detoxication. Metallothionein synthesis could be influenced by abiotic (season) or biotic (reproduction process) factors directly or indirectly by its effect on metal bio-accumulation (i.e., sex, weight). In view of using metallothioneins as metal-exposure biomarkers in Gammarus Pulex, this study attempts to define the effect of several factors (sex, weight/size and season) on the level of this protein. Metallothionein levels recorded in individuals over a large range of weights indicate a negative correlation between them. Inversely in our conditions, no difference was observed between male and female organisms. During field study, metallothionein level changes were observed with the highest levels in autumn and winter periods. The highest metallothionein levels were observed after the reproduction period, perhaps with the metabolic needs of biologically available essential metal such as zinc.
D. Pascoe - One of the best experts on this subject based on the ideXlab platform.
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Effects of lindane on the growth of the freshwater amphipod Gammarus Pulex (L.)
Chemosphere, 1996Co-Authors: Sj Blockwell, D. Pascoe, E.j. TaylorAbstract:Abstract A bioassay for determining the effects of toxicants on the growth of a sensitive life stage of Gammarus Pulex (L.) is described. The experimental design minimised variation: a non-destructive weighing technique produced initial treatment groups with a low coefficient of variation for mean wet weight and also facilitated the introduction of a standard artificial diet regime. The chemical investigated was the organochlorine insecticide lindane for which the lowest observed (LOEC) and no observed effect concentrations (NOEC) of 6.1 and 2.7 μgl −1 respectively were determined after the 14 day exposure period. These results are compared to toxicity data from other studies.
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Laboratory and field evaluation of a behavioural bioassay—The Gammarus Pulex (L.) precopula separation (GaPPS) test
Water Research, 1994Co-Authors: D. Pascoe, Steve J. Maund, T.j. Kidwards, E. Muthi, E.j. TaylorAbstract:Abstract A bioassay, based upon the reproductive behaviour of the amphipod Gammarus Pulex , was evaluated for its application in detecting freshwater pollutants. In the laboratory the bioassay proved to be useful in rapidly detecting a wide range of pollutants at concentrations significantly below those causing acute lethal toxicity and in the field it responded rapidly to a variety of pollutant inputs. The results indicate that this bioassay is simple, cost-effective and reliable and could be employed effectively for detecting and quantifying pollutants.
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The importance of food and water as sources of zinc during exposure of Gammarus Pulex (Amphipoda)
Archives of Environmental Contamination and Toxicology, 1994Co-Authors: D. PascoeAbstract:The bioaccumulation of zinc by the freshwater shrimp Gammarus Pulex (L.) and adsorption by its food, conditioned horsechestnut leaves (Aesculus hippocastanum L.), in two zinc exposure concentrations were studied in the laboratory. The bioconcentration factors (BCF), uptake and elimination rate constants, and assimilation rate from food were calculated for one exposure concentration using a two-trophic-level model of a food chain. The BCF of the conditioned horse chestnut leaves was more than five times higher than that of G. Pulex, and the assimilation rate of zinc from food by Gammarus was only 1.4%. As with many other animals, G. Pulex was able to regulate its total body zinc level, and to accumulate most of the metal from water rather than from its food.
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The bioconcentration of zinc by Gammarus Pulex (L.) and the application of a kinetic model to determine bioconcentration factors
Water Research, 1993Co-Authors: Qin Xu, D. PascoeAbstract:Abstract The bioconcentration, and subsequent elimination, of zinc by the freshwater amphipod Gammarus Pulex (L.) were determined experimentally in the laboratory at five zinc exposure concentrations (0.41–2.02 mg/l). A first-order kinetic model, modified for naturally occurring trace chemicals, was then used to calculate uptake ( K 1 ) and elimination ( K 2 ) rate constants from which the bioconcentration factors (BCF) could be predicted. Good agreement was found between the recorded and predicted BCFs and it is suggested that the model could have wider use for the study of substances naturally present at trace levels within animal tissues.
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A new method for measuring the feding activity of Gammarus Pulex (L.)
Chemosphere, 1993Co-Authors: E.j. Taylor, D.p.w. Jones, Steve J. Maund, D. PascoeAbstract:Abstract A new method is described which quantifies the feeding activity of the freshwater amphipod Gammarus Pulex (L.). The bioassay, which utilises a time response analysis of the feeding of G. Pulex on eggs of Artemia salina, is rapid and non-destructive allowing the frequent monitoring of test organisms during both toxicological and autecological studies.
Niaobh Mcloughlin - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Gammarus Pulex in situ feeding assay as a biomonitor of water quality: Robustness, responsiveness, and relevance
Environmental Toxicology and Chemistry, 2002Co-Authors: Lorraine Maltby, Sophie A. Clayton, Robert M Wood, Niaobh McloughlinAbstract:Biomonitoring using benthic macroinvertebrates has been used to assess water quality in Europe since the early 20th century. Most methods use community-level measurements, and the use of single-species responses has been limited, despite their potential benefits as sensitive, early warning indicators. Here we evaluate a single-species in situ assay in which the response is feeding inhibition of the freshwater amphipod Gammarus Pulex. The assay was deployed in uncontaminated reference sites to quantify background variability in feeding rates and to elucidate sources of this variation. The ability of the assay to detect impacts of point-source discharges was assessed and the ecological relevance of the assay determined by comparing assay responses to aspects of community structure and functioning. Water temperature accounted for 76% of the variation in the feeding rate of animals deployed at uncontaminated sites, and summer deployments had a >90% power to detect a 30% inhibition in feeding. Inhibition of the situ feeding rate of G. Pulex deployed downstream of a variety of point-source discharges ranged from 27 to 99.6%. Gammarus Pulex is an important detritivore in stream communities, and a strong positive correlation existed between in situ feeding rate measured over 6 d and leaf decomposition measured over 28 d. A positive correlation also existed between in situ feeding and macroinvertebrate diversity and a biotic index. The G. Pulex in situ feeding assay is a short-term sublethal biomonitor of water quality that is indicative of community- and ecosystem-level responses occurring over longer time periods. It is robust, responsive, and relevant.
Vincent Felten - One of the best experts on this subject based on the ideXlab platform.
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Single and combined effects of cadmium and arsenate in Gammarus Pulex (Crustacea, Amphipoda): understanding the links between physiological and behavioural responses.
Aquatic Toxicology, 2013Co-Authors: Céline Vellinger, Eric Gismondi, Vincent Felten, Philippe Rousselle, Kahina Mehennaoui, Marc Parant, Philippe Usseglio-polateraAbstract:This study aimed at investigating the individual and interactive effects of cadmium (Cd) and arsenate (AsV) in Gammarus Pulex (Crustacea, Amphipoda) through the use of several biomarkers. Individuals were exposed for 240 h to two concentrations of AsV or Cd alone, and all the possible binary mixtures of these concentrations of AsV and Cd in a complete factorial design. The pattern of the biomarkers' responses to Cd and AsV alone or in mixture was similar in Gammarus Pulex, even if the response intensity varied depending on the tested conditions. G. Pulex responded to contamination with increased mobilization of the detoxification systems [i.e. γ-glutamyl-cystein ligase activity (GCL), reduced glutathione content (GSH) and metallothionein concentrations (MT)]. This response seems to imply changes in energy reserve utilization (total lipids and proteins are used prior to glycogen reserves), but also a possible energy reallocation from locomotion to detoxification processes. The observed increase in lipid peroxidation could be relied to the increasing gammarid mortality, despite the higher mobilization of detoxification systems. Even if the outcome of the complex interactions between AsV and Cd remains difficult to unravel, such studies are critically important for better assessing the effects of stressors on organisms, populations and communities in a multi-contamination context of ecosystems.
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Physiological and behavioural responses of Gammarus Pulex exposed to cadmium
Comparative Biochemistry and Physiology - Part C: Toxicology and Pharmacology, 2008Co-Authors: Vincent Felten, G. Charmantier, M. Charmantier-daures, F. Aujoulat, Jeanne Garric, Olivier GeffardAbstract:Physiological and behavioural responses of the acid-sensitive amphipod Gammarus Pulex exposed to a wide range of acid conditions (pH 4.1, 5.1, 6.0) under laboratory conditions were investigated. An exposure of 38h to acid conditions caused significant decreases in survival rate, osmolality, haemolymph Na+ concentration, ventilatory and locomotor activity compared to organisms exposed to a circumneutral medium (pH 7.9). We highlighted the interest of using individual response distribution, since drastic effects can be detected in organisms exposed to pH 6.0, in particular for osmolality: the response can be divided into two groups, unimpacted and impacted organisms. Moreover this representation permitted to evaluate the health level of individual organisms through the determination of threshold values. Significant correlations between mean pH and mean physiological/behavioural responses were observed. The relationships between individual responses permitted not only to compare endpoints, but also to show that affected organisms were impacted by ionoregulation failure, hypoventilation and low locomotor activity. The energetic reallocation in favour of maintenance functions, such as osmoregulation, is discussed. The results of this study indicate that the values of haemolymph Na+ concentration, osmolality and locomotor activity in G. Pulex could be effective ecophysiological/behavioural markers to monitor freshwater ecosystems and to assess the health of organisms or populations.
