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Sample records for spiny-cheek crayfish orconectes

  1. Evaluation of different marking methods for spiny-cheek crayfish (Orconectes limosus

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    Buřič M.

    2008-10-01

    Full Text Available Different methods of marking were evaluated for Orconectes limosus (CL = carapace length, 12–37 mm under laboratory conditions: the use of passive integrated transponders, visible implant elastomers, visible implant alphanumeric tags, and cauterization. High survival (> 90% was obtained with all methods tested. Tag retention and readability were evaluated immediately after marking, before and after ecdysis, with moult increments and number of moults been recorded. Marking using cauterization negatively affects the percent moult increment (PMI of crayfish. The average PMI of 15 ± 0.88% did not differ between males (15 ± 1.41 mm and females (15 ± 1.12 mm. It was found that PMI gradually decreased with an increase in CL. Sixty-one moults were observed, with 12 crayfish (6 juveniles and 6 adults presenting two moults. Time between moults varied from 3 to 7 weeks. CL was increased with over 28 ± 2.68% due to two moults. Three females moulted twice after successful hatching and carrying of juveniles.

  2. Heavy Metals Bioaccumulation in Tissues of Spiny-Cheek Crayfish (Orconectes limosus) from Lake Gopło: Effect of Age and Sex.

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    Stanek, Magdalena; Dąbrowski, Janusz; Różański, Szymon; Janicki, Bogdan; Długosz, Jacek

    2017-06-01

    The aim of the present work was to assess the concentrations of metals in the abdominal muscle and exoskeleton of 3-year-old males and 4-year-old females and males of spiny-cheek crayfish (Orconectes limosus) collected from Lake Gopło. A total of 93 males and 35 females were collected in autumn (October 2014). The analyzes of heavy metals were conducted by means of atomic absorption spectroscopy with a PU9100X spectrometer. The content of mercury was determined using AMA 254 mercury analyser. As analyses indicated heavy metals accumulated in the muscle and exoskeleton in the following sequence: Zn > Cu > Pb > Mn > Ni > Hg and Mn > Pb > Zn > Ni > Cu > Hg, respectively. Statistically significant differences between 3- and 4-year-old males were found for all analyzed metals. Gender dependent differences were calculated only for Ni in the muscle tissue and for Mn and Hg in the exoskeleton. In comparison with the study carried out 2 years ago notably higher concentrations of Pb were found in the muscle and a higher content of Zn, Pb, Mn and Ni was determined in the exoskeleton.

  3. Temporal variation in the prevalence of the crayfish plague pathogen, Aphanomyces astaci, in three Czech spiny-cheek crayfish populations

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    Matasová K.

    2011-06-01

    Full Text Available North American crayfish species are natural hosts of the crayfish plague pathogen Aphanomyces astaci. The spiny-cheek crayfish Orconectes limosus, widespread in Central Europe, is the main reservoir of A. astaci in Czech Republic. We tested if there are temporal changes in the prevalence of infected individuals (i.e., the proportion of individuals in which the pathogen is detected in spiny-cheek crayfish populations. Crayfish from three populations shown previously to be infected to different extents (high, intermediate and low, were repeatedly sampled in different years (2004–2010 and seasons. The presence of A. astaci in the soft abdominal crayfish cuticle was tested by specific amplification of the pathogen DNA. There was no substantial temporal variation in pathogen prevalence in the highly and very lowly infected populations. However, a significant long-term as well as seasonal decrease was found in the intermediately infected population. This decline could be related to a decrease in population density over the studied years, and to crayfish seasonal moulting, respectively. A reliable estimate of pathogen prevalence in American crayfish populations thus requires repeated monitoring over years, preferably during the same season before the main period of crayfish moulting.

  4. Temporal variation in the prevalence of the crayfish plague pathogen, Aphanomyces astaci, in three Czech spiny-cheek crayfish populations

    Czech Academy of Sciences Publication Activity Database

    Matasová, K.; Kozubíková, E.; Svoboda, J.; Jarošík, Vojtěch; Petrusek, A.

    -, č. 401 (2011), s. 1-9 ISSN 1961-9502 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : crayfish plague * molecular methosd * dominance Subject RIV: EH - Ecology, Behaviour Impact factor: 1.520, year: 2011

  5. Tritium uptake kinetics in crayfish (Orconectes immunis)

    International Nuclear Information System (INIS)

    Patrick, P.H.

    1985-06-01

    Uptake of tritiated water (HTO) by Orconectes immunis was investigated under laboratory conditions. Tritium uptake in the tissue-free water fraction (TFWT) was described using an exponential model. When steady-state was reached, the ratio of TFWT to HTO was approximately 0.9. Uptake of tritium in the organically-bound fraction (OBT) proceeded slowly, and had not reached steady-state after 117 days of culture. Although steady-state was never reached, the maximum observed ration of OBT to TFWT in whole animals was approximately 0.6. However, this ratio exceeded unity in the exoskeleton. Specific activity ratios of OBT between crayfish and lettuce (food source) were less than or at unity for various test conditions

  6. Ontogenetic Variation in Food Consumption of Rusty Crayfish (Orconectes rusticus) in a Central New York Stream

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    Johnson, James H.; Nack, Christopher C.

    2010-01-01

    We examined feeding periodicity of three size groups of the rusty crayfish (Orconectes rusticus) at four-hour intervals over a 28-hour period during July in a headwater stream of the Susquehanna River drainage in central New York. Feeding activity was expressed as the ratio of stomach weight divided by the crayfish wet weight. The diel food consumption patterns of all three size groups of rusty crayfish (i.e., ≤ 10 mm, 11–20 mm, and > 20 mm carapace length) were significantly different. Peak feeding of the smallest crayfish occurred during crepuscular periods. Food consumption of the intermediate size crayfish was highest at 2000 h, and feeding of large crayfish was consistently high from 1200 h to 0400 h. Feeding intensity of both small and intermediate size crayfish was highest when feeding intensity of large crayfsh was lowest. Ontogenetic differences in feeding periodicity may be associated with predation pressure from large rusty crayfish on smaller individuals.

  7. SHELTERING BEHAVIOUR OF SPINYCHEEK CRAYFISH (ORCONECTES LIMOSUS IN THE PRESENCE OF AN ARTIFICIAL MAGNETIC FIELD

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    TAŃSKI A.

    2005-07-01

    Full Text Available The potential of artificial hideouts, outfitted with magnets or their imitations (control, to attract spinycheek crayfish Orconectes limosus was studied. The experiments were carried out within 1999-2002 in an 80-hectar natural lake. There were three parallel setups, with three experimental treatments (hideouts each. The presently acquired results suggest explicitly that the magnetic field generated at the entrance to the hideouts (made of ceramic pipes, affects the movement direction of crayfish. This was evident from statistically significant differences between the numbers of crayfish attracted to the pipes equipped with magnets and to the control ones.

  8. Habitat use and growth of the western painted crayfish Orconectes palmeri longimanus

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    Dyer, Joseph J.; Mouser, Joshua; Brewer, Shannon K.

    2016-01-01

    Identifying ontogenetic shifts in habitat use by aquatic organisms is necessary for improving conservation strategies; however, our ability to designate life stages based on surrogate metrics (i.e., length) is questionable without validation. This study identified growth patterns of age-0 western painted crayfish Orconectes palmeri longimanus (Faxon, 1898) reared in the laboratory, provided support for field-based designations of age-0 lengths, and identified microhabitat factors important to adult and juvenile presence from field collections. Two growth periods of a laboratory crayfish population were described using a broken line model: a rapid, early-growth period (weeks 2-20, slope = 0.81 ± 0.03SE), and a slower, late-growth period (weeks 22-50, slope = 0.13 ± 0.03SE). A smoothed curve was generated to represent the size distribution of juveniles from our laboratory population to determine the probability that an age-0 crayfish from our laboratory population had a carapace length (CL) similar to that found in previous field studies using onset of maturity (22.4 mm CL). We determined that the probability of the age-0 crayfish in our summer laboratory population exceeding 22.4 mm CL was 0.06. The threshold between the lower 0.95 and upper 0.05 probabilities was 22.9 mm CL, confirming previous field observations of onset at maturity. We used this threshold to identify juveniles and adults from our field collections, and found that both life stages were positively associated with coarse substrate and negatively associated with water depth. Adults, however, were negatively related to gravel, whereas juveniles showed a positive relationship. This result is reflective of the relationship between crayfish body size and refuge use within the interstitial spaces of substrates, whereby adult crayfish are unable to seek refuge in the small interstitial spaces of gravel.

  9. Sublethal copper toxicity impairs chemical orientation in the crayfish, Orconectes rusticus.

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    Lahman, Sara E; Trent, Kaitlyn R; Moore, Paul A

    2015-03-01

    Before reaching concentrations that are high enough to cause mortality, elevated levels of chemical pollution can significantly alter a keystone indicator species' ability to extract sensory information. To organisms that rely on chemical signals to make crucial ecological decisions, increased amounts of a pollutant may impact chemoreceptive abilities by altering the perception of the sensory landscape or impairing the functioning of sensory organs. Heavy metal pollutants entering an aquatic ecosystem are of increasing concern due to discernible effects on chemoreception in many ecologically and economically important species. In order to determine the effects of sublethal copper toxicity on chemically mediated behavior, male and female rusty crayfish, Orconectes rusticus, were exposed to ecologically relevant concentrations of copper (4.5, 45, and 450 µg/l) for 120 h. Following exposure, crayfish were allowed to orient toward a food odor stimulus. During orientation trials, select crayfish oriented under a point or nonpoint source copper background pollutant at the same concentration as the exposure period. Orientation trials were videotaped and analyzed using EthoVision XT 8.5 (Noldus Information Technology, The Netherlands) for differences in overall success in locating the food source and orienting parameters. Significant differences were found in the overall orientation ability of O. rusticus to locate an odor source when previously exposed to copper in combination with a source of pollution in the background of orientation trials. Crayfish exposed to copper in any capacity during the experiment (regardless of concentration or background during trials) showed slower walking speeds toward the source, decreased turning angles, increased heading angles toward the source, and decreased upstream heading angles. Results from this experiment support that copper impairs the ability of crayfish to detect, process, and/or respond appropriately to chemosensory

  10. The effects of bt corn on rusty crayfish (Orconectes rusticus) growth and survival.

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    Linn, Matthew D; Moore, Paul A

    2014-10-01

    Bt crops are one of the most commonly used genetically modified crops worldwide. Bt crops contain a gene that is derived from the bacteria Bacillus thuringiensis, which produces the Cry1Ab toxin. Bt corn that contains the Cry1Ab toxin is used throughout the Midwest United States to control crop pests such as the European corn borer (Ostrinia nubilalis). Headwater streams in regions known for intensive agriculture receive Bt corn detritus after the fall harvest, which is then consumed by a diverse community of stream invertebrates. The rusty crayfish (Orconectes rusticus) is a common invertebrate detritivore in these headwater streams. Both isogenic and Bt corn were grown under the controlled environmental conditions of a greenhouse and, after senescence, were tested for nutritional equality. Rusty crayfish were exposed to one of several detrital treatments composed of Bt corn, Bt corn plus American sycamore (Platanus occidentalis), isogenic corn alone, isogenic corn plus P. occidentalis, or P. occidentalis alone for 8 weeks. Both strains of corn were grown under the controlled environmental conditions in a greenhouse and were tested for nutritional equality after senescence. Crayfish were housed in live streams with a water temperature of 12.8 °C and a 12:12 h light-to-dark photoperiod. Survival and growth of animals within each experimental treatment were monitored each week. After 8 weeks of exposure, there was no statistically significant difference in growth between crayfish in Bt and isogenic treatments. However, survivorship was 31 % lower in the Bt treatment compared with the isogenic treatment. These results suggest that the Bt corn and isogenic corn were of equivalent nutritional value but that Bt corn does have a toxic effect on rusty crayfish during long-term exposure.

  11. Markers of oxidative stress in hepatopancreas of crayfish (Orconectes limosus, raf) experimentally exposed to nanosilver.

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    Strużyński, Witold; Dąbrowska-Bouta, Beata; Grygorowicz, Tomasz; Ziemińska, Elżbieta; Strużyńska, Lidia

    2014-11-01

    Silver nanoparticles, chemically neutral particles in the size range of 1-100 nm, express strong antimicrobial activity and therefore have a broad range of applications. The increased use of consumer products with nanosilver (nanoAg) may result in its release into the environment, and may particularly affect aquatic systems. The mechanisms of the harmful effects of nanoAg against aquatic organisms are unclear. Therefore, in the present study we investigate the pro-oxidative potential of these nanoparticles in experimentally exposed crayfish Orconectes limosus. Markers of oxidative stress and parameters of the antioxidant cell defense system such as total glutathione, glutathione reductase and the level of sulfhydryl groups were examined in the hepatopancreas of both sexes of O. limosus collected seasonally from Białe Lake (Poland) and subsequently exposed to nanoAg particles for 2 weeks. Exposure to nanoAg led to a high concentration-dependent increase in the rate of lipid peroxidation and a decrease of protein-bound SH groups which indicates protein oxidation. These markers of oxidative stress were accompanied by decreased levels of thiols and reduced activity of glutathione reductase. These results indicate a deficiency of reduced glutathione and suggest that the exposed organisms have less efficient antioxidative mechanisms available to counter ROS-mediated cellular stress. Furthermore, we find that confocal microscopy is of limited utility in monitoring the presence of silver nanoparticles in tissues of exposed crayfish. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  12. Glucose-6-Phosphate Dehydrogenase Regulation in Anoxia Tolerance of the Freshwater Crayfish Orconectes virilis

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    Benjamin Lant

    2011-01-01

    Full Text Available Glucose-6-phosphate dehydrogenase (G6PDH, the enzyme which catalyzes the rate determining step of the pentose phosphate pathway (PPP, controls the production of nucleotide precursor molecules (R5P and powerful reducing molecules (NADPH that support multiple biosynthetic functions, including antioxidant defense. G6PDH from hepatopancreas of the freshwater crayfish (Orconectes virilis showed distinct kinetic changes in response to 20 h anoxic exposure. Km values for both substrates decreased significantly in anoxic crayfish; Km NADP+ dropped from 0.015±0.008 mM to 0.012±0.008 mM, and Km G6P decreased from 0.13±0.02 mM to 0.08±0.007 mM. Two lines of evidence indicate that the mechanism involved is reversible phosphorylation. In vitro incubations that stimulated protein kinase or protein phosphatase action mimicked the effects on anoxia on Km values, whereas DEAE-Sephadex chromatography showed the presence of two enzyme forms (low- and high-phosphate whose proportions changed during anoxia. Incubation studies implicated protein kinase A and G in mediating the anoxia-responsive changes in G6PDH kinetic properties. In addition, the amount of G6PDH protein (measured by immunoblotting increased by ∼60% in anoxic hepatopancreas. Anoxia-induced phosphorylation of G6PDH could contribute to modifying carbon flow through the PPP under anoxic conditions, potentially maintaining NADPH supply for antioxidant defense during prolonged anoxia-induced hypometabolism.

  13. Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea

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    Simon, Olivier [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat., 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France)]. E-mail: olivier.simon@irsn.fr; Garnier-Laplace, Jacqueline [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat., 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France)

    2005-09-30

    At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9 {+-} 0.1 to 20.2 {+-} 9 {mu}g/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9 {+-} 0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution.

  14. Differences found in the macroinvertebrate community composition in the presence or absence of the invasive alien crayfish, Orconectes hylas

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    Freeland-Riggert, Brandye T.; Cairns, Stefan H.; Poulton, Barry C.; Riggert, Chris M.

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  15. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas.

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    Freeland-Riggert, Brandye T; Cairns, Stefan H; Poulton, Barry C; Riggert, Christopher M

    2016-01-01

    Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  16. Differences Found in the Macroinvertebrate Community Composition in the Presence or Absence of the Invasive Alien Crayfish, Orconectes hylas.

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    Brandye T Freeland-Riggert

    Full Text Available Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae, and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae. Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

  17. A successful crayfish invader is capable of facultative parthenogenesis: a novel reproductive mode in decapod crustaceans.

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    Miloš Buřič

    Full Text Available Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the "tens rule" which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group.

  18. A successful crayfish invader is capable of facultative parthenogenesis: a novel reproductive mode in decapod crustaceans.

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    Buřič, Miloš; Hulák, Martin; Kouba, Antonín; Petrusek, Adam; Kozák, Pavel

    2011-01-01

    Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the "tens rule" which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group.

  19. A Successful Crayfish Invader Is Capable of Facultative Parthenogenesis: A Novel Reproductive Mode in Decapod Crustaceans

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    Buřič, Miloš; Hulák, Martin; Kouba, Antonín

    2011-01-01

    Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the “tens rule” which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group. PMID:21655282

  20. The Impacts of flow alterations to crayfishes in Southeastern Oklahoma, with an emphasis on the mena crayfish (orconectes menae)

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    Brewer, Shannon K.; Dyer, Joseph J.

    2016-01-01

    Human activities can alter the environment to the point that it is unsuitable to the native species resulting in a loss of biodiversity. Ecologists understand the importance of biodiversity and the conservation of vulnerable species. Species that are narrowly endemic are considered to be particularly vulnerable because they often use specific habitats that are highly susceptible to human disturbance. The basic components of species conservation are 1) delineation of the spatial distribution of the species, 2) understanding how the species interacts with its environment, and 3) employing management strategies based on the ecology of the species. In this study, we investigated several crayfish species endemic to the Ouachita Mountains in Oklahoma and Arkansas. We established the spatial distributions (i.e., range) of the crayfish using Maximum Entropy species distribution modeling. We then investigated crayfish habitat use with quantitative sampling and a paired movement study. Finally, we evaluated the ability of crayfish to burrow under different environmental conditions in a controlled laboratory setting. Crayfish distribution at the landscape scale was largely driven by climate, geology and elevation. In general, the endemic crayfish in this study occurred above 300-m elevation where the geology was dominated by sandstone and shale, and rainfall totals were the highest compared to the rest of the study region. Our quantitative data indicated crayfish did not select for specific habitat types at the reach scale; however, crayfish appeared to continue to use shallow and dry habitat even as the streams dried. Movement by passive integrated transponder (PIT) tagged crayfish was highly variable but crayfish tended to burrow in response to drought rather than migrate to wet habitat. Controlled laboratory experiments revealed smaller substrate size (pebble) restricted crayfish burrowing more than larger substrates (cobble). We also found excess fine sediment restricted

  1. Toxicological studies of cadmium and zinc on the crayfish Orconectes virilis

    International Nuclear Information System (INIS)

    Mirenda, R.J.

    1985-01-01

    The acute toxicities of cadmium and of zinc to the crayfish Oronectes virilis were determined. Adult, intermolt crayfish were exposed to a series of concentrations of either cadmium or zinc for a two week period. Cadmium was found to be a cumulative poison to the crayfish; LC50 values decreased from 6.1 mg Cd/I for 96 hours to 0.7 mg Cd/I for two weeks. An incipient LC50 was also estimated to be 0.0604 mg Cd/I. Zinc was found to have a relatively low toxicity to O. virilis under the present exposure conditions. Whole animal and tissue analyses for cadmium or zinc were performed on the crayfish used in the acute toxicity tests. Whole animals concentrations both for cadmium and for zinc exhibited a linear relationship to exposure concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations of cadmium and zinc, and displayed a linear relationship to exposure concentrations (r = 0.82 and 0.87 respectively). The hepatopancreas displayed a plateau in metal concentrations and is probably the main storage site for both metals in the crayfish. The relationship of cadmium concentration to exposure concentration in the antennal glands also showed linearity (r = 0.65), while zinc levels reached a steady state level. All the remaining tissues analyzed exhibited a plateau in metal concentration

  2. A review of ecological interactions between crayfish and fish, indigenous and introduced

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    Reynolds J.D.

    2011-05-01

    Full Text Available Crayfish (decapods and fish are both long-lived large members of freshwater communities, often functioning as keystone species. This paper reviews interactions between these, with emphasis on the European context. Native crayfish and fish are in ecological balance, which may involve mutual predation, competition and sometimes habitat disturbance. This balance is disrupted by range extensions and translocations of native fish or crayfish into exotic situations. Some fish and crayfish have been translocated globally, chiefly from North America to other continents. Non-indigenous crayfish species (NICS may impact on native fish, just as introduced fish impact on indigenous crayfish species (ICS. Competition between ICS and NICS may result in making the former susceptible to various mechanisms of interaction with fish, indigenous or introduced. In Europe, long-established NICS – signals, spiny-cheek and red swamp crayfish – may occur in greater densities than ICS; they are more tolerant and aggressive and show more interactions with fish. More recent introductions, still restricted in distribution, have not yet received enough study for their impacts to be assessed. Interactions between fish and crayfish in North and South America, Madagascar and Australasia are also explored. Mechanisms of interaction between fish and crayfish include mutual predation, competition for food and spatial resources, food-web alteration and habitat modification. Resultant changes in communities and ecosystems may be physical or biotal, and affect both ecosystem services and exploitation potential.

  3. Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

    Science.gov (United States)

    Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

    2014-01-01

    Crayfishes and other freshwater aquatic fauna are particularly at risk globally due to anthropogenic demand, manipulation and exploitation of freshwater resources and yet are often understudied. The Ozark faunal region of Missouri and Arkansas harbours a high level of aquatic biological diversity, especially in regard to endemic crayfishes. Three such endemics, Orconectes eupunctus,Orconectes marchandi and Cambarus hubbsi, are threatened by limited natural distribution and the invasions of Orconectes neglectus.

  4. Fine structure of the spermatozoon in three species of Cambaridae (Arthropoda: Crustacea: Decapoda Cambarus robustus, Orconectes propinquus and Orconectes rusticus: a comparative biometrical study

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    Buket Yazicioglu

    2016-08-01

    Full Text Available The ultrastructure of spermatozoa in three species of cambarid crayfish, Cambarus robustus, Orconectes propinquus, and Orconectes rusticus, were studied and compared with eight previously studied species from different crayfish families using morphological features and biometrical data. The ultrastructure of spermatozoa show a generally conserved pattern including an acrosome and nucleus in the anterior and posterior parts of the cell, respectively, radial arms that wrap around the nucleus, and the whole cell is enclosed by an extracellular capsule. The most outstanding morphological feature in spermatozoa of three studied cambarid crayfish is the crest-like protrusions in the anterior part of the acrosome that can be used as one of the features for distinguishing the members of this family. Results of biometrical data reveal that acrosome size in the representatives of Parastacidae are the smallest, while representatives of Astacidae show the biggest acrosome. The acrosome size in species belonging to Cambaridae occupy an intermediate position between the two other families of freshwater crayfish. In conclusion, a combination of morphological features and biometrical data of spermatozoa can help distinguishing different species of the freshwater crayfish.

  5. Systematics and biogeography of Orconectes, subgenus Trisellescens, in the southeastern United States, a test of morphology-based classification

    Science.gov (United States)

    Christopher A. Taylor; Susan B. Adams; Guenter A. Schuster

    2014-01-01

    Diagnosable taxonomic units are fundamental to conservation biology and management of resources and the need for sound science in both fields is more pressing for aquatic ecosystems. Within freshwater crayfishes, the North American genus Orconectes is one of the most diverse in the World. Accurate assessments of species level relationships and species boundaries within...

  6. Impacts of drought and crayfish invasion on stream ecosystem structure and function

    Science.gov (United States)

    Magoulick, Daniel D.

    2014-01-01

    Drought and seasonal drying can be important disturbance events in many small streams, leading to intermittent or isolated habitats. Many small streams contain crayfish populations that are often keystone or dominant species in these systems. I conducted an experiment in stream mesocosms to examine the effects of drought and potential ecological redundancy of a native and invasive crayfish species. I examined the effects of drought (drought or control) and crayfish presence (none, native crayfish Orconectes eupunctus or invasive crayfish Orconectes neglectus) on stream mesocosm structure and function (leaf breakdown, community metabolism, periphyton, sediment and chironomid densities) in a fully factorial design. Each mesocosm contained a deep and shallow section, and drought treatments had surface water present (5-cm depth) in deep sections where tiles and leaf packs were placed. Drought and crayfish presence did not interact for any response variable. Drought significantly reduced leaf breakdown, and crayfish presence significantly increased leaf breakdown. However, the native and invasive crayfish species did not differ significantly in their effects on leaf breakdown. Drought significantly reduced primary production and community respiration overall, whereas crayfish presence did not significantly affect primary production and community respiration. Neither drought nor crayfish presence significantly affected periphyton overall. However, drought significantly reduced autotrophic index (AI), and crayfish presence increased AI. Inorganic sediment and chironomid density were not affected by drought, but both were significantly reduced by crayfish presence. O. eupunctus reduced AI and sediment more than O. neglectus did. Neither drought nor crayfish species significantly affected crayfish growth or survival. Drought can have strong effects on ecosystem function, but weaker effects on benthic structure. Crayfish can have strong effects on ecosystem

  7. Different aspects of reproduction strategies in crayfish: A review

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    Yazicioglu B.

    2016-01-01

    Full Text Available Study of the reproductive strategy of crayfish species is of great importance in the current astacological world. Crayfish are among the largest freshwater invertebrates, and as keystone species, they are able to regulate the structure of the benthic fauna in the freshwaters, demonstrating different ecological strategies and life spans ranging up to 20+ years. In order to bring together the various pieces of information related to this issue, this overview of published scientific reports was conducted. The majority of crayfish species studied show sexual dimorphism, with approximately equal numbers of males and females. However, over some decades numerous observations have been made for a few species that may have different modes of reproduction, such as hermaphroditism or intersex (e.g. Cherax quadricarinatus, Samastacus spinifrons, Parastacus virilastacus and Pacifastacus leniusculus and parthenogenesis (only Procambarus fallax f. virginalis. A recent study showed a new case of parthenogenesis as apomictic parthenogenesis (only Orconectes limosus. In addition, there are many investigations into the reproduction biology of crayfish, including using eyestalk ablation or androgenic gland ablation under various lab conditions and hybridization under natural conditions (e.g. Astacus astacus X Astacus leptodactylus, Orconectes rusticus X Orconectes propinquus. There are also some chemical factors which could possibly affect the reproduction system of crayfish in the wild.

  8. Invasive crayfish in the Pacific Northwest

    Science.gov (United States)

    Pearl, Christopher A.; McCreary, Brome; Adams, Michael

    2011-01-01

    Invasive species directly threaten freshwater biodiversity, particularly in regions of high aquatic richness like the Pacific Northwest (PNW). Crayfish are among the most impactful of aquatic invasive species. Invasive crayfish are considered ecosystem engineers due to their ability to alter basic wetland properties, such as reducing vegetation and bank integrity and increasing turbidity. In areas where invasion is advanced, crayfish pose major economic and ecological problems. Crayfish have been widely introduced for aquaculture and can become established in a wide range of habitat conditions. They also may be spread by anglers who use them as bait. Several non-native crayfish are established in the PNW, but the extent of their invasion is not well known. At least two groups are known from scattered sites in the PNW, and both have proven problematic for native species in other parts of the world: Red swamp crayfish (Procambarus clarkii) and several members of the genus Orconectes. Both groups are native to areas of the eastern United States. Both are identified globally as invasives of high concern and appear on the Oregon Department of Fish and Wildlife's "10 Most Unwanted" and the U.S. Forest Service's "Primary Species of Concern" lists for stream systems in the PNW. Despite the presence of introduced crayfish in the PNW and their high potential for negative effects, the scope of their invasion and effects on aquatic systems are not well known. The U.S. Geological Survey (USGS), along with local groups and state agencies, is working to clarify crayfish distribution and to outline which basins may not yet be invaded. Other goals are to improve understanding of habitat associations of invasive crayfish and their potential effects on native crayfish.

  9. Crayfish Use of Trash Versus Natural Cover in Incised, Sand-Bed Streams

    Science.gov (United States)

    Adams, Susan B.

    2014-02-01

    Historic land use changes and subsequent river channelization created deeply incised, unstable stream channels largely devoid of natural cover throughout the Yazoo River basin, Mississippi, USA. Large trash (e.g., televisions, toilets, car parts) dumped in streams provided shelter for some aquatic fauna. To determine whether trash served as a surrogate for natural cover, I examined crayfish use of both cover types. I sampled crayfishes by kick-seining 2 × 1-m plots in three cover classes: trash, natural cover, and no cover. I captured 415 crayfishes from 136 of the 294 plots. Most crayfishes were in natural cover (253), followed by trash (154), and no-cover (8) plots. Trash use varied by crayfish genus and size. Frequencies of all size classes of Procambarus and of the smallest Cambarus were higher in natural cover than trash. Many of the smallest individuals were found in live root mats. As Cambarus and Orconectes grew, they shifted more toward trash, and the largest Orconectes size class was significantly more abundant than expected in trash. Trash served as "artificial reefs," providing cover for crayfishes and other fauna, but functioned differently than the remaining natural cover. The results confirmed that stream substrate did not provide adequate instream cover for crayfishes in the study area and suggested that high-quality natural cover for large crayfishes was in short supply, at least for some species. Land management that provides for abundant, ongoing input and retention of complex cover, such as trees and live roots, to stream channels should be beneficial for crayfish assemblages.

  10. Identification of exotic North American crayfish in Europe by DNA barcoding

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    Filipová L.

    2011-05-01

    Full Text Available Several alien crayfish of North American origin have become established in Europe in recent decades, but their identification is often confusing. Our aim was to verify the taxonomic status of their European populations by DNA barcoding. We sequenced the cytochrome c oxidase subunit I (COI gene fragment of individuals representing all American crayfish known from European waters, and compared the results with reference sequences from North America. Our results confirm the morphological identification of Orconectes juvenilis from a population in eastern France, and of the marbled crayfish (Marmorkrebs, i.e., a parthenogenetic form of Procambarus fallax, from south-western Germany. Sequences of most individuals of presumed Procambarus acutus from the Netherlands were similar to American P. cf. acutus, but one was divergent, closer to a sequence of a reference individual of P. cf. zonangulus. However, divergences among three American P. cf. zonangulus samples were also high, comparable to interspecific variation within cambarid species complexes. The divergence between O. immunis from Europe and America also reached values corresponding to those observed among distinct Orconectes species. Genetic variation in the American range of these crayfish should therefore be further studied. Our study shows that DNA barcoding is useful for the rapid and accurate identification of exotic crayfish in Europe, and also provides insights into overall variation within these taxa.

  11. Effects of mining-derived metals on riffle-dwelling crayfish in southwestern Missouri and southeastern Kansas, USA

    Science.gov (United States)

    Allert, Ann L.; DiStefano, Robert J.; Schmitt, Christopher J.; Fairchild, James F.; Brumbaugh, William G.

    2012-01-01

    Riffle-dwelling crayfish populations were sampled at 16 sites in 4 tributaries of the Spring River located within the Tri-State Mining District in southwest Missouri. Crayfish density, physical habitat quality, and water quality were examined at each site to assess the ecological effects of mining-derived metals on crayfish. Metals (lead, zinc, and cadmium) were analyzed in samples of surface water, sediment, detritus, and whole crayfish. Sites were classified a posteriori into reference, mining, and downstream sites primarily based on metal concentrations in the materials analyzed. Three species of crayfish (Orconectes neglectus neglectus, O. macrus, and O. virilis) were collected during the study; however, only O. n. neglectus was collected at all sites. Mean crayfish densities were significantly lower at mining sites than at reference sites. Mean concentrations of metals were significantly correlated among the materials analyzed and were significantly greater at mining and downstream sites than at reference sites. Principal component analyses showed a separation of sites due to an inverse relationship among crayfish density, metals concentrations, and physical habitat quality variables. Sediment probable-effects quotients and surface-water toxic unit scores were significantly correlated; both indicated risk of toxicity to aquatic biota at several sites. Metals concentrations in whole crayfish at several sites exceeded concentrations known to be toxic to carnivorous wildlife. Mining-derived metals have the potential to impair ecosystem function through decreased organic matter processing and nutrient cycling in streams due to decreased crayfish densities.

  12. Effects of historical lead–zinc mining on riffle-dwelling benthic fish and crayfish in the Big River of southeastern Missouri, USA

    Science.gov (United States)

    Allert, A.L.; DiStefano, R.J.; Fairchild, J.F.; Schmitt, C.J.; McKee, M.J.; Girondo, J.A.; Brumbaugh, W.G.; May, T.W.

    2013-01-01

    The Big River (BGR) drains much of the Old Lead Belt mining district (OLB) in southeastern Missouri, USA, which was historically among the largest producers of lead–zinc (Pb–Zn) ore in the world. We sampled benthic fish and crayfish in riffle habitats at eight sites in the BGR and conducted 56-day in situ exposures to the woodland crayfish (Orconectes hylas) and golden crayfish (Orconectes luteus) in cages at four sites affected to differing degrees by mining. Densities of fish and crayfish, physical habitat and water quality, and the survival and growth of caged crayfish were examined at sites with no known upstream mining activities (i.e., reference sites) and at sites downstream of mining areas (i.e., mining and downstream sites). Lead, zinc, and cadmium were analyzed in surface and pore water, sediment, detritus, fish, crayfish, and other benthic macro-invertebrates. Metals concentrations in all materials analyzed were greater at mining and downstream sites than at reference sites. Ten species of fish and four species of crayfish were collected. Fish and crayfish densities were significantly greater at reference than mining or downstream sites, and densities were greater at downstream than mining sites. Survival of caged crayfish was significantly lower at mining sites than reference sites; downstream sites were not tested. Chronic toxic-unit scores and sediment probable effects quotients indicated significant risk of toxicity to fish and crayfish, and metals concentrations in crayfish were sufficiently high to represent a risk to wildlife at mining and downstream sites. Collectively, the results provided direct evidence that metals associated with historical mining activities in the OLB continue to affect aquatic life in the BGR.

  13. OCCURRENCE OF ALLOCHTHONOUS FRESHWATER CRAYFISHES IN LATIUM (CENTRAL ITALY

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    CHIESA S.

    2006-01-01

    Full Text Available The introduction of animal species, transfaunation and habitat destruction are among the greatest threats for biodiversity. In fact, in the water systems of Latium the occurrence of allochthonous crayfishes Procambarus clarkii, Orconectes limosus and Astacus leptodactylus has been observed. The distribution of these species in Latium highlighted some differences between them: Orconectes limosus and Astacus leptodactylus are present in restricted areas, while Procambarus clarkii has a wide distribution throughout the region. The present study confirmed their ecological plasticity, strong capability of invasion and adaptation to new environments of all three species, due to their rapid growth, utilisation of different trophic resources and the frequency and length of their reproduction periods. These aspects can cause irreversible ecologic and economic damage. The eradication of Procambarus clarkii would be a difficult task, because of its wide distribution and the many records of the species, especially in the Province of Latina, where complex field irrigation systems are found. All the agencies for environmental protection should increase control activities, with a serious field effort. As regards the other two species, eradication would be easier due to their limited distribution. It is important to avoid the spreading of these species; this can be done through public opinion awareness-raising campaigns and a continuous control on the region, increasing research and supporting it with new laws concerning the introduction and treatment of alien species.

  14. A comparison of two gears for quantifying abundance of lotic-dwelling crayfish

    Science.gov (United States)

    Williams, Kristi; Brewer, Shannon K.; Ellersieck, Mark R.

    2014-01-01

    Crayfish (saddlebacked crayfish, Orconectes medius) catch was compared using a kick seine applied two different ways with a 1-m2 quadrat sampler (with known efficiency and bias in riffles) from three small streams in the Missouri Ozarks. Triplicate samples (one of each technique) were taken from two creeks and one headwater stream (n=69 sites) over a two-year period. General linear mixed models showed the number of crayfish collected using the quadrat sampler was greater than the number collected using either of the two seine techniques. However, there was no significant interaction with gear suggesting year, stream size, and channel unit type did not relate to different catches of crayfish by gear type. Variation in catch among gears was similar, as was the proportion of young-of-year individuals across samples taken with different gears or techniques. Negative binomial linear regression provided the appropriate relation between the gears which allows correction factors to be applied, if necessary, to relate catches by the kick seine to those of the quadrat sampler. The kick seine appears to be a reasonable substitute to the quadrat sampler in these shallow streams, with the advantage of ease of use and shorter time required per sample.

  15. Do environmental changes or juvenile competition act as mechanisms of species displacement in crayfishes?

    Science.gov (United States)

    Westhoff, Jacob T.; DiStefano, R.J.; Magoulick, D.D.

    2012-01-01

    The Big Creek Crayfish, Orconectes peruncus, is native to the St. Francis River drainage in Missouri, USA and is often absent where the introduced Woodland Crayfish, Orconectes hylas, has established. We performed a field experiment to determine whether effects of current abiotic conditions and interspecific competition with O. hylas were responsible for displacement of O. peruncus from parts of their former range. We examined growth and survival of juvenile male O. peruncus exposed to juvenile male O. hylas in enclosures at two sites in the former range of O. peruncus. Enclosures contained 8 (low density) or 16 individuals (high density) and had O. peruncus only (control) or both species (interspecific treatment). Juvenile O. peruncus were able to survive and grow in portions of their former range, implicating biotic versus abiotic factors in the displacement of O. peruncus. Survival rates of O. peruncus did not differ among treatments at either site. Orconectes peruncus showed significant growth in all treatments and interspecific effects were not greater than intraspecific effects on O. peruncus growth rates. High-density treatments showed significantly reduced O. peruncus growth rates compared to low-density treatments, except in Carver Creek interspecific treatments. When considered in the context of previous studies examining the effects of O. hylas on O. peruncus, results suggest that neither direct competition between juvenile males of the two species or abiotic change are responsible for the decreased range of O. peruncus. Additional research is required to determine the mechanism(s) driving the displacement of O. peruncus. ?? 2011 Springer Science+Business Media B.V.

  16. Effects of predators on fish and crayfish survival in intermittent streams

    Science.gov (United States)

    Dekar, Matthew P.; Magoulick, Daniel D.

    2013-01-01

    Predation from aquatic and terrestrial predators arc important factors structuring the size and depth distribution of aquatic prey. We conducted mesocosm and tethering experiments on Little Mulberry Creek in northwest Arkansas during low flows to examine the effects of predators on fish and crayfish survival in intermittent streams Using shallow artificial pools (10 cm deep) and predator exclusions, we tested the hypothesis that large-bodied fish are at greater risk from terrestrial predators in shallow habitats compared to small-bodied individuals. Twenty-four circular pools (12 open top. 12 closed top) were stocked with two size classes of Campostoma anomalum (Central Stonerller) and deployed systematically in a single stream pool. In addition, we used a crayfish tethering experiment to test the hypothesis that the survival of small and large crayfish is greater in shallow and deep habitats, respectively. We tethered two size classes of Orconectes meeki meeki (Meek's Crayfish) along shallow and deep transects in two adjacent stream pools and measured survival for 15 days. During both experiments, we monitored the presence or absence of predators by visual observation and from scat surveys. We demonstrated a negative effect of terrestrial predators on Central Stonerller survival in the artificial pools, and larger individuals were more susceptible to predation. In contrast, small crayfish experienced low survival at all depths and large crayfish were preyed upon much less intensively during the tethering study, particularly in the pool with larger substrate. More studies are needed to understand how stream drying and environmental heterogeneity influence the complex interactions between predator and prey populations in intermittent streams.

  17. Bioenergetics assessment of fish and crayfish consumption by river otter (Lontra canadensis): integrating prey availability, diet, and field metabolic rate

    Science.gov (United States)

    Dekar, Matthew P.; Magoulick, Daniel D.; Beringer, J.

    2010-01-01

    River otters (Lontra canadensis) are important predators in aquatic ecosystems, but few studies quantify their prey consumption. We trapped crayfish monthly as an index of availability and collected otter scat for diet analysis in the Ozark Mountains of northwestern Arkansas, USA. We measured otter daily energy expenditure (DEE) with the doubly labeled water method to develop a bioenergetics model for estimating monthly prey consumption. Meek's crayfish (Orconectes meeki) catch-per-unit-effort was positively related to stream temperature, indicating that crayfish were more available during warmer months. The percentage frequency of occurrence for crayfish in scat samples peaked at 85.0% in summer and was lowest (42.3%) in winter. In contrast, the percentage occurrence of fish was 13.3% in summer and 57.7% in winter. Estimates of DEE averaged 4738 kJ·day-1 for an otter with a body mass of 7842 g. Total biomass consumption ranged from 35 079 to 52 653 g·month-1 (wet mass), corresponding to a high proportion of fish and crayfish in the diet, respectively. Otter consumption represents a large fraction of prey production, indicating potentially strong effects of otters on trophic dynamics in stream ecosystems.

  18. DISTRIBUTION AND REPRODUCTIVE BIOLOGY OF AUSTROPOTAMOBIUS TORRENTIUM IN BAVARIA AND DOCUMENTATION OF A CONTACT ZONE WITH THE ALIEN CRAYFISH PACIFASTACUS LENIUSCULUS

    Directory of Open Access Journals (Sweden)

    HUBER M. G.J.

    2005-07-01

    Full Text Available In Bavarian freshwater systems, the stone crayfish Austropotamobius torrentium is still present in many headwaters of Danubian tributaries. Since the 1960s an alien species, the signal crayfish Pacifastacus leniusculus, was introduced several times independently in Germany. Compared to the previously introduced Orconectes limosus, this species also invaded higher reaches of freshwater streams, thereby becoming a direct competitor of A. torrentium. In addition, it carried the crayfish plague, Aphanomyces astaci, which is lethal to European species. So far, there are only few documented populations of Pacifastacus leniusculus from upper streams in Bavaria and to our knowledge no reports of coexistence with the stone crayfish, which may be outcompeted by this much larger species due to direct interactions or reproductive superiority. In this study, we document the distribution of the stone crayfish in Bavaria and give evidence for a contact zone of Austropotamobius torrentium and apparently uninfected Pacifastacus leniusculus in the western Bavarian Forest, with a limited range of overlap and a slow upward displacement of the native species in the time frame of three years. Comparative studies of reproductive biology in the field and in the laboratory showed higher fecundity, faster juvenile growth and earlier hatching of the introduced species. These new aspects of the biology of the two involved species suggest an ecological superiority of P. leniusculus and may explain the long-term displacement of the native species, even in the absence of the crayfish plague Aphanomyces astaci.

  19. Crayfish impact desert river ecosystem function and litter-dwelling invertebrate communities through association with novel detrital resources.

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    Eric K Moody

    Full Text Available Shifts in plant species distributions due to global change are increasing the availability of novel resources in a variety of ecosystems worldwide. In semiarid riparian areas, hydric pioneer tree species are being replaced by drought-tolerant plant species as water availability decreases. Additionally, introduced omnivorous crayfish, which feed upon primary producers, allochthonous detritus, and benthic invertebrates, can impact communities at multiple levels through both direct and indirect effects mediated by drought-tolerant plants. We tested the impact of both virile crayfish (Orconectes virilis and litter type on benthic invertebrates and the effect of crayfish on detrital resources across a gradient of riparian vegetation drought-tolerance using field cages with leaf litter bags in the San Pedro River in Southeastern Arizona. Virile crayfish increased breakdown rate of novel drought-tolerant saltcedar (Tamarix ramosissima, but did not impact breakdown of drought-tolerant seepwillow (Baccharis salicifolia or hydric Fremont cottonwood (Populus fremontii and Gooding's willow (Salix goodingii. Effects on invertebrate diversity were observed at the litter bag scale, but no effects were found at the cage scale. Crayfish decreased alpha diversity of colonizing macroinvertebrates, but did not affect beta diversity. In contrast, the drought-tolerant litter treatment decreased beta diversity relative to hydric litter. As drought-tolerant species become more abundant in riparian zones, their litter will become a larger component of the organic matter budget of desert streams which may serve to homogenize the litter-dwelling community and support elevated populations of virile crayfish. Through impacts at multiple trophic levels, crayfish have a significant effect on desert stream ecosystems.

  20. Testing phylogenetic hypotheses of the subgenera of the freshwater crayfish genus Cambarus (Decapoda: Cambaridae.

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    Jesse W Breinholt

    Full Text Available The genus Cambarus is one of three most species rich crayfish genera in the Northern Hemisphere. The genus has its center of diversity in the Southern Appalachians of the United States and has been divided into 12 subgenera. Using Cambarus we test the correspondence of subgeneric designations based on morphology used in traditional crayfish taxonomy to the underlying evolutionary history for these crayfish. We further test for significant correlation and explanatory power of geographic distance, taxonomic model, and a habitat model to estimated phylogenetic distance with multiple variable regression.We use three mitochondrial and one nuclear gene regions to estimate the phylogenetic relationships for species within the genus Cambarus and test evolutionary hypotheses of relationships and associated morphological and biogeographical hypotheses. Our resulting phylogeny indicates that the genus Cambarus is polyphyletic, however we fail to reject the monophyly of Cambarus with a topology test. The majority of the Cambarus subgenera are rejected as monophyletic, suggesting the morphological characters used to define those taxa are subject to convergent evolution. While we found incongruence between taxonomy and estimated phylogenetic relationships, a multiple model regression analysis indicates that taxonomy had more explanatory power of genetic relationships than either habitat or geographic distance.We find convergent evolution has impacted the morphological features used to delimit Cambarus subgenera. Studies of the crayfish genus Orconectes have shown gonopod morphology used to delimit subgenera is also affected by convergent evolution. This suggests that morphological diagnoses based on traditional crayfish taxonomy might be confounded by convergent evolution across the cambarids and has little utility in diagnosing relationships or defining natural groups. We further suggest that convergent morphological evolution appears to be a common

  1. Habitat and co-occurrence of native and invasive crayfish in the Pacific Northwest, USA

    Science.gov (United States)

    Pearl, Christopher A.; Adams, Michael J.; McCreary, Brome

    2013-01-01

    Biological invasions can have dramatic effects on freshwater ecosystems and introduced crayfish can be particularly impacting. We document crayfish distribution in three large hydrographic basins (Rogue, Umpqua, Willamette/Columbia) in the Pacific Northwest USA. We used occupancy analyses to investigate habitat relationships and evidence for displacement of native Pacifastacus leniusculus (Dana, 1852) by two invaders. We found invasive Procambarus clarkii (Girard, 1852), in 51 of 283 sites and in all three hydrographic basins. We found invasive Orconectes n. neglectus (Faxon, 1885) at 68% of sites in the Rogue basin and provide first documentation of their broad distribution in the Umpqua basin. We found P. clarkii in both lentic and lotic habitats, and it was positively associated with manmade sites. P. leniusculus was positively associated with lotic habitats and negatively related to manmade sites. In the Rogue and Umpqua basins, O. n. neglectus and P. leniusculus were similar in their habitat associations. We did not find a negative relationship in site occupancy between O. n. neglectus and P. leniusculus. Our data suggest that P. clarkii has potential to locally displace P. leniusculus. There is still time for preventive measures to limit the spread of the invasive crayfish in this region.

  2. The Sensitivity of the Crayfish Reward System to Mammalian Drugs of Abuse

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    Adam T. Shipley

    2017-12-01

    Full Text Available The idea that addiction occurs when the brain is not able to differentiate whether specific reward circuits were triggered by adaptive natural rewards or falsely activated by addictive drugs exist in several models of drug addiction. The suitability of crayfish (Orconectes rusticus for drug addiction research arises from developmental variation of growth, life span, reproduction, behavior and some quantitative traits, especially among isogenic mates reared in the same environment. This broad spectrum of traits makes it easier to analyze the effect of mammalian drugs of abuse in shaping behavioral phenotype. Moreover, the broad behavioral repertoire allows the investigation of self-reinforcing circuitries involving appetitive and exploratory motor behavior, while the step-wise alteration of the phenotype by metamorphosis allows accurate longitudinal analysis of different behavioral states. This paper reviews a series of recent experimental findings that evidence the suitability of crayfish as an invertebrate model system for the study of drug addiction. Results from these studies reveal that unconditioned exposure to mammalian drugs of abuse produces a variety of stereotyped behaviors. Moreover, if presented in the context of novelty, drugs directly stimulate exploration and appetitive motor patterns along with molecular processes for drug conditioned reward. Findings from these studies indicate the existence of drug sensitive circuitry in crayfish that facilitates exploratory behavior and appetitive motor patterns via increased incentive salience of environmental stimuli or by increasing exploratory motor patterns. This work demonstrates the potential of crayfish as a model system for research into the neural mechanisms of addiction, by contributing an evolutionary, comparative context to our understanding of natural reward as an important life-sustaining process.

  3. The distribution of the crayfishes Orconectes limosus (Rafinesque) and Astacus astacus (L.) (Crustacea, Decapoda) in the Netherlands

    NARCIS (Netherlands)

    Geelen, J.F.M.

    1978-01-01

    INTRODUCTION According to Holthuis (1950a) the family Astacidae is represented in the Netherlands only by one species, Astacus astacus (L., 1758). Apart from a detailed description of the external anatomy, he gave the following data. The average size of the adults amounts to 80 mm, however, the

  4. Effect of uranium chronic exposure on the moult in crayfish

    International Nuclear Information System (INIS)

    Simon, O.; Camilleri, V.; Garnier-Laplace, J.

    2004-01-01

    Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

  5. Effect of uranium chronic exposure on the moult in crayfish

    Energy Technology Data Exchange (ETDEWEB)

    Simon, O.; Camilleri, V.; Garnier-Laplace, J. [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

    Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

  6. Crayfish-Bambara Groundnut W

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    days with Nutrend (a commercial weaning food used as reference diet) and processed sweet potato-crayfish- soyabean/bambara ... The results obtained with diet 3 (sweat potato – bambara groundnut mixture) and diet 5 (sweat potato – soya bean mixture) ..... sensitivities of muscle (e.g. heart muscle) and liver tissues to the ...

  7. The effects of sublethal levels of 2,4-dichlorophenoxyacetic acid herbicide (2,4-D) on feeding behaviors of the crayfish O. rusticus.

    Science.gov (United States)

    Browne, Amanda M; Moore, Paul A

    2014-08-01

    The widespread use of herbicides across the globe has increased the probability of synthetic chemicals entering freshwater habitats. On entering aquatic habitats, these chemicals target and disrupt both physiological and behavioral functioning in various aquatic organisms. Herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D), can have negative impacts on chemoreception because these receptor cells are in direct contact with water-soluble chemicals in the environment. Studies focusing on lethal concentration (LC50) levels may understate the impact of herbicides within aquatic habitats because damage to the chemoreceptors can result in modified behaviors or lack of appropriate responses to environmental or social cues. The purpose of this experiment was to determine whether exposure to sublethal levels of 2,4-D alters the foraging behaviors of crayfish Orconectes rusticus. We hypothesized that crayfish exposed to greater concentrations of 2,4-D would be less successful in locating food or on locating food would consume smaller amounts possibly due to an inability to recognize the food odors in the contaminated waters. Crayfish were exposed to three sublethal levels of 2,4-D for 96 h and placed into a Y-maze system with a fish gelatin food source placed randomly in the right or left arm. Average walking speed, average time spent in the correct arm, and percent consumption were analyzed. Our data show that crayfish were impaired in their ability to forage effectively. These inabilities to locate and consume adequate amounts of food could result in lower body weights and decreased fitness in populations of crayfish exposed to 2,4-D in natural habitats.

  8. Comparing macrophyte herbivory by introduced Louisiana crayfish ...

    African Journals Online (AJOL)

    Comparing macrophyte herbivory by introduced Louisiana crayfish ( Procambarus clarkii ) (Crustacea: Cambaridae) and native Dytiscid beetles ( Cybister tripunctatus ) (Coleoptera: Dytiscidae), in Kenya.

  9. Freshwater Crayfish: A Potential Benthic-Zone Indicator of Nanosilver and Ionic Silver Pollution.

    Science.gov (United States)

    Brittle, Seth W; Paluri, Sesha L A; Foose, Daniel P; Ruis, Matthew T; Amato, Matthew T; Lam, Nhi H; Buttigieg, Bryan; Gagnon, Zofia E; Sizemore, Ioana E

    2016-07-05

    Nowadays, silver nanoparticles (AgNPs) are utilized in numerous applications, raising justified concerns about their release into the environment. This study demonstrates the potential to use freshwater crayfish as a benthic-zone indicator of nanosilver and ionic silver pollution. Crayfish were acclimated to 20 L aquaria filled with Hudson River water (HRW) and exposed for 14 days to widely used Creighton AgNPs and Ag(+) at doses of up to 360 μg L(-1) to surpass regulated water concentrations. The uptake and distribution of Ag in over 650 exoskeletons, gills, hepatopancreas and muscles samples were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES) in conjunction with two complementary U.S. EPA-endorsed methods: the external calibration and the standard additions. Reflecting the environmental plasticity of the two investigated species, Orconectes virilis accumulated in a dose-dependent manner more Ag than Procambarus clarkii (on average 31% more Ag). Both species showed DNA damage and severe histological changes in the presence of Ag. However, Ag(+) generally led to higher Ag accumulations (28%) and was more toxic. By the harvest day, about 14 ± 9% of the 360 μg L(-1) of AgNP exposure in the HRW oxidized to Ag(+) and may have contributed to the observed toxicities and bioaccumulations. The hepatopancreas (1.5-17.4 μg of Ag g(-1) of tissue) was identified as the best tissue-indicator of AgNP pollution, while the gills (4.5-22.0 μg g(-1)) and hepatopancreas (2.5-16.7 μg g(-1)) complementarily monitored the presence of Ag(+).

  10. REINTRODUCTION OF NOBLE CRAYFISH ASTACUS ASTACUS AFTER CRAYFISH PLAGUE IN NORWAY

    Directory of Open Access Journals (Sweden)

    TAUGBØL T.

    2004-01-01

    Full Text Available The Glomma and Halden watercourses in Norway were hit by crayfish plague in 1987 and 1989. Reintroduction of the noble crayfish started in 1989 in the Glomma and in 1995 in the Halden watercourse. Norway has especially good conditions for reintroduction of the native crayfish after crayfish plague, as there is no alien plague-carrying crayfish species in the country. In the Glomma watercourse, approx. 15 000 adult crayfish and 10 000 juveniles have been stocked while in the Halden watercourse the figures are 19 000 adults and 26 500 juveniles. All stocking sites were previously regarded as very good crayfish localities. Four years after stocking, natural recruitment was recorded at all adult crayfish stocking sites in the Glomma watercourse and at most sites in the Halden watercourse. Current crayfish density is, however, much lower than pre-plague densities even at the sites where population development has been in progress for more than 10 years. Extensive post-stocking movements were recorded among adult crayfish. Some sites seemed more suitable for settling, resulting in a great variation in CPUE between the different test-fishing sites. Juveniles seem more appropriate as stocking material if the goal is to re-establish a population in a particular area, due to their stationary behaviour, which seems to remain as they grow larger.

  11. Garden ponds as potential introduction pathway of ornamental crayfish

    Directory of Open Access Journals (Sweden)

    Patoka J.

    2014-01-01

    Full Text Available The private stocking of ornamental crayfish in garden ponds was discussed in previous studies, but there is a lack of detailed analysis for better understanding of this introduction pathway. The Czech Republic is one of leading EU countries in trade with ornamental crayfish and private garden ponds are popular among people. The crayfish keepers in the country were interviewed by self-administered questionnaire to gather data about principal characteristics of the keepers and detailed information about crayfish breeding that are of interest for conservation managers. Besides of releasing crayfish into garden ponds, alarming illegal behavior such as releasing of juvenile crayfish into the wild, and capturing of indigenous crayfish from wild populations, were registered. Therefore focusing on public education to increase awareness of possible unwanted consequences of crayfish release and introduction of an obligation to inform customers about hazardousness of non-indigenous crayfish species for retailers and wholesalers is recommended.

  12. Freshwater crayfish invasions in South Africa: past, present and ...

    African Journals Online (AJOL)

    Freshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims to indicate which areas are at risk from invasion.

  13. The influence of coarse-scale environmental features on current and predicted future distributions of narrow-range endemic crayfish populations

    Science.gov (United States)

    Dyer, Joseph J.; Brewer, Shannon K.; Worthington, Thomas A.; Bergey, Elizabeth A.

    2013-01-01

    1.A major limitation to effective management of narrow-range crayfish populations is the paucity of information on the spatial distribution of crayfish species and a general understanding of the interacting environmental variables that drive current and future potential distributional patterns. 2.Maximum Entropy Species Distribution Modeling Software (MaxEnt) was used to predict the current and future potential distributions of four endemic crayfish species in the Ouachita Mountains. Current distributions were modelled using climate, geology, soils, land use, landform and flow variables thought to be important to lotic crayfish. Potential changes in the distribution were forecast by using models trained on current conditions and projecting onto the landscape predicted under climate-change scenarios. 3.The modelled distribution of the four species closely resembled the perceived distribution of each species but also predicted populations in streams and catchments where they had not previously been collected. Soils, elevation and winter precipitation and temperature most strongly related to current distributions and represented 6587% of the predictive power of the models. Model accuracy was high for all models, and model predictions of new populations were verified through additional field sampling. 4.Current models created using two spatial resolutions (1 and 4.5km2) showed that fine-resolution data more accurately represented current distributions. For three of the four species, the 1-km2 resolution models resulted in more conservative predictions. However, the modelled distributional extent of Orconectes leptogonopodus was similar regardless of data resolution. Field validations indicated 1-km2 resolution models were more accurate than 4.5-km2 resolution models. 5.Future projected (4.5-km2 resolution models) model distributions indicated three of the four endemic species would have truncated ranges with low occurrence probabilities under the low-emission scenario

  14. [A new method of therapy for branchiobdellosis in crayfish].

    Science.gov (United States)

    Lohniský, K

    1979-02-01

    Crayfish (Astacus fluviatilis Fabricius, 1793) were treated three times with a bath of diluted ammonia water and proflavine for four and six minutes at a temperature of 18 degrees C to get rid of the ectoparasitic worms of Branchiobdella parasita Henle, 1835; the hatching ability of the Branchiobdella parasita eggs was stopped after the treatment. No lethal effect of the bath on the crayfish of 5 to 14 cm was observed, the lethal effect on the young crayfish borne on the uropods of the female crayfish cannot be eliminated: during the baths the young crayfish died (the death rate was approximately 6% of the average fertility of crayfish); the young crayfish may have been damaged during the treatment operations with the crayfish. The bath of diluted ammonia water and proflavine may be recommended for the treatment of branchiobdellosis in crayfish to be planted, or after several-hour storage of crayfish supplied to the market. One replication of the above cycle is sufficient according to the results obtained. The ammonia content in the ammonia water depends also on the duration of storage and on the storage temperature--it can drop during the storage. Therefore the ammonia water should be used as soon as possible after the despatchment from the place of production; the ammonia content should be determined by means of titration before preparing the bath, and according to this content the dilution ratio should be adjusted.

  15. Status and management of noble crayfish Astacus astacus in Estonia

    Directory of Open Access Journals (Sweden)

    T. Paaver

    2009-01-01

    Full Text Available Noble crayfish Astacus astacus (L. is an indigenous and the only crayfish species in Estonia. It is potentially endangered by invasion of alien species, diseases and habitat deterioration but does not have legal protected status and is fished only for recreational purpose. Crayfish Working Group of Ministry of Environment and Department of Aquaculture of the Estonian University of Life Sciences have developed crayfish conservation and management plan. Since 1994 standardized test fishing with traps (which catch only crayfish over 7 cm TL has been carried out and database of these fishings shows, that crayfish is dwelling in more than 255 sites in the lakes, rivers, streams, artificial reservoirs. In 52% of monitored sites populations are weak, catch per trap night is below 1 specimen. Exceptionally rich is the stock on the island Saaremaa, where in 59% of populations catch per trap night is over 4 and can reach 50. Licensed recreational catch is allowed in regions, where monitoring data show good status of crayfish stock. It is not allowed to sell the crayfish caught on recreational license. Crayfishing season is limited with August, size limit in recreational fishery is 11 cm TL. There are 10 operating crayfish farms and 15 are under construction. The farms produce yearly around 1000 kg of commercial size crayfish for export to Finland. Over 200000 juveniles are produced for restocking yearly. Restocking projects e.g. restoration of populations, which have been lost because of plague have been successful. The main threat factor is crayfish plague. In 2006–2007 it destroyed the stock of crayfish farms of companies Veteko, Pähkla, Astacus and wild population of Põduste river on the island Saaremaa.

  16. Exponential increase of signal crayfish in running waters in Sweden – due to illegal introductions?

    Directory of Open Access Journals (Sweden)

    Bohman P.

    2011-07-01

    Full Text Available Sweden has only one indigenous species of crayfish, the noble crayfish (Astacus astacus, Fabricius. There has been a steady decline of noble crayfish populations in Sweden since 1907, mainly due to the crayfish plague. To substitute the noble crayfish fishery lost, the Swedish government launched a large-scale introduction of the signal crayfish (Pacifastacus leniusculus Dana. Today, the signal crayfish is regarded as a chronic carrier of the crayfish plague, and an expansion of the species may seriously threaten the noble crayfish. This paper examines the decrease of noble crayfish populations, and the concurrent expansion of signal crayfish in running waters. Data from the Swedish Electrofishing RegiSter (SERS was used. We found that in 1980–1984 the noble crayfish occurred in 4.5% of the studied river sections. In 2008–2009 the occurrences had decreased to 1.9%. In contrast, the signal crayfish had increased in occurrence, from 0.2% (1980–1984 to 11.8% in (2008–2009. We studied the number of stocking permits for signal crayfish introductions, and the available signal crayfish population from the open fishery in Lake Vättern, as possible causes of this expansion. A negative correlation between stocking permits and increased occurrence in streams, and a positive correlation between the availability of crayfish in Lake Vättern and the occurrence in streams was found. This suggests that the expansion of signal crayfish may be due to illegal introductions, further endangering the endemic noble crayfish.

  17. Louisiana crayfish ( Procambarus clarkii ) (Crustacea: Cambaridae ...

    African Journals Online (AJOL)

    In an eight-week laboratory mesocosm experiment, crayfish decreased water clarity and reduced populations of slow-moving, benthic invertebrates including non-target snails, chironomid larvae and oligochaetes. Similar declines in invertebrates occurred in an unreplicated 35-day whole-pond experiment. In addition, water ...

  18. Response of crayfish to hyporheic water availability and excess sedimentation

    Science.gov (United States)

    Dyer, Joseph J.; Worthington, Thomas A.; Brewer, Shannon K.

    2015-01-01

    Crayfish in many headwater streams regularly cope with seasonal drought. However, it is unclear how landscape changes affect the long-term persistence of crayfish populations. We designed two laboratory experiments to investigate the acute effects of common landscape stressors on crayfish: water withdrawal and sedimentation. The first experiment tested the interaction among water withdrawals (four 24-h water reductions of 0, 15, 30, or 45 cm) and two substrate treatments (pebble and cobble) on the burrowing depth of crayfish. The second experiment evaluated the effects of excess fine sediment (three treatments of 0, 45, and 90% sediment) and substrate type (cobble and pebble) on crayfish burrowing depth. Crayfish were able to burrow deeper into the simulated hyporheic zone in cobble substrate when compared to pebble. Crayfish subjected to greater water withdrawals in the pebble treatment were not able to reach the simulated hyporheic zone. Excess fine sediment reduced the depth that crayfish burrowed, regardless of substrate type. Results from this study suggest excess fine sediment may reduce crayfish persistence, particularly when seeking refuge during prolonged dry conditions.

  19. SHELTER COMPETITION BETWEEN TWO INVASIVE CRAYFISH SPECIES: A LABORATORY STUDY

    Directory of Open Access Journals (Sweden)

    ALONSO F.

    2006-01-01

    Full Text Available Alien crayfishes represent a common threat to aquatic ecosystems. Their spread in Europe is leading to more frequent contacts between different invasive species populations. Shelter can be an important factor in the resulting interactions. A laboratory experiment was designed to analyse the competition for shelter in similarly sized males of two species that show an invasive behaviour in Spain, Pacifastacus leniusculus and Procambarus clarkii. We carried out 24 heterospecific, six-hour trials, with 30 min behavioural observations per hour. Most often, red swamp crayfish were both the first (70.8% and the long-term winner (62.5%. Usually, the long-term winner was the first winner. Whenever shelter was occupied, a passive behaviour by unsheltered individuals was more frequent in signal crayfish than in red swamp crayfish. When both were unsheltered, signal crayfish displayed more often a passive behaviour. Although the observed behaviour might be explained as the result of dominance by the red swamp crayfish over the signal crayfish, shelter availability and class, as well as different growth patterns and population size structures, could change the intensity and the outcome of the encounters in the wild, where signal crayfish usually reach larger sizes than red swamp crayfish.

  20. Monitoring of noble, signal and narrow-clawed crayfish using environmental DNA from freshwater samples

    DEFF Research Database (Denmark)

    Agersnap, Sune; Larsen, William Brenner; Knudsen, Steen Wilhelm

    2017-01-01

    human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities. Knowledge about crayfish distribution...

  1. Parasites of crayfish ( P. clarki ) and lobsters ( Macrobrachium ...

    African Journals Online (AJOL)

    Studies on parasites of crayfish and lobsters as indicators of metal pollution in Great Kwa River, Nigeria was evaluated using appropriate instruments for determination of Physicochemical parameters and detection of metals. Formol ether centrifugation method was used for isolation of parasites. A total of 150 crayfish and ...

  2. A new ostracod (Entocytheridae, Notocytherinae) on New Guinea crayfish1)

    NARCIS (Netherlands)

    Hart, D.G.; Hart, C.W.

    1970-01-01

    In 1967 we examined the crayfish collections in the Rijksmuseum van Natuurlijke Historie, Leiden, to determine if the crayfishes collected in New Guinea in 1954 by Dr. L. B. Holthuis, Dr. L. D. Brongersma, and Dr. M. Boeseman (Boeseman, 1963) were hosts to commensal ostracods. Of the collections

  3. parasites of crayfish (p. clarki) and lobsters (macrobrachium

    African Journals Online (AJOL)

    PROF. BARTH EKWEME

    Studies on parasites of crayfish and lobsters as indicators of metal pollution in Great Kwa River, Nigeria was evaluated using appropriate instruments for determination of Physicochemical parameters and detection of metals. Formol ether centrifugation method was used for isolation of parasites. A total of 150 crayfish and ...

  4. MINIMISING LOSS OF CRAYFISH AND HABITATDURING WORKS ON WATERCOURSES

    Directory of Open Access Journals (Sweden)

    PEAY S.

    2003-04-01

    Full Text Available Works in watercourses with white-clawed crayfish Austropotamobius pallipes cause temporary or permanent loss of habitat and crayfish. Past modifications can also leave waterbodies unfavourable for crayfish, but sometimes there is scope to improve them. Mitigation measures can reduce the impact and reinstate or even improve habitat. Various case studies show measures used during engineering works and some of the problems. Good planning and supervision are vital. The big issues at river and catchment scales (non-indigenous crayfish, disease, water quality and landuse may be higher priorities than provision of habitat at site or reach level; e.g. fencing in pastures improves riparian areas for crayfish and other species. If necessary, there are various options for natural and artificial refuges, but their success depends on flow characteristics, substrate and accessibility. Microhabitat can make the difference between success and failure.

  5. Practical disinfection chemicals for fishing and crayfishing gear against crayfish plague transfer

    Directory of Open Access Journals (Sweden)

    Jussila J.

    2014-01-01

    Full Text Available We tested four commercial disinfectants against crayfish plague (Aphanomyces astaci spores in both aquatic solutions and with material mimicking fishing and crayfishing gear, e.g. traps, ropes, mesh, etc. The tested disinfectants were Proxitane®5:14, Proxitane®12:20, Wofasteril®E400, Virkon®S and hydrogen peroxide. The effects of the chemicals were initially tested in liquid zoospore cultures and the effective concentrations were then further tested using clean and dirty model materials (PP sheet, nylon rope, cotton fabric contaminated with A. astaci spore solutions. The disinfectants effective against infective crayfish plague spores with both clean and dirty model materials were Proxinate®5:14 (effective concentration was 30 mg·L-1 of PAA and Virkon®S (3 g·L-1, while Proxinate®12:20 (10 mg·L-1 of PAA and Wofasteril®E400 (30 mg·L-1 of PAA worked only with clean model materials. Hydrogen peroxide was not effective in the tested concentrations and conditions. Based on the results, the disinfectants most suitable for the fishing and crayfishing gear disinfection would be Proxitane®5:14 and Virkon®S, with the condition that all the gear should be thoroughly cleaned of organic matter to ensure inactivation of A. astaci spores.

  6. Salinity tolerance of marbled crayfish Procambarus fallax f. virginalis

    Directory of Open Access Journals (Sweden)

    Veselý Lukáš

    2017-01-01

    Full Text Available Eastern Europe comprises a significant part of the native ranges for indigenous crayfish species (ICS belonging to the genus Astacus. This region has been largely overlooked by astacologists and considered relatively immune to the impacts of non-indigenous crayfish species (NICS. The recent discovery of two marbled crayfish Procambarus fallax f. virginalis populations in Ukraine has changed this view. Increased propagule pressure (mainly due to pet trade has raised concerns of NICS which may negatively impair the ecosystems of Azov, Black and Caspian Seas and their tributaries inhabited by ICS. In this study, we provide the first insight into salinity tolerance of marbled crayfish. We performed a 155-day experiment using 5 different salinities (6, 9, 12, 15, and 18 ppt and a freshwater control. Evaluation of survival, growth and reproduction suggests that marbled crayfish have a lower salinity tolerance than other crayfish species, which may limit their invasive potential in brackish environments. However, its ability to survive for more than 80 days at 18 ppt opens up the possibility of gradual dispersion and adaptation to brackish conditions. Our study highlights the need for further studies elucidating the potential for marbled crayfish to negatively impair these ecosystems.

  7. DISTRIBUTION OF CRAYFISH IN EUROPE AND SOME ADJOINING COUNTRIES

    Directory of Open Access Journals (Sweden)

    HOLDICH D. M.

    2002-07-01

    Full Text Available The distribution of crayfish in Europe is examined using information from a variety of sources mainly for the last two decades. All European countries have at least one indigenous crayfish species (ICS, many with large stocks, and most countries in Western Europe have at least one non-indigenous crayfish species (NICS. Some species termed indigenous in certain countries may have been introduced in relatively recent times. However, the meaning of the term indigenous (native varies between countries. NICS continue to expand their ranges and present a continued threat to ICS through competition and transmission of diseases, notably crayfish plague. The current high level of interest in crayfish means that many countries are monitoring their crayfish situation and, where necessary, taking steps to renew stocks of threatened indigenous species, some of which are apparently on the verge of extinction. A more regular monitoring programme for European crayfish as a whole is needed if the demise of indigenous species is to be prevented.

  8. Current conservation strategies for European crayfish

    Directory of Open Access Journals (Sweden)

    Kozák P.

    2011-05-01

    Full Text Available A round table discussion involving 25 researchers from 11 European countries was organized during the congress “European Crayfish: food, flagships and ecosystem services” (held in Poitiers, France, 26–29th October 2010 to consider current activities dealing with management of indigenous crayfish species (ICS with special regards to their culture, restocking and conservation strategy. In the following opinion paper, we attempt to summarize best practice of current conservation strategy as well as advantages and disadvantages of applied tools and approaches for listed species or species complexes. The development of conceptual models for the protection of ICS in Europe seems to be necessary; however, currently recommended approaches of conservation strategy of ICS differ according to countries and species. The different approaches to conservation of Astacus astacus and species in the genus Austropotamobius, such as genetic diversity, captive breeding, origin and characteristics of stocking material and establishment, as well as long-term objectives of sanctuary or “ark” sites, were highlighted during the round table discussion.

  9. Okefenokee National Wildlife Refuge Crayfish Survey (Pilot Study)

    Data.gov (United States)

    Department of the Interior — Okefenokee’s crayfish fauna has received limited attention by American astacologists. This document represents the first report of a multiyear effort to document the...

  10. Harmful impact of filamentous algae (Spirogyra sp.) on juvenile crayfish

    OpenAIRE

    Ulikowski Dariusz; Chybowski Łucjan; Traczuk Piotr

    2015-01-01

    The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch.), in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 ...

  11. The potential for using red claw crayfish and hybrid African catfish as ...

    African Journals Online (AJOL)

    The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After 15 days, both crayfish and ...

  12. BIOCIDE TREATMENT OF PONDS IN SCOTLAND TO ERADICATE SIGNAL CRAYFISH

    Directory of Open Access Journals (Sweden)

    PEAY S.

    2006-01-01

    Full Text Available This trial aimed to eradicate illegally introduced signal crayfish Pacifastacus leniusculus in the North Esk catchment, Scotland. Sites treated were (1 an isolated gravel-pit (c. 9,000 m3, with crayfish present for 6 years; (2 three dammed ponds, (c. 5,000 m3 and (3 a leaking, offline pond (c. 6,000 m3, with crayfish for two years. Preliminary toxicity tests with substrate present indicated doses. Treatment at sites (1 and (2 (in October 2004, water temperature 13°C comprised deoxygenation with sodium sulphite to stimulate emergence, then application of natural pyrethrum (Pyblast. Exposed margins were sprayed with Pyblast to prevent escapes. Crayfish mortality was high, but one survivor was seen after 5 days. Pyblast was applied from a tank with Na2SO3 residue, which subsequent investigation indicated reduced Pyblast below the target 0.1 mg l-1. Site (1 was re-treated (end October, target 0.15 mg l-1 Pyblast, no Na2SO3, 9°C. Mortality was confirmed using caged crayfish. Prior to treatment at site (2, throughflow was stopped and fish removed. Biomonitoring was carried out with freshwater shrimps Gammarus in the adjacent watercourse. Treatment of site (3 (December, target 0.2 mg l-1, 4°C necessitated continuous back-pumping of leakage for a 2-week recovery period to avoid contamination of the river downstream. Caged crayfish took up to 5 days for 100% mortality. No crayfish were found in a summer survey after the treatments with Pyblast alone, but were caught in the ponds with Na2SO3 pre-treatment. Monitoring is required for 2-5 years.

  13. Harmful impact of filamentous algae (Spirogyra sp. on juvenile crayfish

    Directory of Open Access Journals (Sweden)

    Ulikowski Dariusz

    2015-12-01

    Full Text Available The aim of this study was to determine the impact of filamentous algae on the growth and survival of juvenile narrow-clawed crayfish, Astacus leptodactylus (Esch., in rearing basins. Three stocking variants were used: A - basins with a layer of filamentous algae without imitation mineral substrate; B - basins with a layer of filamentous algae with imitation mineral substrate; C - basins without filamentous algae but with mineral substrate. The crayfish were reared from June 12 to October 10 under natural thermal conditions and fed a commercial feed. The results indicated that the presence of the filamentous algae did not have a statistically significant impact on the growth of the juvenile crayfish (P > 0.05. The presence of the filamentous algae had a strong negative impact on juvenile crayfish survival and stock biomass (P < 0.05. The layer of gravel and small stones that imitated the mineral substrate of natural aquatic basins somewhat neutralized the disadvantageous impact the filamentous algae had on the crayfish.

  14. Infection Status of Freshwater Crabs and Crayfish with Metacercariae of Paragonimus westermani in Korea

    Science.gov (United States)

    Kim, Eun-Min; Kim, Jae-Lip; Choi, Sung-Il; Lee, Soon-Hyung

    2009-01-01

    The present study investigated the infection status of Paragonimus westermani metacercariae in freshwater crabs (n = 363) and crayfish (n = 31) from October 2007 to October 2008 using the crush method. All of the freshwater crabs, Eriocheir japonicus, were negative for P. westermani metacercariae while 10 (32.3%) of the 31 examined crayfish were positive. The 10 positive crayfish were caught in Haenam, Jeollanam-do, and there were 8-59 (mean 28.4) metacrcariae per infected crayfish. These results suggest that P. westermani metacerariae are still transmitted by crayfish enzootically in southern Korea, and that freshwater crabs may transmit metacercariae only on rare occasions. PMID:19967096

  15. REVIEW OF THE NATIONAL RESTOCKING PROGRAMME “ACTIVE PROTECTION OF NATIVE CRAYFISH IN POLAND” 1999-2001

    OpenAIRE

    ŠMIETANA P.; KRZYWOSZ T.; STRUŻYŃSKI W.

    2004-01-01

    After the first spread of crayfish plague (aphanomycosis) at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of ...

  16. The marbled crayfish as a paradigm for saltational speciation by autopolyploidy and parthenogenesis in animals

    Directory of Open Access Journals (Sweden)

    Günter Vogt

    2015-11-01

    Full Text Available The parthenogenetic all-female marbled crayfish is a novel research model and potent invader of freshwater ecosystems. It is a triploid descendant of the sexually reproducing slough crayfish, Procambarus fallax, but its taxonomic status has remained unsettled. By cross-breeding experiments and parentage analysis we show here that marbled crayfish and P. fallax are reproductively separated. Both crayfish copulate readily, suggesting that the reproductive barrier is set at the cytogenetic rather than the behavioural level. Analysis of complete mitochondrial genomes of marbled crayfish from laboratory lineages and wild populations demonstrates genetic identity and indicates a single origin. Flow cytometric comparison of DNA contents of haemocytes and analysis of nuclear microsatellite loci confirm triploidy and suggest autopolyploidisation as its cause. Global DNA methylation is significantly reduced in marbled crayfish implying the involvement of molecular epigenetic mechanisms in its origination. Morphologically, both crayfish are very similar but growth and fecundity are considerably larger in marbled crayfish, making it a different animal with superior fitness. These data and the high probability of a divergent future evolution of the marbled crayfish and P. fallax clusters suggest that marbled crayfish should be considered as an independent asexual species. Our findings also establish the P. fallax–marbled crayfish pair as a novel paradigm for rare chromosomal speciation by autopolyploidy and parthenogenesis in animals and for saltational evolution in general.

  17. Expansion of the marbled crayfish in Slovakia: beginning of an invasion in the Danube catchment?

    Directory of Open Access Journals (Sweden)

    Boris Lipták

    2016-01-01

    Full Text Available The marbled crayfish, Procambarus fallax f. virginalis, is a taxon widely available in the aquarium pet trade, which has been introduced to open waters in several European countries and in Madagascar. Recent studies confirmed this parthenogenetically reproducing crayfish as a high-risk invasive species, and vector of the crayfish plague pathogen, Aphanomyces astaci. It has been first discovered in Slovakia in 2010, but the status of the local population was not studied since then. Due to enlarged sampling area around the first report and one locality, where we presupposed the crayfish occurrence, we identified new marbled crayfish populations. Here, we report presence of three newly established marbled crayfish populations in Slovakia. Two populations are located critically close to the Váh River, a major tributary of the Danube River; one of them being directly connected to the Váh River via a side channel during occasional floods. The third established marbled crayfish population was found at the mouth of a thermal stream flowing into the Nitra River, a tributary of the Váh River. In this stream, crayfish coexist with other exotic fish and gastropod species of aquarium origin. We presume that the reported localities may serve as a source for further expansion of the marbled crayfish in the mid-part of the Danube catchment. Floods, active dispersal (including overland, passive dispersal by zoochory or anthropogenic translocations are among the major drivers facilitating the marbled crayfish colonization. We have not detected the crayfish plague pathogen in any of the studied populations. However, if spreading further, the marbled crayfish will encounter established populations of crayfish plague carriers in the Danube River, in which case they may acquire the pathogen by horizontal transmission and contribute to spread of this disease to indigenous European crayfish species.

  18. Observations of crayfish plague infections in commercially important narrow-clawed crayfish populations in Turkey

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    Kokko Harri

    2018-01-01

    Full Text Available We studied the presence of possible Aphanomyces astaci infections in eight Turkish narrow-clawed crayfish (Astacus leptodactylus populations by analyzing the prevalence and genotypes of the disease agent A. astaci. The qPCR analyses revealed A. astaci infection in seven of the studied eight populations, with the agent level A2 or higher. The agent levels among the infected populations varied from A0 to A5, i.e., from negative to high level of infection, based on qPCR ranking. Based on the sequencing of the chitinase gene and the mitochondrial ribosomal rnnS and rnnL subunits, we detected both A (As and B (PsI haplogroups of A. astaci in our samples, with each of the studied populations being carriers of only one haplotype. The results confirm previous detections of A. astaci in Turkish narrow-clawed crayfish populations and reveal, that both A and B haplogroup A. astaci carriers exist widely in A. leptodactylus populations of Turkey.

  19. FEEDING PREFERENCES OF THE INVASIVE CRAYFISH, PROCAMBARUS CLARKII

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    Gherardi Francesca

    2007-10-01

    Full Text Available This laboratory study analyzes feeding preferences of a crayfish species with high invasive potentials, the red swamp crayfish Procambarus clarkii. We first conducted a series of multiple-choice tests among fresh plants (3 tests, one per each of three seasons, i.e. spring, summer, and autumn and animals (1 test in summer. In the first tests, crayfish were simultaneously offered fresh pieces of seven plants of different growth forms and taxonomic groups, selected on the basis of their availability in the habitat. In the second test, the offered animals were dead earthworms, rainbow trout fry, and toad tadpoles. Then, a binary choice test was run in autumn between the most preferred plant (Urtica sp. and earthworms. The percentages of organic C and N contents were measured for each food category using a gas-chromatography technique and the assimilation efficiency of both dry mass and organic content was assessed in a dedicated experiment. The results showed that P. clarkii is selective when offered fresh plants, consuming a relatively larger biomass of Urtica (in the three seasons examined, green algae (in spring, and Polygonum (in summer and autumn. Surprisingly, crayfish did not exhibit preference for any animal prey. Also, P. clarkii’s feeding decisions seemed not to be associated with either the availability of plants in the habitat or their occurrence in the gut contents of wild crayfish. Neither did their ingested biomass depend on the organic content or assimilation efficiency. Procambarus clarkii preferred Urtica sp. over earthworms, notwithstanding the higher nutritional value and assimilation efficiency of the latter. The above results might suggest that feeding preferences of the species often depend on factors other than nutritional value and digestibility. Future studies will analyze all the possible factors together in order to unravel the rules that govern feeding preferences in crayfish. In the case of invasive species, such

  20. Interactions between accumulated copper, bacterial community structure and histamine levels in crayfish meat during storage.

    Science.gov (United States)

    Soedarini, Bernadeta; van Gestel, Cornelis A M; van Straalen, Nico M; Widianarko, Budi; Röling, Wilfred F M

    2014-08-01

    Pollution in aquaculture areas may negatively impact edible species and threaten seafood quality and safety. The aim of this study was to determine the interaction between copper and bacteria in the aquatic habitat and their impact upon crustaceans. Marbled crayfish was chosen as a model of aquatic crustaceans and the influence of metal contamination on bacterial community structure in water used to culture crayfish and in crayfish themselves was investigated. Histamine, an allergen commonly formed by certain groups of bacteria in crustacean edible tissue during storage, was also determined. Copper exposure increased its concentration in crayfish meat by 17.4%, but the copper concentration remained within acceptable food safety limits. Elevated copper levels affected the bacterial community both in the water used to cultivate crayfish and in the marbled crayfish themselves. Cluster analysis of 16S rRNA-gene based microbial community fingerprints revealed that copper impacted the bacterial community in the water and in the crayfish meat. However, copper exposure reduced the formation of histamine in crayfish meat during storage by 66.3%. Copper from the habitat appears to reduce histamine accumulation in crayfish meat during storage by affecting the bacterial community structure of the cultivation water and most likely also in the intestine of the crayfish. From a food safety point of view, copper treatment during the aqua culturing of crustaceans has a positive impact on the postharvest stage. © 2013 Society of Chemical Industry.

  1. Potential impacts of alien freshwater crayfish in South Africa | de ...

    African Journals Online (AJOL)

    The habitat preferences and life history characteristics of four alien species of freshwater crayfish (Cherax tenuimanus, C. destructor, C. quadricarinatus and Procambarus clarkii) are reviewed. The potential impact of these species on South African freshwater ecosystems is assessed and the desirability of allowing their ...

  2. Short Note Invasive Australian crayfish Cherax quadricarinatus in ...

    African Journals Online (AJOL)

    Most crayfish were between 50 and 59.9 mm carapace length. Males (average 82.6 g) were significantly heavier than females (37.2 g) and males were larger in carapace length, carapace width, chela length and chela width. A feral population of C. quadricarinatus is now established in the Sanyati Basin. Possible modes of ...

  3. Crayfish Behavior: Observing Arthropods to Learn about Science & Scientific Inquiry

    Science.gov (United States)

    Rop, Charles J.

    2010-01-01

    This is a set of animal behavior investigations in which students will practice scientific inquiry as they observe crayfish, ask questions, and discuss territoriality, social interactions, and other behaviors. In doing this, they hone their skills of observation, learn to record and analyze data, control for variables, write hypotheses, make…

  4. Natural crayfish clone as emerging model for various biological ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 36; Issue 2. Marmorkrebs: Natural crayfish clone as emerging model for various biological disciplines. Günter Vogt. Mini-review Volume 36 Issue 2 June 2011 pp 377-382. Fulltext. Click here to view fulltext PDF. Permanent link:

  5. Conservation status of crayfishes of the United States and Canada

    Science.gov (United States)

    Christopher A. Taylor; Melvin L. Warren; J. F. Fitzpatrick; Horton H. Hobbs; Raymond F. Jezerinac; William L. Pflieger; Henry W. Robinson

    1996-01-01

    The American Fisheries Society (AFS) Endangered Species Committee herein provides a list of all crayfishes (families and Cambaridae) in the United States and Canada that includes state provincial distributions; a comprehensive review of the conservation status of all taxa; and references on biology, conservation, and...

  6. Phylogenetic species delimitation for crayfishes of the genus Pacifastacus.

    Science.gov (United States)

    Larson, Eric R; Castelin, Magalie; Williams, Bronwyn W; Olden, Julian D; Abbott, Cathryn L

    2016-01-01

    Molecular genetic approaches are playing an increasing role in conservation science by identifying biodiversity that may not be evident by morphology-based taxonomy and systematics. So-called cryptic species are particularly prevalent in freshwater environments, where isolation of dispersal-limited species, such as crayfishes, within dendritic river networks often gives rise to high intra- and inter-specific genetic divergence. We apply here a multi-gene molecular approach to investigate relationships among extant species of the crayfish genus Pacifastacus, representing the first comprehensive phylogenetic study of this taxonomic group. Importantly, Pacifastacus includes both the widely invasive signal crayfish Pacifastacus leniusculus, as well as several species of conservation concern like the Shasta crayfish Pacifastacus fortis. Our analysis used 83 individuals sampled across the four extant Pacifastacus species (omitting the extinct Pacifastacus nigrescens), representing the known taxonomic diversity and geographic distributions within this genus as comprehensively as possible. We reconstructed phylogenetic trees from mitochondrial (16S, COI) and nuclear genes (GAPDH), both separately and using a combined or concatenated dataset, and performed several species delimitation analyses (PTP, ABGD, GMYC) on the COI phylogeny to propose Primary Species Hypotheses (PSHs) within the genus. All phylogenies recovered the genus Pacifastacus as monophyletic, within which we identified a range of six to 21 PSHs; more abundant PSHs delimitations from GMYC and ABGD were always nested within PSHs delimited by the more conservative PTP method. Pacifastacus leniusculus included the majority of PSHs and was not monophyletic relative to the other Pacifastacus species considered. Several of these highly distinct P. leniusculus PSHs likely require urgent conservation attention. Our results identify research needs and conservation priorities for Pacifastacus crayfishes in western

  7. Double blow: Alien crayfish infected with invasive temnocephalan in South African waters

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    Louis du Preez

    2013-09-01

    Full Text Available Trade in live, freshwater crayfish for ornamental markets, as well as for aquaculture, has grown rapidly and has become the major pathway for the introduction of non-indigenous crayfish species to several countries worldwide. Here we report on the first record of the Australian "redclaw" Cherax quadracarinatus in the natural waters of a game reserve in South Africa. To compound the situation, these redclaw crayfish were infected with a non-indigenous temnocephalan flatworm parasite. Both crayfish and temnocephalan were in full breeding condition, with young. Further spreading of this crayfish to the subtropical, water-rich, northern KwaZulu-Natal Province of South Africa and southern Mozambique is predicted. Not only might the crayfish compete with indigenous aquatic invertebrates but the non-host-specific temnocephalan might transfer to local decapods, such as freshwater crabs.

  8. UNDERSTANDING AND MANAGING BIODIVERSITY IN RELATION TO NATIVE CRAYFISH POPULATIONS IN EUROPE

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    GHERARDI F.

    2003-04-01

    Full Text Available The loss or diminution of European crayfish populations because of both habitat deterioration and competition with alien crayfish – also responsible for the dissemination of the crayfish plague – would reduce the biodiversity at the species level. The topic “What is meant by biodiversity?” in the context of native freshwater crayfish in Europe was discussed during the Kilkenny CRAYNET meeting in order to make the point about the varied meanings of biodiversity from genes and individuals to population levels.

  9. Effects of climate change, invasive species, and disease on the distribution of native European crayfishes.

    Science.gov (United States)

    Capinha, César; Larson, Eric R; Tricarico, Elena; Olden, Julian D; Gherardi, Francesca

    2013-08-01

    Climate change will require species to adapt to new conditions or follow preferred climates to higher latitudes or elevations, but many dispersal-limited freshwater species may be unable to move due to barriers imposed by watershed boundaries. In addition, invasive nonnative species may expand into new regions under future climate conditions and contribute to the decline of native species. We evaluated future distributions for the threatened European crayfish fauna in response to climate change, watershed boundaries, and the spread of invasive crayfishes, which transmit the crayfish plague, a lethal disease for native European crayfishes. We used climate projections from general circulation models and statistical models based on Mahalanobis distance to predict climate-suitable regions for native and invasive crayfishes in the middle and at the end of the 21st century. We identified these suitable regions as accessible or inaccessible on the basis of major watershed boundaries and present occurrences and evaluated potential future overlap with 3 invasive North American crayfishes. Climate-suitable areas decreased for native crayfishes by 19% to 72%, and the majority of future suitable areas for most of these species were inaccessible relative to native and current distributions. Overlap with invasive crayfish plague-transmitting species was predicted to increase. Some native crayfish species (e.g., noble crayfish [Astacus astacus]) had no future refugia that were unsuitable for the modeled nonnative species. Our results emphasize the importance of preventing additional introductions and spread of invasive crayfishes in Europe to minimize interactions between the multiple stressors of climate change and invasive species, while suggesting candidate regions for the debatable management option of assisted colonization. © 2013 Society for Conservation Biology.

  10. MANAGEMENT STRATEGIES, YIELD AND POPULATION DEVELOPMENT OF THE NOBLE CRAYFISH ASTACUS ASTACUS IN LAKE STEINSFJORDEN

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    SKURDAL J.

    2002-07-01

    Full Text Available Lake Steinsfjorden is the most important noble crayfish locality in Norway. The crayfish population has been monitored annually since 1979 including data on total trapping effort, yield and population composition before and after the catching season. The harvest has ranged from 0.7-4.7 kg.ha-1. The catch per trap night decreased prior to 1991 and the yield was reduced by some 50% over the years 1987-1992 as compared to 1979-1986. This was due to removal of small crayfish, high exploitation and the establishment of dense stands of Canadian pondweed (Elodea canadensis. Baited traps catch a large fraction of crayfish < 95 mm total length minimum size. These should according to the regulations immediately be released into the lake. However, it is apparent from the size composition that release of these small crayfish was rather incomplete. In 1983, trap mesh size was increased from 17.5 mm to 21 mm to reduce the fraction of undersized crayfish in the trap catches, yet no effects of this increased mesh size on crayfish size distribution were observed. The legal season has been reduced three times during the study period. In 1983, the closing date was changed from 31 December to 15 September. In 1989 the legal season was further reduced to two weeks and finally in 1995 to 10 days. This reduced total trap effort by 45%. The shorter season allow many crayfish to moult twice instead of once between seasons and the fraction of large crayfish has thus increased and so has the catch per trap night. Canadian pondweed has established dense annual stands and thus has made large parts of the shallow areas unsuitable for crayfish, causing an overall decrease in crayfish population size and production.

  11. Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

    Energy Technology Data Exchange (ETDEWEB)

    Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

    1979-01-01

    The White Oak floodplain was contaminated with several radionuclides, including /sup 239/Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using /sup 237/Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the /sup 237/Pu was associated with the body tissues. Complementary data for /sup 237/Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of /sup 239/Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average /sup 239/Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of /sup 239/Pu in the soil in which they burrow and was found to be eight orders of magnitude less.

  12. Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

    International Nuclear Information System (INIS)

    Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

    1979-01-01

    The White Oak floodplain was contaminated with several radionuclides, including 239 Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using 237 Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the 237 Pu was associated with the body tissues. Complementary data for 237 Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of 239 Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average 239 Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of 239 Pu in the soil in which they burrow and was found to be eight orders of magnitude less

  13. ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

    Science.gov (United States)

    In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

  14. Chronic effects of arsenic on American red crayfish, Procambarus clarkii, exposed to monosodium methanearsonate (MSMA) herbicide

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, S.M. (Southern Univ., Baton Rouge, LA (USA)); Flagge, C.T. (Bay De Noc Community College, Escanaba, MI (USA))

    1990-07-01

    Bioaccumulative and biomagnifying effects of arsenic on crayfish have been reported. However, no work has been done on the chronic effects of this heavy metal on crayfish populations. There is a great concern for MSMA (Monosodium Methanearsonate) herbicide in the vicinity of natural waters due to its high water solubility and bioaccumulative potential. American red crayfish (Procambarus clarkii) account for 98% of the annual crayfish harvest in North America. Those pesticides which have greater water solubility (i.e. MSMA) than other less soluble compounds may cause higher mortalities of aquatic organisms, or cause adverse chronic effects if the non-target animals are sublethally exposed. This work was conducted in the laboratory to assess the possible chronic effects of arsenic on crayfish.

  15. Monitoring of noble, signal and narrow-clawed crayfish using environmental DNA from freshwater samples.

    Directory of Open Access Journals (Sweden)

    Sune Agersnap

    Full Text Available For several hundred years freshwater crayfish (Crustacea-Decapoda-Astacidea have played an important ecological, cultural and culinary role in Scandinavia. However, many native populations of noble crayfish Astacus astacus have faced major declines during the last century, largely resulting from human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities. Knowledge about crayfish distribution and early detection of non-indigenous and invasive species are crucial elements in successful conservation of indigenous crayfish. The use of environmental DNA (eDNA extracted from water samples is a promising new tool for early and non-invasive detection of species in aquatic environments. In the present study, we have developed and tested quantitative PCR (qPCR assays for species-specific detection and quantification of the three above mentioned crayfish species on the basis of mitochondrial cytochrome oxidase 1 (mtDNA-CO1, including separate assays for two clades of A. leptodactylus. The limit of detection (LOD was experimentally established as 5 copies/PCR with two different approaches, and the limit of quantification (LOQ were determined to 5 and 10 copies/PCR, respectively, depending on chosen approach. The assays detected crayfish in natural freshwater ecosystems with known populations of all three species, and show promising potentials for future monitoring of A. astacus, P. leniusculus and A. leptodactylus. However, the assays need further validation with data 1 comparing traditional and eDNA based estimates of abundance, and 2 representing a broader geographical range for the involved crayfish species.

  16. Signal crayfish as zoogeomorphic agents: diel patterns of fine sediment suspension in a crayfish-affected river and the implications for fine sediment fluxes and dynamics

    Science.gov (United States)

    Rice, Stephen; Johnson, Matthew; Reeds, Jake; Longstaff, Holly; Extence, Chris

    2013-04-01

    The signal crayfish (Pacifasticus leniusculus) is a formidable invasive species that has had a deleterious impact on native freshwater fauna across Europe. We contend that the impact of this animal extends beyond ecology into geomorphology and hypothesise that crayfish are significant agents of fine sediment recruitment and mobilisation, with potentially profound impacts on water quality, substrate quality and fine sediment fluxes. Building on pioneering work by colleagues at Queen Mary University, London this poster considers the role of crayfish in fine sediment suspension in a lowland, gravel-bed river. The hypothesis that nocturnal increases in crayfish activity are associated with a greater frequency of sediment suspension events and increases in ambient turbidity, is tested. Strong diel fluctuations in water turbidity were recorded at several sites on the Brampton Arm of the River Nene in England, a river heavily populated by signal crayfish, during August and September 2012. With the exception of three summer flood events, stage measurements during the same period were essentially flat, ruling out a hydraulic cause for overnight rises in turbidity. Water samples collected at midnight and at midday at one site confirm this diel pattern for suspended sediment concentration. Higher mean turbidity values overnight are associated with an increase in the magnitude and frequency of isolated turbidity spikes or events and this is consistent with crayfish nocturnalism. In particular, we suspect that turbidity events are caused by the construction and maintenenance of burrows and by interactions between crayfish and the river bed while foraging, fighting and avoiding each other. Tying the diel SSC signal directly to crayfish activity proved difficult, but several lines of argument presented here suggest that crayfish are the most likely cause of the diel pattern. These results provide substantial support for the idea that signal crayfish are important zoogeomorphic

  17. THE FRESHWATER CRAYFISH AUSTROPOTAMOBIUS PALLIPESIN SOUTH TYROL: HERITAGE SPECIES AND BIOINDICATOR

    Directory of Open Access Journals (Sweden)

    FÜREDER L.

    2003-04-01

    Full Text Available Rapid decline of crayfish in European freshwaters and continuing threat necessitate integrated actions in conservation and management of native crayfish populations. Besides biological reasons (diseases, plague, the impact of toxic and harmful substances (fertilisers, herbicides or wastewater effluents, habitat alteration or fragmentation have been responsible for their decline in some regions. The same is true for the region of South Tyrol, where compared to previous investigations, only 10 of a former total of 15 crayfish locations in the water bodies could be affirmed. Although two new populations of the non-indigenous Astacus astacus were detected, the native Austropotamobius pallipes continues to decline. While many investigations have focused accurately on causal coherences for the decline of native populations, the properties of crayfish facilitate to reverse the situation. In a few examples, the potential of Austropotamobius pallipes, the native crayfish in South Tyrol, as “surrogate species” for effective biological conservation is discussed. Given the various adequate attributes of freshwater crayfish as surrogate species (including indicator species, umbrella species and flagship species qualities, they may help to advance not only the crayfish situation itself but also freshwater ecosystem properties in general.

  18. Annelid symbiont assemblage and European stone crayfish − a deterministic relationship with implications for conservation management

    Directory of Open Access Journals (Sweden)

    Berger Christian

    2017-01-01

    Full Text Available The protected European stone crayfish, Austropotamobius torrentium, is a host to epibionts inhabiting its exoskeleton. Despite evidence of the close association of these epibionts to the crayfish and the beneficial services provided for the crayfish, the main factors influencing their occurrence, distribution and abundance are still poorly understood. In order to investigate the stone crayfish epibiont community, the ecological requirements of individual species, and aspects of the host-epibiont relationship we collected data at several crayfish populations in Austria, Switzerland and Germany. At each location, we recorded the epibiont position on the crayfish host along with a number of biotic and abiotic parameters. Apart from recording the Branchiobdella species B. parasita, B. hexadonta, B. pentadonta and B. balcanica, we detected for the first time the polychaete Hystricosoma chappuisi in the European Alps. Species-specific biogeographical and habitat factors such as river catchment borders, crayfish length, water temperature and nutrients concentration were identified to be important for the occurrence and abundance of epibionts. Branchiobdella species were strongly linked to certain host body areas, providing evidence for the existence of different functional traits within the annelid assemblage. With this study we demonstrate that the crayfish–epibionts relationship includes structural and functional complexities that can be important for defining management units in future conservation policies. Due to benefits for the mutualistic relationship, restocking and reintroduction actions are likely to be more successful, if ecological requirements of both the host and the epibiont species are considered.

  19. Continental-wide distribution of crayfish species in Europe: update and maps

    Directory of Open Access Journals (Sweden)

    Kouba A.

    2014-01-01

    Full Text Available Recently published astacological studies substantially improved available data on distribution of crayfish in various European regions. At the same time, spread of invasive species has been recorded, additional non-indigenous species became established in various countries, and losses of populations of native species due to crayfish plague and other negative factors were observed. We overview recent advances in this knowledge, and provide updated colour maps of the distribution of all crayfish species present in Europe. These maps are originally based on the data from the Atlas of Crayfish in Europe published in 2006 as a result of the CRAYNET project, and were further updated from more recently published reports, grey literature, and especially thanks to contributions and feedback of over 70 specialists from 32 countries. Separate maps are available for all indigenous crayfish species in Europe as well as for three most widespread non-indigenous crayfish species. Additionally, two maps give locations of known findings of crayfish species introduced to Europe after 1980. These newly established alien species have so far restricted distributions; however, the frequency of recent reports suggests that findings of such species resulting from releases of aquarium pets will further increase.

  20. Are the effects of an invasive crayfish on lake littoral macroinvertebrate communities consistent over time?

    Directory of Open Access Journals (Sweden)

    Ruokonen T. J.

    2016-01-01

    Full Text Available Management of invasive species requires assessment of their effects on recipient ecosystems. However, impact assessment of invasive species commonly lacks a long-term perspective which can potentially lead to false conclusions. We examined the effects of the invasive signal crayfish (Pacifastacus leniusculus Dana on the stony littoral macroinvertebrate communities of a large boreal lake and assessed the extent to which the patterns observed in previous short-term studies were stable over time. We used temporal macroinvertebrate data collected in five consecutive years from a site with a well-established crayfish population, a site with no crayfish and a site where crayfish had been recently introduced. Our results revealed that signal crayfish had temporally rather consistent negative effects on the benthic macroinvertebrate assemblages but that the effects might be limited to certain taxa, in particular Gastropoda and Coleoptera. We also observed increases in Gastropoda density and taxa richness following a decline in crayfish density, indicating that the recovery of invertebrate assemblages might be fast. Hence, negative effects on benthic macroinvertebrates can likely be minimized by effective control of the signal crayfish population.

  1. WHITE-CLAWED CRAYFISH IN MUDDY HABITATS: MONITORING THE POPULATION IN THE RIVER IVEL, BEDFORDSHIRE, UK

    Directory of Open Access Journals (Sweden)

    PEAY S.

    2006-01-01

    Full Text Available White-clawed crayfish Austropotamobius pallipes are usually associated with stony substrates, tree roots, or refuges in submerged banks. The River Ivel has the last known population of white-clawed crayfish in Bedfordshire. Prior to 2005, much of the bed comprised uniform silt, plus leaf-litter. Stands of reedmace Typha latifolia and other emergent vegetation were localised in less shaded areas. Initial survey results suggested a population at low abundance. A low-cost monitoring strategy was started in 2001 and continued three times a year to 2005, using engineering bricks, which offer artificial refuges. Crayfish are counted when bricks are lifted periodically. De-silting of c. 430 m river was carried out in February 2005, to improve habitat and to maintain the flood capacity in the channel upstream of a mill weir. Additional bricks were deployed a few weeks in advance of de-silting, then bricks and crayfish were lifted prior to dredging and were returned the next day. Starting upstream, soft, wet mud was dredged out, placed on the bank and searched manually for crayfish. Banks, tree roots and shallow margins were left undisturbed. In all, 4,142 crayfish were found in dredgings from a 430 m length of the mid channel. Crayfish were strongly associated with emergent vegetation, but many were present below the surface of the silt. Crayfish released in the dredged channel immediately burrowed into the silt retained on the channel margins. Monitoring after dredging showed no change in abundance in the main area with in-bank refuges and lots of bricks, but there was an increase in occupancy of bricks in an area where most crayfish had been in emergent vegetation.

  2. Status of the white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858, in Spain : distribution and legislation

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    ALONSO F.

    2000-01-01

    Full Text Available The white-clawed crayfish, Austropotamobius pallipes, is the only native species of freshwater crayfish in Spain. This species sustained a first-magnitude inland fishery up to the end of 1970's, when the crayfish plague struck the Spanish waters. It is detected an overall loss of distribution area of populations inhabiting the medium and lower reaches of the main river catchments, especially in Southern and Central Spain. The number of surviving populations can be estimated in ca. 700. Remaining native crayfish populations currently inhabit marginal areas. The populations are very fragmented, occupy short stretches, and are frequently isolated from the main river system. The current distribution is the result of a sum of different factors, i.e. crayfish plague, habitat alterations, extreme climatic drought, etc. The incidence and relative importance of each one varied during the last 15 years, with crayfish plague being a predominant negative factor in the seventies and eighties, and climatic drought in the nineties. The current trend of disappearance is a sufficient reason to consider the native crayfish as at risk of extinction. However neither the national legislation nor most of the regional government legislations have listed this species as endangered. An analysis of the legislation dealing with freshwater crayfish in Spain shows : (a an uneven and generally low level of protection given to the native species and (b a very complex fishing and commercialization regulations for crayfish that show significant changes from one region to another. This complex legislation, complemented with a general lack of data on crayfish populations, low levels of management and public involvement, and different strategies in regional governments regarding restocking programs with exotic species, makes a confusing situation. In order to decrease the general tendency of regression of A. pallipes a conservation program for this species needs to be implemented

  3. Towards a sustainable human use of freshwater crayfish (Crustacea, Decapoda, Astacidea

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    Gherardi F.

    2011-07-01

    Full Text Available To face the severe loss in biodiversity recorded in freshwater crayfish (Crustacea, Decapoda, Astacidea, there is an increasing awareness that the CBD’s concept of the sustainable use of natural resources should be applied also to this large assemblage of species. This review paper will synthesize the several uses we make or have made of crayfish with the purpose of pinpointing where sustainability is desirable and feasible. Uses are here classified as direct (i.e. consumption and production and indirect. The latter uses refer to the recreational, cultural, ethical, aesthetic, scientific and education values of crayfish. An additional indirect use regards the environmental key role this taxon plays. Several examples, mostly related to Europe, will be provided to illustrate the importance of crayfish to human societies, culture and history. The potential of assigning a non-use value to them will be finally discussed.

  4. ROUNDTABLE SESSION 3: PHYLOGENY OF EUROPEAN CRAYFISH – IMPROVING THE TAXONOMY OF EUROPEAN CRAYFISH FOR A BETTER CONSERVATION

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    SCHULZ H. K.

    2005-07-01

    Full Text Available This paper summarizes the various themes discussed in a roundtable session on the uses and usefulness of genetics for conservation of our European crayfish heritage. After reviewing the importance of characterizing the different genetic stocks (ESU: Evolutionary Significant Units of a species, where morphological criteria used for taxonomy, are utilizable with caution, the present state of knowledge of the phylogeny of European species was determined, in particular for the genus Austropotamobius which occupies most studies. There was a lively debate on the elevation to species rank of A. italicus. The status of knowledge of the taxonomy of Astacus astacus has been presented. Finally, given a major increase in works describing the genetic variability of natural populations of European crayfish, it was evident that an up to date inventory of the different research teams in this field should be developed, for several reasons – (i to describe these teams and their managers (thus facilitating contact (ii to list the species studied and the markers used (iii to give some recommendations on standardizing the use of certain markers or genes so as to allow comparison between the results collected by the various teams, and to apply them on a broader geographic scale.

  5. Are Chinese consumers at risk due to exposure to metals in crayfish? A bioaccessibility-adjusted probabilistic risk assessment.

    Science.gov (United States)

    Peng, Qian; Nunes, Luís M; Greenfield, Ben K; Dang, Fei; Zhong, Huan

    2016-03-01

    Freshwater crayfish, the world's third largest crustacean species, has been reported to accumulate high levels of metals, while the current knowledge of potential risk associated with crayfish consumption lags behind that of finfish. We provide the first estimate of human health risk associated with crayfish (Procambarus clarkii) consumption in China, the world's largest producer and consumer of crayfish. We performed Monte Carlo Simulation on a standard risk model parameterized with local data on metal concentrations, bioaccessibility (φ), crayfish consumption rate, and consumer body mass. Bioaccessibility of metals in crayfish was found to be variable (68-95%) and metal-specific, suggesting a potential influence of metal bioaccessibility on effective metal intake. However, sensitivity analysis suggested risk of metals via crayfish consumption was predominantly explained by consumption rate (explaining >92% of total risk estimate variability), rather than metals concentration, bioaccessibility, or body mass. Mean metal concentrations (As, Cd, Cu, Ni, Pb, Se and Zn) in surveyed crayfish samples from 12 provinces in China conformed to national safety standards. However, risk calculation of φ-modified hazard quotient (HQ) and hazard index (HI) suggested that crayfish metals may pose a health risk for very high rate consumers, with a HI of over 24 for the highest rate consumers. Additionally, the φ-modified increased lifetime risk (ILTR) for carcinogenic effects due to the presence of As was above the acceptable level (10(-5)) for both the median (ILTR=2.5×10(-5)) and 90th percentile (ILTR=1.8×10(-4)), highlighting the relatively high risk of As in crayfish. Our results suggest a need to consider crayfish when assessing human dietary exposure to metals and associated health risks, especially for high crayfish-consuming populations, such as in China, USA and Sweden. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Crayfish as trophic agents: Effect of Austropotamobius torrentium on zoobenthos structure and function in small forest streams

    OpenAIRE

    Weinländer M.; Füreder L.

    2011-01-01

    Crayfish are among the largest and most threatened invertebrates in freshwater habitats. Due to their size, behaviour and feeding activity they may affect structure and function of aquatic ecosystems and their organisms. Despite their importance in many freshwaters and available information on their ecology for several species little is known about the European crayfish Austropotamobius torrentium. In order to evaluate the potential effects of indigenous crayfish presence on the structural an...

  7. Assessing the importance of food for improving noble crayfish culture conditions

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    Rusch J.C.

    2015-01-01

    Full Text Available Captive breeding and crayfish culture are considered important measures in species protection activities. Thus, knowledge on optimal feeding of crayfish in captivity is needed in order to secure minimal mortality and prevent detrimental effects to health. To optimize conditions of crayfish prior to subsequent stocking, feeding trials were conducted with the aim of investigating the connection between food intake, food preference and temperature under near natural conditions. During a five-month period, noble crayfish were fed on fish, carrots, algae and chironomid-larvae according to a pre-defined rotation system, whereby the ambient water temperature ranged from 5 °C to 13 °C, following the natural temperature regime. The results of these feeding trials demonstrate a direct correlation between rising temperature and increasing food intake for water temperatures exceeding 8 °C. Food intake is further influenced by the variety of food items available at any one time. The results also confirm that Astacus astacus has a strong preference for fish and that alternation of food types has an impact on consumption. Our results prompt the following recommendations for optimized feeding conditions of crayfish in captivity prior to their release: (1 a balanced diet containing not only plant tissue but also a significant proportion of animal tissue and (2 the amount of available food must be adjusted according to the carapace length of the crayfish.

  8. EXPERIMENTAL EVIDENCE FOR HOMING IN THE RED SWAMP CRAYFISH, PROCAMBARUS CLARKII

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    BARBARESI S.

    2006-01-01

    Full Text Available The red swamp crayfish, Procambarus clarkii, is an efficient burrower, but its burrow fidelity has been recently questioned. In this study, we aimed at investigating whether individuals of this species are capable to learn the position of a goal (a wet burrow hidden to their sight in experimental tanks and to make more efficient with time their oriented movement towards it. We also analyzed crayfish behavior after having closed one of the two accesses to the goal. Indeed, in successive trials we recorded the crayfish tendency to reduce the distance covered to reach the goal and the time taken, except when they were already familiar to the experimental setting. Memory of the spatial configuration lasted for 16 hours at least and crayfish learned and maintained individual trajectories. The interruption of their usual path always caused a drastic increase of distance and time that however decreased in the successive trials. This study provided also some information of the sensory channels used by P. clarkii to orient. This crayfish, which can be active also during daytime, seemed to adopt a combination of tactile and visual information, together with the possible use of cues (i.e. humidity cues emitted by the goal. Future studies should clarify the paradox of a crayfish species whose individuals, although being physiologically capable to home, seem not to return to the previously occupied burrows at the end of their foraging excursions, notwithstanding the time and energy expended to excavate them.

  9. STUDIES ON THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES ASSOCIATED WITH MUDDY HABITATS

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    HOLDICH D. M.

    2006-01-01

    Full Text Available The white-clawed crayfish, Austropotamobius pallipes, is usually found associated with stony habitats containing obvious refuges in the form of gaps between and under rocks, macrophytes and marginal tree roots, particularly in streams and lakes with clear water and little marginal mud. If the banks are composed of suitable material, then they may also construct and live in burrows. However, the white-clawed crayfish is also found to be abundant in streams, rivers, canals and millraces with deep, anoxic mud and with very little aquatic vegetation. Foraging on the surface of mud may be the only way they can obtain sufficient food in the form of macroinvertebrates and decaying plant matter. Where do crayfish live in this restricted habitat? Dewatering such waterways for essential engineering works, such as desilting, bridge and weir repairs, bank reinforcements, and maintenance of outfalls can provide an excellent opportunity to study the available habitat and the crayfish populations, in addition good estimates of population size and age class distribution can be obtained, although, as with other methods, juveniles tend to be underrepresented. A number of case studies will be given to illustrate the fact that white-clawed crayfish are able to colonize muddy habitats in some numbers. The value of retaining trees with their roots hanging into waterways as a refuge for both crayfish and small fish is highlighted.

  10. Red swamp crayfish: biology, ecology and invasion - an overview

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    Tainã Gonçalves Loureiro

    Full Text Available ABSTRACTAlien species have been transported and traded by humans for many centuries. However, with the era of globalization, biological invasions have reached notable magnitudes. Currently, introduction of alien species is one of the major threats to biodiversity and ecosystem functioning. The North American crayfish Procambarus clarkii is one of the most widely introduced freshwater species in the world, especially due to its high economic importance. It is responsible for great modifications in invaded environments causing irreparable ecological and economic damages. Its impressive ability to successfully colonize a wide range of environments is a consequence of its behavioural and biological characteristics that can adapt to features of the invaded location, conferring to this species a notable ecological plasticity. This review summarizes the available information regarding P. clarkii's biology and invasive dynamics around the world in order to contribute to the understanding of the threats posed by its establishment, as well as to support management and impact mitigation efforts.

  11. Effects of natural flooding and manual trapping on the facilitation of invasive crayfish-native amphibian coexistence in a semi-arid perennial stream

    Science.gov (United States)

    Kats, Lee B.; Bucciarelli, Gary; Vandergon, Thomas L.; Honeycutt, Rodney L.; Mattiasen, Evan; Sanders, Arthur; Riley, Seth P.D.; Kerby, Jacob L.; Fisher, Robert N.

    2013-01-01

    Aquatic amphibians are known to be vulnerable to a myriad of invasive predators. Invasive crayfish are thought to have eliminated native populations of amphibians in some streams in the semi-arid Santa Monica Mountains of southern California. Despite their toxic skin secretions that defend them from native predators, newts are vulnerable to crayfish attacks, and crayfish have been observed attacking adult newts, and eating newt egg masses and larvae. For 15 years, we have observed invasive crayfish and native California newts coexisting in one stream in the Santa Monica Mountains. During that period, we monitored the densities of both crayfish and newt egg mass densities and compared these to annual rainfall totals. After three seasons of below average rainfall, we reduced crayfish numbers by manual trapping. Our long-term data indicated that crayfish did not fare well in years when rainfall is above the historic average. This invasive predator did not evolve with high velocity streams, and observations indicated that southern California storm events washed crayfish downstream, killing many of them. Newts exhibit increased reproduction in years when crayfish numbers were reduced. A comparison with a nearby stream that does not contain crayfish indicated that newt reproduction positively responded to increased rainfall, but that fluctuations were much greater in the stream that contains crayfish. We suggest that rainfall patterns help explain invasive crayfish/newt coexistence and that management for future coexistence may benefit from manual trapping.

  12. KEYNOTE PRESENTATION AND ROUNDTABLE SESSION 4. CRAYFISH PATHOLOGY IN EUROPE:PAST, PRESENT AND A PROGRAMME FOR THE FUTURE

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    EDGERTON B. F.

    2004-01-01

    Full Text Available The devastating affects of disease on European freshwater crayfish are well known as epizootics in wild populations have occurred throughout much of Europe since the mid XVIIIe s. After protracted and rigorous debate, the cause of the disease named crayfish plague was proved to be the fungus Aphanomyces astaci in 1934. In the last 70 years, much of the research conducted in the field of crayfish pathology has concentrated on fungi, especially improving diagnostic techniques for A. astaci. Similarly, diagnostic responses to epizootics in European crayfish have concentrated almost entirely on fungal isolation and/or identification. On the other hand, viruses have proved to be the most important pathogens in the growing global crustacean aquaculture and fishery industries. Rickettsia-like organisms (RLO are also important. Critically, diagnostic techniques necessary to detect the full range of potential pathogens of crayfish are rarely utilized in the field of crayfish pathology in Europe. Histopathological analysis, required for the diagnosis of infections by viruses and RLOs, is absent from most European studies. Epizootics unrelated to A. astaci in European crayfish and epizootics in introduced American crayfish species highlight the inadequate current state of knowledge in the field. Presently, the field is ill-equipped to determine the cause(s of these epizootics. Moreover, crayfish conservation strategies may be undermined and even detrimental to the longterm goals; eg., stocking programs may spread undetected pathogens. Therefore, critical limitations in the field of crayfish pathology have major repercussions in management of freshwater crayfish. Guiding principles and a concept for a trans-European Community research and education program were developed to address this serious issue and are presented herein.

  13. Recent Incidence of Paragonimus westermani Metacercariae in Freshwater Crayfish, Cambaroides similis, from Two Enzootic Sites in Jeollanam-do, Korea

    Science.gov (United States)

    Song, Jin-Ho; Dai, Fuhong; Bai, Xuelian; Kim, Tae-Im; Yang, Hyun-Jong; Kim, Tong-Soo; Cho, Shin-Hyung; Hong, Sung-Jong

    2017-01-01

    An epidemiological study was performed to know the recent infection status of Paragonimus westermani metacercariae (PwMc) in freshwater crayfish, Cambaroides similis, from 2 streams in Jeollanam-do, Republic of Korea. Crayfish were collected from creeks in Bogil-do (Island), Wando-gun, and in a creek near Daeheung Temple in Haenam-gun. The infection rate of crayfish with PwMc in Bogil-do was 89.8%, and the metacercarial burden was 37 PwMc per the infected crayfish. Crayfish in a creek near Daeheung Temple were larger and twice heavier than those in Bogil-do. Of them, 96.5% were infected with PwMc. An average of 140 metacercariae was found in the infected crayfish, almost quadruple to those of Bogil-do. There was a strong correlation between the number of PwMc and body weight of the crayfish. These results suggest that P. westermani metacercariae are still prevalent in crayfish of the 2 regions in Jeollanam-do, Korea. PMID:28719962

  14. REVIEW OF THE NATIONAL RESTOCKING PROGRAMME “ACTIVE PROTECTION OF NATIVE CRAYFISH IN POLAND” 1999-2001

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    ŠMIETANA P.

    2004-01-01

    Full Text Available After the first spread of crayfish plague (aphanomycosis at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of native crayfish in Poland” conducted by the Inland Fisheries Institute, the Department of Ecology, University of Szczecin, the Department of Zoology, Warsaw Agricultural University and the University of Warmia and Mazury that was funded by the EkoFundusz Foundation and Inland Fisheries Institute in 1999-2001. One of the main objectives and results of this programme was the determination of indigenous crayfish distribution in Poland (mainly Astacus astacus and Astacus leptodactylus and the restocking of suitable habitats with indigenous crayfish. The densest populations (> 2 500 adult individuals per hectare were used as a source of restocking material. Restocking was performed in 54 water bodies using a total of 45 200 individuals of A. astacus and 9 800 of A. leptodactylus. Between 2001-2002, the success of the restocking programme was monitored. According to the results obtained so far, the restocking exercise has been successful in at least 60.8% of the cases.

  15. Crayfish as trophic agents: Effect of Austropotamobius torrentium on zoobenthos structure and function in small forest streams

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    Weinländer M.

    2011-07-01

    Full Text Available Crayfish are among the largest and most threatened invertebrates in freshwater habitats. Due to their size, behaviour and feeding activity they may affect structure and function of aquatic ecosystems and their organisms. Despite their importance in many freshwaters and available information on their ecology for several species little is known about the European crayfish Austropotamobius torrentium. In order to evaluate the potential effects of indigenous crayfish presence on the structural and functional composition of the zoobenthic community, we measured population size and densities of three A. torrentium populations and compared macroinvertebrate assemblages and physicochemical parameters in three streams with and three without crayfish. The experimental setup considered crayfish effects at a large scale in defined reaches of pristine headwaters in association with the whole benthic fauna under natural conditions. Presence of A. torrentium significantly affected zoobenthic abundance, diversity and the relative proportions of functional feeding groups. In crayfish streams, especially Trichoptera and collector gatherers were more abundant and diverse, while sites without crayfish had significantly higher abundances and diversities of shredders and wood feeders. Our study provided strong evidence that the presence of the indigenous crayfish A. torrentium had important effects on the trophic cascades of headwater stream communities.

  16. CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

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    REYNOLDS J. D.

    2001-04-01

    Full Text Available The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet occur in these systems, Dreissena has not yet colonized sites with large crayfish populations. In laboratory experiments crayfish of both sexes ranging in size from 32-48 mm carapace length (CL were offered zebra mussels in 7 size classes spanning a range from 3-17 mm total length. Crayfish fed most on small mussels, although there was some correlation between size of crayfish and largest mussels attacked. When eaten mussels were not replaced, crayfish shifted to larger sizes. In the presence of alternative prey, experienced crayfish ate mussels and alternative foods in similar amounts while those who had never encountered zebra mussels nearly always chose the alternative foods first. The possibility of crayfish exerting significant controlling impacts on expanding mussel populations is discussed.

  17. The potential for using red claw crayfish and hybrid African catfish as biological control agents for Schistosoma host snails

    NARCIS (Netherlands)

    Monde, C.; Syampungani, S.; Rico, A.; Brink, van den P.J.

    2017-01-01

    The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After

  18. Cadmium-binding proteins in midgut gland of freshwater crayfish Procambarus clarkii

    Energy Technology Data Exchange (ETDEWEB)

    Del Ramo, J.; Pastor, A.; Torreblanca, A.; Medina, J.; Diza-Mayans, J.

    1989-02-01

    Metallothioneins, metal binding proteins, were originally isolated and characterized by Margoshes and Vallee. These proteins have a high affinity for various heavy metals, particularly cadmium and mercury and have extensively been studied in mammals. Metal binding proteins have been observed in a variety of marine invertebrates; however, there is very little information available on metal binding proteins in freshwater invertebrates, and particularly in freshwater crustaceans. Cadmium is an ubiquitous non essential element which possesses high toxicity to aquatic organisms. Cadmium binding proteins observed in invertebrates have similar characteristics to mammalian metallothioneins. In 1978, the American red crayfish appeared in Albufera Lake and the surrounding rice fields (Valencia, Spain). Albufera Lake and the surrounding rice fields waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and wastewaters in this area. In previous reports the authors studied the toxicity and accumulation of cadmium on Procambarus clarkii of Albufera Lake. This crayfish shows a high resistance to cadmium and a great accumulation rate of this metal in several tissues, including midgut gland. Since Procambarus clarkii shows a high resistance to cadmium, the presence of cadmium binding proteins (Cd-BP) in midgut gland of these crayfish would be expected. This report describes results on the characterization of Cd-BPs obtained from cadmium exposed crayfish Procambarus clarkii, demonstrating their presence in this freshwater crayfish.

  19. Accumulation of Heavy Metals in Crayfish and Fish from Selected Czech Reservoirs

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    Iryna Kuklina

    2014-01-01

    Full Text Available To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše and one contaminated site (Darkovské moře in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr, while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb. The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys.

  20. VITELLOGENIN AND GLUCOSE CONCENTRATIONS IN THE HEMOLYMPH OF WILD AND CONFINED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES LEREBOULLET 1858

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    D’AGARO E.

    2003-04-01

    Full Text Available The white-clawed crayfish (Austropotamobius pallipes is a native species in the Friuli Venezia Giulia region of North-Eastern Italy. This species is under threat because of habitat modifications and water pollution. Conservation policies are needed and the present study is the first step of a restocking programme. Vitellogenin and glucose concentrations in hemolymph of wild animals and after a period of acclimation were examined. Preliminary results showed no significant differences in high-density lipoprotein subunits in females after acclimation. Glucose hemolymph values are also close to normal levels and similar between males and females. Three types of blood cells were identified in the hemolymph: hyaline cells and small and large granule hemocytes. We conclude that glucose and vitellogenin concentrations in the hemolymph of crayfish were not modified under artificial rearing. Metabolic variables are suitable indicators of crayfish ovarian maturation and environmental and physiological stress.

  1. Use of crayfishes as ecological indicator of water quality in natural lakes and city water grid

    Science.gov (United States)

    Sapunov, Valentin; Fedotov, Valery

    2017-04-01

    Crayfishes are organisms having strong demands for water quality. Their different species have different ecological limits. Nobel crayfishes Astacus astacus are organisms with narrow ecological limits need clear water that crayfish Pontastacus leptodactylus. Relation between populations of different crayfishes is criteria of water pollution, level of water bodies eutrofication and ecological pressure. Environmental policy of all countries is directed to water supply by drinking water of high quality and preserving the rivers, lakes and seas, suitable for people and wildlife. However, now freshwater reservoirs and water bodies, as well as including centralized drinking water supply, have been exposed to escalating anthropogenic loading, and risk of sudden emergency pollution. Besides, the problem of providing an ecological safety of the population and prevention of threats of ecological crime and terrorism in a zone of drinking water for many countries. The work is devoted to realization and perspectives of use of the biological early warning stations about changes of quality of surface waters, dangerous to a biota, on the basis of bioelectronic systems as elements of environmental monitoring of water areas. Regular monitoring of crayfish population is a way to follow ecological evolution of ponds. Such a monitoring took place in some lakes of Pskov and Leningrad regions. Ecological characters of crayfishes are appropriate for control of water quality in St. Petersburg and Khabarovsk grids. Fore species were used: Procambarus clarcii, Cherax quadricarinatus, A. astacus and P. leptodactilus. The results of the present work and experiments carried out us to conclude that before assessing any concentration of pollutant on water organisms, it is necessary to investigate not only their development, growth and survival, also their adaptive capacity relative to the variation of environmental parameters. Regular monitoring of heart oscillation was base for control of water

  2. REDUCING THE THREAT TO CONTROL INVASIVE SIGNAL CRAYFISH REDUCING: THE POTENTIAL USE OF PHEROMONES

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    STEBBING P. D.

    2003-04-01

    Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.

  3. Response Function of the Crayfish Caudal Photoreceptor to Hydrodynamic Stimuli

    Science.gov (United States)

    Breite, Sally; Bahar, Sonya; Neiman, Alexander; Moss, Frank

    2002-03-01

    In its abdominal 6th ganglion the crayfish houses 2 light-sensitive neurons (caudal photoreceptors, or CPRs). It is known that these neurons work in tandem with a mechanosensory system of tiny hairs spread across the tailfan, which make synaptic contact with the photoreceptors. A stochastic resonance effect has been shown in this system in which light enhances the transduction of a weak, periodic mechanosensory (hydrodynamic) stimulus. It is not known, however, whether an optimal response from the CPR is induced by a single sine wave cycle or some other waveform. We have experimentally investigated this favorable waveform by driving a tailfan preparation with mechanical 10 Hz correlated Ornstein-Uhlenbeck noise and calculating the response function from the spike-triggered average of the applied noise waveform. We will discuss differences in the shape of the optimal waveform under dark and light conditions, as well as what seems to be a noticeable difference in the magnitude of the animals' response to a noisy stimulus in comparison with a periodic stimulus.

  4. Effect of calcium on excitatory neuromuscular transmission in the crayfish

    Science.gov (United States)

    Bracho, H.; Orkand, R. K.

    1970-01-01

    1. The effects of varying the external Ca concentration from 1·8 to 30 mM/l. (⅛-2 times normal) have been studied at the in vitro crayfish excitatory neuromuscular junction. Electrophysiological techniques were used to record transmembrane junctional potentials from muscle fibres and extracellular junctional currents from the vicinity of nerve terminals. 2. The excitatory junctional potential amplitude was proportional to [Ca]0n, where n varied between 0·68 and 0·94 (mean 0·82) when [Ca]0 was varied from 1·8 to 15 mM/l. 3. The increase in junctional potential amplitude on raising [Ca]0 resulted primarily from an increase in the average number of quanta of excitatory transmitter released from the presynaptic nerve terminal by the nerve impulse. 4. The size of the quanta, synaptic delay, presynaptic potential and electrical properties of the muscle membrane were little affected by changes in calcium concentration in the range studied. PMID:5498460

  5. Evaluation of processed sweet potato-crayfish – soya bean and ...

    African Journals Online (AJOL)

    Feeding studies with 21 day albino rats (Wistar strain) fed ad libitum for twenty eight days with Nutrend (a commercial weaning food used as reference diet) and processed sweet potato-crayfish-soyabean/bambara groundnut mixtures were carried out to assess the suitability of the mixtures as substitutes for Nutrend.

  6. Interactions between accumulated copper, bacterial community structure and histamine levels in crayfish meat during storage.

    NARCIS (Netherlands)

    Soedarini, B.; van Gestel, C.A.M.; van Straalen, N.M.; Widianarko, B.; Roling, W.F.M.

    2014-01-01

    BACKGROUND: Pollution in aquaculture areas may negatively impact edible species and threaten seafood quality and safety. The aim of this study was to determine the interaction between copper and bacteria in the aquatic habitat and their impact upon crustaceans. Marbled crayfish was chosen as a model

  7. Use of smartphones (iPhone, Android, etc. for the field identification of European crayfish

    Directory of Open Access Journals (Sweden)

    De Vaugelas J.

    2011-11-01

    Full Text Available Species identification keys are the most precise and unambiguous tools to properly identify a specimen down to the species or infra-species level. This is especially true when the key is richly illustrated with precise pictures or videos. Recent smartphones (iPhone, Android, etc. can access through the 3G network to an unlimited and rapidly growing set of multimedia data on each species (photos, videos, audios. They become convenient tools to use in the field instead of traditional paper field-guides with a limited number of illustrations. A student project at the University of Nice, France, proposed to adapt to smartphones the Holdich and Vigneux “key to crayfish in Europe”. A prototype, in English, has been prepared and presented to the European Crayfish Congress in Poitiers, France, 26–29 October, 2010. It needs now to be discussed with taxonomy and field specialists in order to (1 increase the number of photos and videos and (2 complete and improve its audio part. Then, a multilingual version could be designed, so that field specialists of all European countries may use it. As the database underlying the project is wiki-compatible, a multilingual version could be designed as a collaborative effort within the crayfish community. Data on each species (biology, ecology, distribution, etc. could be added in a second phase, as a geolocalisation module is linked to the database. Then the identification of invasive species could be quickly related to maps, in order to alert the crayfish community.

  8. Fishes, mussels, crayfishes, and aquatic habitats of the Hoosier-Shawnee ecological assessment area

    Science.gov (United States)

    M. Burr Brooks; Justin T. Sipiorski; Matthew R. Thomas; Kevin S. Cummings; Christopher A. Taylor

    2004-01-01

    The Hoosier-Shawnee Ecological Assessment Area, part of the Coastal Plain and Interior Low Plateau physiographic provinces, includes 194 native fish species, 76 native mussel species, and 34 native crayfish species. Five of the subregions (e.g., Mississippi Embayment) that make up the assessment area were recently ranked as either globally or bioregionally outstanding...

  9. Interactions between crayfish, benthic invertebrates, macrophyte roots and sediment in a littoral zone

    Czech Academy of Sciences Publication Activity Database

    Ságová-Marečková, Markéta

    2002-01-01

    Roč. 155, č. 4 (2002), s. 645-665 ISSN 0003-9136 Grant - others:GA the Center for Limnology of the UW-Madison(XX) BSR8514330 Institutional research plan: CEZ:AV0Z5020903 Keywords : predation * food * crayfish Subject RIV: EE - Microbiology, Virology Impact factor: 1.195, year: 2002

  10. Effects of chronic cocaine, morphine and methamphetamine on the mobility, immobility and stereotyped behaviors in crayfish.

    Science.gov (United States)

    Imeh-Nathaniel, Adebobola; Rincon, Natalia; Orfanakos, Vasiliki Bessie; Brechtel, Leanne; Wormack, Leah; Richardson, Erika; Huber, Robert; Nathaniel, Thomas I

    2017-08-14

    The worth of crayfish as a model system for studies of addiction was not previously recognized because a drug-reward phenomenon had not been documented in this model system. In our previous experiments, we demonstrate that the crayfish natural reward pathways are sensitive to human drugs of abuse. This finding supports crayfish as a suitable model to characterize specific behaviors that are relevant in drug addiction research, and the current study builds on our previous findings. The aim of the present study was to investigate unconditioned neurobehavioral effects of repeated treatment regimens using cocaine, morphine, and methamphetamine for three consecutive days. We analyzed mobility, immobility and characterized stereotypic behaviors following intracardial infusions of 2.0μg/g or 10.0μg/g doses of cocaine, morphine, and methamphetamine for three days. The results showed that systemic cocaine, morphine, and methamphetamine increased mobility at a low dose of 2.0μg/g more effectively than a high dose of 10.0μg/g, while simultaneously showing that the high dose exerted a more prominent effect in increasing immobility. Moreover, systemic cocaine, morphine, and methamphetamine injections have discerning effects towards a group of defined unconditioned stereotyped behavioral patterns associated with each drug, rather than a shared universal behavioral effect. These findings provide insight into the behavioral and pharmacological basis responsible for the unconditioned effects of these drugs in crayfish. Copyright © 2017. Published by Elsevier B.V.

  11. A global review of freshwater crayfish temperature tolerance, preference, and optimal growth

    Science.gov (United States)

    Westhoff, Jacob T.; Rosenberger, Amanda E.

    2016-01-01

    Conservation efforts, environmental planning, and management must account for ongoing ecosystem alteration due to a changing climate, introduced species, and shifting land use. This type of management can be facilitated by an understanding of the thermal ecology of aquatic organisms. However, information on thermal ecology for entire taxonomic groups is rarely compiled or summarized, and reviews of the science can facilitate its advancement. Crayfish are one of the most globally threatened taxa, and ongoing declines and extirpation could have serious consequences on aquatic ecosystem function due to their significant biomass and ecosystem roles. Our goal was to review the literature on thermal ecology for freshwater crayfish worldwide, with emphasis on studies that estimated temperature tolerance, temperature preference, or optimal growth. We also explored relationships between temperature metrics and species distributions. We located 56 studies containing information for at least one of those three metrics, which covered approximately 6 % of extant crayfish species worldwide. Information on one or more metrics existed for all 3 genera of Astacidae, 4 of the 12 genera of Cambaridae, and 3 of the 15 genera of Parastacidae. Investigations employed numerous methodological approaches for estimating these parameters, which restricts comparisons among and within species. The only statistically significant relationship we observed between a temperature metric and species range was a negative linear relationship between absolute latitude and optimal growth temperature. We recommend expansion of studies examining the thermal ecology of freshwater crayfish and identify and discuss methodological approaches that can improve standardization and comparability among studies.

  12. Cadmium accumulation in the crayfish, Procambarus clarkii, using graphite furnace atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Mayans, J.; Hernandez, F.; Medina, J.; Del Ramo, J.; Torreblanca, A.

    1986-11-01

    Lake Albufera and the surrounding rice-field waters are being subject to very heavy loads of sewage and toxic industrial residues (including heavy metals and pesticides) from the many urban and wastewaters in this area. The American red crayfish Procambarus clarkii is native to the Louisiana marshes (USA). In 1978, the crayfish appeared in Lake Albufera near Valencia (Spain), and presently, without adequate sanitary controls, the crayfish is being fished commercially for human consumption. In view of this interest, it is important to have accurate information on concentrations of cadmium in natural waters and cadmium levels of tissues of freshwaters animals used as human food, as well as the accumulation rates of this metal in this animal. In the present study, the authors investigated the accumulation of cadmium in several tissues of the red crayfish, P clarkii (Girard) from Lake Albufera following cadmium exposure. Determinations of cadmium were made by flameless atomic absorption spectroscopy and the standard additions method. Digestion of samples was made by wet ashing in open flasks with concentrated HNO/sub 3/ at 80-90/sup 0/C.

  13. Determination of lead in treated crayfish Procambarus clarkii: accumulation in different tissues

    Energy Technology Data Exchange (ETDEWEB)

    Pastor, A.; Medina, J.; Del Ramo, J.; Torreblanca, A.; Diaz-Mayans, J.; Hernandez, F.

    1988-09-01

    The continual loading of trace metals into our environment represents a water pollution problem due to their toxic effects on aquatic biota. In addition, metal ions can be incorporated into food chains and concentrated by aquatic organisms to a level that affects their physiological state. There are several investigations on the toxic effects and bioaccumulation of lead in fishes, molluscs, and crustaceans. Lake Albufera (Valencia, Spain) and the surrounding rice-field waters are subjected to large loads of sewage and toxic industrial residues (including heavy metals) from many urban wastewaters in the area. In 1978, the American red crayfish Procambarus clarkii (Girard) appeared in Lake Albufera. The crayfish have reached a high density producing ecological and agricultural economic problems in rice crops. The crayfish is being fished commercially for human consumption without adequate protection to human health. The purpose of the present study was to investigate the accumulation of lead in tissues of the crayfish P. clarkii following short term lead exposure at several sublethal concentrations. The gills, midgut glands, antennal glands and muscle were analyzed by atomic absorption spectrophotometry.

  14. Genetic characterization of Western European noble crayfish populations (Astacus astacus) for advanced conservation management strategies

    NARCIS (Netherlands)

    Schrimpf, A.; Piscione, M.; Cammaerts, R.; Collas, M.; Herman, D.; Jung, A.; Ottburg, F.; Roessink, I.; Rollin, X.; Schulz, R.; Theissinger, K.

    2017-01-01

    One central goal of conservation biology is to conserve the genetic diversity of species in order to protect their adaptive potential. The main objective of this study was to identify management units (MUs) for the threatened noble crayfish (Astacus astacus) in Western Europe by utilizing

  15. Photodynamic damage of glial cells in crayfish ventral nerve cord

    Science.gov (United States)

    Kolosov, M. S.; Duz, E.; Uzdensky, A. B.

    2011-03-01

    Photodynamic therapy (PDT) is a promising method for treatment of brain tumors, the most of which are of glial origin. In the present work we studied PDT-mediated injury of glial cells in nerve tissue, specifically, in abdominal connectives in the crayfish ventral nerve cord. The preparation was photosensitized with alumophthalocyanine Photosens and irradiated 30 min with the diode laser (670 nm, 0.1 or 0.15 W/cm2). After following incubation in the darkness during 1- 10 hours it was fluorochromed with Hoechst 33342 and propidium iodide to reveal nuclei of living, necrotic and apoptotic cells. The chain-like location of the glial nuclei allowed visualization of those enveloping giant axons and blood vessels. The level of glial necrosis in control preparations was about 2-5 %. Apoptosis was not observed in control preparations. PDT significantly increased necrosis of glial cells to 52 or 67 % just after irradiation with 0.1 or 0.15 W/cm2, respectively. Apoptosis of glial cells was observed only at 10 hours after light exposure. Upper layers of the glial envelope of the connectives were injured stronger comparing to deep ones: the level of glial necrosis decreased from 100 to 30 % upon moving from the connective surface to the plane of the giant axon inside the connective. Survival of glial cells was also high in the vicinity of blood vessels. One can suggest that giant axons and blood vessels protect neighboring glial cells from photodynamic damage. The mechanism of such protective action remains to be elucidated.

  16. Electrophysiological Evidence for Intrinsic Pacemaker Currents in Crayfish Parasol Cells.

    Directory of Open Access Journals (Sweden)

    DeForest Mellon

    Full Text Available I used sharp intracellular electrodes to record from parasol cells in the semi-isolated crayfish brain to investigate pacemaker currents. Evidence for the presence of the hyperpolarization-activated inward rectifier potassium current was obtained in about half of the parasol cells examined, where strong, prolonged hyperpolarizing currents generated a slowly-rising voltage sag, and a post-hyperpolarization rebound. The amplitudes of both the sag voltage and the depolarizing rebound were dependent upon the strength of the hyperpolarizing current. The voltage sag showed a definite threshold and was non-inactivating. The voltage sag and rebound depolarization evoked by hyperpolarization were blocked by the presence of 5-10 mM Cs2+ ions, 10 mM tetraethyl ammonium chloride, and 10 mM cobalt chloride in the bathing medium, but not by the drug ZD 7288. Cs+ ions in normal saline in some cells caused a slight increase in mean resting potential and a reduction in spontaneous burst frequency. Many of the neurons expressing the hyperpolarization-activated inward potassium current also provided evidence for the presence of the transient potassium current IA, which was inferred from experimental observations of an increased latency of post-hyperpolarization response to a depolarizing step, compared to the response latency to the depolarization alone. The latency increase was reduced in the presence of 4-aminopyridine (4-AP, a specific blocker of IA. The presence of 4-AP in normal saline also induced spontaneous bursting in parasol cells. It is conjectured that, under normal physiological conditions, these two potassium currents help to regulate burst generation in parasol cells, respectively, by helping to maintain the resting membrane potential near a threshold level for burst generation, and by regulating the rate of rise of membrane depolarizing events leading to burst generation. The presence of post-burst hyperpolarization may depend upon IA channels in

  17. GENETIC COMPARISONS OF GERMAN POPULATIONS OF THE STONE CRAYFISH, AUSTROPOTAMOBIUS TORRENTIUM (CRUSTACEA: ASTACIDAE

    Directory of Open Access Journals (Sweden)

    SCHUBART C. D.

    2006-01-01

    Full Text Available Austropotamobius torrentium (SCHRANK, 1803 is the smallest of the European native crayfish species and has probably never been of economic interest. It is confined to headwaters and adapted to cold water with high flow through and rocky environments. These properties make the stone crayfish a useful species for population genetics and phylogeographic studies. Representatives were collected from 18 localities throughout southern Germany and analysed with two mitochondrial genetic markers. Initial results revealed that German populations of A. torrentium from the Danube and Rhine tributaries share identical haplotypes in 528 basepairs of 16S rRNA and 658 basepairs of the COI gene. Rare haplotypes of the COI genes were occasionally encountered and apparently restricted to southwestern Bavaria. Only three variable sites were found over a length of 658 basepairs in 45 German, Swiss and Austrian stone crayfish resulting in five different haplotypes, with the prevalence of one most common haplotype. Here we show that in German populations rare haplotypes are not randomly distributed, but found in higher frequencies in the Bavarian Alps of the Allgäu and in adjacent Tyrol. On the other hand, stone crayfish population from the Bavarian Forest and the Rhine tributaries appear genetically impoverished, so far only showing the most common haplotype. Consequently, there are significant differences between the Allgäu populations and the rest of the German populations in haplotype frequencies, resulting in a relatively high FST value. This finding is of importance for future conservation efforts of stone crayfish populations in Germany and Austria.

  18. Accumulation and toxicity of aluminium-contaminated food in the freshwater crayfish, Pacifastacus leniusculus.

    Science.gov (United States)

    Woodburn, Katie; Walton, Rachel; McCrohan, Catherine; White, Keith

    2011-10-01

    The accumulation and toxicity of aluminium in freshwater organisms have primarily been examined following aqueous exposure. This study investigated the uptake, excretion and toxicity of aluminium when presented as aluminium-contaminated food. Adult Pacifastacus leniusculus were fed control (3 μg aluminium/g) or aluminium-spiked pellets (420 μg aluminium/g) over 28 days. Half the crayfish in each group were then killed and the remainder fed control pellets for a further 10 days (clearance period). Concentrations of aluminium plus the essential metals calcium, copper, potassium and sodium were measured in the gill, hepatopancreas, flexor muscle, antennal gland (kidney) and haemolymph. Histopathological analysis of tissue damage and sub-cellular distribution of aluminium were examined in the hepatopancreas. Haemocyte number and protein concentration in the haemolymph were analysed as indicators of toxicity. The hepatopancreas of aluminium-fed crayfish contained significantly more aluminium than controls on days 28 and 38, and this amount was positively correlated with the amount ingested. More than 50% of the aluminium in the hepatopancreas of aluminium-fed crayfish was located in sub-cellular fractions thought to be involved in metal detoxification. Aluminium concentrations were also high in the antennal glands of aluminium-fed crayfish suggesting that some of the aluminium lost from the hepatopancreas is excreted. Aluminium exposure via contaminated food caused inflammation in the hepatopancreas but did not affect the number of circulating haemocytes, haemolymph ion concentrations or protein levels. In conclusion, crayfish accumulate, store and excrete aluminium from contaminated food with only localised toxicity. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. THE DISPERSION OF THE APHANOMYCES ASTACI-CARRIER PACIFASTACUS LENIUSCULUS BY HUMANS REPRESENTS THE MAIN CAUSE OF DISAPPEARANCE OF THE INDIGENOUS CRAYFISH AUSTROPOTAMOBIUS PALLIPES IN NAVARRA

    Directory of Open Access Journals (Sweden)

    DIÉGUEZ-URIBEONDO J.

    2006-01-01

    Full Text Available The tendency of population decline of the indigenous crayfish, Austropotamobius pallipes, in Navarra was reduced by the implementation of a plan of restoration in 1996. Recently, a new drop in population numbers has been noticed. In 2004, an extensive survey was carried out to study the reasons for this decline. The results showed that indigenous crayfish had disappeared from 37 out of 73 areas where they were previously present. The main causes were found to be: presence of signal crayfish, Pacifastacus leniusculus (40%, habitat alterations (13% and climatic drought (11%. In 35% of the cases, the reasons could no be determined. Disappearances that were associated with presence of signal crayfish were assigned to crayfish plague. These disappearances have occurred a few years after an increase in the number signal crayfish fishery areas. The new populations of P. leniusculus followed a patchy distribution, and were clearly associated with human introductions. This work shows that signal crayfish currently represents the main reason for decline of indigenous crayfish and that humans play a major role in the dispersal of these carriers of the causative organism of crayfish plague, A. astaci.

  20. First record of the invasive Australian redclaw crayfish Cherax quadricarinatus (von Martens, 1868 in the Crocodile River, Kruger National Park, South Africa

    Directory of Open Access Journals (Sweden)

    Robin M. Petersen

    2017-03-01

    Full Text Available The redclaw crayfish Cherax quadricarinatus (von Martens, 1868, a robust freshwater crayfish native to Australia and Papua New Guinea, has now been recorded from the Kruger National Park (KNP. Previously absent from the Crocodile River, SAN Parks received a report in February 2016 of redclaw crayfish below the Van Graan Dam on the border of the KNP. Here, we provide evidence of the presence of redclaw crayfish in the Crocodile River. A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the KNP and the Komati Catchment. The negative impacts of global crayfish introductions justify efforts to discourage further introductions and prevent their secondary spread. Conservation implications: A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the Kruger National Park and the Komati Catchment.

  1. A SURVEY OF THE WHITE-CLAWED CRAYFISH,AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET, AND OF WATERQUALITY IN TWO CATCHMENTS OF EASTERN IRELAND.

    Directory of Open Access Journals (Sweden)

    DEMERS A.

    2002-07-01

    Full Text Available The white-clawed crayfish, Austropotamobius pallipes (Lereboullet, is the only crayfish species found in Ireland. Because of the prohibition on importation of exotic species of crayfish onto the island and of its relatively clean rivers up to now, Ireland has kept an abundant population of crayfish. A survey was conducted in the catchments of the Liffey and Boyne rivers, in eastern Ireland to assess water quality and to sample crayfish populations. The aim of the study was to evaluate the water quality requirements of the white-clawed crayfish in Ireland. Baited traps and nets were used to sample crayfish while water quality was measured with biological indices calculated from samples of macroinvertebrates. Distribution of this crayfish species is patchy in the Liffey catchment and seems to be related to factors such as soil types and water quality. They were not found in the downstream part of the river Liffey possibly due to poor water quality. In the Boyne catchment, no crayfish were found in most of the catchment. They were only present in the Kells Blackwater subcatchment. This may be due to an earlier outbreak of the fungal plague caused by Aphanomyces astaci. The disease was discovered in lakes at the top of some of the tributaries of the Boyne in 1987 and it probably spread from there through the whole catchment.

  2. Behavior and season affect crayfish detection and density inference using environmental DNA.

    Science.gov (United States)

    Dunn, Nicholas; Priestley, Victoria; Herraiz, Alba; Arnold, Richard; Savolainen, Vincent

    2017-10-01

    Although the presence/absence of aquatic invertebrates using environmental DNA (eDNA) has been established for several species, inferring population densities has remained problematic. The invasive American signal crayfish, Pacifastacus leniusculus (Dana), is the leading cause of decline in the UK's only native crayfish species, Austropotamobius pallipes (Lereboullet). Methods to detect species at low abundances offer the opportunity for the early detection, and potential eradication, of P. leniusculus before population densities reach threatening levels in areas occupied by A. pallipes . Using a factorial experimental design with aquaria, we investigated the impacts of biomass, sex ratio, and fighting behavior on the amount of eDNA released by P. leniusculus , with the aim to infer density per aquarium depending on treatments. The amount of target eDNA in water samples from each aquarium was measured using the quantitative Polymerase Chain Reaction. We show that the presence of eggs significantly increases the concentration of crayfish eDNA per unit of mass, and that there is a significant relationship between eDNA concentration and biomass when females are egg-bearing. However, the relationship between crayfish biomass and eDNA concentration is lost in aquaria without ovigerous females. Female-specific tanks had significantly higher eDNA concentrations than male-specific tanks, and the prevention of fighting did not impact the amount of eDNA in the water. These results indicate that detection and estimate of crayfish abundance using eDNA may be more effective while females are ovigerous. This information should guide further research for an accurate estimation of crayfish biomass in the field depending on the season. Our results indicate that detection and quantification of egg-laying aquatic invertebrate species using eDNA could be most successful during periods when eggs are developing in the water. We recommend that practitioners consider the reproductive

  3. Crustacean hyperglycemic hormone is synthesized in the eyestalk and brain of the crayfish Procambarus clarkii.

    Directory of Open Access Journals (Sweden)

    Rosaura Loredo-Ranjel

    Full Text Available Crustacean hyperglycemic hormone (CHH is a neuropeptide that is synthesized, stored, and released by brain and eyestalk structures in decapods. CHH participates in the regulation of several mechanisms, including increasing the level of glucose in hemolymph. Although CHH mRNA levels have been quantified and the CHH protein has been localized in various structures of the crayfish P. clarkii, CHH synthesis has only been reported in the X-organ-sinus gland (XO-SG. Therefore, the aim of this study was to use in situ hybridization to determine whether CHH mRNA is located in other structures, including the putative pacemaker, eyestalk and brain, of crayfish P. clarkii at two times of day. CHH mRNA was observed in both the eyestalk and the brain of P. clarkii, indicating that CHH is synthesized in several structures in common with other crustaceans, possibly to provide metabolic support for these regions by increasing glucose levels.

  4. Crustacean hyperglycemic hormone is synthesized in the eyestalk and brain of the crayfish Procambarus clarkii.

    Science.gov (United States)

    Loredo-Ranjel, Rosaura; Fanjul-Moles, María Luisa; Escamilla-Chimal, Elsa G

    2017-01-01

    Crustacean hyperglycemic hormone (CHH) is a neuropeptide that is synthesized, stored, and released by brain and eyestalk structures in decapods. CHH participates in the regulation of several mechanisms, including increasing the level of glucose in hemolymph. Although CHH mRNA levels have been quantified and the CHH protein has been localized in various structures of the crayfish P. clarkii, CHH synthesis has only been reported in the X-organ-sinus gland (XO-SG). Therefore, the aim of this study was to use in situ hybridization to determine whether CHH mRNA is located in other structures, including the putative pacemaker, eyestalk and brain, of crayfish P. clarkii at two times of day. CHH mRNA was observed in both the eyestalk and the brain of P. clarkii, indicating that CHH is synthesized in several structures in common with other crustaceans, possibly to provide metabolic support for these regions by increasing glucose levels.

  5. Crayfish process leaf litter in tropical streams even when shredding insects are common

    OpenAIRE

    Coughlan, Jacqui; Pearson, R.G.; Boyero, Luz

    2010-01-01

    Comparisons of leaf-litter processing in streams suggest that tropical streams have fewer leaf shredders than temperate streams and that insect shredders might be replaced by other taxa such as Crustacea in tropical systems. Australian wet-tropical streams have abundant insect shredders, and also abundant crayfish, which may contribute to litter processing. We monitored litter input and retention in a Queensland rainforest stream to determine availability of litter in different seasons, and w...

  6. Multiple drivers of decline in the global status of freshwater crayfish (Decapoda: Astacidea).

    Science.gov (United States)

    Richman, Nadia I; Böhm, Monika; Adams, Susan B; Alvarez, Fernando; Bergey, Elizabeth A; Bunn, John J S; Burnham, Quinton; Cordeiro, Jay; Coughran, Jason; Crandall, Keith A; Dawkins, Kathryn L; DiStefano, Robert J; Doran, Niall E; Edsman, Lennart; Eversole, Arnold G; Füreder, Leopold; Furse, James M; Gherardi, Francesca; Hamr, Premek; Holdich, David M; Horwitz, Pierre; Johnston, Kerrylyn; Jones, Clive M; Jones, Julia P G; Jones, Robert L; Jones, Thomas G; Kawai, Tadashi; Lawler, Susan; López-Mejía, Marilu; Miller, Rebecca M; Pedraza-Lara, Carlos; Reynolds, Julian D; Richardson, Alastair M M; Schultz, Mark B; Schuster, Guenter A; Sibley, Peter J; Souty-Grosset, Catherine; Taylor, Christopher A; Thoma, Roger F; Walls, Jerry; Walsh, Todd S; Collen, Ben

    2015-02-19

    Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world's 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach.

  7. Histological analysis of thelohaniasis in white-clawed crayfish Austropotamobius pallipes complex

    Directory of Open Access Journals (Sweden)

    Quaglio F.

    2011-09-01

    Full Text Available From 2004 to 2006, a parasitological survey aimed at the detection of the microsporidian parasite Thelohania contejeani Henneguy was carried out on 177 wild white-clawed crayfish (Austropotamobius pallipes complex captured in six streams and rivers of the province of Belluno in north-eastern Italy. Microscopical examination of the skeletal muscles, and histological analysis applying different histochemical stains to full transverse and sagittal sections of the cephalothorax and abdomen were carried out. Transmission electron microscopy (TEM was also conducted on the parasites recovered during the survey. Out of 177 crayfish examined, Thelohania contejeani (Microsporidia, Thelohaniidae was present in only one crayfish from the Vena d’oro creek. The parasite was detected in the skeletal muscles in several developmental stages, including mature spores, which represented the most common stage recovered. Sporophorous vesicles were also present. Histological examination revealed that the fibres of the skeletal, cardiac and intestinal muscles were filled with spores. Melanin infiltrations were focally present in the infected striated muscles. The gill phagocytic nephrocytes were engulfed by small masses of spores. Among the staining techniques applied, Crossman’s trichrome stain represented the most effective method of detecting T. contejeani.

  8. UTILIZATION OF WATER CRESS (NASTURTIUM OFFICINALE L. IN NOBLE CRAYFISH (ASTACUS ASTACUS FEEDING

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    D’AGARO E.

    2006-01-01

    Full Text Available Juvenile Astacus astacus (initial b.w.: 0.98 ± 0.06 g were cultured (30 crayfish/m2 in 200l tanks for 69 days. The experimental design was composed of three treatments as follows: control diet (C (crude protein: 28.4% of the total dried matter, “DM”; ether extract: 6.22% DM, water cress (W (crude protein: 20.7% DM; ether extract: 1.9% DM and control diet + water cress (C + W with thee replicates per treatment. Relative growth rate improved significantly (P < 0.05 in crayfish fed C + W (+ 110% compared to W (+ 43% and the control diet (+ 36%. Gross protein and lipid retentions of the treatment C + W were significantly higher than the control diet and water cress fed alone. At the end of the experiment, a higher survival rate of A. astacus was observed (P < 0.05 in the treatment C + W (67% and C (71% compared to the W (58%. These results suggest that the plant water cress (Nasturtium officinale can be used as supplemental food in noble crayfish feeding.

  9. Recent Incidence ofParagonimus westermaniMetacercariae in Freshwater Crayfish,Cambaroides similis, from Two Enzootic Sites in Jeollanam-do, Korea.

    Science.gov (United States)

    Song, Jin-Ho; Dai, Fuhong; Bai, Xuelian; Kim, Tae-Im; Yang, Hyun-Jong; Kim, Tong-Soo; Cho, Shin-Hyung; Hong, Sung-Jong

    2017-06-01

    An epidemiological study was performed to know the recent infection status of Paragonimus westermani metacercariae (PwMc) in freshwater crayfish, Cambaroides similis , from 2 streams in Jeollanam-do, Republic of Korea. Crayfish were collected from creeks in Bogil-do (Island), Wando-gun, and in a creek near Daeheung Temple in Haenam-gun. The infection rate of crayfish with PwMc in Bogil-do was 89.8%, and the metacercarial burden was 37 PwMc per the infected crayfish. Crayfish in a creek near Daeheung Temple were larger and twice heavier than those in Bogil-do. Of them, 96.5% were infected with PwMc. An average of 140 metacercariae was found in the infected crayfish, almost quadruple to those of Bogil-do. There was a strong correlation between the number of PwMc and body weight of the crayfish. These results suggest that P. westermani metacercariae are still prevalent in crayfish of the 2 regions in Jeollanam-do, Korea.

  10. Microevolution of the noble crayfish (Astacus astacus) in the Southern Balkan Peninsula.

    Science.gov (United States)

    Laggis, Anastasia; Baxevanis, Athanasios D; Charalampidou, Alexandra; Maniatsi, Stefania; Triantafyllidis, Alexander; Abatzopoulos, Theodore J

    2017-05-30

    The noble crayfish (Astacus astacus) displays a complex historical and contemporary genetic status in Europe. The species divergence has been shaped by geological events (i.e. Pleistocene glaciations) and humanly induced impacts (i.e. translocations, pollution, etc.) on its populations due to species commercial value and its niche degradation. Until now, limited genetic information has been procured for the Balkan area and especially for the southernmost distribution of this species (i.e. Greece). It is well known that the rich habitat diversity of the Balkan Peninsula offers suitable conditions for genetically diversified populations. Thus, the present manuscript revisits the phylogenetic relationships of the noble crayfish in Europe and identifies the genetic make-up and the biogeographical patterns of the species in its southern range limit. Mitochondrial markers (i.e. COI and 16S) were used in order to elucidate the genetic structure and diversity of the noble crayfish in Europe. Two of the six European haplotypic lineages, were found exclusively in Greece. These two lineages exhibited greater haplotypic richness when compared with the rest four (of "Central European" origin) while they showed high genetic diversity. Divergence time analysis identified that the majority of this divergence was captured through Pleistocene, suggesting a southern glacial refugium (Greece, southern Balkans). Furthermore, six microsatellite markers were used in order to define the factors affecting the genetic structure and demographic history of the species in Greece. The population structure analysis revealed six to nine genetic clusters and eight putative genetic barriers. Evidence of bottleneck effects in the last ~5000 years (due to climatic and geological events and human activities) is also afforded. Findings from several other research fields (e.g. life sciences, geology or even archaeology) have been utilized to perceive the genetic make-up of the noble crayfish. The

  11. It takes time to see the menu from the body: an experiment on stable isotope composition in freshwater crayfishes

    Directory of Open Access Journals (Sweden)

    Jussila J.

    2015-01-01

    Full Text Available For many applications and ecological studies in which wild individuals are brought to laboratory it would be essential to know accurately how fast novel diet is reflected in composition of different tissues. To study the effects of two different diets on the stable isotope composition of freshwater crayfish muscle and hemolymph, we conducted a three month experiment on noble crayfish (Astacus astacus and signal crayfish (Pacifastacus leniusculus by feeding them sweet corn (Zea mays or Baltic herring (Clupea harengus membras as novel food. During the experiment, the crayfish were given 0.4 g of selected food daily and the amount consumed was recorded. The samples for the stable isotope analyses were taken at the commencement of the experiment (initial control and three times (hemolymph or twice (muscle tissue during the experiment. We found that stable isotope changes can be similarly, and rather slowly, detected from muscle tissue and hemolymph under studied conditions. Hemolymph sampling, being non-lethal, can be recommended as a practical sampling method. Our results confirm earlier reports according to which diet changes reflect to crayfish isotope ratios slowly implying that isotope ratios indicate long-term diet.

  12. Effects of synbiotics on immunity and disease resistance of narrow-clawed crayfish, Astacus leptodactylus leptodactylus (Eschscholtz, 1823).

    Science.gov (United States)

    Safari, Omid; Paolucci, Marina; Motlagh, Hamidreza Ahmadnia

    2017-05-01

    The aim of this study was to evaluate the effects of prebiotics (mannanoligosaccharide and xylooligosaccharide), probiotics (Enterococcus faecalis and Pediococcus acidilactici) and synbiotics for 126 days on the immune responses, hemolymph indices, antioxidant enzymes, and biological responses after a 48-hour Aeromonas hydrophila exposure of sub-adult crayfish (11.45 ± 1.87 g). Most antibacterial activities were observed in the shell mucus of crayfish fed a diet containing xylooligosaccharide + E. faecalis and mannanoligosaccharide + Pediococcus acidilactici against Nocardia brasilience and Vibrio harveyi (p < 0.05). Feeding crayfish a xylooligosaccharide + E. faecalis diet increased protein levels and the activities of alkaline phosphatase and lysozyme in the shell mucus after the feeding trial and 48 h after the A. hydrophila-injection challenge (p < 0.05). The highest ratio of the lactobacillus count to the total viable count was observed in synbiotic diets (p < 0.05). Feeding crayfish a xylooligosaccharide + E. faecalis diet increased the growth rate and the resistance to the A. hydrophila-injection challenge (p < 0.05). These results revealed that feeding crayfish with synbiotic diets was more effective than a single administration with prebiotics and probiotics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Predatory functional response and prey choice identify predation differences between native/invasive and parasitised/unparasitised crayfish.

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    Neal R Haddaway

    Full Text Available BACKGROUND: Invasive predators may change the structure of invaded communities through predation and competition with native species. In Europe, the invasive signal crayfish Pacifastacus leniusculus is excluding the native white clawed crayfish Austropotamobius pallipes. METHODOLOGY AND PRINCIPAL FINDINGS: This study compared the predatory functional responses and prey choice of native and invasive crayfish and measured impacts of parasitism on the predatory strength of the native species. Invasive crayfish showed a higher (>10% prey (Gammarus pulex intake rate than (size matched natives, reflecting a shorter (16% prey handling time. The native crayfish also showed greater selection for crustacean prey over molluscs and bloodworm, whereas the invasive species was a more generalist predator. A. pallipes parasitised by the microsporidian parasite Thelohania contejeani showed a 30% reduction in prey intake. We suggest that this results from parasite-induced muscle damage, and this is supported by a reduced (38% attack rate and increased (30% prey handling time. CONCLUSIONS AND SIGNIFICANCE: Our results indicate that the per capita (i.e., functional response difference between the species may contribute to success of the invader and extinction of the native species, as well as decreased biodiversity and biomass in invaded rivers. In addition, the reduced predatory strength of parasitized natives may impair their competitive abilities, facilitating exclusion by the invader.

  14. Comparative study of freshwater crayfish, Cherax spp. (crustaceae: decapoda: parastacidae) from Papua, Indonesia based on length-weight analysis

    Science.gov (United States)

    Hamidah, H.; Abinawanto, Bowolaksono, A.

    2017-07-01

    The freshwater crayfish is one of the most important fish species as the protein resources. Lake and rivers are the habitat of crayfish in Papua. Morphological characters of crayfish, such as color, total body lengths (L) and body weight (W) were influenced by the habitat. The purpose of the study, therefore, was to compare the total body length and body weight as well as the unique color of crayfish from Uter lake (Atinjo district), Seremuk river (Haha village), Baliem river (Pike village; Hubukiak district, Jayawijaya), and Baliem river (Wesaput village; Wesaput district). Length-weight (body length; LB versus wet weight; WWT) relationships were determined for male and female crayfish (Cherax spp.) The length-weight relationships of total individuals was W = 0,022215.L3,159. This regression differed significantly (R2 = 97.5 %) between locations. Both males and females exhibited positive allometric growth as statistical difference was observed in the mean of the wet weight and body length between males and females. Besides, Canonical function was subjected to determine population distribution based on length-weight data.

  15. 'Leaves and eats shoots': direct terrestrial feeding can supplement invasive red swamp crayfish in times of need.

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    Jonathan Grey

    Full Text Available We used stable isotope analyses to characterise the feeding dynamics of a population of red swamp crayfish in Lake Naivasha, Kenya, after the crash of submerged macrophytes and associated macroinvertebrates, and during a natural draw-down of the lake water level. We expected a heavy reliance upon a diet of detrital matter to sustain the population as a consequence, and indeed, for the majority of the crayfish population caught from the lake, we saw a concomitant shift in isotopic values reflecting a dietary change. However, we also caught individual crayfish that had occupied the footprints of hippopotamus and effectively extended their range beyond the lake up to 40 m into the riparian zone. Isotopic analysis confirmed limited nocturnal observations that these individuals were consuming living terrestrial plants in the vicinity of the footprints. These are the first empirical data to demonstrate direct use of terrestrial resources by an aquatic crayfish species and further highlight the traits that make red swamp crayfish such opportunistic and successful invaders.

  16. DISTRIBUTION AND HABITAT REQUIREMENTS OF THE WHITE-CLAWED CRAYFISH, AUSTROPOTAMOBIUS PALLIPES, IN A STREAM FROM THE PAYS DE LOIRE REGION, FRANCE: AN EXPERIMENTAL AND DESCRIPTIVE STUDY

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    BROQUET T.

    2002-07-01

    Full Text Available A population of white-clawed crayfish (Austropotamobius pallipes was studied from January to October 2000 in a stream from the Pays de Loire region (Western France. An experimental modification of habitat was performed in four stream sections by providing refuges for crayfish, followed by a regular survey of population dynamics in these areas. The crayfish distribution along the brook was studied in relation to several parameters, including water quality, current speed, brook depth and presence of refuges for crayfish. Presence of hiding places was the only habitat parameter correlated with crayfish distribution along the stream whereas colonization process in modified sections was determined by sun exposure and current speed conditions. Despite a presumably high growth rate and its ability to reach locally important densities, the population appeared to be fragmented.

  17. Muddied waters: suspended sediment impacts on gill structure and aerobic scope in an endangered native and an invasive freshwater crayfish

    DEFF Research Database (Denmark)

    Rosewarne, P.J.; Svendsen, Jon Christian; Mortimer, R.J.G.

    2014-01-01

    Suspended sediment (SS) loadings in freshwater habitats have increased over the past century and SS is now a significant environmental stressor. Greater tolerance to environmental stressors has been proposed as a factor in the success of aquatic invasive species. Further, parasites may interact...... with environmental stressors to increase host susceptibility to loss of fitness and mortality. We compared the effects of SS exposure on the gill structure and aerobic scope of the endangered white-clawed crayfish (Austropotamobius pallipes), and the invasive signal crayfish (Pacifastacus leniusculus), and assessed...... impacts in relation to parasite burden. SS caused gill fouling and reduction in aerobic scope in both species, though A. pallipes was more susceptible than invasive P. leniusculus. The parasite Branchiobdella astaci, a crayfish worm that infests the gills, interacted with the sediment to affect gill...

  18. Can heat waves change the trophic role of the world's most invasive crayfish? Diet shifts in Procambarus clarkii.

    Science.gov (United States)

    Carreira, Bruno M; Segurado, Pedro; Laurila, Anssi; Rebelo, Rui

    2017-01-01

    In the Mediterranean basin, the globally increasing temperatures are expected to be accompanied by longer heat waves. Commonly assumed to benefit cold-limited invasive alien species, these climatic changes may also change their feeding preferences, especially in the case of omnivorous ectotherms. We investigated heat wave effects on diet choice, growth and energy reserves in the invasive red swamp crayfish, Procambarus clarkii. In laboratory experiments, we fed juvenile and adult crayfish on animal, plant or mixed diets and exposed them to a short or a long heat wave. We then measured crayfish survival, growth, body reserves and Fulton's condition index. Diet choices of the crayfish maintained on the mixed diet were estimated using stable isotopes (13C and 15N). The results suggest a decreased efficiency of carnivorous diets at higher temperatures, as juveniles fed on the animal diet were unable to maintain high growth rates in the long heat wave; and a decreased efficiency of herbivorous diets at lower temperatures, as juveniles in the cold accumulated less body reserves when fed on the plant diet. Heat wave treatments increased the assimilation of plant material, especially in juveniles, allowing them to sustain high growth rates in the long heat wave. Contrary to our expectations, crayfish performance decreased in the long heat wave, suggesting that Mediterranean summer heat waves may have negative effects on P. clarkii and that they are unlikely to boost its populations in this region. Although uncertain, it is possible that the greater assimilation of the plant diet resulted from changes in crayfish feeding preferences, raising the hypotheses that i) heat waves may change the predominant impacts of this keystone species and ii) that by altering species' trophic niches, climate change may alter the main impacts of invasive alien species.

  19. Can heat waves change the trophic role of the world's most invasive crayfish? Diet shifts in Procambarus clarkii.

    Directory of Open Access Journals (Sweden)

    Bruno M Carreira

    Full Text Available In the Mediterranean basin, the globally increasing temperatures are expected to be accompanied by longer heat waves. Commonly assumed to benefit cold-limited invasive alien species, these climatic changes may also change their feeding preferences, especially in the case of omnivorous ectotherms. We investigated heat wave effects on diet choice, growth and energy reserves in the invasive red swamp crayfish, Procambarus clarkii. In laboratory experiments, we fed juvenile and adult crayfish on animal, plant or mixed diets and exposed them to a short or a long heat wave. We then measured crayfish survival, growth, body reserves and Fulton's condition index. Diet choices of the crayfish maintained on the mixed diet were estimated using stable isotopes (13C and 15N. The results suggest a decreased efficiency of carnivorous diets at higher temperatures, as juveniles fed on the animal diet were unable to maintain high growth rates in the long heat wave; and a decreased efficiency of herbivorous diets at lower temperatures, as juveniles in the cold accumulated less body reserves when fed on the plant diet. Heat wave treatments increased the assimilation of plant material, especially in juveniles, allowing them to sustain high growth rates in the long heat wave. Contrary to our expectations, crayfish performance decreased in the long heat wave, suggesting that Mediterranean summer heat waves may have negative effects on P. clarkii and that they are unlikely to boost its populations in this region. Although uncertain, it is possible that the greater assimilation of the plant diet resulted from changes in crayfish feeding preferences, raising the hypotheses that i heat waves may change the predominant impacts of this keystone species and ii that by altering species' trophic niches, climate change may alter the main impacts of invasive alien species.

  20. Distribution and establishment of the alien Australian redclaw crayfish, Cherax quadricarinatus, in South Africa and Swaziland

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    Ana L. Nunes

    2017-04-01

    Full Text Available Background The Australian redclaw crayfish (Cherax quadricarinatus, von Martens, is native to Australasia, but has been widely translocated around the world due to aquaculture and aquarium trade. Mostly as a result of escape from aquaculture facilities, this species has established extralimital populations in Australia and alien populations in Europe, Asia, Central America and Africa. In South Africa, C. quadricarinatus was first sampled from the wild in 2002 in the Komati River, following its escape from an aquaculture facility in Swaziland, but data on the current status of its populations are not available. Methods To establish a better understanding of its distribution, rate of spread and population status, we surveyed a total of 46 sites in various river systems in South Africa and Swaziland. Surveys were performed between September 2015 and August 2016 and involved visual observations and the use of collapsible crayfish traps. Results Cherax quadricarinatus is now present in the Komati, Lomati, Mbuluzi, Mlawula and Usutu rivers, and it was also detected in several off-channel irrigation impoundments. Where present, it was generally abundant, with populations having multiple size cohorts and containing ovigerous females. In the Komati River, it has spread more than 112 km downstream of the initial introduction point and 33 km upstream of a tributary, resulting in a mean spread rate of 8 km year−1 downstream and 4.7 km year−1 upstream. In Swaziland, estimated downstream spread rate might reach 14.6 km year−1. Individuals were generally larger and heavier closer to the introduction site, which might be linked to juvenile dispersal. Discussion These findings demonstrate that C. quadricarinatus is established in South Africa and Swaziland and that the species has spread, not only within the river where it was first introduced, but also between rivers. Considering the strong impacts that alien crayfish usually have on invaded ecosystems

  1. The future of the indigenous freshwater crayfish Austropotamobius italicus in Basque Country streams: Is it possible to survive being an inconvenient species?

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    L. García-Arberas

    2009-01-01

    Full Text Available The white-clawed freshwater crayfish Austropotamobius italicus is listed as “vulnerable” in the Spanish Red List of threatened species, but local legislation varies among Spanish regions. Thus, while in some places the species is classified as “in risk of extinction” and various plans of conservation and restoration have been implemented, in the Basque Country and other regions the species is not listed. The distribution of the white-clawed crayfish in the province of Biscay (Basque Country was studied from 1993 to 2007 at more than 600 sampling locations. Results show that 108 streams were inhabited by the native crayfish species A. italicus while 137 streams were inhabited by non-native signal crayfish Pacifastacus leniusculus or red-swamp crayfish Procambarus clarkii. The spread of non-native crayfish is not the only threat to the native species whose survival is also closely dependent on how watersheds are managed. Most A. italicus populations inhabit headwaters, where forestry activities are very important. The presence of native crayfish in heavily forested areas results in a conflict of interests and makes its conservation particularly difficult. We employed a SWOT analysis – an assessment and decision tool commonly used in marketing and business – to evaluate the situation of the native white-clawed crayfish in Biscay, a province characterized by very high demographic pressure. SWOT analysis has proved to be a useful diagnostic tool and can help develop better and more accurate management strategies for the conservation of native crayfish threatened by multiple stressors.

  2. DISTRIBUTION, RECENT MORTALITIES AND CONSERVATION MEASURES OF CRAYFISH IN HELLENIC FRESH WATERS

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    KOUTRAKIS E.

    2007-04-01

    Full Text Available Freshwater crayfish are found in 20 out of 53 Prefectures of Greece (38% and they form isolated populations in relatively pristine water bodies. Three indigenous crayfish species (ICS occur in Greek waters: Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, as well as one non-indigenous crayfish species (NICS Pacifastacus leniusculus. Greece represents probably the most southern natural distribution limit for A. astacus and A. torrentium in the world. Concerning NICS, P. leniusculus was imported, at least in two cases, from Sweden and Germany during the early and late 1980’s respectively, in order to replace A. astacus stocks impoverished by human activities. Recently, Cherax quadricarinatus specimens have been seen in a restaurant’s aquarium and pet shop, raising fears about uncontrolled imports of alien pet species. During our 2004-2005 survey, we found that P. leniusculus established not only a thriving population in the artificial Lake Agra (Region of Central Macedonia, but also they co-occur with A. torrentium there. It is also suspected that A. astacus may co-occur there with these two species, as three large male specimens of A. astacus were caught in a creek close to the lake. Concerning A. leptodactylus, there are three sets of preserved samples from the River Evros (state border with Turkey in Thrace today, dated back to the 19th century, but no recent information about occurrence was available. But the accidental catch of six specimens of A. leptodactylus during May 2005 in that river re-documented the occurrence of the species. Finally, a deep-dwelling A. torrentium population with bluish legs was found to live in depths up to 7,800 meters inside the Aggitis Cave in northeastern Greece. There is a lot of work to be done on geographic distribution, population dynamics, genetics, reproduction, nutrition, diseases, and farming of crayfish species in Greece. Moreover, several actions should be undertaken to

  3. Infection status of Paragonimus westermani metacercariae in crayfish (Cambaroides similis) collected from Bogildo (Islet), Wando-gun, Chollanam-do, Korea

    Science.gov (United States)

    Min, Duk-Young

    1999-01-01

    During the period from October 1996 to November 1998, the infection status of Paragonimus westermani metacercariae in freshwater crayfish (Cambaroides similis) collected from Bogildo (islet), Wando-gun, Chollanam-do, which is known for an endemic area of P. westermani in Korea, were examined. The average infection rate of Paragonimus metacercariae in crayfish was 88.6%, and mean number of metacercariae per infected crayfish was 30.2. This metacercarial density was the highest in the group of weight in 7.1-9.0 g. These results suggest that the natural life cycle of P. westermani is still well-preserved in Bogildo. PMID:10188385

  4. Antibacterial properties of extracts of Solidago canadensis and their potential use as dietary supplements in red swamp crayfish (Procambarus clarkii

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    Manhong YE,Lei ZHANG,Jiaqi GE,Haifeng SUN,Jingjing NI,Shengmei YANG,Wanhong WEI

    2015-12-01

    Full Text Available Canadian goldenrod (Solidago canadensis is one of the most destructive invasive weeds in South-eastern China. To evaluate its potential application as dietary supplement in red swamp crayfish (Procambarus clarkii, the antibacterial properties of aqueous and ethanol extracts of this plant against three major pathogenic bacteria in crayfish aquaculture were examined. Inhibition zone tests and determination of minimum inhibitory concentration revealed that the extracts had lower antibacterial activity than extracts from two traditional medicinal plants that possess antibacterial properties, garlic (Allium sativum and cortex phellodendri (Phellodendron chinense. However, they did exhibit greater antibacterial effects than extracts from another widely used medicinal plant, Sophora flavescens, and an aquatic weed, Alternanthera philoxeroides. Aqueous extracts of Canadian goldenrod gave greater inhibition than the ethanol extracts. Crayfish fed a diet with 2% these aqueous extracts exhibited significantly higher enzyme activity of alkaline phosphatase, catalase and phenoloxidase (P<0.05. Based on the results of this study, we conclude that aqueous extracts of Canadian goldenrod are highly promising for the development of new dietary supplement for use in crayfish aquaculture.

  5. Mitochondrial DNA provides evidence of a double origin for the stone crayfish Austropotamobius torrentium in the Elbe basin

    Czech Academy of Sciences Publication Activity Database

    Petrusek, A.; Pešek, P.; Leština, Dan; Martin, P.; Fischer, D.; Kozák, P.; Vlach, P.

    2017-01-01

    Roč. 62, JAN 01 (2017), s. 77-83 ISSN 0075-9511 Institutional support: RVO:60077344 Keywords : stone crayfish * Austropotamobius torrentium * Elbe basin Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 1.427, year: 2016 https://www.sciencedirect.com/science/article/pii/S0075951116300901

  6. Additional supply of decapsulated Artemia cysts for various periods in intensive rearing of juvenile crayfish (Pacifastacus leniusculus, Astacidae

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    González Á.

    2011-06-01

    Full Text Available The additional supply of live feeds such as Artemia remains indispensable in juvenile astacid rearing from the start of independent life. Considering that cost and work could be reduced by restricting this supply, a 100-day experiment was carried out with stage 2 Pacifastacus leniusculus to evaluate the effects of different administration periods of decapsulted Artemia cysts as supplement to a dry diet at two stocking densities. Using a bifactorial design, six treatments differing in the time at which the cysts were withdrawn (after 20, 30 or 50 days of experiment and the stocking density (100 or 200 crayfish·m-2 were conducted. Survival rates did not show significant differences among groups, with final figures averaging 81%. Crayfish receiving cysts up to day 50 showed faster growth (around 13.8 mm carapace length and 610 mg weight at the end of the experiment than the rest, significant differences being recorded from day 60 of experiment onwards. The 20-day and 30-day supplies resulted in similar growth values. There were no significant differences in survival or growth between 100 and 200 crayfish·m-2. This study shows that decapsulated Artemia cysts can be withdrawn at day 20 (allowing to feed a dry diet as the sole food thereafter and that faster growth can be obtained if cysts are supplied up to day 50. Furthermore, a stocking density of 200 crayfish·m-2 can be advised under the mentioned feeding conditions.

  7. The Use of Fresh Cogongrass as Transportation Media with Level Dry System for Broodstock of Crayfish on Various Old Time

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    Ferdinand Hukama Taqwa

    2015-01-01

    Full Text Available The research was to determine the effect of the use of fresh cogongrass as media packaging filler on survival rate of broodstock of crayfish that transported with level dry system for 24, 48, dan 72 hours which randomized completely design experiment. The research preparation were media preparation of pond water, preparation of filler material and preparation of experimental animal (3 days adaptation after arrived from producer and starvation for 24 hours. The major research were anestetion of broodstock of crayfish with direct sock of low temperature at 12oC for ±5 minutes, transportation experiment of broodstock with fresh cogongrass as material filler. The result showed that the use of fresh cogongrass on various old time of dry level system has a significantly different to time of recovery and survival rate of broodstock of crayfish after tranforted. The fastest time of recovery was 89.55 seconds for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. The survival rate after tranported the highest was 98.89% for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. This research showed that the use of fresh cogongrass as material packaging filler of dry level system was still effective until 48 hours.Keywords: afresh cogongrass, broodstock of crayfish, various old time transportation, level dry system

  8. MANAGEMENT OF THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES IN WESTERN FRANCE: ABIOTIC AND BIOTIC FACTORS STUDY

    Directory of Open Access Journals (Sweden)

    TROUILHE M. C.

    2003-04-01

    Full Text Available In France, the distribution of the white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858, is restricted, fragmented and mainly located in headwaters. To preserve this indigenous species, it is necessary to characterize its ecological requirements (water and habitat quality. With this aim in view, a two-year study is being conducted in the Deux-Sèvres department (Western France since November 2002. Nine brooks from four different catchments are monitored regularly; eight of the nine brooks harbour whiteclawed crayfish populations. Two sampling sites are surveyed per brook, the first being where the crayfish population is located and the second 2 to 3 km downstream. Physicochemical parameters (18 are measured twice monthly and biotic factors are estimated twice yearly. In this study, the I.B.G.N. (Indice Biologique Global Normalisé protocol based on the determination of macroinvertebrates was used as a biotic index of biological water quality. Results of this preliminary study on two brooks (Thouet and Verdonnière show that physico-chemical and biological data considered separately do not provide reliable information about A. pallipes ecological requirements. However, the use of multivariate analyses (Principal Component Analysis to combine abiotic and biotic factors highlights a good correlation between these parameters. Organic matter appears to be a better discriminating factor than mineral matter affecting presence or absence of the whiteclawed crayfish.

  9. Functional aspects of cHH C-terminal amidation in crayfish species.

    Science.gov (United States)

    Mosco, Alessandro; Edomi, Paolo; Guarnaccia, Corrado; Lorenzon, Simonetta; Pongor, Sándor; Ferrero, Enrico A; Giulianini, Piero G

    2008-04-10

    The crustacean hyperglycemic hormone is the most abundant neuropeptide present in the eyestalk of Crustacea and its main role is to control the glucose level in the hemolymph. Our study was aimed at assessing the importance of C-terminal amidation for its biological activity. Two recombinant peptides were produced, Asl-rcHH-Gly with a free carboxyl terminus and Asl-rcHH-amide with an amidated C-terminus. Homologous bioassays performed on the astacid crayfish Astacus leptodactylus showed that the amidated peptide had a stronger hyperglycemic effect compared to the non-amidated peptide. To assess the relevance of amidation also in other decapods and how much the differences in the cHH amino acid sequence can affect the functionality of the peptides, we carried out heterologous bioassays on the cambarid Procambarus clarkii and palaemonid Palaemon elegans. The Asl-rcHH-amide elicited a good response in P. clarkii and in P. elegans. The injection of Asl-rcHH-Gly evoked a weak response in both species. These results prove the importance of C-terminal amidation for the biological activity of cHH in crayfish as well as the role of the peptide primary sequence for the species-specificity hormone-receptor recognition.

  10. Glutamate-mediated protection of crayfish glial cells from PDT-induced apoptosis

    Science.gov (United States)

    Rudkovskii, M. V.; Romanenko, N. P.; Berezhnaya, E. V.; Kovaleva, V. D.; Uzdensky, A. B.

    2011-03-01

    Photodynamic treatment that causes intense oxidative stress and kills cells is currently used in neurooncology. However, along with tumor it damages surrounding healthy neurons and glial cells. In order to study the possible role of glutamate-related signaling pathways in photodynamic injury of neurons and glia, we investigated photodynamic effect of alumophthalocyanine Photosens on isolated crayfish stretch receptor that consists of a single neuron surrounded by glial cells. The laser diode (670 nm, 0.4 W/cm2) was used for dye photoexcitation. Application of glutamate increased photodynamically induced necrosis of neurons and glial cells but significantly decreased glial apoptosis. The natural neuroglial mediator N-acetylaspartylglutamate, which releases glutamate after cleavage in the extracellular space by glutamate carboxypeptidase II, also inhibited photoinduced apoptosis. Inhibition of glutamate carboxypeptidase II, oppositely, enhanced apoptosis of glial cells. These data confirm the anti-apoptotic activity of glutamate. Application of NMDA or inhibition of NMDA receptors by MK801 did not influence photodynamic death of neurons and glial cells that indicated nonparticipation of NMDA receptors in these processes. Inhibition of metabotropic glutamate receptors by AP-3 decreased PDT-induced apoptosis. One can suggest that crayfish neurons naturally secrete NAAG, which being cleaved by GCOP produces glutamate. Glutamate prevents photoinduced apoptosis of glial cells possibly through metabotropic but not ionotropic glutamate receptors.

  11. Soluble guanylyl cyclase is involved in PDT-induced injury of crayfish glial cells

    Science.gov (United States)

    Kovaleva, V. D.; Uzdensky, A. B.

    2016-04-01

    Photodynamic therapy (PDT) is a potential tool for selective destruction of malignant brain tumors. However, not only malignant but also healthy neurons and glial cells may be damaged during PDT. Nitric oxide is an important modulator of cell viability and intercellular neuroglial communications. NO have been already shown to participate in PDT-induced injury of neurons and glial cells. As soluble guanylyl cyclase is the only known receptor for NO, we have studied the possible role of soluble guanylyl cyclase in the regulation of survival and death of neurons and surrounding glial cells under photo-oxidative stress induced by photodynamic treatment (PDT). The crayfish stretch receptor consisting of a single identified sensory neuron enveloped by glial cells is a simple but informative model object. It was photosensitized with alumophthalocyanine photosens (10 nM) and irradiated with a laser diode (670 nm, 0.4 W/cm2). Using inhibitory analysis we have shown that during PDT soluble guanylyl cyclase, probably, has proapoptotic and antinecrotic effect on the glial cells of the isolated crayfish stretch receptor. Proapoptotic effect of soluble guanylyl cyclase could be mediated by protein kinase G (PKG). Thus, the involvement of NO/sGC/cGMP/PKG signaling pathway in PDT-induced apoptosis of glial cells was indirectly demonstrated.

  12. Epigenetic regulation of death of crayfish glial cells but not neurons induced by photodynamic impact.

    Science.gov (United States)

    Sharifulina, S A; Komandirov, M A; Uzdensky, A B

    2014-03-01

    Epigenetic processes are involved in regulation of cell functions and survival, but their role in responses of neurons and glial cells to oxidative injury is insufficiently explored. Here, we studied the role of DNA methylation and histone deacetylation in reactions of neurons and surrounding glial cells to photodynamic treatment that induces oxidative stress and cell death. Isolated crayfish stretch receptor consisting of a single mechanoreceptor neuron surrounded by glial cells was photosensitized with aluminum phthalocyanine Photosens that induced neuron inactivation, necrosis of the neuron and glia, and glial apoptosis. Inhibitors of DNA methylation 5-azacytidine and 5-aza-2'-deoxycytidine (decitabine) reduced the level of PDT-induced necrosis of glial cells but not neurons by 1.3 and 2.0 times, respectively, and did not significantly influence apoptosis of glial cells. Histone deacetylase inhibitors valproic acid and trichostatin A inhibited PDT-induced both necrosis and apoptosis of satellite glial cells but not neurons by 1.6-2.7 times. Thus, in the crayfish stretch receptor DNA methylation and histone deacetylation are involved in epigenetic control of glial but not neuronal necrosis. Histone deacetylation also participates in glial apoptosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Structural alterations in the male reproductive system of the freshwater crayfish, Cherax quadricarinatus (Decapoda, Parastacidae).

    Science.gov (United States)

    Bugnot, Ana B; López Greco, Laura S

    2009-10-01

    No diseases affecting reproductive performance have been previously reported in freshwater crayfishes. This study aims to characterise one reproductive system abnormality found in males of Cherax quadricarinatus reared in captivity. Fifteen adult males of C. quadricarinatus (70-110 g) were purchased from San Mateo S.A. farm (Entre Ríos, Argentina) each season during 2007. Macroscopic analysis showed that 26.6% of the animals sacrificed in winter presented brownish distal vasa deferentia. Histological analysis showed different levels of structural abnormality in the epithelium of the vasa deferentia and spermatophore. Granular and hyaline haemocytes were identified within the vasa deferentia but no significant differences were found in the sperm count between normal and brownish vas deferens. Histological analysis of the crayfishes sacrificed in autumn also showed these modifications in 22% of the animals, however, they did not show the brownish colour under macroscopic analysis. The similarities between the male reproductive system syndrome in shrimps and the abnormalities found in C. quadricarinatus are notable. An unspecific response to thermic stress is a possible explanation of these structural alterations.

  14. Direct and indirect effects of an invasive omnivore crayfish on leaf litter decomposition.

    Science.gov (United States)

    Carvalho, Francisco; Pascoal, Cláudia; Cássio, Fernanda; Sousa, Ronaldo

    2016-01-15

    Invasive alien species (IAS) can disrupt important ecological functions in aquatic ecosystems; however, many of these effects are not quantified and remain speculative. In this study, we assessed the effects of the invasive crayfish Procambarus clarkii (Girard, 1852) on leaf litter decomposition (a key ecosystem process) and associated invertebrates using laboratory and field manipulative experiments. The crayfish had significant impacts on leaf decomposition due to direct consumption of leaf litter and production of fine particulate organic matter, and indirectly due to consumption of invertebrate shredders. The invertebrate community did not appear to recognize P. clarkii as a predator, at least in the first stages after its introduction in the system; but this situation might change with time. Overall, results suggested that the omnivore invader P. clarkii has the potential to affect detritus-based food webs through consumption of basal resources (leaf litter) and/or consumers. Recognizing that this IAS is widespread in Europe, Asia and Africa, and may attain high density and biomass in aquatic ecosystems, our results are important to develop strategies for improving stream ecosystem functioning and to support management actions aiming to control the invasive omnivore P. clarkii. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. High prevalence of multiple paternity in the invasive crayfish species, Procambarus clarkii

    Science.gov (United States)

    Yue, Gen Hua; Li, Jia Le; Wang, Chun Ming; Xia, Jun Hong; Wang, Gen Lin; Feng, Jian Bing

    2010-01-01

    Reproductive strategy is a central feature of the ecology of invasive species as it determines the potential for population increase and range expansion. The red swamp crayfish, Procambarus clarkii, has invaded many countries and caused serious problems in freshwater ecosystems. However, little is known about the effects of environmental conditions on crayfish paternity and offspring traits in the wild. We studied these reproductive characteristics of P. clarkii in wild populations from two different habitats (ponds and ditches) in three locations with different environmental conditions in China. Genotyping of 1,436 offspring and 30 mothers of 30 broods was conducted by using four microsatellites. An analysis of genotyping results revealed that gravid females were the exclusive mother of the progeny they tended. Twenty-nine of 30 mothers had mated with multiple (2-4) males, each of which contributed differently to the number of offspring in a brood. The average number of fathers per brood and the number of offspring per brood were similar (P > 0.05) among six sampling sites, indicating that in P. clarkii multiple paternity and offspring number per brood are independent of environmental conditions studied. Indirect benefits from increasing the genetic diversity of broods, male and sperm competition, and cryptic female choice are a possible explanation for the high level multiple paternity and different contribution of fathers to offspring in this species. PMID:20186292

  16. cDNA cloning of prophenoloxidase from the freshwater crayfish Pacifastacus leniusculus and its activation.

    Science.gov (United States)

    Aspán, A; Huang, T S; Cerenius, L; Söderhäll, K

    1995-02-14

    Prophenoloxidase (proPO), an enzyme that is the terminal component of the so-called proPO activating system, a defense and recognition system in crustaceans and insects, has been purified and cloned from a crayfish blood cell cDNA library. The deduced amino acid sequence codes for a polypeptide with a mass of 80,732 Da, which is close to 76 kDa, the apparent mass of the purified enzyme. proPO contains two copper atoms, and two putative copper-binding sites were found in the deduced amino acid sequence. Sequence comparisons show that these putative copper-binding sites are similar to the corresponding sites in arthropod hemocyanins and also, although the sequence similarities are less extensive, similar to tyrosinases from vertebrates and microorganisms. The purified enzyme is a typical tyrosinase because it hydroxylates monophenols and oxidizes o-diphenols but does not oxidize p-diphenols. If a homogeneous preparation of crayfish proPO were incubated with a homogeneous sample of the proPO activating enzyme, a serine proteinase, the cleavage of proPO by this trypsin-like enzyme was found to occur between Arg-176 and Thr-177.

  17. Effects of cadmium on the biochemical composition of the freshwater crayfish Procambarus clarkii (Girard, 1852)

    Energy Technology Data Exchange (ETDEWEB)

    Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

    1991-12-01

    Lake Albufera of Valencia (Spain) and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic residues. Among these residues include heavy metals which have been deposited from the many urban and waste waters in this area. The American red crayfish, Procambarus clarkii from Albufera Lake has high resistance to heavy metals. The authors have also found that P. clarkii shows a high capacity for cadmium accumulation in experimental conditions and natural conditions since crayfish collected in this area contained considerable amounts of cadmium in several tissues even after 15 days of depuration in clean water. Since the physiological changes that take place when organisms are exposed to sublethal levels of stress could include rate of feeding as well as respiration and excretion, the net result could be a change in energy available for growth and reproduction. In this work, the authors have studied the biochemical energy composition of hepatopancreas, muscle and gills of P. clarkii after short term sublethal exposure to cadmium.

  18. Modelling habitat requirements of white-clawed crayfish (Austropotamobius pallipes using support vector machines

    Directory of Open Access Journals (Sweden)

    Favaro L.

    2011-07-01

    Full Text Available The white-clawed crayfish’s habitat has been profoundly modified in Piedmont (NW Italy due to environmental changes caused by human impact. Consequently, native populations have decreased markedly. In this research project, support vector machines were tested as possible tools for evaluating the ecological factors that determine the presence of white-clawed crayfish. A system of 175 sites was investigated, 98 of which recorded the presence of Austropotamobius pallipes. At each site 27 physical-chemical, environmental and climatic variables were measured according to their importance to A. pallipes. Various feature selection methods were employed. These yielded three subsets of variables that helped build three different types of models: (1 models with no variable selection; (2 models built by applying Goldberg’s genetic algorithm after variable selection; (3 models built by using a combination of four supervised-filter evaluators after variable selection. These different model types helped us realise how important it was to select the right features if we wanted to build support vector machines that perform as well as possible. In addition, support vector machines have a high potential for predicting indigenous crayfish occurrence, according to our findings. Therefore, they are valuable tools for freshwater management, tools that may prove to be much more promising than traditional and other machine-learning techniques.

  19. Constraints upon the response of fish and crayfish to environmental flow releases in a regulated headwater stream network.

    Directory of Open Access Journals (Sweden)

    Edwin T Chester

    Full Text Available In dry climate zones, headwater streams are often regulated for water extraction causing intermittency in perennial streams and prolonged drying in intermittent streams. Regulation thereby reduces aquatic habitat downstream of weirs that also form barriers to migration by stream fauna. Environmental flow releases may restore streamflow in rivers, but are rarely applied to headwaters. We sampled fish and crayfish in four regulated headwater streams before and after the release of summer-autumn environmental flows, and in four nearby unregulated streams, to determine whether their abundances increased in response to flow releases. Historical data of fish and crayfish occurrence spanning a 30 year period was compared with contemporary data (electrofishing surveys, Victoria Range, Australia; summer 2008 to summer 2010 to assess the longer-term effects of regulation and drought. Although fish were recorded in regulated streams before 1996, they were not recorded in the present study upstream or downstream of weirs despite recent flow releases. Crayfish (Geocharax sp. nov. 1 remained in the regulated streams throughout the study, but did not become more abundant in response to flow releases. In contrast, native fish (Gadopsis marmoratus, Galaxias oliros, Galaxias maculatus and crayfish remained present in unregulated streams, despite prolonged drought conditions during 2006-2010, and the assemblages of each of these streams remained essentially unchanged over the 30 year period. Flow release volumes may have been too small or have operated for an insufficient time to allow fish to recolonise regulated streams. Barriers to dispersal may also be preventing recolonisation. Indefinite continuation of annual flow releases, that prevent the unnatural cessation of flow caused by weirs, may eventually facilitate upstream movement of fish and crayfish in regulated channels; but other human-made dispersal barriers downstream need to be identified and

  20. Trapping for invasive crayfish: comparisons of efficacy and selectivity of baited traps versus novel artificial refuge traps

    Directory of Open Access Journals (Sweden)

    Green Nicky

    2018-01-01

    Full Text Available Non-native crayfish can dominate the invertebrate biomass of invaded freshwaters, with their high ecological impacts resulting in their populations being controlled by numerous methods, especially trapping. Although baited funnel traps (BTs are commonly used, they tend to be selective in mainly catching large-bodied males. Here, the efficacy and selectivity of BTs were tested against an alternative trapping method based on artificial refuges (ARTs that comprised of a metal base with several tubes (refuges attached. The target species was signal crayfish Pacifastacus leniusculus in an upland river in southwest England. Trapping was completed in April to October over two consecutive years. In total, 5897 crayfish were captured, with 87% captured in ARTs. Comparison of the catch per unit effort (CPUE between the trapping methods in the same 24 hour periods revealed significantly higher CPUE in ARTs than of BTs. ARTs fished for 6 consecutive days had higher catches than both methods over 24 hours. Whilst catches in BTs were significantly dominated by males (1.49M:1F, the sex ratio of catches in ARTs was 0.99M:1F. The mean carapace length of crayfish was also significantly larger in BTs (43.2 ± 0.6 mm than in ARTs (33.6 ± 0.2 mm. Thus, ARTs had higher CPUE over 24 hour and 6 day periods versus BTs and also captured a greater proportion of smaller and female individuals. These results indicate that when trapping methods are deployed for managing invasions, the use of ARTs removes substantial numbers of crayfish of both sexes and of varying body sizes.

  1. New distributional records of the stygobitic crayfish Cambarus cryptodytes (Decapoda: Cambaridae) in the Floridan Aquifer System of southwestern Georgia

    Science.gov (United States)

    Fenolio, Dante B.; Niemiller, Matthew L.; Gluesenkamp, Andrew G.; Mckee, Anna; Taylor, Steven J.

    2017-01-01

    Cambarus cryptodytes (Dougherty Plain Cave Crayfish) is an obligate inhabitant of groundwater habitats (i.e., a stygobiont) with troglomorphic adaptations in the Floridan aquifer system of southwestern Georgia and adjacent Florida panhandle, particularly in the Dougherty Plain and Marianna Lowlands. Documented occurrences of Dougherty Plain Cave Crayfish are spatially distributed as 2 primary clusters separated by a region where few caves and springs have been documented; however, the paucity of humanly accessible karst features in this intermediate region has inhibited investigation of the species' distribution. To work around this constraint, we employed bottle traps to sample for Dougherty Plain Cave Crayfish and other groundwater fauna in 18 groundwater-monitoring wells that access the Floridan aquifer system in 10 counties in southwestern Georgia. We captured 32 Dougherty Plain Cave Crayfish in 9 wells in 8 counties between September 2014 and August 2015. We detected crayfish at depths ranging from 17.9 m to 40.6 m, and established new county records for Early, Miller, Mitchell, and Seminole counties in Georgia, increasing the number of occurrences in Georgia from 8 to 17 sites. In addition, a new US Geological Survey (USGS) Hydrologic Unit Code 8 (HUC8) watershed record was established for the Spring Creek watershed. These new records fill in the distribution gap between the 2 previously known clusters in Georgia and Jackson County, FL. Furthermore, this study demonstrates that deployment of bottle traps in groundwater-monitoring wells can be an effective approach to presence—absence surveys of stygobionts, especially in areas where surface access to groundwater is limited.

  2. Residue Analysis of 60 Pesticides in Red Swamp Crayfish Using QuEChERS with High-Performance Liquid Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    Song, Shuangyu; Zhu, Kechen; Han, Lijun; Sapozhnikova, Yelena; Zhang, Zihao; Yao, Wei

    2018-02-05

    In this study, a multi-residue analytical method using quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and dispersive solid-phase extraction (d-SPE) cleanup, followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), was investigated for rapid determination of 60 pesticide residues in whole crayfish and crayfish meat. The final method used 10 mL of acetonitrile for extraction, 3 g of NaCl for partitioning, and 50 mg of primary secondary amine for d-SPE cleanup. The method was validated at three spiking levels (10, 50, and 100 ng/g) using triphenyl phosphate as an internal standard and both gradient and isocratic HPLC elution. Under gradient conditions, satisfactory recoveries (70-120%) and relative standard deviations of ≤20% were achieved for 83 and 88% of pesticides in whole crayfish and crayfish meat, respectively. Matrix effects were estimated using both gradient and isocratic HPLC elution. To our knowledge, this is the first study involving multi-residue analysis of HPLC-amenable pesticides in crayfish and mantis shrimp. The final method was successfully applied for analysis of 11 crayfish and mantis shrimp samples from markets in China, and propamocarb (shrimps.

  3. Serotonin modulation of CHH secretion by isolated cells of the crayfish retina and optic lobe.

    Science.gov (United States)

    Escamilla-Chimal, Elsa G; Hiriart, Marcia; Sánchez-Soto, Ma Carmen; Fanjul-Moles, Maria Luisa

    2002-02-01

    The authors used the reverse hemolytic plaque assay to investigate whether single retinal and optic lobe cells of juvenile and adult crayfish secrete crustacean hyperglycemic hormone (CHH) and whether the secretion rate depends on extracellular serotonin (5-HT) concentration. Nearly 25% of individual retinal and optic lobe cells of juvenile and adult organisms secrete CHH in response to KCl depolarization. In this condition, CHH secretion increased as a function of 5-HT concentration. In both cases, the dose-response curve indicates two different populations of CHH-secreting cells. Juveniles showed a higher CHH secretion index than did adult organisms, demonstrating a developmental interstage variation of CHH secretion. The authors conclude that (1) retinal CHH-secreting cells correspond to a population of retinal tapetal cells and (2) optic lobe CHH-secreting cells correspond to two subpopulations of CHH of medulla terminalis-X organ.

  4. Isolation of crustecdysone (20R-hydroxyecdysone) from a crayfish (Jasus lalandei H. Milne-Edwards)

    Science.gov (United States)

    Horn, D. H. S.; Fabbri, S.; Hampshire, F.; Lowe, M. E.

    1968-01-01

    1. A small amount (2mg.) of crustecdysone, a moulting hormone of crustaceans, was isolated from 1 ton of crayfish waste. 2. The purification procedure used was developed with the aid of crustacean and insect bioassays. 3. CM-Sephadex was found to be superior to Sephadex and very effective for the chromatographic separation of crustecdysone from other non-ionic compounds. The higher efficiency of CM-Sephadex is attributed to the greater number of carboxyl groups available for hydrogen-bonding. 4. Reversed-phase chromatography, with butan-1-ol–cyclohexane mixtures as the stationary phase and water as the flowing phase, proved superior to countercurrent distribution with these solvents for the fractionation of purified extracts. 5. A second moulting hormone, deoxycrustecdysone, and the red-concentrating hormone were obtained in a partially purified form. PMID:5685865

  5. Interdisciplinarity to reconstruct historical introductions: solving the status of cryptogenic crayfish.

    Science.gov (United States)

    Clavero, Miguel; Nores, Carlos; Kubersky-Piredda, Susanne; Centeno-Cuadros, Alejandro

    2016-11-01

    Anciently introduced species can be confounded with native species because introduction pre-dates the first species inventories or because of the loss of the collective memory of the introductions. The term 'cryptogenic species' denotes species of unknown or unclear status (native versus non-native) in a given territory, and disciplinary approaches are often insufficient for solving their true status. Here, we follow an integrative, multidisciplinary approach to solve the status of a cryptogenic species, proposing that building on evidence from multiple disciplines can produce robust and clarifying insights. We undertook an exhaustive review of information on a putatively native crayfish (Austropotamobius italicus) in Spain. The reviewed information included taxonomy, genetics and phylogeography, history, archaeology, linguistics, biogeography, ecology, symbiotic organisms and even gastronomy and pharmacy. The knowledge produced by different scientific disciplines converges to indicate that A. italicus is a non-native species in Spain. Historical documents even identify the first introduction event: crayfish were shipped from Italy to Spain in 1588 as a diplomatic gift from Francesco I de' Medici to King Philip II of Spain. Previous discussions on the status of A. italicus focussed on inconclusive and often confusing genetic results and excluded the rich and clarifying evidence available from other approaches and disciplines. Interdisciplinarity is an often-invoked but rarely implemented practice in an academic environment that increasingly promotes narrow-focussed specialization. Our review shows that the integration of disciplines can surpass disciplinary approaches in solving scientific controversies. Our results have straightforward implications for strategies to conserve biological diversity in Spain and Europe, urging a debate on the appropriateness of devoting conservation efforts to non-native species. © 2015 Cambridge Philosophical Society.

  6. Burrowing activity in channel levees: impact of the invasive red swamp crayfish Procambarus clarkii

    Science.gov (United States)

    Solari, L.; Bendoni, M.; Consumi, L.; Haubrock, P.; Inghilesi, A.; Mazza, G.; Torrini, M.; Tricarico, E.

    2016-12-01

    The effect of animal burrowing, as an example of bioturbation on the stability of river levees has been recently raised to the scientific community as a consequence of the levee collapses of Secchia and Foenna rivers in Italy (Camici et al., 2010, 2014; Orlandini et al., 2015). Indeed, these authors showed that the presence of animal burrows is crucial in promoting the collapse of the bank. The American red swamp Crayfish Procambarus clarkii is an invasive species in Europe, mostly introduced for commercial purposes related to livestock. It is rapidly spreading throughout the Italian peninsula due to its plasticity, dispersal capability and high reproduction rate (Souty-Grosset et al., 2016). As well as the negative effects on local biodiversity, it damages the levees of the irrigation channel leading to disastrous collapses, relevant repairing and maintenance costs. In this work, we present an experimental activity where specimens of P. clarkii were monitored while burrowing into a small-scale physical model of an earthen levee, coupled with the mathematical modelling of the variations induced by the burrows on the seepage flow patterns through the levee.Preliminary results show the burrowing structure was quite irregular. Generally, crayfish start burrowing under the water level, developing tunnels (diameter ranging 4-7cm) both horizontally and heading upward, also above the water level. Some tunnels showed one or more circular chambers. The highest burrowing activity was observed during the experiments carried out in summer, when the species has a peak of maximum activity due to the higher temperature. Mathematical modelling shows that, for given boundary conditions and experimental duration, the presence of burrows in the levee raises the phreatic line. Critical conditions for levee integrity may be associated either to the internal erosion and stability of the system of tunnels and to the emergence of the phreatic line of the landside of the levee slope. These

  7. Astaxanthin from Crayfish (Procambarus clarkii as a Pigmentary Ingredient in the Feed of Laying Hens

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    Garrido-Fernández, J.

    2008-06-01

    Full Text Available Chicken egg yolks generally owe their color to yellow carotenoids. The addition of synthetic red pigments allows changes in color, from the original yellow to red hues which may be more appealing to consumers in certain markets.Our aim has been to test whether ground crayfish shells, which are a rich and natural source of astaxanthin, produce detectable changes in the coloration of egg yolks through the accumulation of this carotenoid. Laying hens were fed with a commercial feed mixed with crayfish powder and the carotenoid profiles of the yolks in the eggs laid during the trial were monitored by HPLC. The analyses showed a progressive increase in the astaxanthin concentration in the egg yolks, reaching similar levels to those obtained for the rest of present carotenoid pigments.La yema de huevo de gallina debe su coloración a la presencia de carotenoides de tonalidad amarilla. La adición de colorantes sintéticos de tonalidades rojas permite modificar e incrementar la coloración de la yema desde el amarillo original a tonos rojos que pueden ser demandados en ciertos mercados según las preferencias del consumidor. El objetivo del trabajo fue probar si un triturado obtenido a partir de caparazones de cangrejo, que es una fuente natural y rica en astaxanteno, produce cambios detectables en la coloración de la yema de huevo por la acumulación de dicho carotenoide. Las gallinas ponedoras se alimentaron con un pienso comercial al que se adicionó triturado de caparazón de cangrejo. Se realizó un seguimiento de los cambios en la composición carotenoide (mediante HPLC de la yema de los huevos puestos durante el periodo de alimentación suplementada. Los análisis mostraron una progresiva incorporación de astaxanteno que alcanzó niveles similares al resto de carotenoides presentes inicialmente en la yema.

  8. Assessment of a cricket, Acheta domesticus, bioassay for Chequa Iflavirus and bunya-like virus from redclaw crayfish Cherax quadricarinatus.

    Science.gov (United States)

    Sakuna, Kitikarn; Elliman, Jennifer; Owens, Leigh

    2017-11-01

    Chequa iflavirus and a bunya-like virus infect redclaw crayfish (Cherax quadricarinatus) and they may cause mortality reaching 20-40% after about three weeks after a stress event. To complete River's postulates for viruses, virus-free animals are needed. Due to a lack of chequa iflavirus and bunya-like virus-free crayfish (testing shows>85% infection rate) coupled with the facts that iflavirus and bunyaviruses are found in insects and that crickets had been successful alternate hosts for crustacean viruses before, Acheta domesticus was trialled asa bioassay animal. There was no significant difference (P>0.05) in mortality rates between uninfected control crickets and infected crickets. Reverse transcriptase polymerase chain reaction for both viruses failed to find any trace of the RNA viruses in fed or inoculated crickets after 30days. The search for an alternative bioassay host will have to be widened. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. CRAYFISH PREDATION ON TADPOLES : A COMPARISON BETWEEN A NATIVE (AUSTROPOTAMOBIUS PALLIPES AND AN ALIEN SPECIES (PROCAMBARUS CLARKII.

    Directory of Open Access Journals (Sweden)

    GHERARDI F.

    2001-04-01

    Full Text Available In the laboratory, the motivation and/or ability to prey on anuran larvae (Bufo bufo, Rana kl. esculenta and R. italica were compared between a native European (Austropotamobius pallipes and an alien North American crayfish species (Procambarus clarkii. Both were skilled predators of tadpoles, adopting a sit-and-wait strategy. However, because P. clarkii displayed lower latency times in the presence of one of the three amphibians (Rana kl. esculenta here tested, the hypothesis is raised that invasive crayfish are more opportunistic predators and possibly faster in switching to different prey than those species they are displacing. From a conservation perspective, these preliminary results further emphasise the importance of studies centred on the invasion-displacement dichotomy.

  10. The paradox of the long-term positive effects of a North American crayfish on a European community of predators.

    Science.gov (United States)

    Tablado, Zulima; Tella, José L; Sánchez-Zapata, José A; Hiraldo, Fernando

    2010-10-01

    Invasions of non-native species are one of the major causes of losses of native species. In some cases, however, non-natives may also have positive effects on native species. We investigated the potential facilitative effects of the North American red swamp crayfish (Procambarus clarkii) on the community of predators in southwestern Spain. To do so, we examined the diets of predators in the area and their population trends since introduction of the crayfish. Most predator species consumed red swamp crayfish, which sometimes occurred in over 50% of their diet samples. Moreover, the abundance of species preying on crayfish increased significantly in the area as opposed to the abundance of herbivores and to predator populations in other areas of Europe, where those predators are even considered threatened. Thus, we report the first case in which one non-native species is both beneficial because it provides prey for threatened species and detrimental because it can drive species at lower trophic levels to extinction. Increases in predator numbers that are associated with non-native species of prey, especially when some of these predators are also invasive non-natives, may increase levels of predation on other species and produce cascading effects that threaten native biota at longer temporal and larger spatial scales. Future management plans should include the complexity of interactions between invasive non-natives and the entire native community, the feasibility of successful removal of non-native species, and the potential social and economic interests in the area. © 2010 Society for Conservation Biology.

  11. EVALUATION OF THE AMERICAN WATERWEED (ELODEA CANADENSIS MICHX. AS SUPPLEMENTAL FOOD FOR THE NOBLE CRAYFISH, ASTACUS ASTACUS

    Directory of Open Access Journals (Sweden)

    D’AGARO E.

    2004-01-01

    Full Text Available We conducted a preliminary study to evaluate the capacity of summerling Astacus astacus to consume the American waterweed (Elodea canadensis Michx..under artificial rearing conditions. Summerling A. astacus (initial b.w.: 0.32 ± 0.02 g were cultured (50 crayfish/m2 in 600l tanks for 89 days. The experimental design was composed of three treatments as follows: control diet (D (crude protein: 40.9% DM; ether extract: 7.4% DM, elodea (E (crude protein: 25.8% DM; ether extract: 1.4% DM and control diet + elodea (D + E with three replicates per treatment. Temperature, dissolved oxygen, and other water parameters were measured weekly (T: 20.1°C; O2: 7.2 mg/l; pH: 7.5; N-NH4: 0.05 mg/l; N-NO2: 0.01 mg/l; N-NO3: 29.9 mg/l. The relative growth rate was significantly (P < 0.01 higher in treatment D + E (195% and D (143% than in E (65%. The reduced growth observed in crayfish fed elodea only can probably be due to the lower dietary lipid level of the plant respect to the standard crayfish requirements. At the end of the experiment, the survival rate of A. astacus was higher (P < 0.05 for the treatment D + E (87% and D (81%, compared to E (56%. Our results suggest that E. canadensis can be used as a non-expensive supplemental food in order to increase growth and survival in summerling noble crayfish. They also showed that A. astacus has the potential to consume this macrophyte in nature.

  12. CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

    OpenAIRE

    REYNOLDS J. D.; DONOHOE R.

    2001-01-01

    The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet) occur in these systems, Dreissena has not yet colonized sites with large crayf...

  13. Control of motor activity in crayfish by the steroid hormone 20-hydroxyecdysone via motoneuron excitability and sensory-motor integration.

    Science.gov (United States)

    Bacqué-Cazenave, Julien; Bouvet, Flora; Fossat, Pascal; Cattaert, Daniel; Delbecque, Jean Paul

    2013-05-15

    We studied the effects of the molting hormone 20-hydroxyecdysone (20E) on leg sensory-motor networks of the red swamp crayfish, Procambarus clarkii. The hormone was injected in isolated crayfish and network activity was analyzed 3 days after injection using electrophysiology on an in vitro preparation of the leg locomotor network. This 20E treatment deeply reduced motor activity, by affecting both intrinsic motoneuron (MN) properties and sensory-motor integration. Indeed, we noticed a general decrease in motor nerve tonic activities, principally in depressor and promotor nerves. Moreover, intracellular recordings of depressor MNs confirmed a decrease of MN excitability due to a drop in input resistance. In parallel, sensory inputs originating from a proprioceptor, which codes joint movements controlled by these MNs, were also reduced. The shape of excitatory post-synaptic potentials (PSPs) triggered in MNs by sensory activity of this proprioceptor showed a reduction of polysynaptic components, whereas inhibitory PSPs were suppressed, demonstrating that 20E acted also on interneurons relaying sensory to motor inputs. Consequently, 20E injection modified the whole sensory-motor loop, as demonstrated by the alteration of the resistance reflex amplitude. These locomotor network changes induced by 20E were consistent with the decrease of locomotion observed in a behavioral test. In summary, 20E controls locomotion during crayfish premolt by acting on both MN excitability and sensory-motor integration. Among these cooperative effects, the drop of input resistance of MNs seems to be mostly responsible for the reduction of motor activity.

  14. The effect of sensory feedback on crayfish posture and locomotion: II. Neuromechanical simulation of closing the loop.

    Science.gov (United States)

    Bacqué-Cazenave, Julien; Chung, Bryce; Cofer, David W; Cattaert, Daniel; Edwards, Donald H

    2015-03-15

    Neuromechanical simulation was used to determine whether proposed thoracic circuit mechanisms for the control of leg elevation and depression in crayfish could account for the responses of an experimental hybrid neuromechanical preparation when the proprioceptive feedback loop was open and closed. The hybrid neuromechanical preparation consisted of a computational model of the fifth crayfish leg driven in real time by the experimentally recorded activity of the levator and depressor (Lev/Dep) nerves of an in vitro preparation of the crayfish thoracic nerve cord. Up and down movements of the model leg evoked by motor nerve activity released and stretched the model coxobasal chordotonal organ (CBCO); variations in the CBCO length were used to drive identical variations in the length of the live CBCO in the in vitro preparation. CBCO afferent responses provided proprioceptive feedback to affect the thoracic motor output. Experiments performed with this hybrid neuromechanical preparation were simulated with a neuromechanical model in which a computational circuit model represented the relevant thoracic circuitry. Model simulations were able to reproduce the hybrid neuromechanical experimental results to show that proposed circuit mechanisms with sensory feedback could account for resistance reflexes displayed in the quiescent state and for reflex reversal and spontaneous Lev/Dep bursting seen in the active state. Copyright © 2015 the American Physiological Society.

  15. EFFECTS OF RATION SIZE AND TEMPERATURE ON MOULT INCREMENT AND METABOLIC PARAMETERS OF JUVENILE NOBLE CRAYFISH, ASTACUS ASTACUS

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    RENAI B.

    2007-07-01

    Full Text Available A laboratory experiment was carried out to test the combined effects of ration size (1 vs 3% body weight, b.w. and temperature (15 ± 2 vs 22 ± 2 °C on moult increment and metabolic parameters of 80 juvenile noble crayfish (Astacus astacus. The maximum daily consumption (Cmax and respiration rate (R were used to calculate the growth scope (i.e. the difference between maximum daily energy consumption and energy costs at a given temperature. The conversion of R into a food-equivalent unit allowed the comparison with Cmax. Results showed that crayfish obtained the maximum moult increment when fed 3% b.w. while temperature seemed to play a less relevant role on growth rate per moult, affecting only the moulting frequency. Crayfish A. astacus fed ad libitum showed a relative insensitivity to the metabolic parameters (oxygen uptake, R and Cmax within the analysed range of temperatures, possibly as a reflection of this “species” distribution across a broad variety of habitats with different thermal regimes. In the present study, A. astacus displayed characteristics proper of a K-selected species, as slow to moderate growth.

  16. EVALUATION OF THE TOXICITY OF SYNTHETIC PYRETHROIDS TO RED SWAMP CRAYFISH (PROCAMBARUS CLARKII, GIRARD 1852 AND COMMON CARP (CYPRINUS CARPIO, L. 1758

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    MOROLLI C.

    2006-01-01

    Full Text Available The acute toxicity of three synthetic pyrethroids (Cypermethrin, Deltamethrin and Cyfluthrin to red swamp crayfish (Procambarus clarkii and the mortality after long-term exposition of young common carp to Deltamethrin were determined in standardized laboratory tests. The aim of this study was to evaluate the possibility of limiting the expansion of crayfish by the use of these compounds and the implications of their use on fish. Red swamp crayfish experienced high sensitivity to pyrethroids as expressed by the LC50-24h: 0.14 μg/l for Cypermethrin, 0.17 μg/l for Cyfluthrin and 0.22 μg/l for Deltamethrin. No mortality was observed in common carp during the long term (24 days exposure test at initial concentration of 22.0 μg/l of Deltamethrin. The concentrations of Deltamethrin in muscle of crayfish and common carp were under the limit of quantification of the gas-chromatographic method in all the tests. The results suggest that synthetic pyrethroids may be suitable to control or to eradicate nuisance populations of red swamp crayfish, in small and limited areas.

  17. Involvement of the crustacean hyperglycemic hormone (CHH) in the physiological compensation of the freshwater crayfish Cherax quadricarinatus to low temperature and high salinity stress.

    Science.gov (United States)

    Prymaczok, Natalia C; Pasqualino, Valeria M; Viau, Verónica E; Rodríguez, Enrique M; Medesani, Daniel A

    2016-02-01

    This study was aimed at determining the role of the crustacean hyperglycemic hormone (CHH) in the physiological compensation to both saline and thermal stress, in the freshwater crayfish Cherax quadricarinatus. By determining the expression of the CHH gene in the eyestalk of juvenile crayfish, we found that maximal induction of CHH was induced at high salinity (10 g/L) and low temperature (20 °C). In order to investigate the role of CHH in the physiological compensation to such stressful conditions, recombinant CHH was supplied to stressed animals. CHH-injected crayfish showed increased hemolymphatic levels of glucose, in accordance with a significant utilization of glycogen reserves from the hepatopancreas. Furthermore, CHH administration allowed stressed animals to regulate hemolymphatic sodium and potassium at more constant levels than controls. Taken together, these results suggest a relevant role of CHH in increasing the energy available intended for processes involved in the physiological compensation of C. quadricarinatus to both saline and thermal stress.

  18. Bullfrog tadpole (Rana catesbeiana) and red swamp crayfish (Procambarus clarkii) predation on early life stages of endangered razorback sucker (Xyrauchen texanus)

    Science.gov (United States)

    Mueller, G.A.; Carpenter, J.; Thornbrugh, D.

    2006-01-01

    Bullfrog tadpoles (Rana catesbeiana) and red swamp crayfish (Procambarus clarkii) are widespread introduced taxa that are problematic throughout the western United States. Their impact on native amphibians and crustaceans is well documented, but less is known regarding their influence on native fishes. Predator-prey tank tests showed both species consumed eggs and larvae of the endangered razorback sucker (Xyrauchen texanus) in a laboratory setting. Tadpoles consumed 2.2 razorback sucker eggs/d and 1.4 razorback sucker larvae/d, while crayfish ate 6.0 eggs/d and 3.5 larvae/d. Relatively high densities of bullfrog tadpoles and crayfish in razorback sucker spawning areas suggest that these nonnative taxa might pose a threat to the recruitment success of this and other imperiled native fish.

  19. Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard)

    Energy Technology Data Exchange (ETDEWEB)

    Del Ramo, J.; Diaz-Mayans, J.; Torreblanca, A.; Nunez, A.

    1987-05-01

    Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albufera and in the surrounding rice fields. Without adequate sanitary control, the crayfish is presently being fished commercially for human consumption. The purpose of the present study is to evaluate the degree of toxicity of various heavy metals (chromium, cadmium and mercury) to freshwater crayfish Procambarus clarkii at various temperatures.

  20. A model of co-occurrence: segregation and aggregation patterns in the mycoflora of the crayfish Procambarus clarkii in Lake Trasimeno (central Italy

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    Antonia C. Elia

    2012-01-01

    Full Text Available Although attention on crayfish diseases has recently proliferated, the focus is mainly on a single host-parasite relationship rather than analyzing the entire mycoflora, probably due to the fact that (1 some diseases are occasional (pathogens of which are of difficult collection and (2 economic impact is more relevant in aquaculture (i.e., a controlled environment where only few parasites occur than in natural conditions. Contrary to this viewpoint, fungal ectoparasites assume a great importance since they are integral components in shaping community, ecosystem structure, and energy flow. Here we described the fungal species co-occurrence patterns (species segregation/ aggregation using null models comparing the occurrence frequencies of ectosymbiots through host individuals with those expected by chance. Non-indigenous crayfish species like Procambarus clarkii allow to observe phenomena of competitive exclusion (segregation or mutualism (aggregation amongst fungi. We analyzed the fungal species occurrence on 86 host crayfish monthly collected from June 2007 to June 2008 in the Lake Trasimeno (Central Italy. A total of 29 fungal taxa were detected. Taxa showed a particular fungal assemblage with a great species variation depending on sampling month and crayfish sex, size, and body region. In particular, fungal species showed different occurrence patterns in both richness and segregation/ aggregation. The fungal community shows a non-random structure not in all cases, with the majority of tests indicating segregation, not aggregation of ectosymbiontic species on hosts. The non-random patterns of fungal co-occurrence in some cases suggest that some temporally or spatially variable factors are responsible for the establishment of the mycoflora community assemblage. We also detected temporal differences in fungal co-occurrences patterns. Regarding seasonal samples, the same analyses showed a competitive structure only in the sub-communities found on

  1. Photodynamic injury of isolated crayfish neuron and surrounding glial cells: the role of p53

    Science.gov (United States)

    Sharifulina, S. A.; Uzdensky, A. B.

    2015-03-01

    The pro-apoptotic transcription factor p53 is involved in cell responses to injurious impacts. Using its inhibitor pifithrin- α and activators tenovin-1, RITA and WR-1065, we studied its potential participation in inactivation and death of isolated crayfish mechanoreceptor neuron and satellite glial cells induced by photodynamic treatment, a strong inducer of oxidative stress. In dark, p53 activation by tenovin-1 or WR-1065 shortened activity of isolated neurons. Tenovin-1 and WR-1065 induced apoptosis of glial cells, whereas pifithrin-α was anti-apoptotic. Therefore, p53 mediated glial apoptosis and suppression of neuronal activity after axotomy. Tenovin-1 but not other p53 modulators induced necrosis of axotomized neurons and surrounding glia, possibly, through p53-independent pathway. Under photodynamic treatment, p53 activators tenovin-1 and RITA enhanced glial apoptosis indicating the pro-apoptotic activity of p53. Photoinduced necrosis of neurons and glia was suppressed by tenovin-1 and, paradoxically, by pifithrin-α. Modulation of photoinduced changes in the neuronal activity and necrosis of neurons and glia was possibly p53-independent. The different effects of p53 modulators on neuronal and glial responses to axotomy and photodynamic impact were apparently associated with different signaling pathways in neurons and glial cells.

  2. Crayfish chitosan for microencapsulation of coriander (Coriandrum sativum L.) essential oil.

    Science.gov (United States)

    Duman, Fatih; Kaya, Murat

    2016-11-01

    In this study, chitosan, which was obtained from the waste shells of crayfish (Astacus leptodactylus), was used for the encapsulation of the essential oil isolated from coriander (Coriandrum sativum L.) via the spray drying method. The obtained capsules were characterized using SEM, FT-IR, TGA and XRD. The size of the microcapsules was between 400nm - 7μm. It was determined that the swelling characteristic of the capsules was pH sensitive. The release showed bi-phasic characteristics and the maximum degree was reached after 72h. Antimicrobial activity studies showed that pure chitosan more effective than the capsule. The antioxidant activity was recorded concentration-dependent. In contrast the antimicrobial activity, antioxidant activity of the capsule was found much higher than the oil and the pure chitosan. Consequently, it was determined that this product could be used in the food and pharmaceutical industries as a natural antioxidant and antimicrobial agent. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Characterization of Population Genetic Structure of red swamp crayfish, Procambarus clarkii, in China.

    Science.gov (United States)

    Yi, Shaokui; Li, Yanhe; Shi, Linlin; Zhang, Long; Li, Qingbin; Chen, Jing

    2018-04-03

    The red swamp crayfish (Procambarus clarkii) is one of the most economically important farmed aquatic species in China. However, it is also a famous invasive species in the world. This invasive species was dispersed most via human activities including intentional or unintentional carry in China. Thus, P. clarkii naturally distributed in China provides us a desirable mode to investigate the genetic structure of an invasive species dispersed mainly by human-mediated factors. To reveal the impact of human-mediated dispersal on genetic structure of P. clarkii in China, a total of 22,043 genome-wide SNPs were obtained from approximately 7.4 billion raw reads using 2b-RAD technique in this study. An evident pattern of population genetic structure and the asymmetrical migrational rates between different regions were observed with 22 populations based on these SNPs. This study provide a better understanding of the population genetic structure and demographic history of P. clarkii populations in China, inferring that anthropogenic factors (aquaculture or by accident) and ecological factors (e.g., complicated topography and climatic environment), as well as its special biological traits could account for the current population structure pattern and dispersal history of P. clarkii.

  4. A large discoidal lipoprotein present in only one of two closely related crayfish.

    Science.gov (United States)

    Stieb, Stefanie; Hoeger, Ulrich; Schenk, Sven

    2008-08-01

    The hemolymph lipoproteins of two European freshwater crayfish, Astacus astacus and Astacus leptodactylus, were isolated and characterized. The former species possesses two sex-independent lipoproteins, which can be related to the formerly described high-density lipoprotein (HDL)/beta-glucan binding protein and very high-density lipoprotein/clotting protein from other crustaceans. The latter species, however, contains an additional third lipoprotein with a unique structure. It is a large discoidal HDL with a diameter of 42 nm, a thickness of 7 nm and a density of 1.1 g/ml. SDS-PAGE revealed two different apolipoproteins with molecular masses of 240 and 85 kDa, respectively, arranged in a 1:1 stoichiometry as judged from cross linking experiments. The lipid content of this lipoprotein was 67%, far higher than in every other crustacean lipoprotein described so far. The native molecular mass of this HDL-type lipoprotein was estimated to be about 930 kDa. The lipid content of the other lipoproteins ranged between 25 and 30% for the HDL/beta-glucan binding protein and 6-8% for the VHDL/clotting protein.

  5. Muscle receptor organs in the crayfish abdomen: a student laboratory exercise in proprioception.

    Science.gov (United States)

    Leksrisawat, Bonnie; Cooper, Ann S; Gilberts, Allison B; Cooper, Robin L

    2010-11-18

    The primary purpose of this experiment is to demonstrate primary sensory neurons conveying information of joint movements and positions as proprioceptive information for an animal. An additional objective of this experiment is to learn anatomy of the preparation by staining, dissection and viewing of neurons and sensory structures under a dissecting microscope. This is performed by using basic neurophysiological equipment to record the electrical activity from a joint receptor organ and staining techniques. The muscle receptor organ (MRO) system in the crayfish is analogous to the intrafusal muscle spindle in mammals, which aids in serving as a comparative model that is more readily accessible for electrophysiological recordings. In addition, these are identifiable sensory neurons among preparations. The preparation is viable in a minimal saline for hours which is amenable for student laboratory exercises. The MRO is also susceptible to neuromodulation which encourages intriguing questions in the sites of modulatory action and integration of dynamic signals of movements and static position along with a gain that can be changed in the system.

  6. Food-rewarded conditioning and neurophysiological analysis of cheliped gripping behavior in crayfish.

    Science.gov (United States)

    Takahashi, Naomi; Takahata, Masakazu

    2017-10-15

    Animals act on their environment to intentionally manipulate it with a defined purpose. This behavior generally needs a special organ suited for the purpose and a highly complex neural mechanism to perform voluntary motor control. Crustaceans with a pair of chelipeds show various manipulative behavior for dietary, exploratory, and reproductive purposes, but the neuronal mechanism underlying the cheliped manipulative behavior has not been clarified yet. In the present study, we trained crayfish Procambarus clarkii to perform a cheliped manipulative task by a newly developed operant paradigm in which animals gripped a specific object for food reward when a visual cue was presented. Animals were then tethered in an operant chamber during the task to enable reliable physiological recordings from the central nervous system. Neural activities descending from the brain were recorded extracellularly from the connective nerves between the brain and the subesophageal ganglion in the trained animals. We found those units showing spike activities that were significantly correlated with cheliped muscle activities, but not with strict timing of visual cue presentation. Although we could not test if those descending activities were necessary or sufficient for initiating the cheliped action by their selective stimulation, the present findings suggest that neural activities for controlling operant gripping behavior are formulated in the brain rather than in the subesophageal ganglion where cheliped motoneurons are present and visual information is transmitted through the brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Biomagnification of some heavy and essential metals in sediments, fishes and crayfish from Ondo State coastal region, Nigeria

    International Nuclear Information System (INIS)

    Asaolu, S.S.; Olaofe, O.

    2005-01-01

    The bio magnifications levels of some essential (Fe, Zn, Cu) and toxic metals (Pb, Ni, Cd, Cr, Co, Mn) were determined in sediments, three kinds of fish (Oreochromis niloticus, Synodonthis sp., and Clarias gariepinus) and crayfish from the Ondo State coastal region. The metal bio magnification in the fish and crayfish was several times greater than in water, while that in the sediments was several thousand-folds greater than in both the organisms and water. Among the metals examined in water, Fe was the most abundant with average values of 146.7 and 74.3 mg/1, respectively, for wet and dry seasons, while Co was the least with average values of 2.4 and 1.6 mg/1. In the sediments, concentrations of Pb, Ni, Fe, Cr, Co and Mn in the wet season were relatively higher than those obtained for the dry season. Fe with an average of 50.9 mg/kg in C, gariepinus was the most abundant metal in the fish samples, while Cu with an average value of 0.3 mg/kg in O. niloticus was the least. The metal bio magnification for most of the metals for both seasons was found to vary widely from one location to the other. This was confirmed by the coefficient of variation that ranged from 31% to 144% and 29% to 130% in the wet and dry seasons, respectively. The present study has shown that fish, crayfish and sediments can be used to monitor the pollution level of metals in the Nigerian coastal water. (author)

  8. Capture efficiency and size selectivity of sampling gears targeting red-swamp crayfish in several freshwater habitats

    Directory of Open Access Journals (Sweden)

    Paillisson J.-M.

    2011-05-01

    Full Text Available The ecological importance of the red-swamp crayfish (Procambarus clarkii in the functioning of freshwater aquatic ecosystems is becoming more evident. It is important to know the limitations of sampling methods targeting this species, because accurate determination of population characteristics is required for predicting the ecological success of P. clarkii and its potential impacts on invaded ecosystems. In the current study, we addressed the question of trap efficiency by comparing population structure provided by eight trap devices (varying in number and position of entrances, mesh size, trap size and construction materials in three habitats (a pond, a reed bed and a grassland in a French marsh in spring 2010. Based on a large collection of P. clarkii (n = 2091, 272 and 213 respectively in the pond, reed bed and grassland habitats, we found that semi-cylindrical traps made from 5.5 mm mesh galvanized steel wire (SCG were the most efficient in terms of catch probability (96.7–100% compared to 15.7–82.8% depending on trap types and habitats and catch-per-unit effort (CPUE: 15.3, 6.0 and 5.1 crayfish·trap-1·24 h-1 compared to 0.2–4.4, 2.9 and 1.7 crayfish·trap-1·24 h-1 by the other types of fishing gear in the pond, reed bed and grassland respectively. The SCG trap was also the most effective for sampling all size classes, especially small individuals (carapace length \\hbox{$\\leqslant 30$} ⩽ 30 mm. Sex ratio was balanced in all cases. SCG could be considered as appropriate trapping gear to likely give more realistic information about P. clarkii population characteristics than many other trap types. Further investigation is needed to assess the catching effort required for ultimately proposing a standardised sampling method in a large range of habitats.

  9. A cell-surface superoxide dismutase is a binding protein for peroxinectin, a cell-adhesive peroxidase in crayfish.

    Science.gov (United States)

    Johansson, M W; Holmblad, T; Thörnqvist, P O; Cammarata, M; Parrinello, N; Söderhäll, K

    1999-03-01

    Peroxinectin, a cell-adhesive peroxidase (homologous to human myeloperoxidase), from the crayfish Pacifastacus leniusculus, was shown by immuno-fluorescence to bind to the surface of crayfish blood cells (haemocytes). In order to identify a cell surface receptor for peroxinectin, labelled peroxinectin was incubated with a blot of haemocyte membrane proteins. It was found to specifically bind two bands of 230 and 90 kDa; this binding was decreased in the presence of unlabelled peroxinectin. Purified 230/90 kDa complex also bound peroxinectin in the same assay. In addition, the 230 kDa band binds the crayfish beta-1,3-glucan-binding protein. The 230 kDa band could be reduced to 90 kDa, thus showing that the 230 kDa is a multimer of 90 kDa units. The peroxinectin-binding protein was cloned from a haemocyte cDNA library, using immuno-screening or polymerase chain reaction based on partial amino acid sequence of the purified protein. It has a signal sequence, a domain homologous to CuZn-containing superoxide dismutases, and a basic, proline-rich, C-terminal tail, but no membrane-spanning segment. In accordance, the 90 and 230 kDa bands had superoxide dismutase activity. Immuno-fluorescence of non-permeabilized haemocytes with affinity-purified antibodies confirmed that the crayfish CuZn-superoxide dismutase is localized at the cell surface; it could be released from the membrane with high salt. It was thus concluded that the peroxinectin-binding protein is an extracellular SOD (EC-SOD) and a peripheral membrane protein, presumably kept at the cell surface via ionic interaction with its C-terminal region. This interaction with a peroxidase seems to be a novel function for an SOD. The binding of the cell surface SOD to the cell-adhesive/opsonic peroxinectin may mediate, or regulate, cell adhesion and phagocytosis; it may also be important for efficient localized production of microbicidal substances.

  10. Determination of mercury by cold-vapor technique in several tissues of treated American red crayfish (Procambarus clarkii)

    Energy Technology Data Exchange (ETDEWEB)

    Del Ramo, J.; Pastor, A.; Diaz-Mayans, J.; Medina, J.; Torreblanca, A.

    1988-01-01

    Adult intermolt specimens of American red crayfish (Procambarus clarkii) collected from Lake Albufera (Valencia, Spain), were exposed to mercury during 96 h. The Hg-concentrations used were 50, 100, and 250 ..mu..g Hg/l as Cl/sub 2/Hg. The content of mercury in muscle, midgut gland, antennal glands and gills was investigated. Determinations of mercury were made by cold-vapor technique and AAS. The mercury levels in all examined tissues increased significantly with increasing Hg-concentration in the water.

  11. Predation of the alien American mink Mustela vison on native crayfish populations in middle-sized streams in central and western Bohemia

    Czech Academy of Sciences Publication Activity Database

    Fischer, D.; Pavluvčík, P.; Sedláček, František; Šálek, Martin

    2009-01-01

    Roč. 58, č. 1 (2009), s. 45-56 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z60870520 Keywords : mink diet * stone crayfish * prey selectivity * density-dependent predation * Czech Republic Subject RIV: EG - Zoology Impact factor: 0.357, year: 2009

  12. The burrows of Parastacus defossus (Decapoda: Parastacidae, a fossorial freshwater crayfish from southern Brazil

    Directory of Open Access Journals (Sweden)

    Clarissa K. Noro

    2010-06-01

    Full Text Available Parastacus defossus Faxon, 1898 is a fossorial crayfish species, which constructs its burrows in swampy areas in southeast Uruguay and in the state of Rio Grande do Sul, Brazil. The present field study was carried out in Lami, Porto Alegre, Rio Grande do Sul, Brazil, from May 2003 through August 2005. Environmental measurements (temperature, pH, dissolved oxygen, and water-table depth of the water in the galleries were made monthly. Burrow morphology was analyzed by means of resin and gypsum casts. The spatial distribution and changes in the number and shape of the surface openings over time were observed in a 100 m² area. To estimate the spatial distribution of the openings, the observed distribution was compared with the expected distribution predicted by the Poisson and Negative Binomial frequency-distribution models. The adult population density was estimated by direct observation of burrows and counts in the study area. Inside the burrows of P. defossus, the water temperature ranged between 16.6°C (autumn 2004 and 23°C (spring 2003. The water was hypoxic and slightly acidic, and the dissolved oxygen content was very low (mean 1.43 mg/l (18.2% saturation. The soil with burrows had higher percentages of coarse sand, fine sand, and silt. The spatial distribution of the openings showed a significant fit to the Negative Binomial distribution, indicating that the distribution of the openings is aggregated, as confirmed from the burrow morphology. The galleries are always formed by a central tunnel with multiple branchings that connect the underground water to the soil surface by one or more openings, which can be recognized by the chimneys. From knowledge of the burrow morphology, the population density was estimated to be about 120 individuals/100 m².

  13. Protection effect of GDNF and neurturin on photosensitized crayfish neurons and glial cells.

    Science.gov (United States)

    Uzdensky, Anatoly; Komandirov, Maxim; Fedorenko, Grigory; Lobanov, Andrej

    2013-03-01

    Neurons and glial cells can protect each other from stress and following death by mutual exchange with neurotrophins. In order to examine involvement of different neurotrophic factors in neuroglial interactions in a photosensitized crayfish stretch receptor, a simple model object consisting of only two sensory neurons enveloped by glial cells, we studied the influence of glial cell line-derived neurotrophic factor (GDNF), neurturin, and ciliary neurotrophic factor (CNTF) on its photodynamic injury. Photodynamic treatment, which causes strong oxidative stress, induced firing abolition and necrosis of neurons, necrosis, and apoptosis of glial cells. GDNF significantly reduced photoinduced neuronal necrosis and neurturin but not CNTF showed a similar tendency. Both of them significantly reduced necrosis and apoptosis of glial cells. At the ultrastructural level, neurons and glial cells treated with GDNF in the darkness contained large mitochondria with well-developed cristae, numerous ribosomes, polysomes, rough endoplasmic reticulum (ER), and dictyosomes. This indicated the high level of bioenergetic, biosynthetic, and transport processes. Photodynamic treatment caused swelling and vacuolization of mitochondria, dictyosomes, and ER. It also impaired formation of glial protrusions and double membrane vesicles that transfer glial material into the neuron. GDNF prevented photoinduced mitochondria swelling that disturbed the cellular bioenergetics and cytoplasm vacuolization associated with injury of intracellular organelles. It also preserved the structures involved in protein synthesis and transport: rough ER, dictyosomes, polysomes, microtubule bundles, submembrane cisterns, and double membrane vesicles. GDNF-mediated maintenance of metabolism and ultrastructure of photosensitized neurons and glial cells may be the basis of its neuro- and glia protective effects.

  14. Phylogeny and evolutionary patterns in the Dwarf crayfish subfamily (Decapoda: Cambarellinae.

    Directory of Open Access Journals (Sweden)

    Carlos Pedraza-Lara

    Full Text Available The Dwarf crayfish or Cambarellinae, is a morphologically singular subfamily of decapod crustaceans that contains only one genus, Cambarellus. Its intriguing distribution, along the river basins of the Gulf Coast of United States (Gulf Group and into Central México (Mexican Group, has until now lacked of satisfactory explanation. This study provides a comprehensive sampling of most of the extant species of Cambarellus and sheds light on its evolutionary history, systematics and biogeography. We tested the impact of Gulf Group versus Mexican Group geography on rates of cladogenesis using a maximum likelihood framework, testing different models of birth/extinction of lineages. We propose a comprehensive phylogenetic hypothesis for the subfamily based on mitochondrial and nuclear loci (3,833 bp using Bayesian and Maximum Likelihood methods. The phylogenetic structure found two phylogenetic groups associated to the two main geographic components (Gulf Group and Mexican Group and is partially consistent with the historical structure of river basins. The previous hypothesis, which divided the genus into three subgenera based on genitalia morphology was only partially supported (P = 0.047, resulting in a paraphyletic subgenus Pandicambarus. We found at least two cases in which phylogenetic structure failed to recover monophyly of recognized species while detecting several cases of cryptic diversity, corresponding to lineages not assigned to any described species. Cladogenetic patterns in the entire subfamily are better explained by an allopatric model of speciation. Diversification analyses showed similar cladogenesis patterns between both groups and did not significantly differ from the constant rate models. While cladogenesis in the Gulf Group is coincident in time with changes in the sea levels, in the Mexican Group, cladogenesis is congruent with the formation of the Trans-Mexican Volcanic Belt. Our results show how similar allopatric

  15. Calcium currents and conductances in the msucle membrane of the crayfish.

    Science.gov (United States)

    Hencek, M; Zachar, J

    1977-06-01

    1. Membrane currents in calcium type muscle membrane of the cray-fish Astacus fluviatilis were analysed by a method in which a membrane microarea was isolated by circulating sucrose rings contacting the fibre perpendicular to the fibre surface.2. The early calcium inward currents were separated from the total membrane currents by subtraction of the early and delayed potassium currents from the total membrane current.3. The isolated calcium currents show a time course characteristic for a transient change of calcium conductance. The presence of inactivation was further checked by the time course of the tail currents at the end of voltage clamp pulses of variable duration.4. The reversal potential of the early calcium currents determined from the current-voltage relations was +85 +/- 4.2 mV. The calcium potentials were used to express the calcium currents in the form of chord conductances.5. Calcium conductances (g(Ca)) as functions of time and voltage were found to be described quantitatively on the assumption that g(Ca) is determined by two variables (m and h), according to the equation g(Ca) = m(6)hg(Ca), where g(Ca) is a constant and m and h obey first order differential equations of the Hodgkin-Huxley type.6. The activation parameters of the g(Ca) were determined by fitting the solutions of the above equations to the experimental values of the g(Ca). This method was also used to check the inactivation parameters.7. The inactivation parameters of the g(Ca) were obtained from the inactivation curves, which were determined for several membrane potentials by variation of the duration of the conditioning step.8. The average calcium conductance constants were tabulated and compared with sodium conductance constants in excitable membranes.

  16. Assessment of neuroglial relationships under photodynamic treatment using fluorescent visualization of giant axons in crayfish ventral nerve cord

    Science.gov (United States)

    Duz, Eugeny; Kolosov, Mikhail S.

    2014-01-01

    There are lots of publications last time about important role of neuroglial interactions in normal physiology of nervous system. Some of them infer that neuroglial interactions may support survival of neuronal and glial cells. Study the mechanisms of neuroglial interactions needs convenient models which are simple nervous system. They could be easily isolated and studied while retain natural neuroglial relations. The purpose of present work was to estimate glia protective properties of giant axons in simple model - crayfish ventral nerve cord, upon photooxidative stress. To better visualize the axons shape and reveal the periaxonal glial cells, we were filling of the axons with fluorescent label by means of specially devised microinjector. It enabled us to reveal the glial cells which are in close proximity to the axons. Such glial cells was found to have increased survival in compare to more distant ones from the axons under oxidative stress. The obtained data indicate that the crayfish giant axons have glia protective properties, which molecular mechanisms have to be studied.

  17. Sperm traits negatively covary with size and asymmetry of a secondary sexual trait in a freshwater crayfish.

    Science.gov (United States)

    Galeotti, Paolo; Bernini, Guido; Locatello, Lisa; Sacchi, Roberto; Fasola, Mauro; Rubolini, Diego

    2012-01-01

    In species where females mate promiscuously, the reproductive success of males depends both on their ability to acquire mates (pre-copulatory sexual selection) and ability of their ejaculates to outcompete those of other males (post-copulatory sexual selection). Sperm competition theory predicts a negative relationship between investment in body traits favouring mate acquisition (secondary sexual characters, SSCs) and investment in ejaculate size or quality, due to the inherent costs of sperm production. In contrast, the phenotype-linked fertility hypothesis posits that male fertilizing efficiency is reliably reflected by the phenotypic expression of male SSCs, allowing females to obtain direct benefits by selecting more ornamented males as copulation partners. In this study, we investigated the relationships between male SSCs and size and quality (viability and longevity) of ejaculates allocated to females in mating trials of the freshwater crayfish Austropotamobius italicus. We showed that the relative size of male weapons, the chelae, was negatively related to ejaculate size, and that chelae asymmetry, resulting from regeneration of lost chelipeds, negatively covaried with sperm longevity. Moreover, males allocated more viable sperm to mates from their own rather than different stream of origin. Our findings thus suggest that, according to sperm competition theory, pre-copulatory sexual selection for large weapons used in male fighting may counteract post-copulatory sperm competition in this crayfish species, and that investment in cheliped regeneration may impair ejaculate quality.

  18. Sperm traits negatively covary with size and asymmetry of a secondary sexual trait in a freshwater crayfish.

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    Paolo Galeotti

    Full Text Available In species where females mate promiscuously, the reproductive success of males depends both on their ability to acquire mates (pre-copulatory sexual selection and ability of their ejaculates to outcompete those of other males (post-copulatory sexual selection. Sperm competition theory predicts a negative relationship between investment in body traits favouring mate acquisition (secondary sexual characters, SSCs and investment in ejaculate size or quality, due to the inherent costs of sperm production. In contrast, the phenotype-linked fertility hypothesis posits that male fertilizing efficiency is reliably reflected by the phenotypic expression of male SSCs, allowing females to obtain direct benefits by selecting more ornamented males as copulation partners. In this study, we investigated the relationships between male SSCs and size and quality (viability and longevity of ejaculates allocated to females in mating trials of the freshwater crayfish Austropotamobius italicus. We showed that the relative size of male weapons, the chelae, was negatively related to ejaculate size, and that chelae asymmetry, resulting from regeneration of lost chelipeds, negatively covaried with sperm longevity. Moreover, males allocated more viable sperm to mates from their own rather than different stream of origin. Our findings thus suggest that, according to sperm competition theory, pre-copulatory sexual selection for large weapons used in male fighting may counteract post-copulatory sperm competition in this crayfish species, and that investment in cheliped regeneration may impair ejaculate quality.

  19. Novel Insights into Antiviral Gene Regulation of Red Swamp Crayfish, Procambarus clarkii, Infected with White Spot Syndrome Virus

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    Shaokui Yi

    2017-11-01

    Full Text Available White spot syndrome virus (WSSV, one of the major pathogens of Procambarus clarkii, has caused severe disruption to the aquaculture industry of P. clarkii in China. To reveal the gene regulatory mechanisms underlying WSSV infection, a comparative transcriptome analysis was performed among WSSV-infected susceptible individuals (GS, viral resistant individuals (GR, and a non-infected control group (GC. A total of 61,349 unigenes were assembled from nine libraries. Subsequently, 515 and 1033 unigenes exhibited significant differential expression in sensitive and resistant crayfish individuals compared to the control group (GC. Many differentially expressed genes (e.g., C-type lectin 4, Peroxinectin, Prophenoloxidase, and Serine/threonine-protein kinase observed in GR and GS play critical roles in pathogen recognition and viral defense reactions after WSSV infection. Importantly, the glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulfate pathway was identified to play critical roles in defense to WSSV infection for resistant crayfish individuals by upregulating the chondroitin sulfate related genes for the synthesis of WSSV-sensitive, functional chondroitin sulfate chains containing E units. Numerous genes and the key pathways identified between resistant and susceptible P. clarkii individuals provide valuable insights regarding antiviral response mechanisms of decapoda species and may help to improve the selective breeding of P. clarkii WSSV-resistance.

  20. Appropriate Usage Level of Shrimp Waste Meal as Chitin Source for Feeding Young Crayfish (Astacus leptodactylus Esch. 1823

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    Seval Bahadır Koca*, Nalan Ozgur Yigit, Arife Dulluc, Gonca Erol1, Nihal Cılbız1 and Ramazan Kucukkara1

    2011-06-01

    Full Text Available This study was conducted to determine effects of shrimp waste meal as natural chitin source at different rates (0 (control, 10, 20, 30 and 40% on growth, feed conversion ratio (FCR, survival of young crayfish (1.61±0.04 g and 3.74±0.03 cm for 60 days. Fifteen glass aquariums (70x30x40 cm were used in the experiment and 20 individuals were stocked per aquarium (95/m2. The highest of final weight and weight gain were obtained in feed with 10% shrimp waste meal group (3.29±0.23 and 1.66±0.23 g, while the lowest of final weight and weight gain was obtained in fed with 40% shrimp waste meal group (2.75±0.35 and 1.18±0.37 g, respectively. However, non-significant differences were found between final weight, weight gain, specific growth rate, final total length, feed conversion ratio, survival percentage among groups at the end of experimental period. It was concluded that shrimp waste meal as natural chitin source can be used in young crayfish diets up to 40% without adverse effect influence on growth.

  1. Lunar-rhythmic molting in laboratory populations of the noble crayfish Astacus astacus (Crustacea, Astacidea: an experimental analysis.

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    Robert Franke

    Full Text Available Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea in the second year of age were kept in the laboratory for a twelve-month period under continuing "summer conditions" (LD 16:8, 19°C. Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at "new moons". Males showed a slightly higher degree of synchronization than females. A phase-shift of the artificial lunar cycle in relation to the natural cycle resulted in a corresponding shift of the molting cycle. This clearly demonstrates that changes in the nocturnal light regime provide the primary external information for the lunar-monthly molting rhythm. There is a first indication that lunar photic stimuli do not act directly but as a zeitgeber which entrains an endogenous molting rhythm to the lunar cycle. Moreover, the results of the long-term experiments suggest that the hibernal resting period of A. astacus in the field (no molts between October and April may also involve some endogenous programming. Continuing artificial summer conditions can delay but not completely suppress this resting period. The adaptive significance of the phenomena and how the findings may be applied to improve the management of crowded crayfish stocks are discussed.

  2. GENETIC DIFFERENTIATION BETWEEN NOBLE CRAYFISH, ASTACUS ASTACUS (L., POPULATIONS DETECTED BY MICROSATELLITE LENGTH VARIATION IN THE RDNA ITS1 REGION

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    EDSMAN L.

    2002-07-01

    Full Text Available The Internal Transcribed Spacer (ITS region of the nuclear ribosomal repeat was investigated in the search for a suitable genetic marker for population studies of the noble crayfish Astacus astacus (L.. DNA sequencing revealed the presence of two microsatellite insertions in ITS1. By designing highly specific PCR primers, adjacent to one of the insertions, we were able to use fragment analysis to explore the variation of the insertion in 642 specimens from 17 populations of crayfish from Sweden and former Yugoslavia. A new statistical test, the Population Divergence Test, was developed to assess statistical significance of divergence between populations. This test does not assume Mendelian inheritance. Our results demonstrate that different populations often produce characteristic fragment patterns, and that most, but not all, populations are genetically distinct, with high significance. The populations that cannot be significantly differentiated are situated in close geographic proximity to each other and belong to the same main river system, probably reflecting that these populations have had recent contact and that gene flow has occurred.

  3. Protein modification in the post-mating spermatophore of the signal crayfish Pacifastacus leniusculus: insight into the tyrosine phosphorylation in a non-motile spermatozoon.

    Science.gov (United States)

    Niksirat, Hamid; Vancová, Marie; Andersson, Liselotte; James, Peter; Kouba, Antonín; Kozák, Pavel

    2016-09-01

    After mating, spermatophores of signal crayfish are stored on the body of the female for a period before fertilization. This study compared the post-mating protein profile and pattern of protein tyrosine phosphorylation of the signal crayfish spermatophore to that of the freshly ejaculated spermatophore and found substantial differences. Two major bands of tyrosine-phosphorylated proteins of molecular weights 10 and 50kDa were observed in the freshly ejaculated spermatophore of the signal crayfish. While the tyrosine-phosphorylated protein band with molecular weight 10kDa was formed by protein(s) of similar pH, the band with molecular weight of 50kDa consisted of proteins of varying pH. In the post-mating spermatophore, the band with molecular weight of 50kDa was not detected, and an increase in the level of protein tyrosine phosphorylation was observed in the 10kDa band. The microtubular radial arms of the spermatozoon showed a positive reaction to an anti-tyrosine antibody conjugated with gold particles in both the freshly ejaculated and post-mating spermatophores. In conclusion, the male gamete of the signal crayfish undergoes molecular modification during post-mating storage on the body of the female including changes in the level of protein expression and protein tyrosine phosphorylation. Structural similarity of the radial arms in the crayfish immotile spermatozoon with flagellum, which is the main site of protein tyrosine phosphorylation in the mammalian motile spermatozoa, raises questions regarding evolution and function of such organelles across the animal kingdom that must be addressed in the future studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Tissue distribution and correlation profiles of heavy-metal accumulation in the freshwater crayfish Astacus leptodactylus.

    Science.gov (United States)

    Tunca, Evren; Ucuncu, Esra; Ozkan, Alper Devrim; Ulger, Zeynep Ergul; Tekinay, Turgay

    2013-05-01

    The present work details the analysis of heavy-metal and metalloid concentrations in exoskeleton, gill, hepatopancreas, and abdominal muscle tissues of 60 crayfish (Astacus leptodactylus) specimens collected from Lake Hirfanlı, a dam lake located in Kırşehir (Turkey) with a low metal-contamination profile. Concentrations of 11 metals (aluminum [Al], chromium [Cd], manganese [Mn], cobalt [Co], nickel [Ni], copper [Cu], molybdenum [Mo], silver [Ag], cadmium [Cd], mercury [Hg], and lead [Pb]) and a metalloid (arsenic [As]) were measured by inductively coupled plasma-mass spectrometry, and the relative frequencies of the most abundant isotopes of Cr, Cu, Ag, Cd, Hg, and Pb were evaluated. Three correlation trends were evaluated between the following: (1) different elements in the each individual tissue, (2) individual elements in different tissues, and (3) different elements in different tissues. In addition, correlation rates of growth parameters (weight, cephalothorax length, and total length) with heavy-metal and metalloid concentrations in each tissue were investigated. Our results suggest that substantial differences in metal and metalloid-accumulation levels exist between male and female specimens, with stronger correlations between the heavy-metal concentrations observed in the male cohort. It is notable that correlation trends of Co, Cu, (52)As, Cr, and Ni in exoskeleton of the male specimens display strong similarities. Likewise, a very strong correlation is present in Ni-Cd and Ni-Pb accumulations in abdominal muscle of the male specimens; a similar trend is present between Cd and Pb concentrations in the same tissue of female specimens. For correlation rates of different heavy metals and metalloid in different tissues, the strongest positive association observed was between (63)Cu in gill and As in hepatopancreas, whereas the strongest negative correlation was between accumulated Ni in abdominal muscle and As in exoskeleton. Strong correlations between

  5. Relative abundance and distribution of fishes and crayfish at Ash Meadows National Wildlife Refuge, Nye County, Nevada, 2007-08

    Science.gov (United States)

    Scoppettone, G. Gary; Rissler, Peter; Johnson, Danielle; Hereford, Mark

    2011-01-01

    This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red

  6. The effect of sodium ions on the light-induced 86Rb release from the isolated crayfish retina

    International Nuclear Information System (INIS)

    Hartung, K.; Stieve, H.

    1980-01-01

    The effect of low external Na + concentrations on the light-induced K + release from crayfish photoreceptor cells was tested by labelling intracellular K + with the isotope 86 Rb. The amount of isotope released per light, stimulus is roughly proportional to the external Na + concentration if the osmolarity is kept constant by replacing Na + with Tris, choline or sucrose. When sucrose is used to replace the depleted Na + the light-induced K + release is a linear function of the external Na + concentration and is reduced by approx. 95% at an external Na + concentration of 5 mmol/l. For choline and Tris substitutions the relationships are less clear but at Na + concentrations + release is smaller in a Tris solution and larger in a choline solution. It is suggested that the light-induced K + release is due mainly to an activation of voltage sensitive K + channels. (orig.)

  7. What vaccination studies tell us about immunological memory within the innate immune system of cultured shrimp and crayfish.

    Science.gov (United States)

    Chang, Yu-Hsuan; Kumar, Ramya; Ng, Tze Hann; Wang, Han-Ching

    2018-03-01

    The possibility of immunological memory in invertebrates is a topic that has recently attracted a lot of attention. Today, even vertebrates are known to exhibit innate immune responses that show memory-like properties, and since these responses are triggered by cells that are involved in the innate immune system, it seems that immune specificity and immune memory do not necessarily require the presence of B cells and T cells after all. This kind of immune response has been called "immune priming" or "trained immunity". In this report, we review recent observations and our current understanding of immunological memory within the innate immune system in cultured shrimp and crayfish after vaccination with live vaccine, killed vaccine and subunit vaccines. We also discuss the possible mechanisms involved in this immune response. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Toxicity of some ricefield pesticides to the crayfish P. clarkii, under laboratory and field conditions in Lake Albufera (Spain).

    Science.gov (United States)

    Andreu-Moliner, E S; Almar, M M; Legarra, I; Núñez, A

    1986-12-01

    Static toxicities in mature crayfish (Procambarus clarkii) were determined, for eight insecticides, two herbicides and one fungicide which were frequently used in rice cultivation at Lake Albufera in Valencia (Spain). Three concentrations of each product were used: a) The concentration that was recommended by the dealer (in mg/L of active ingredient): Carbofuran 0.40, Carbaryl 0.80, Malathion 0.80, Trichlorfon 0.40, Endosulfan 0.56, Lindane 0.56, Fenitrothion 0.40, Cyfloxylate 0.02, Molinate-Thiobencarb 1.50, Copper Sulfate 0.42, b) Half of the recommended concentration. c) Double of the recommended concentration. In all three of the concentrations tested, only Fenitrothion and Cyfloxylate caused a considerable mortality. The other ones do not actually produce any important effects on P. clarkii in our conditions. Nevertheless, insecticides are more toxic than herbicides or fungicides, as the latter show a rather low toxicity.

  9. Two genetic variants of the crustacean hyperglycemic hormone (CHH) from the Australian crayfish, Cherax destructor: detection of chiral isoforms due to posttranslational modification.

    Science.gov (United States)

    Bulau, Patrick; Meisen, Iris; Reichwein-Roderburg, Barbara; Peter-Katalinić, Jasna; Keller, Rainer

    2003-12-01

    From sinus glands of the Australian crayfish Cherax destructor, two genetic variants of the crustacean hyperglycemic hormone (CHH) were isolated by HPLC and fully characterized by mass spectrometry and Edman sequencing. Both CHH A (8350.38 Da) and CHH B (8370.34 Da) consist of 72 amino acid residues, with pyroGlu as N-terminus and an amidated (Val-NH2) C-terminus. They differ in 14 residues (81% identity). Both sequences are significantly different from those of the hitherto known three CHHs of Astacoidea species (Northern hemisphere crayfish), which among themselves are extremely conserved. This may reflect the long, separate evolution of the Astacoidea lineage and the Parastacoidea (Southern hemisphere crayfish) lineage, to which Cherax belongs. CHH A and CHH B genes are expressed at comparable levels, as indicated by the similar amounts of mature peptides in the sinus gland. In addition to each of the major peptides, which share the identical N-terminal tripeptide pyroGlu-Val-L-Phe, one chiral isoform containing pyroGlu-Val-D-Phe was identified. Compared to the main peptides, the amounts of the D-isoforms are lower, but significant, amounting to 30-40% of L-isoforms. These results demonstrate that two genes can give rise to a total of four different peptides in the secretory terminals of the sinus gland. All peptides gave a highly significant hyperglycemic in vivo response in C. destructor.

  10. Exposure of the eggs to 17{alpha}-methyl testosterone reduced hatching success and growth and elicited teratogenic effects in postembryonic life stages of crayfish

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, Guenter [Zoological Institute and Museum, University of Greifswald, Johann-Sebastian-Bach-Strasse 11/12, D-17487 Greifswald (Germany)], E-mail: gunter.vogt@web.de

    2007-12-30

    Testosterone is regularly found in the tissues of decapod crustaceans. Although this vertebrate-type sex hormone is not the principal factor of sex differentiation in crustaceans, it was shown to be capable of acting on the reproductive organs of shrimps and crabs. In the present study I have exposed developing eggs and stage 5 juveniles of the parthenogenetic all female marbled crayfish to 17{alpha}-methyl testosterone in order to test whether in freshwater crayfish sex can be changed from female to male by this androgen. MT did not elicit sex change, neither when administered during embryonic development nor during juvenile stage 5, the main period of proliferation of the oocytes. However, exposure to 100 {mu}g/L MT from 64% to 84% embryonic development resulted in prolonged embryonic development, reduced hatching success, reduced growth of the juveniles, and severe malformations of the appendages in the juveniles. The marbled crayfish is recommended to be considered for toxicity tests due to its easy culture in the laboratory and its genotypical uniformity.

  11. Subcellular localization of calcium deposits in the noble crayfish Astacus astacus spermatophore: Implications for post-mating spermatophore hardening and spermatozoon maturation.

    Science.gov (United States)

    Niksirat, Hamid; Kouba, Antonín

    2016-04-01

    The freshly ejaculated spermatophore of crayfish undergoes a hardening process during post-mating storage on the body surface of female. The ultrastructural distribution of calcium deposits were studied and compared in freshly ejaculated and post-mating noble crayfish spermatophores, using the oxalate-pyroantimonate technique, to determine possible roles of calcium in post-mating spermatophore hardening and spermatozoon maturation. Small particles of sparsely distributed calcium deposits were visible in the wall of freshly ejaculated spermatophore. Also, large amount of calcium deposits were visible in the membranes of the freshly ejaculated spermatozoon. Five minutes post-ejaculation, granules in the spermatophore wall appeared as porous formations with numerous electron lucent spaces. Calcium deposits were visible within the spaces and scattered in the spermatophore wall matrix, where smaller calcium deposits combined to form globular calcium deposits. Large numbers of the globular calcium deposits were visible in the wall of the post-mating spermatophore. Smaller calcium deposits were detected in the central area of post-mating spermatophore, which contains the sperm mass, and in the extracellular matrix and capsule. While the density of calcium deposits decreased in the post-mating spermatozoon membranes, numerous small calcium deposits appeared in the subacrosomal zone and nucleus. Substantial changes in calcium deposit distribution in the crayfish spermatophore during post-mating storage on the body of female may be involved in the processes of the spermatophore hardening and spermatozoon maturation. © 2016 Wiley Periodicals, Inc.

  12. To signal or not to signal? Chemical communication by urine-borne signals mirrors sexual conflict in crayfish

    Directory of Open Access Journals (Sweden)

    Breithaupt Thomas

    2010-03-01

    Full Text Available Abstract Background Sexual selection theory predicts that females, being the limiting sex, invest less in courtship signals than males. However, when chemical signals are involved it is often the female that initiates mating by producing stimuli that inform about sex and/or receptivity. This apparent contradiction has been discussed in the literature as 'the female pheromone fallacy'. Because the release of chemical stimuli may not have evolved to elicit the male's courtship response, whether these female stimuli represent signals remains an open question. Using techniques to visualise and block release of urine, we studied the role of urine signals during fighting and mating interactions of crayfish (Pacifastacus leniusculus. Test individuals were blindfolded to exclude visual disturbance from dye release and artificial urine introduction. Results Staged female-male pairings during the reproductive season often resulted in male mating attempts. Blocking female urine release in such pairings prevented any male courtship behaviour. Artificial introduction of female urine re-established male mating attempts. Urine visualisation showed that female urine release coincides with aggressive behaviours but not with female submissive behaviour in reproductive interactions as well as in intersexual and intrasexual fights. In reproductive interactions, females predominately released urine during precopulatory aggression; males subsequently released significantly less urine during mating than in fights. Conclusions Urine-blocking experiments demonstrate that female urine contains sex-specific components that elicit male mating behaviour. The coincidence of chemical signalling and aggressive behaviour in both females and males suggests that urine release has evolved as an aggressive signal in both sexes of crayfish. By limiting urine release to aggressive behaviours in reproductive interactions females challenge their potential mating partners at the same

  13. The assessment of the habitat and water quality requirements of the stone crayfish (Austropotamobius torrentium and noble crayfish (Astacus astacus species in the rivers from the Anina Mountains (SW Romania

    Directory of Open Access Journals (Sweden)

    Pârvulescu L.

    2011-02-01

    Full Text Available The species Austropotamobius torrentium and Astacus astacus are two species known in the EU directives to require deeper understanding of their autecologic requirements before any sustainable conservation effort could be successfully applied. Therefore, the paper aims to analyze the occurrence of these two species of crayfish in the Anina Mountains (Romania in relation to several physical-chemical indicators measured on site. The results suggest that the anthropogenic impacts registered in some of the sampling sites (e.g. organic pollution and river bed modification might have triggered the disappearance of both species from the areas of the water sheds situated downstream villages and towns, deforestation sites and sewage treatment plants. The analysis suggest that both species might have similar ecologic requirements, with a BMWP score of 8 (out of a possible 10, therefore good indicators of pristine aquatic environments and with a possible toleration to pollution but only up to a moderate level. Nevertheless, the lack of cohabitation of the populations of both species at a local scale was discussed along with two possible explaining hypotheses: behavioral exclusion or different times and/or modalities of dispersal history.

  14. Fatty acids and astaxanthin composition of two edible native Mexican crayfish Cambarellus (C.) montezumae and Procambarus (M.) bouvieri

    International Nuclear Information System (INIS)

    Coral-Hinostroza, G.; Diaz-Martinez, M.; Huberman, A.; Silencio-Barrita, J.L.

    2016-01-01

    The content and composition of the fatty acids (F As) and astaxanthin (AST) in the edible forms of crayfish: the whole animal of Cambarellus (C.) montezumae, and the tail meat (TM) of Procambarus (M.) bouvieri were determined by GC and HPLC. The exoskeleton (EXK) of P. (M.) bouvieri was also studied. Unsaturated FAs, and mostly oleic acid (C18:1 n-9), were predominant in both edible forms. The contents of the polyunsaturated eicosapentaenoic (C20:5 n-3, EPA), arachidonic (C20:4 n-6, ARA) and docosahexaenoic acid (C22:6 n-3, DHA), were higher in the TM of P. (M.) bouvieri than in the complete C. (C.) montezumae (p<0.05). Total carotenoids ranged between 2.31 ± 0.33 μg·g−1 and 66.3 ± 3.91 μg·g−1, and were composed mainly of AST (>79.50%). AST esters were enriched with saturated FAs in C. (C.) montezumae and with PUFAs in EXK of P. (M.) bouvieri. We conclude that both C. (C.) montezumae and the TM of P. (M.) bouvieri are traditional foods rich in n-3 PUFAs and C. (C.) montezumae in AST. The EXK of P. (M.) bouvieri is a rich potential source of AST, n-3 PUFAs, and the combination AST-DHA. [es

  15. Inferring Invasion History of Red Swamp Crayfish (Procambarus clarkii in China from Mitochondrial Control Region and Nuclear Intron Sequences

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    Yanhe Li

    2015-06-01

    Full Text Available Identifying the dispersal pathways of an invasive species is useful for adopting the appropriate strategies to prevent and control its spread. However, these processes are exceedingly complex. So, it is necessary to apply new technology and collect representative samples for analysis. This study used Approximate Bayesian Computation (ABC in combination with traditional genetic tools to examine extensive sample data and historical records to infer the invasion history of the red swamp crayfish, Procambarus clarkii, in China. The sequences of the mitochondrial control region and the proPOx intron in the nuclear genome of samples from 37 sites (35 in China and one each in Japan and the USA were analyzed. The results of combined scenarios testing and historical records revealed a much more complex invasion history in China than previously believed. P. clarkii was most likely originally introduced into China from Japan from an unsampled source, and the species then expanded its range primarily into the middle and lower reaches and, to a lesser extent, into the upper reaches of the Changjiang River in China. No transfer was observed from the upper reaches to the middle and lower reaches of the Changjiang River. Human-mediated jump dispersal was an important dispersal pathway for P. clarkii. The results provide a better understanding of the evolutionary scenarios involved in the rapid invasion of P. clarkii in China.

  16. Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons

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    Italo Salgado-Leu

    2015-11-01

    Full Text Available In cultivated aquatic organisms nutritional requirements are critical, not only for their impact on production techniques, but also, for their high incidence on production costs. There is limited knowledge on some species such as the southern Chilean freshwater crayfish, Samastacus spinifrons. In order to generate practical knowledge, a study was carried out to determine protein and carbohydrate content requirements. These factors were evaluated upon their effects on growth and survival of juveniles. For this purpose, individual weight, biomass gain, survival, and feed conversion parameters were measured. The assay was carried out in 42 days, it was conducted in a flow through system, using 21 plastic tanks of 10.6 L capacity. Each tank was seeded with 20 juveniles weighing 50 mg average each. A 3×2 factorial design was proposed with three protein contents (20, 30, 40% and two carbohydrate contents (low: from 16.3 to 23.5% and high: from 34.6 to 35.8%. Six treatments and three replicates were performed. Individuals were fed on apparent satiation once a day. The diets formulated with 30% of protein and the two carbohydrate contents resulted in higher biomass increases, food conversion efficiencies over 26%, and specific growth rate of 0.78%, all displaying significant differences. Survival showed highly significant differences; in all diets were superior to 60%, however the diets with 30% of protein surpassed 90%.

  17. Environmental covariates associated with Cambarus veteranus Faxon, 1914 (Decapoda: Cambaridae), an imperiled Appalachian crayfish endemic to West Virginia, USA

    Science.gov (United States)

    Loughman, Zachary J.; Welsh, Stuart A.; Sadecky, Nicole M.; Dillard, Zachary W.; Scott, R. Katie

    2016-01-01

    Cambarus veteranusFaxon, 1914, a narrow endemic crayfish native to the Upper Guyandotte River Basin (UGB) in West Virginia, USA, was petitioned in 2014 by the United States Fish and Wildlife Service to be listed as endangered, but a status survey was recommended to determine if listing was warranted. During May and June 2015, surveys were undertaken across the UGB to determine the current distribution of the species. A total of 71 sites were sampled, including all streams where the species was previously recorded, as well as semi-randomly selected streams, with $$1-9\\;125\\;{\\rm{m}}$$ long sites sampled per wadeable stream. Physiochemical and physical habitat data (based on the Qualitative Habitat Evaluation Index, QHEI) were obtained at each site to determine abiotic factors that were associated with the presence of C. veteranus. Site detection or non-detection of C. veteranus and associated site covariates were modeled using logistic regression to determine covariates associated with the presence of the species. Cambarus veteranus was present in both the Pinnacle Creek and Clear Fork/Laurel Fork watersheds at 10 sites, but it was not observed in the remaining 61 sites. An additive effects model with conductivity and QHEI was selected as the best approximating model. Cambarusveteranus was associated with lower than average UGB conductivity $$(379\\;\\mu {\\rm{S}})$$ and high $$( \\gt 80)$$ QHEI score. All sites where C. veteranus was not detected had higher conductivity and/or lower QHEI scores.

  18. Esterases as pesticide biomarkers in crayfish (Procambarus clarkii, Crustacea): tissue distribution, sensitivity to model compounds and recovery from inactivation.

    Science.gov (United States)

    Vioque-Fernández, A; de Almeida, E Alves; López-Barea, J

    2007-04-01

    The specific activities of acetyl- and butyrylcholinesterase and carboxylesterase were assayed in the digestive gland and in nervous and muscle tissues of the crayfish Procambarus clarkii. Since acetylcholinesterase prevails in nervous tissue and carboxylesterase in digestive gland, they are proposed as biomarkers. Muscle had negligible activities of all esterases, and all tissues had a low butyrylcholinesterase activity. Esterases were mostly cytosolic in digestive gland and muscle, but membrane-bound in nervous tissue; use of Triton X-100 is not recommended due to its widely diverging effects in esterase assays. Phenylmethylsulphonylfluoride inhibited acetyl- and butyrylcholinesterase in extracts from all tissues, and in digestive gland only carboxylesterase. In digestive gland, tetra[monoisopropyl]-pyrophosphorotetramide inhibited all esterases with different sensitivities, while in muscle and nervous tissue it only partially inhibited all esterases. Carbamates inhibited 100-fold more strongly than organophosphates acetyl- and butyrylcholinesterase activities. Carboxylesterase was inhibited by carbaryl and chlorpyrifos, but not by eserine and malathion. In vitro conditions to evaluate recovery from inactivation of esterases by model pesticides were established for acetylcholinesterase and carboxylesterase. The new reactivation protocol could be useful as a biomarker of pesticide exposure to differentiate between dilution-reversible inhibitions, indicating carbamate exposure, from dilution-irreversible effect, attributed to organophosphate exposure.

  19. The involvement of NF-κB in PDT-induced death of crayfish glial and nerve cells

    Science.gov (United States)

    Berezhnaya, E. V.; Neginskaya, M. A.; Kovaleva, V. D.; Rudkovskii, M. V.; Uzdensky, A. B.

    2015-03-01

    Photodynamic therapy (PDT) is used for selective destruction of cells, in particular, for treatment of brain tumors. However, photodynamic treatment damages not only tumor cells, but also healthy neurons and glial cells. To study the possible role of NF-κB in photodynamic injury of neurons and glial cells, we investigated the combined effect of photodynamic treatment and NF-κB modulators: activator betulinic acid, or inhibitors parthenolide and CAPE on an isolated crayfish stretch receptor consisting of a single neuron surrounded by glial cells. A laser diode (670 nm, 0.4 W/cm2) was used as a light source. The inhibition of NF-κB during PDT increased the duration of neuron firing and glial necrosis and decreased neuron necrosis and glial apoptosis. The activation of NF-κB during PDT increased neuron necrosis and glial apoptosis and decreased glial necrosis. The difference between the effects of NF-κB modulators on photosensitized neurons and glial cells indicates the difference in NF-κB-mediated signaling pathways in these cell types. Thus, NF-κB is involved in PDT-induced shortening of neuron firing, neuronal and glial necrosis, and apoptosis of glial cells.

  20. BIOLOGICAL WATER QUALITY ASSESSMENT OF THE WHITECLAWED CRAYFISH HABITAT BASED ON MACROINVERTEBRATE COMMUNITIES: USEFULNESS FOR ITS CONSERVATION

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    GRANDJEAN F.

    2003-04-01

    Full Text Available A survey of the macroinvertebrates of three brooks harbouring the white-clawed crayfish was conducted in Haute-Vienne department (France. Its aim was to increase our understanding of these ecosystems to help the conservation of A. pallipes. These brooks run through pastoral areas with well-developed riparian vegetation, which offers an important shade. Water temperature, dissolved oxygen concentration, pH, and conductivity fell within the ranges found for this species. A total of 34, 31, 29 taxa and 1 502, 1 364, 2 707 individuals of macrobenthos were collected in Holme, Besque and Bellecombe streams, respectively. Results showed good to very good water quality with IBGN scores ranging from 15 (Bellecombe to 17 (Holme and Besque, reflecting a limited impact of the anthropogenic disturbances. Taxa diversity were high for Holme and Besque with Shannon index around 3.2, translating a great heterogeneity of habitat and an equilibrated faunal community. Bellecombe showed a limited diversity with Shannon index of 1.42, resulting from the presence of numberous Chironomidae. This brook suffers probably weak organic pollution which could be related to the low water flow observed during the sampling. The similarity test according to Jaccard index showed high percentage of common taxa among ETP (Ephemeroptera-Trichoptera-Plecoptera between all sites. The high similarity of benthic macroinvertebrate communities could be an useful criteria to identify brooks for restocking purpose.

  1. Post-mating morphological changes in the spermatozoon and spermatophore wall of the crayfish Astacus leptodactylus: insight into a non-motile spermatozoon.

    Science.gov (United States)

    Niksirat, Hamid; Kouba, Antonín; Kozák, Pavel

    2014-10-01

    Morphology of the crayfish spermatozoon and of the spermatophore wall during three stages of final maturation including freshly ejaculated, post-mating, and after spermatozoa release was studied and compared. The crayfish spermatophore consists of a sperm mass enveloped by a three layered spermatophore wall. After mating, the thickness of the outer layer of the spermatophore is increased. The matrix in the middle layer of the spermatophore becomes reticulated, and granules inside this layer release their contents. Fibers in the inner layer degrade to small particles. The spermatozoon capsule swells and the space between the capsule and the spermatozoon appears. The area of the plasma membrane is increased by wrinkling of the surface and alteration from a single to a multilayered structure at the anterior part of the acrosome. The density of the subacrosome zone increases in the vicinity of the main body of the acrosome. With the onset of fertilization, the layers of the spermatophore are dissolved by female glair gland secretions. The spermatozoon extracellular capsule, plasma membrane, and membranous lamellae are eliminated, and bundles of filaments are released from anterior part of the acrosome. The subacrosome zone loses electron density and retracts. The electron-dense material of the innermost layer of the acrosome is discharged and, together with acrosome filaments, forms a filament/droplet structure at the anterior part of the spermatozoon. The most important change is observed in the subacrosome zone, which may play a key role in the fertilization. Also, morphological changes of the spermatozoon that occur after release from the capsule, especially formation of the filament/droplet structure, may contribute to the mechanism of egg-spermatozoon binding in the crayfish, representative of animals with non-motile spermatozoa. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Proteomic analysis of the crayfish gastrolith chitinous extracellular matrix reveals putative protein complexes and a central role for GAP 65.

    Science.gov (United States)

    Glazer, Lilah; Roth, Ziv; Weil, Simy; Aflalo, Eliahu D; Khalaila, Isam; Sagi, Amir

    2015-10-14

    Chitin is a major component of arthropod cuticles, where it forms a three-dimensional network that constitutes the scaffold upon which cuticles form. The chitin fibers that form this network are closely associated with specific structural proteins, while the cuticular matrix contains many additional structural, enzymatic and other proteins. We study the crayfish gastrolith as a simple model for the assembly of calcified cuticular structures, with particular focus on the proteins involved in this process. The present study integrates a gastrolith-forming epithelium transcriptomic library with data from mass spectrometry analysis of proteins extracted from the gastrolith matrix to obtain a near-complete picture of gastrolith protein content. Using native protein separation we identified 24 matrix proteins, of which 14 are novel. Further analysis led to discovery of three putative protein complexes, all containing GAP 65 the most abundant gastrolith structural protein. Using immunological methods we further studied the role of GAP 65 in the gastrolith matrix and forming epithelium, as well as in the newly identified protein complexes. We propose that gastrolith matrix construction is a sequential process in which protein complexes are dynamically assembled and disassembled around GAP 65, thus changing their functional properties to perform each step in the construction process. The scientific interest on which this study is based arises from three main features of gastroliths: (1) Gastroliths possess partial analogy to cuticles both in structural and molecular properties, and may be regarded, with the appropriate reservations (see Introduction), as simple models for cuticle assembly. At the same time, gastroliths are terminally assembled during a well-defined period, which can be controlled in the laboratory, making them significantly easier to study than cuticles. (2) Gastroliths, like the crayfish exoskeleton, contain stable amorphous calcium carbonate (ACC) rather

  3. A sexual shift induced by silencing of a single insulin-like gene in crayfish: ovarian upregulation and testicular degeneration.

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    Ohad Rosen

    2010-12-01

    Full Text Available In sequential hermaphrodites, intersexuality occurs naturally, usually as a transition state during sexual re-differentiation processes. In crustaceans, male sexual differentiation is controlled by the male-specific androgenic gland (AG. An AG-specific insulin-like gene, previously identified in the red-claw crayfish Cherax quadricarinatus (designated Cq-IAG, was found in this study to be the prominent transcript in an AG cDNA subtractive library. In C. quadricarinatus, sexual plasticity is exhibited by intersex individuals in the form of an active male reproductive system and male secondary sex characters, along with a constantly arrested ovary. This intersexuality was exploited to follow changes caused by single gene silencing, accomplished via dsRNA injection. Cq-IAG silencing induced dramatic sex-related alterations, including male feature feminization, a reduction in sperm production, extensive testicular degeneration, expression of the vitellogenin gene, and accumulation of yolk proteins in the developing oocytes. Upon silencing of the gene, AG cells hypertrophied, possibly to compensate for low hormone levels, as reflected in the poor production of the insulin-like hormone (and revealed by immunohistochemistry. These results demonstrate both the functionality of Cq-IAG as an androgenic hormone-encoding gene and the dependence of male gonad viability on the Cq-IAG product. This study is the first to provide evidence that silencing an insulin-like gene in intersex C. quadricarinatus feminizes male-related phenotypes. These findings, moreover, contribute to the understanding of the regulation of sexual shifts, whether naturally occurring in sequential hermaphrodites or abnormally induced by endocrine disruptors found in the environment, and offer insight into an unusual gender-related link to the evolution of insulins.

  4. Protection of the Crayfish Mechanoreceptor Neuron and Glial Cells from Photooxidative Injury by Modulators of Diverse Signal Transduction Pathways.

    Science.gov (United States)

    Uzdensky, Anatoly; Berezhnaya, Elena; Khaitin, Andrej; Kovaleva, Vera; Komandirov, Maxim; Neginskaya, Maria; Rudkovskii, Mikhail; Sharifulina, Svetlana

    2015-10-01

    Oxidative stress is the reason of diverse neuropathological processes. Photodynamic therapy (PDT), an effective inducer of oxidative stress, is used for cancer treatment, including brain tumors. We studied the role of various signaling pathways in photodynamic injury and protection of single neurons and satellite glial cells in the isolated crayfish mechanoreceptor. It was photosensitized with alumophthalocyanine Photosens in the presence of inhibitors or activators of various signaling proteins. PDT eliminated neuronal activity and killed neurons and glial cells. Inhibitory analysis showed the involvement of protein kinases Akt, glycogen synthase kinase-3β (GSK-3β), mammalian target of rapamycin (mTOR), mitogen-activated protein kinase kinases 1 and 2 (MEK1/2), calmodulin, calmodulin-dependent kinase II (CaMKII), adenylate cyclase, and nuclear factor NF-κB in PDT-induced necrosis of neurons. Nitric oxide (NO) and glial cell-derived neurotrophic factor (GDNF) reduced neuronal necrosis. In glial cells, protein kinases Akt, calmodulin, and CaMKII; protein kinases C and G, adenylate cyclase, and p38; and nuclear transcription factor NF-κB also mediated PDT-induced necrosis. In contrast, NO and neurotrophic factors nerve growth factor (NGF) and GDNF demonstrated anti-necrotic activity. Phospholipase Cγ, protein kinase C, GSK-3β, mTOR, NF-κB, mitochondrial permeability transition pores, and NO synthase mediated PDT-induced apoptosis of glial cells, whereas protein kinase A, tyrosine phosphatases, and neurotrophic factors NGF, GDNF, and neurturin were involved in protecting glial cells from photoinduced apoptosis. Signaling pathways that control cell survival and death differed in neurons and glia. Inhibitors or activators of some signaling pathways may be used as potential protectors of neurons and glia from photooxidative stress and following death.

  5. Feasibility, density and growth of culture of freshwater crayfish (Decapoda: Cherax Quadricarinatus in Sinaloa, México

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    Juan Francisco Arzola González

    2012-09-01

    Full Text Available Feasibility, density and growth of culture of freshwater crayfish (Cherax quadricarinatus in Sinaloa were analyzed between September, 2005 and January, 2006. The densities were 7 (reservoir 1 and 16 (reservoir 2 org/m-2. Applied a method not parametrico (Kruskal-Wallis, the variables of response were density, weight and sex, the experimental unit the reservoirs. Samplings were weekly and 40 lobsters were captured in tubes of PVC. Total and cefalotorácica length ((LT y LC in mm and total weight (PT in g of the organisms were recorded, the biometric correlations were realized and von Bertalanffy estimated the growth for the model of von Bertallanfy. The major average was obtained in 41.2 g to a density of 7 org/m, though her k (growth rate coincided with the reservoirs with 0.30, in addition, the lobsters they presented a growth of isometric type. From the first year, usefulness of $3,419,165.00 obtained, that represented 26.8 % of the total of income, keeping a growth like that supported until the fifth year (2011. The financial evaluation determined that the investment is profitable economically, his analysis of VAN was $9,060,554.00, and in agreement to the financial indicators, this value was ideal for the accomplishment of the project. As indicator of the profitability, the TIR resulted in 66 %, being major that the minimal acceptable rate of performance and concluding the profitability of the culture in 59 %. Likewise, Sinaloa's condition, for his geographical location and the results ofthe growth, the heights, the performance of the lobster and of the financial analysis of the culture, indicated to C. quadricarinatusas an alternative of development in the region, being the lobster of interest in acuiculture of new species in tropical areas, thoughin Sinaloa the investigations are practically void with ends of commercial production.

  6. Effects of both ecdysone and the acclimation to low temperature, on growth and metabolic rate of juvenile freshwater crayfish Cherax quadricarinatus (Decapoda, Parastacidae

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    Anouk Chaulet

    2013-06-01

    Full Text Available Growth, metabolic rate, and energy reserves of Cherax quadricarinatus (von Martens, 1868 juveniles were evaluated in crayfish acclimated for 16 weeks to either 25ºC (temperature near optimum or 20ºC (marginal for the species. Additionally, the modulating effect of ecdsyone on acclimation was studied. After 12 weeks of exposure, weight gain of both experimental groups acclimated to 25ºC (control: C25, and ecdysone treated: E25 was significantly higher than that of those groups acclimated to 20ºC (C20 and E20. A total compensation in metabolic rate was seen after acclimation from 25ºC to 20ºC; for both the control group and the group treated with ecdysone. A Q10value significantly higher was only observed in the group acclimated to 20ºC and treated with ecdysone. A reduction of glycogen reserves in both hepatopancreas and muscle, as well as a lower protein content in muscle, was seen in both groups acclimated to 20ºC. Correspondingly, glycemia was always higher in these groups. Increased lipid levels were seen in the hepatopancreas of animals acclimated to 20ºC, while a higher lipid level was also observed in muscle at 20ºC, but only in ecdysone-treated crayfish.

  7. Adult neurogenesis in the crayfish brain: the hematopoietic anterior proliferation center has direct access to the brain and stem cell niche.

    Science.gov (United States)

    Chaves da Silva, Paula Grazielle; Benton, Jeanne L; Sandeman, David C; Beltz, Barbara S

    2013-04-01

    Neuronal stem cells residing in a niche on the surface of the adult crayfish (Procambarus clarkii) brain are not self-renewing. However, the neuronal precursors in the niche are not depleted despite continued neurogenesis and the exit of precursor cells from the niche throughout the organism's life. The neurogenic niche is therefore not a closed system, and we have previously proposed that the stem cell pool is replenished from the hematopoietic system. Noonin et al. (2012) demonstrated that the hematopoietic system in the crayfish Pacifastacus leniusculus includes an anterior proliferation center (APC) lying near the brain; they suggest that multipotent stem cells are concentrated in this region, and that the APC may provide neuronal stem cells for adult neurogenesis. The present study extends this work by describing the location and cellular organization of hematopoietic tissues in P. clarkii. We find that the APC lies within the cor frontale, or auxiliary heart, which pumps hemolymph to the brain and eyes through the cerebral and ophthalmic arteries, respectively. Vascular extensions of the cerebral artery converge on the neurogenic niche. APC cells lie in layered sheets within the cor frontale and form rosette-like structures reminiscent of stem cells in other developing tissues. We confirm here that APC cells in P. clarkii have characteristics of multipotent stem cells, and that their location within the cor frontale allows direct access to regions in the central nervous system in which adult neurogenesis occurs.

  8. Identification of two GH18 chitinase family genes and their use as targets for detection of the crayfish-plague oomycete Aphanomyces astaci

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    Bibars-Reiter Renè

    2009-08-01

    Full Text Available Abstract Background The oomycete Aphanomyces astaci is regarded as the causative agent of crayfish plague and represents an evident hazard for European crayfish species. Native crayfish populations infected with this pathogen suffer up to 100% mortality. The existence of multiple transmission paths necessitates the development of a reliable, robust and efficient test to detect the pathogen. Currently, A. astaci is diagnosed by a PCR-based assay that suffers from cross-reactivity to other species. We developed an alternative closed-tube assay for A. astaci, which achieves robustness through simultaneous amplification of multiple functionally constrained genes. Results Two novel constitutively expressed members of the glycosyl hydrolase (GH18 gene family of chitinases were isolated from the A. astaci strain Gb04. The primary amino acid sequence of these chitinase genes, termed CHI2 and CHI3, is composed of an N-terminal signal peptide directing the post-translational transport of the protein into the extracellular space, the catalytic GH18 domain, a proline-, serine-, and threonine-rich domain and a C-terminal cysteine-rich putative chitin-binding site. The A. astaci mycelium grown in a pepton-glucose medium showed significant temporal changes in steady-state CHI2 and CHI3 mRNA amounts indicating functional constraint. Their different temporal occurrence with maxima at 48 and 24 hours of incubation for CHI2 and CHI3, respectively, is in accordance with the multifunctionality of GH18 family members. To identify A. astaci-specific primer target sites in these novel genes, we determined the partial sequence homologs in the related oomycetes A. frigidophilus, A. invadans, A. helicoides, A. laevis, A. repetans, Achlya racemosa, Leptolegnia caudata, and Saprolegnia parasitica, as well as in the relevant fungi Fusarium solani and Trichosporon cutaneum. An A. astaci-specific primer pair targeting the novel genes CHI2 and CHI3 as well as CHI1 - a third GH

  9. RECENT SUSPECT CASES AND A PILOT DETECTION STUDY

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    KOZUBÍKOVÁ E.

    2006-01-01

    Full Text Available There are only very limited reports about the occurrence of the crayfish plague in Czechia. In recent years, mass mortalities of Astacus spp. with symptoms of possible crayfish plague were noticed in three streams in the country – two in Central Bohemia (1998-9 and one in Silesia (2004. Three dead individuals from the last outbreak were examined for the presence of the crayfish plague pathogen, Aphanomyces astaci, by observation of the presence of hyphae in their cuticle and by a PCR-based diagnostic method. In all three cases the detection was positive. Although causes of mass mortalities from two other localities lack such a direct confirmation, the indirect evidence supports the same conclusion. The main potential vector of A. astaci in Czechia is the American spiny-cheeck crayfish Orconectes limosus, widespread in large rivers of the western part of the country and in various isolated standing waters. Using the same molecular method, we investigated the presence of A. astaci in living O. limosus individuals from six localities (three running and three standing waters. The analysis indicated the presence of the pathogen in animals from five out of six investigated Orconectes populations. One of them is present in the stream where two European Astacus species had gone extinct in 1998-9. Our results suggest that the crayfish plague is still present in Czechia, and that populations of O. limosus represent a reservoir for the crayfish plague pathogen, which directly endangers populations of the native crayfish.

  10. Fatty acids and astaxanthin composition of two edible native Mexican crayfish Cambarellus (C. montezumae and Procambarus (M. bouvieri

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    Coral-Hinostroza, G.

    2016-09-01

    Full Text Available The content and composition of the fatty acids (FAs and astaxanthin (AST in the edible forms of crayfish: the whole animal of Cambarellus (C. montezumae, and the tail meat (TM of Procambarus (M. bouvieri were determined by GC and HPLC. The exoskeleton (EXK of P. (M. bouvieri was also studied. Unsaturated FAs, and mostly oleic acid (C18:1 n-9, were predominant in both edible forms. The contents of the polyunsaturated eicosapentaenoic (C20:5 n-3, EPA, arachidonic (C20:4 n-6, ARA and docosahexaenoic acid (C22:6 n-3, DHA, were higher in the TM of P. (M. bouvieri than in the complete C. (C. montezumae (p -1 and 66.3 ± 3.91 μg·g-1, and were composed mainly of AST ( > 79.50%. AST esters were enriched with saturated FAs in C. (C. montezumae and with PUFAs in EXK of P. (M. bouvieri. We conclude that both C. (C. montezumae and the TM of P. (M. bouvieri are traditional foods rich in n-3 PUFAs and C. (C. montezumae in AST. The EXK of P. (M. bouvieri is a rich potential source of AST, n-3 PUFAs, and the combination AST-DHA.Se determinó por GC y HPLC el contenido y composición de ácidos grasos (AGs y astaxantina (AST, en dos formas comestibles de acocil: el animal completo de Cambarellus (C. montezumae, y el músculo de la cola (MC de Procambarus (M. bouvieri. Adicionalmente, se estudió el exosqueleto (EXK de P. (M. bouvieri. En ambas formas comestibles predominaron los AGs insaturados. Los contenidos de ácido eicosapentaenoico (C20:5 n-3, EPA, araquidónico (C20:4 n-6, ARA y docosahexaenoico (C22: 6 n-3, DHA, fueron mayores en el MC que en C. (C montezumae (p -1 a 66.3 ± 3.9 μg·g-1, con predominancia de AST ( > 79.50%. Los ésteres de AST en C. (C. montezumae fueron enriquecidos con AGs saturados mientras que los del EXK de P. (M. bouvieri con AGs poliinsaturados. Se concluyó que tanto C. (C. montezumae como el MC de P. (M. bouvieri, son alimentos tradicionales ricos en PUFAs n-3, y C. (C. montezumae en AST. El EXK de P. (M. bouvieri abunda en

  11. Modification of sodium and potassium channel kinetics by diethyl ether and studies on sodium channel inactivation in the crayfish giant axon membrane

    Energy Technology Data Exchange (ETDEWEB)

    Bean, Bruce Palmer [Univ. of Rochester, NY (United States)

    1979-01-01

    The effects of ether and halothane on membrane currents in the voltage clamped crayfish giant axon membrane were investigated. Concentrations of ether up to 300 mM and of halothane up to 32 mM had no effect on resting potential or leakage conductance. Ether and halothane reduced the size of sodium currents without changing the voltage dependence of the peak currents or their reversal potential. Ether and halothane also produced a reversible, dose-dependent speeding of sodium current decay at all membrane potentials. Ether reduced the time constants for inactivation, and also shifted the midpoint of the steady-state inactivation curve in the hyperpolarizing direction. Potassium currents were smaller with ether present, with no change in the voltage dependence of steady-state currents. The activation of potassium channels was faster with ether present. There was no apparent change in the capacitance of the crayfish giant axon membrane with ether concentrations of up to 100 mM. Experiments on sodium channel inactivation kinetics were performed using 4-aminopyridine to block potassium currents. Sodium currents decayed with a time course generally fit well by a single exponential. The time constant of decay was a steep function of voltage, especially in the negative resistance region of the peak current vs voltage relation.The time course of inactivation was very similar to that of the decay of the current at the same potential. The measurement of steady-state inactivation curves with different test pulses showed no shifts along the voltage asix. The voltage-dependence of the integral of sodium conductance was measured to test models of sodium channel inactivation in which channels must open before inactivating; the results appear inconsistent with some of the simplest cases of such models.

  12. Vitellogenin levels in hemolymph, ovary and hepatopancreas of the freshwater crayfish Cherax quadricarinatus (Decapoda: Parastacidae during the reproductive cycle

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    Lilian E. Ferré

    2012-03-01

    Full Text Available The freshwater crayfish Cherax quadricarinatus is a tropical species of great interest for aquaculture. Vitellogenin (Vg, a lipoprotein precursor of the vitellum accumulated in spawned eggs, can be synthesized in the ovary and/or hepatopancreas of most crustaceans, being the hemolymph the way for transporting Vg throughout the reproductive cycle. Concentration of Vg in hemolymph, ovary and hepatopancreas of Cherax quadricarinatus adult females was measured by means of ELISA, specifically developed after purifying the native Vg. Measurements were made at four periods of the reproductive cycle: pre-reproductive, mid-reproductive, late reproductive and post-reproductive. Besides, both hepatosomatic (HSI and gonadosomatic (GSI indexes were determined in each period. Significant variations in Vg levels were detected in both hemolymph and hepatopancreas, being the highest values observed during the mid-reproductive period. Besides, such variations were positively correlated to the HSI. A positive correlation between Vg levels in hepatopancreas and ovary was also seen. These results support previous evidences about the central role of the hepatopancreas as a site of Vg synthesis in the studied species, together with the relevancy of hemolymph for transporting Vg from the hepatopancreas to the ovary. For aquaculture purposes, Vg monitoring in hemolymph could be used as a non-injurious method, to check the reproductive activity of C. quadricarinatus females.La langosta de agua dulce Cherax quadricarinatus es una especie tropical de gran interés para la acuicultura. Se midió la concentración de vitelogenina (Vg en hemolinfa, ovario y hepatopáncreas de hembras adultas de esta especie, por medio de ELISA. Las mediciones fueron hechas en los cuatro períodos del ciclo reproductivo: pre-reproductivo, reproductivo medio, reproductivo tardío y post-reproductivo. Se detectaron variaciones significativas en los niveles de Vg tanto en hemolinfa como en

  13. Present distribution and future spread of louisiana red swamp crayfish Procambarus clarkii (Crustacea, Decapoda, Astacida, Cambaridae in Britain : Implications for conservation of native species and habitats

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    Ellis A.

    2012-10-01

    Full Text Available The Louisiana red swamp crayfish Procambarus clarkii is highly invasive. It is now common in Europe where it is causing problems to native wildlife and structural damage to habitats. Procambarus clarkii was first recorded in Britain in 1991 and is currently found in the Hampstead Heath ponds and Regents Canal in London, as well as a small lake 15 km outside of Greater London. This paper considers how conditions in Britain affect the life cycle, breeding habits and potential range expansion of P. clarkii. Results of trapping surveys are presented in an effort to map the current distribution of P. clarkii and predict which areas it could colonise in the future. The ecological impact of potential colonisation is discussed by considering the impact P. clarkii has in mainland Europe. It is concluded that P. clarkii is likely to spread from Regents Canal into the nearby Brent, Crane, Colne, Lee and Thames catchments within 50 years. This time would be reduced significantly if further deliberate or accidental introductions by humans occur since this is deemed a far greater risk than natural expansion. P. clarkii is expected to have a negative impact on aquatic ecosystems in Britain and therefore tighter enforcement is needed to slow the spread of this species.

  14. Putative pacemakers in the eyestalk and brain of the crayfish Procambarus clarkii show circadian oscillations in levels of mRNA for crustacean hyperglycemic hormone.

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    Janikua Nelson-Mora

    Full Text Available Crustacean hyperglycemic hormone (CHH synthesizing cells in the optic lobe, one of the pacemakers of the circadian system, have been shown to be present in crayfish. However, the presence of CHH in the central brain, another putative pacemaker of the multi-oscillatory circadian system, of this decapod and its circadian transcription in the optic lobe and brain have yet to be explored. Therefore, using qualitative and quantitative PCR, we isolated and cloned a CHH mRNA fragment from two putative pacemakers of the multi-oscillatory circadian system of Procambarus clarkii, the optic lobe and the central brain. This CHH transcript synchronized to daily light-dark cycles and oscillated under dark, constant conditions demonstrating statistically significant daily and circadian rhythms in both structures. Furthermore, to investigate the presence of the peptide in the central brain of this decapod, we used immunohistochemical methods. Confocal microscopy revealed the presence of CHH-IR in fibers and cells of the protocerebral and tritocerebal clusters and neuropiles, particularly in some neurons located in clusters 6, 14, 15 and 17. The presence of CHH positive neurons in structures of P. clarkii where clock proteins have been reported suggests a relationship between the circadian clockwork and CHH. This work provides new insights into the circadian regulation of CHH, a pleiotropic hormone that regulates many physiological processes such as glucose metabolism and osmoregulatory responses to stress.

  15. Putative pacemakers in the eyestalk and brain of the crayfish Procambarus clarkii show circadian oscillations in levels of mRNA for crustacean hyperglycemic hormone.

    Science.gov (United States)

    Nelson-Mora, Janikua; Prieto-Sagredo, Julio; Loredo-Ranjel, Rosaura; Fanjul-Moles, María Luisa

    2013-01-01

    Crustacean hyperglycemic hormone (CHH) synthesizing cells in the optic lobe, one of the pacemakers of the circadian system, have been shown to be present in crayfish. However, the presence of CHH in the central brain, another putative pacemaker of the multi-oscillatory circadian system, of this decapod and its circadian transcription in the optic lobe and brain have yet to be explored. Therefore, using qualitative and quantitative PCR, we isolated and cloned a CHH mRNA fragment from two putative pacemakers of the multi-oscillatory circadian system of Procambarus clarkii, the optic lobe and the central brain. This CHH transcript synchronized to daily light-dark cycles and oscillated under dark, constant conditions demonstrating statistically significant daily and circadian rhythms in both structures. Furthermore, to investigate the presence of the peptide in the central brain of this decapod, we used immunohistochemical methods. Confocal microscopy revealed the presence of CHH-IR in fibers and cells of the protocerebral and tritocerebal clusters and neuropiles, particularly in some neurons located in clusters 6, 14, 15 and 17. The presence of CHH positive neurons in structures of P. clarkii where clock proteins have been reported suggests a relationship between the circadian clockwork and CHH. This work provides new insights into the circadian regulation of CHH, a pleiotropic hormone that regulates many physiological processes such as glucose metabolism and osmoregulatory responses to stress.

  16. Microsatellite evidence of dispersal mechanism of red swamp crayfish (Procambarus clarkii) in the Pearl River basin and implications for its management.

    Science.gov (United States)

    Huang, Jinlong; Tang, Shaoqing; Cai, Fengjin; Lin, Yanfang; Wu, Zhengjun

    2017-08-15

    Discerning the dispersal patterns of invasive species is critically important for the design of effective management strategies and the development of appropriate theoretical models predicting the spatial expansion of introduced populations. Post-introduction dispersal may occur naturally or via human transport, but for many organisms, assessing the relative contribution of each of these factors is difficult using traditional methods. Here, we explored the genetic patterns associated with the spread of red swamp crayfish (Procambarus clarkii) among 21 populations in the Pearl River basin and 2 peripheral populations in the Yangtze River basin. We found the genetic diversity of P. clarkii in the Pearl River basin was somewhat lower than in the Yangtze River basin. We also found (1) there was significant genetic differentiation between populations, (2) genetic differentiation was not related to geographic distance (i.e., isolation by distance), and (3) a Bayesian assignment analysis revealed three distinct genetic clusters and genetic admixture. Our results therefore provide evidence that human-mediated multiple introductions occurred in the Pearl River basin. Anthropogenic activities such as commercial transportation were likely responsible for the long-distance dispersal of P. clarkii. This study provides useful information for developing management strategies.

  17. The Nature and Origin of the Epidermal Scales of Notodactylus handschini--an Unusual Temnocephalid Turbellarian Ectosymbiotic on Crayfish from Northern Queensland.

    Science.gov (United States)

    Jennings, J B; Cannon, L R G; Hick, A J

    1992-02-01

    The temnocephalid Notodactylus handschini, ectosymbiotic on the crayfish Cherax quadricarinatus from northern Queensland, is unique among known turbellarians in having its dorsal epidermis covered by rows of closely adjacent scales. These are borne on epidermal plinths separated by arthrodial gutters and are up to 100 μm tall with rhombic bases 40-55 μm by 15-20 μm. Above the bases, the rhombic cross section gradually becomes oval so that the scales are essentially elongate conoids, the slender tips of which curve inwards towards the worm's mid-line. In mature worms, the more median scales may be reduced distally into squat truncated cones only 40-50 μm tall. The scales consist of glycoprotein; rhabdites discharged from cells in the dorsal parenchyma contribute the protein, whereas the carbohydrate component probably comes from the glycocalyxes of the epidermal microvilli. The latter act as templates around which the glycoprotein mixture coalesces, seemingly by a simple tanning process, into tightly packed tubes 180-200 nm in diameter with walls 40-45 nm thick. The scales lack any limiting wall or membrane other than a loose amorphous layer, 90-150 nm thick, formed by disintegration of the tubes distally and compensated for by continuous growth basally. Each scale is attached to its epidermal plinth by the bases of its constituent tubes ensheathing the microvilli; attachment is reinforced by cross-striated fibrils, probably collagen, embedded in the epidermis and inserted between the microvilli into tube bases near the scales' corners. Scale surfaces bear rich growths of microorganisms. The use of rhabdites to form permanent scales is probably an adaptation to the worm's unusual sedentary habit; it supports, paradoxically, an earlier hypothesis that the primary function of rhabdites in turbellarians other than temnocephalids is to provide a continuously renewable coating compatible with epidermal ciliation.

  18. Differential effects of silencing crustacean hyperglycemic hormone gene expression on the metabolic profiles of the muscle and hepatopancreas in the crayfish Procambarus clarkii.

    Directory of Open Access Journals (Sweden)

    Wenfeng Li

    Full Text Available In order to functionally characterize the metabolic roles of crustacean hyperglycemic hormone (CHH, gene expression of CHH in the crayfish (Procambarus clarkii was knocked down by in vivo injection of CHH double-stranded RNA (dsRNA, followed by metabolomic analysis of 2 CHH target tissues (the muscle and hepatopancreas using nuclear magnetic resonance spectroscopy. Compared to the levels in untreated and saline-injected (SAI animals, levels of CHH transcript, but not those of molt-inhibiting hormone (a CHH-family peptide, in the eyestalk ganglia of CHH dsRNA-injected (DSI animals were significantly decreased at 24, 48, and 72 hour post injection (hpi, with concomitant changes in levels of CHH peptide in the sinus gland (a neurohemal organ and hemolymph. Green fluorescence protein (GFP dsRNA failed to affect levels of CHH transcript in the eyestalk ganglia of GFP DSI animals. Number of metabolites whose levels were significantly changed by CHH dsRNA was 149 and 181 in the muscle and 24 and 12 in the hepatopancreas, at 24 and 48 hpi, respectively. Principal component analysis of these metabolites show that metabolic effects of silencing CHH gene expression were more pronounced in the muscle (with the cluster of CHH DSI group clearly being separated from that of SAI group at 24 hpi than in the hepatopancreas. Moreover, pathway analysis of the metabolites closely related to carbohydrate and energy metabolism indicate that, for CHH DSI animals at 24 hpi, metabolic profile of the muscle was characterized by reduced synthesis of NAD+ and adenine ribonucleotides, diminished levels of ATP, lower rate of utilization of carbohydrates through glycolysis, and a partially rescued TCA cycle, whereas that of the hepatopancreas by unaffected levels of ATP, lower rate of utilization of carbohydrates, and increased levels of ketone bodies. The combined results of metabolic changes in response to silenced CHH gene expression reveal that metabolic functions of CHH

  19. Differential effects of silencing crustacean hyperglycemic hormone gene expression on the metabolic profiles of the muscle and hepatopancreas in the crayfish Procambarus clarkii.

    Science.gov (United States)

    Li, Wenfeng; Chiu, Kuo-Hsun; Tien, Yi-Chun; Tsai, Shih-Fu; Shih, Li-Jane; Lee, Chien-Hsun; Toullec, Jean-Yves; Lee, Chi-Ying

    2017-01-01

    In order to functionally characterize the metabolic roles of crustacean hyperglycemic hormone (CHH), gene expression of CHH in the crayfish (Procambarus clarkii) was knocked down by in vivo injection of CHH double-stranded RNA (dsRNA), followed by metabolomic analysis of 2 CHH target tissues (the muscle and hepatopancreas) using nuclear magnetic resonance spectroscopy. Compared to the levels in untreated and saline-injected (SAI) animals, levels of CHH transcript, but not those of molt-inhibiting hormone (a CHH-family peptide), in the eyestalk ganglia of CHH dsRNA-injected (DSI) animals were significantly decreased at 24, 48, and 72 hour post injection (hpi), with concomitant changes in levels of CHH peptide in the sinus gland (a neurohemal organ) and hemolymph. Green fluorescence protein (GFP) dsRNA failed to affect levels of CHH transcript in the eyestalk ganglia of GFP DSI animals. Number of metabolites whose levels were significantly changed by CHH dsRNA was 149 and 181 in the muscle and 24 and 12 in the hepatopancreas, at 24 and 48 hpi, respectively. Principal component analysis of these metabolites show that metabolic effects of silencing CHH gene expression were more pronounced in the muscle (with the cluster of CHH DSI group clearly being separated from that of SAI group at 24 hpi) than in the hepatopancreas. Moreover, pathway analysis of the metabolites closely related to carbohydrate and energy metabolism indicate that, for CHH DSI animals at 24 hpi, metabolic profile of the muscle was characterized by reduced synthesis of NAD+ and adenine ribonucleotides, diminished levels of ATP, lower rate of utilization of carbohydrates through glycolysis, and a partially rescued TCA cycle, whereas that of the hepatopancreas by unaffected levels of ATP, lower rate of utilization of carbohydrates, and increased levels of ketone bodies. The combined results of metabolic changes in response to silenced CHH gene expression reveal that metabolic functions of CHH on the

  20. Comparison of the response (in terms of accumulation, cellular and genetic impacts) of the crayfish Procambarus clarkii after exposure to a metallic pollutant (cadmium) and to a radiological pollutant (uranium 238 and 233)

    International Nuclear Information System (INIS)

    Al Kaddissi, S.

    2012-01-01

    The study of the effects of radionuclides and metals on organisms is necessary for the evaluation of their toxicity and their ecological threats. We first aimed to study the impacts of cadmium (Cd) and Uranium (U) on different biological levels of the crayfish Procambarus clarkii after acute and chronic exposures. We evaluated their impacts on mitochondria, oxidative stress responses, on histological structures, and the survival rates. We tried to connect these effects between them and to the bioaccumulation in the gills and the hepato pancreas. We also tried to discriminate the chemo and the radiotoxicity of U by exposing crayfish to either depleted or enriched U ( 233 U: presenting a higher specific activity) using the same criteria of effects. We demonstrated that the gene mt encoding for the metallothionein was always over-expressed in the presence of Cd. Therefore, it seems to be a good bio-marker of Cd toxicity in P. clarkii. The follow up of mitochondrial genes expressions (12s, atp6 and cox1), showed that both metals affect mitochondria and that their mechanisms of action do not seem to be always the same. We also observed that U generates more oxidative stress than Cd when comparing the expression levels of genes encoding for antioxidants (sod (Mn) and mt) and the enzymatic activities of superoxide dismutase, the catalase, the glutathione peroxidase and the glutathione S transferase. However, the symptoms of histo-pathological damages after Cd and U contamination were similar in both conditions. After comparing the survival rates of the crayfish, we concluded that Cd was more toxic than the radioelement. Moreover, we demonstrated that the toxic effect of U on P. clarkii exposed to a low environmental concentration is mainly due to its chemo-toxicity rather than to its radiotoxicity. We established that, the molecular answers vary according to the intensity and the duration of the chemical stress applied to the organisms. We suggested the use of the

  1. Application of D-Crustacean Hyperglycemic Hormone Induces Peptidases Transcription and Suppresses Glycolysis-Related Transcripts in the Hepatopancreas of the Crayfish Pontastacus leptodactylus — Results of a Transcriptomic Study

    Science.gov (United States)

    De Moro, Gianluca; Gerdol, Marco; Guarnaccia, Corrado; Mosco, Alessandro; Pallavicini, Alberto; Giulianini, Piero Giulio

    2013-01-01

    The crustacean Hyperglycemic Hormone (cHH) is a neuropeptide present in many decapods. Two different chiral isomers are simultaneously present in Astacid crayfish and their specific biological functions are still poorly understood. The present study is aimed at better understanding the potentially different effect of each of the isomers on the hepatopancreatic gene expression profile in the crayfish Pontastacus leptodactylus, in the context of short term hyperglycemia. Hence, two different chemically synthesized cHH enantiomers, containing either L- or D-Phe3, were injected to the circulation of intermolt females following removal of their X organ-Sinus gland complex. The effects triggered by the injection of the two alternate isomers were detected after one hour through measurement of circulating glucose levels. Triggered changes of the transcriptome expression profile in the hepatopancreas were analyzed by RNA-seq. A whole transcriptome shotgun sequence assembly provided the assumedly complete transcriptome of P. leptodactylus hepatopancreas, followed by RNA-seq analysis of changes in the expression level of many genes caused by the application of each of the hormone isomers. Circulating glucose levels were much higher in response to the D-isoform than to the L-isoform injection, one hour from injection. Similarly, the RNA-seq analysis confirmed a stronger effect on gene expression following the administration of D-cHH, while just limited alterations were caused by the L-isomer. These findings demonstrated a more prominent short term effect of the D-cHH on the transcription profile and shed light on the effect of the D-isomer on specific functional gene groups. Another contribution of the study is the construction of a de novo assembly of the hepatopancreas transcriptome, consisting of 39,935 contigs, that dramatically increases the molecular information available for this species and for crustaceans in general, providing an efficient tool for studying gene

  2. Application of D-Crustacean Hyperglycemic Hormone Induces Peptidases Transcription and Suppresses Glycolysis-Related Transcripts in the Hepatopancreas of the Crayfish Pontastacus leptodactylus - Results of a Transcriptomic Study.

    Directory of Open Access Journals (Sweden)

    Chiara Manfrin

    Full Text Available The crustacean Hyperglycemic Hormone (cHH is a neuropeptide present in many decapods. Two different chiral isomers are simultaneously present in Astacid crayfish and their specific biological functions are still poorly understood. The present study is aimed at better understanding the potentially different effect of each of the isomers on the hepatopancreatic gene expression profile in the crayfish Pontastacus leptodactylus, in the context of short term hyperglycemia. Hence, two different chemically synthesized cHH enantiomers, containing either L- or D-Phe(3, were injected to the circulation of intermolt females following removal of their X organ-Sinus gland complex. The effects triggered by the injection of the two alternate isomers were detected after one hour through measurement of circulating glucose levels. Triggered changes of the transcriptome expression profile in the hepatopancreas were analyzed by RNA-seq. A whole transcriptome shotgun sequence assembly provided the assumedly complete transcriptome of P. leptodactylus hepatopancreas, followed by RNA-seq analysis of changes in the expression level of many genes caused by the application of each of the hormone isomers. Circulating glucose levels were much higher in response to the D-isoform than to the L-isoform injection, one hour from injection. Similarly, the RNA-seq analysis confirmed a stronger effect on gene expression following the administration of D-cHH, while just limited alterations were caused by the L-isomer. These findings demonstrated a more prominent short term effect of the D-cHH on the transcription profile and shed light on the effect of the D-isomer on specific functional gene groups. Another contribution of the study is the construction of a de novo assembly of the hepatopancreas transcriptome, consisting of 39,935 contigs, that dramatically increases the molecular information available for this species and for crustaceans in general, providing an efficient tool for

  3. Regina rigida (glossy crayfish snake)

    Science.gov (United States)

    David A. Steen; James A. Stiles; Sierra H. Stiles; Craig Guyer; Josh B. Pierce; D. Craig Rudolph; Lora L. Smith

    2011-01-01

    The overland movements and upland habitat use of wetland-associated reptiles has important conservation implications (Semlitsch and Bodie 2003. Conserv. BioI. 17:1219-1228). However, for many species, particularly snakes, we lack a basic understanding of spatial ecology and habitat use. Regina rigida is a poorly known species for which "observations of any kind...

  4. Sensory Systems and Environmental Change on Behavior during Social Interactions

    Directory of Open Access Journals (Sweden)

    S. M. Bierbower

    2013-01-01

    Full Text Available The impact of environmental conditions for transmitting sensory cues and the ability of crayfish to utilize olfaction and vision were examined in regards to social interactive behavior. The duration and intensity of interactions were examined for conspecific crayfish with different sensory abilities. Normally, vision and chemosensory have roles in agonistic communication of Procambarus clarkii; however, for the blind cave crayfish (Orconectes australis packardi, that lack visual capabilities, olfaction is assumed to be the primary sensory modality. To test this, we paired conspecifics in water and out of water in the presence and absence of white light to examine interactive behaviors when these various sensory modalities are altered. For sighted crayfish, in white light, interactions occurred and escalated; however, when the water was removed, interactions and aggressiveness decreased, but, there was an increase in visual displays out of the water. The loss of olfaction abilities for blind cave and sighted crayfish produced fewer social interactions. The importance of environmental conditions is illustrated for social interactions among sighted and blind crayfish. Importantly, this study shows the relevance in the ecological arena in nature for species survival and how environmental changes disrupt innate behaviors.

  5. On involvement of transcription factors nuclear factor kappa-light-chain-enhancer of activated B cells, activator protein-1 and signal transducer and activator of transcription-3 in photodynamic therapy-induced death of crayfish neurons and satellite glial cells

    Science.gov (United States)

    Berezhnaya, Elena; Neginskaya, Marya; Kovaleva, Vera; Sharifulina, Svetlana; Ischenko, Irina; Komandirov, Maxim; Rudkovskii, Mikhail; Uzdensky, Anatoly B.

    2015-07-01

    Photodynamic therapy (PDT) is currently used in the treatment of brain tumors. However, not only malignant cells but also neighboring normal neurons and glial cells are damaged during PDT. In order to study the potential role of transcription factors-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), activator protein (AP-1), and signal transducer and activator of transcription-3 (STAT-3)-in photodynamic injury of normal neurons and glia, we photosensitized the isolated crayfish mechanoreceptor consisting of a single sensory neuron enveloped by glial cells. Application of different inhibitors and activators showed that transcription factors NF-κB (inhibitors caffeic acid phenethyl ester and parthenolide, activator betulinic acid), AP-1 (inhibitor SR11302), and STAT-3 (inhibitors stattic and cucurbitacine) influenced PDT-induced death and survival of neurons and glial cells in different ways. These experiments indicated involvement of NF-κB in PDT-induced necrosis of neurons and apoptosis of glial cells. However, in glial cells, it played the antinecrotic role. AP-1 was not involved in PDT-induced necrosis of neurons and glia, but mediated glial apoptosis. STAT-3 was involved in PDT-induced apoptosis of glial cells and necrosis of neurons and glia. Therefore, signaling pathways that regulate cell death and survival in neurons and glial cells are different. Using various inhibitors or activators of transcription factors, one can differently influence the sensitivity and resistance of neurons and glial cells to PDT.

  6. On involvement of transcription factors nuclear factor kappa-light-chain-enhancer of activated B cells, activator protein-1 and signal transducer and activator of transcription-3 in photodynamic therapy-induced death of crayfish neurons and satellite glial cells.

    Science.gov (United States)

    Berezhnaya, Elena; Neginskaya, Marya; Kovaleva, Vera; Sharifulina, Svetlana; Ischenko, Irina; Komandirov, Maxim; Rudkovskii, Mikhail; Uzdensky, Anatoly B

    2015-07-01

    Photodynamic therapy (PDT) is currently used in the treatment of brain tumors. However, not only malignant cells but also neighboring normal neurons and glial cells are damaged during PDT. In order to study the potential role of transcription factors-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), activator protein (AP-1), and signal transducer and activator of transcription-3 (STAT-3)-in photodynamic injury of normal neurons and glia, we photosensitized the isolated crayfish mechanoreceptor consisting of a single sensory neuron enveloped by glial cells. Application of different inhibitors and activators showed that transcription factors NF-κB (inhibitors caffeic acid phenethyl ester and parthenolide, activator betulinic acid), AP-1 (inhibitor SR11302), and STAT-3 (inhibitors stattic and cucurbitacine) influenced PDT-induced death and survival of neurons and glial cells in different ways. These experiments indicated involvement of NF-κB in PDT-induced necrosis of neurons and apoptosis of glial cells. However, in glial cells, it played the antinecrotic role. AP-1 was not involved in PDT-induced necrosis of neurons and glia, but mediated glial apoptosis. STAT-3 was involved in PDT-induced apoptosis of glial cells and necrosis of neurons and glia. Therefore, signaling pathways that regulate cell death and survival in neurons and glial cells are different. Using various inhibitors or activators of transcription factors, one can differently influence the sensitivity and resistance of neurons and glial cells to PDT.

  7. Cultivo de camarón de río Samastacus spinifrons: ¿una nueva alternativa para la diversificación de la acuicultura chilena? Culturing freshwater crayfish Samastacus spinifrons: a new alternative for diversifying Chilean aquaculture?

    Directory of Open Access Journals (Sweden)

    Erich Rudolph

    2010-01-01

    Full Text Available El camarón de río del sur Samastacus spinifrons, es una de las seis especies de la Familia Parastacidae (Crustácea, Decapoda, Astacidea que habita las aguas dulces de Chile desde el río Aconcagua hasta la península de Taitao, y actualmente, la única que es considerada atractiva para la acuicultura nacional. En este artículo se revisa su potencial para la acuicultura con fines comerciales o de repoblamiento. Para ello se analizan: a las ventajas y desventajas biológicas de esta especie ante eventuales actividades de cultivo en confinamiento; b las experiencias de cultivo que a la fecha se han efectuado en Chile haciendo énfasis en sus respectivos aportes; y, c las probables causas que han impedido que su cultivo se consolide en el país. Finalmente, de acuerdo a los análisis antes señalados se plantea una propuesta de cultivo que se considera la más adecuada para S. spinifrons.The freshwater crayfish Samastacus spinifrons, is one of six species of the Family Parastacidae (Crustácea, Decapoda, Astacidea inhabiting freshwaters in Chile from the Aconcagua River to the Taitao Península, and the only one that is currently considered attractive for national aquaculture. In this article, we review the potential of this species for aquaculture with commercial or restocking purposes. For this, we analyze: a the species' biological advantages and disadvantages in an eventual situation of confined culture; b previous culturing experiences carried out in Chile, with an emphasis on their respective contributions; and c the causes that were likely to have prevented the consolidation of culturing this species in Chile. Finally, the above analyses provided the basis for our proposal of the most appropriate way to culture S. spinifrons.

  8. Seasonal variations in the intermediate metabolism of the crayfish Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae in the natural environment and experimental culture Variações sazonais do metabolismo intermediário do lagostim Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae no seu ambiente natural e em cultura experimental

    Directory of Open Access Journals (Sweden)

    Bibiana K. Dutra

    2008-09-01

    Full Text Available The goal of this study was to evaluate the effects of seasonal variations on energy metabolism in different tissues of the freshwater crayfish Parastacus brasiliensis (von Martens, 1869. Crayfish were collected monthly from January 2001 to January 2003 in São Francisco de Paula, Rio Grande do Sul, Brazil, in a stream and in a culture tank. Haemolymph samples were collected from each crayfish in the field with a syringe, by puncturing the membrane at the base of the chelipeds. Hepatopancreas, gills, and abdominal muscle were removed for determination of free glucose, glycogen, total lipids, and triglycerides. The haemolymph samples were used for determination of glucose, total proteins, total lipids, and triglycerides. Statistical analysis revealed significant differences in biochemical composition in crayfish collected in the stream compared to the experimental tank during the year, principally in glucose and triglycerides in haemolymph, glycogen and total lipids in all tissues study, and triglycerides only in abdominal muscle. The regular food intake partially modified these seasonal variations of the metabolic pattern. Environmental conditions (e.g., food availability and water temperature and reproductive period appeared to be the main factors influencing the seasonal patterns of variation in energy metabolism.O objetivo deste estudo foi avaliar o efeito das variações sazonais no metabolismo energético em diferentes tecidos do lagostim de água-doce Parastacus brasiliensis (von Martens, 1869. Os lagostins foram coletados mensalmente de Janeiro de 2001 a Janeiro de 2003 em São Francisco de Paula, Rio Grande do Sul, Brasil, no riacho e no tanque de cultivo. Amostras de hemolinfa foram coletadas de cada lagostim em campo com seringa, por punção na membrana da base dos quelípodos. Hepatopâncreas, brânquias e músculo abdominal foram removidos para a determinação dos níveis de glicose livre, de glicogênio, de lipídios totais e de

  9. Earliest evidence for human consumption of crayfish

    Czech Academy of Sciences Publication Activity Database

    Patoka, J.; Nývltová Fišáková, Miriam; Kalous, L.; Škrdla, Petr; Kuča, M.

    2014-01-01

    Roč. 87, č. 13 (2014), s. 1578-1585 ISSN 0011-216X Institutional research plan: CEZ:AV0Z80010507 Institutional support: RVO:68081758 Keywords : Crustaceans * anthropology of food * consumption * Small game * Neolithic Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 0.473, year: 2014

  10. Relación biogeográfica entre cangrejos dulceacuícolas y acociles a lo largo de la zona mexicana de transición: revaluación de la hipótesis de Rodríguez (1986 Biogeographic relationship of freshwater crabs and crayfish along the Mexican transition zone: reevaluating Rodríguez (1986 hypothesis

    Directory of Open Access Journals (Sweden)

    Fernando Álvarez

    2012-12-01

    Full Text Available A partir de la hipótesis planteada por Rodríguez (1986 sobre una posible exclusión biogeográfica entre acociles de la familia Cambaridae y cangrejos de agua dulce de la familia Pseudothelphusidae a lo largo del centro y sur de México, se han hecho varios estudios que toman en cuenta este patrón. Sin embargo, no se han examinado los patrones de distribución de estos grupos ni cuáles son las zonas ni a qué grado se da el traslape o contacto de las 2 distribuciones. Se construyeron 2 bases de datos, una con más de 1 400 registros de las especies de la familia Cambaridae y otra con más de 400 registros de cangrejos de la familia Pseudothelphusidae. Se construyeron mapas de distribución y se identificaron 3 regiones donde el contacto es evidente: el eje neovolcánico, la región de Los Tuxtlas, Veracruz y el estado de Chiapas. Los resultados muestran grandes zonas de contacto en las cuales tanto acociles como cangrejos pueden estar en la misma localidad y en el mismo cuerpo de agua o pueden estar en 2 localidades muy cercanas pero con una diferencia altitudinal. En general, los acociles tienden a distribuirse a mayores altitudes que los cangrejos. Aunado a los patrones de distribución, se discute que aunque los 2 grupos estén presentes en la misma localidad y en el mismo cuerpo de agua, el microhábitat que ocupa cada uno es distinto, por lo que se sugiere que la interferencia entre ellos será poca o nula.After Rodríguez (1986 hypothesis on the possible biogeographic exclusion between crayfish of the family Cambaridae and freshwater crabs of the family Pseudothelphusidae throughout central and southern Mexico, several studies have considered it as a real pattern. However, the distribution patterns of both groups have not been examined, nor in what areas and to what extent the overlap of the 2 distributions occurs. Two data bases were compiled, one with more than 1 400 records of the species of the family Cambaridae and a second one

  11. Crayfish in Czech cultural space: the longest documented relationship between humans and crayfish in Europe

    Czech Academy of Sciences Publication Activity Database

    Patoka, J.; Kocánová, Barbora; Kalous, L.

    2016-01-01

    Roč. 417, č. 5 (2016), s. 1-9 ISSN 1961-9502 Institutional support: RVO:67985955 Keywords : Freshwater invertebrate * exploitation * history * aquaculture * Czech Republic Subject RIV: AB - History Impact factor: 1.217, year: 2016 https://www.kmae-journal.org/articles/kmae/full_html/2016/01/kmae150112/kmae150112.html

  12. Mercury bioaccumulation and biomagnification in Ozark stream ecosystems

    Science.gov (United States)

    Schmitt, Christopher J.; Stricker, Craig A.; Brumbaugh, William G.

    2011-01-01

    Crayfish (Orconectes spp.), Asian clam (Corbicula fluminea), northern hog sucker (hog sucker; Hypentelium nigricans), and smallmouth bass (smallmouth; Micropterus dolomieu) from streams in southeastern Missouri (USA) were analyzed for total mercury (HgT) and for stable isotopes of carbon (δ13C), nitrogen (δ15N), and sulfur (δ34S) to discern Hg transfer pathways. HgT concentrations were generally lowest in crayfish (0.005–0.112 μg/g dw) and highest in smallmouth (0.093–4.041 μg/g dw), as was δ15N. HgT was also lower and δ15N was higher in all biota from a stream draining a more heavily populated historical lead–zinc mining area than from similar sites with mostly undeveloped forested watersheds. δ13C in biota was lowest at spring-influenced sites, reflecting CO2 inputs and temperature influences, and δ34S increased from south to north in all taxa. However, HgT was not strongly correlated with either δ13C or δ34S in biota. Trophic position (TP) computed from crayfish δ15N was lower in hog suckers (mean=2.8) than in smallmouth (mean=3.2), but not at all sites. HgT, δ13C, δ34S, and TP in hog suckers increased with total length (length) at some sites, indicating site-specific ontogenetic diet shifts. Changes with length were less evident in smallmouth. Length-adjusted HgT site means in both species were strongly correlated with HgT in crayfish (r2=0.97, PCorbicula (r2=0.02, P>0.05). ANCOVA and regression models incorporating only TP and, for hog suckers, length, accurately and precisely predicted HgT concentrations in both fish species from all locations. Although low compared to many areas of the USA, HgT (and therefore methylmercury) concentrations in smallmouth and hog suckers are sufficiently high to represent a threat to human health and wildlife. Our data indicate that in Ozark streams, Hg concentrations in crayfish are at least partly determined by their diet, with concentrations in hog suckers, smallmouth, and possibly other higher

  13. Fatty acids and astaxanthin composition of two edible native Mexican crayfish Cambarellus (C.) montezumae and Procambarus (M.) bouvieri; Composición de ácidos grasos y astaxantina de dos especies comestibles de acociles nativos de México, Cambarellus (C.) montezumae y Procambarus.

    Energy Technology Data Exchange (ETDEWEB)

    Coral-Hinostroza, G.; Diaz-Martinez, M.; Huberman, A.; Silencio-Barrita, J.L.

    2016-07-01

    The content and composition of the fatty acids (F As) and astaxanthin (AST) in the edible forms of crayfish: the whole animal of Cambarellus (C.) montezumae, and the tail meat (TM) of Procambarus (M.) bouvieri were determined by GC and HPLC. The exoskeleton (EXK) of P. (M.) bouvieri was also studied. Unsaturated FAs, and mostly oleic acid (C18:1 n-9), were predominant in both edible forms. The contents of the polyunsaturated eicosapentaenoic (C20:5 n-3, EPA), arachidonic (C20:4 n-6, ARA) and docosahexaenoic acid (C22:6 n-3, DHA), were higher in the TM of P. (M.) bouvieri than in the complete C. (C.) montezumae (p<0.05). Total carotenoids ranged between 2.31 ± 0.33 μg·g−1 and 66.3 ± 3.91 μg·g−1, and were composed mainly of AST (>79.50%). AST esters were enriched with saturated FAs in C. (C.) montezumae and with PUFAs in EXK of P. (M.) bouvieri. We conclude that both C. (C.) montezumae and the TM of P. (M.) bouvieri are traditional foods rich in n-3 PUFAs and C. (C.) montezumae in AST. The EXK of P. (M.) bouvieri is a rich potential source of AST, n-3 PUFAs, and the combination AST-DHA. [Spanish] Se determinó por GC y HPLC el contenido y composición de ácidos grasos (AGs) y astaxantina (AST), en dos formas comestibles de acocil: el animal completo de Cambarellus (C.) montezumae, y el músculo de la cola (MC) de Procambarus (M.) bouvieri. Adicionalmente, se estudió el exosqueleto (EXK) de P. (M.) bouvieri. En ambas formas comestibles predominaron los AGs insaturados. Los contenidos de ácido eicosapentaenoico (C20:5 n-3, EPA), araquidónico (C20:4 n-6, ARA) y docosahexaenoico (C22: 6 n-3, DHA), fueron mayores en el MC que en C. (C) montezumae (p<0,05). Los carotenoides totales oscilaron de 2.3 ± 0.3 μg·g−1 a 66.3 ± 3.9 μg·g−1, con predominancia de AST (>79.50%). Los ésteres de AST en C. (C.) montezumae fueron enriquecidos con AGs saturados mientras que los del EXK de P. (M.) bouvieri con AGs poliinsaturados. Se concluyó que tanto C. (C

  14. Comparative analysis of crayfish marketing in selected markets of ...

    African Journals Online (AJOL)

    Data analyses were carried out with the use of such statistical tools like bivirate analysis, efficiency ratio, marketing margin and regression analysis. The results show that selling and purchasing prices had weak correlation between the markets in Akwa Ibom and Abia states, implying low level of market integration.

  15. Hydrocarbon accumulation and discharge by the crayfish in some ...

    African Journals Online (AJOL)

    Research on petroleum hydrocarbon accumulation and discharge by marine invertebrates received ... Biological effects of oil pollution in freshwater ecosystems have been studied [14-16], however, little literature data are .... Nelson-Smith, A. Oil Pollution and Marine Biology, Plenum Press: New York; 1973. 6. Varanasi, U.

  16. Digestibilidade aparente da energia e proteína das farinhas de resíduo da filetagem da tilápia do Nilo (Oreochromis niloticus e da corvina (Plagioscion squamosissimus e farinha integral do camarão canela (Macrobrachium amazonicum para a tilápia do Nilo Apparent digestibility of energy and protein of tilapia (Oreochromis niloticus and corvina (Plagioscion squamosissimus by-product meal, and canela crayfish (Macrobrachium amazonicum meal for Nile

    Directory of Open Access Journals (Sweden)

    Wilson Rogério Boscolo

    2004-02-01

    Full Text Available O experimento foi conduzido objetivando determinar os coeficientes de digestibilidade aparente (CDa da energia bruta (EB e proteína bruta (PB, das farinhas de peixe obtidas a partir de resíduos de filetagem da corvina (FC, resíduos da filetagem da Tilápia (FT e farinha integral de camarão canela (FM para tilápia do Nilo. Foram utilizados 40 peixes revertidos sexualmente, com peso médio de 40 g, acondicionados em um tanque de alimentação de 500L. A coleta de fezes foi feita em duas cubas cilíndricas com fundo cônico, de 150L. A determinação dos CDa foi feita por metodologia indireta, tendo sido utilizado 0,1% de óxido crômico (Cr2O3, como indicador incorporado à ração. As médias de temperatura, oxigênio dissolvido, pH e condutividade elétrica, durante o período experimental, foram de 28,5 ± 0,5ºC; 3,57 ± 0,12 mg/L; 7,21 ± 0,03; e 0,18 ± 0,01 mS/cm, respectivamente. Os CDa para a PB e EB foram de 70,67 e 54,45 para FC; 67,09 e 48,52 para FT; e 88,79 e 68,38 para FM, apresentando valores de proteína (% e energia (kcal/kg digestíveis, na matéria natural, de 37,50 e 2107,46 para FC; 28,72 e 1927,18 para a FT; e 53,74 e 2763,23 para FM, respectivamente. Os alimentos estudados têm potencial para utilização na alimentação da tilápia do Nilo, sendo necessária a determinação dos seus níveis de inclusão em rações para as diferentes fases de cultivo da espécie.The trial was conducted to evaluate the apparent digestibility coefficients (CDa of gross energy (EB and crude protein (PB of tilapia (FT and corvina (FC processing by-product meal, and canela crayfish (Macrobrachium amazonicum meal (FM, for Nile tilapia fingerlings. Forty sexual reverted fishes, with average weight of 40 g, were allotted to 500 L feeding tanks. Feces collection was performed at two 150 L conical tanks. CDa was evaluated by an indirect method, with 0.1% chromic oxide (Cr2O3 as the indicator. Average temperature, dissolved oxygen, pH and

  17. Spatial distribution of radionuclides in Lake Michigan biota near the Big Rock Point Nuclear Plant

    International Nuclear Information System (INIS)

    Wahlgren, M.A.; Yaguchi, E.M.; Nelson, D.M.; Marshall, J.S.

    1974-01-01

    A survey was made of four groups of biota in the vicinity of the Big Rock Point Nuclear Plant near Charlevoix, Michigan, to determine their usefulness in locating possible sources of plutonium and other radionuclides to Lake Michigan. This 70 MW boiling-water reactor, located on the Lake Michigan shoreline, was chosen because its fuel contains recycled plutonium, and because it routinely discharges very low-level radioactive wastes into the lake. Samples of crayfish (Orconectes sp.), green algae (Chara sp. and Cladophora sp.), and an aquatic macrophyte (Potamogeton sp.) were collected in August 1973, at varying distances from the discharge and analyzed for 239 240 Pu, 90 Sr, and five gamma-emitting radionuclides. Comparison samples of reactor waste solution have also been analyzed for these radionuclides. Comparisons of the spatial distributions of the extremely low radionuclide concentrations in biota clearly indicated that 137 Cs, 134 Cs, 65 Zn, and 60 Co were released from the reactor; their concentrations decreased exponentially with increasing distance from the discharge. Conversely, concentrations of 239 240 Pu, 95 Zr, and 90 Sr showed no correlation with distance, suggesting any input from Big Rock was insignificant with respect to the atmospheric origin of these isotopes. The significance of these results is discussed, particularly with respect to current public debate over the possibility of local environmental hazards associated with the use of plutonium as a nuclear fuel. (U.S.)

  18. Microspectrophotometric and electrophysiological measurements of the visual pigment reaction in Astacus

    Energy Technology Data Exchange (ETDEWEB)

    Gaube, H.; Gerhards-Doett, C.; Schlecht, P.; Stieve, H.; Wilms, M.

    1981-07-01

    Microspectrophotometric measurements of the spectral absorption of single rhabdoms of Astacus leptodactylus were carried out under various conditions of light adaptation and at different pH. The results were compared with electrophysiological measurements in Astacus leptodactylus and two other crayfish species (Astacus fluviatilis and Procambarus (ortmannicus) acutus), obtained with selective adaptation by colored light. A bistable visual pigment system was found in the microspectrophotometric measurements. The absorption spectra for rhodopsin (..gamma../sub max/ ca. 553 nm), and metarhodopsin (..gamma../sub max/ ca. 495 nm) were calculated, on the basis of Ebrey-Honig nomograms, from typical difference spectra. In the electrophysiological measurements the maximal spectral sensitivity was recorded at 565 nm. No indication for a basic metarhodopsin could be found in the pH range from 4.5 to 10.5. After 2% glutaraldehyde treatment the bleaching product of rhodopsin was no longer photoreversible, probably due to decomposition of metarhodopsin into retinal and opsin. Our results do not indicate two different types of photoreceptor pigments in Astacus as have been demonstrated by Wald (1968) for Orconectes and Procambarus.

  19. Reproductive plasticity in freshwater invader: from long-term sperm storage to parthenogenesis.

    Science.gov (United States)

    Buřič, Miloš; Kouba, Antonín; Kozák, Pavel

    2013-01-01

    Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring) in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating) on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems.

  20. Reproductive plasticity in freshwater invader: from long-term sperm storage to parthenogenesis.

    Directory of Open Access Journals (Sweden)

    Miloš Buřič

    Full Text Available Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems.

  1. Reproductive Plasticity in Freshwater Invader: From Long-Term Sperm Storage to Parthenogenesis

    Science.gov (United States)

    Buřič, Miloš; Kouba, Antonín; Kozák, Pavel

    2013-01-01

    Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring) in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating) on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems. PMID:24204886

  2. Functional analysis of a mutated analogue of the crustacean hyperglycaemic hormone from the crayfish Pontastacus leptodactylus.

    Science.gov (United States)

    Mosco, Alessandro; Zlatev, Ventsislav; Guarnaccia, Corrado; Giulianini, Piero G

    2015-02-01

    The crustacean hyperglycaemic hormone (CHH), a pleiotropic neuropeptide, belongs to a family of structurally related peptides, having six cysteine residues in conserved positions forming three disulphide bridges, and regulating several physiological processes in crustaceans and insects. Structure-activity studies have shown that amidation of the C-terminus is important to confer biological activity to CHH. In this study we investigated the function of the d-Phe(3) of the N-terminal motif of Pontastacus leptodactylus CHH by a mutational analysis. The d-Phe in position 3 was substituted by a d-Ala and the functionality of the mutated analogue (Glp-d-A-CHH) was tested by in vivo biological assays. The mutated analogue resulted far less active than its wild-type counterparts, either in d- (Glp-d-CHH) or l- (Glp-l-CHH) configuration. These results suggest that Phe(3) is essential for the biological activity of P. leptodactylus CHH, demonstrating that also the N-terminus is involved in the binding with the receptor, and identifying in the Phe(3) a hot spot for the peptide-receptor binding. © 2015 Wiley Periodicals, Inc.

  3. Multiple drivers of decline in the global status of freshwater crayfish (Decapoda:Astacidea)

    Science.gov (United States)

    Nadia I. Richman; Monika Böhm; Susan B. Adams; Fernando Alvarez; Elizabeth A. Bergey; John J. S. Bunn; Quinton Burnham; Jay Cordeiro; Jason Coughran; Keith A. Crandall; Kathryn L. Dawkins; Robert J. DiStefano; Niall E. Doran; Lennart Edsman; Arnold G. Eversole; Leopold Füreder; James M. Furse; Francesca Gherardi; Premek Hamr; David M. Holdich; Pierre Horwitz; Kerrylyn Johnston; Clive M. Jones; Julia P. G. Jones; Robert L. Jones; Thomas G. Jones; Tadashi Kawai; Susan Lawler; Marilu López-Mejía; Rebecca M. Miller; Carlos Pedraza-Lara; Julian D. Reynolds; Alastair M. M. Richardson; Mark B. Schultz; Guenter A. Schuster; Peter J. Sibley; Catherine Souty-Grosset; Christopher A. Taylor; Roger F. Thoma; Jerry Walls; Todd S. Walsh; Ben Cohen

    2015-01-01

    Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world’s 590...

  4. Depressing effect of caffeine at crayfish neuromuscular synapses II. Initial search for possible sites of action.

    Science.gov (United States)

    Celenza, Kathryn M; Shugert, Elizabeth; Vélez, Samuel J

    2007-05-01

    Caffeine's unexpected depression of synaptic transmission in the superficial flexor muscle system (SFM) of Procambarus clarkii was studied by looking at three known sites of action of this drug: via adenosine and ryanodine receptors and inhibition of phosphodiesterase.1. JPs did not change in size when exposed to physiological concentrations of adenosine, suggesting that the SFM system lacks presynaptic adenosine receptors.2. JPs slightly increased in size in the presence of a phosphodiesterase inhibitor, the opposite response to that obtained with caffeine, suggesting that caffeine is not acting via this pathway.3. A calcium ionophore immediately enhanced synaptic transmission in the SFM system but when given in combination with caffeine the enhancement is reduced and declines over time.4. Serotonin enhanced synaptic transmission in the SFM system, but when given in combination with caffeine this enhancement was not observed.5. These caffeine effects are interpreted in terms of alterations to the calcium homeostatic mechanisms of the terminals.

  5. Investigating Issues in the Laboratory: The Behavior of Red Swamp Crayfish as an Invasive Species

    Science.gov (United States)

    Hewitt, Krissi M.; Kayes, Lori J.; Hubert, David; Chouinard, Adam

    2014-01-01

    Recent reform initiatives in undergraduate biology call for curricula that prepare students for dealing with real-world issues and making important links between science and society. In response to this call, we have developed an issues-based laboratory module that uses guided inquiry to integrate the concepts of animal behavior and population…

  6. Predictions of marbled crayfish establishment in conurbations fulfilled: Evidences form the Czech republic

    Czech Academy of Sciences Publication Activity Database

    Patoka, J.; Buřič, M.; Kolář, Vojtěch; Bláha, M.; Petrtýl, M.; Franta, P.; Tropek, Robert; Kalous, L.; Petrusek, A.; Kouba, A.

    2016-01-01

    Roč. 71, č. 12 (2016), s. 1380-1385 ISSN 0006-3088 R&D Projects: GA ČR GAP504/12/2525 Grant - others:GA JU(CZ) 158/2016/P; GA MŠk(CZ) LO1205 Institutional support: RVO:60077344 Keywords : Procambarus fallax f. virginalis * biological invasion * first record Subject RIV: EH - Ecology, Behaviour Impact factor: 0.759, year: 2016

  7. The relationships between length-weight, and meat content of freshwater crayfish (Astacus leptodactylus

    Directory of Open Access Journals (Sweden)

    Ebru Yılmaz

    2015-12-01

    Full Text Available Bu çalışmada Gaga Gölü’nden yakalanan tatlısu ıstakozu (Astacus leptodactylus’nun ağırlık-uzunluk ilişkisi ve et verimi incelendi. Aynı karapaks uzunluk grubundaki erkek ve dişi tatlısu ıstakozlarının (kerevit karapaks genişliği, abdomen uzunluğu, abdomen genişliği, toplam uzunluğu, kıskaç uzunluğu, kıskaç genişliği ve kıskaç ayak uzunluğu karşılaştırıldığında erkeklerin dişilerden istatistiksel olarak önemli derecede uzun olduğu belirlendi (P

  8. Effect of copper exposure on histamine concentrations in the marbled crayfish (Procambarus fallax forma virginalis).

    NARCIS (Netherlands)

    Soedarini, B.; Klaver, L.; Giesen, D.; Roessink, I.; Widianarko, B.; van Straalen, N.M.; van Gestel, C.A.M.

    2013-01-01

    Crustaceans can store excess copper in the hepatopancreas, an organ playing a role in digestive activity as well as in neurosecretory control. Here, we studied the effect of copper exposure on the level of histamine, an indicator of food spoilage in edible crustaceans. Histamine is also a

  9. Effect of copper exposure on histamine concentrations in the marbled crayfish

    NARCIS (Netherlands)

    Soedarini, B.; Klaver, L.; Giesen, D.; Roessink, I.; Widianarko, B.; Straalen, van N.M.; Gestel, van C.A.M.

    2013-01-01

    Crustaceans can store excess copper in the hepatopancreas, an organ playing a role in digestive activity as well as in neurosecretory control. Here, we studied the effect of copper exposure on the level of histamine, an indicator of food spoilage in edibl

  10. Founder event and its effect on genetic variation in translocated populations of noble crayfish (Astacus astacus)

    Czech Academy of Sciences Publication Activity Database

    Bláha, M.; Žurovcová, Martina; Kouba, A.; Policar, T.; Kozák, P.

    2016-01-01

    Roč. 57, č. 1 (2016), s. 99-106 ISSN 1234-1983 Grant - others:European Fund(CZ) CZ.1.07/2.3.00/30.0049; European Fund(CZ) CZ1.05/2.1.00/01.0024; GA ČR(CZ) GAP505/12/0545 Institutional support: RVO:60077344 Keywords : bottleneck * conservation * homozygote excess Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.655, year: 2016 http://link.springer.com/article/10.1007%2Fs13353-015-0296-3

  11. Effects of the Palisades Nuclear Power Plant on Lake Michigan

    International Nuclear Information System (INIS)

    Benda, R.S.; Gulvas, J.

    1976-01-01

    An 18-month study (May 1972 to October 1973) was undertaken to determine the effects of once-through cooling water from the Palisades nuclear power plant on the biota of Lake Michigan. The Palisades facility [821 Mw(e)] began operations in early 1972. The cooling-water intake is submerged 1006 m offshore at a minimum depth of about 7.6 m. The heated discharge enters the lake directly at the shoreline. In the original once-through cooling system of the plant, the total flow rate was about 30,686 liters/sec, with a maximum ΔT of 13.9 0 C. The size range of 36 surface plumes was 6.9 to 352.1 ha, with an average size of 93.7 ha at the 1.7 0 C isotherm. From May 16, 1972, to Oct. 25, 1973, a total of 651,712 fish weighing 19,842.2 kg were impinged on the traveling screens. Alewife (Alosa pseudoharengus), slimy sculpin (Cottus cognathus), spottail shiner (Notropis hudsonius), and yellow perch (Perca flavescens) made up 58.6, 27.5, 7.2, and 4.4 percent, respectively, of the total number. Coregonids and salmonids and smelt (Osmerus mordax) made up 0.2 and 1.0 percent of the total, respectively. The fish appeared seasonally on the screens, with none of the 37 recorded species being collected regularly. In addition, 4768 crayfish (Orconectes propinquis) were counted, mostly during late spring and early summer. No significant change in the abundance of prominent species in lake populations occurred after the introduction of the thermal discharge, but the spawning period for one-third of the yellow perch collected was advanced by approximately 3 weeks in 1973

  12. Subcellular localisation of radionuclides by transmission electronic microscopy in aquatic and terrestrial organisms

    International Nuclear Information System (INIS)

    Floriani, M.; Grasset, G.; Simon, O.; Morlon, H.; Laroche, L.

    2004-01-01

    The global framework of this study is to go further in the understanding of the involved mechanisms of uranium and selenium internalisation at the subcellular level and of their toxicity towards several aquatic and terrestrial organisms. In this context, the applications and performances of a Scanning Transmission Electron Microscope (TEM/STEM) equipped with CCD camera and Energy-Dispersive- X-Ray (EDAX) analysis are reported. The principal merit of this equipment is the clear expression of element distribution with nanometer resolution. The sample for TEM analysis were prepared in ultrathin sections of 70-140 nm (thickness) and those for EDAX in sections of 200-500 nm. This method offers the possibility of a direct correlation between histological image and distribution map of trace elements. For each sample, following TEM analysis, EDAX spectra or EDAX mapping were also recorded to confirm the identity of the electron dense material in the scanned sections. Demonstration of the usefulness of this method to understand the bioaccumulation mechanisms and to study the effect of the pollutant uptake at the subcellular level was performed for target organs of a metal (U) and a metalloid (Se) in various biological models: a higher rooted plant (Phaseolus vulgaris)) and a freshwater invertebrate (Orconectes Limosus) and a unicellular green alga (Chlamydomonas reinhardtii)). TEM-EDAX analysis revealed the presence of U-deposits in gills and digestive gland in crayfish, and in vacuoles or in the cytoplasm of different rooted cells bean. In the alga, the accumulation of Se was found in electron-dense granules within cytoplasm associated with ultrastructural changes and starch accumulation. (author)

  13. CRAYFISHERIES IN FINLAND, A SHORT OVERVIEW

    Directory of Open Access Journals (Sweden)

    JUSSILA J.

    2004-01-01

    Full Text Available Crayfish trapping and activities related to crayfishing have traditionally been lucrative businesses in rural Finland. The catch itself, varying in the 1990’s from 2 to 4 millions crayfish annually, is worth 4 to 8 millions euros. Crayfishing has been a crucial part of small-scale business farms with access to productive crayfish stocks. The catch has so far been mainly noble crayfish (Astacus astacus but stockings with signal crayfish (Pacifastacus leniusculus during the past 15 years have started to produce commercial scale catches in Southern Finland. This has had a strong impact on commercial markets and has encouraged stocking of signal crayfish to an increasing number of water bodies, both legally and illegally. Noble crayfish stocks, on the other hand, have suffered from crayfish plague (Aphanomyces astaci and watercourse construction. Up to 10 commercially productive noble crayfish stocks have been infected with crayfish plague annually. Most of the signal crayfish stocks have been infected as well, with the price being paid in loss of commercial value and even population collapse. The traditional way to catch crayfish is trapping during the crayfish season, with an increasing number of crayfish farmers competing for the same markets. Crayfish tourism is also taking its first steps, with a lot of opportunities for services targeted at urban upper class customers both in domestic and foreign markets. The future of Finnish crayfisheries remains uncertain at the moment with the following processes under way: spread of signal crayfish northwards, spread of crayfish plague, declining noble crayfish catch, restructuring of the commercial crayfish markets into several fractions, increasing demand for noble crayfish stockings, increasing demand for market size noble crayfish and demand for processed crayfish.

  14. A novel genus and cryptic species harboured within the monotypic freshwater crayfish genus Tenuibranchiurus Riek, 1951 (Decapoda: Parastacidae

    Directory of Open Access Journals (Sweden)

    Kathryn L. Dawkins

    2017-05-01

    Full Text Available Identifying species groups is an important yet difficult task, with there being no single accepted definition as to what constitutes a species, nor a set of criteria by which they should be delineated. Employing the General Lineage Concept somewhat circumvents these issues, as this concept allows multiple concordant lines of evidence to be used as support for species delimitation, where a species is defined as any independently evolving lineage. Genetically diverse groups have previously been identified within the monotypic parastacid genus Tenuibranchiurus Riek, 1951, but no further investigation of this diversity has previously been undertaken. Analysis of two mitochondrial DNA gene regions has previously identified two highly divergent groups within this taxon, representing populations from Queensland (Qld and New South Wales (NSW, respectively. Additional testing within this study of both mitochondrial and nuclear DNA through species discovery analyses identified genetically diverse groups within these regions, which were further supported by lineage validation methods. The degree of genetic differentiation between Qld and NSW populations supports the recognition of two genera; with Qld retaining the original genus name Tenuibranchiurus, and NSW designated as Gen. nov. until a formal description is completed. Concordance between the species discovery and lineage validation methods supports the presence of six species within Tenuibranchiurus and two within Gen. nov. The recognition of additional species removes the monotypy of the genus, and the methods used can improve species identification within groups of organisms with taxonomic problems and cryptic diversity.

  15. Sperm traits negatively covary with size and asymmetry of a secondary sexual trait in a freshwater crayfish

    OpenAIRE

    Galeotti, P.; Bernini, G.; Locatello, L.; Sacchi, R.; Fasola, M.; Rubolini, D.

    2012-01-01

    In species where females mate promiscuously, the reproductive success of males depends both on their ability to acquire mates (pre-copulatory sexual selection) and ability of their ejaculates to outcompete those of other males (post-copulatory sexual selection). Sperm competition theory predicts a negative relationship between investment in body traits favouring mate acquisition (secondary sexual characters, SSCs) and investment in ejaculate size or quality, due to the inherent costs of sperm...

  16. {sup 226}Ra concentrations in crayfish tissues, water, and sediments from the Serpent River Basin in Northeastern Ontario, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Alikhan, M.A. [Laurentian Univ., Sudbury, ON (Canada). Dept of Biology

    1996-12-31

    Lower Serpent River, as well as Elliot, McCarthy and McCabe lakes had highest {sup 226}Ra contamination, Chrisman, Quirke and Whiskey lakes a moderate one, Flack and Semiwhite lakes and the `distant` control, Lake Wanapitei, the lowest. {sup 226}Ra activity in Cambarus robustus tissues was directly related to their background levels. Thus, concentration coefficient (tissue/sediment concentrations) for {sup 226}Ra ranged from 0.53 to 0.74 in highly contaminated Elliot and McCarthy lakes, 0.28 to 0.59 in moderately contaminated Quirke and Whiskey lakes, and from 0.27 to 3.44 in least contaminated Semiwhite and Flack lakes. Among various organs analysed, exoskeleton showed the highest (43.04 - 90.69%) and the tail muscles the lowest (2.95 -17.14%) {sup 226}Ra activity. {sup 226}Ra concentrations in the alimentary canal were considered a part of the ambient environment as they had not been absorbed. 12 refs, 1 fig, 1 tab.

  17. Determination of chromium in treated crayfish, Procambarus clarkii, by electrothermal ASS: study of chromium accumulation in different tissues

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, F.; Diaz, J.; Medina, J.; Del Ramo, J.; Pastor, A.

    1986-06-01

    In the present study, the authors investigated the accumulation of chromium in muscle, hepatopancreas, antennal glands, and gills of Procambarus clarkii (Girard) from Lake Albufera following Cr(VI)-exposure. Determinations of chromium were made by using Electrothermal Atomic Absorption Spectroscopy and the standard additions method.

  18. Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids.

    Science.gov (United States)

    Miles, Jesse C; Hua, Jessica; Sepulveda, Maria S; Krupke, Christian H; Hoverman, Jason T

    2017-01-01

    The widespread usage of neonicotinoid insecticides has sparked concern over their effects on non-target organisms. While research has largely focused on terrestrial systems, the low soil binding and high water solubility of neonicotinoids, paired with their extensive use on the landscape, puts aquatic environments at high risk for contamination via runoff events. We assessed the potential threat of these compounds to wetland communities using a combination of field surveys and experimental exposures including concentrations that are representative of what invertebrates experience in the field. In laboratory toxicity experiments, LC50 values ranged from 0.002 ppm to 1.2 ppm for aquatic invertebrates exposed to clothianidin. However, freshwater snails and amphibian larvae showed high tolerance to the chemical with no mortality observed at the highest dissolvable concentration of the insecticide. We also observed behavioral effects of clothianidin. Water bugs, Belostoma flumineum, displayed a dose-dependent reduction in feeding rate following exposure to clothianidin. Similarly, crayfish, Orconectes propinquus, exhibited reduced responsiveness to stimulus with increasing clothianidin concentration. Using a semi-natural mesocosm experiment, we manipulated clothianidin concentration (0.6, 5, and 352 ppb) and the presence of predatory invertebrates to explore community-level effects. We observed high invertebrate predator mortality with increases in clothianidin concentration. With increased predator mortality, prey survival increased by 50% at the highest clothianidin concentration. Thus, clothianidin contamination can result in a top-down trophic cascade in a community dominated by invertebrate predators. In our Indiana field study, we detected clothianidin (max = 176 ppb), imidacloprid (max = 141 ppb), and acetamiprid (max = 7 ppb) in soil samples. In water samples, we detected clothianidin (max = 0.67 ppb), imidacloprid (max = 0.18 ppb), and thiamethoxam (max = 2

  19. Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids.

    Directory of Open Access Journals (Sweden)

    Jesse C Miles

    Full Text Available The widespread usage of neonicotinoid insecticides has sparked concern over their effects on non-target organisms. While research has largely focused on terrestrial systems, the low soil binding and high water solubility of neonicotinoids, paired with their extensive use on the landscape, puts aquatic environments at high risk for contamination via runoff events. We assessed the potential threat of these compounds to wetland communities using a combination of field surveys and experimental exposures including concentrations that are representative of what invertebrates experience in the field. In laboratory toxicity experiments, LC50 values ranged from 0.002 ppm to 1.2 ppm for aquatic invertebrates exposed to clothianidin. However, freshwater snails and amphibian larvae showed high tolerance to the chemical with no mortality observed at the highest dissolvable concentration of the insecticide. We also observed behavioral effects of clothianidin. Water bugs, Belostoma flumineum, displayed a dose-dependent reduction in feeding rate following exposure to clothianidin. Similarly, crayfish, Orconectes propinquus, exhibited reduced responsiveness to stimulus with increasing clothianidin concentration. Using a semi-natural mesocosm experiment, we manipulated clothianidin concentration (0.6, 5, and 352 ppb and the presence of predatory invertebrates to explore community-level effects. We observed high invertebrate predator mortality with increases in clothianidin concentration. With increased predator mortality, prey survival increased by 50% at the highest clothianidin concentration. Thus, clothianidin contamination can result in a top-down trophic cascade in a community dominated by invertebrate predators. In our Indiana field study, we detected clothianidin (max = 176 ppb, imidacloprid (max = 141 ppb, and acetamiprid (max = 7 ppb in soil samples. In water samples, we detected clothianidin (max = 0.67 ppb, imidacloprid (max = 0.18 ppb, and

  20. Neuropeptide Signaling in Crustaceans Probed by Mass Spectrometry

    Science.gov (United States)

    Liang, Zhidan

    Neuropeptides are one of the most diverse classes of signaling molecules whose identities and functions are not yet fully understood. They have been implicated in the regulation of a wide range of physiological processes, including feeding-related and motivated behaviors, and also environmental adaptations. In this work, improved mass spectrometry-based analytical platforms were developed and applied to the crustacean systems to characterize signaling molecules. This dissertation begins with a review of mass spectrometry-based neuropeptide studies from both temporal- and spatial-domains. This review is then followed by several chapters detailing a few research projects related to the crustacean neuropeptidomic characterization and comparative analysis. The neuropeptidome of crayfish, Orconectes rusticus is characterized for the first time using mass spectrometry-based tools. In vivo microdialysis sampling technique offers the capability of direct sampling from extracellular space in a time-resolved manner. It is used to investigate the secreted neuropeptide and neurotransmitter content in Jonah crab, Cancer borealis, in this work. A new quantitation strategy using alternative mass spectrometry data acquisition approach is developed and applied for the first time to quantify neuropeptides. Coupling of this method with microdialysis enables the study of neuropeptide dynamics concurrent with different behaviors. Proof-of-principle experiments validating this approach have been carried out in Jonah crab, Cancer borealis to study feeding- and circadian rhythm-related neuropeptide changes using micoridialysis in a time-resolved manner. This permits a close correlation between behavioral and neurochemical changes, providing potential candidates for future validation of regulatory roles. In addition to providing spatial information, mass spectrometry imaging (MSI) technique enables the characterization of signaling molecules while preserving the temporal resolution. A

  1. Silencing two main isoforms of crustacean hyperglycemic hormone (CHH) induces compensatory expression of two CHH-like transcripts in the red swamp crayfish Procambarus clarkii

    OpenAIRE

    Manfrin, C; Peruzza, L; Bonzi, Lc; Pallavicini, A; Giulianini, Pg

    2015-01-01

    RNA interference has frequently been applied to modulate gene function in organisms. With the aim of creating new autocidal methods based on neuro-endocrine disruptors for invasive populations of Procambarus clarkii, we silenced the Crustacean Hyperglycemic Hormone (CHH) by injecting the corresponding dsRNA. CHH is a pleiotropic hormone that primarily regulates the mobilization of energy reserves and plays a pivotal role in stress responses. Here, we describe two experiments aimed at testing ...

  2. Cherax snowden, a new species of crayfish (Crustacea, Decapoda, Parastacidae) from the Kepala Burung (Vogelkop) Peninsula in Irian Jaya (West Papua), Indonesia.

    Science.gov (United States)

    Lukhaup, Christian; Panteleit, Jörn; Schrimpf, Anne

    2015-01-01

    A new species, Cherax snowden sp. n., from the Oinsok River Drainage, Sawiat District in the central part of the Kepala Burung (Vogelkop) Peninsula, West Papua, Indonesia, is described, figured and compared with the closest related species, Cherax holthuisi Lukhaup & Pekny, 2006. This species is collected and exported for ornamental purposes and its commercial name in the pet trade is "orange tip" or "green orange tip". Both species may be easily distinguished morphologically or by using sequence divergence, which is substantial, for considering Cherax snowden sp. n. to be a new species.

  3. Euastacus morgani sp. n., a new spiny crayfish (Crustacea, Decapoda, Parastacidae from the highland rainforests of eastern New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    Jason Coughran

    2011-03-01

    Full Text Available Euastacus morgani sp. n., is described from a highland, rainforest site in Bindarri National Park, in eastern New South Wales, Australia. Euastacus morgani is found living sympatrically with two more common species, E. dangadi Morgan, 1997 and E. neohirsutus Riek, 1956. Systematically, the species belongs in the ‘simplex’ complex of the genus that includes E. simplex Riek, 1956, E. clarkae Morgan, 1997, E. maccai McCormack and Coughran 2008 and E. morgani. This new species differs from its nearest congenor, E. simplex, inthree mesial carpal spines. A key to the ‘simplex’ complex is presented.

  4. An invaded invader: high prevalence of entocytherid ostracods on the red swamp crayfish Procambarus clarkii (Girard, 1852) in the Eastern Iberian Peninsula

    Czech Academy of Sciences Publication Activity Database

    Aguilar-Alberola, J. A.; Mesquita-Joanes, F.; López, S.; Mestre, A.; Casanova, J. C.; Rueda, J.; Ribas, Alexis

    2012-01-01

    Roč. 688, č. 1 (2012), s. 63-73 ISSN 0018-8158 Institutional research plan: CEZ:AV0Z60930519 Keywords : Ostracoda * Commensalism * Alien species * Biological invasion Subject RIV: EG - Zoology Impact factor: 1.985, year: 2012

  5. Protein modification in the post-mating spermatophore of the signal crayfish Pacifastacus leniusculus: insight into the tyrosine phosphorylation in a non-motile spermatozoon

    Czech Academy of Sciences Publication Activity Database

    Niksirat, H.; Vancová, Marie; Andersson, L.; James, P.; Kouba, A.; Kozák, P.

    2016-01-01

    Roč. 172, SEP (2016), s. 123-130 ISSN 0378-4320 R&D Projects: GA TA ČR(CZ) TE01020118 Institutional support: RVO:60077344 Keywords : microtubular radial arm * spermatozoon capacitation * tyrosine-phosphorylation * ultrastructural localization Subject RIV: EA - Cell Biology Impact factor: 1.605, year: 2016

  6. Using stable isotope analysis to determine the contribution of naturally occurring pond biota and supplementary feed to the diet of farmed Australian freshwater crayfish, redclaw (Cherax quadricarinatus

    Directory of Open Access Journals (Sweden)

    Melissa K. Joyce

    2015-12-01

    Full Text Available Abstract Nutritional requirements of redclaw (Cherax quadricarinatus farmed in Australia are poorly understood and little is known on what is actively being consumed in semi-intensive pond culture. In this study the isotopic signatures of δ13C and δ15N of potential food sources were analysed with a multi-source mixing model to determine the extent of their contribution to the diet of farmed redclaw. Four commercial redclaw farms in North Queensland, Australia (Mareeba, Biboorha, Wondecla and Topaz were sampled for naturally occurring pond organisms and commonly used supplemental feed such as raw corn, soybean, lupin, commercial redclaw, and chicken feed. Both naturally occurring pond biota and supplemental feed contribute to the tissue composition of redclaw to some degree. However, the contribution varies with the type of feed and availability of natural sources, for example plant material at Topaz Farm was a greater contributor with 43.9 ± 19.5 % compared to supplementary sources raw corn 8.20 ± 3.10 and lupin 1.60 ± 1.70 %. Moreover, some supplemental feeds provided a direct nutrient source for primary pond productivity; contribution of the redclaw pellet to zoo- and phytoplankton at Wondecla Farm was 83.1 ± 6.50 and 50.0 ± 9.50 %, respectively, with similarly high values for chicken feed at Biboorha Farm of 72.6 ± 4.70 and 83.4 ± 6.90 %. The cost effectiveness of such feeds needs to be questioned if these are not being consumed and utilised directly. Providing a species-specific formulated feed with improved water stability would enhance production reliability and facilitate growth within the industry.

  7. HABITAT PREFERENCE OF DIFFERENT SIZE CLASSES OF AUSTROPOTAMOBIUS PALLIPES IN AN IRISH RIVER

    Directory of Open Access Journals (Sweden)

    DEMERS A.

    2003-04-01

    Full Text Available Juvenile and immature crayfish are more difficult to find than adults and in consequence rather little is known about their habitat preferences. Smaller crayfish are able to inhabit different areas within the stream compared to adult crayfish. Whereas adult crayfish occur under stones and cobble in the river, juveniles and small individuals may be found along the margins, among rootlets and vegetation. A survey was carried at two sites in the Liffey catchment (Ireland to assess habitat preference of crayfish according to size. A Surber sampler was used to collect crayfish in five types of habitat present at these sites. Each site presented a different distribution of crayfish amongst the habitat types. At Kilbride bridge, crayfish preferred cobble to pebbles and submerged and emergent macrophytes, while at Carragh bridge, crayfish were more dispersed throughout the habitat types. At both sites, juveniles and one year old crayfish were found in a variety of habitat types, whereas adults were only found in cobble and pebbles. The discrepancy in crayfish densities between the two sites can probably be explained by characteristics, such as depth and flow rate, that were not taken into account in the categorisation of the habitats.

  8. Invertebrate medicine

    National Research Council Canada - National Science Library

    Lewbart, G.A

    2012-01-01

    .... Coverage includes sponges, jellyfish, anemones, corals, mollusks, starfish, sea urchins, crabs, crayfish, lobsters, shrimp, hermit crabs, spiders, scorpions, and many more, with chapters organized by taxonomy...

  9. Morphological convergence in a Mexican garter snake associated with the ingestion of a novel prey.

    Science.gov (United States)

    Manjarrez, Javier; Macías Garcia, Constantino; Drummond, Hugh

    2017-09-01

    Morphological convergence is expected when organisms which differ in phenotype experience similar functional demands, which lead to similar associations between resource utilization and performance. To consume prey with hard exoskeletons, snakes require either specialized head morphology, or to deal with them when they are vulnerable, for example, during molting. Such attributes may in turn reduce the efficiency with which they prey on soft-bodied, slippery animals such as fish. Snakes which consume a range of prey may present intermediate morphology, such as that of Thamnophiine (Natricinae), which may be classified morphometrically across the soft-hard prey dietary boundary. In this study, we compared the dentition and head structure of populations of Thamnophis melanogaster that have entered the arthropod-crustacean (crayfish)-eating niche and those that have not, and tested for convergence between the former and two distantly related crayfish specialists of the genus Regina ( R . septemvittata and R. grahamii ). As a control, we included the congener T. eques . Multivariate analysis of jaw length, head length, head width, and number of maxillary teeth yielded three significant canonical variables that together explained 98.8% of the variance in the size-corrected morphological data. The first canonical variable significantly discriminated between the three species. The results show that head dimensions and number of teeth of the two Regina species are more similar to those of crayfish-eating T. melanogaster than to non-crayfish-eating snakes or of T. eques . It is unclear how particular head proportions or teeth number facilitates capture of crayfish, but our results and the rarity of soft crayfish ingestion by T. melanogaster may reflect the novelty of this niche expansion, and are consistent with the hypothesis that some populations of T. melanogaster have converged in their head morphology with the two soft crayfish-eating Regina species, although we

  10. Aquatic macroinvertebrate responses to native and non-native predators

    Directory of Open Access Journals (Sweden)

    Haddaway N. R.

    2014-01-01

    Full Text Available Non-native species can profoundly affect native ecosystems through trophic interactions with native species. Native prey may respond differently to non-native versus native predators since they lack prior experience. Here we investigate antipredator responses of two common freshwater macroinvertebrates, Gammarus pulex and Potamopyrgus jenkinsi, to olfactory cues from three predators; sympatric native fish (Gasterosteus aculeatus, sympatric native crayfish (Austropotamobius pallipes, and novel invasive crayfish (Pacifastacus leniusculus. G. pulex responded differently to fish and crayfish; showing enhanced locomotion in response to fish, but a preference for the dark over the light in response to the crayfish. P.jenkinsi showed increased vertical migration in response to all three predator cues relative to controls. These different responses to fish and crayfish are hypothesised to reflect the predators’ differing predation types; benthic for crayfish and pelagic for fish. However, we found no difference in response to native versus invasive crayfish, indicating that prey naiveté is unlikely to drive the impacts of invasive crayfish. The Predator Recognition Continuum Hypothesis proposes that benefits of generalisable predator recognition outweigh costs when predators are diverse. Generalised responses of prey as observed here will be adaptive in the presence of an invader, and may reduce novel predators’ potential impacts.

  11. ROUNDTABLE - SESSION 2 EXPLOITATION, CONSERVATION AND LEGISLATION

    Directory of Open Access Journals (Sweden)

    EDSMAN L.

    2004-01-01

    Full Text Available The link between socioeconomics and conservation and the role of legislation in conservation work was discussed in the group with participants from nine European countries. Interest and knowledge among the general public, stakeholders and managers is the key to successful conservation of native crayfish species. Exploitation and conservation do not necessarily exclude each other. A controlled fishery, where it can be sustained, may be an essential tool for conservation by increasing the general awareness and involving more people in the task of protecting the native crayfish species. This strategy is mainly possible for the noble crayfish in the northern part of its distribution, where strong traditions connected to crayfish also exist. A balance between utilisation and overexploitation has to be found and local guidelines for sustainable exploitation produced. Media, the Internet and educational material aimed at schools and stakeholders are excellent ways of reaching a wide audience with information. Universal objectives, rules and regulations at the European level are desirable and the noble crayfish and the stone crayfish should be included in Annex II of the Habitat Directive. Based on this framework detailed regulations are best worked out at the national level, considering the specific crayfish situation in the country. Information about the legislation, the purpose of the legislation and the consequences when not obeying it should be distributed. Stricter regulation of the trade with live alien crayfish is vital because of the associated risk of introducing new diseases and species.

  12. Neuroendocrine responses of a crustacean host to viral infection: effects of infection of white spot syndrome virus on the expression and release of crustacean hyperglycemic hormone in the crayfish Procambarus clarkii.

    Science.gov (United States)

    Lin, Ling-Jiun; Chen, Yan-Jhou; Chang, Yun-Shiang; Lee, Chi-Ying

    2013-02-01

    The objectives of the present study were to characterize the changes in crustacean hyperglycemic hormone (CHH) transcript and peptide levels in response to infection of white spot syndrome virus (WSSV) in a crustacean, Procambarus clarkii. After viral challenge, significant increase in virus load began at 24 h post injection (hpi) and the increase was much more substantial at 48 and 72 hpi. The hemolymph CHH levels rapidly increased after viral challenge; the increase started as early as 3 hpi and lasted for at least 2 d after the challenge. In contrast, the hemolymph glucose levels did not significantly changed over a 2 d period in the WSSV-infected animals. The CHH transcript and peptide levels in tissues were also determined. The CHH transcript levels in the eyestalk ganglia (the major site of CHH synthesis) of the virus-infected animals did not significantly change over a 2 d period and those in 2 extra-eyestalk tissues (the thoracic ganglia and cerebral ganglia) significantly increased at 24 and 48 hpi. The CHH peptide levels in the eyestalk ganglia of the virus-infected animals significantly decreased at 24 and 48 hpi and those in the thoracic ganglia and cerebral ganglia remained unchanged over a 2 d period. These data demonstrated a WSSV-induced increase in the release of CHH into hemolymph that is rapid in onset and lasting in duration. Changes in the CHH transcript and peptide levels implied that the WSSV-induced increase in hemolymph CHH levels primarily resulted from an enhanced release from the eyestalk ganglia, but the contribution of the 2 extra-eyestalk tissues to hemolymph pool of CHH increased as viral infection progressed. The combined patterns of change in the hemolymph glucose and CHH levels further suggest that the virus-enhanced CHH release would lead to higher glycolytic activity and elevated glucose mobilization presumably favorable for viral replication. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. AN INVESTIGATION INTO THE DISAPPEARANCE OF AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET POPULATIONS IN THE HEADWATERS OF THE NORE RIVER, IRELAND AND THE CORRELATION TO WATER QUALITY

    Directory of Open Access Journals (Sweden)

    LYONS R.

    2003-04-01

    Full Text Available Monitoring of the protected white-clawed crayfish Austropotamobius pallipes (Lereboullet has been carried out in the headwaters of the Nore River since 1995. In recent years a reduction in crayfish abundance had become apparent. Some populations had completely disappeared. Adult crayfish were sampled using the baited trap method while juveniles were sampled using a modified surber sampler. The temporal variation in baited trap data was found to be significant at three of the sites while significant variation in enclosure sampling data was found at two sites. In an effort to ascertain why the populations had disappeared a possible relationship between water quality and adult and juvenile crayfish numbers was investigated. Water quality was assessed using both chemical and macroinvertebrate data. Macroinvertebrate sampling revealed deterioration in water quality at all sites. Results also showed the disappearance of crayfish from both Q3 and Q3-4 waters at some sites yet crayfish remain at these Q-ratings at other sites. Therefore the Q-rating below which crayfish cannot survive cannot clearly be defined. However, no clear correlation was observed between the water chemistry data and the crayfish data. Crayfish populations at the Fertagh (FRT site appear to be surviving intermittent pollution and eutrophic conditions where pre-dawn oxygen sags reach lows of 4.4 mg/l O2. Deterioration in water quality as indicated by the Q-value biotic index coincided with reduced crayfish catches. There is no evidence to suggest that predation be it of aquatic or terrestrial origin is a major contributing factor.

  14. 75 FR 42040 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition to List the...

    Science.gov (United States)

    2010-07-20

    ... toads are found along the river corridor where perennial water occurs and bullfrogs (Lithobates (=Rana) catesbeiana) and crayfish (Procambarus sp.) are few or absent. In a typical year, tens or hundreds of...

  15. STATUS OF AUSTROPOTAMOBIUS PALLIPES COMPLEX IN THE WATERCOURSES OF THE ALESSANDRIA PROVINCE (N-W ITALY

    Directory of Open Access Journals (Sweden)

    NARDI P. A.

    2005-07-01

    Full Text Available Information was gathered on the distribution of white-clawed crayfish Austropotamobius pallipes complex in the watercourses of the Alessandria province (NW Italy, on the biological and ecological preferences of the species, and on the features of the biotopes in which it is found. A total of 409 sites on 361 watercourses connected to the main sub-basins of the Po River were analysed, with data gathered during the field research phase, conducted for three consecutive summers from 2002 through 2004. Thirteen percent of the sites investigated were found to currently house crayfish populations. The persistence in time of superficial water and natural morphology of the watercourse were found to be the chief requirements for the presence of crayfish. Data on land use, human density and other factors which potentially limit the survival of crayfish populations were also analysed.

  16. Critters in the Classroom.

    Science.gov (United States)

    Smith, Robert W.; Fleisher, Paul

    1984-01-01

    The use of invertebrates as classroom "pets" can develop students' skills in scientific inquiry and instill respect for science. Few materials are needed for projects involving invertebrates. Suggested activities using snails, crickets, earthworms, crayfish, and guppies are offered. (DF)

  17. Trophic transfer of aluminium through an aquatic grazer-omnivore food chain

    International Nuclear Information System (INIS)

    Walton, Rachel C.; McCrohan, Catherine R.; Livens, Francis; White, Keith N.

    2010-01-01

    The potential for trophic transfer of aluminium (Al) was investigated using a grazing detritivore, the freshwater snail Lymnaea stagnalis, and a predator, the signal crayfish Pacifastacus leniusculus. Snails were exposed to either aqueous Al (500 μg l -1 ) in the presence or absence of an inorganic ligand (phosphate (+P); 500 μg l -1 ) for 30 days, or kept as unexposed controls. Subcellular partitioning of Al in the snail tissues was characterised using ultracentrifugation. Al content in the soft tissues and the subcellular fractions was measured using inductively coupled plasma atomic emission spectroscopy. Exposed and control snails were fed to individually housed crayfish (n = 6 per group) over 40 days. Water samples, uneaten snail tissue and faeces were collected throughout the experiment in order to assess the fate of Al. Behavioural toxicity to the crayfish was assessed at four time points, and tissue accumulation of Al in soft tissues was measured following a 2-day depuration period. Snails exposed to Al + P accumulated more Al per snail than those exposed to Al only (291 μg vs 206 μg), and also contained a higher proportion of detoxified Al (in inorganic granules and associated with heat stable proteins) (39% vs 26%). There were no significant differences in behavioural activity between the different groups of crayfish at any time point. Crayfish fed snails exposed to only Al accumulated significant levels of Al in their total soft tissues, compared to controls; crayfish fed Al + P-exposed snails did not, even though concentrations of Al in these snails were higher. The highest concentrations of Al were found in the green gland in both crayfish feeding groups, and the gut and hepatopancreas in crayfish fed Al only exposed snails; all of these were significantly higher than in crayfish fed control snails. There was no significant accumulation of Al in the gills or flexor muscle in any group. At least 17% of trophically available Al in the snail tissues

  18. Trophic transfer of aluminium through an aquatic grazer-omnivore food chain.

    Science.gov (United States)

    Walton, Rachel C; McCrohan, Catherine R; Livens, Francis; White, Keith N

    2010-08-01

    The potential for trophic transfer of aluminium (Al) was investigated using a grazing detritivore, the freshwater snail Lymnaea stagnalis, and a predator, the signal crayfish Pacifastacus leniusculus. Snails were exposed to either aqueous Al (500 microg l(-1)) in the presence or absence of an inorganic ligand (phosphate (+P); 500 microg l(-1)) for 30 days, or kept as unexposed controls. Subcellular partitioning of Al in the snail tissues was characterised using ultracentrifugation. Al content in the soft tissues and the subcellular fractions was measured using inductively coupled plasma atomic emission spectroscopy. Exposed and control snails were fed to individually housed crayfish (n=6 per group) over 40 days. Water samples, uneaten snail tissue and faeces were collected throughout the experiment in order to assess the fate of Al. Behavioural toxicity to the crayfish was assessed at four time points, and tissue accumulation of Al in soft tissues was measured following a 2-day depuration period. Snails exposed to Al+P accumulated more Al per snail than those exposed to Al only (291 microg vs 206 microg), and also contained a higher proportion of detoxified Al (in inorganic granules and associated with heat stable proteins) (39% vs 26%). There were no significant differences in behavioural activity between the different groups of crayfish at any time point. Crayfish fed snails exposed to only Al accumulated significant levels of Al in their total soft tissues, compared to controls; crayfish fed Al+P-exposed snails did not, even though concentrations of Al in these snails were higher. The highest concentrations of Al were found in the green gland in both crayfish feeding groups, and the gut and hepatopancreas in crayfish fed Al only exposed snails; all of these were significantly higher than in crayfish fed control snails. There was no significant accumulation of Al in the gills or flexor muscle in any group. At least 17% of trophically available Al in the snail

  19. Trophic transfer of aluminium through an aquatic grazer-omnivore food chain

    Energy Technology Data Exchange (ETDEWEB)

    Walton, Rachel C., E-mail: Rachel.C.Walton@manchester.ac.uk [Faculty of Life Sciences, University of Manchester, Manchester M13 9PT (United Kingdom); McCrohan, Catherine R., E-mail: cathy.mccrohan@manchester.ac.uk [Faculty of Life Sciences, University of Manchester, Manchester M13 9PT (United Kingdom); Livens, Francis, E-mail: francis.livens@manchester.ac.uk [Schools of Earth, Atmospheric and Environmental Science and of Chemistry, University of Manchester, Manchester M13 9PL (United Kingdom); White, Keith N., E-mail: keith.white@manchester.ac.uk [Faculty of Life Sciences, University of Manchester, Manchester M13 9PT (United Kingdom)

    2010-08-01

    The potential for trophic transfer of aluminium (Al) was investigated using a grazing detritivore, the freshwater snail Lymnaea stagnalis, and a predator, the signal crayfish Pacifastacus leniusculus. Snails were exposed to either aqueous Al (500 {mu}g l{sup -1}) in the presence or absence of an inorganic ligand (phosphate (+P); 500 {mu}g l{sup -1}) for 30 days, or kept as unexposed controls. Subcellular partitioning of Al in the snail tissues was characterised using ultracentrifugation. Al content in the soft tissues and the subcellular fractions was measured using inductively coupled plasma atomic emission spectroscopy. Exposed and control snails were fed to individually housed crayfish (n = 6 per group) over 40 days. Water samples, uneaten snail tissue and faeces were collected throughout the experiment in order to assess the fate of Al. Behavioural toxicity to the crayfish was assessed at four time points, and tissue accumulation of Al in soft tissues was measured following a 2-day depuration period. Snails exposed to Al + P accumulated more Al per snail than those exposed to Al only (291 {mu}g vs 206 {mu}g), and also contained a higher proportion of detoxified Al (in inorganic granules and associated with heat stable proteins) (39% vs 26%). There were no significant differences in behavioural activity between the different groups of crayfish at any time point. Crayfish fed snails exposed to only Al accumulated significant levels of Al in their total soft tissues, compared to controls; crayfish fed Al + P-exposed snails did not, even though concentrations of Al in these snails were higher. The highest concentrations of Al were found in the green gland in both crayfish feeding groups, and the gut and hepatopancreas in crayfish fed Al only exposed snails; all of these were significantly higher than in crayfish fed control snails. There was no significant accumulation of Al in the gills or flexor muscle in any group. At least 17% of trophically available Al in the

  20. Comparative study of cadmium and lead accumulations in Cambarus bartoni (Fab. ) (Decapoda, Crustacea) from an acidic and a neutral lake

    Energy Technology Data Exchange (ETDEWEB)

    Keenan, S.; Alikhan, M.A. (Laurentian Univ., Sudbury, Ontario (Canada))

    1991-07-01

    The purpose of the study reported in this paper was to compare concentrations of lead and cadmium in the sediment and water, as well as in the crayfish, Cambarus Bartoni (Fab.) (Decapoda - Crustacea) trapped from an acidic and a neutral lake in the Sudbury district of Northeastern Ontario. Hepatopancreatic, alimentary canal, tail muscles and exoskeletal concentrations in the crayfish are also examined to determine specific tissue sites for these accumulations.

  1. Trophic tangles through time? Opposing direct and indirect effects of an invasive omnivore on stream ecosystem processes.

    Directory of Open Access Journals (Sweden)

    Jonathan W Moore

    Full Text Available Omnivores can impact ecosystems via opposing direct or indirect effects. For example, omnivores that feed on herbivores and plants could either increase plant biomass due to the removal of herbivores or decrease plant biomass due to direct consumption. Thus, empirical quantification of the relative importance of direct and indirect impacts of omnivores is needed, especially the impacts of invasive omnivores. Here we investigated how an invasive omnivore (signal crayfish, Pacifastacus leniusculus impacts stream ecosystems. First, we performed a large-scale experiment to examine the short-term (three month direct and indirect impacts of crayfish on a stream food web. Second, we performed a comparative study of un-invaded areas and areas invaded 90 years ago to examine whether patterns from the experiment scaled up to longer time frames. In the experiment, crayfish increased leaf litter breakdown rate, decreased the abundance and biomass of other benthic invertebrates, and increased algal production. Thus, crayfish controlled detritus via direct consumption and likely drove a trophic cascade through predation on grazers. Consistent with the experiment, the comparative study also found that benthic invertebrate biomass decreased with crayfish. However, contrary to the experiment, crayfish presence was not significantly associated with higher leaf litter breakdown in the comparative study. We posit that during invasion, generalist crayfish replace the more specialized native detritivores (caddisflies, thereby leading to little long-term change in net detrital breakdown. A feeding experiment revealed that these native detritivores and the crayfish were both effective consumers of detritus. Thus, the impacts of omnivores represent a temporally-shifting interplay between direct and indirect effects that can control basal resources.

  2. INTRODUCTION : THE EU-NETWORK CRAYNET- IMPACTS ON FUNDAMENTAL QUESTIONS

    Directory of Open Access Journals (Sweden)

    SOUTY-GROSSET C.

    2005-07-01

    Full Text Available The European network CRAYNET “European crayfish as keystone species-linking science, management and economics with sustainable environmental quality” emphasises knowledge-based management strategies. The CRAYNET meetings concentrate on certain topics: monitoring in conservation and management of natives; interaction between natives and aliens; control of aliens; habitat restoration; reintroduction and restocking; legislation; education. The Irish meeting (Kilkenny, 2003 “The endangered native crayfish Austropotamobius pallipes: bioindicator and heritage species” initiated debates about (1 what is a bioindicator, a flagship species or a heritage species?; (2 the problem of species complexes and the need to clarify and resolve taxonomy before management; and (3 what is meant by biodiversity in the context of European crayfish? The Norwegian meeting (Halden, 2003 “European native, crayfish with a special focus on Astacus astacus: linking socioeconomics and conservation ” involved roundtables about (1 threats to indigenous population of crayfish at a landscape level; (2 exploitation, conservation, legislation; (3 reintroduction of indigenous crayfish, habitat restoration and monitoring; and (4 the urgent need for joint research about pathology. The present meeting (Innsbruck, 2004 “European native crayfish in relation to land-use and habitat deterioration with a special focus on Austropotamobius torrentim” aims to identify the species protection programs, to examine if legislation is working well in protecting vulnerable species, the state of advances about conservation genetics and how to make progress in education of the public. A permanent connection between the 12 core members provides opportunities to check the needed lines of research, to prepare recommendations, and to gather information for an atlas on the distribution of crayfish species in Europe as well as to prepare leaflets for the public.

  3. Contributions to the assessment of Astacus leptodactylus Eschscholtz, 1823 stocks from the Razim-Sinoie lagoonary area (Danube Delta Biosphere Reserve, Romania

    Directory of Open Access Journals (Sweden)

    TÖRÖK Zsolt Csaba

    2013-12-01

    Full Text Available In August 24th- August 30th, 2012 period there was performed a pilot study to assess the Slender clawded or Turkish crayfish (Astacus leptodactylus Eschscholtz, 1823 populations from Golovița Lake and the southern part of the Razim Lake (both of them located in the Danube Delta Biosphere Reserve - DDBR. There were used 10 sets of traps (each set with 10 traps and after 147 – 149 hours of functioning there were captured 45 specimens of A. leptodactylus, the total biomass of the crayfish being 1,768 g, which is a very low if compared with the official crayfish-quotas issued for various other regions of the DDBR. The scarcity in Astacus leptodactylus of the Razim- Sinoie lagoonary area is probably due to the habitat-requirement of this species (although other stressing factors – as plagues affecting the crayfish– could also be considered to explain the phenomenon. In order to harvest the minimum quantity (100 kg of crayfish issued as official quota in case of various other regions of the DDBR, the method involving 10 sets with 10 traps should be continuously used for about 370 days – the costs of activities for such long period (combined with the fact that in case of the exploited crayfish quantities there have to be paid various taxes for the environmental protection authorities makes economically unprofitable the crayfish stock-harvesting (based on the method used in the present study in the Razim and Golovița lakes .

  4. Survival of natural populations of Austropotamobius pallipes in rivers in Bizkaia, Basque Country (North of Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    GARCÍA-ARBERAS L.

    2000-01-01

    Full Text Available Some relict populations of the native crayfish Austropotamobius pallipes have been located in rivers in Bizkaia, (Basque Country, Spain, and its population numbers and dynamics, and habitat conditions have been studied for three years. The first descriptive results are given in this paper. The native crayfish populations must be considered residual because of the disrupted area distribution and highly fluctuating demography of the species. Up to now, the species has been located in more than thirty fluvial areas of relatively high slope and shallow and good quality water. Population characteristics (sex ratio, length and weight relations and length frequency classes are studied in nineteen cases. Maximal relative population numbers are about 100 captures per hour ; these values are correlated to variables of conductivity, hardness, and concentrations of nitrates, nitrites, magnesium, potassium and ammonium. The degree of mineralization must reach a minimum level and, within the values found in the studied rivers, its increase favours the population of crayfish. Management measures to conserve native crayfish must include the protection and improvement of their habitat, prevention of access to it and to the commencement of a genetic study to palliate the phenomenon of endemism. It would also be highly recommendable to begin experimental restocking of riverbeds now without crayfish fauna and with apparently optimum conditions for the establishment of populations of autochthonous crayfish.

  5. Hydrological disturbance diminishes predator control in wetlands.

    Science.gov (United States)

    Dorn, Nathan J; Cook, Mark I

    2015-11-01

    Effects of predators on prey populations can be especially strong in aquatic ecosystems, but disturbances may mediate the strength of predator limitation and even allow outbreaks of some prey populations. In a two-year study we investigated the numerical responses of crayfish (Procambarus fallax) and small fishes (Poeciliidae and Fundulidae) to a brief hydrological disturbance in replicated freshwater wetlands with an experimental drying and large predatory fish reduction. The experiment and an in situ predation assay tested the component of the consumer stress model positing that disturbances release prey from predator limitation. In the disturbed wetlands, abundances of large predatory fish were seasonally reduced, similar to dynamics in the Everglades (southern Florida). Densities of small fish were unaffected by the disturbance, but crayfish densities, which were similar across all wetlands before drying, increased almost threefold in the year after the disturbance. Upon re-flooding, juvenile crayfish survival was inversely related to the abundance of large fish across wetlands, but we found no evidence for enhanced algal food quality. At a larger landscape scale (500 km2 of the Everglades), crayfish densities over eight years were positively correlated with the severity of local dry disturbances (up to 99 days dry) during the preceding dry season. In contrast, densities of small-bodied fishes in the same wetlands were seasonally depressed by dry disturbances. The results from our experimental wetland drought and the observations of crayfish densities in the Everglades represent a large-scale example of prey population release following a hydrological disturbance in a freshwater ecosystem. The conditions producing crayfish pulses in the Everglades appear consistent with the mechanics of the consumer stress model, and we suggest crayfish pulses may influence the number of nesting wading birds in the Everglades.

  6. Molecular characterization of the North American lung fluke Paragonimus kellicotti in Missouri and its development in Mongolian gerbils.

    Science.gov (United States)

    Fischer, Peter U; Curtis, Kurt C; Marcos, Luis A; Weil, Gary J

    2011-06-01

    Human paragonimiasis is an emerging disease in Missouri. To characterize local parasites, we examined crayfish from three rivers. Metacercaeriae consistent with Paragonimus kellicotti were detected in 69%, 67%, and 37% of crayfish from the Big Piney, Huzzah, and Black Rivers, respectively. Sequencing of the second internal transcribed spacer and other DNA markers confirmed the species identification and the presence of identical parasite sequences in clinical specimens from two human cases. Mongolian gerbils were infected by intraperitoneal injection with 3-8 metacercariae. Most gerbils died 15-49 days post-infection. Necropsies showed pulmonary hemorrhage with necrosis, and flukes as long as 8 mm were recovered from intrathoracic tissues. Western blot analysis using P. kellicotti antigen showed a strong antibody response in gerbils 39 days post-infection. These results demonstrate that P. kellicotti is common in Missouri crayfish. The gerbil model may be useful for research on the pathogenesis, immunology, and treatment of paragonimiasis.

  7. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    pp 117-126 Article. Glucohexaose-induced protein phosphatase 2C regulates cell redox status of cucumber seedling · QM CHEN Y YU .... pp 189-223 Review. Investigating the genetic and epigenetic basis of big biological questions with the parthenogenetic marbled crayfish: A review and perspectives · GU¨ NTER VOGT.

  8. Maxent-directed field surveys identify new populations of narrowly endemic habitat specialists

    Directory of Open Access Journals (Sweden)

    Cody M. Rhoden

    2017-07-01

    Full Text Available Background Rare or narrowly endemic organisms are difficult to monitor and conserve when their total distribution and habitat preferences are incompletely known. One method employed in determining distributions of these organisms is species distribution modeling (SDM. Methods Using two species of narrowly endemic burrowing crayfish species as our study organisms, we sought to ground validate Maxent, a commonly used program to conduct SDMs. We used fine scale (30 m resolution rasters of pertinent habitat variables collected from historical museum records in 2014. We then ground validated the Maxent model in 2015 by randomly and equally sampling the output from the model. Results The Maxent models for both species of crayfish showed positive relationships between predicted relative occurrence rate and crayfish burrow abundance in both a Receiver Operating Characteristic and generalized linear model approach. The ground validation of Maxent led us to new populations and range extensions of both species of crayfish. Discussion We conclude that Maxent is a suitable tool for the discovery of new populations of narrowly endemic, rare habitat specialists and our technique may be used for other rare, endemic organisms.

  9. Biological Diversity, Ecological Health and Condition of Aquatic Assemblages at National Wildlife Refuges in Southern Indiana, USA

    Directory of Open Access Journals (Sweden)

    Thomas Simon

    2015-01-01

    Full Text Available The National Wildlife Refuge system is a vital resource for the protection and conservation of biodiversity and biological integrity in the United States. Surveys were conducted to determine the spatial and temporal patterns of fish, macroinvertebrate, and crayfish populations in two watersheds that encompass three refuges in southern Indiana. The Patoka River National Wildlife Refuge had the highest number of aquatic species with 355 macroinvertebrate taxa, six crayfish species, and 82 fish species, while the Big Oaks National Wildlife Refuge had 163 macroinvertebrate taxa, seven crayfish species, and 37 fish species. The Muscatatuck National Wildlife Refuge had the lowest diversity of macroinvertebrates with 96 taxa and six crayfish species, while possessing the second highest fish species richness with 51 species. Habitat quality was highest in the Muscatatuck River drainage with increased amounts of forested habitats compared to the Patoka River drainage. Biological integrity of the three refuges ranked the Patoka NWR as the lowest biological integrity (mean IBI reach scores = 35 IBI points, while Big Oaks had the highest biological integrity (mean IBI reach score = 41 IBI points. The Muscatatuck NWR had a mean IBI reach score of 31 during June, which seasonally increased to a mean of 40 IBI points during summer. Watershed IBI scores and habitat condition were highest in the Big Oaks NWR.

  10. Biological Diversity, Ecological Health and Condition of Aquatic Assemblages at National Wildlife Refuges in Southern Indiana, USA

    Science.gov (United States)

    Morris, Charles C.; Robb, Joseph R.; McCoy, William

    2015-01-01

    Abstract The National Wildlife Refuge system is a vital resource for the protection and conservation of biodiversity and biological integrity in the United States. Surveys were conducted to determine the spatial and temporal patterns of fish, macroinvertebrate, and crayfish populations in two watersheds that encompass three refuges in southern Indiana. The Patoka River National Wildlife Refuge had the highest number of aquatic species with 355 macroinvertebrate taxa, six crayfish species, and 82 fish species, while the Big Oaks National Wildlife Refuge had 163 macroinvertebrate taxa, seven crayfish species, and 37 fish species. The Muscatatuck National Wildlife Refuge had the lowest diversity of macroinvertebrates with 96 taxa and six crayfish species, while possessing the second highest fish species richness with 51 species. Habitat quality was highest in the Muscatatuck River drainage with increased amounts of forested habitats compared to the Patoka River drainage. Biological integrity of the three refuges ranked the Patoka NWR as the lowest biological integrity (mean IBI reach scores = 35 IBI points), while Big Oaks had the highest biological integrity (mean IBI reach score = 41 IBI points). The Muscatatuck NWR had a mean IBI reach score of 31 during June, which seasonally increased to a mean of 40 IBI points during summer. Watershed IBI scores and habitat condition were highest in the Big Oaks NWR. PMID:25632261

  11. 78 FR 41549 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Northern...

    Science.gov (United States)

    2013-07-10

    ... research of these species' habitat, ecology, and life history as described below. Additional insight is... ecology. Rosen and Schwalbe (1988, p. 47) suggested that vegetation such as knotgrass, deergrass, sacaton... in the native fish prey base, bullfrog predation, crayfish interactions, and effects from nonnative...

  12. Browse Title Index

    African Journals Online (AJOL)

    Items 151 - 200 of 719 ... Vol 30, No 2 (2005), Comparing macrophyte herbivory by introduced Louisiana crayfish (Procambarus clarkii) (Crustacea: Cambaridae) and native Dytiscid beetles (Cybister tripunctatus) (Coleoptera: Dytiscidae), in Kenya, Abstract. Sadie K Rosenthal, David M Lodge, Kenneth M Mavuti, Wairimu ...

  13. Fluvial trace fossils in the Middle Siwalik (Sarmatian-Pontian) of ...

    Indian Academy of Sciences (India)

    zoliths, leaf compressions and coal lenses suggest that the tracemakers dominated a floodplain habitat. Point bar deposits host a low ... These tubes bear mixed characters assignable to both crayfish burrows and large-diameter .... iment surface and variable width of burrow lining (black arrows) in them (Leesh section, ...

  14. Author Details

    African Journals Online (AJOL)

    Nzeagwu, OC. Vol 26, No 1 (2008) - Articles Nutrient Composition, Functional and Organoleptic Properties of Complementary Foods Formulated From Sorghum, Groundnut and Crayfish Abstract · Vol 27, No 2 (2009) - Articles Nutrient composition, physical and sensory properties of fruit juices produced from velvet tamarind ...

  15. Socioeconomic Determinants of Income From Fresh and Processed ...

    African Journals Online (AJOL)

    Socioeconomic Determinants of Income From Fresh and Processed Crayfish Marketing in Oron Local Government Area of Akwa Ibom State, Nigeria. ... purchasing cost were significant factors that affected income at 1% while the educational status of marketers alone was significant and positively related to income at 10%.

  16. Growth and carcass characteristics of broiler birds fed agro-by ...

    African Journals Online (AJOL)

    Five agro-by-products were included at different levels (0 %, 5 %, 7.5 %, 10 % and 12.5 %) in the diets of one hundred and twenty (120) broiler birds to evaluate growth performance and carcass characteristics in a study that lasted for eight (8) weeks. The agro-by-products were protein source (crayfish dust and cowpea ...

  17. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    These tubes bear mixed characters assignable to both crayfish burrows and large-diameter rhizoliths. Further work on these tubes is necessary to make more accurate interpretations of those structures. Shallow to moderate burrow depths; intermittent, short-lived colonization events and preservation of rhizoliths and ...

  18. Air photo evidence of historical land cover change in the highlands ...

    African Journals Online (AJOL)

    These land covers, which are dispersed along the fine - grained dendritic stream network, are habitat for crayfish, frogs, and other fauna, yet are also prized locations in the rice - based Malagasy agricultural system. The results of this study suggest that attention be given to highland grassland, wetland and riparian forest ...

  19. Photodynamic effect of Radachlorin on nerve and glial cells.

    Science.gov (United States)

    Neginskaya, M A; Berezhnaya, E V; Rudkovskii, M V; Demyanenko, S V; Uzdensky, A B

    2014-09-01

    Radachlorin, a chlorine-derived photosensitizer, is used currently in photodynamic therapy (PDT) of skin cancer. In this work we studied Radachlorin-PDT effect on peripheral nerve and glial cells that are damaged along with tumor tissue. We used simple model objects - a crayfish stretch receptor that consists of a single sensory neuron surrounded by glial cells and crayfish nerve cord consisting of nerve fibers and ganglia. Radachlorin absorption and emission spectra were registered using spectrophotometer and spectrofluorimeter. Radachlorin accumulation and intracellular localization were studied using the fluorescence microscope. Necrotic and apoptotic cells were visualized using propidium iodide and Hoechst 33342. Neuronal activity was registered using standard electrophysiological methods. Radachlorin absorption spectrum in the physiological van Harreveld saline (pH 7.3) contained maximums at 420 and 654nm. Its fluorescence band 620-700nm had a maximum at 664nm. In the crayfish stretch receptor Radachlorin localized predominantly to the glial envelope and penetrated slightly into the neuron body and axon. Radachlorin rapidly accumulated in the crayfish nerve cord tissue within 30min. Its elimination in the dye-free solution occurred slower: 11% loss for 2h. Radachlorin-PDT inactivated the neuron and induced necrosis of neurons and glial cells and glial apoptosis at concentrations as low as 10(-10)-10(-9)M. Radachlorin rapidly accumulates in the nervous tissue, mainly in glial cells, and demonstrates very high photodynamic efficacy that characterize it as a promising photosensitizer. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Investigating the genetic and epigenetic basis of big biological ...

    Indian Academy of Sciences (India)

    In the last 15 years, considerable attempts have been undertaken to develop the obligately parthenogenetic marbled crayfishProcambarus virginalis as a new model in biology. Its main advantage is the production of large numbers of offspring thatare genetically identical to the mother, making this crustacean particularly ...

  1. Studies on the Biology of Larvae of Clarias albopunctatus (N. & L ...

    African Journals Online (AJOL)

    Clarias albopunctatus larvae, collected from the laboratory hatchlings were on the 4th day of lie, subjected to six different diet consisting of A - Plankton, B - Egg Yolk, C - Beef liver, D - Milk Powder, E - Crayfish trash and F - Soya bean meal. The experiment was maintained at 27.5 ± 5 0oC. Larval weight measurements ...

  2. Amino acid metabolism of Astacus leptodactylus Esch.—III. Studies on the biosynthesis of α- and β-alanine from aspartate

    NARCIS (Netherlands)

    Marrewijk, W.J.A. van; Zandee, D.I.

    1975-01-01

    1. 1. Six hours after injection of 1- or 4-14C-aspartate into the crayfish Astacus leptodactylus almost all radioactivity incorporated was found in the amino acids. 2. 2. From both precursors only the amino acids α-alanine and glutamic acid were labelled. The biosynthesis of α-alanine from

  3. Proceedings of the National Workshop on Containment Area Aquaculture Held in South Padre Island, Texas on 11-15 November 1991

    Science.gov (United States)

    1993-12-01

    profits. enormous supply of groundwater outwelling into the Snake River in the Thousand Springs Production of crayfish is in shallow ponds, area provides... upscale , consumer October 1989, with power to set minimum Proceedings, Containment Area Aquaculture Dillard & Waldrop farm prices. The first master...migration to planned aquaculture activities with project geological conditions groundwater ; good disposal requirements. At least the following foundatton

  4. Invertebrate grazing during the regenerative phase affects the ultimate structure of macrophyte communities

    NARCIS (Netherlands)

    Elger, A.F.; Willby, N.; Cabello-Martinez, M.

    2009-01-01

    1. Although the biomass of freshwater macrophytes consumed by invertebrate herbivores (excluding crayfish) is usually low, there is growing evidence that invertebrates do exert a structuring effect on macrophyte communities. To explain this, we postulated that the effect of invertebrates may be

  5. current status of paragonimiasis in old netim 1 akamkpa local ...

    African Journals Online (AJOL)

    LUCY

    periwinkle, water snail, crayfish and crab as intermediate host. Periwinkle or water snails serve as first intermediate host while ... stain and mucus. Specimen were prepared from spots containing blood stain. DOUBLE WET SMEAR TECHNIQUE. A drop of saturate saline was placed in the centre of one half of a microscope ...

  6. Agro-science

    African Journals Online (AJOL)

    AGRO-SCIENCE

    spp): Mixture of boiled pigeon pea; cracked, soaked, and steamed cocoyama, onion, pepper, salt, fermented and sliced oil bean seed. (Pentaclethra macrophylla), and crayfish. (optional). AK-Akara (Vigna unguiculata): Wet milled dehulled cowpea whipped and mixed with pepper, onions, salt and deep fried in balls in.

  7. Impacts of Flooding Regime Modification on Wildlife Habitats of Bottomland Hardwood Forests in the Lower Mississippi Valley.

    Science.gov (United States)

    1981-10-01

    Fredrickson (Gaylord Memorial Lab, University of Missouri-Columbia, Puxico, Missouri) personal communication (Nov 1980). 16 fI (Liguidambar...and elderberry (Sambucus canadensis) while in the unchannelized area, switch cane (Arundinaria gigantea), blueberry (Vaccinium spp.), and sebastian... blueberry , and other fruits are taken seasonally (USDA 1971). Animal foods include crayfish, clams, insects, earthworms, arthropods, amphibians and

  8. AUSTROPOTAMOBIUS TORRENTIUM AS AN INDICATOR FOR HABITAT QUALITY IN RUNNING WATERS?

    Directory of Open Access Journals (Sweden)

    PÖCKL M.

    2005-07-01

    Full Text Available In the present study we tried to quantify the indication value of A. torrentium referring to habitat quality. This variable is expressed as the availability of appropriate refuge stones on the bottom and banks of running waters. The brooks occupied by the indigenous stone crayfish in Lower Austria show a high variability in the current velocity and substrate heterogeneity. Having some experience in hand searching we assumed that the distribution pattern of the crayfish on the stream bed is strongly correlated with the distribution of cobble and pebbles within a certain grain size. The aim of our study was to quantify the dependence of the shelter requirements for A. torrentium on grain size and water velocity, as well as the seasonal mobility of the crayfish. Shelters where velocity exceeded 25 cm s-1 were not occupied. Pebbles with a bearing surface greater than 300 cm2 were preferred, and the probability of crayfish occupation rose quickly as the stone’s bearing surface increased up to 900 cm2. Most individuals changed their location only a few meters (median 4 m. The distance from the point of first capture increased only little within the length of time passed until re-capture, suggesting a conservative use of space.

  9. Nutritional evaluation of the giant grassropper (Zonocerus ...

    African Journals Online (AJOL)

    The biological value of giant grasshopper protein (Zonocerus variegatus) was evaluated by comparing the weight gained, food efficiency ratio (FER), protein efficiency ratio (PER) of rats fed standard laboratory chow with that of rats fed giant grasshopper, Soyabean(Glycine max) and crayfish. The effect of high fibre content ...

  10. Fulltext PDF

    Indian Academy of Sciences (India)

    Although the decapods are well investigated with respect to diseases in the framework of environmental monitoring, aquaculture biosecurity pro- grams and seafood quality controls, there are only a few cases of neoplasias known. In the marbled crayfish, tumours have not been found yet. This is interesting because marbled.

  11. Biomimetics and astronomical X-ray optics

    Science.gov (United States)

    Hudec, R.; Remisova, K.

    2017-07-01

    Some sea and water animals have strange mirror eyes which have (or might have) potential application in science and technology in general and in X—ray astrophysics in particular. While the principles of mirror eyes of decapods (lobsters, crayfishes) are already applied in space and ground—based imaging experiments, the mirror eyes of specific fishes are still very little investigated.

  12. Fulltext PDF

    Indian Academy of Sciences (India)

    Günter Vogt

    2018-02-14

    Feb 14, 2018 ... genetic investigations with the marbled crayfish can help clarifying the role of epigenetic mechanisms in gene regulation, tissue specification, adult stem cell regulation, cell ageing, organ regeneration and disease susceptibility. Marbled .... and count, principally facilitating correlations between phenotype ...

  13. Mitochondrial genomes and comparative genomics of Aphanomyces astaci and Aphanomyces invadans

    Science.gov (United States)

    The genus Aphanomyces (Saprolegniales, Oomycetes) includes species with variety of ecologies from saprotrophs to plant and animal parasites. Two important species in this genus are Aphanomyces astaci that causes the crayfish plague and its close relative, Aphanomyces invadans, which causes the epizo...

  14. Author Details

    African Journals Online (AJOL)

    Abraham, JT. Vol 5, No 1 (2006) - Articles Abundance of Pseudotolithus elongatus in the Niger Delta area - a case study in the Cross River estuary. Abstract PDF · Vol 14, No 1 (2015) - Articles Parasites of crayfish (P. clarki) and lobsters (Macrobrachium vollenhovenic) as indicators of metallic pollution in great, Kwa river, ...

  15. Global Journal of Agricultural Sciences - Vol 14, No 1 (2015)

    African Journals Online (AJOL)

    Parasites of crayfish (P. clarki) and lobsters (Macrobrachium vollenhovenic) as indicators of metallic pollution in great, Kwa river, Nigeria · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. JT Abraham, GO Oloko, EM Ikpeme, 27-36. http://dx.doi.org/10.4314/gjass.v14i1.4 ...

  16. ROUNDTABLE SESSION 2: DOES LEGISLATION WORK IN PROTECTING VULNERABLE SPECIES?

    Directory of Open Access Journals (Sweden)

    HOLDICH D. M.

    2005-07-01

    Full Text Available As a result of discussions held at the Innsbruck CRAYNET meeting and the answers given to a subsequent questionnaire sent out to the National Co-ordinators of the 11 countries/regions, it is clear that most European countries aim at trying to protect their indigenous crayfish species (ICS from overexploitation, habitat modification, pollution, and spread of non-indigenous crayfish species (NICS and crayfish plague. Two detailed case studies are given for Austria and England plus a summary of the questionnaires. These clearly illustrate the different attitudes of countries to protecting and managing their ICS and NICS. The situation is highly complex and differs depending upon whether or not there is a tradition for eating crayfish. Consequently, harmonisation of national and regional regulations for ICS and NICS in Europe may not be possible in the short term. In many cases legislation has not prevented further destruction of populations of ICS and the spread of NICS. However, without such legislation the situation could have been a lot worse and some ICS could already have become critically endangered. The continued efforts by the crayfish community and national authorities have resulted in a scenario where there are still some countries without NICS, and in most European countries there are specific areas with numerous, viable populations of ICS that are considered valuable and are protected by the authorities as well as by local people. The situation has recently been improved by providing protection for Austropotamobius torrentium under Annex II of the EU Habitats Directive. A major objective must be to develop methods for eradicating nuisance populations of NICS before they spread any further.

  17. Population-Level Metrics of Trophic Structure Based on Stable Isotopes and Their Application to Invasion Ecology

    Science.gov (United States)

    Jackson, Michelle C.; Donohue, Ian; Jackson, Andrew L.; Britton, J. Robert; Harper, David M.; Grey, Jonathan

    2012-01-01

    Biological invasions are a significant driver of human-induced global change and many ecosystems sustain sympatric invaders. Interactions occurring among these invaders have important implications for ecosystem structure and functioning, yet they are poorly understood. Here we apply newly developed metrics derived from stable isotope data to provide quantitative measures of trophic diversity within populations or species. We then use these to test the hypothesis that sympatric invaders belonging to the same functional feeding group occupy a smaller isotopic niche than their allopatric counterparts. Two introduced, globally important, benthic omnivores, Louisiana swamp crayfish (Procambarus clarkii) and carp (Cyprinus carpio), are sympatric in Lake Naivasha, Kenya. We applied our metrics to an 8-year data set encompassing the establishment of carp in the lake. We found a strong asymmetric interaction between the two invasive populations, as indicated by inverse correlations between carp abundance and measures of crayfish trophic diversity. Lack of isotopic niche overlap between carp and crayfish in the majority of years indicated a predominantly indirect interaction. We suggest that carp-induced habitat alteration reduced the diversity of crayfish prey, resulting in a reduction in the dietary niche of crayfish. Stable isotopes provide an integrated signal of diet over space and time, offering an appropriate scale for the study of population niches, but few isotope studies have retained the often insightful information revealed by variability among individuals in isotope values. Our population metrics incorporate such variation, are robust to the vagaries of sample size and are a useful additional tool to reveal subtle dietary interactions among species. Although we have demonstrated their applicability specifically using a detailed temporal dataset of species invasion in a lake, they have a wide array of potential ecological applications. PMID:22363724

  18. CONSERVATION MANAGEMENT AND LEGISLATION THE UK EXPERIENCE

    Directory of Open Access Journals (Sweden)

    SIBLEY P. J.

    2003-04-01

    Full Text Available Underpinning the conservation management of Austropotamobius pallipes in the UK is the process of monitoring and reporting crayfish distribution. Should the current trend in the decline of A. pallipes continue, the species could be virtually extinct in mainland Britain within 30 years (SIBLEY, 2003. Conversely, if the increase in the distribution of non-indigenous crayfish species (NICS continues at its current rate, the distribution (by 10 km squares of these species could double within 15 years. These forward projections are based on a number of possibly unreliable assumptions; they illustrate however the magnitude of the challenge facing those concerned with the conservation of A. pallipes in the UK at this time. Recent work in crayfish conservation management in the UK has yielded guidance in several areas including monitoring, habitat enhancement and a re-introduction protocol for A. pallipes (KEMP and HILEY, 2003. Similarly, scientific research continues to inform our understanding of the movement and behaviour of NICS and explores new methods for the potential management of these species. In addition, the protection afforded to A. pallipes by current legislation is key to the long-term survival prospects of the species, albeit with a probable fragmented distribution, across the British Isles and continental Europe. Legal provisions in the UK derive in part from European instructions (e.g. EC Habitats and Species Directive and also from national legislation (e.g. Salmon and Freshwater Fisheries Act (1975 and the Wildlife and Countryside Act (1981. Also, a raft of “quasi-legislation” exists which requires responsible organisations in the UK to implement the white-clawed crayfish biodiversity action plan (BAP. Altogether these provisions constitute a considerable volume of legal protection for crayfish and provide the legal framework on which UK management policy and practice are based.

  19. Trace elements in bed sediments and aquatic invertebrates from three streams in Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, S. [Geological Survey, Carson City, NV (United States). Water Resources Div.

    1995-12-31

    In September 1992, the US Geological Survey, as part of the National Water Quality Assessment Program, collected crayfish (Pacifastacus Ieniusculus and Procambarus clarkii), asiatic clam (Corbicula fluminea), caddis-fly larvae (Hydropsyche spp.) and bed-sediment samples from the Truckee and Carson Rivers, and Las Vegas Wash in Nevada and analyzed them for selected trace elements. This report describes and compares the concentrations of arsenic, copper, manganese, mercury, silver, and zinc in those samples. In the Truckee and Carson Rivers, concentrations of the six trace elements in aquatic invertebrate samples are similar to concentrations measured in bed sediments. In the Truckee River, concentrations of these elements in crayfish and bed-sediment samples were highest in the Reno-Sparks urban area. In the Carson River, arsenic and copper are highest in bed-sediment samples upstream of Carson City due to geothermal springs and acid-mine drainage from an abandoned sulfur mine; concentrations of manganese, mercury, silver, and zinc were highest in bed-sediment samples collected downstream of the Carson City urban area due to historic gold and silver mining, and urban runoff. The highest mercury concentration in crayfish tissue, 48 {micro}g/g dry weight, was measured in a sample from the lower Carson River. In Las Vegas Wash, bed-sediment concentrations were lower than those in the Truckee and Carson Rivers; but, trace-element concentrations in crayfish tissue tended to be higher than those in bed sediment. Samples collected during this study show that trace elements are enriched in the bed sediments of all three rivers and are bioavailable. Trace-element concentrations among samples of crayfish, asiatic clam, and caddis-fly larvae showed little similarity.

  20. Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2010-30 November 2010.

    Science.gov (United States)

    Agostini, Cecilia; Agudelo, P A; Bâ, K; Barber, P A; Bisol, Paolo Maria; Brouat, C; Burgess, Treena I; Calves, I; Carrillo Avila, Mauricio; Chow, S; Cordes, Lisa; Da Silva, D; Dalecky, A; De Meester, L; Doadrio, Ignacio; Dobigny, G; Duplantier, J M; Evison, Sophie E F; Ford, Rebecca; Fresneau, Dominique; Galetti, Pedro M; Gauthier, P; Geldof, S; Granjon, L; Guérin, F; St J Hardy, Giles E; Hernandez Escobar, Carlos; Hima, K; Hu, Juan; Huang, Luqi; Humeau, L; Jansen, B; Jaquemet, S; Jiang, Zhi-Qiang; Jung, Sung-Ju; Kim, Bong-Seok; Kim, Cheol-Hee; Kim, Jong-Oh; Lai, Choay-Hoong; Laroche, J; Lavergne, E; Lawton-Rauh, A; Le Corre, M; Leach, M M; Lee, Jehee; Leo, Audrey E; Lichtenzveig, Judith; Lin, Lin; Linde, Celeste C; Liu, Shu-Fang; Marino, Ilaria A M; McKeown, Niall J; Nohara, K; Oh, Myung-Joo; Okamoto, H; Oliver, Richard; Olivera Angel, Martha; Ornelas-García, Claudia Patricia; Orsini, L; Ostos Alfonso, Henry; Othman, A S; Papetti, Chiara; Patarnello, Tomaso; Pedraza-Lara, Carlos; Piller, Kyle R; Poteaux, Chantal; Requier, J-B; Roziana, M K; Semba, Y; Sembene, M; Shah, Ramisah M; Shahril, A R; Shao, Aijuan; Shaw, Paul W; Song, Liangke; Souza Ferreira, Ronara; Su, Yong-Quan; Suzuki, N; Tatard, C; Taylor, Katherine M; Taylor, Paul W J; Thiam, M; Valbuena, Ruben; Wang, He; Yang, Byung-Gyoo; Yuan, Qingjun; Zajonz, U; Zane, Lorenzo; Zhu, Ling; Zhuang, Zhi-Meng; Zulaiha, A R

    2011-03-01

    This article documents the addition of 277 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Ascochyta rabiei, Cambarellus chapalanus, Chionodraco hamatus, Coptis omeiensis, Cynoscion nebulosus, Daphnia magna, Gerbillus nigeriae, Isurus oxyrinchus, Lates calcarifer, Metacarcinus magister, Oplegnathus fasciatus, Pachycondyla verenae, Phaethon lepturus, Pimelodus grosskopfii, Rotylenchulus reniformis, Scomberomorus niphonius, Sepia esculenta, Terapon jarbua, Teratosphaeria cryptica and Thunnus obesus. These loci were cross-tested on the following species: Austropotamobius italicus, Cambarellus montezumae, Cambarellus puer, Cambarellus shufeldtii, Cambarellus texanus, Chionodraco myersi, Chionodraco rastrospinosus, Coptis chinensis, Coptis chinensis var. brevisepala, Coptis deltoidea, Coptis teeta, Orconectes virilis, Pacifastacus leniusculus, Pimelodus bochii, Procambarus clarkii, Pseudopimelodus bufonius, Rhamdia quelen, Sepia andreana, Sepiella maindroni, Thunnus alalunga, Thunnus albacares, Thunnus maccoyii, Thunnus orientalis, Thunnus thynnus and Thunnus tonggol. © 2011 Blackwell Publishing Ltd.

  1. Detection of Mycobacterium ulcerans subsp. shinshuense DNA from a water channel in familial Buruli ulcer cases in Japan.

    Science.gov (United States)

    Luo, Yuqian; Degang, Yang; Ohtsuka, Mikio; Ishido, Yuko; Ishii, Norihisa; Suzuki, Koichi

    2015-01-01

    To determine if Mycobacterium ulcerans subsp. shinshuense is present in the common living environment in a case of familial concurrent occurrence of Buruli ulcer in Japan. Environmental samples were collected primarily from a water channel in the patient's residence. A combination of whole-genome amplification, touchdown PCR and DNA sequencing was used to detect M. ulcerans subsp. shinshuense DNA. M. ulcerans subsp. shinshuense DNA was detected in a crayfish sampled in July, but not in other samples including a crayfish sampled in October. These findings support an association between contaminated aquatic environments and Buruli ulcer in Japan. The data also suggest dynamic seasonal appearance of the pathogen in the environment may contribute to the seasonal variation of Buruli ulcer occurrence in Japan.

  2. Pleuropulmonary Paragonimiasis mimicking Pulmonary Tuberculosis - A Report of Three Cases

    Directory of Open Access Journals (Sweden)

    Singh T

    2005-01-01

    Full Text Available Paragonimiasis is an important cause of pulmonary disease worldwide. Infection in humans mainly occurs by ingestion of raw or undercooked freshwater crabs or crayfishes. The disease is well known in endemic regions of Asian countries, where culturally based methods of food preparation foster human transmission. Three patients with clinical and radiological features compatible with pulmonary tuberculosis had been treated for tuberculosis without remedy despite an inability to demonstrate acid fast bacilli in sputum smears. All patients had history of ingestion of raw crabs and crayfishes. The confirmed diagnosis of pleuropulmonary paragonimiasis was made based on the demonstration of Paragonimus eggs in the sputum, and high absolute eosinophilia in their peripheral blood and pleural fluid. All the patients had been treated with praziquantel successfully.

  3. Molecular systematics and evolution of Regina and the thamnophiine snakes.

    Science.gov (United States)

    Alfaro, M E; Arnold, S J

    2001-12-01

    Snakes of the tribe Thamnophiini represent an ecologically important component of the herpetofauna in a range of habitats across North America. Thamnophiines are the best-studied colubrids, yet little is known of their systematic relationships. A molecular phylogenetic study of 32 thamnophiine species using three complete mitochondrial genes (cytochrome b, NADH dehydrogenase subunit 2, and 12S ribosomal DNA) recovered a well-supported phylogeny with three major clades: a garter snake group, a water snake group, and a novel semifossorial group. The historically contentious genus Regina, which contains the crayfish-eating snakes, is polyphyletic. The phylogeographic pattern of Thamnophis is consistent with an hypothesis of at least one invasion of northern North America from Mexico.

  4. Mechanisms That Generate Resource Pulses in a Fluctuating Wetland.

    Directory of Open Access Journals (Sweden)

    Bryan A Botson

    Full Text Available Animals living in patchy environments may depend on resource pulses to meet the high energetic demands of breeding. We developed two primary a priori hypotheses to examine relationships between three categories of wading bird prey biomass and covariates hypothesized to affect the concentration of aquatic fauna, a pulsed resource for breeding wading bird populations during the dry season. The fish concentration hypothesis proposed that local-scale processes concentrate wet-season fish biomass into patches in the dry season, whereas the fish production hypothesis states that the amount of dry-season fish biomass reflects fish biomass production during the preceding wet season. We sampled prey in drying pools at 405 sites throughout the Florida Everglades between December and May from 2006-2010 to test these hypotheses. The models that explained variation in dry-season fish biomass included water-level recession rate, wet-season biomass, microtopography, submerged vegetation, and the interaction between wet-season biomass and recession rate. Crayfish (Procambarus spp. biomass was positively associated with wet-season crayfish biomass, moderate water depth, dense submerged aquatic vegetation, thin flocculent layer and a short interval of time since the last dry-down. Grass shrimp (Palaemonetes paludosus biomass increased with increasing rates of water level recession, supporting our impression that shrimp, like fish, form seasonal concentrations. Strong support for wet-season fish and crayfish biomass in the top models confirmed the importance of wet-season standing stock to concentrations of fish and crayfish the following dry season. Additionally, the importance of recession rate and microtopography showed that local scale abiotic factors transformed fish production into the high quality foraging patches on which apex predators depended.

  5. Large-Scale Operations Management Test of Use of the White Amur for Control of Problem Aquatic Plants. Selected Life History Information of Animal Species on Lake Conway, Florida.

    Science.gov (United States)

    1982-08-01

    Animal Life Encyclopedia , Vol 6, Van Nostrand Reinhold, New York. Guillory, V. 1979. "Large-Scale Operations Management Test of Use of the White Amur for...Siguodon hispidUs 6 Northern racoon Procyon lotor 7 Neartic river otter Lutra ca ndensis Herpetofauna Species 1 Florida cricket frog Acris gryllus 2...catfish, gold- fish, carp, bass, silversides), tadpoles, crayfish, frogs, earthworms, crickets , grass- hoppers, and small snakes and mammals g

  6. Biologie rozmnožování u raků

    OpenAIRE

    NIKSIRAT HASHJIN, Hamid

    2014-01-01

    The ultrastructure of spermatozoa from six crayfish species were described. The acrosome complex and nucleus are located at the anterior and posterior of the spermatozoon, respectively. The acrosome complex organelle is divided into two main parts: the main body of the acrosome that is a dense inverted cup-shaped structure and organized into three layers of differing electron densities and extended parallel filaments, and the sub-acrosome zone occupying the central part of the acrosome comple...

  7. Limestone Creek, Local Flood Protection, Fayetteville, New York

    Science.gov (United States)

    1990-08-01

    adverse impact on water chemistry, salinity , oaor, color, dissolved gas levels, water nutrient content, creek degradation, and water temperature...p. Scud 1 22 1 156 180 Gammarus Mayfly 25 1 26 Baetis Mayfly 54 54 Heptaaenia C ly 12 7 19 Hydropsyche Caddisfly 1 2 3 Unidentified so. whirligig...earthworm Aeolosoma - - 1 - NS NS - - Aquatic sowbug Asellus spp. - - - - NS NS - 1 Scud Gammarus spp. 2 4 3 13 NS NS 56 2 Crayfish Cambarus bartoni

  8. Water Operations Technical Support Program: Techniques for Evaluating Aquatic Habitats in Rivers, Streams, and Reservoirs. Proceedings of a Workshop Held in Vicksburg, Mississippi on 8-10 August 1989.

    Science.gov (United States)

    1991-08-01

    restrictive. The major functional groups of macroinvertebrates in streams are shredders (feeders on CPOM such as leaf litter ), scrapers (raspers of...pattern, which resembles the pattern of veins in an oak leaf (Figure 2). A rectangular pattern may develop where geologic controls such as jointing...crayfish; grass shrimp; and river shrimp. In North America, isopods are most common in small streams where they feed in leaf packs and on the

  9. The Hydrodynamic Distinctiveness of Living Organisms: Communication in Complex Hydraulic Environments

    Science.gov (United States)

    Johnson, M.

    2015-12-01

    Animals make decisions about the suitability of habitat and their reaction to other organisms based on the sensory information that they first obtain. This information is transmitted, masked and filtered by fluvial processes, such as turbulent flow. Despite governing how animals interact with the environment, limited attention has been paid to the controls on the propagation of sensory signals through rivers. Some animals interpret hydraulic events and use the characteristics of wakes to sense the presence of other organisms. This implies that at least some animals can differentiate turbulent flow generated by the presence of living organisms from ambient environmental turbulence. We investigate whether there are specific flow characteristics, distinct from the ambient environment, that potentially flag the presence of organisms to other animals. ADV and PIV measurements in a series of laboratory flume experiments quantified the flow around living Signal Crayfish (Pacifastacus leniusculus) and two inanimate objects of equivalent shape and size. Experiments were repeated across a gradient of turbulence intensities generated over nine combinations of flow velocity and relative submergence. Flows downstream of living crayfish were distinct from inanimate objects, with greater turbulent intensities, higher energy in low- to intermediate frequencies, and flow structures that were less coherent in comparison to those measured downstream of inanimate objects. However, the hydrodynamic signature of crayfish became masked as the intensity of ambient turbulence exceeded that generated by living crayfish. These results demonstrate the importance of the fluvial processes in the transmission of sensory information and suggest that the ability of animals to perceive hydraulic signatures is likely to be limited in many situations in rivers. Thus, animals may need to rely on other senses, such as sight or hearing, especially where depth is shallow relative to grain size.

  10. Trace elements in shellfish on the Danish market.

    Science.gov (United States)

    Petersen, A; Mortensen, G K

    1994-01-01

    Different kinds of shellfish have been investigated for their contents of the trace elements cadmium, lead, mercury, nickel, chromium, arsenic and selenium. The investigation included shrimps, mussels, lobster, langoustine, crayfish, crab claws and oyster. None of the Danish action levels for cadmium, lead and mercury respectively were exceeded, but the highest concentration of lead was very close to the Danish action levels. Shellfish do not contribute significantly to the intake of the trace elements investigated.

  11. [Interaction of alpha-(125)latrocrustotoxin with nerve cell membranes from the river crab Astacus astacus].

    Science.gov (United States)

    Krasnoperov, V G; Shamotienko, O G; Grishin, E V

    1991-05-01

    alpha-Latrocrustatoxin, the crustacean-specific neurotoxin from the venom of the black widow spider Latrodectus mactans tredecimguttatus was radioactively labelled with Bolton-Hunter reagent to the specific activity of 160 Ci/mmol with retention of the biological activity. A highly specific binding of radioactive toxin on plasmatic membranes from the crayfish Astacus astacus nerve cells with Bmax = 0.04 pmol binding toxin/mg membrane protein and Kd = 0.7 x 10(-10) M was demonstrated.

  12. 40 CFR 180.274 - Propanil; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... (3, 4-DCA) in or on the following food commodities: Commodity Parts per million Cattle, fat 0.10 Cattle, meat 0.05 Cattle, meat byproducts 1.0 Crayfish 0.05 Egg 0.30 Goat, fat 0.10 Goat, meat 0.05 Goat....05 Horse, meat byproducts 1.0 Milk 0.05 Poultry, fat 0.05 Poultry, meat 0.10 Poultry, meat byproducts...

  13. The activity of glutathione S-transferase in hepatopancreas of Procambarus clarkii: seasonal variations and the influence of environmental pollutants.

    Science.gov (United States)

    Nies, E; Almar, M M; Hermenegildo, C; Monsalve, E; Romero, F J

    1991-01-01

    1. The glutathione S-transferase activity in hepatopancreas of the American red crayfish Procambarus clarkii after 15 days' acclimatization in tap water aquaria was measured in specimens collected monthly for a whole year, and shows seasonal variation. 2. Previous data on the environmental pollution of Lake Albufera suggest a possible correlation with the activity tested in the different seasons of the year considering the results of non-acclimatized animals.

  14. REINTRODUCTION OF ASTACUS ASTACUS L. IN EAST TYROL, AUSTRIA

    Directory of Open Access Journals (Sweden)

    SINT D.

    2004-01-01

    Full Text Available In Tyrolean like in other European freshwaters, crayfish populations decreased in numbers and qualities. They are today regarded as endangered animals. The Astacus astacus (Linnaeus, 1758 population of historical evidence in Tristacher See and its out flowing stream Tristacher Seebach (mentioned already by Emperor Maximilian I in 1504 became extinct in the late 1990s. After the restoration of the stream we started a species conservation programme with various specific protection measures, including breeding and restocking of young-of-the-year and adult A. astacus. Females, after having released their young in the hatchery, were stocked together with males in a 200-m-section of Tristacher Seebach, previously populated by A. astacus. In October, the young-of-theyear crayfish were released in another area of the same stream. To show the importance of habitat diversity and shelter, four sites for introduction were selected describing a gradient of habitat diversity. We monitored general characteristics of the population (sex, size, densities and compared them to habitat conditions. Individual crayfish were tagged with gloss-paint pens to allow an observation of their movements between the different sections over the summer months. We found significant results when migration behaviour, population assemblage and habitat conditions were compared. Males frequently moved longer distances than females. Migration length corresponded to the gradient of available structures and shelter. Heterogeneous riprap was somewhat preferred to artificial shelter like bricks or plastic tubes. Sections without additional shelter showed almost no presence of crayfish. Sex and size distribution within assemblages appeared also to be affected by habitat conditions. Our results indicate the importance of monitoring in species reintroduction projects, as this research demonstrated the immediate effect and importance of habitat structure and affirmed the success of the

  15. Environmental Assessment for the Aeromedical Evacuation Formal Training Unit, Wright-Patterson Air Force Base

    Science.gov (United States)

    2012-05-01

    composition. Hydrogeology extends the study of the subsurface to water- bearing structures. Hydrogeological information helps in the assessment of...the proposed project area did not encounter evidence of burrows (crayfish or small mammals) occurring within open wetlands for winter hibernation with...population. Tract 2803 has a higher percentage of females of child- bearing age (15 to 44 years) and lower percentage of individuals 65 and older and

  16. Predicting wading bird and aquatic faunal responses to ecosystem restoration scenarios

    Science.gov (United States)

    Beerens, James M.; Trexler, Joel C.; Catano, Christopher P.

    2017-01-01

    In large-scale conservation decisions, scenario planning identifies key uncertainties of ecosystem function linked to ecological drivers affected by management, incorporates ecological feedbacks, and scales up to answer questions robust to alternative futures. Wetland restoration planning requires an understanding of how proposed changes in surface hydrology, water storage, and landscape connectivity affect aquatic animal composition, productivity, and food-web function. In the Florida Everglades, reintroduction of historical hydrologic patterns is expected to increase productivity of all trophic levels. Highly mobile indicator species such as wading birds integrate secondary productivity from aquatic prey (small fishes and crayfish) over the landscape. To evaluate how fish, crayfish, and wading birds may respond to alternative hydrologic restoration plans, we compared predicted small fish density, crayfish density and biomass, and wading bird occurrence for existing conditions to four restoration scenarios that varied water storage and removal of levees and canals (i.e. decompartmentalization). Densities of small fish and occurrence of wading birds are predicted to increase throughout most of the Everglades under all restoration options because of increased flows and connectivity. Full decompartmentalization goes furthest toward recreating hypothesized historical patterns of fish density by draining excess water ponded by levees and hydrating areas that are currently drier than in the past. In contrast, crayfish density declined and species composition shifted under all restoration options because of lengthened hydroperiods (i.e. time of inundation). Under full decompartmentalization, the distribution of increased prey available for wading birds shifted south, closer to historical locations of nesting activity in Everglades National Park.

  17. Growth, yield, plant quality and nutrition of basil (Ocimum basilicum L. under soilless agricultural systems

    Directory of Open Access Journals (Sweden)

    Subhrajit Saha

    2016-12-01

    Full Text Available Traditional agricultural systems are challenged by globally declining resources resulting from climate change and growing population. Alternative agricultural practices such as aquaponics (includes crop plant and aquatic species and hydroponics (includes crop plant only have the potential to generate high yield per unit area using limited land, water, and no soil. A soilless agricultural study was conducted at the Georgia Southern University, Statesboro, GA, USA from August to November, 2015. The growth, yield, quality, and nutrition of basil (Ocimum basilicum L. cultivar Aroma 2, were compared between aquaponic and hydroponic systems using crayfish (Procambarus spp. as the aquatic species. Non-circulating floating raft systems were designed using 95 L polyethylene tanks. Equal amounts of start-up fertilizer dose were applied to both systems. The objective was to understand how the additional nutritional dynamics associated with crayfish influence the basil crop. Both fresh and dry basil plant weights were collected after harvest, followed by leaf nutrient analysis. Leaf chlorophyll content, water pH, nitrogen and temperature were measured periodically. Aquaponic basil (AqB showed 14%, 56%, and 65% more height, fresh weight, and dry weight, respectively, compared to hydroponic basil (HyB. It is logical to assume that crayfish waste (excreta and unconsumed feed has supplied the additional nutrients to AqB, resulting in greater growth and yield. The chlorophyll content (plant quality or leaf nutrients, however, did not differ between AqB and HyB. Further research is needed to investigate aquaponic crayfish yield, overall nutritional dynamics, cost-benefit ratio, and other plant characteristics under soilless systems.

  18. Nerve membrane ion channels as the target site of environmental toxicants

    Energy Technology Data Exchange (ETDEWEB)

    Narahashi, T.

    1987-04-01

    There are many environmentally important chemicals which exhibit potent effects on the nervous system. Since nerve excitation takes place in a fraction of a second, electrophysiological methods provide the authors with the most straightforward approach to the study of the mechanisms of action of environmental toxicants on the nervous system. Aquatic animals such as crayfish, lobster, squid, and marine snails represent extremely useful materials for such electrophysiological studies, because much of the authors knowledge of nerve excitation is derived from those animals. Nerve excitation takes place as a result of opening and closing of ion channels of the membrane. These functions are independent of metabolic energy, and can be measured most effectively by voltage clamp techniques as applied to the giant axons of the crayfish and the squid. Patch clamp techniques developed during the past 10 years have added a new dimension to the electrophysiological investigation. These techniques allow them to measure the activity of individual ion channels, thereby making it possible to analyze the interaction of toxic molecules directly with single ion channels. Examples are given summarizing electrophysiological studies of environmental neurotoxicants. The abdominal nerve cords and neuromuscular preparations isolated from the crayfish are convenient materials for bioassay of certain environmental toxicants such as pyrethroids, chlorinated hydrocarbons, and other insecticides. Only a small fraction of the flux through the sodium channel, less than 1%, must be modified by pyrethroids for the animal to develop symptoms of poisoning. Such a toxicological application from channel to animal is important is understanding the potent toxic effect.

  19. The role of NO synthase isoforms in PDT-induced injury of neurons and glial cells

    Science.gov (United States)

    Kovaleva, V. D.; Berezhnaya, E. V.; Uzdensky, A. B.

    2015-03-01

    Nitric oxide (NO) is an important second messenger, involved in the implementation of various cell functions. It regulates various physiological and pathological processes such as neurotransmission, cell responses to stress, and neurodegeneration. NO synthase is a family of enzymes that synthesize NO from L-arginine. The activity of different NOS isoforms depends both on endogenous and exogenous factors. In particular, it is modulated by oxidative stress, induced by photodynamic therapy (PDT). We have studied the possible role of NOS in the regulation of survival and death of neurons and surrounding glial cells under photo-oxidative stress induced by photodynamic treatment (PDT). The crayfish stretch receptor consisting of a single identified sensory neuron enveloped by glial cells is a simple but informative model object. It was photosensitized with alumophthalocyanine photosens (10 nM) and irradiated with a laser diode (670 nm, 0.4 W/cm2). Antinecrotic and proapoptotic effects of NO on the glial cells were found using inhibitory analysis. We have shown the role of inducible NO synthase in photoinduced apoptosis and involvement of neuronal NO synthase in photoinduced necrosis of glial cells in the isolated crayfish stretch receptor. The activation of NO synthase was evaluated using NADPH-diaphorase histochemistry, a marker of neurons expressing the enzyme. The activation of NO synthase in the isolated crayfish stretch receptor was evaluated as a function of time after PDT. Photodynamic treatment induced transient increase in NO synthase activity and then slowly inhibited this enzyme.

  20. Risk assessment of pet-traded decapod crustaceans in the Republic of Kazakhstan, the leading country in Central Asia

    Directory of Open Access Journals (Sweden)

    Uderbayev Talgat

    2017-01-01

    Full Text Available The pet trade with decapod crustaceans has been considered one of the main pathway of introduction of these animals worldwide. As the leading markets in this regards are the Czech Republic, Germany and the USA. Central Asia is not perceived as an important market with ornamental decapod crustaceans. Despite this assumption, we found at least 16 species of freshwater shrimp, crayfish and crab species pet-traded in the Republic of Kazakhstan, the largest country in this region. Considering computed risk assessment, the origin of particular species, their availability on the market, the probability of establishment and further aspects, we identified two crayfish Procambarus clarkii and Procambarus fallax f. virginalis being the seriously hazardous taxa with high potential to threaten native crayfish species as well as inhabited ecosystems. To prevent their introductions and to minimize the risks of mentioned species, similarly as in the case of European Union, we recommend the total ban of import, trade and keeping of these high-risk taxa within Central Asia.

  1. Cherax quadricarinatus (von Martens has invaded Indonesian territory west of the Wallace Line: evidences from Java

    Directory of Open Access Journals (Sweden)

    Patoka Jiří

    2016-01-01

    Full Text Available Cherax quadricarinatus (von Martens (Decapoda: Astacidea: Parastacidae is commercially exploited and has been intentionally introduced to various tropical and subtropical countries. Once established in the wild, it frequently becomes invasive. In Indonesia, this crayfish is native only to the southern part of the Papua Province. Cherax quadricarinatus is produced in semi-intensive farms for food as well as for ornamental purposes on most of Indonesian territory. We present here the first record of this species from Java, where this crayfish has formed at least two established feral populations. In total, eight subadult and adult crayfish of both sexes were captured in two natural lakes in the city of Bogor, West Java Province. Based on climate match, we suggest that C. quadricarinatus has high potential to become established within most of Indonesian territory. As a rapidly growing species with broad tolerance to varying environmental conditions, its spread is expected and it should be viewed as a possible threat to native decapod crustaceans. Detailed monitoring is therefore needed.

  2. A possible role for the immune system in adult neurogenesis: new insights from an invertebrate model.

    Science.gov (United States)

    Harzsch, Steffen; von Bohlen Und Halbach, Oliver

    2016-04-01

    Persistent neurogenesis in the adult brain of both vertebrates and invertebrates was previously considered to be driven by self-renewing neuronal stem cells of ectodermal origin. Recent findings in an invertebrate model challenge this view and instead provide evidence for a recruitment of neuronal precursors from a non-neuronal source. In the brain of adult crayfish, a neurogenic niche was identified that contributes progeny to the adult central olfactory pathway. The niche may function in attracting cells from the hemolymph and transforming them into cells with a neuronal fate. This finding implies that the first-generation neuronal precursors located in the crayfish neurogenic niche are not self-renewing. Evidence is summarized in support of a critical re-evaluation of long-term self-renewal of mammalian neuronal stem cells. Latest findings suggest that a tight link between the immune system and the system driving adult neurogenesis may not only exist in the crayfish but also in mammals. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Identification of multiple detrital sources for Otway Supergroup sedimentary rocks: implications for basin models and chronostratigraphic correlations

    International Nuclear Information System (INIS)

    Mitchell, M.M.

    1997-01-01

    Correlation of apatite chlorine content (wt%) with apatite fission track age (Ma) from Lower Cretaceous Otway Supergroup sediments at present-day low temperatures, allows identification of two characteristic detrital source regions. Apatites from eroded Palaeozoic basement terrains yield low Cl content (generally 0.5 wt%) and syndepositional fission track ages. Where post-depositional thermal annealing ( > 70 degree C) has significantly reduced the fission track age, provenance information is preserved in the apatite Cl composition alone. In the Otway Supergroup, evidence for contemporaneous volcanism was found in both the Eumeralla Formation (Albian-Aptian), and Crayfish Group (Aptian-Berriasian) in samples located towards the central rift, where less sandy facies dominate. Results suggest that Crayfish Group sediments deposited along the northern margin of the basin were predominantly derived from eroding basement material, while the section located towards the central rift contains a greater proportion of volcanogenic detritus. Evidence from this study suggests that volcanogenic detritus was a distal sediment source throughout the entire early rift phase, prior to the main influx of arc-related volcanogenic material during deposition of the Eumeralla Formation. As diagenesis of volcanogenic sediments significantly reduces porosity and permeability of the sandstones, reservoir quality and petroleum potential may be significantly reduced in the Crayfish Group in deeper parts of the basin where a greater proportion of volcanogenic detritus is suggested. The results presented here provide important information regarding Lower Cretaceous Otway Basin stratigraphy and clearly indicate that this methodology may have wider application. (authors)

  4. How do animals communicate in complex hydrodynamic environments? Linking hydraulics and ecology in rivers.

    Science.gov (United States)

    Johnson, Matthew; Rice, Stephen

    2015-04-01

    Animals make decisions about the suitability of habitat and their reaction to other organisms based on the sensory information that they first obtain from the environment and other organisms within that environment. Sensory information, such as sounds, scents, vibrations and visual cues, is transported, transmitted, masked and filtered by fluvial processes, such as turbulent flow. Despite the fundamental importance of this information in dictating how animals interact with the environment, only limited attention has been paid to the environmental controls on the propagation of sensory signals and cues through fluvial systems. Aquatic animals use and respond to hydraulic characteristics when navigating their environment and selecting habitat. There is evidence that some animals can also sense the presence of other organisms from the hydraulic characteristics of their wake. This implies that at least some aquatic animals can differentiate between the turbulent flow generated by the presence of living organisms and ambient turbulence generated by the environment. We investigate whether there are specific flow characteristics, distinct from the ambient environment, that potentially flag the presence of organisms to other animals. Acoustic Doppler and Particle Image Velocimetry measurements in a series of laboratory flume experiments quantified the flow around living Signal Crayfish (Pacifastacus leniusculus) and two inanimate objects of equivalent shape and size. Experiments were repeated across a gradient of turbulence intensities generated over nine combinations of flow velocity and relative submergence. Flows downstream of living crayfish were distinct from inanimate objects, with greater turbulent intensities, higher energy in low- to intermediate frequencies, and flow structures that were less coherent in comparison to those measured downstream of inanimate objects. However, the hydrodynamic signature of crayfish became masked as the intensity of ambient

  5. Sensory input from the osphradium modulates the response to memory-enhancing stressors in Lymnaea stagnalis.

    Science.gov (United States)

    Karnik, Vikram; Braun, Marvin; Dalesman, Sarah; Lukowiak, Ken

    2012-02-01

    In the freshwater environment species often rely on chemosensory information to modulate behavior. The pond snail, Lymnaea stagnalis, is a model species used to characterize the causal mechanisms of long-term memory (LTM) formation. Chemical stressors including crayfish kairomones and KCl enhance LTM formation (≥24 h) in Lymnaea; however, how these stressors are sensed and the mechanism by which they affect the electrophysiological properties of neurons necessary for memory formation are poorly understood. Here, we assessed whether the osphradium, a primary chemosensory organ in Lymnaea, modulates LTM enhancement. To test this we severed the osphradial nerve proximal to the osphradium, using sham-operated animals as controls, and assessed the behavioral and electrophysiological response to crayfish kairomones and KCl. We operantly conditioned aerial respiratory behavior in intact, sham and osphradially cut animals, and tested for enhanced memory formation after exposure to the chemical stressors. Sham-operated animals displayed the same memory enhancement as intact animals but snails with a severed osphradial nerve did not show LTM enhancement. Extracellular recordings made from the osphradial nerve demonstrate that these stressors evoked afferent sensory activity. Intracellular recordings from right pedal dorsal 1 (RPeD1), a neuron necessary for LTM formation, demonstrate that its electrophysiological activity is altered by input from the osphradium following exposure to crayfish kairomones or KCl in sham and intact animals but no response is seen in RPeD1 in osphradially cut animals. Therefore, sensory input from the osphradium is necessary for LTM enhancement following exposure to these chemical stressors.

  6. Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

    Directory of Open Access Journals (Sweden)

    Chadanat Noonin

    Full Text Available Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS, bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish and Tenebrio molitor larvae (mealworm. The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the

  7. Melanization and Pathogenicity in the Insect, Tenebrio molitor, and the Crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3

    Science.gov (United States)

    Noonin, Chadanat; Jiravanichpaisal, Pikul; Söderhäll, Irene; Merino, Susana; Tomás, Juan M.; Söderhäll, Kenneth

    2010-01-01

    Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS), bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish) and Tenebrio molitor larvae (mealworm). The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core) is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT) containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the proPO system

  8. Fixation and long-term accumulation of tritium from tritiated water in an experimental aquatic environment

    International Nuclear Information System (INIS)

    Strand, J.A.; Templeton, W.L.; Olson, P.A.

    1975-01-01

    The accumulation of tritium in selected freshwater biota was studied in a 10 m diameter concrete-lined pond at the Hanford Atomic Energy Works. Tritium as tritiated water was introduced for 8 months continuously in the replacement water at a concentration of μCi per liter; and water, biota (carp, clams, crayfish, periphyton, pondweed), and sediments were sampled on a predetermined schedule. The pond was maintained on uncontaminated replacement waters for an additional 8 months to determine the rate of elimination from the ecosystem. After the first day, tissue-free-water tritium in all biota approached an equilibrium with pond water. Final concentration factors of 0.89, 0.87, 0.82, 0.92, 0.77, 0.88 were calculated for carp, clam, crayfish, snail, periphyton, and pondweed. Although highly variable, analyses of pond sediments suggested an initial rapid uptake by the loose water fraction, attaining 0.30 of the pond equilibrium level in three days. There was evidence to suggest a secondary slower rate of uptake that accounted for 0.65 of the pond equilibrium level as determined at seven months. Tissue-bond tritium initially increased rapidly in all biota sampled, but slowed with time. Equilibrium conditions were not reached. Final concentration factors for carp, clam, crayfish, snail, periphyton, and pondweed were calculated to be 0.49, 0.10, 0.53, 0.54, 0.15, and 0.62. Analyses of sediments after removal of the loose water fraction revealed little or no organically bound tritium

  9. Effects of sublethal exposure to lead on levels of energetic compounds in Procambarus clarkii (Girard, 1852)

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M.; Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

    1994-05-01

    Lead is neither essential nor beneficial to living organisms; all existing data show that its metabolic effects are adverse. Lead is toxic to all phyla of aquatic biota. Most of the lead discharged into surface water is rapidly incorporated into suspended and bottom sediments. The American red crayfish, Procambarus clarkii, lives in a wide range of environmental conditions that include highly polluted waters. Lead present in take sediments can be available to aquatic animals such as P. clarkii because it is a detritivor and burrow into the sediment. In fact, we found remarkable levels of lead in tissues of P. clarkii caught in Albufera Lake and kept 15 days in clean water (e. g. 223 [mu]g/g dry weight in gills). Furthermore, P. clarkii has a high capacity for lead accumulation from water, and gills were the most important tissue of lead accumulation. Among effects that contaminants have on the physiology of the organisms, energetic state variables are important, since they will alter both survival and reproduction. Hepatopancreas is a major site for the energetic reserve in crayfish and is a site of lead accumulation, although metal concentration in this organ is not as high as gills. The purpose of this study was to examine changes in energy reserves in hepatopancreas and gills of the crayfish P. clarkii, in response to sublethal exposure to lead. Gills are directly exposed to contaminants in the environment, and they are the first organ showing alterations by the action of the contaminants. Hepatopancreas was also chosen due to both, its relevance in the energetic metabolism and its role in heavy metal detoxification mechanisms.

  10. Marcellus and mercury: Assessing potential impacts of unconventional natural gas extraction on aquatic ecosystems in northwestern Pennsylvania.

    Science.gov (United States)

    Grant, Christopher J; Weimer, Alexander B; Marks, Nicole K; Perow, Elliott S; Oster, Jacob M; Brubaker, Kristen M; Trexler, Ryan V; Solomon, Caroline M; Lamendella, Regina

    2015-01-01

    Mercury (Hg) is a persistent element in the environment that has the ability to bioaccumulate and biomagnify up the food chain with potentially harmful effects on ecosystems and human health. Twenty-four streams remotely located in forested watersheds in northwestern PA containing naturally reproducing Salvelinus fontinalis (brook trout), were targeted to gain a better understanding of how Marcellus shale natural gas exploration may be impacting water quality, aquatic biodiversity, and Hg bioaccumulation in aquatic ecosystems. During the summer of 2012, stream water, stream bed sediments, aquatic mosses, macroinvertebrates, crayfish, brook trout, and microbial samples were collected. All streams either had experienced hydraulic fracturing (fracked, n = 14) or not yet experienced hydraulic fracturing (non-fracked, n = 10) within their watersheds at the time of sampling. Analysis of watershed characteristics (GIS) for fracked vs non-fracked sites showed no significant differences (P > 0.05), justifying comparisons between groups. Results showed significantly higher dissolved total mercury (FTHg) in stream water (P = 0.007), lower pH (P = 0.033), and higher dissolved organic matter (P = 0.001) at fracked sites. Total mercury (THg) concentrations in crayfish (P = 0.01), macroinvertebrates (P = 0.089), and predatory macroinvertebrates (P = 0.039) were observed to be higher for fracked sites. A number of positive correlations between amount of well pads within a watershed and THg in crayfish (r = 0.76, P macroinvertebrates (r = 0.71, P water microbial communities within the Deltaproteobacteria also shared a positive correlation with FTHg and to the number of well pads, while stream pH (r = -0.71, P macroinvertebrate taxa richness (r = -0.60, P = 0.01) were negatively correlated with the number of well pads within a watershed. Further investigation is needed to better elucidate relationships and pathways of observed differences in stream water chemistry, biodiversity, and

  11. Paragonimus westermani infection in lung: A confounding diagnostic entity

    Directory of Open Access Journals (Sweden)

    Shivani Kalhan

    2015-01-01

    Full Text Available Paragonimiasis is a food-borne parasitic zoonosis caused by the genus Paragonimus. Fresh water snails, crabs, and crayfish are the first and second intermediate hosts, respectively. Humans acquire this infection by ingesting uncooked/undercooked crustaceans. Laboratory diagnosis of Paragonimiasis is done by demonstration of ova in the sputum/feces/pleural fluid or by serology. A case of pulmonary Paragonimiasis is presented herewith; the patient having been diagnosed with pulmonary tuberculosis earlier. The aim of this presentation is to highlight this entity so that it is considered in the differential diagnosis in a case of hemoptysis.

  12. Prevalence and intensity of Paragonimus uterobilateralis infection among school children in Oban village, South Eastern, Nigeria.

    Science.gov (United States)

    Ochigbo, S O; Ekanem, E E; Udo, J J

    2007-10-01

    A survey of Paragonimus infection among primary school children aged 6-10 years in Oban village, Akamkpa Local Government Area of Cross River State, Nigeria, was conducted. A total of 198 children were examined:112 (56.6%) were boys while 86 (43.4%) were girls. Eleven of the subjects were sputum positive for paragonimus eggs, giving an overall prevalence rate of 5.5%. The findings show that paragonimiasis is a significant health problem in South Eastern Nigeria; the risk of infection could be minimized by the proper cooking of fresh water crabs and crayfish before consumption.

  13. Neuroprotective effects of Lepidium meyenii (Maca).

    Science.gov (United States)

    Pino-Figueroa, Alejandro; Nguyen, Diane; Maher, Timothy J

    2010-06-01

    The neuroprotective activity of the plant Lepidium meyenii (Maca) was studied in two experimental models: in vitro and in vivo. Crayfish neurons were pretreated with vehicle or the pentane extract from Maca, subjected to H(2)O(2), and their viability determined microscopically and chemically. A significant concentration-neuroprotective effect relationship was demonstrated. The pentane extract was then administered intravenously to rats prior to and following middle cerebral artery occlusion. While infarct volumes were decreased for the lower dose, higher doses increased infarct volumes compared to controls. These results suggest a potential application of Maca as a neuroprotectant.

  14. Malignant melanoma and other cancers of the skin in Czech Republic (epidemiology, risk factors and prevention possibilities).

    OpenAIRE

    Pojezná, Eliška

    2009-01-01

    two basic types: non-melanoma skin cancer and melanoma. Skin tumors mean up to 5%. The increase in incidence is due to both a strong knowledge ofdevelopment issues and melanoma tumor detection and efforts to reduce its incidence. Also in the diagnosis of melanoma was diagnosis. Although in recent years to s tumor. I see a reduction in its incidence. Also in the diagnostic result in death, but are far from melanoma malignancy. This does not mean that they should vykousanou crayfish or crab. "i...

  15. Inferring fixed effects in a mixed linear model from an integrated likelihood

    DEFF Research Database (Denmark)

    Gianola, Daniel; Sorensen, Daniel

    2008-01-01

    A new method for likelihood-based inference of fixed effects in mixed linear models, with variance components treated as nuisance parameters, is presented. The method uses uniform-integration of the likelihood; the implementation employs the expectation-maximization (EM) algorithm for elimination...... of all nuisances, viewing random effects and variance components as missing data. In a simulation of a grazing trial, the procedure was compared with four widely used estimators of fixed effects in mixed models, and found to be competitive. An analysis of body weight in freshwater crayfish was conducted...

  16. Physical data and biological data for algae, aquatic invertebrates, and fish from selected reaches on the Carson and Truckee rivers, Nevada and California, 1993-97

    Science.gov (United States)

    Lawrence, S.J.; Seiler, R.L.

    2002-01-01

    This report, a product of the National Water- Quality Assessment Program, is a compilation of physical data and biological data for algae, aquatic invertebrates, and fish collected in the Carson and Truckee River Basins, Nevada and California. Most of the data were collected between 1993 and 1996 at selected reaches on the Carson and Truckee Rivers. Algae and aquatic invertebrate samples were collected from cobble riffles, submerged woody-snag habitats, and from depositional areas such as pools. Between 1993 and 1996, fish and crayfish were collected from all wadeable habitats at each of seven basic-fixed sites using either electroshocking methods or seining. Additional fish and crayfish were collected at one site on the Truckee River in 1997. Fish were identified to species, measured for total and standard length, checked for anomalies, and weighed at the collection site. Fish were returned to the stream after measurements were taken. Measurements of water depth, stream velocity, determinations of substrate type and substrate embeddedness were made at each sampling site. Algae and aquatic invertebrate samples were sent to the U.S. Geological Survey National Water-Quality Laboratory for identification and enumeration. A total of 103 semi-quantitative and 55 qualitative algae samples were collected at 20 river reaches on the Carson and Truckee Rivers between 1993 and 1996. These samples represent algae in cobble riffles, on submerged woody snags, and on sediment surfaces in depositional areas. In those 158 samples, 514 algal species, varieties, or forms were identified. Of the 8 algal phyla represented, the diatoms (Phylum Bacillariophyta) were the most abundant with 351 species, varieties, or forms. The green algae (Phylum Chlorophyta) were next in abundance with 108 species, varieties, or forms followed by the blue-green algae (Phylum Cyanophyta) with 41 species, varieties, or forms. A total of 49 semi-quantitative aquatic invertebrate samples were collected at 27

  17. Aquaculture at Oregon Inst. of Technology

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, B.

    1976-07-01

    The geothermal hot water resource developed from on-campus wells is used for space heating and heating the college's potable hot water supply. The development of this resource has provided waste water for aquaculture. The available water for aquaculture is a volume of 200 to 250 gal/min with a mean temperature of 57/sup 0/C. This water was tested on mosquitofish, guppies, and crayfish. A program is now underway to see if the giant freshwater prawn may be grown commercially in geothermal waste water. (MHR)

  18. Growth, Survival and Spore Formation of the Pathogenic Aquatic Oomycete Aphanomyces astaci and Fungus Fusarium avenaceum Are Inhibited by Zanthoxylum rhoifolium Bark Extracts In Vitro

    Directory of Open Access Journals (Sweden)

    Caterina Pagliarulo

    2018-02-01

    Full Text Available This study aimed to evaluate the in vitro activity of Zanthoxylum rhoifolium bark (Zr-b extracts against pathogenic aquatic oomycete/fungal isolates that cause different diseases in native European crayfish resulting in an elevated mortality rate and severe economic repercussions. n-hexane, chloroform, chloroform–methanol (9:1 and methanol extracts of Zr-b were used to evaluate the antifungal activity against the strain UEF88662 of Aphanomyces astaci (oomycete and the strain SMM2 of Fusarium avenaceum (fungus. The anti-oomycete and antifungal activity was quantitatively evaluated by growth, survival and sporulation microbiological assays. The extracts tested demonstrated a dose-dependent inhibitory effect on oomycete and fungal growth and survival, as well as on the production of oomycete and fungal spores. This work presents alternatives for the treatment and prevention of the spreading of Aphanomyces astaci and Fusarium avenaceum, the etiological agents of the diseases crayfish plague and brown spot disease, respectively. The antifungal properties of Zanthoxylum rhoifolium bark extracts warrant further research on their use in the prevention and treatment of both oomycete and fungal diseases. The antifungal properties of Zanthoxylum rhoifolium bark extracts, shown in vitro, indicate the possibility of their use in new therapeutic and prophylactic strategies, providing perspectives for the design of in vivo studies.

  19. GYRKPPFNGSIFamide (Gly-SIFamide) Modulates Aggression in the Freshwater Prawn Macrobrachium rosenbergii

    Science.gov (United States)

    Vázquez-Acevedo, Nietzell; Rivera, Nilsa M.; Torres-González, Alejandra M.; Rullan-Matheu, Yarely; Ruíz-Rodríguez, Eduardo A.; Sosa, María A.

    2010-01-01

    The freshwater prawn Macrobrachium rosenbergii is a tropical crustacean with characteristics similar to those of lobsters and crayfish. Adult males develop through three morphological types—small (SC), yellow (YC), and blue claws (BC)—with each representing a level in the dominance hierarchy of a group, BC males being the most dominant. We are interested in understanding the role played by neuropeptides in the mechanisms underlying aggressive behavior and the establishment of dominance hierarchies in this type of prawn. SIFamides are a family of arthropod peptides recently identified in the central nervous system of insects and crustaceans, where it has been linked to olfaction, sexual behavior, and gut endocrine functions. One of the six SIFamide isoforms, GYRKPPFNGSIFamide (Gly-SIFamide), is highly conserved among decapod crustaceans such as crabs and crayfish. We wanted to determine whether Gly-SIFamide plays a role in modulating aggression and dominant behavior in the prawn. To do this, we performed behavioral experiments in which interactions between BC/YC pairs were recorded and quantified before and after injecting Gly-SIFamide directly into the circulating hemolymph of the living animal. Behavioral data showed that aggression among interacting BC/YC prawns was enhanced by injection of Gly-SIFamide, suggesting that this neuropeptide does have a modulatory role for this type of behavior in the prawn. PMID:20040755

  20. Sensitive and rapid detection of Paragonimus westermani infection in humans and animals by loop-mediated isothermal amplification (LAMP).

    Science.gov (United States)

    Chen, M X; Ai, L; Zhang, R L; Xia, J J; Wang, K; Chen, S H; Zhang, Y N; Xu, M J; Li, X; Zhu, X Q; Chen, J X

    2011-05-01

    In the present study, a loop-mediated isothermal amplification (LAMP) assay was developed and validated for the detection of Paragonimus westermani adults, metacercariae, and eggs in human and animal samples. The LAMP amplification can be finished in 45 min under isothermal condition at 60°C by employing a set of four species-specific primer mixtures and the results can be checked by naked-eye visualization. No amplification products were detected with deoxyribunucleic acid (DNA) of related trematode species including Fasciola hepatica, Fasciola gigantica, Clonorchis sinensis, Opisthorchis viverrini, Schistosoma mansoni, and Schistosoma japonicum. The method was further validated by examining P. westermani DNA in intermediate hosts including freshwater crabs and crayfish, as well as in sputum and pleural fluid samples from patients of paragonimiasis. These results indicated that the LAMP assay was highly specific, sensitive, and rapid, and it was approximately 100 times more sensitive than conventional specific PCR. The LAMP assay established in this study provides a rapid and sensitive tool for the detection of P. westermani DNA in freshwater crabs, crayfish, sputum, and pleural fluid samples, which has important implications for effective control of human paragonimiasis.

  1. Potential use of power plant reject heat in commercial aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10/sup 5/ kg/year of fish, 1.5 x 10/sup 6/ kg/year of clam meat, and 1.5 x 10/sup 4/ kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated.

  2. Biological control of snail hosts transmitting schistosomiasis by the water bug, Sphaerodema urinator.

    Science.gov (United States)

    Younes, Aly; El-Sherief, Hanaa; Gawish, Fathia; Mahmoud, Marwa

    2017-04-01

    The water bug, Sphaerodema urinator (Hemiptera : Belostomatidae), shares the same habitat of the freshwater snails in ponds, lakes, and streams. Studies conducted in lakes show that fish and crayfish predators play an important role in determining the abundance of freshwater snails. In contrast, shallow ponds and marches often lack fish and crayfish but have abundant insect predators. This study has been carried out to evaluate the predatory potential of S. urinator adult on two freshwater snails that serves as intermediate hosts of Schistosoma. Laboratory evaluation of predation by S. urinator on these intermediate hosts revealed that the adult bug could kill and consume the two intermediate hosts: Bulinus truncatus and Biomphalaria alexandrina. The number of snails consumed differed according to the snail type, size, and density. The times taken for searching and handling times were depending on the snail size, type, and vulnerability of the predator. The predation rate varied also with respect to snail type and density. Prey size is a major factor influencing predator preferences. This study indicated that the predator, S. urinator, may be a suitable bio-control agent in connection with Schistosoma intermediate hosts in the aquatic area.

  3. A pilot study testing a natural and a synthetic Molluscicide for controlling invasive apple snails (Pomacea maculata)

    Science.gov (United States)

    Olivier, Heather M.; Jenkins, Jill A.; Berhow, Mark; Carter, Jacoby

    2016-01-01

    Pomacea maculata (formerly P. insularum), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea (Camellia sinensis) seed derivative (TSD) or niclosamide monohydrate (Pestanal®, 2′,5-dichloro-4′-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish (Procambarus clarkii) and redear sunfish (Lepomis microlophus). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).

  4. Spatial and temporal variations of mercury levels in Okefenokee invertebrates: Southeast Georgia

    International Nuclear Information System (INIS)

    George, Bagie M.; Batzer, Darold

    2008-01-01

    Accumulation of mercury in wetland ecosystems has raised concerns about impacts on wetland food webs. This study measured concentrations of mercury in invertebrates of the Okefenokee Swamp in Georgia, focusing on levels in amphipods, odonates, and crayfish. We collected and analyzed total mercury levels in these invertebrates from 32 sampling stations across commonly occurring sub-habitats. Sampling was conducted in December, May, and August over a two-year period. The highest levels of mercury were detected in amphipods, with total mercury levels often in excess of 20 ppm. Bioaccumulation pathways of mercury in invertebrates of the Okefenokee are probably complex; despite being larger and higher in the food chain, levels in odonates and crayfish were much lower than in amphipods. Mercury levels in invertebrates varied temporally with the highest levels detected in May. There was a lack of spatial variation in mercury levels which is consistent with aerial deposition of mercury. - This study measured mercury levels in invertebrates and found the highest levels in amphipods

  5. Is the Sacred ibis a real threat to biodiversity? Long-term study of its diet in non-native areas compared to native areas.

    Science.gov (United States)

    Marion, Loïc

    2013-04-01

    This paper presents the results of a 14-year study about the diet of the Sacred ibis in its main introduction area in France and its impact on native bird species, and compares the data to literature from its native area. During an initial period (1993-2004), the diet was essentially composed of invertebrates such as common aquatic insects (correlated with flooding) or Eristalis larvae picked from the mud (a vacant food niche in France), while scraps of meat taken from rubbish dumps were minor. These traditional preys taken from the same ecosystems as in its native area did not result in an exponential increase of the number of breeding Sacred ibises. Invasive Red swamp crayfish recently replaced other foods in its diet with a resulting sharp increase in breeding pair numbers (R(2)=0.48). As in other parts of the world, vertebrates constituted very accidental preys, and no bird species were really threatened by such predation. Conversely, the Sacred ibis can have a positive effect as a predator of invasive crayfish. Adding the species to the DAISIE list of the 100 most invasive alien species in Europe therefore appears debatable. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  6. Invasive Species Mediate Insecticide Effects on Community and Ecosystem Functioning.

    Science.gov (United States)

    Rodrigues, Andreia C M; Machado, Ana L; Bordalo, Maria D; Saro, Liliana; Simão, Fátima C P; Rocha, Rui J M; Golovko, Oksana; Žlábek, Vladimír; Barata, Carlos; Soares, Amadeu M V M; Pestana, João L T

    2018-04-03

    Anthropogenic activities increase pesticide contamination and biological invasions in freshwater ecosystems. Understanding their combined effects on community structure and on ecosystem functioning presents challenges for an improved ecological risk assessment. This study focuses on an artificial stream mesocosms experiment testing for direct and indirect effects of insecticide (chlorantraniliprole - CAP) exposure on the structure of a benthic macroinvertebrate freshwater community and on ecosystem functioning (leaf decomposition, primary production). To understand how predator identity and resource quality alter the community responses to chemical stress, the mediating effects of an invasive predator species (crayfish Procambarus clarkii) and detritus quality (tested by using leaves of the invasive Eucalyptus globulus) on insecticide toxicity were also investigated. Low concentrations of CAP reduced the abundance of shredders and grazers, decreasing leaf decomposition and increasing primary production. Replacement of autochthonous predators and leaf litter by invasive species decreased macroinvertebrate survival, reduced leaf decomposition, and enhanced primary production. Structural equation modeling (SEM) highlighted that CAP toxicity to macroinvertebrates was mediated by the presence of crayfish or eucalypt leaf litter which are now common in many Mediterranean freshwaters. In summary, our results demonstrate that the presence of these two invasive species alters the effects of insecticide exposure on benthic freshwater communities. The approach used here also allowed for a mechanistic evaluation of indirect effects of these stressors and of their interaction on ecosystem functional endpoint, emphasizing the value of incorporating biotic stressors in ecotoxicological experiments.

  7. YEAR CYCLE OF AUSTROPOTAMOBIUS TORRENTIUM (SCHRANK IN STREAMS ON MEDVEDNICA MOUNTAIN (CROATIA.

    Directory of Open Access Journals (Sweden)

    MAGUIRE I.

    2002-07-01

    Full Text Available We studied life cycle of stone crayfish for 18 months in three streams on Medvednica Mountain, located above city of Zagreb. Sampling of animals was carried out with baited traps twice a month and various physiological functions were recorded. Sex ratio of trapped crayfish was 1:1, but it fluctuated during the year. Animals were active from early spring until the beginning of November when their activities significantly decreased. In this period we noticed three peaks of higher activity. The first one after winter starvation in March, the second one after egg hatching (June/July and the third one during mating period (end of September - beginning of November. The maximal recorded weight for female was 38 g while the heaviest male was 55 g. The longest female was 9.28 cm and male 10.30 cm. Development of glair glands started from the end of July, mating occurred at the end of October and the juveniles hatched until mid-June. Freshly moulted animals were found from mid-May until mid-October. Main injuries were claw and limb loss. We noticed the presence of burn spot disease and Branchiobdella parasita Henle within studied populations. Correlation with five different physico-chemical parameters of water showed that animals’ activity is positively correlated to water temperature, conductivity, pH and hardness and negatively to oxygen concentration.

  8. Potential use of power plant reject heat in commercial aquaculture

    International Nuclear Information System (INIS)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10 5 kg/year of fish, 1.5 x 10 6 kg/year of clam meat, and 1.5 x 10 4 kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated

  9. A Pilot Study Testing a Natural and a Synthetic Molluscicide for Controlling Invasive Apple Snails (Pomacea maculata).

    Science.gov (United States)

    Olivier, Heather M; Jenkins, Jill A; Berhow, Mark; Carter, Jacoby

    2016-03-01

    Pomacea maculata (formerly P. insularum), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea (Camellia sinensis) seed derivative (TSD) or niclosamide monohydrate (Pestanal(®), 2',5-dichloro-4'-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish (Procambarus clarkii) and redear sunfish (Lepomis microlophus). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).

  10. Life History Variation in Invading Applesnails (Pomacea canaliculata) May Pose Ecological Threats to Wetlands

    Science.gov (United States)

    Marfurt, R. K.; Boland, B. B.; Burks, R. L.

    2005-05-01

    In native habitats, channeled applesnails (Pomacea canaliculata) graze periphyton. However, casual observations from introduced populations suggest these invaders show variation in feeding ecology, predator response and life history strategies. Attempts to predict this consumer influence on ecosystem function suffer from a lack of basic data. We tested how salinity affected snail mortality. Both adults and hatchlings tolerated salinity levels up to 8 ppt. Adult feeding on lettuce increased significantly at 8 ppt compared to 0 ppt (p = 0.002), while hatchling consumption of algae did not vary (p = 0.284). To see how these consumers responded to predators from the invaded ecosystem, we tested behavioural responses to predatory cues from fish, turtles, crayfish and adult applesnails. Results indicated that fish and crayfish prompted similar predator-avoidance behaviors in hatchlings (p's 0.05) between native (ramshorn) and exotic applesnails, whereas adult fish consumed more applesnails (x2, p < 0.001). Our current efforts focus on examining if predator presence or macrophyte choice alters applesnail feeding rates. Research providing insight into the basic ecology of applesnails can foster management efforts at the ecosystem scale.

  11. Gill ATPase activity in Procambarus clarkii as an indicator of heavy metal pollution

    Energy Technology Data Exchange (ETDEWEB)

    Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

    1989-06-01

    Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues, including heavy metals, from the many urban and waste waters of this area. The American red crayfish, Procambarus clarkii have a high resistance to toxic effects of heavy metals. The sublethal effects of heavy metals on gills of fish and aquatic invertebrates have been extensively studied. Some metabolic disturbances and histologic damages have been reported, as well as osmoregulation alterations. However, little work has been done about the effect of heavy metals on Na,K and Mg-ATPases of freshwater invertebrate gills. Na,K-ATPase is the prime mediator of ion transport across cellular membranes and plays a central role in whole body ion regulation in marine and estuarine animals. Na,K-ATPase has been reviewed and assessed as a potentially useful indicator of pollution stress in aquatic animals. The purpose of this study is look for the relation, if any, between crayfish gill ATP-ase activity changes and metal exposure in laboratory. This find would allow the authors to assay this potential indicator in the field.

  12. Revisiting reproduction and population structure and dynamics of Procambarus clarkii eight years after its introduction into Lake Trasimeno (Central Italy

    Directory of Open Access Journals (Sweden)

    Dörr A.J.M.

    2013-06-01

    Full Text Available Understanding population dynamics and regulation is fundamental for predicting establishment and spread of invasive alien species. In addition, the population biology of invasive alien species offers an opportunity to study basic ecological processes. In this context, we investigated reproductive and growth plasticity in the invasive crayfish Procambarus clarkii in Lake Trasimeno (central Italy. In total, 3153 crayfish were collected monthly from June 2007 to July 2009. The molt status was assessed by evaluating the exoskeleton hardness. To assess the reproductive cycle, the gonado-somatic and wet hepato-somatic indices were calculated for females. The reproductive status of males was appraised as well. We estimated growth and longevity using the von Bertalanffy growth function, and calculated the total, natural and fishing mortality indices. We then compared our present data with those obtained from the same population eight years before. Our results indicate some changes in population dynamics and in both molting and reproductive periods since the initial invasion of the shallow lake investigated. Long-term differences in the life history of the Trasimeno population may be the result of selective pressures different from those of the native range, but may also result from colonization events and human interference caused by professional fishing activities.

  13. Development of Ecogeomorphological (EGM Stream Design and Assessment Tools for the Piedmont of Alabama, USA

    Directory of Open Access Journals (Sweden)

    Brian Helms

    2016-04-01

    Full Text Available Regional data needed for effective stream restoration include hydraulic geometry relationships (i.e., regional curves and reference channel morphology parameters. Increasingly ecological conditions are being considered when designing, implementing, and assessing restoration efforts. We provide morphology relationships and associated ecological endpoint curves for reference streams in the Alabama piedmont. Twenty-one reference stream reaches were identified in the Tallapoosa drainage of Alabama, ranging from 0.2 to 242 km2 drainage area. Geomorphic surveys were conducted in each stream to measure riffle cross-sections and longitudinal profiles and related to drainage area to develop regional curves. Fish, crayfish, and benthic macroinvertebrates were collected from each surveyed reach and related to drainage area and geomorphic data to provide associated biological community endpoints. Bankfull channel cross-section area, width, mean depth, and estimated discharge were strongly correlated to watershed drainage area, similar to efforts in other areas of the Piedmont ecoregion. Multiple measures of fish assemblages and crayfish size were strongly predicted by drainage area and geomorphic dimensions. Macroinvertebrates showed no taxonomic and limited functional relationships with drainage area and geomorphic dimension. These tools, which integrate geomorphological and ecological conditions, can result in improved stream evaluations and designs increasing the effectiveness of stream restoration projects.

  14. Seeing orange: prawns tap into a pre-existing sensory bias of the Trinidadian guppy

    Science.gov (United States)

    De Serrano, Alexandra R.; Weadick, Cameron J.; Price, Anna C.; Rodd, F. Helen

    2012-01-01

    Sensory bias, a predisposition towards certain signals, has been implicated in the origin of mate preferences in some species. A risk associated with these biases is that they can be co-opted by predators as sensory lures. Here we propose that the orange spots on the brown pincers of a diurnal, predatory species of prawn function as lures for Trinidadian guppies, which have a sensory bias for orange. We exposed female guppies to (i) a life-like model of this Trinidadian prawn with orange, green or no spots on the pincers or (ii) a live, novel (non-Trinidadian) crustacean (crayfish), also with spotted pincers. First, we provide evidence that guppies sympatric with the prawn recognized our model as a potential predator. Next, we found that guppies spent more time in the dangerous head region of the model prawn with orange-spotted pincers compared with unspotted pincers. Finally, we show that allopatric, but not sympatric, guppies spent more time in the vicinity of the head of a live crayfish when orange spots were added to its pincers than when brown spots were added. Our results suggest that the orange spots on prawn pincers can act as a sensory lure. PMID:22593111

  15. 2D-DIGE as a proteomic biomarker discovery tool in environmental studies with Procambarus clarkii.

    Science.gov (United States)

    Fernández-Cisnal, Ricardo; García-Sevillano, Miguel A; Gómez-Ariza, José L; Pueyo, Carmen; López-Barea, Juan; Abril, Nieves

    2017-04-15

    A 2D-DIGE/MS approach was used to assess protein abundance differences in the red swamp crayfish Procambarus clarkii from polluted aquatic ecosystems of Doñana National Park and surrounding areas with different pollution loads. Procambarus clarkii accumulated metals in the digestive glands and gills reflecting sediment concentrations. We first stated that, probably related to elements accumulation, pollution increased oxidative damage in P. clarkii tissues, as shown by the thiol oxidation status of proteins and MDA levels. In these animals, the altered redox status might be responsible for the deregulated abundance of proteins involved in cellular responses to oxidative stress including protein folding, mitochondrial imbalance and inflammatory processes. Interestingly, polluted P. clarkii crayfish also displayed a metabolic shift to enhanced aerobic glycolysis, most likely aimed at generating ATP and reduction equivalents in an oxidative stress situation that alters mitochondrial integrity. The deregulated proteins define the physiological processes affected by pollutants in DNP and its surrounding areas and may help us to unravel the molecular mechanisms underlying the toxicity of environmental pollutants. In addition, these proteins might be used as exposure biomarkers in environmental risk assessment. The results obtained might be extrapolated to many other locations all over the world and have the added value of providing information about the molecular responses of this environmentally and economically interesting animal. Metal content in digestive gland and gills of P. clarkii crayfish reflects their contents in sediments at sites of Doñana National Park and its surroundings. Accumulation of essential and toxic transition metals is paralleled by clear signs of oxidative stress to lipids and proteins and by significant deregulation of many proteins involved in protein folding, mitochondrial respiratory imbalance and inflammatory response. These results

  16. Effects of serotonin and fluoxetine on blood glucose regulation in two decapod species

    Directory of Open Access Journals (Sweden)

    Santos E.A.

    2001-01-01

    Full Text Available One of the best known crustacean hormones is the crustacean hyperglycemic hormone (CHH. However, the mechanisms involved in hormone release in these animals are poorly understood, and thus constitute the central objective of the present study. Different groups of crustaceans belonging to diverse taxa (Chasmagnathus granulata, a grapsid crab and Orconectes limosus, an astacid were injected with serotonin, fluoxetine, or a mixture of both, and glycemic values (C. granulata and O. limosus and CHH levels (O. limosus were determined after 2 h in either submerged animals or animals exposed to atmospheric air. Both serotonin and fluoxetine caused significant hyperglycemia (P<0.05 after injection into the blood sinus of the two species, an effect enhanced after exposure to atmospheric air. In C. granulata blood glucose increased from 6.1 to 43.3 and 11.4 mg/100 ml in submerged animals and from 5.7 to 55.2 and 22.5 mg/100 ml in air-exposed animals after treatment with serotonin and fluoxetine, respectively. In O. limosus the increases were from 1.2 to 59.7 and 135.2 mg/100 ml in submerged animals and from 2.5 to 200.3 and 193.6 mg/100 ml in air-exposed animals after treatment with serotonin and fluoxetine, respectively. Serotonin and fluoxetine also caused a significant increase in the circulating levels of CHH in O. limosus, from 11.9 to 43 and 45.7 fmol/ml in submerged animals and from 13.2 to 32.6 and 45.7 fmol/ml in air-exposed animals, respectively, thus confirming their action as neuroregulators in these invertebrates.

  17. Simultaneous determination of UV-filters and estrogens in aquatic invertebrates by modified quick, easy, cheap, effective, rugged, and safe extraction and liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    He, Ke; Timm, Anne; Blaney, Lee

    2017-08-04

    Ultraviolet-filters (UV-filters) and estrogens have attracted increased attention as contaminants of emerging concern (CECs) due to their widespread occurrence in the environment. Most of these CECs are hydrophobic and have the potential to accumulate in aquatic organisms. To date, co-analysis of UV-filters and estrogens has not been reported due, in part, to the complex environmental matrices. Here, a multi-residue method has been developed for simultaneous determination of five UV-filters and three estrogens in tissue from aquatic and marine organisms. The procedure involved a modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction with a novel reverse-solid-phase extraction (reverse-SPE) cleanup in place of dispersive-SPE, followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. The tissue mass, acetonitrile content, and salt conditions for QuEChERS extraction, along with the reverse-SPE cartridge material and elution conditions, were thoroughly investigated and optimized. Five UV-filters (i.e., 3-(4-methylbenzylidene) camphor, benzophenone-3, ethylhexylmethoxycinnamate, homosalate, and octocrylene) and three estrogens (i.e., estrone, 17β-estradiol, and 17α-ethinylestradiol) were simultaneously analyzed by taking advantage of wrong-way-round ionization in LC-MS/MS. The optimized analytical protocol exhibited good recoveries (>80%) for target compounds and enabled their detection at concentrations as low as 0.2ng/g in 50mg tissue samples. The method was applied to determine concentrations of target analytes in four invertebrates (i.e., Orconectes virilis, Procambarus clarkii, Crassostrea virginica, and Ischadium recurvum). All eight target analytes were detected at least once in the tissue samples, with the highest concentration being 399ng/g of homosalate in O. virilis. These results highlight the ubiquitous bioaccumulation of CECs in aquatic and marine invertebrates. Copyright © 2017 Elsevier B.V. All rights

  18. Actinide elements in aquatic and terrestrial environments

    International Nuclear Information System (INIS)

    Bondietti, E.A.

    1978-01-01

    Progress is reported in terrestrial ecology studies with regard to plutonium in biota from the White Oak Creek forest; comparative distribution of plutonium in two forest ecosystems; an ecosystem model of plutonium dynamics; actinide element metabolism in cotton rats; and crayfish studies. Progress is reported in aquatic studies with regard to transuranics in surface waters, frogs, benthic algae, and invertebrates from pond 3513; and radioecology of transuranic elements in cotton rats bordering waste pond 3513. Progress is also reported in stability of trivalent plutonium in White Oak Lake water; chemistry of plutonium, americium, curium, and uranium in pond water; uranium, thorium, and plutonium in small mammals; and effect of soil pretreatment on the distribution of plutonium

  19. Annual report of ecological research at the Savannah River Ecology Laboratory

    International Nuclear Information System (INIS)

    1976-05-01

    Studies on mineral cycling are concerned with availability of stable elements and radionuclides to the biota of the southeastern coastal plain; the role of primary producers, consumers, and detritivores in cycling processes; the factors that limit or regulate rate processes in southeastern ecosystems; the importance of interactions among energy flow, thermal environments, and mineral cycling processes on rates of biomass buildup and transfer within southeastern ecosystems; the extent to which transfer coefficients are modified by population processes that influence the temporal or spatial turnover of compartmental standing crops; and the validation of models of cycling processes in southeastern ecosystems at various sites on the southeastern coastal plain. Research in thermal ecology is being conducted on macrophytes, snails, fishes, high parasites, shrimp, crayfish, turtles, and alligators

  20. Chronic toxicity of contaminated sediments on reproduction and histopathology of the crustacean Gammarus fossarum and relationship with the chemical contamination and in vitro effects

    Energy Technology Data Exchange (ETDEWEB)

    Mazurova, Edita; Hilscherova, Klara; Sidlova-Stepankova, Tereza; Blaha, Ludek [Faculty of Science, RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk Univ., Brno (Czech Republic); Koehler, Heinz R. [Animal Physiological Ecology, Univ. of Tuebingen (Germany); Triebskorn, Rita [Steinbeis-Transfer Center for Ecotoxicology and Ecophysiology, Rottenburg (Germany); Jungmann, Dirk [Inst. of Hydrobiology, Dresden Univ. of Tech. (Germany); Giesy, John P. [Dept. of Veterinary Biomedical Sciences and Toxicology Centre, Univ. of Saskatchewan, Saskatoon (Canada); Zoology Dept., National Food Safety and Toxicology Center, and Center for Integrative Toxicology Center, and Center for Integrative Toxicology, Michigan State Univ., East Lansing, MI (United States); Biology and Chemistry Dept., City Univ. of Hong Kong, Kowloon, Hong Kong (China); School of the Environment, Nanjing Univ. (China)

    2010-04-15

    The aim of the present study was to investigate possible relationships between the sediment contaminants and the occurrence of intersex in situ. Two of the studied sediments were from polluted sites with increased occurrence of intersex crustaceans (Lake Pilnok, black coal mining area in the Czech Republic, inhabited by the crayfish Pontastacus leptodactylus population with 18% of intersex; creek Lockwitzbach in Germany with Gammarus fossarum population with about 7% of intersex). Materials and methods Sediments were studied by a combined approach that included (1) determination of concentrations of metals and traditionally analyzed organic pollutants such as polychlorinated biphenyls, pesticides, and polycyclic aromatic hydrocarbons (PAHs); (2) examination of the in vitro potencies to activate aryl hydrocarbon (AhR), estrogen (ER), and androgen receptor-mediated responses; and (3) in vivo whole sediment exposures during a 12-week reproduction toxicity study with benthic amphipod G. fossarum. (orig.)

  1. Homoclinic bifurcation in a Hodgkin-Huxley model of thermally sensitive neurons

    International Nuclear Information System (INIS)

    Feudel, Ulrike; Neiman, Alexander; Pei, Xing; Wojtenek, Winfried; Braun, Hans; Huber, Martin; Moss, Frank

    2000-01-01

    We study global bifurcations of the chaotic attractor in a modified Hodgkin-Huxley model of thermally sensitive neurons. The control parameter for this model is the temperature. The chaotic behavior is realized over a wide range of temperatures and is visualized using interspike intervals. We observe an abrupt increase of the interspike intervals in a certain temperature region. We identify this as a homoclinic bifurcation of a saddle-focus fixed point which is embedded in the chaotic attractors. The transition is accompanied by intermittency, which obeys a universal scaling law for the average length of trajectory segments exhibiting only short interspike intervals with the distance from the onset of intermittency. We also present experimental results of interspike interval measurements taken from the crayfish caudal photoreceptor, which qualitatively demonstrate the same bifurcation structure. (c) 2000 American Institute of Physics

  2. Homoclinic bifurcation in a Hodgkin-Huxley model of thermally sensitive neurons

    Energy Technology Data Exchange (ETDEWEB)

    Feudel, Ulrike [Department of Physics, University of Potsdam, Potsdam 14415, (Germany); Neiman, Alexander [Center for Neurodynamics, University of Missouri at St. Louis, St. Louis, Missouri 63121 (United States); Pei, Xing [Center for Neurodynamics, University of Missouri at St. Louis, St. Louis, Missouri 63121 (United States); Wojtenek, Winfried [Center for Neurodynamics, University of Missouri at St. Louis, St. Louis, Missouri 63121 (United States); Braun, Hans [Institute of Physiology, University of Marburg, Marburg 35037, (Germany); Huber, Martin [Institute of Physiology, University of Marburg, Marburg 35037, (Germany); Moss, Frank [Center for Neurodynamics, University of Missouri at St. Louis, St. Louis, Missouri 63121 (United States)

    2000-03-01

    We study global bifurcations of the chaotic attractor in a modified Hodgkin-Huxley model of thermally sensitive neurons. The control parameter for this model is the temperature. The chaotic behavior is realized over a wide range of temperatures and is visualized using interspike intervals. We observe an abrupt increase of the interspike intervals in a certain temperature region. We identify this as a homoclinic bifurcation of a saddle-focus fixed point which is embedded in the chaotic attractors. The transition is accompanied by intermittency, which obeys a universal scaling law for the average length of trajectory segments exhibiting only short interspike intervals with the distance from the onset of intermittency. We also present experimental results of interspike interval measurements taken from the crayfish caudal photoreceptor, which qualitatively demonstrate the same bifurcation structure. (c) 2000 American Institute of Physics.

  3. A new genus and species of entocytherid ostracod (Ostracoda: Entocytheridae) from the John Day River Basin of Oregon, U.S.A., with a key to genera of the subfamily Entocytherinae.

    Science.gov (United States)

    Weaver, Patricia G; Williams, Bronwyn W

    2017-06-07

    Targeted sampling efforts by the authors for the signal crayfish, Pacifastacus leniusculus, from its native range in the John Day River Basin, Oregon, U.S.A. yielded entocytherid ostracods with a male copulatory complex so clearly different from other entocytherines that a new genus, Aurumcythere gen. nov. is proposed to receive them. This newly proposed, apparently nonsclerotized, genus with hook and spur-like prominences of the posteroventral end of the peniferum is the first new genus of the subfamily Entocytherinae named since Hobbs & Peters described Aphelocythere (= Waltoncythere) in 1977. Aurumcythere gen. nov. represents only the second genus of entocytherid known from the Pacific Northwest. Lack of sclerotization in Aurumcythere gen. nov. provides new insight into poorly understood mating behaviors of entocytherid ostracods.

  4. Fossilized spermatozoa preserved in a 50-Myr-old annelid cocoon from Antarctica.

    Science.gov (United States)

    Bomfleur, Benjamin; Mörs, Thomas; Ferraguti, Marco; Reguero, Marcelo A; McLoughlin, Stephen

    2015-07-01

    The origin and evolution of clitellate annelids--earthworms, leeches and their relatives--is poorly understood, partly because body fossils of these delicate organisms are exceedingly rare. The distinctive egg cases (cocoons) of Clitellata, however, are relatively common in the fossil record, although their potential for phylogenetic studies has remained largely unexplored. Here, we report the remarkable discovery of fossilized spermatozoa preserved within the secreted wall layers of a 50-Myr-old clitellate cocoon from Antarctica, representing the oldest fossil animal sperm yet known. Sperm characters are highly informative for the classification of extant Annelida. The Antarctic fossil spermatozoa have several features that point to affinities with the peculiar, leech-like 'crayfish worms' (Branchiobdellida). We anticipate that systematic surveys of cocoon fossils coupled with advances in non-destructive analytical methods may open a new window into the evolution of minute, soft-bodied life forms that are otherwise only rarely observed in the fossil record.

  5. Artificial lateral line with biomimetic neuromasts to emulate fish sensing

    International Nuclear Information System (INIS)

    Yang Yingchen; Chen Nannan; Tucker, Craig; Hu Huan; Liu Chang; Nguyen, Nam; Lockwood, Michael; Jones, Douglas L; Bleckmann, Horst

    2010-01-01

    Hydrodynamic imaging using the lateral line plays a critical role in fish behavior. To engineer such a biologically inspired sensing system, we developed an artificial lateral line using MEMS (microelectromechanical system) technology and explored its localization capability. Arrays of biomimetic neuromasts constituted an artificial lateral line wrapped around a cylinder. A beamforming algorithm further enabled the artificial lateral line to image real-world hydrodynamic events in a 3D domain. We demonstrate that the artificial lateral line system can accurately localize an artificial dipole source and a natural tail-flicking crayfish under various conditions. The artificial lateral line provides a new sense to man-made underwater vehicles and marine robots so that they can sense like fish.

  6. Contribution to the improvement of a porridge made with fermented maize: effect of selected foods and lemon on energy density, pH, viscosity and nutritional quality.

    Science.gov (United States)

    Ejigui, Jeanne; Desrosiers, Therese

    2011-08-01

    The objective of the present study was to use lemon and selected foods to improve the nutritional characteristics, quality and the nutrient content of a traditional complementary porridge made of lactic acid fermented yellow maize. Boiled egg yolk, roasted peanut paste, dry crayfish flour, roasted soybean flour and lemon juice were used as food additions. Amounts of food added were calculated on the basis of World Health Organization estimated energy needs from complementary foods of well-nourished children in developing countries, aged 9-11 months, at four servings per day and a low amount of breast milk energy. The pH and viscosity increased in porridges with food addition, but lemon juice contributed to lowering them. Energy and nutrient densities/100 g porridge improved with food addition regardless of the use of lemon juice. An increase in iron, zinc and calcium in vitro availability was observed (P lemon juice.

  7. Oxygen uptake by excised gills of Procambarus clarkii (Girard) from Albufera Lake of Valencia, Spain, under heavy metal treatments

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Mayans, J.; Torreblanca, A.; Del Ramo, J.; Nunez, A.

    1986-06-01

    The American red crayfish Procambarus clarkii, originally from Louisiana (USA) was introduced in Spain in the 70's in the Guadalquivir River swamps. It appeared first randomly and in a more regular basis afterwards since 1978 in the Albufera Lake south of Valencia and in the surrounding rice fields. Albufera lake and surrounding rice fields waters are being subject since the last three decades to very heavy load of sewage, toxic industrial residues including heavy metals and pesticides from the many urban and industrial settlements in the zone. In the present study, the authors have investigated the effect that heavy metals (Chromium, Cadmium and Mercury) have on the oxygen uptake by excised bills of Procambarus clarkii (Girard) coming from the Albufera Lake (Valencia).

  8. Information to support to monitoring and habitat restoration on Ash Meadows National Wildlife Refuge

    Science.gov (United States)

    Scoppettone, G. Gary

    2013-01-01

    The Ash Meadows National Wildlife Refuge staff focuses on improving habitat for the highest incidence of endemic species for an area of its size in the continental United States. Attempts are being made to restore habitat to some semblance of its pre-anthropogenic undisturbed condition, and to provide habitat conditions to which native plant and animal species have evolved. Unfortunately, restoring the Ash Meadows’ Oases to its pre-anthropogenic undisturbed condition is almost impossible. First, there are constraints on water manipulation because there are private holdings within the refuge boundary; second, there has been at least one species extinction—the Ash Meadows pool fish (Empetrichthys merriami). It is also quite possible that thermal endemic invertebrate species were lost before ever being described. Perhaps the primary obstacle to restoring Ash Meadows to its pre-anthropogenic undisturbed conditions is the presence of invasive species. However, invasive species, such as red swamp crayfish (Procambarus clarki) and western mosquitofish (Gambusia affinis), are a primary driving force in restoring Ash Meadows’ spring systems, because under certain habitat conditions they can all but replace native species. Returning Ash Meadows’ physical landscape to some semblance of its pre-anthropogenic undisturbed condition through natural processes may take decades. Meanwhile, the natural dissolution of concrete and earthen irrigation channels threatens to allow cattail marshes to flourish instead of spring-brooks immediately downstream of spring discharge. This successional stage favors non-native crayfish and mosquitofish over the native Amargosa pupfish (Cyprinodon nevadensis). Thus, restoration is needed to control non-natives and to promote native species, and without such intervention the probability of native fish reduction or loss, is anticipated. The four studies in this report are intended to provide information for restoring native fish habitat and

  9. Predator diversity effects in an exotic freshwater food web.

    Science.gov (United States)

    Naddafi, Rahmat; Rudstam, Lars G

    2013-01-01

    Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs)] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs)]. How the relative importance of these two indirect interactions varies with predator diversity remains poorly understood. We tested the effect of predator diversity on both TMIIs and DMIIs on phytoplankton using two competitive invasive dreissenid mussel species (zebra mussel and quagga mussel) as the herbivores and combinations of one, two or all three species of the predators pumpkinseed sunfish, round goby, and rusty crayfish. Predators had either direct access to mussels and induced both TMII and DMII, or no direct access and induced only TMII through the presence of risk cues. In both sets of treatments, the predators induced a trophic cascade which resulted in more phytoplankton remaining with predators present than with only mussels present. The trophic cascade was weaker in three-predator and two-predator treatments than in one-predator treatments when predators had direct access to dreissenids (DMIIs and TMIIs). Crayfish had higher cascading effects on phytoplankton than both pumpkinseed and round goby. Increased predator diversity decreased the strength of DMIIs but had no effect on the strength of TMIIs. The strength of TMIIs was higher with zebra than quagga mussels. Our study suggests that inter-specific interference among predators in multi-species treatments weakens the consumptive cascading effects of predation on lower trophic levels whereas the importance of predator diversity on trait mediated effects depends on predator identity.

  10. Crustacean hyperglycemic hormone (cHH) as a modulator of aggression in crustacean decapods.

    Science.gov (United States)

    Aquiloni, Laura; Giulianini, Piero G; Mosco, Alessandro; Guarnaccia, Corrado; Ferrero, Enrico; Gherardi, Francesca

    2012-01-01

    Biogenic amines, particularly serotonin, are recognised to play an important role in controlling the aggression of invertebrates, whereas the effect of neurohormones is still underexplored. The crustacean Hyperglycemic Hormone (cHH) is a multifunctional member of the eyestalk neuropeptide family. We expect that this neuropeptide influences aggression either directly, by controlling its expression, or indirectly, by mobilizing the energetic stores needed for the increased activity of an animal. Our study aims at testing such an influence and the possible reversion of hierarchies in the red swamp crayfish, Procambarus clarkii, as a model organism. Three types of pairs of similarly sized males were formed: (1) 'control pairs' (CP, n = 8): both individuals were injected with a phosphate saline solution (PBS); (2) 'reinforced pairs' (RP, n = 9): the alpha alone was injected with native cHH, and the beta with PBS; (3) 'inverted pairs' (IP, n = 9): the opposite of (2). We found that, independently of the crayfish's prior social experience, cHH injections induced (i) the expression of dominance behaviour, (ii) higher glycemic levels, and (iii) lower time spent motionless. In CP and RP, fight intensity decreased with the establishment of dominance. On the contrary, in IP, betas became increasingly likely to initiate and escalate fights and, consequently, increased their dominance till a temporary reversal of the hierarchy. Our results demonstrate, for the first time, that, similarly to serotonin, cHH enhances individual aggression, up to reverse, although transitorily, the hierarchical rank. New research perspectives are thus opened in our intriguing effort of understanding the role of cHH in the modulation of agonistic behaviour in crustaceans.

  11. Crustacean hyperglycemic hormone (cHH as a modulator of aggression in crustacean decapods.

    Directory of Open Access Journals (Sweden)

    Laura Aquiloni

    Full Text Available Biogenic amines, particularly serotonin, are recognised to play an important role in controlling the aggression of invertebrates, whereas the effect of neurohormones is still underexplored. The crustacean Hyperglycemic Hormone (cHH is a multifunctional member of the eyestalk neuropeptide family. We expect that this neuropeptide influences aggression either directly, by controlling its expression, or indirectly, by mobilizing the energetic stores needed for the increased activity of an animal. Our study aims at testing such an influence and the possible reversion of hierarchies in the red swamp crayfish, Procambarus clarkii, as a model organism. Three types of pairs of similarly sized males were formed: (1 'control pairs' (CP, n = 8: both individuals were injected with a phosphate saline solution (PBS; (2 'reinforced pairs' (RP, n = 9: the alpha alone was injected with native cHH, and the beta with PBS; (3 'inverted pairs' (IP, n = 9: the opposite of (2. We found that, independently of the crayfish's prior social experience, cHH injections induced (i the expression of dominance behaviour, (ii higher glycemic levels, and (iii lower time spent motionless. In CP and RP, fight intensity decreased with the establishment of dominance. On the contrary, in IP, betas became increasingly likely to initiate and escalate fights and, consequently, increased their dominance till a temporary reversal of the hierarchy. Our results demonstrate, for the first time, that, similarly to serotonin, cHH enhances individual aggression, up to reverse, although transitorily, the hierarchical rank. New research perspectives are thus opened in our intriguing effort of understanding the role of cHH in the modulation of agonistic behaviour in crustaceans.

  12. Involvement of the PI3K/Akt/GSK3β pathway in photodynamic injury of neurons and glial cells

    Science.gov (United States)

    Komandirov, M. A.; Knyazeva, E. A.; Fedorenko, Y. P.; Rudkovskii, M. V.; Stetsurin, D. A.; Uzdensky, A. B.

    2011-03-01

    Photodynamic treatment causes intense oxidative stress and kills cells. It is currently used in neurooncology. However, along with tumor it damages surrounding healthy neuronal and glial cells. In order to study the possible role of the phosphatidylinositol 3-kinase/protein kinase Akt/glycogen synthase kinase-3β signaling pathway in photodynamic damage to normal neurons and glia, we used isolated crayfish stretch receptor that consists only of a single neuron surrounded by glial cells. It was photosensitized with alumophthalocyanine Photosens (100 nM). The laser diode (670nm, 0.4W/cm2) was used as a light source. Application of specific inhibitors of the enzymes involved in this pathway showed that phosphatidylinositol 3-kinase did not participate in photoinduced death of neurons and glia. Protein kinase Akt was involved in photoinduced necrosis but not in apoptosis of neurons and glia. Glycogen synthase kinase-3β participated in photoinduced apoptosis of glial cells and in necrosis of neurons. Therefore, the phosphatidylinositol 3-kinase/protein kinase Akt/glycogen synthase kinase-3β pathway was not involved as a whole in photodynamic injury of crayfish neurons and glial cells but its components, protein kinase Akt and glycogen synthase kinase-3β, independently and cell-specifically regulated photoinduced death of neurons and glial cells. These data showed that in this system necrosis was not non-regulated and catastrophic mode of cell death. It was controlled by some signaling proteins. The obtained results may be used for search of pharmacological agents that selectively modulate injury of normal neurons and glial cells during photodynamic therapy of brain tumors.

  13. Faunal assemblages and multi-scale habitat patterns in headwater tributaries of the South Fork Trinity River - an unregulated river embedded within a multiple-use landscape

    Science.gov (United States)

    Welsh, H.H.; Hodgson, G.R.; Duda, J.J.; Emlen, J.M.

    2010-01-01

    Headwaters can represent 80% of stream kilometers in a watershed, and they also have unique physical and biological properties that have only recently been recognized for their importance in sustaining healthy functioning stream networks and their ecological services. We sampled 60 headwater tributaries in the South Fork Trinity River, a 2,430 km2, mostly forested, multiple-use watershed in northwestern California. Our objectives were: (1) to differentiate unique headwater types using 69 abiotic and vegetation variables measured at three spatial scales, and then to reduce these to informative subsets; (2) determine if distinct biota occupied the different tributary types; (3) determine the environmental attributes associated with the presence and abundance of these biotic assemblages; and (4) using niche modeling, determine key attribute thresholds to illustrate how these biota could be employed as metrics of system integrity and ecological services. Several taxa were sufficiently abundant and widespread to use as bio-indicators: the presence and abundance of steelhead trout (Oncorhynchus mykiss), herpetofauna (reptile and amphibian) species richness, and signal crayfish (Pacifastacus leniusculus) represented different trophic positions, value as commercial resources (steelhead), sensitivity to environmental stress (amphibians), and indicators of biodiversity (herpetofauna species richness). Herpetofauna species richness did not differ, but abundances of steelhead trout, signal crayfish, and amphibian richness all differed significantly among tributary types. Niche models indicated that distribution and abundance patterns in both riparian and aquatic environments were associated with physical and structural attributes at multiple spatial scales, both within and around reaches. The bio-indicators responded to unique sets of attributes, reflecting the high environmental heterogeneity in headwater tributaries across this large watershed. These niche attributes

  14. Faunal assemblages and multi-scale habitat patterns in headwater tributaries of the South Fork Trinity River – an unregulated river embedded within a multiple-use landscape

    Directory of Open Access Journals (Sweden)

    Welsh, H. H., Jr.,

    2010-06-01

    Full Text Available Headwaters can represent 80% of stream kilometers in a watershed, and they also have unique physical and biological properties that have only recently been recognized for their importance in sustaining healthy functioning stream networks and their ecological services. We sampled 60 headwater tributaries in the South Fork Trinity River, a 2,430 km2, mostly forested, multiple-use watershed in northwestern California. Our objectives were: (1 to differentiate unique headwater types using 69 abiotic and vegetation variables measured at three spatial scales, and then to reduce these to informative subsets; (2 determine if distinct biota occupied the different tributary types; (3 determine the environmental attributes associated with the presence and abundance of these biotic assemblages; and (4 using niche modeling, determine key attribute thresholds to illustrate how these biota could be employed as metrics of system integrity and ecological services. Several taxa were sufficiently abundant and widespread to use as bio-indicators: the presence and abundance of steelhead trout (Oncorhynchus mykiss, herpetofauna (reptile and amphibian species richness, and signal crayfish (Pacifastacus leniusculus represented different trophic positions, value as commercial resources (steelhead, sensitivity to environmental stress (amphibians, and indicators of biodiversity (herpetofauna species richness. Herpetofauna species richness did not differ, but abundances of steelhead trout, signal crayfish, and amphibian richness all differed significantly among tributary types. Niche models indicated that distribution and abundance patterns in both riparian and aquatic environments were associated with physical and structural attributes at multiple spatial scales, both within and around reaches. The bio-indicators responded to unique sets of attributes, reflecting the high environmental heterogeneity in headwater tributaries across this large watershed. These niche

  15. Relative abundance and distribution of fishes within an established Area of Critical Environmental Concern, of the Amargosa River Canyon and Willow Creek, Inyo and San Bernardino Counties, California

    Science.gov (United States)

    Scoppettone, G. Gary; Hereford, Mark E.; Rissler, Peter H.; Johnson, Danielle M.; Salgado, Antonio

    2011-01-01

    The Amargosa River Canyon of San Bernardino and Inyo County, California, has been designated by the Bureau of Land Management as an Area of Critical Environmental Concern, due in part to its unique flora and fauna. As a task of the Area of Critical Environmental Concern implementation plan, a survey of native fishes was conducted from June 21 to August 12, 2010. Geographic Information System tools were used to map sampling locations, which were spaced at 50-meter intervals. Global Positioning Systems were used to locate sampling stations, and stations with adequate water for successful trapping were sampled with baited minnow traps. Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were widespread throughout Armargosa River Canyon. Throughout the study area 8,558 pupfish were captured at 194 stations; 3,472 speckled dace were captured at 210 stations; 238 red-swamp crayfish (Procambarus clarkia) were captured at 83 stations; and 1,095 western mosquitofish (Gambusia affinus) were captured at 110 stations. Pupfish were most abundant in open water habitat with native riparian vegetation, and they were significantly less abundant where the stream was completely covered by cattails or where saltcedar (Tamarix sp.) dominated the riparian corridor. There was no relationship between stream cover and speckled dace distribution. Non-native western mosquitofish and red-swamp crayfish densities were significantly higher in stream reaches dominated by saltcedar. The continued spread of saltcedar threatens to negatively affect pupfish and potentially reduce speckled dace abundance throughout the Amargosa River Canyon. This study can serve as baseline information for observing native fish populations in the future, as related to potential changes to the Amargosa River Canyon ecosystem.

  16. Increasing potential risk of a global aquatic invader in Europe in contrast to other continents under future climate change.

    Science.gov (United States)

    Liu, Xuan; Guo, Zhongwei; Ke, Zunwei; Wang, Supen; Li, Yiming

    2011-03-30

    Anthropogenically-induced climate change can alter the current climatic habitat of non-native species and can have complex effects on potentially invasive species. Predictions of the potential distributions of invasive species under climate change will provide critical information for future conservation and management strategies. Aquatic ecosystems are particularly vulnerable to invasive species and climate change, but the effect of climate change on invasive species distributions has been rather neglected, especially for notorious global invaders. We used ecological niche models (ENMs) to assess the risks and opportunities that climate change presents for the red swamp crayfish (Procambarus clarkii), which is a worldwide aquatic invasive species. Linking the factors of climate, topography, habitat and human influence, we developed predictive models incorporating both native and non-native distribution data of the crayfish to identify present areas of potential distribution and project the effects of future climate change based on a consensus-forecast approach combining the CCCMA and HADCM3 climate models under two emission scenarios (A2a and B2a) by 2050. The minimum temperature from the coldest month, the human footprint and precipitation of the driest quarter contributed most to the species distribution models. Under both the A2a and B2a scenarios, P. clarkii shifted to higher latitudes in continents of both the northern and southern hemispheres. However, the effect of climate change varied considerately among continents with an expanding potential in Europe and contracting changes in others. Our findings are the first to predict the impact of climate change on the future distribution of a globally invasive aquatic species. We confirmed the complexities of the likely effects of climate change on the potential distribution of globally invasive species, and it is extremely important to develop wide-ranging and effective control measures according to predicted

  17. The Emergence and Epidemiology of Haff Disease in China

    Directory of Open Access Journals (Sweden)

    Thomas Y. K. Chan

    2016-12-01

    Full Text Available Haff disease is a rare syndrome of unexplained myalgia and rhabdomyolysis occurring within 24 h of consumption of certain types of cooked freshwater fish or crustacean. It is caused by a yet unidentified heat-stable toxin. In the present review of published case studies and official press releases, the main objective is to report the emergence and epidemiology of Haff disease in China. Haff disease first occurred in Beijing in 2000 and in Lianzhou and Liannan, Guangdong Province in 2009. Subsequent outbreaks mostly occurred in the Jiangsu Province—Nanjing, Yangzhou, Huai’an, and Yancheng. Isolated outbreaks occurred in other cities since 2010—Shijiazhuang, Yueyang, Shanghai, Wuhu, Baoding, Shenzhen, and Hong Kong (imported cases from Shenzhen. Outbreaks occurred predominately in the summer. Crayfish accounted for almost all the outbreaks. Two large outbreaks occurred in Lianzhou and Liannan in 2009 (n = 54 after eating pomfrets and in Nanjing in 2010 (n = 42 after eating crayfish. Other reports or outbreaks involved only 1–9 subjects (median 2 subjects. Variability in individual susceptibility and attack rates were noted, with many subjects remaining asymptomatic despite sharing the same seafood meal as the index cases. Adults were predominately involved. Symptoms occurred within 3–20 h of seafood ingestion, including myalgia, weakness, and, less frequently, nausea, vomiting, abdominal pain, and diarrhea. Myalgia and muscle weakness should normally subside within 2–3 days. Serum creatine phosphokinase became normal within 5–6 days. Abnormal renal function was uncommon. Serious complications (renal failure, multi-organ failure, and prolonged myopathy and death were rare. In any subjects with unexplained myalgia and rhabdomyolysis, seafood consumption should be included in the history. All suspected cases of Haff disease, including milder presentations, should be reported to public health authorities.

  18. Plastic responses of a sessile prey to multiple predators: a field and experimental study.

    Directory of Open Access Journals (Sweden)

    Philipp Emanuel Hirsch

    Full Text Available Theory predicts that prey facing a combination of predators with different feeding modes have two options: to express a response against the feeding mode of the most dangerous predator, or to express an intermediate response. Intermediate phenotypes protect equally well against several feeding modes, rather than providing specific protection against a single predator. Anti-predator traits that protect against a common feeding mode displayed by all predators should be expressed regardless of predator combination, as there is no need for trade-offs.We studied phenotypic anti-predator responses of zebra mussels to predation threat from a handling-time-limited (crayfish and a gape-size-limited (roach predator. Both predators dislodge mussels from the substrate but diverge in their further feeding modes. Mussels increased expression of a non-specific defense trait (attachment strength against all combinations of predators relative to a control. In response to roach alone, mussels showed a tendency to develop a weaker and more elongated shell. In response to crayfish, mussels developed a harder and rounder shell. When exposed to either a combination of predators or no predator, mussels developed an intermediate phenotype. Mussel growth rate was positively correlated with an elongated weaker shell and negatively correlated with a round strong shell, indicating a trade-off between anti-predator responses. Field observations of prey phenotypes revealed the presence of both anti-predator phenotypes and the trade-off with growth, but intra-specific population density and bottom substrate had a greater influence than predator density.Our results show that two different predators can exert both functionally equivalent and inverse selection pressures on a single prey. Our field study suggests that abiotic factors and prey population density should be considered when attempting to explain phenotypic diversity in the wild.

  19. Predator diversity effects in an exotic freshwater food web.

    Directory of Open Access Journals (Sweden)

    Rahmat Naddafi

    Full Text Available Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs]. How the relative importance of these two indirect interactions varies with predator diversity remains poorly understood. We tested the effect of predator diversity on both TMIIs and DMIIs on phytoplankton using two competitive invasive dreissenid mussel species (zebra mussel and quagga mussel as the herbivores and combinations of one, two or all three species of the predators pumpkinseed sunfish, round goby, and rusty crayfish. Predators had either direct access to mussels and induced both TMII and DMII, or no direct access and induced only TMII through the presence of risk cues. In both sets of treatments, the predators induced a trophic cascade which resulted in more phytoplankton remaining with predators present than with only mussels present. The trophic cascade was weaker in three-predator and two-predator treatments than in one-predator treatments when predators had direct access to dreissenids (DMIIs and TMIIs. Crayfish had higher cascading effects on phytoplankton than both pumpkinseed and round goby. Increased predator diversity decreased the strength of DMIIs but had no effect on the strength of TMIIs. The strength of TMIIs was higher with zebra than quagga mussels. Our study suggests that inter-specific interference among predators in multi-species treatments weakens the consumptive cascading effects of predation on lower trophic levels whereas the importance of predator diversity on trait mediated effects depends on predator identity.

  20. Seasonal variation of the effect of high-carbohydrate and high-protein diets on the intermediate metabolism of Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae maintained in the laboratory Variações sazonais do efeito de uma dieta rica em carboidrato e rica em proteínas no metabolismo intermediário de Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae mantidos em laboratório

    Directory of Open Access Journals (Sweden)

    Bibiana K. Dutra

    2008-12-01

    Full Text Available The goal of this study was to evaluate the effect of a high-carbohydrate diet (HC and a high-protein diet (HP on the metabolism of the crayfish Parastacus brasiliensis (Von Martens, 1869, collected in different seasons and maintained in the laboratory for 15 days. Crayfish were collected monthly from January 2002 to January 2004 at São Francisco de Paula, Southern Brazil, in Guarapirá stream. In the laboratory, the animals were kept submerged in aquariums under controlled conditions. They were fed ad libitum, for 15 days with either a HC or HP diet. At the end of this period, haemolymph samples were collected, as were hepatopancreas, gills, and abdominal muscle that were removed for determination of glycogen, free glucose, lipids, and triglycerides. The haemolymph samples were used for determination of glucose, proteins, lipids, and triglycerides. Statistical analysis (ANOVA revealed significant seasonal differences in biochemical composition in crayfish maintained on HC or HP diets. Independent of the diets offered to the animals and the controlled conditions for 15 days, the indications of seasonality were unchanged. The observed changes seemed to be related to the reproductive period. Moreover, the HC diet increased all energy reserves in adult parastacids, which may aid in reproduction.O objetivo deste estudo foi avaliar o efeito da dieta rica em carboidratos (HC e da dieta rica em proteínas (HP sobre o metabolismo do Parastacus brasiliensis (Von Martens, 1869 coletados em diferentes estações e mantidos durante 15 dias em laboratório. Os lagostins foram coletados mensalmente de Janeiro de 2002 a Janeiro de 2004 em São Francisco de Paula, Sul do Brasil, no riacho Guarapirá. No laboratório, os animais foram mantidos submersos em aquários sob condições controladas. Eles foram alimentados ad libitum por 15 dias com a dieta HC ou HP. Após o final do período, as amostras de hemolinfa foram coletadas, assim como o hepatopâncreas, as

  1. Banks Lake Fishery Evaluation Project Annual Report : Fiscal Year 2008 (March 1, 2008 to February 1, 2009).

    Energy Technology Data Exchange (ETDEWEB)

    Polacek, Matt [Washington Department of Fish and Wildlife

    2009-07-15

    The Washington Department of Fish and Wildlife implemented the Banks Lake Fishery Evaluation Project (BLFEP) in September 2001 with funds from the Bonneville Power Administration, and continued project tasks in 2008. The objective was to evaluate factors that could limit kokanee in Banks Lake, including water quality, prey availability, harvest, and acute predation during hatchery releases. Water quality parameters were collected twice monthly from March through November. Banks Lake water temperatures began to increase in May and stratification was apparent by July. By late August, the thermocline had dropped to 15 meters deep, with temperatures of 21-23 C in the epilimnion and 16-19 C in the hypolimnion. Dissolved oxygen levels were generally above 8 mg/L until August when they dropped near or below 5 mg/L deeper than 20-meters. Secchi depths ranged from 3.2 to 6.2 meters and varied spatially and temporally. Daphnia and copepod densities were the highest in May and June, reaching densities of 26 copepods/liter and 9 Daphnia/liter. Fish surveys were conducted in July and October 2008 using boat electrofishing, gill netting, and hydroacoustic surveys. Lake whitefish (71%) and yellow perch (16%) dominated the limnetic fish assemblage in the summer, while lake whitefish (46%) and walleye (22%) were the most abundant in gill net catch during the fall survey. Piscivore diets switched from crayfish prior to the release of rainbow trout to crayfish and rainbow trout following the release. The highest angling pressure occurred in May, when anglers were primarily targeting walleye and smallmouth bass. Boat anglers utilized Steamboat State Park more frequently than any other boat ramp on Banks Lake. Shore anglers used the rock jetty at Coulee City Park 45% of the time, with highest use occurring from November through April. Ice fishing occurred in January and February at the south end of the lake. An estimated total of 4,397 smallmouth bass, 11,106 walleye, 371 rainbow trout

  2. Cross-talk among immune and neuroendocrine systems in molluscs and other invertebrate models.

    Science.gov (United States)

    Malagoli, Davide; Ottaviani, Enzo

    2017-02-01

    The comparison between immune and neuroendocrine systems in vertebrates and invertebrates suggest an ancient origin and a high degree of conservation for the mechanisms underlying the integration between immune and stress responses. This suggests that in both vertebrates and invertebrates the stress response involves the integrated network of soluble mediators (e.g., neurotransmitters, hormones and cytokines) and cell functions (e.g., chemotaxis and phagocytosis), that interact with a common objective, i.e., the maintenance of body homeostasis. During evolution, several changes observed in the stress response of more complex taxa could be the result of new roles of ancestral molecules, such as ancient immune mediators may have been recruited as neurotransmitters and hormones, or vice versa. We review older and recent evidence suggesting that immune and neuro-endocrine functions during the stress response were deeply intertwined already at the dawn of multicellular organisms. These observations found relevant reflections in the demonstration that immune cells can transdifferentiate in olfactory neurons in crayfish and the recently re-proposed neural transdifferentiation in humans. Copyright © 2016. Published by Elsevier Inc.

  3. Ecotoxicological impact of Zequanox®, a novel biocide, on selected non-target Irish aquatic species.

    Science.gov (United States)

    Meehan, Sara; Shannon, Adam; Gruber, Bridget; Rackl, Sarahann M; Lucy, Frances E

    2014-09-01

    Effective, species-specific zebra mussel control is needed urgently for Ireland׳s freshwater bodies, which became infested with non-native zebra mussels in the 1990s. Zequanox®, a newly commercialized product for zebra and quagga mussel control, is composed of dead Pseudomonas fluorescens CL 145A cells. This paper describes ecotoxicology tests on three representative native Irish freshwater species: Anodonta (duck mussel), Chironomus plumosus (non-biting midge), and Austropotamobius pallipes (white-clawed crayfish). The species were exposed to Zequanox in a 72-h static renewal toxicity test at concentrations of 100-750mg active ingredient per liter (mga.i./L). Water quality parameters were measured every 12-24h before and after water and product renewal. After 72h, endpoints were reported as LC10, LC50, and LC100. The LC50 values derived were (1) Anodonta: ≥500mga.i./L (2) C. plumosus: 1075mga.i./L, and (3) A. pallipes: ≥750mga.i./L. These results demonstrate that Zequanox does not negatively affect these organisms at the concentration required for >80percent zebra mussel mortality (150mg a.i/L) and the maximum allowable treatment concentration in the United Sates (200mga.i./L). They also show the overall species-specificity of Zequanox, and support its use in commercial facilities and open waters. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Behavioral responses of anuran larvae to chemical cues of native and introduced predators in the Pacific Northwestern United States

    Science.gov (United States)

    Pearl, Christopher A.; Adams, Michael J.; Schuytema, Gerald S.; Nebeker, A.V.

    2003-01-01

    We compared behavioral responses of larvae of three Pacific Northwest anurans from different hydroperiods to water borne cues of native and introduced predators. Two native anurans (Pacific Treefrog, Pseudacris regilla, and Northern Red-Legged Frog, Rana aurora aurora) and introduced Bullfrogs (Rana catesbeiana) responded to water conditioned by native Redside Shiners (Richardsonius balteatus) by increasing refuge use. The larvae of the two native anurans differed in their response to introduced predator cues. Rana aurora aurora, which occur in temporary and permanent waters, responded to both introduced Bluegill Sunfish (Lepomis macrochirus) and introduced Crayfish (Procambarus clarkii). Pseudacris regilla, which occur primarily in temporary ponds, did not respond to water borne cues from either introduced predator. The broader responses of R. a. aurora may indicate greater behavioral plasticity or more exposure to novel predators than experienced by P. regilla. Larvae of introduced R. catesbeiana responded strongly to cues from two fish native to the Pacific northwest but did not alter behavior in response to any of five potential predators with which they coexist in their native range. Fish that occur with R. catesbeiana in their native range generally find Bullfrog larvae unpalatable. This pattern suggests that Bullfrog larvae can recognize cues of novel predators that may find them palatable, which could contribute to their success as an invasive species in the region.

  5. Demonstration of expression of a neuropeptide-encoding gene in crustacean hemocytes.

    Science.gov (United States)

    Wu, Su-Hua; Chen, Yan-Jhou; Huang, Shao-Yen; Tsai, Wei-Shiun; Wu, Hsin-Ju; Hsu, Tsan-Ting; Lee, Chi-Ying

    2012-04-01

    Crustacean hyperglycemic hormone (CHH) was originally identified in a neuroendocrine system-the X-organ/sinus gland complex. In this study, a cDNA (Prc-CHH) encoding CHH precursor was cloned from the hemocyte of the crayfish Procambarus clarkii. Analysis of tissues by a CHH-specific enzyme-linked immunosorbent assay (ELISA) confirmed the presence of CHH in hemocytes, the levels of which were much lower than those in the sinus gland, but 2 to 10 times higher than those in the thoracic and cerebral ganglia. Total hemocytes were separated by density gradient centrifugation into layers of hyaline cell (HC), semi-granular cell (SGC), and granular cell (GC). Analysis of extracts of each layer using ELISA revealed that CHH is present in GCs (202.8±86.7 fmol/mg protein) and SGCs (497.8±49.4 fmol/mg protein), but not in HCs. Finally, CHH stimulated the membrane-bound guanylyl cyclase (GC) activity of hemocytes in a dose-dependent manner. These data for the first time confirm that a crustacean neuropeptide-encoding gene is expressed in cells essential for immunity and its expression in hemocytes is cell type-specific. Effect of CHH on the membrane-bound GC activity of hemocyte suggests that hemocyte is a target site of CHH. Possible functions of the hemocyte-derived CHH are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. US cities can manage national hydrology and biodiversity using local infrastructure policy

    Science.gov (United States)

    Surendran Nair, Sujithkumar; DeRolph, Christopher R.; Ruddell, Benjamin L.; Morton, April M.; Stewart, Robert N.; Troia, Matthew J.; Tran, Liem; Kim, Hyun; Bhaduri, Budhendra L.

    2017-01-01

    Cities are concentrations of sociopolitical power and prime architects of land transformation, while also serving as consumption hubs of “hard” water and energy infrastructures. These infrastructures extend well outside metropolitan boundaries and impact distal river ecosystems. We used a comprehensive model to quantify the roles of anthropogenic stressors on hydrologic alteration and biodiversity in US streams and isolate the impacts stemming from hard infrastructure developments in cities. Across the contiguous United States, cities’ hard infrastructures have significantly altered at least 7% of streams, which influence habitats for over 60% of North America’s fish, mussel, and crayfish species. Additionally, city infrastructures have contributed to local extinctions in 260 species and currently influence 970 indigenous species, 27% of which are in jeopardy. We find that ecosystem impacts do not scale with city size but are instead proportionate to infrastructure decisions. For example, Atlanta’s impacts by hard infrastructures extend across four major river basins, 12,500 stream km, and contribute to 100 local extinctions of aquatic species. In contrast, Las Vegas, a similar size city, impacts cities have local policy choices that can reduce future impacts to regional aquatic ecosystems as they grow. By coordinating policy and communication between hard infrastructure sectors, local city governments and utilities can directly improve environmental quality in a significant fraction of the nation’s streams reaching far beyond their city boundaries. PMID:28827332

  7. The role of Ca 2+-related signaling in photodynamic injury of nerve and glial cells

    Science.gov (United States)

    Lobanov, A. V.; Petin, Y. O.; Uzdensky, A. B.

    2007-05-01

    Photodynamic therapy (PDT) inhibited and irreversibly abolished firing, caused necrosis of neurons, necrosis, apoptosis and proliferation of glial cells in the isolated crayfish stretch receptor. The role in these processes of the central components of Ca 2+-mediated signaling pathway: phospholipase C, calmodulin, calmodulin-dependent kinase II, and protein kinase C was studied using their inhibitors: ET-18, fluphenazine, KN-93, or staurosporine, respectively. ET-18 reduced functional inactivation of neurons, necrosis and apoptosis of glial cells. Fluphenazine and KN-93 reduced PDT-induced necrosis of neurons and glial cells. Staurosporine enhanced PDT-induced glial apoptosis. PDTinduced gliosis was prevented by KN-93 and staurosporine. Therefore, phospholipase C participated in neuron inactivation and glial necrosis and apoptosis. Calmodulin and calmodulin-dependent kinase II were involved in PDT-induced necrosis of neurons and glial cells but not in glial apoptosis. Protein kinase C protected glia from apoptosis and participated in PDT-induced gliosis and loss of neuronal activity. These data may be used for modulation of PDT of brain tumors.

  8. On the role of adenylate cyclase, tyrosine kinase, and tyrosine phosphatase in the response of nerve and glial cells to photodynamic impact

    Science.gov (United States)

    Kolosov, Mikhail S.; Bragin, D. E.; Dergacheva, Olga Y.; Vanzha, O.; Oparina, L.; Uzdensky, Anatoly B.

    2004-08-01

    The role of different intercellular signaling pathways involving adenylate cyclase (AC), receptor tyrosine kinase (RTK), tyrosine and serine/threonine protein phosphatases (PTP or PP, respectively) in the response of crayfish mechanoreceptor neuron (MRN) and surrounding glial cells to photodynamic effect of aluminum phthalocyanine Photosens have been studied. AC inhibition by MDL-12330A decreased neuron lifetime, whereas AC activation by forskolin increase it. Thus, increase in cAMP produced by activated AC protects SRN against photodynamic inactivation. Similarly, RTK inhibition by genistein decreased neuron lifetime, while inhibition of PTP or PP that remove phosphate groups from proteins, prolonged neuronal activity. AC inhibition reduced photoinduced damage of the plasma membrane, and, therefore, necrosis in neuronal and glial cells. RTK inhibition protected only neurons against PDT-induced membrane permeabilization while glial cells became lesser permeable under ortovanadate-mediated PTP inhibition. AC activation also prevented PDT-induced apoptosis in glial cells. PP inhibition enhanced apoptotic processes in photosensitized glial cells. Therefore, both intercellular signaling pathways involving AC and TRK are involved in the maintenance of neuronal activity, integrity of the neuronal and glial plasma membranes and in apoptotic processes in glia under photosensitization.

  9. Inactivation of Paragonimus westermani metacercariae in soy sauce-marinated and frozen freshwater crabs.

    Science.gov (United States)

    Kim, Tae Im; Oh, Se-Ra; Dai, Fuhong; Yang, Hyun-Jong; Ha, Sang-Do; Hong, Sung-Jong

    2017-03-01

    Soy sauce-marinated freshwater crabs (Eriocheir japonicus) are a source of human paragonimiasis. The viability of Paragonimus westermani metacercariae (PwMc) in marinated crabs was investigated in an experimental setting. The PwMc collected from freshwater crayfish were inoculated into freshwater crabs, which were then frozen or marinated in soy sauce. All PwMc in the freshwater crabs were inactivated after freezing for 48 h at -20 °C and after freezing for 12 h at -40 °C. After marinating for 32 days, the survival rate of PwMc in 5% NaCl soy sauce was 50%, in 7.5% NaCl soy sauce it was 33.3%, and in 10.0% NaCl soy sauce it was 31.3%. When marinated for 64 days, all PwMc were inactivated in all experimental groups. These results revealed that freezing and soy sauce marination were detrimental to the survival of PwMc in freshwater crabs. Specifically, freezing crabs for more than 48 h or soaking them in soy sauce containing at least 5.0% NaCl for 64 days can inactivate PwMc. These results can inform the production of the traditional Korean soy sauce-marinated freshwater crabs known as gejang.

  10. Venison, another source of Paragonimus westermani infection.

    Science.gov (United States)

    Yoshida, Ayako; Matsuo, Kayoko; Moribe, Junji; Tanaka, Ryusei; Kikuchi, Taisei; Nagayasu, Eiji; Misawa, Naoaki; Maruyama, Haruhiko

    2016-12-01

    Paragonimiasis is a typical food-borne parasitic disease, endemic in most parts of Asia, with sporadic case reports from American and African countries. The major source of infection is undercooked freshwater crab or crayfish, though consumption of wild boar meat is also responsible for the infection in Japan, because wild boar is a paratenic host for Paragonimus westermani. Recently, living juveniles of P. westermani were isolated from muscle of a sika deer, Cervus nippon, in Japan, raising the possibility that venison has been another source of infection. In order to clarify the potential contribution of venison consumption to the occurrence of paragonimiasis, we analysed dietary histories of those paragonimiasis patients in whose diagnoses we were involved between 2001 and 2015. Among 380 patients, freshwater crab had been consumed by 208 patients, wild boar meat by 190, and wild deer meat by 76 patients before the onset of the disease. Overall contribution of wild deer meat was estimated to be 6.8% to 20.0%, although in Oita and Gifu Prefectures, where a substantial proportion of patients had consumed raw venison, the contribution of venison consumption was much higher (27.5 to 62.1% and 42.1 to 78.9% in Oita and Gifu Prefectures, respectively). We demonstrated P. westermani-specific antibodies in the sera of 4 out of 160 sika deer from Gifu Prefecture, strongly suggesting that these deer were infected with P. westermani. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Paragonimus kellicotti: A Lung Infection in Our Own Backyard.

    Science.gov (United States)

    Johannesen, Eric; Nguyen, Van

    2016-01-01

    Paragonimiasis is an infection caused by the lung fluke of the genus Paragonimus. Within the United States, paragonimiasis has been commonly diagnosed in Southeast Asian immigrants infected with the Asian lung fluke Paragonimus westermani. Infections from the North American lung fluke, Paragonimus kellicotti, have been rare, although more infections have been seen in people in the Midwestern United States. A 29-year-old male with a history of pleomorphic xanthoastrocytoma presented with hemoptysis. A CT scan showed a mass in the left upper lung lobe. A biopsy showed eosinophils and parasite eggs, some with a recognizable operculum. Further investigation revealed that he takes canoe trips on rivers within Missouri and would eat crayfish caught from these rivers. A blood sample was confirmed positive for Paragonimiasis serologically at the Center for Disease Control. Paragonimus kellicotti is found in rivers within the Mississippi basin. Infection occurs by consuming uncooked or undercooked crawfish. Microscopic identification of parasite eggs has been the gold standard. Serologic tests have been developed to aid in the diagnosis. Patients typically present with fever and hemoptysis. Common CT findings include pleural effusion, a mass, and lymphadenopathy. Awareness of P. kellicotti is important to guide appropriate diagnostic testing and ensuring proper treatment.

  12. Paragonimiasis Acquired in the United States: Native and Nonnative Species

    Science.gov (United States)

    2013-01-01

    SUMMARY Paragonimiasis is a parasitic lung infection caused by lung flukes of the genus Paragonimus, with most cases reported from Asia and caused by P. westermani following consumption of raw or undercooked crustaceans. With the exception of imported P. westermani cases in immigrants, in travelers returning from areas of disease endemicity, and in clusters of acquired cases following consumption of imported Asian crabs, human paragonimiasis caused by native lung flukes is rarely described in the United States, which has only one indigenous species of lung fluke, Paragonimus kellicotti. Clinicians should inquire about the consumption of raw or undercooked freshwater crabs by immigrants, expatriates, and returning travelers, and the consumption of raw or undercooked crayfish in U.S. freshwater river systems where P. kellicotti is endemic when evaluating patients presenting with unexplained fever, cough, rales, hemoptysis, pleural effusions, and peripheral eosinophilia. Diagnostic evaluation by specific parasitological, radiological, serological, and molecular methods will be required in order to differentiate paragonimiasis from tuberculosis, which is not uncommon in recent Asian immigrants. All cases of imported and locally acquired paragonimiasis will require treatment with oral praziquantel to avoid any potential pulmonary and cerebral complications of paragonimiasis, some of which may require surgical interventions. PMID:23824370

  13. Paragonimus kellicotti: A Lung Infection in Our Own Backyard

    Directory of Open Access Journals (Sweden)

    Eric Johannesen

    2016-01-01

    Full Text Available Paragonimiasis is an infection caused by the lung fluke of the genus Paragonimus. Within the United States, paragonimiasis has been commonly diagnosed in Southeast Asian immigrants infected with the Asian lung fluke Paragonimus westermani. Infections from the North American lung fluke, Paragonimus kellicotti, have been rare, although more infections have been seen in people in the Midwestern United States. A 29-year-old male with a history of pleomorphic xanthoastrocytoma presented with hemoptysis. A CT scan showed a mass in the left upper lung lobe. A biopsy showed eosinophils and parasite eggs, some with a recognizable operculum. Further investigation revealed that he takes canoe trips on rivers within Missouri and would eat crayfish caught from these rivers. A blood sample was confirmed positive for Paragonimiasis serologically at the Center for Disease Control. Paragonimus kellicotti is found in rivers within the Mississippi basin. Infection occurs by consuming uncooked or undercooked crawfish. Microscopic identification of parasite eggs has been the gold standard. Serologic tests have been developed to aid in the diagnosis. Patients typically present with fever and hemoptysis. Common CT findings include pleural effusion, a mass, and lymphadenopathy. Awareness of P. kellicotti is important to guide appropriate diagnostic testing and ensuring proper treatment.

  14. COMPARISON BETWEEN INDIVIDUAL AND GROUP MATING OF AUSTROPOTAMOBIUS PALLIPESUNDER CONTROLLED CONDITIONS

    Directory of Open Access Journals (Sweden)

    SÁEZ-ROYUELA M.

    2005-07-01

    Full Text Available Individual mating was compared with mating in groups under laboratory conditions using 64 females and 32 males of white–clawed crayfish (Austropotamobius pallipes. Mating in groups took place at a density of 24 animals/m2 placed in two 1m2 fibreglass tanks (16 females and 8 males/tank. Individual pairing was made in net plastic cubic boxes of 0.25 × 0.25 m bottom surface placed in 1m2 fibreglass tanks (8 boxes/tank. Percentages of mating and spawning were similar in both treatments (100 and 93.7% in groups and 96.9 and 93.7% in individual pairing. However, pleopodal egg number and survival rate 78 days after spawning (phase VIII-IX of embryonic development were higher in females mated in groups (67 and 57.4% than those individually inseminated (26 and 25.9%. Possible causes of lower egg survival rate of individually mated females are discussed.

  15. Standard Guide for Irradiation of Finfish and Aquatic Invertebrates Used as Food to Control Pathogens and Spoilage Microorganisms

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This guide outlines procedures and operations for the irradiation of raw, untreated, fresh (chilled), or frozen finfish and aquatic invertebrates, while ensuring that the irradiated product is safe and wholesome. 1.1.1 Aquatic invertebrates include molluscs, crustacea, echinoderms, etc. 1.1.1.1 Molluscs include bivalve shellfish, such as clams, mussels, and oysters; snails; and cephalopods, such as squid and octopus. 1.1.1.2 Crustacea include shellfish such as shrimp, lobster, crabs, prawns and crayfish. 1.1.1.3 Echinoderms include sea urchins and sea cucumbers. 1.2 This guide covers absorbed doses used to reduce the microbial and parasite populations in aquatic invertebrates and finfish. Such doses typically are below 10 kGy (1). 1.3 The use of reduced-oxygen packaging (vacuum or modified atmosphere, and including products packed in oil) with irradiated, raw product is not covered by this guide. The anaerobic environment created by reduced-oxygen packaging provides the potential for outgrowth o...

  16. The B vitamins nicotinamide (B3) and riboflavin (B2) stimulate metamorphosis in larvae of the deposit-feeding polychaete Capitella teleta: implications for a sensory ligand-gated ion channel.

    Science.gov (United States)

    Burns, Robert T; Pechenik, Jan A; Biggers, William J; Scavo, Gia; Lehman, Christopher

    2014-01-01

    Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1-2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae.

  17. Molecular evidence for high frequency of multiple paternity in a freshwater shrimp species Caridina ensifera.

    Directory of Open Access Journals (Sweden)

    Gen Hua Yue

    2010-09-01

    Full Text Available Molecular genetic analyses of parentage provide insights into mating systems. Although there are 22,000 members in Malacostraca, not much has been known about mating systems in Malacostraca. The freshwater shrimp Caridina ensifera blue, is a new species belonging to Malacostraca which was discovered recently in Sulawesi, Indonesia. Due to its small body size and low fecundity, this species is an ideal species to study the occurrence and frequency of multiple paternity and to understand of how the low fecundity species persist and evolve.In this study, we developed four polymorphic microsatellites from C. ensifera and applied them to investigate the occurrence and frequency of multiple paternity in 20 C. ensifera broods caught from Lake Matano, Sulawesi. By genotyping the mother and all offspring from each brood we discovered multiple paternity in all 20 broods. In most of the 20 broods, fathers contributed skewed numbers of offspring and there was an apparent inverse correlation between reproductive success of sires and their relatedness to mothers.Our results in combination with recent reports on multiple paternity in crayfish, crab and lobster species suggests that multiple paternity is common in Malacostraca. Skewed contribution of fathers to the numbers of offspring and inverse correlation between reproductive success of sires and their relatedness to mothers suggest that sperm competition occurred and/or pre- and postcopulatory female choice happen, which may be important for avoiding the occurrence of inbreeding and optimize genetic variation in offspring and for persistence and evolution of low fecundity species.

  18. Effects of pond draining on biodiversity and water quality of farm ponds.

    Science.gov (United States)

    Usio, Nisikawa; Imada, Miho; Nakagawa, Megumi; Akasaka, Munemitsu; Takamura, Noriko

    2013-12-01

    Farm ponds have high conservation value because they contribute significantly to regional biodiversity and ecosystem services. In Japan pond draining is a traditional management method that is widely believed to improve water quality and eradicate invasive fish. In addition, fishing by means of pond draining has significant cultural value for local people, serving as a social event. However, there is a widespread belief that pond draining reduces freshwater biodiversity through the extirpation of aquatic animals, but scientific evaluation of the effectiveness of pond draining is lacking. We conducted a large-scale field study to evaluate the effects of pond draining on invasive animal control, water quality, and aquatic biodiversity relative to different pond-management practices, pond physicochemistry, and surrounding land use. The results of boosted regression-tree models and analyses of similarity showed that pond draining had little effect on invasive fish control, water quality, or aquatic biodiversity. Draining even facilitated the colonization of farm ponds by invasive red swamp crayfish (Procambarus clarkii), which in turn may have detrimental effects on the biodiversity and water quality of farm ponds. Our results highlight the need for reconsidering current pond management and developing management plans with respect to multifunctionality of such ponds. Efectos del Drenado de Estanques sobre la Biodiversidad y la Calidad del Agua en Estanques de Cultivo. © 2013 Society for Conservation Biology.

  19. Rapid Change of Microbiota Diversity in the Gut but Not the Hepatopancreas During Gonadal Development of the New Shrimp Model Neocaridina denticulata.

    Science.gov (United States)

    Cheung, Man Kit; Yip, Ho Yin; Nong, Wenyan; Law, Patrick Tik Wan; Chu, Ka Hou; Kwan, Hoi Shan; Hui, Jerome Ho Lam

    2015-12-01

    During evolution of animals, their co-evolution with bacteria has generally been ignored. Recent studies have provided evidences that the symbiotic bacteria in the animal gut can either be essential or contributing to the plasticity of the host. The Crustacea includes crab, crayfish, lobster, and shrimp and represents the second largest subphylum on the planet. Although there are already studies investigating the intestinal bacterial communities in crustaceans, none of them has examined the microbiota in different parts of the digestive system during the gonad development of the host. Here, we utilized a new shrimp model Neocaridina denticulata and sequenced the 16S rRNA using the Ion Torrent platform to survey the bacterial populations colonizing the hepatopancreas, foregut, and intestine, including midgut and hindgut, of the early, mid, and late ovarian maturation stages of the shrimp. The predominant bacteria phylum was found to be Proteobacteria, with more than 80 % reads from the gut flora at the early gonad development belonged to a Coxiella-type bacterium. Distinct bacterial communities can be detected between the hepatopancreas and gut, although no significant difference could be revealed between the different regions of the gut investigated. Surprisingly, during the gonad development, bacterial diversity changed rapidly in the gut but not the hepatopancreas. This study provides the first evidence that microbiota modified differentially in specific regions of the digestive tract during gonadal development of crustaceans.

  20. Keanekaragaman dan Potensi Lobster (Malacostraca: Palinuridae di Pantai Pameungpeuk, Garut Selatan, Jawa Barat

    Directory of Open Access Journals (Sweden)

    Rianta Pratiwi

    2018-01-01

    Full Text Available Coral shrimp (Panulirus spp. or known as lobster is a potential fishery commodity and economic value. The demand for domestic and export market continues to increase both as local consumption and export. Indonesia is the largest lobster fishery producer in almost all Indonesian waters, from the west coast of Sumatra to the east coast Jayapura, one of which is Pameungpeuk beach, South Garut, West Java. As a result of increasing demand, fishermen try to catch as many lobsters and the impact of lobster prices also in creases and whereas fishermen continuously take it from nature. This study was conducted to determine the diversity and potential of lobster species especially living in high wavy waters along the southern coast of Garut (Pamengpeuk, West Java.The results of observation are only three types of crayfish, namely: a. Panulirus homarus (green lobster sand; b. Panulirus longipes (lobster flower/ red lobster and Panulirus versicolor (green lobster/bamboo; is most commonly found in the area of south Garut, Pameungpeuk beach with high and strong waves. The percentage of female P longipes species (42.88% was higher compared to male P. homarus (40% and ovigerous female of P. versicolor (37.14%. While the sexual ratio between P. homarus (1:2.0:2.0; P. longipes (1:1.2:1.0 and P. versicolor: 1:1.2:1.2  which statistically showed significantly different p <0.05.

  1. Experimental mineralization of crustacean eggs: new implications for the fossilization of Precambrian–Cambrian embryos

    Directory of Open Access Journals (Sweden)

    D. Hippler

    2012-05-01

    Full Text Available Phosphatized globular microfossils from the Ediacaran and lower Cambrian of South China represent an impressive record of early animal evolution and development. However, their phylogenetic affinity is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are crucial for a reliable interpretation of their phylogenetic position. We conducted phosphatization experiments on eggs of the marbled crayfish Procambarus that indicate a close link between early mineralization and rapid anaerobic decay of the endochorional envelope. Our experiments replicated the different preservational stages of degradation observed in the fossil record. Stabilization of the spherical morphology was achieved by pre-heating of the eggs. Complete surface mineralization occurred under reduced conditions within one to two weeks, with fine-grained brushite (CaHPO4 · 2H2O and calcite. The mechanisms of decay, preservation of surface structures, and mineral replacement in the experiment were likely similar during fossilization of Cambrian embryos.

  2. The Behavior of Chromosomes During Parthenogenetic Oogenesis in Marmorkrebs Procambarus fallax f. virginalis.

    Science.gov (United States)

    Kato, Miku; Hiruta, Chizue; Tochinai, Shin

    2016-08-01

    Parthenogenetic oogenesis varies among and even within species. Based on cytological mechanisms, it can largely be divided into apomixis (ameiotic parthenogenesis) producing genetically identical progeny, and automixis (meiotic parthenogenesis) producing genetically non-identical progeny. Polyploidy is common in parthenogenetic species, although the association between parthenogenesis and polyploidy throughout evolution is poorly understood. Marmorkrebs, or the marbled crayfish, was first identified as a parthenogenetic decapod and was tentatively named as Procambarus fallax f. virginalis. Previous studies revealed that Marmorkrebs is triploid and produces genetically identical offspring, suggesting that apomixis occurs during parthenogenetic oogenesis. However, the behavior of chromosomes during the process of oogenesis is still not well characterized. In this study, we observed parthenogenetic oogenesis around the time of ovulation in P. fallax f. virginalis by histology and immunohistochemistry. During oogenesis, the chromosomes were separated into two groups and behaved independently from each other, and one complete division corresponding to mitosis (the second meiosis-like division) was observed. This suggests that parthenogenetic oogenesis in Marmorkrebs exhibits gonomery, a phenomenon commonly found in apomictic parthenogenesis in polyploid animals.

  3. Quantifying foodweb interactions with simultaneous linear equations: Stable isotope models of the Truckee River, USA

    Science.gov (United States)

    Saito, L.; Redd, C.; Chandra, S.; Atwell, L.; Fritsen, C.H.; Rosen, Michael R.

    2007-01-01

    Aquatic foodweb models for 2 seasons (relatively high- [March] and low-flow [August] conditions) were constructed for 4 reaches on the Truckee River using ??13C and ??15N data from periphyton, macroinvertebrate, and fish samples collected in 2003 and 2004. The models were constructed with isotope values that included measured periphyton signatures and calculated mean isotope values for detritus and seston as basal food sources of each food web. The pseudo-optimization function in Excel's Solver module was used to minimize the sum of squared error between predicted and observed stable-isotope values while simultaneously solving for diet proportions for all foodweb consumers and estimating ??13C and ??15N trophic enrichment factors. This approach used an underdetermined set of simultaneous linear equations and was tested by running the pseudo-optimization procedure for 500 randomly selected sets of initial conditions. Estimated diet proportions had average standard deviations (SDs) of 0.03 to 0.04??? and SDs of trophic enrichment factors ranged from dead ends because they generally were not consumed. Predatory macroinvertebrate diets varied along the river and affected estimated trophic positions of fish that consumed them. Differences in complexity and composition of the food webs appeared to be related to season, but could also have been caused by interactions with nonnative species, especially invasive crayfish. ?? 2007 by The North American Benthological Society.

  4. Speciation and bioavailability of Americium-241 in the fresh water environment

    International Nuclear Information System (INIS)

    Bierkens, J.

    1986-01-01

    Due to its anthropogenic origin, the transuranic americium 241 confronts physiologists with the intriguing question, which mechanisms are involved in the incorporation or elimination of such artificial elements in biological cycles. The investigations on the speciation and bioavailability of 241 Am in the freshwater environment aim to establish a relation between the behavior of 241 Am in freshwater ecosystems and its availability for biota. In the limnic environment, most often characterized by a high organic load and a low conductivity, the effect of complexation of 241 Am with humic acids and competition with trivalent cations such as A1 and Fe, were proven to be significant on the speciation of 241 Am. Based on the registration of the 241 Am uptake by a large number of freshwater organisms, the crayfish Astacus leptodactylus Eschscholtz was chosen to study the whole-body uptake of 241 Am, its corresponding organ distribution and its retention in the animal. The share of external fixation and ingestion in the global uptake, and the effect of speciation on it, were studied more carefully. Other aspects in this physiological part were: the kinetics of 241 Am in the hemolymph and the hepatopancreas, and its subcellular distribution in the digestive gland. Finally, by comparing the physiology of 241 Am with some other metals ( 240 Pu, 64 Cu, 198 Au) with analogous or contradictional properties, we tried to find out whether the behavior of 241 Am in organisms can be explained from its chemical characteristics

  5. Deep insight into white spot syndrome virus vaccines: A review

    Directory of Open Access Journals (Sweden)

    MA Badhul Haq

    2012-02-01

    Full Text Available White spot syndrome virus (WSSV, the causative virus of the disease, is found in most shrimp farming areas of the world, where it causes large economic losses to the shrimp farming industry. The potentially fatal virus has been found to be a threat not only to all shrimp species, but also to other marine and freshwater crustaceans, such as crab and crayfish. To date, no effective prophylactic treatment measures are available for viral infections in shrimp and other crustaceans. Due to current aquaculture practices and the broad host range of WSSV, intervention strategies including vaccination against this virus would be pivotal to save and protect shrimp farming. Several achievements have been attained in the search of novel vaccines for WSSV. DNA vaccination, recombinant vaccines, oral vaccination techniques and gene therapy are some of the thrust areas of focus for scientists and researchers. This review article highlights the recent trends in the development of WSSV vaccines either as DNA vaccines or recombinant vaccines and their functioning strategies as suggested by the researchers worldwide.

  6. Comparative ultrastructure of spermatozoa of the redclaw Cherax quadricarinatus and the yabby Cherax destructor (Decapoda, Parastacidae).

    Science.gov (United States)

    Kouba, Antonín; Niksirat, Hamid; Bláha, Martin

    2015-02-01

    Ultrastructure of spermatozoa of redclaw Cherax quadricarinatus and yabby Cherax destructor were described and compared. The acrosome complex and nucleus are located at the anterior and posterior region of the spermatozoon, respectively. The acrosome is a complex vesicle divided into two parts: the main body of the acrosome appears as a dense cup-shaped structure in longitudinal sagittal view, with the subacrosome zone occupying the central area of the vesicle. The acrosome is larger in C. quadricarinatus (width 2.37±0.27μm, length 1.31±0.23μm) than in C. destructor (width 1.80±0.27μm, length 1.01±0.15μm). There was no significant difference in L:W ratios of the studied species. The subacrosome zone in both species consists of two areas of different electron density. The nucleus is substantially decondensed and irregular in shape, with elaborate extended processes. The examined species exhibited a well-conserved structure of crayfish spermatozoon, similar to those of Cherax cainii and Cherax albidus. Small acrosome size, the absence of radial arms, and an extracellular capsule seem to be the morphological features that mostly distinguish Cherax from the Astacidae and Cambaridae. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. A new photosensory function for simple photoreceptors, the intrinsically photoresponsive neurons of the sea slug Onchidium

    Directory of Open Access Journals (Sweden)

    Tsukasa Gotow

    2009-12-01

    Full Text Available Simple photoreceptors, namely intrinsically light-sensitive neurons without microvilli and/or cilia, have long been known to exist in the central ganglia of crayfish, Aplysia, Onchidium, and Helix. These simple photoreceptors are not only first-order photosensory cells, but also second-order neurons (interneurons, relaying several kinds of sensory synaptic inputs. Another important issue is that the photoresponses of these simple photoreceptors show very slow kinetics and little adaptation. These characteristics suggest that the simple photoreceptors of the Onchidium have a function in non-image-forming vision, different from classical eye photoreceptors used for cording dynamic images of vision. The cited literature provides evidence that the depolarizing and hyperpolarizing photoresponses of simple photoreceptors play a role in the long-lasting potentiation of synaptic transmission of excitatory and inhibitory sensory inputs, and as well as in the potentiation and the suppression of the subsequent behavioral outputs. In short, we suggest that simple photoreceptors operate in the general potentiation of synaptic transmission and subsequent motor output; i.e., they perform a new photosensory function.

  8. Photodynamic therapy-induced nitric oxide production in neuronal and glial cells.

    Science.gov (United States)

    Kovaleva, Vera D; Uzdensky, Anatoly B

    2016-10-01

    Nitric oxide (NO) has been recently demonstrated to enhance apoptosis of glial cells induced by photodynamic therapy (PDT), but to protect glial cells from PDT-induced necrosis in the crayfish stretch receptor, a simple neuroglial preparation that consists of a single mechanosensory neuron enveloped by satellite glial cells. We used the NO-sensitive fluorescent probe 4,5-diaminofluorescein diacetate to study the distribution and dynamics of PDT-induced NO production in the mechanosensory neuron and surrounding glial cells. The NO production in the glial envelope was higher than in the neuronal soma axon and dendrites both in control and in experimental conditions. In dark NO generator, DEA NONOate or NO synthase substrate L-arginine hydrochloride significantly increased the NO level in glial cells, whereas NO scavenger 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) or inhibitors of NO synthase L-NG-nitro arginine methyl ester and N?-nitro-L-arginine decreased it. PDT induced the transient increase in NO production with a maximum at 4 to 7 min after the irradiation start followed by its inhibition at 10 to 40 min. We suggested that PDT stimulated neuronal rather than inducible NO synthase isoform in glial cells, and the produced NO could mediate PDT-induced apoptosis.

  9. Involvement of nitric oxide in photodynamic injury of neurons and glial cells.

    Science.gov (United States)

    Kovaleva, Vera; Berezhnaya, Elena; Komandirov, Maxim; Rudkovskii, Mikhail; Uzdensky, Anatoly

    2013-02-28

    Photodynamic therapy (PDT) is a potential tool for treatment of brain tumors. However, not only malignant but also healthy neurons and glial cells may be damaged during PDT. Nitric oxide is an important modulator of cell viability and intercellular neuroglial communications. In order to study its role in photodynamic injury of normal neurons and surrounding glial cells, we used the crayfish stretch receptor that consists of only two identified sensory neurons enveloped by glial cells. Photodynamic treatment with alumophthalocyanine Photosens and diode laser (670 nm, 0.4 W/cm(2)) induced firing elimination, necrosis of neurons and glia, and apoptosis of glial cells. NO generated by exogenous generators NONOate or sodium nitroprussside protected neurons and glial cells from PDT-induced necrosis but enhanced PDT-induced apoptosis of glial cells. Application of various inhibitors of NO synthase showed that the anti-necrotic effect of NO could be related, at least in glial cells, to its production by neuronal rather than inducible isoform of this enzyme. Unlike, the pro-apoptotic effect of NO on glial cells could be, at least in part, associated with inducible NO synthase. The proapoptotic effect of NO on glial cells could be mediated by protein kinase G, which is activated by NO-dependent production of cGMP, because it inhibition reduced the PDT-induced glial apoptosis. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Photodynamic therapy-induced nitric oxide production in neuronal and glial cells

    Science.gov (United States)

    Kovaleva, Vera D.; Uzdensky, Anatoly B.

    2016-10-01

    Nitric oxide (NO) has been recently demonstrated to enhance apoptosis of glial cells induced by photodynamic therapy (PDT), but to protect glial cells from PDT-induced necrosis in the crayfish stretch receptor, a simple neuroglial preparation that consists of a single mechanosensory neuron enveloped by satellite glial cells. We used the NO-sensitive fluorescent probe 4,5-diaminofluorescein diacetate to study the distribution and dynamics of PDT-induced NO production in the mechanosensory neuron and surrounding glial cells. The NO production in the glial envelope was higher than in the neuronal soma axon and dendrites both in control and in experimental conditions. In dark NO generator, DEA NONOate or NO synthase substrate L-arginine hydrochloride significantly increased the NO level in glial cells, whereas NO scavenger 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) or inhibitors of NO synthase L-NG-nitro arginine methyl ester and Nω-nitro-L-arginine decreased it. PDT induced the transient increase in NO production with a maximum at 4 to 7 min after the irradiation start followed by its inhibition at 10 to 40 min. We suggested that PDT stimulated neuronal rather than inducible NO synthase isoform in glial cells, and the produced NO could mediate PDT-induced apoptosis.

  11. Historical freshwater fish ecology: a long-term view of distribution changes and biological invasions

    Directory of Open Access Journals (Sweden)

    Miguel Clavero

    2015-12-01

    Full Text Available Past processes and events may have an important influence on contemporaneous ecological patterns, including current human impacts on landscapes and organisms. In spite of that, most of the ecological knowledge has been built upon short-term studies, which very rarely exceed one decade. Ecology and Conservation Biology have an important lack of historical approaches, a deficiency that may become a hindrance for the management of natural systems. In this talk I will present examples of how historical information on the distribution of freshwater fish and other aquatic organisms can be used to address ecological questions. Most analyses are based on two important Spanish historical written sources: the Relaciones de Felipe II (16th century and the Madoz Dictionary (19th century. The examples considered include the European eel (Anguilla anguilla, the brown trout (Salmo trutta, the common carp (Cyprinus carpio and the white clawed crayfish (Austropotamobius italicus, among other species, as well as questions related to biological invasions, habitat loss and the impacts of global warming. The outputs of ecological research based on historical data often become useful tools for present-day biodiversity conservation planning and actions.

  12. Heavy Metals in Seafood and Farm Produce from Uyo, Nigeria; Levels and health implications

    Directory of Open Access Journals (Sweden)

    Orish E. Orisakwe

    2015-05-01

    Full Text Available Objectives: This study aimed to obtain representative data on the levels of heavy metals in seafood and farm produce consumed by the general population in Uyo, Akwa Ibom State, Nigeria, a region known for the exploration and exploitation of crude oil. Methods: In May 2012, 25 food items, including common types of seafood, cereals, root crops and vegetables, were purchased in Uyo or collected from farmland in the region. Dried samples were ground, digested and centrifuged. Levels of heavy metals (lead, cadmium, nickel, cobalt and chromium were analysed using an atomic absorption spectrophotometer. Average daily intake and target hazard quotients (THQ were estimated. Results: Eight food items (millet, maize, periwinkle, crayfish, stock fish, sabina fish, bonga fish and pumpkin leaf had THQ values over 1.0 for cadmium, indicating a potential health risk in their consumption. All other heavy metals had THQ values below 1.0, indicating insignificant health risks. The total THQ for the heavy metals ranged from 0.389 to 2.986. There were 14 items with total THQ values greater than 1.0, indicating potential health risks in their consumption. Conclusion: The regular consumption of certain types of farm produce and seafood available in Uyo, Akwa Ibom State, Nigeria, is likely adding to the body burden of heavy metals among those living in this region.

  13. Culturally significant fisheries: keystones for management of freshwater social-ecological systems

    Directory of Open Access Journals (Sweden)

    Mae Noble

    2016-06-01

    Full Text Available Indigenous peoples of North America, Australia, and New Zealand have a long tradition of harvesting freshwater animals. Over generations of reliance and subsistence harvesting, Indigenous peoples have acquired a profound understanding of these freshwater animals and ecosystems that have become embedded within their cultural identity. We have identified trans-Pacific parallels in the cultural significance of several freshwater animal groups, such as eels, other finfish, bivalves, and crayfish, to Indigenous peoples and their understanding and respect for the freshwater ecosystems on which their community survival depends. In recognizing such cultural connections, we found that non-Indigenous peoples can appreciate the deep significance of freshwater animals to Indigenous peoples and integrate Indigenous stewardship and Indigenous ecological knowledge into effective comanagement strategies for sustainable freshwater fisheries, such as Indigenous rangers, research partnerships, and Indigenous Protected Areas. Given that many of these culturally significant freshwater species also play key ecological roles in freshwater ecosystems, their recognition and prioritization in management and monitoring approaches should help sustain the health and well-being of both the social and ecological components of freshwater ecosystems.

  14. Shoreline urbanization interrupts allochthonous subsidies to a benthic consumer over a gradient of lake size.

    Science.gov (United States)

    Larson, Eric R; Olden, Julian D; Usio, Nisikawa

    2011-08-23

    The role of resource subsidies across ecosystem boundaries has emerged as an important concept in contemporary ecology. For lake ecosystems, this has led to interest in quantifying the contribution of terrestrial allochthonous carbon to aquatic secondary production. An inverse relationship between habitat area and the role of allochthonous subsidies has been documented on marine islands and assumed for lakes, yet there have been no tests of this pattern among benthic (lake bottom) consumers. Here, we used carbon stable isotopes to trace terrestrial allochthonous and benthic autochthonous carbon use by the crayfish Pacifastacus leniusculus over a gradient of lake area, productivity and urbanization. Consistent with findings from terrestrial islands, habitat size dictated the importance of allochthonous subsidies, as P. leniusculus transitioned from using predominantly terrestrial carbon in small lakes to an increased reliance on autochthonous production in larger lakes. However, shoreline urbanization interacted with this pattern, particularly for small lakes where greater urbanization resulted in reduced use of allochthonous resources. As such, we provide, to our knowledge, the first confirmation of the predicted relationship between habitat size and importance of allochthonous subsidies to lake benthic consumers, but found that urbanization can interfere with this pattern. This journal is © 2011 The Royal Society

  15. Compact Surface Plasmon Resonance Sensor for Underwater Chemical Sensing Robot

    Directory of Open Access Journals (Sweden)

    Yuichi Minagawa

    2017-01-01

    Full Text Available This paper reports on the development of compact surface plasmon resonance (SPR sensors for mobile robot olfaction. Underwater robots benefit from olfactory sensing capabilities in various tasks including the search for unexploded ordnance and undersea wreckage. Although the SPR-based chemical sensor is a promising sensing platform, the cumbersome optical setup has been limiting its use on mobile robots. The proposed sensor employs a periodic metal structure formed on a self-assembled layer of polystyrene particles of 200 nm in diameter. With the grating of this size, SPR can be excited even with a simple LED light source. The change in the absorbance is simply measured using a photodiode. Demonstration of the proposed SPR sensor is provided by mounting the sensors on an underwater crayfish robot that autonomously searches for a chemical source. The fabricated sensor shows linear response to ascorbic acid for a concentration range from 20 to 80 mM. Responses of the bare and thiol-coated gold nanostructure to different chemical substances are presented to show the change in the selectivity of the sensor by the coating. Discussions are made on the importance of sample collection for the sensor to attain sensitive chemical detection on a mobile robot.

  16. Non-indigenous macroinvertebrate species in Lithuanian fresh waters, Part 1: Distributions, dispersal and future

    Directory of Open Access Journals (Sweden)

    Arbačiauskas K

    2012-01-01

    Full Text Available Biological invasions are of increasing global concern. They impact on biodiversity and may result in high economic loss. This demands improvement in knowledge of the dynamics of species dispersal with the goal of preventing future invasions, and predicting and reducing undesirable impacts. This study reports on non-indigenous macroinvertebrate species (NIMS which have invaded Lithuanian fresh waters. Fifteen NIMS have been recorded during a 12-year study. They include one cnidarian, two molluscan and twelve crustacean species. The deliberate introduction of peracaridans and crayfish for fishery and aquaculture enhancement has substantially contributed to the current NIMS composition. Invaders of Ponto-Caspian origin are dominant, and the collector-gatherers are the largest group with respect to feeding mode. Current NIMS distributions, the history of their primary invasion and patterns of local dispersal are analysed. The main invasion vectors have been inland shipping and deliberate introductions, while secondary spread proceeded both naturally and by various human mediated vectors. The current distribution of most NIMS may remain constant in the future, whilst further expansion of a few NIMS, which possess good dispersal abilities and are well-adapted to freshwater environments, seems very probable. Using multivariate analysis of data from water bodies with established peracaridan invaders, allowed predictions on which unsurveyed water bodies could contain such invaders. Invasions of new NIMS and diversification of donor areas, pathways and vectors are considered.

  17. Freshwater pearl mussels show plasticity of responses to different predation risks but also show consistent individual differences in responsiveness.

    Science.gov (United States)

    Wilson, Conor D; Arnott, Gareth; Elwood, Robert W

    2012-03-01

    Animals often show behavioural plasticity with respect to predation risk but also show behavioural syndromes in terms of consistency of responses to different stimuli. We examine these features in the freshwater pearl mussel. These bivalves often aggregate presumably to reduce predation risk to each individual. Predation risk, however, will be higher in the presence of predator cues. Here we use dimming light, vibration and touch as novel stimuli to examine the trade-off between motivation to feed and motivation to avoid predation. We present two experiments that each use three sequential novel stimuli to cause the mussels to close their valves and hence cease feeding. We find that mussels within a group showed shorter closure times than solitary mussels, consistent with decreased vulnerability to predation in group-living individuals. Mussels exposed to the odour of a predatory crayfish showed longer closures than control mussels, highlighting the predator assessment abilities of this species. However, individuals showed significant consistency in their closure responses across the trial series, in line with behavioural syndrome theory. Our results show that bivalves trade-off feeding and predator avoidance according to predation risk but the degree to which this is achieved is constrained by behavioural consistency. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Subcellular fractionation associated to radionuclide analysis in various tissues: validation of the technique by using light and electron observations applied on gills bivalves and uranium

    Energy Technology Data Exchange (ETDEWEB)

    Camilleri, V.; Simon, O.; Grasset, G. [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

    The metal bioaccumulation levels in target-organs associated with micro-localization approaches at the subcellular level provide information for the understanding of the metabolic metal cycle. These findings could be used to select relevant bio-markers of exposure and to focus on specific contaminated organelles to study potential biological effects. Moreover, the metal accumulated in the cytosol fraction can be bound to macromolecules in order to be eliminated and/or to induce a potential cellular effect. Tissular distribution, transfer efficiency from water and subcellular fractionation were investigated on the freshwater bivalve, Corbicula fluminea after uranium aqueous exposure. The subcellular fractionation was performed while measuring associated uranium to each cellular different fraction as follows: cellular debris and nuclei, mitochondria and lysosomes, membranes, microsomes and cytosol. In our experimental conditions, the accumulation in the cytosol fraction was low and more than 80 % of the total uranium in gills and visceral mass was accumulated in the insoluble fraction. Main results presented in this poster come from light and electron microscope observations of subcellular fractions (nuclei/debris and lysosomes/mitochondria) in order to validate the efficiency of the fractionation technique. An adaptation of the fractionation technique is proposed. This set of data confirms high differences of fractionation efficiency as a function of fractionation technique and organs/biological model used (gills of bivalves, digestive gland of crayfish). (author)

  19. Fast Real-Time PCR for the Detection of Crustacean Allergens in Foods.

    Science.gov (United States)

    Santaclara, Francisco J; Espiñeira, Montserrat

    2017-01-01

    Crustaceans are one of the most common allergens causing severe food reaction. Hypersensitivity reactions associated with seafood intake are one of the most common food allergies in adults. Crustaceans including shrimps, prawns, crabs, lobster, and crayfish are a common cause of anaphylaxis or hypersensitivity, with shrimps and crabs being the most common causes of allergy. Symptoms occur most often when food or cooking water are ingested.These food allergens are a health problem, and they have become very important; as evidenced by the existence of several regulations that establish that labeling must be present regarding these allergens to warn consumers.The methodology herein exposed allows the detection of crustaceans in any type of product, including those where very aggressive treatments of temperature and pressure are used during the manufacturing process.The main features of this method are its high sensitivity and specificity, and reduced analysis time of real-time PCR (40 min). This assay is a potential tool in issues related to the labeling of products and food security to protect the allergic consumer.

  20. Isparta Gülünün (Rosa damascena Mill. Su Ürünlerinde Gıda Katkı Maddesi Olarak Kullanımı: Antimikrobiyel ve Antioksidan Özellikleri Açısından Genel Değerlendirme

    Directory of Open Access Journals (Sweden)

    Abdullah DİLER

    2014-07-01

    Full Text Available Rose species have significant place among ornemantal flowers. Nowadays, the members of the family of Rosaceae are used in foods and for medical purposes. The members of this family have significant physiological functions due to their phenolic compounds richness (citronellol, graniol and nerol. Phenolic compounds acts as antioxidant, free radical scvenger, anti-cancer, anti-inflammatory, anti-mutegenic, anti-depresant and antibacterial. Fresh sea foods have relatively short shelf-life. In this context economical loses could be raised and increased losses could be in long distences. Nowadays, essential oils are used in processing technologies. Frequently used essential oils in sea foods are thyme, laurel, apple, clove and generally used as antioxidant and antimicrobial additives. The favorable results were presented in the literature in terms of usage of the essential oils as antibacterial agent against food pathogens. Additionally, decelerated lipid oxidation in the case of usage of essentials oils compared to synthetical antioxidants. Isparta has significant place in terms of the production of fresh water fish (carp, rainbow trout, and pike perch and crayfish. Fresh water fish are generally marketed fresh for the consumption. Even though there is no available information about the usage of rose extract in sea foods, by taking into

  1. Unconventional amino acid sequence of the sun anemone (Stoichactis helianthus) polypeptide neurotoxin

    International Nuclear Information System (INIS)

    Kem, W.; Dunn, B.; Parten, B.; Pennington, M.; Price, D.

    1986-01-01

    A 5000 dalton polypeptide neurotoxin (Sh-NI) purified by G50 Sephadex, P-cellulose, and SP-Sephadex chromatography was homogeneous by isoelectric focusing. Sh-NI was highly toxic to crayfish (LD 50 0.6 μg/kg) but without effect upon mice at 15,000 μg/kg (i.p. injection). The reduced, 3 H-carboxymethylated toxin and its fragments were subjected to automatic Edman degradation and the resulting PTH-amino acids were identified by HPLC, back hydrolysis, and scintillation counting. Peptides resulting from proteolytic (clostripain, staphylococcal protease) and chemical (tryptophan) cleavage were sequenced. The sequence is: AACKCDDEGPDIRTAPLTGTVDLGSCNAGWEKCASYYTIIADCCRKKK. This sequence differs considerably from the homologous Anemonia and Anthopleura toxins; many of the identical residues (6 half-cystines, G9, P10, R13, G19, G29, W30) are probably critical for folding rather than receptor recognition. However, the Sh-NI sequence closely resembles Radioanthus macrodactylus neurotoxin III and r. paumotensis II. The authors propose that Sh-NI and related Radioanthus toxins act upon a different site on the sodium channel

  2. Quantification of neurotoxin BMAA (β-N-methylamino-L-alanine) in seafood from Swedish markets

    Science.gov (United States)

    Jiang, Liying; Kiselova, Nadezda; Rosén, Johan; Ilag, Leopold L.

    2014-11-01

    The neurotoxin β-N-methylamino-L-alanine (BMAA) produced naturally by cyanobacteria, diatoms and dinoflagellates can be transferred and accumulated up the food chain, and may be a risk factor for neurodegenerative diseases. This study provides the first systematic screening of BMAA exposure of a large population through the consumption of seafood sold in metropolitan markets. BMAA was distinguished from known isomers by liquid chromatography tandem mass spectrometry after acidic hydrolysis and derivatization. Using deuterium-labeled internal standard, BMAA was quantified as 0.01-0.90 μg/g wet weight of tissues in blue mussel, oyster, shrimp, plaice, char and herring, but was undetectable (<0.01 μg/g) in other samples (salmon, cod, perch and crayfish). Provided that the content of BMAA detected is relevant for intake calculations, the data presented may be used for a first estimation of BMAA exposure through seafood from Swedish markets, and to refine the design of future toxicological experiments and assessments.

  3. Photodynamic impact induces ischemic tolerance in models in vivo and in vitro

    Science.gov (United States)

    Demyanenko, Svetlana; Sharifulina, Svetlana; Berezhnaya, Elena; Kovaleva, Vera; Neginskaya, Maria; Zhukovskaya, Ludmila

    2016-04-01

    Ischemic tolerance determines resistance to lethal ischemia gained by a prior sublethal stimulus (i.e., preconditioning). We reproduced this effect in two variants. In vitro the preliminary short (5 s) photodynamic treatment (PDT) (photosensitizer Photosens, 10 nM, 30 min preincubation; laser: 670 nm, 100 mW/cm2) significantly reduced the necrosis of neurons and glial cells in the isolated crayfish stretch receptor, which was caused by following 30-min PDT by 66% and 46%, respectively. In vivo PDT of the rat cerebral cortex with hydrophilic photosensitizer Rose Bengal (i.v. administration, laser irradiation: 532 nm, 60 mW/cm2, 3 mm beam diameter, 30 min) caused occlusion of small brain vessels and local photothrombotic infarct (PTI). It is a model of ischemic stroke. Cerebral tissue edema and global necrosis of neurons and glial cells occurred in the infarction core, which was surrounded by a 1.5 mm transition zone, penumbra. The maximal pericellular edema, hypo- and hyperchromia of neurons were observed in penumbra 24 h after PTI. The repeated laser irradiation of the contralateral cerebral cortex also caused PTI but lesser as compared with single PDT. Preliminary unilateral PTI provided ischemic tolerance: at 14 day after second exposure the PTI volume significantly decreased by 24% than in the case of a single exposure. Sensorimotor deficits in PDT-treated rats was registered using the behavioral tests. The preliminary PTI caused the preconditioning effect.

  4. A semi-automated method of monitoring dam passage of American Eels Anguilla rostrata

    Science.gov (United States)

    Welsh, Stuart A.; Aldinger, Joni L.

    2014-01-01

    Fish passage facilities at dams have become an important focus of fishery management in riverine systems. Given the personnel and travel costs associated with physical monitoring programs, automated or semi-automated systems are an attractive alternative for monitoring fish passage facilities. We designed and tested a semi-automated system for eel ladder monitoring at Millville Dam on the lower Shenandoah River, West Virginia. A motion-activated eel ladder camera (ELC) photographed each yellow-phase American Eel Anguilla rostrata that passed through the ladder. Digital images (with date and time stamps) of American Eels allowed for total daily counts and measurements of eel TL using photogrammetric methods with digital imaging software. We compared physical counts of American Eels with camera-based counts; TLs obtained with a measuring board were compared with TLs derived from photogrammetric methods. Data from the ELC were consistent with data obtained by physical methods, thus supporting the semi-automated camera system as a viable option for monitoring American Eel passage. Time stamps on digital images allowed for the documentation of eel passage time—data that were not obtainable from physical monitoring efforts. The ELC has application to eel ladder facilities but can also be used to monitor dam passage of other taxa, such as crayfishes, lampreys, and water snakes.

  5. DNA interaction, antitumor and antimicrobial activities of three-dimensional chitosan ring produced from the body segments of a diplopod.

    Science.gov (United States)

    Kaya, Murat; Akyuz, Bahar; Bulut, Esra; Sargin, Idris; Tan, Gamze; Erdonmez, Demet; Maheta, Mansi; Satkauskas, Saulius; Mickevičius, Saulius

    2016-08-01

    Commercially available chitins and the chitin isolated from mushrooms, insect cuticles, shells of shrimp, crab and crayfish reported in the literature are in forms of powder, flake or granule. Three-dimensional chitins have been only known from the sponges but still three-dimensional chitosan has not been reported yet. In this study, we produced three-dimensional chitin and chitosan rings from the body segments of a diplopod species (Julus terrestris). Obtained chitin and chitosan rings were characterized (by FT-IR, SEM, TGA, XRD, dilute solution viscometry and EA) and compared with commercial chitin and chitosan. The interactions with plasmid DNA was studied at varying concentrations of chitosan (0.04, 0.4 and 4mg/mL). Antitumor activity tests were conducted (L929 and HeLa), low cytotoxicity and high antiproliferative activity was observed. Antimicrobial activities of J. terrestris chitosan were investigated on twelve microorganisms and maximum inhibition (15.6±1.154mm) was recorded for common human pathogen Staphylococcus aureus. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. The fungi: 1, 2, 3 ... 5.1 million species?

    Science.gov (United States)

    Blackwell, Meredith

    2011-03-01

    Fungi are major decomposers in certain ecosystems and essential associates of many organisms. They provide enzymes and drugs and serve as experimental organisms. In 1991, a landmark paper estimated that there are 1.5 million fungi on the Earth. Because only 70000 fungi had been described at that time, the estimate has been the impetus to search for previously unknown fungi. Fungal habitats include soil, water, and organisms that may harbor large numbers of understudied fungi, estimated to outnumber plants by at least 6 to 1. More recent estimates based on high-throughput sequencing methods suggest that as many as 5.1 million fungal species exist. Technological advances make it possible to apply molecular methods to develop a stable classification and to discover and identify fungal taxa. Molecular methods have dramatically increased our knowledge of Fungi in less than 20 years, revealing a monophyletic kingdom and increased diversity among early-diverging lineages. Mycologists are making significant advances in species discovery, but many fungi remain to be discovered. Fungi are essential to the survival of many groups of organisms with which they form associations. They also attract attention as predators of invertebrate animals, pathogens of potatoes and rice and humans and bats, killers of frogs and crayfish, producers of secondary metabolites to lower cholesterol, and subjects of prize-winning research. Molecular tools in use and under development can be used to discover the world's unknown fungi in less than 1000 years predicted at current new species acquisition rates.

  7. Training Lymnaea in the presence of a predator scent results in a long-lasting ability to form enhanced long-term memory.

    Science.gov (United States)

    Forest, Jeremy; Sunada, Hiroshi; Dodd, Shawn; Lukowiak, Ken

    2016-06-01

    Lymnaea exposed to crayfish effluent (CE) gain an enhanced ability to form long-term memory (LTM). We test the hypothesis that a single CE exposure and operant conditioning training leads to long lasting changes in the capability of snails to form LTM when tested in pond water four weeks later. We trained both juvenile and adult snails with a single 0.5 h training session in CE and show that LTM was present 24 h later. Snails trained in a similar manner in just pond water show no LTM. We then asked if such training in CE conferred enhanced memory forming capabilities on these snails four weeks later. That is, would LTM be formed in these snails four weeks later following a single 0.5 h training session in pond water? We found that both adult and juvenile snails previously trained in CE one month previously had enhanced LTM formation abilities. The injection of a DNA methylation blocker, 5-AZA, prior to training in adult snails blocked enhanced LTM formation four weeks later. Finally, this enhanced LTM forming ability was not passed on to the next generation of snails.

  8. 'Different strokes for different folks': geographically isolated strains of Lymnaea stagnalis only respond to sympatric predators and have different memory forming capabilities.

    Science.gov (United States)

    Orr, Michael V; Hittel, Karla; Lukowiak, Ken

    2009-07-01

    Gaining insight into how natural trait variation is manifest in populations shaped by differential environmental factors is crucial to understanding the evolution, ecology and sensory biology of natural populations. We have demonstrated that lab-reared Lymnaea detect and respond to the scent of a crayfish predator with specific, appropriate anti-predator behavioral responses, including enhanced long-term memory (LTM) formation, and that such predator detection significantly alters the electrophysiological activity of RPeD1, a neuron that is a necessary site for LTM formation. Here we ask: (1) do distinct populations of wild Lymnaea stagnalis respond only to sympatric predators and if so, can these traits be quantified at both the behavioral and neurophysiological levels, and (2) does the presence of a non-sympatric predator elicit anti-predator behaviors including augmentation of LTM? We tested three different populations of wild (i.e. not lab-reared) snails freshly collected from their natural habitat: (1) polders near Utrecht in The Netherlands, (2) six seasonally isolated ponds in the Belly River drainage in southern Alberta, Canada and (3) a 20-year-old human-made dugout pond in southern Alberta. We found strain-specific variations in the ability to form LTM and that only a sympatric predator evoked anti-predatory behaviors, including enhanced LTM formation and changes in RPeD1 activity.

  9. Conservation status of freshwater gastropods of Canada and the United States

    Science.gov (United States)

    Johnson, Paul D.; Bogan, Arthur E.; Brown, Kenneth M.; Burkhead, Noel M.; Cordeiro, James R.; Garner, Jeffrey T.; Hartfield, Paul D.; Lepitzki, Dwayne A.; Mackie, Gerry L.; Pip, Eva; Tarpley, Thomas A.; Tiemann, Jeremy S.; Whelan, Nathan V.; Strong, Ellen E.

    2013-01-01

    This is the first American Fisheries Society conservation assessment of freshwater gastropods (snails) from Canada and the United States by the Gastropod Subcommittee (Endangered Species Committee). This review covers 703 species representing 16 families and 93 genera, of which 67 species are considered extinct, or possibly extinct, 278 are endangered, 102 are threatened, 73 are vulnerable, 157 are currently stable, and 26 species have uncertain taxonomic status. Of the entire fauna, 74% of gastropods are imperiled (vulnerable, threatened, endangered) or extinct, which exceeds imperilment levels in fishes (39%) and crayfishes (48%) but is similar to that of mussels (72%). Comparison of modern to background extinction rates reveals that gastropods have the highest modern extinction rate yet observed, 9,539 times greater than background rates. Gastropods are highly susceptible to habitat loss and degradation, particularly narrow endemics restricted to a single spring or short stream reaches. Compilation of this review was hampered by a paucity of current distributional information and taxonomic uncertainties. Although research on several fronts including basic biology, physiology, conservation strategies, life history, and ecology are needed, systematics and curation of museum collections and databases coupled with comprehensive status surveys (geographic limits, threat identification) are priorities.

  10. Evaluating the non-lethal effects of organophosphorous and carbamate insecticides on the yabby (Cherax destructor) using cholinesterase (AChE, BChE), Glutathione S-Transferase and ATPase as biomarkers.

    Science.gov (United States)

    Pham, Ben; Miranda, Ana; Allinson, Graeme; Nugegoda, Dayanthi

    2017-09-01

    The toxicity of two organophosphorus insecticides, chlorpyrifos (CPF), malathion (MAL), and one carbamate insecticide, methomyl (METH), to the yabby (Cherax destructor) was assessed by measuring cholinesterase (AChE, BChE), Glutathione S-Transferase (GST) and Na + /K + ATPase activity after 96h of exposure. Yabbies exposed to all three insecticides at 2 and 5µgL -1 exhibited significant AChE, BChE, GST and Na + /K + ATPase inhibition. Based on these enzyme inhibition tests, the toxicity of the three insecticides to C. destructor was CPF > MAL > METH. After 14 days of recovery the yabbies enzymatic activities of AChE, BChE, GST and Na + /K + ATPase was measured. Recovery of The enzyme activity recovery was faster after the exposure to METH than for the yabbies exposed to CPF and MAL. Slow recovery of enzyme activity could affect the physical activities of organisms and produce indirect effects on populations if such crayfish are less able to elude predators or search for food. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Twenty-five-year study of radionuclides in the Susquehanna river via periphyton biomonitors.

    Science.gov (United States)

    Patrick, Ruth; Palms, John; Kreeger, Danielle; Harris, Charles

    2007-01-01

    This 25-y study monitored aquatic and terrestrial gamma-ray-emitting radionuclide levels near a nuclear power plant. It is the only known, long-term environmental survey of its kind. It was conducted neither by a utility owner, nor by a government agency, but rather by a private, environmental research institution. Compared to dozens of other flora and fauna, periphyton was found to be the best indicator to biomonitor the Susquehanna River, which runs near PPL Susquehanna's nuclear plant. Sampling began in 1979 before the first plant start-up and continued for the next 24 years. Monitoring began two months after the Three Mile Island accident of 28 March 1979 and includes Three Mile Island area measurements. Ongoing measurements detected fallout from Chernobyl in 1986, as well as I not released from PPL Susquehanna. Although this paper concentrates on radionuclides found in periphyton, the scope of the entire environmental program includes a wide variety of aquatic and land-based plants, animals, and inorganic matter. Other species and matter studied were fish, mussels, snails, crayfish, insects, humus, mushrooms, lichens, squirrels, deer, cabbage, tomatoes, coarse and flocculated sediment, and more. Results show periphyton works well for detection of radionuclide activity, even in concentrations less than 100 Bq kg (picocuries per gram amounts). Data indicate that PPL Susquehanna's radionuclide releases have had no known environmental or human health impact.

  12. The combined use of chemical and biochemical markers to assess water quality in two low-stream rivers (NE Spain)

    International Nuclear Information System (INIS)

    Fernandes, Denise; Potrykus, Joanna; Morsiani, Cinzia; Raldua, Demetrio; Lavado, Ramon; Porte, Cinta

    2002-01-01

    Carps (Cyprinus carpio) and red swamp crayfish (Procambarus clarkii) were sampled from two low- stream Mediterranean rivers (Anoia and Cardener) receiving extensive urban and industrial waste water discharges. Tissue residues of selected pollutants (organo chlorinated compounds, polycyclic aromatic hydrocarbons (PAHs)) were determined in conjunction with different biochemical responses (cytochrome P450, phase II enzymes) with the aim of investigating whether resident organisms were responsive to changes in water quality. Biota inhabiting those rivers were highly exposed to complex mixtures of polychlorobiphenyls and dichlorodiphenyltrichloroethanes (up to 9 ng/g w.w.) and PAHs (up to 6097 ng/g of hydroxylated PAHs in bile), the highest residues being observed in carps from Cardener. This has a reflection n 7-ethoxyresorufin O-deethylase (EROD) activity; that in carps from ardener ranged between 350 and 550 pmol/min/mg protein, whereas in carps from Anoia ranged between was 90 and 250 pmol/min/mg protein. The highest activity recorded was downstream of the sewage treatment plants in both rivers. Phase II enzymes were less sensitive to pollutant exposure than EROD; nonetheless, both glutathione S-transferase and UDP-glucuronyl transferase ere higher in carps from Cardener. The results support the usefulness of the combined use of chemical and biochemical responses to assess and diagnose pollution in highly stressed ecosystems

  13. Non-Invasive Imaging of Neuroanatomical Structures and Neural Activation with High-Resolution MRI

    Science.gov (United States)

    Herberholz, Jens; Mishra, Subrata H.; Uma, Divya; Germann, Markus W.; Edwards, Donald H.; Potter, Kimberlee

    2011-01-01

    Several years ago, manganese-enhanced magnetic resonance imaging (MEMRI) was introduced as a new powerful tool to image active brain areas and to identify neural connections in living, non-human animals. Primarily restricted to studies in rodents and la