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Sample records for larvae artemia salina

  1. Acute toxicity of furazolidone on Artemia salina, Daphnia magna, and Culex pipiens molestus larvae

    SciTech Connect

    Macri, A.; Stazi, A.V.; Dojmi di Delupis, G.

    1988-10-01

    As a result of evidence of the ecotoxicity of nitrofurans, the acute toxicity of furazolidone was tested in vivo on two aquatic organisms, Artemia salina and Daphnia magna, which are both crustaceans. Toxicity studies were also performed on larvae of Culex pipiens molestus. Results indicated a significant toxicity of the compound on Culex pipiens and Daphnia magna, while Artemia salina proved to be the least sensitive.

  2. Evaluation of Alpha and Gamma Aluminum Oxide Nanoparticle Accumulation, Toxicity and Depuration in Artemia Salina Larvae

    PubMed Central

    Ates, Mehmet; Demir, Veysel; Arslan, Zikri; Daniels, James; Farah, Ibrahim O.; Bogatu, Corneliu

    2014-01-01

    In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity and elimination of α-Al2O3 (50 nm and 3.5 μm) and γ-Al2O3 (5 nm and 0.4 μm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to > 0.3 μm for spherical NPs, and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images revealed that NPs deposited inside the guts as aggregates. ICP-MS analysis showed that large particles (3.5 μm α-Al2O3) were not taken up by Artemia, while fine NPs (0.4 μm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde (MDA) levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 μm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at in all conditions. PMID:24753078

  3. Evaluation of alpha and gamma aluminum oxide nanoparticle accumulation, toxicity, and depuration in Artemia salina larvae.

    PubMed

    Ates, Mehmet; Demir, Veysel; Arslan, Zikri; Daniels, James; Farah, Ibrahim O; Bogatu, Corneliu

    2015-01-01

    In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity, and elimination of α-Al2O3 (50 nm and 3.5 μm) and γ-Al2O3 (5 nm and 0.4 μm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to >0.3 µm for spherical NPs and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images showed that NPs deposited inside the guts as aggregates. Inductively coupled plasma mass spectrometry analysis showed that large particles (3.5 μm α-Al2O3) were not taken up by Artemia, whereas fine NPs (0.4 μm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 µm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at all conditions.

  4. Evaluation of brine shrimp (Artemia salina) larvae as a bioassay for mycotoxins in animal feedstuffs.

    PubMed Central

    Prior, M G

    1979-01-01

    Brine shrimp larvae was tested as a possible simple biological screening system to identify specimens of animal feedstuffs that should be examined further by chemical analytical procedures for mycotoxins. All extracts of the control, nonmouldy feedstuffs increased larval mortality, this being most marked in the case of silage. Chemical and biological testing of diagnostic specimens indicated that the bioassay identified two of four chemically positive specimens and 59 of 135 chemically negative specimens and 59 identified larvicidal compounds present in normal feedstuffs gave a high percentage (56%) of false-positive bioassay results when compared to the results of chemical analyses for three mycotoxins. The use of brine shrimp larvae did not materially reduce the necessity of conducting chemical analyses for mycotoxins. PMID:548157

  5. Primary screening of the bioactivity of brackishwater cyanobacteria: toxicity of crude extracts to Artemia salina larvae and Paracentrotus lividus embryos.

    PubMed

    Lopes, Viviana R; Fernández, Nuria; Martins, Rosário F; Vasconcelos, Vitor

    2010-03-05

    Cyanobacteria are a diverse group of Gram-negative bacteria that produce an array of secondary compounds with selective bioactivity against vertebrates, invertebrates, plants, microalgae, fungi, bacteria, viruses and cell lines. The aim of this study was to assess the toxic effects of aqueous, methanolic and hexane crude extracts of benthic and picoplanktonic cyanobacteria isolated from estuarine environments, towards the nauplii of the brine shrimp Artemia salina and embryos of the sea urchin Paracentrotus lividus. The A. salina lethality test was used as a frontline screen and then complemented by the more specific sea urchin embryo-larval assay. Eighteen cyanobacterial isolates, belonging to the genera Cyanobium, Leptolyngbya, Microcoleus, Phormidium, Nodularia, Nostoc and Synechocystis, were tested. Aqueous extracts of cyanobacteria strains showed potent toxicity against A. salina, whereas in P. lividus, methanolic and aqueous extracts showed embryo toxicity, with clear effects on development during early stages. The results suggest that the brackishwater cyanobacteria are producers of bioactive compounds with toxicological effects that may interfere with the dynamics of invertebrate populations.

  6. Primary Screening of the Bioactivity of Brackishwater Cyanobacteria: Toxicity of Crude Extracts to Artemia salina Larvae and Paracentrotus lividus Embryos

    PubMed Central

    Lopes, Viviana R.; Fernández, Nuria; Martins, Rosário F.; Vasconcelos, Vitor

    2010-01-01

    Cyanobacteria are a diverse group of Gram-negative bacteria that produce an array of secondary compounds with selective bioactivity against vertebrates, invertebrates, plants, microalgae, fungi, bacteria, viruses and cell lines. The aim of this study was to assess the toxic effects of aqueous, methanolic and hexane crude extracts of benthic and picoplanktonic cyanobacteria isolated from estuarine environments, towards the nauplii of the brine shrimp Artemia salina and embryos of the sea urchin Paracentrotus lividus. The A. salina lethality test was used as a frontline screen and then complemented by the more specific sea urchin embryo-larval assay. Eighteen cyanobacterial isolates, belonging to the genera Cyanobium, Leptolyngbya, Microcoleus, Phormidium, Nodularia, Nostoc and Synechocystis, were tested. Aqueous extracts of cyanobacteria strains showed potent toxicity against A. salina, whereas in P. lividus, methanolic and aqueous extracts showed embryo toxicity, with clear effects on development during early stages. The results suggest that the brackishwater cyanobacteria are producers of bioactive compounds with toxicological effects that may interfere with the dynamics of invertebrate populations. PMID:20411110

  7. High surface adsorption properties of carbon-based nanomaterials are responsible for mortality, swimming inhibition, and biochemical responses in Artemia salina larvae.

    PubMed

    Mesarič, Tina; Gambardella, Chiara; Milivojević, Tamara; Faimali, Marco; Drobne, Damjana; Falugi, Carla; Makovec, Darko; Jemec, Anita; Sepčić, Kristina

    2015-06-01

    We investigated the effects of three different carbon-based nanomaterials on brine shrimp (Artemia salina) larvae. The larvae were exposed to different concentrations of carbon black, graphene oxide, and multiwall carbon nanotubes for 48 h, and observed using phase contrast and scanning electron microscopy. Acute (mortality) and behavioural (swimming speed alteration) responses and cholinesterase, glutathione-S-transferase and catalase enzyme activities were evaluated. These nanomaterials were ingested and concentrated in the gut, and attached onto the body surface of the A. salina larvae. This attachment was responsible for concentration-dependent inhibition of larval swimming, and partly for alterations in the enzyme activities, that differed according to the type of tested nanomaterials. No lethal effects were observed up to 0.5mg/mL carbon black and 0.1mg/mL multiwall carbon nanotubes, while graphene oxide showed a threshold whereby it had no effects at 0.6 mg/mL, and more than 90% mortality at 0.7 mg/mL. Risk quotients calculated on the basis of predicted environmental concentrations indicate that carbon black and multiwall carbon nanotubes currently do not pose a serious risk to the marine environment, however if uncontrolled release of nanomaterials continues, this scenario can rapidly change.

  8. Dinucleosidasetetraphosphatase in rat liver and Artemia salina.

    PubMed

    Vallejo, C G; Lobaton, C D; Quintanilla, M; Sillero, A; Sillero, M A

    1976-06-07

    A comparative study of an enzymatic activity present in Artemia salina and rat liver which specifically splits dinucleoside tetraphosphates is presented. All the purine and pyrimidine dinucleoside tetraphosphates tested, i.e. diadenosine, diguanosine, dixanthosine and diuridine tetraphosphates, were substrates of both enzymes with similar maximum velocities and Km values, (around 10 muM). The inhibition by nucleotides of the enzyme from the two sources is also similar. Particularly relevant is the strong inhibition caused by nucleoside tetraphosphates which have Ki values in the nanomolar range. The Artemia enzyme has a slightly lower molecular weight (17 500) than the liver enzyme (21 000) and is more resistant to acidic pH. Based on previous findings, the enzyme from Artemia salina was named diguanosinetetraphosphatase (EC 3.6.1.17) by the Enzyme Commission. The results presented in this paper show that the liver and Artemia enzymes are similar, and we propose to name this enzyme as dinucleosidetetraphosphatase or dinucleoside-tetraphosphate nucleotidehydrolase.

  9. Specific anion effects in Artemia salina.

    PubMed

    Lo Nostro, Pierandrea; Ninham, Barry W; Carretti, Emiliano; Dei, Luigi; Baglioni, Piero

    2015-09-01

    The specific anion effect on the vitality of Artemia salina was investigated by measuring the Lethal Time LT50 of the crustaceans in the presence of different sodium salts solutions at room temperature and at the same ionic strength as natural seawater. Fluoride, thiocyanate and perchlorate are the most toxic agents, while chloride, bromide and sulfate are well tolerated. The rates of oxygen consumption of brine shrimps were recorded in mixed NaCl+NaF or NaCl+NaSCN solutions as a function of time. The results are discussed in terms of the Hofmeister series, and suggest that, besides the biochemical processes that involve F(-), SCN(-) and ClO4(-), the different physico-chemical properties of the strong kosmotropic and chaotropic anions may contribute in determining their strong toxicity for A. salina.

  10. The swimming mechanics of Artemia Salina

    NASA Astrophysics Data System (ADS)

    Ruiz-Angulo, A.; Ramos-Musalem, A. K.; Zenit, R.

    2013-11-01

    An experimental study to analyze the swimming strategy of a small crustacean (Artemia Salina) was conducted. This animal has a series of eleven pairs of paddle-like appendices in its thorax. These legs move in metachronal-wave fashion to achieve locomotion. To quantify the swimming performance, both high speed video recordings of the legs motion and time-resolved PIV measurements of the induced propulsive jet were conducted. Experiments were conducted for both tethered and freely swimming specimens. We found that despite their small size, the propulsion is achieved by an inertial mechanism. An analysis of the efficiency of the leg wave-like motion is presented and discussed. A brief discussion on the mixing capability of the induced flow is also presented.

  11. Toxicity assessment of zero valent iron nanoparticles on Artemia salina.

    PubMed

    Kumar, Deepak; Roy, Rajdeep; Parashar, Abhinav; Raichur, Ashok M; Chandrasekaran, Natarajan; Mukherjee, Anita; Mukherjee, Amitava

    2017-01-19

    The present study deals with the toxicity assessment of two differently synthesized zero valent iron nanoparticles (nZVI, chemical and biological) as well as Fe(2+) ions on Artemia salina at three different initial concentrations of 1, 10, and 100 mg/L of these particles. The assessment was done till 96 h at time intervals of 24 h. EC50 value was calculated to evaluate the 50% mortality of Artemia salina at all exposure time durations. Between chemically and biologically synthesized nZVI nanoparticles, insignificant differences in the level of mortality were demonstrated. At even 24 h, Fe(2+) ion imparted complete lethality at the highest exposure concentration (100 mg/L). To understand intracellular oxidative stress because of zero valent iron nanoparticles, ROS estimation, SOD activity, GSH activity, and catalase activity was performed which demonstrated that ionic form of iron is quite lethal at high concentrations as compared with the same concentration of nZVI exposure. Lower concentrations of nZVI were more toxic as compared with the ionic form and was in order of CS-nZVI > BS-nZVI > Fe(2+) . Cell membrane damage and bio-uptake of nanoparticles were also evaluated for all three concentrations of BS-nZVI, CS-nZVI, and Fe(2+) using adult Artemia salina in marine water; both of which supported the observations made in toxicity assessment. This study can be further explored to exploit Artemia salina as a model organism and a biomarker in an nZVI prone aquatic system to detect toxic levels of these nanoparticles.

  12. Preliminary results of the Artemia salina experiments in biostack on LDEF

    NASA Technical Reports Server (NTRS)

    Graul, E. H.; Ruether, W.; Hiendl, C. O.

    1992-01-01

    The mosaic egg of the brine shrimp, Artemia salina, resting in blastula or gastrula state represents a system that during further development, proceeds without any further development to the larval stage, the free swimming nauplius. Therefore, injury to a single cell of the egg will be manifest in the larvae. In several experiments, it was shown that the passage of a single heavy ion through the shrimp egg damaged a cellular area large enough to disturb either embryogenesis or further development of the larvae, or the integrity of the adult individual. Emergence from the egg shell was heavily disturbed by the heavy ions as was hatching. Additional late effects, due to a hit by a heavy ion, are delayed of growth and of sexual maturity, and reduced fertility. Anomalies in the body and the extremities could be observed more frequently for the nauplii which had developed from eggs hit by heavy ions.

  13. Toxicity of clove essential oil and its ester eugenyl acetate against Artemia salina.

    PubMed

    Cansian, R L; Vanin, A B; Orlando, T; Piazza, S P; Puton, B M S; Cardoso, R I; Gonçalves, I L; Honaiser, T C; Paroul, N; Oliveira, D

    2017-03-01

    The production of compounds via enzymatic esterification has great scientific and technological interest due to the several inconveniences related to acid catalysis, mainly by these systems do not fit to the concept of "green chemistry". Besides, natural products as clove oil present compounds with excellent biological potential. Bioactives compounds are often toxic at high doses. The evaluation of lethality in a less complex animal organism can be used to a monitoring simple and rapid, helping the identification of compounds with potential insecticide activity against larvae of insect vector of diseases. In this sense, the toxicity against Artemia salina of clove essential oil and its derivative eugenyl acetate obtained by enzymatic esterification using Novozym 435 as biocatalyst was evaluated. The conversion of eugenyl acetate synthesis was 95.6%. The results about the evaluation of toxicity against the microcrustacean Artemia salina demonstrated that both oil (LC50= 0.5993 µg.mL-1) and ester (LC50= 0.1178 µg.mL-1) presented high toxic potential, being the eugenyl acetate almost 5 times more toxic than clove essential oil. The results reported here shows the potential of employing clove oil and eugenyl acetate in insecticide formulations.

  14. Toxic Assessment of Triclosan and Triclocarban on Artemia salina.

    PubMed

    Xu, Xiaolu; Lu, Yin; Zhang, Deyong; Wang, Yinyin; Zhou, Xianshan; Xu, Huiying; Mei, Yu

    2015-12-01

    In this study, we investigated the possible acute toxic and genotoxic effects of triclosan (TCS) and triclocarban (TCC) on Artemia salina. Genotoxicity was evaluated using single-cell gel electrophoresis and apoptotic frequency assays (Annexin V-FITC/PI assay). Acute toxicity test results showed that TCC (LC50-24 h = 17.8 µg/L) was more toxic than TCS (LC50-24 h = 171.1 µg/L). Significant increases in both genotoxic biomarkers were observed at 24 h after initial exposure, indicating that these two chemicals are potentially dangerous for this aquatic biological model. Although further studies are required, a comparison of data both in vitro and in vivo allowed us to suggest possible mechanisms of action for TCS and TCC in this sentinel organism.

  15. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    PubMed

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina.

  16. Purification and characterization of a carboxymethyl cellulase from Artemia salina.

    PubMed

    Zin, Hyun Woo; Park, Kwang-Hyun; Choi, Tae Jin

    2014-01-03

    Brine shrimp (Artemia salina) belong to a group of crustaceans that feed on microalgae and require a cellulase enzyme that can be used in ethanol production from marine algae. Protein with potential cellulase activity was purified and the activity analyzed under different conditions. After initial identification of cellulase activity by CMC cellulase, surface sterilization and PCR using 16s rRNA primers was conducted to confirm that the cellulase activity was not produced from contaminating bacteria. The enzyme was purified by ammonium sulfate fractionation, gel filtration, and ion exchange chromatography. After the final purification, a 70-fold increase in specific enzyme activity was observed. SDS-PAGE results revealed that the cellulase enzyme had a molecular mass of 96 kDa. Temperature, pH, and salinity values were found to be optimal at 55 °C, pH 8.0, and 600 mM NaCl, respectively. Specifically, the enzyme showed a fivefold increase in enzyme activity in seawater compared to 600 mM NaCl in phosphate buffer. Further analysis of the purified enzyme by molecular spectrometry showed no match to known cellulases, indicating this enzyme could be a novel halophilic cellulase that can be used for the production of bioethanol from marine macroalgae.

  17. Antennular sensilla of the brine shrimp, Artemia salina.

    PubMed

    Tyson, G E; Sullivan, M L

    1979-06-01

    1. Scanning electron microscopy was used to characterize the external morphology of setae found on the antennules of adults and nauplii of the brine shrimp, Artemia salina (L.). The permeability of the antennular setae was studied by means of Slifer's crystal violet method. 2. Each antennule of an adult brine shrimp possessed a terminal cluster of sensory setae. Within a cluster there were two morphologically distinct kinds of sensilla, here designated type 1 and type 2. Three type 1 sensilla were observed on every antennule examined. The number of type 2 sensilla per antennule was usually four or five. 3. Type 1 sensilla of adults were 43 to 80 micrometer long and simple in external morphology. They were widest at the base, decreased in diameter gradually, and terminated as a finely tapered tip. No pores were resolved by scanning electron microscopy. 4. Type 2 sensilla of adults were shorter (shaft length, 12 to 23 micrometer) and displayed a single pore at the tip (average pore diameter, 0.4 micrometer). In thin section they were seen to possess a distinctive articular specialization of the cuticle at the base of the seta. 5. Dye penetration experiments indicated that type 2 sensilla were permeable to aqueous crystal violet, whereas type 1 sensilla were not. 6. The antennular setae of nauplii resembled type 1 sensilla in general shape, in being impermeable to crystal violet, and in lacking a terminal pore and basal articular specialization. Moreover, a total of three setae was normally present on each naupliar antennule, and the same number of type 1 sensilla was found on each adult antennule examined. If the three naupliar setae represent a developmental stage in the formation of three adult sensilla, available observations suggest that the larval setae are developmentally related to type 1, rather than to type 2 adult sensilla.

  18. On the motility of living invertebrates The case of Artemia Salina

    NASA Astrophysics Data System (ADS)

    Huerta, R.; Hernández, A.; Alvarado-Gil, J. J.

    1998-08-01

    Using a laser beam deflection technique a non-destructive and non-invasive method is developed. This method is applied to monitor the motility of small invertebrates, in particular we study the important case of the crustacean Artemia Salina and the motion of its different parts. We find out that its dynamics can be explained as a superposition of several periodic motions with very well defined frequencies.

  19. Phylogeography and local endemism of the native Mediterranean brine shrimp Artemia salina (Branchiopoda: Anostraca).

    PubMed

    Muñoz, Joaquín; Gómez, Africa; Green, Andy J; Figuerola, Jordi; Amat, Francisco; Rico, Ciro

    2008-07-01

    There has been a recent appreciation of the ecological impacts of zooplanktonic species invasions. The North American brine shrimp Artemia franciscana is one such alien invader in hyper-saline water ecosystems at a global scale. It has been shown to outcompete native Artemia species, leading to their local extinction. We used partial sequences of the mitochondrial Cytochrome c Oxidase Subunit 1 (COI or cox1) gene to investigate the genetic diversity and phylogeography of A. salina, an extreme halophilic sexual brine shrimp, over its known distribution range (Mediterranean Basin and South Africa) and to assess the extent of local endemism, the degree of population structure and the potential impact of traditional human saltpan management on this species. We also examined the phylogenetic relationships in the genus Artemia using COI sequences. Our results show extensive regional endemism and indicate an early Pleistocene expansion of A. salina in the Mediterranean Basin. Subsequent population isolation in a mosaic of Pleistocene refugia is suggested, with two or three refugia located in the Iberian Peninsula. Two instances of long-distance colonization were also observed. Surprisingly, given its strong phylogeographical structure, A. salina showed a signature of correlation between geographical and genetic distance. Owing to strong 'priority effects', extensive population differentiation is retained, despite dispersal via migrant birds and human management of saltpans. The foreseeable expansion of A. franciscana is likely to be followed by substantial loss of genetic diversity in Mediterranean A. salina. Large genetic divergences between Mediterranean and South African A. salina suggest that the latter deserves species status.

  20. Toxicity of benthic dinoflagellates on grazing, behavior and survival of the brine shrimp Artemia salina.

    PubMed

    Neves, Raquel A F; Fernandes, Tainá; Santos, Luciano Neves Dos; Nascimento, Silvia M

    2017-01-01

    Harmful algae may differently affect their primary grazers, causing sub-lethal effects and/or leading to their death. The present study aim to compare the effects of three toxic benthic dinoflagellates on clearance and grazing rates, behavioral changes, and survival of Artemia salina. Feeding assays consisted in 1-h incubations of brine shrimps with the toxic Prorocentrum lima, Gambierdiscus excentricus and Ostreopsis cf. ovata and the non-toxic Tetraselmis sp. Brine shrimps fed unselectively on all toxic and non-toxic algal preys, without significant differences in clearance and ingestion rates. Acute toxicity assays were performed with dinoflagellate cells in two growth phases during 7-h to assess differences in cell toxicity to A. salina. Additionally, exposure to cell-free medium was performed to evaluate its effects on A. salina survival. The behavior of brine shrimps significantly changed during exposure to the toxic dinoflagellates, becoming immobile at the bottom by the end of the trials. Dinoflagellates significantly affected A. salina survival with 100% mortality after 7-h exposure to cells in exponential phase (all treatments) and to P. lima in stationary phase. Mortality rates of brine shrimps exposed to O. cf. ovata and G. excentricus in stationary phase were 91% and 75%, respectively. However, incubations of the brine shrimps with cell-free medium did not affect A. salina survivorship. Significant differences in toxic effects between cell growth phases were only found in the survival rates of A. salina exposed to G. excentricus. Acute exposure to benthic toxic dinoflagellates induced harmful effects on behavior and survival of A. salina. Negative effects related to the toxicity of benthic dinoflagellates are thus expected on their primary grazers making them more vulnerable to predation and vectors of toxins through the marine food webs.

  1. Study of cosmic ray effects on Artemia salina eggs during the Apollo 16 and 17 flights.

    PubMed

    Planel, H; Soleilhavoup, J P; Blanquet, Y; Kaiser, R

    1974-01-01

    We have used Artemia salina eggs, embedded in polyvinyl alcohol, to study the biological effects of heavy ions of cosmic rays. Each biological layer was sandwiched between track detectors. Hit eggs by heavy ions show a great inhibition of their developmental ability. A lower inhibition is observed for eggs that were flown but not hit. Simulation experiments are in progress to determine the factors responsible for inhibition of eggs that were not hit and to improve our knowledge of cellular damage induced by heavy ions.

  2. Dephosphorylation of cytoplasmic non-polysomal messenger ribonucleoproteins from cryptobiotic gastrulae of Artemia salina.

    PubMed

    Van Hove, L; Thoen, C; Cohen, P; Slegers, H

    1985-09-30

    Cytoplasmic non-polysomal mRNP from cryptobiotic gastrulae of the brine shrimp Artemia salina do not contain endogeneous protein phosphatase activity. However, both non-polysomal mRNP and purified mRNP proteins, phosphorylated by mRNP associated protein kinase, can be dephosphorylated by protein phosphatases purified from A. salina cytosol and rabbit skeletal muscle. The 38 kDa and 23.5 kDa poly(A) binding proteins (P38 and P23.5) and a 65 kDa protein are the major substrates of each protein phosphatase used. The reversible phosphorylation-dephosphorylation of mRNP may be involved in the regulation of mRNP metabolism, by altering the poly(A) binding capacities of the mRNP proteins.

  3. A bioassay using Artemia salina for detecting phototoxicity of plant coumarins.

    PubMed

    Ojala, T; Vuorela, P; Kiviranta, J; Vuorela, H; Hiltunen, R

    1999-12-01

    Artemia salina (brine shrimp) has been successfully used for toxicity testing, and a screening test for phototoxicity has been developed based on this method. The ability of the method to test the phototoxic potential of seven known compounds was investigated. Athamantin (an angular furanocoumarin) and umbelliferone (a simple coumarin) showed no phototoxicity, while linear furanocoumarins exhibited phototoxic activity in the following order: psoralen > bergapten > peucedanin > xanthotoxin. The applicability of this method was also tested in screening the phototoxicity of plant material. Six plants from Apiaceae [Aegopodium podagraria L., Anethum graveolens L., Angelica archangelica L., Levisticum officinalis Koch, Petroselinum crispum (P. Mill) A. W. Hill., and Peucedanum palustre (L.) Moench] and one from Rutaceae (Ruta graveolens L.) were selected, all of them known to contain furanocoumarins. Extracts from leaves collected at different times during the growth period were used in the screening. Our results were in accordance with the furanocoumarin content of these plants and with the results of other phototoxicity tests. The Artemia salina method proved to be rapid, simple and inexpensive, and is therefore ideal in the initial biological screening of large numbers of samples for simultaneous detection of both toxicity and phototoxicity.

  4. [Biological and biochemical quality of the Artemia (Anostraca: Artemiidae) population from Real de Salinas saltworks, Calkiní, Campeche, Mexico].

    PubMed

    Rodríguez-Canché, Leticia G; Maldonado-Montiel, Teresita D N J; Carrillo Navarro, Luciano A

    2006-12-01

    Cysts of Artemia spp. collected from February 1997 to February 2000 in the Real de Salinas solar saltworks, Campeche, Mexico, were compared with Artemia franciscana (batch number 8,131 Microfeast Artemia Cysts, Texas, USA). The variables determined in these two populations were: number of cysts per gram, hatching percentage, hatching efficiency, hatching rate, hatching synchrony and hatching biomass, as well as diameter of the cysts and length of the nauplii (instar I). For Salinas, the average diameters of the encapsulated and decapsulated cysts were 230.5 +/- 4.14 and 221.8 +/- 3.39 microm, respectively. The thickness of the cyst shell was 4.35 +/- 0.68 microm and the length of the nauplii was 388.11 +/- 4.39 microm, this last value is among the smallest reported in the literature. For the commercial population of A. franciscana, the average diameters of the encapsulated and decapsulated cysts were 230.21 +/- 12.49 and 216.96 +/- 13.71, respectively. With respect to the corion thickness and length of the nauplii the values were 6.62 +/- 2.72 and 424.70 +/- 30.08, respectively. The protein value of the cysts (47.91 %) and nauplii (50.5 %) of Artemia population from Real de Salinas, are considered adequate to be used as food in aquaculture. The results indicate that the population from Real de Salinas presents positive features for its use in aquaculture in the region.

  5. Accumulation of mercury by Artemia populations of different salinas of Portugal

    SciTech Connect

    Boia, C.M.; Duarte, A.C.

    1995-12-31

    The total mercury content in samples of the brine shrimp Artemia, sediments, water, suspended matter and, when available, algae, from nine salines of Portugal, was evaluated, to find out how mercury present in its natural habitat accumulates in Artemia. This study, carried out between 1990 and 1993, was part of a larger research project aiming to contribute to the knowledge on mercury accumulation and its effects on Artemia. This crustacean is used worldwide for marine species feeding in aquafarms, including in Portugal. The following sampling sites were chosen: some salinas of the lagoon of Aveiro, situated in the northern region of Portugal and partially contaminated with mercury-, the salt-mines of Rio Maior, in the interior of the central region of the country, where there are no sediments (the floor is cemented); and salt-marshes in the Algarve, in the south of Portugal. Mercury was determined by cold vapor absorption espectrofotometry after digestion of samples with sulfuric acid and potassium permanganate, and reference materials have been used to control the analytical performance. The concentrations of total Hg varied from 0.014 to 0.36 mg/Kg in the sediments, 0 to 0.30 {micro}g/g in the Artemia, 0.17 to 0.84 {micro}g/l in the suspended matter and 0.09 to 0.56 {micro}g/l in the water. The content of mercury in the artemias was strongly related to the concentration in the sediments, except when the algae were present, because they also accumulate a significantly percentage of the mercury. No relationships could be established with the Hg in water or in suspended matter (in mass of Hg/volume of filtered water), because their, content in Hg varied a lot with time and weather conditions, such as the wind strength. The presence of Hg in the sediments was due either to significant containing Hg discharges or to the composition of the sediments, being more important in the case of clays.

  6. Artemia salina as test organism for assessment of acute toxicity of leachate water from landfills.

    PubMed

    Svensson, B M; Mathiasson, L; Mårtensson, L; Bergström, S

    2005-03-01

    Artemia salina has, for the first time, been used as test organism for acute toxicity of leachate water from three landfills (the municipal landfills at Kristianstad, Sweden and Siauliai, Lithuania, and an industrial landfill at Stena fragmenting AB, Halmstad, as well as for leachate from Kristianstad treated in different ways in a pilot plan). Artemia can tolerate the high concentrations of chloride ions found in such waters. Large differences in toxicities were found, the leachate from Siauliai being the most toxic one. To increase the selectivity in the measurements, a fractionation was done by using ion exchange to separate ammonium/ammonia and metal ions from the leachate, and activated carbon adsorbents for organic pollutants. The influence of some metals and phenol compounds on the toxicity was investigated separately. It was found that most of the toxicity emanated from the ammonium/ammonia components in the leachate. However, there was also a significant contribution n from organic pollutants, other than phenol compounds, since separate experiments had in this latter case indicated negligible impact. The concentrations of metals were at a level, shown by separate experiments, where only small contribution to the toxicity could be expected.

  7. Biological screening of selected Pacific Northwest forest plants using the brine shrimp (Artemia salina) toxicity bioassay.

    PubMed

    Karchesy, Yvette M; Kelsey, Rick G; Constantine, George; Karchesy, Joseph J

    2016-01-01

    The brine shrimp (Artemia salina) bioassay was used to screen 211 methanol extracts from 128 species of Pacific Northwest plants in search of general cytotoxic activity. Strong toxicity (LC50 < 100 µg/ml) was found for 17 extracts from 13 species, with highest activity observed for Angelica arguta roots at <10 µg/ml. Notably, four species of cedar trees and one of juniper in the family Cupressaceae dominated this group with LC50 for heartwood extracts ranging from 15 to 89 µg/ml. Moderate toxicity (LC50 100-500 µg/ml) was found in 38 extracts from 27 species, while weak toxicity (LC50 500-1000 µg/ml) was detected for 17 extracts in 16 species. There were 139 extracts from 99 species that were non-toxic (LC50 > 1000 µg/ml). Our subsequent studies of conifer heartwoods with strong activity confirm the assay's value for identifying new investigational leads for materials with insecticidal and fungicidal activity.

  8. Tolerance to cadmium and cadmium-binding ligands in Great Salt Lake brine shrimp (Artemia salina)

    SciTech Connect

    Jayasekara, S.; Drown, D.B.; Sharma, R.P.

    1986-02-01

    Information on the accumulation of cadmium in cytosolic proteins of Great Lake brine shrimp (Artemia salina) was obtained from animals collected directly from the lake and also from animal hatched and maintained in three sublethal concentrations of cadmium (0.5, 2.0, 5.0 ppm) in saltwater aquaria. Brine shrimp growth under these conditions was monitored by measuring body lengths during a 7-day exposure period. Heat-stable, cadmium-binding ligands were isolated and identified by Sephadex G-75 chromatography and atomic absorption spectrophotometry. Cadmium was found to be equally distributed between high and low molecular weight proteins in animals collected from the lake and the 0.5 ppm cadmium group. There was also a slight growth stimulation noted in the 0.5-pm group. Higher cadmium incorporation was noted in low molecular weight fractions with increasing cadmium concentration in the exposure media. Low molecular weight fractions were also found to have high uv absorption characteristics at 250 nm and low absorption at 280 nm. Molecular weight of the cadmium-binding ligands was found to be 11,000 as estimated by the gel filtration method. De novo synthesis of this protein was increased as a function of cadmium concentration in the media. However, slow accumulation of cadmium in other protein fractions was also noticed in higher cadmium exposure groups, suggesting the existence of possible tolerance mechanisms in brine shrimp exposed to suspected acute cadmium concentrations.

  9. Experimental exposure of Artemia to hepatopancreatic parvo-like virus and subsequent transmission to post-larvae of Penaeus monodon.

    PubMed

    Sivakumar, V K; Sarathi, M; Venkatesan, C; Sivaraj, A; Hameed, A S Sahul

    2009-11-01

    The different life stages of Artemia franciscana were experimentally exposed to Hepatopancreatic parvo-like virus (HPV), in order to evaluate the possibility of Artemia acting as reservoir or carrier for HPV. All the five developmental stages of Artemia were challenged with HPV both by immersion and oral infection routes. The viral infectivity to Artemia was studied by PCR but not much difference in mortality between control and challenge groups were observed. To confirm the vector status of Artemia for HPV, the HPV exposed Artemia were fed to postlarval forms of Penaeus monodon. Post-larvae of P. monodon were fed with HPV exposed Artemia and could get infected upon feeding on them. Mortality was observed in the post-larvae, which were fed with HPV exposed Artemia, and whereas no mortality was observed in post-larvae fed with Artemia not exposed to HPV and these post-larvae were PCR negative for HPV, as well. Results of this experiment suggest that Artemia might be a possible horizontal transmission pathway for HPV. Further research however is required with histology, immunohistochemistry and transmission electron microcopy to determine whether the Artemia are actually infected with this virus or whether they are simply mechanical carriers. This will enable us to understand better whether Artemia is a carrier of this virus and if so the mechanism involved.

  10. Effect of temperature on post-radiation survival of Artemia salina

    SciTech Connect

    Radchenko, L.A.

    1984-01-01

    The postradiative survival rate was studied in one-day Artemia nauplii ..gamma..-irradiation in doses equal to 2.5; 5; 7.5; 10 Gy at medium temperatures of 15, 22, 25, 27/sup 0/C, respectively. A relationship is established between the irradiation effect (stimulation or inhibition) and temperature of the medium. The analysis of Artemia survival rate for stages of development shows that age contributes to the Artemia survival rate, relative to control, dependences on temperature (direct) and on the irradiation dose (inverse). 2 references, 1 figure, 2 tables.

  11. Effect of artificial regulations of Artemia n-3 HUFA content on growth and survival of black seabream ( Sparus macrocephalus) larvae

    NASA Astrophysics Data System (ADS)

    Liu, Jing-Ke

    1998-06-01

    The requirement for dietary n-3 HUFA (highly unsaturated fatty acid) for growth and survival of black seabream ( Sparus macrocephalus) larvae was tested using Artemia with various levels of n-3 HUFA. Four treatments with Artemia differing in their n-3 HUFA were prepared by feeding them various oil emulsions. The results indicated that dietary n-3 HUFA significantly influences fish n-3 HUFA levels and are necessary for good growth and survival of black seabream larvae. The proper value of n-3 HUFA level and DHA, EPA level in Artemia should be 4.273% and 0.873% (wet weight) for good growth and survival in black seabream larvae respectively.

  12. Use of Probiotic Bacillus spp. in Rotifer (Brachionus plicatilis) and Artemia (Artemia urmiana) Enrichment: Effects on Growth and Survival of Pacific White Shrimp, Litopenaeus vannamei, Larvae.

    PubMed

    Jamali, Hadi; Imani, Ahmad; Abdollahi, Daruosh; Roozbehfar, Reza; Isari, Amin

    2015-06-01

    This study was to evaluate the effect of a preparation of Bacillus probiotic (Bacillus licheniformis and B. subtilis, 1:1) on growth and survival rate of Pacific white shrimp, Litopenaeus vannamei larvae. The larvae were fed on Artemia urmiana nauplii and Brachionus plicatilis enriched with the probiotic preparation at 1 × 10(6) CFU mL(-1) rate. The experimental setup was completely randomized design comprised of six treatments, namely solo Artemia nauplii (A) or rotifer (R), Artemia nauplii and rotifer without any enrichment (A + R), Artemia nauplii enrichment with probiotic bacilli (Bacillus licheniformis and B. subtilis) (A + B), rotifer enrichment with probiotic bacilli (R + B) and enriched Artemia nauplii and rotifer (A + R + B). All treatments were performed in triplicate. Chemical parameters of rearing water viz. pH, salinity and temperature were 7.5-8, 30-31 ppt and 31-32 °C, respectively. Photoperiod was 16L:8D. Shrimp larvae were fed Artemia nauplii and rotifers at 5-20 and 10-40 individuals per shrimp larvae four times a day, respectively. Growth and survival rate of larvae were determined at MII, MIII, PL1, PL4, PL7 and PL10 stages. Larvae in A + R + B treatment showed the highest total length (10.89 ± 0.51 mm), weight (674 ± 73 μg) and survival rate (65% ± 3.5). Lowest total length, weight and survival rate (7.96 ± 0.63 mm, 493 ± 52 μg and 24.5 ± 2.4%, respectively) were recorded in treatment B larvae. We concluded that Bacillus probiotic can improve growth and survival rate of Pacific white shrimp larvae without conceivably undesirable effects.

  13. Comparative study of the assay of Artemia salina L. and the estimate of the medium lethal dose (LD50 value) in mice, to determine oral acute toxicity of plant extracts.

    PubMed

    Logarto Parra, A; Silva Yhebra, R; Guerra Sardiñas, I; Iglesias Buela, L

    2001-09-01

    Artemia salina L. (Artemiidae), the brine shrimp larva, is an invertebrate used in the alternative test to determine toxicity of chemical and natural products. In this study the Medium Lethal Concentrations (LC50 value) of 20 plant extracts, Aloe vera (L.) Burm. F. (Aloeaceae), Artemisia absinthium L. (Asteraceae); Citrus aurantium L. (Rutaceae); Cymbopogon citratus (DC. Ex Nees) Stapf (Poaceae); Datura stramonium L. (Solanaceae); Justicia pectoralis Jacq. (Acanthaceae); Musa x paradisiaca L. (Musaceae); Ocimum basilicum L.; O. gratissimum L.; O. tenuiflorum L. (Lamiaceae); Pimenta dioica (L.) Merr. (Myrtaceae); Piper auritum Kunth (Piperaceae); Plantago major L. (Plantaginaceae); Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Ruta graveolens L. (Rutaceae); Senna alata (L.) Roxb. (Fabaceae); Stachytarpheta jamaicensis (L.) Vahl (Verbenaceae); and Thuja occidentalis L. (Cupressaceae), were determined using Artemia salina L. (Artemiidae), with the objective of relating the results to the LD50 values reported in mice (tested at three concentrations: 10, 100, and 1000 microg/mL, for each extract). We found good correlation between the in vivo and the in vitro tests (r = 0.85 p < 0.05), and this method is a useful tool for predicting oral acute toxicity in plant extracts.

  14. Artemia salina as a new index for assessment of acute cytotoxicity during co-composting of sewage sludge and lignocellulose waste.

    PubMed

    El Fels, Loubna; Hafidi, Mohamed; Ouhdouch, Yedir

    2016-04-01

    Considering the necessity to constantly monitor the safety of use of sewage sludge, we have focused on evaluating the toxicity of raw sludge and sludge treated by co-composting with date palm waste using an in vitro assessment of cytotoxicity based on Artemia salina larvae as a simple new sensitive and reliable routine test. The efficiency of co-composting in decreasing sludge toxicity was evaluated in terms of cytotoxicity abatement reaching 100% by the second month of composting for mixture A (1/3 sludge+2/3 date palm waste) and the third month for mixture B (1/2 sludge+1/2 date palm waste). Cytotoxicity abatement was confirmed by the increase of germination index, which reached over 100% with positive correlation for lettuce (R(2)=0.81 and 0.86) and for turnip (R(2)=0.87 and 0.74) for mixtures A and B respectively. A strong correlation between the proposed cytotoxicity test and the evolution of regulatory physical-chemical approaches was found, (R(2)=0.88 and 0.89) for NH4(+)/NO3(-) and (R(2)=0.80 and 0.88) for C/N respectively for mixture A and B. These findings allow the inexpensive bioassay reported to be used as a highly sensitive test to determine the cytotoxicity and maturity of composts.

  15. Calculation of the radiobiological effects of heavy ions on eggs of Artemia salina flown in the Biostack experiments.

    PubMed

    Heinrich, W

    1977-01-01

    By factorizing fragmentation cross-sections of ions into a projectile and a target-depending part, their flux inside a space vehicle can be calculated. This factorization was found at Bevalac for high-energy oxygen and carbon ions. With some restrictions, an extension of the factorization law to heavier nuclei up to iron is indicated by cosmic-ray data. Using this factorization the known cross-sections for the fragmentation of heavy ions (Z=6-26) in collisions with protons were extrapolated to heavier target nuclei and the energy spectra of nuclei of different charges in the interior of' the Biostack were calculated. The theory of Katz was applied to estimate the heavy-ion-induced radiation damage in Artemia salina. The results are compared with experiment.

  16. The ability of the branchiopod, Artemia salina, to graze upon harmful algal blooms caused by Alexandrium fundyense, Aureococcus anophagefferens, and Cochlodinium polykrikoides

    NASA Astrophysics Data System (ADS)

    Marcoval, M. Alejandra; Pan, Jerónimo; Tang, Yingzhong; Gobler, Christopher J.

    2013-10-01

    We present experiments that examined the grazing and survivorship of zooplankton native (Acartia tonsa) and non-native (Artemia salina) to NY (USA) estuaries when exposed to blooms and cultures of the three harmful algae native to NY, Alexandrium fundyense, Aureococcus anophagefferens (strains CCMP 1850 and CCMP 1984) and Cochlodinium polykrikoides. During experiments with cultures of A. anophagefferens, clearance rates (CR) of A. salina were significantly greater than those of A. tonsa for both algal strains examined. A. salina fed on cultures of C. polykrikoides at higher rates than all phytoplankton species examined, including the control diet (Rhodomonas salina), and faster than rates of A. tonsa fed C. polykrikoides. During experiments with A. fundyense, A. salina actively grazed all cell concentrations (250-1500 cells ml-1) while A. tonsa did not feed at any concentration. Percent mortality of A. salina and A. tonsa fed A. fundyense for 48 h were 43 ± 7.7% and 72 ± 7.8%, respectively, percentages significantly higher than those of individuals fed all other algal diets. During 25 field experiments using natural blooms of the three HAB species performed across six NY estuaries, A. salina significantly (p < 0.05) reduced cell densities of A. anophagefferens, C. polykrikoides, and A. fundyense relative to the control treatments in all but one experiment. The sum of these findings demonstrates that a failure to graze these HABs by the indigenous copepod, A. tonsa, may permit blooms to occur. In addition, the ability of A. salina to graze these HABs at densities that were inhibitory to A. tonsa suggests that A. salina could, in some circumstances, be considered as a part of mitigation strategy for these events.

  17. Topography and stoichiometry of acidic proteins in large ribosomal subunits from Artemia salina as determined by crosslinking

    SciTech Connect

    Uchiumi, T.; Wahba, A.J.; Traut, R.R.

    1987-08-01

    The 60S subunits isolated from Artemia salina ribosomes were treated with the crosslinking reagent 2-iminothiolane under mild conditions. Proteins were extracted and fractions containing crosslinked acidic proteins were obtained by stepwise elution from CM-cellulose. Each fraction was analyzed by diagonal (two-dimensional nonreducing-reducing) NaDodSO/sub 4//polyacrylamide gel electrophoresis. Crosslinked proteins below the diagonal were radioiodinated and identified by two-dimensional acidic urea-NaDodSO/sub 4/ gel electrophoresis. Each of the acidic proteins P1 and P2 was crosslinked individually to the same third protein, PO. The fractions containing acidic proteins were also analyzed by two-dimensional nonequilibrium isoelectric focusing-NaDodSO/sub 4//polyacrylamide gel electrophoresis. Two crosslinked complexes were observed that coincide in isoelectric positions with monomeric P1 and P2, respectively. Both P1 and P2 appear to form crosslinked homodimers. These results suggest the presence in the 60S subunit of (P1)/sub 2/ and (P2)/sub 2/ dimers, each of which is anchored to PO. Protein PO appears to play the same role as L10 in Escherichia coli ribosomes and may form a pentameric complex with the two dimers in the 60S subunits.

  18. Copper(II) complexes with 2-pyridineformamide-derived thiosemicarbazones: Spectral studies and toxicity against Artemia salina

    NASA Astrophysics Data System (ADS)

    Ferraz, Karina O.; Wardell, Solange M. S. V.; Wardell, James L.; Louro, Sonia R. W.; Beraldo, Heloisa

    2009-07-01

    The copper(II) complexes [Cu(H2Am4DH)Cl 2] ( 1), [Cu(H2Am4Me)Cl 2] ( 2), [Cu(H2Am4Et)Cl 2] ( 3) and [Cu(2Am4Ph)Cl] ( 4) with 2-pyridineformamide thiosemicarbazone (H2Am4DH) and its N(4)-methyl (H2Am4Me), N(4)-ethyl (H2Am4Et) and N(4)-phenyl (H2Am4Ph) derivatives were studied by means of infrared and EPR spectral techniques. The crystal structure of 4 was determined. The studied compounds proved to be toxic to Artemia salina, suggesting that they could present cytotoxic activity against solid tumors. Among the free thiosemicarbazones H2Am4Ph presented higher toxicity than all other compounds, which showed comparable effects. In the case of complexes 2 and 3 toxicity is probably attributable to the complex as an entity or to a synergistic effect involving the thiosemicarbazone and copper. H2Am4Ph and complexes 2 and 3 revealed to be the most promising compounds as potential antineoplasic agents.

  19. Chemical investigation of saponins from twelve annual Medicago species and their bioassay with the brine shrimp Artemia salina.

    PubMed

    Tava, Aldo; Pecetti, Luciano

    2012-07-01

    The saponin and sapogenin composition of the aerial growth of 12 annual Medicago species sampled at full senescence were investigated. Saponins were extracted from the plant material and obtained in a highly pure grade by reverse-phase chromatography, with a yield ranging from 0.38 +/- 0.04% to 1.35 +/- 0.08% dry matter, depending on the species. Sapogenins were then obtained after acid hydrolysis of saponins, and evaluated by GC/FID and GC/MS methods. Different compositions of the aglycone moieties were observed in the 12 Medicago species. Medicagenic acid was the dominant aglycone in M. x blancheana, M. doliata, M. littoralis, M. rotata, M. rugosa, M. scutellata, M. tornata and M. truncatula, bayogenin and hederagenin in M. arabica and M. rigidula, echinocystic acid in M. polymorpha, and soyasapogenol B in M. aculeata. The purified saponin mixtures, characterized by different chemical compositions, were then used in a toxicity test using the brine shrimp Artemia salina. The most active compounds were the saponins from M. arabica and M. rigidula with LD50 values of 10.1 and 4.6 microg/mL, respectively. A structure-activity relationship for the tested saponin mixtures was observed.

  20. Comparing cestode infections and their consequences for host fitness in two sexual branchiopods: alien Artemia franciscana and native A. salina from syntopic-populations

    PubMed Central

    Amat, Francisco; Sánchez, Marta I.; Green, Andy J.

    2015-01-01

    The American brine shrimp Artemia franciscana is invasive in the Mediterranean region where it has displaced native species (the sexual A. salina, and the clonal A. parthenogenetica) from many salt pond complexes. Artemia populations are parasitized by numerous avian cestodes whose effects have been studied in native species. We present a study from the Ebro Delta salterns (NE Spain), in a salt pond where both A. franciscana and native A. salina populations coexist, providing a unique opportunity to compare the parasite loads of the two sexual species in syntopy. The native species had consistently higher infection parameters, largely because the dominant cestode in A. salina adults and juveniles (Flamingolepis liguloides) was much rarer in A. franciscana. The most abundant cestodes in the alien species were Eurycestus avoceti (in adults) and Flamingolepis flamingo (in juveniles). The abundance of E. avoceti and F. liguloides was higher in the A. franciscana population syntopic with A. salina than in a population sampled at the same time in another pond where the native brine shrimp was absent, possibly because the native shrimp provides a better reservoir for parasite circulation. Infection by cestodes caused red colouration in adult and juvenile A. salina, and also led to castration in a high proportion of adult females. Both these effects were significantly stronger in the native host than in A. franciscana with the same parasite loads. However, for the first time, significant castration effects (for E. avoceti and F. liguloides) and colour change (for six cestode species) were observed in infected A. franciscana. Avian cestodes are likely to help A. franciscana outcompete native species. At the same time, they are likely to reduce the production of A. franciscana cysts in areas where they are harvested commercially. PMID:26157636

  1. The efficiency of a new hydrodynamic cavitation pilot system on Artemia salina cysts and natural population of copepods and bacteria under controlled mesocosm conditions.

    PubMed

    Cvetković, Martina; Grego, Mateja; Turk, Valentina

    2016-04-15

    A study of the efficiency of hydrodynamic cavitation and separation was carried out to evaluate an innovative, environmentally safe and acceptable system for ballast water treatment for reducing the risk of introducing non-native species worldwide. Mesocosm experiments were performed to assess the morphological changes and viability of zooplankton (copepods), Artemia salina cysts, and the growth potential of marine bacteria after the hydrodynamic cavitation treatment with a different number of cycles. Our preliminary results confirmed the significant efficiency of the treatment since more than 98% of the copepods and A. salina cysts were damaged, in comparison with the initial population. The efficiency increased with the number of the hydrodynamic cavitation cycles, or in combination with a separation technique for cysts. There was also a significant decrease in bacterial abundance and growth rate, compared to the initial number and growth potential.

  2. Ingestion of bacteria overproducing DnaK attenuates Vibrio infection of Artemia franciscana larvae.

    PubMed

    Sung, Yeong Yik; Dhaene, Till; Defoirdt, Tom; Boon, Nico; MacRae, Thomas H; Sorgeloos, Patrick; Bossier, Peter

    2009-11-01

    Feeding of bacterially encapsulated heat shock proteins (Hsps) to invertebrates is a novel way to limit Vibrio infection. As an example, ingestion of Escherichia coli overproducing prokaryotic Hsps significantly improves survival of gnotobiotically cultured Artemia larvae upon challenge with pathogenic Vibrio campbellii. The relationship between Hsp accumulation and enhanced resistance to infection may involve DnaK, the prokaryotic equivalent to Hsp70, a major molecular chaperone in eukaryotic cells. In support of this proposal, heat-stressed bacterial strains LVS 2 (Bacillus sp.), LVS 3 (Aeromonas hydrophila), LVS 8 (Vibrio sp.), GR 8 (Cytophaga sp.), and GR 10 (Roseobacter sp.) were shown in this work to be more effective than nonheated bacteria in protecting gnotobiotic Artemia larvae against V. campbellii challenge. Immunoprobing of Western blots and quantification by enzyme-linked immunosorbent assay revealed that the amount of DnaK in bacteria and their ability to enhance larval resistance to infection by V. campbellii are correlated. Although the function of DnaK is uncertain, it may improve tolerance to V. campbellii via immune stimulation, a possibility of significance from a fundamental perspective and also because it could be applied in aquaculture, a major method of food production.

  3. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae.

    PubMed

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    2016-01-01

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on the impact of nano-sized plastics on marine organisms. Therefore, the present study aims to evaluate the effects of 40nm anionic carboxylated (PS-COOH) and 50nm cationic amino (PS-NH2) polystyrene nanoparticles (PS NPs) on brine shrimp Artemia franciscana larvae. No signs of mortality were observed at 48h of exposure for both PS NPs at naplius stage but several sub-lethal effects were evident. PS-COOH (5-100μg/ml) resulted massively sequestered inside the gut lumen of larvae (48h) probably limiting food intake. Some of them were lately excreted as fecal pellets but not a full release was observed. Likewise, PS-NH2 (5-100µg/ml) accumulated in larvae (48h) but also adsorbed at the surface of sensorial antennules and appendages probably hampering larvae motility. In addition, larvae exposed to PS-NH2 undergo multiple molting events during 48h of exposure compared to controls. The activation of a defense mechanism based on a physiological process able to release toxic cationic NPs (PS-NH2) from the body can be hypothesized. The general observed accumulation of PS NPs within the gut during the 48h of exposure indicates a continuous bioavailability of nano-sized PS for planktonic species as well as a potential transfer along the trophic web. Therefore, nano-sized PS might be able to impair food uptake (feeding), behavior (motility) and physiology (multiple molting) of brine shrimp larvae with consequences not only at organism and population level but on the overall ecosystem based on the key role of zooplankton on marine food webs.

  4. Comparative study on toxicity of ZnO and TiO2 nanoparticles on Artemia salina: effect of pre-UV-A and visible light irradiation.

    PubMed

    Bhuvaneshwari, M; Sagar, Bhawana; Doshi, Siddharth; Chandrasekaran, N; Mukherjee, Amitava

    2017-02-01

    This study evaluated the toxicity potential of ZnO and TiO2 nanoparticles under pre-UV-A irradiation and visible light condition on Artemia salina. The nanoparticle suspension was prepared in seawater medium and exposed under pre-UV-A (0.23 mW/cm(2)) and visible light (0.18 mW/cm(2)) conditions. The aggregation profiles of both nanoparticles (NPs) and dissolution of ZnO NPs under both irradiation conditions at various kinetic intervals (1, 24, 48 h) were studied. The 48-h LC50 values were found to be 27.62 and 71.63 mg/L for ZnO NPs and 117 and 120.9 mg/L for TiO2 NPs under pre-UV-A and visible light conditions. ZnO NPs were found to be more toxic to A. salina as compared to TiO2 NPs. The enhanced toxicity was observed under pre-UV-A-irradiated ZnO NPs, signifying its phototoxicity. Accumulation of ZnO and TiO2 NPs into A. salina depends on the concentration of particles and type irradiations. Elimination of accumulated nanoparticles was also evident under both irradiation conditions. Other than ZnO NPs, the dissolved Zn(2+) also had a significant effect on toxicity and accumulation in A. salina. Increased catalase (CAT) activity in A. salina indicates the generation of oxidative stress due to NP interaction. Thus, this study provides an understanding of the toxicity of photoreactive ZnO and TiO2 NPs as related to the effects of pre-UV-A and visible light irradiation.

  5. Exposure of gnotobiotic Artemia franciscana larvae to abiotic stress promotes heat shock protein 70 synthesis and enhances resistance to pathogenic Vibrio campbellii

    PubMed Central

    Pineda, Carlos; MacRae, Thomas H.; Sorgeloos, Patrick; Bossier, Peter

    2008-01-01

    Larvae of the brine shrimp Artemia franciscana serve as important feed in fish and shellfish larviculture; however, they are subject to bacterial diseases that devastate entire populations and consequently hinder their use in aquaculture. Exposure to abiotic stress was shown previously to shield Artemia larvae against infection by pathogenic Vibrio, with the results suggesting a mechanistic role for heat shock protein 70. In the current report, combined hypothermic/hyperthermic shock followed by recovery at ambient temperature induced Hsp70 synthesis in Artemia larvae. Thermotolerance was also increased as was protection against infection by Vibrio campbellii, the latter indicated by reduced mortality and lower bacterial load in challenge tests. Resistance to Vibrio improved in the face of declining body mass as demonstrated by measurement of ash-free dry weight. Hypothermic stress only and acute osmotic insult did not promote Hsp70 expression and thermotolerance in Artemia larvae nor was resistance to Vibrio challenge augmented. The data support a causal link between Hsp70 accumulation induced by abiotic stress and enhanced resistance to infection by V. campbellii, perhaps via stimulation of the Artemia immune system. This possibility is now under investigation, and the work may reveal fundamental properties of crustacean immunity. Additionally, the findings are important in aquaculture where development of procedures to prevent bacterial infection of feed stock such as Artemia larvae is a priority. PMID:18347942

  6. Evaluation of toxic, cytotoxic, mutagenic, and antimutagenic activities of natural and technical cashew nut shell liquids using the Allium cepa and Artemia salina bioassays.

    PubMed

    Leite, Aracelli de Sousa; Dantas, Alisson Ferreira; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M; Melo-Cavalcante, Ana Amélia de C; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used.

  7. Evaluation of Toxic, Cytotoxic, Mutagenic, and Antimutagenic Activities of Natural and Technical Cashew Nut Shell Liquids Using the Allium cepa and Artemia salina Bioassays

    PubMed Central

    Leite, Aracelli de Sousa; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L.; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M.; Melo-Cavalcante, Ana Amélia de C.; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used. PMID:25861638

  8. Successful Replacement of Artemia salina nauplii with Marine Rotifers (Brachionus plicatilis) in the Diet of Preadult Zebrafish (Danio rerio).

    PubMed

    Lawrence, Christian; James, Althea; Mobley, Scottie

    2015-10-01

    Previously established rearing protocols for zebrafish begin feeding with marine rotifers (Brachionus plicatilis), followed by Artemia nauplii until the fish reach subadult stage, the developmental time point at which they can be most easily transitioned onto a processed diet. However, the inclusion of Artemia is less than ideal, given its fluctuating availability and high costs. We tested whether or not we could replace Artemia with rotifers during our normal rearing sequence and still meet published performance standards for (i) weaning fish onto a processed diet by 25 days postfertilization (dpf) and (ii) successful breeding by 60 dpf. Here, we present the results of trials where wild-type and casper zebrafish were fed exclusively with rotifers (R) or rotifers followed by Artemia (RA) for the first 25 dpf after which point all fish were transitioned to a processed diet (Gemma Micro 300). We measured growth and survival at days 25 and 60, and tested for reproductive capability at 60 dpf. While growth performance was significantly better in the RA groups, we were still able to meet goals for both weaning and generation time in the R groups without compromising survival or sex ratios.

  9. Extractives of seeds of the meliaceae: Effects onSpodoptera frugiperda (J.E. Smith),Acalymma vittatum (F.), andArtemia salina Leach.

    PubMed

    Mikolajczak, K L; Reed, D K

    1987-01-01

    Hexane and ethanol extracts of seeds from 22 species of plants of the family Meliaceae from a number of countries were prepared. The extracts were submitted to antifeedant and toxicity bioassays utilizing fall armyworm [Spodoptera frugiperda (J.E. Smith)] (Lepidoptera: Noctuidae) larvae and striped cucumber beetle [Acalymma vittatum (F.)] (Coleoptera: Chrysomelidae) adults. Toxicity tests were also performed with brine shrimp,Anemia salina Leach. Feeding inhibition and mortality produced by some of these extracts were comparable to and, in certain cases, slightly greater than the effects produced by comparable neem (Azadiracta indica A. Juss.) seed preparations. Brine shrimp toxicity data do not extrapolate to insect activity, and vice versa.

  10. Artemia as a possible vector for Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus transmission (XSV) to Macrobrachium rosenbergii post-larvae.

    PubMed

    Sudhakaran, R; Yoganandhan, K; Ahmed, V P Ishaq; Hameed, A S Sahul

    2006-06-12

    Five developmental stages of Artemia were exposed to Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) by immersion and oral routes in order to investigate the possibility of Artemia acting as a reservoir or carrier of these viruses. The second objective was to determine if virus-exposed Artemia were capable of transmitting the disease to post-larvae (PL) of M. rosenbergii. There was no significant difference in percent mortality between Artemia control groups and groups challenged with these viruses. On the other hand, all the developmental stages of Artemia were positive for both viruses by nested RT-PCR, regardless of the challenge route. In horizontal transmission experiments, 100% mortality was observed in M. rosenbergii PL fed with Artemia nauplii exposed to MrNV and XSV by either challenge route. However, no mortality was observed in PL fed with virus-free Artemia. RT-PCR analysis of the M. rosenbergii PL confirmed the presence of MrNV and XSV in the challenge group and absence in the control group.

  11. Fusaproliferin production by Fusarium subglutinans and its toxicity to Artemia salina, SF-9 insect cells, and IARC/LCL 171 human B lymphocytes.

    PubMed

    Logrieco, A; Moretti, A; Fornelli, F; Fogliano, V; Ritieni, A; Caiaffa, M F; Randazzo, G; Bottalico, A; Macchia, L

    1996-09-01

    Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 micrograms/g of dried ground substrate, with 33 strains producing more than 500 micrograms/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 micrograms/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 microM) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 microM, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 microM in culture in stationary phase after a 48-h exposure). Experiments performed will cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations.

  12. Fusaproliferin production by Fusarium subglutinans and its toxicity to Artemia salina, SF-9 insect cells, and IARC/LCL 171 human B lymphocytes.

    PubMed Central

    Logrieco, A; Moretti, A; Fornelli, F; Fogliano, V; Ritieni, A; Caiaffa, M F; Randazzo, G; Bottalico, A; Macchia, L

    1996-01-01

    Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 micrograms/g of dried ground substrate, with 33 strains producing more than 500 micrograms/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 micrograms/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 microM) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 microM, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 microM in culture in stationary phase after a 48-h exposure). Experiments performed will cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations. PMID:8795229

  13. Determination of TiO2 and AgTiO2 Nanoparticles in Artemia salina: Toxicity, Morphological Changes, Uptake and Depuration.

    PubMed

    Ozkan, Yesim; Altinok, Ilhan; Ilhan, Hasan; Sokmen, Munevver

    2016-01-01

    In this study, aquatic stability and toxic effects of TiO2 and AgTiO2 nanoparticles (NPs) were investigated on Artemia salina nauplii. AgTiO2 was found to be more toxic to nauplii compared to TiO2. The mortality rate in nauplii increased significantly with increasing concentrations and duration of exposure. TiO2 eliminations ranged between 27.8% and 96.5% at 50 and 1 mg/L TiO2 exposed to nauplii, respectively. Accumulation and elimination of Ag in AgTiO2 exposed nauplii were similar except at 1 mg/L AgTiO2. When NPs were mixed with water, the hydrodynamic dimensions of NPs significantly increased because of aggregation in saltwater but NP size decreased over time. NPs-exposed nauplii showed changes in eye formation, enlargement of the intestine, malformations in the outer shell and antennae loss were also observed. Since accumulation and toxicity of AgTiO2 NPs was higher than TiO2 alone, inevitably release of AgTiO2 into aqueous environments can cause ecological risks.

  14. Proteomic analysis of acute responses to copper sulfate stress in larvae of the brine shrimp, Artemia sinica

    NASA Astrophysics Data System (ADS)

    Zhou, Qian; Wu, Changgong; Dong, Bo; Li, Fuhua; Liu, Fengqi; Xiang, Jianhai

    2010-03-01

    Proteomics was used to reveal the differential protein expression profiles of acute responses to copper sulfate exposure in larvae of Artemia sinica. Fourteen differentially displayed protein spots were detected and seven of them were identified. Three spots were up-expressed and identified: actin, heat shock protein 70, and chaperone subunit 1; three down-regulated proteins were identified: arginine kinase, elongation factor-2, and glycine-rich protein; and a newly expressed protein was identified as peroxiredoxin. The study indicates the involvement of all the differentially expressed proteins in the early responses of protein expression, and in the survival of A. sinica in the presence of copper and other heavy metals; the findings improve understanding of the organism’s adaptive responses and resistance.

  15. Poly-ß-hydroxybutyrate content and dose of the bacterial carrier for Artemia enrichment determine the performance of giant freshwater prawn larvae.

    PubMed

    Thai, Truong Quoc; Wille, Mathieu; Garcia-Gonzalez, Linsey; Sorgeloos, Patrick; Bossier, Peter; De Schryver, Peter

    2014-06-01

    The beneficial effects of poly-β-hydroxybutyrate (PHB) for aquaculture animals have been shown in several studies. The strategy of applying PHB contained in a bacterial carrier has, however, hardly been considered. The effect of administering PHB-accumulated Alcaligenes eutrophus H16 containing 10 or 80 % PHB on dry weight, named A10 and A80, respectively, through the live feed Artemia was investigated on the culture performance of larvae of the giant freshwater prawn (Macrobrachium rosenbergii). Feeding larvae with Artemia nauplii enriched in a medium containing 100 and 1,000 mg L(-1) A80 significantly increased the survival with about 15 % and the development of the larvae with a larval stage index of about 1 as compared to feeding non-enriched Artemia. The survival of the larvae also significantly increased with about 35 % in case of a challenge with Vibrio harveyi. The efficiency of these treatments was equal to a control treatment of Artemia enriched in an 800 mg L(-1) PHB powder suspension, while Artemia enriched in 10 mg L(-1) A80, 100 mg L(-1) A10, and 1,000 mg L(-1) A10 did not bring similar effects. From our results, it can be concluded that PHB supplemented in a bacterial carrier (i.e., amorphous PHB) can increase the larviculture efficiency of giant freshwater prawn similar to supplementation of PHB in powdered form (i.e., crystalline PHB). When the level of PHB in the bacterial carrier is high, similar beneficial effects can be achieved as crystalline PHB, but at a lower live food enrichment concentration expressed on PHB basis.

  16. Toxic effects of blooms of marine species of Oscillatoriales on farmed prawns (Penaeus monodon, Penaeus japonicus) and brine shrimp (Artemia salina).

    PubMed

    Smith, P T

    1996-08-01

    Benthic and planktonic blooms of species of Oscillatoriales coincided with mortalities of Penaeus monodon during four episodes at Australian prawn farms. Oscillatoria corakiana was the dominant planktonic species at 65-90,000 cells/ml, but Spirulina sp., Lyngbya sp., Oscillatoria sp. and Nodularia sp. were also identified from the water column, benthic layers or surface mats. The levels and variety of Vibrionaceae in prawn tissue, suggest that mortalities were caused by secondary infections of bacteria. However, experimental results indicate that toxicity of the blooms of Oscillatoriales was the primary cause of disease. Pond water and extracts from a tank culture of benthic Oscillatoriales caused mortalities when injected into P. monodon and P. japonicus. Immersion of artemia in extracts from the tank culture also caused mortalities, with L.D50 values for the supernatant extract of 70 mg/litre for artemia cysts and 50 mg/litre for adult artemia, and LD50 values for the pellet extract of 110 mg/litre for artemia cysts and 200 mg/litre for adult artemia. Experiments with artemia suggested the blooms of Oscillatoriales produced water-soluble, heat-labile toxin/s. Mortalities may have been caused by a neurotoxin because: (a) there was a lack of histopathological evidence of damage to the digestive tracts of prawns during each episode; and (b) artemia cysts immersed in extracts of Oscillatoriales died before they developed digestive tracts. PSP toxin, anatoxin-a, homoanatoxin-a and microcystins were not detected when pond water from a diseased pond was tested. It is proposed that sub-lethal levels of toxin weakened the prawns, causing reduced feeding behaviour and an impaired immune system. As a result, prawns were prone to secondary infection by pathogenic bacteria. Because Oscillatoriales are ubiquitous in prawn farms, the findings have significant implications for the assessment of disease in the prawn farming industry.

  17. Portuguese native Artemia parthenogenetica resisting invasion by Artemia franciscana - Assessing reproductive parameters under different environmental conditions

    NASA Astrophysics Data System (ADS)

    Pinto, Pedro M.; Hontoria, Francisco; Vieira, Natividade; Bio, Ana

    2014-05-01

    There is widespread interest in the conservation of native Artemia biodiversity. In Portugal, only two known populations of native Artemia remain: one in the Rio Maior salina, the other in the Aveiro salina complex, both of the diploid Artemia parthenogenetica species. All other Portuguese hypersaline environments where Artemia can be found have been invaded by Artemia franciscana, which has eradicated the native strains. Invasiveness and resilience of, respectively, exotic and indigenous species are thought to depend on strain-specific traits and adaptation to local conditions. This work evaluates the reproductive performance of the two Portuguese native strains and the invasive species exposed to different salinities, temperatures, photoperiods and food supplies. Reproduction periods, quantity and quality of offspring varied significantly, depending on both the Artemia strain and environmental conditions. A. parthenogenetica from Rio Maior reproduced better than A. franciscana at high salinity (150) and low food supply, which may reflect an adaptation to its biotope that aids its resistance to invasion. But A. parthenogenetica form Aveiro performed much worse than its invasive competitor, under most of the conditions tested. It is unlikely that A. franciscana has not been introduced in this salina by chance alone. Other biological traits of the local A. parthenogenetica or adaptation to unstudied local factors (e.g. pollution) are probably responsible for this strain's survival. Further knowledge on specific local conditions and trait-specific tolerances to biotic and abiotic conditions are needed to understand (non-)invasion patterns and preserve the remaining native populations.

  18. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae

    PubMed Central

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3–1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  19. Bacillus sp. LT3 improves the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged with Vibrio campbellii by enhancing the innate immune response and by decreasing the activity of shrimp-associated vibrios.

    PubMed

    Niu, Yufeng; Defoirdt, Tom; Baruah, Kartik; Van de Wiele, Tom; Dong, Shuanglin; Bossier, Peter

    2014-10-10

    Bacteria belonging to the genus Bacillus are amongst the most intensively studied group of bacteria for use as probiotics in aquaculture. However, the exact mechanism of action of these bacteria is often not well described, and the microbiota that are naturally present in cultures of test organisms often compromise the interpretation of the results. The present study aimed to evaluate the putative probiotic effect of Bacillus sp. LT3 in a model system with gnotobiotic brine shrimp Artemia franciscana larvae. The strain significantly increased the survival of brine shrimp larvae challenged with Vibrio campbellii when administered 6h before the challenge. Under these conditions, LT3 was able to colonize the brine shrimp gastrointestinal tract and to decrease the in vivo pathogen activity as indicated by the bioluminescence of the V. campbellii associated with brine shrimp larvae. In order to investigate the effect of the Bacillus strain on the innate immune system of the brine shrimp larvae, prophenoloxidase and transglutaminase mRNA levels were monitored, while heat shock protein 70 mRNA levels were measured as an indicator of physiological stress. Interestingly, 12h after challenge, the prophenoloxidase mRNA level in the larvae pre-treated with LT3 and challenged with V. campbellii was approximately 8-fold higher than in the other treatments. Further, a decreased mRNA level of transglutaminase gene and heat shock protein 70 gene suggested that pretreatment with LT3 results in less stress and tissue damage in the brine shrimp larvae upon V. campbellii challenge. These results indicated that Bacillus sp. LT3 could improve the survival of brine shrimp larvae when challenged with pathogenic V. campbellii, both by decreasing the in vivo activity of the pathogen and by priming the innate immune response through activating the prophenoloxidase system.

  20. Salinas primer.

    SciTech Connect

    Walsh, Timothy Francis; Reese, Garth M.; Bhardwaj, Manoj Kumar

    2004-08-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis. This capability is required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. General capabilities for modal, statics and transient dynamics are provided. Salinas is similar to commercial codes like Nastran or Abaqus. It has some nonlinear capability, but excels in linear computation. It is different than the above commercial codes in that it is designed to operate efficiently in a massively parallel environment. Even for an experienced analyst, running a new finite element package can be a challenge. This little primer is intended to make part of this task easier by presenting the basic steps in a simple way. The analyst is referred to the theory manual for details of the mathematics behind the work. The User's Notes should be used for more complex inputs, and will have more details about the process (as well as many more examples). More information can be found on our web pages, 3 or 4. Finite element analysis can be deceptive. Any software can give the wrong answers if used improperly, and occasionally even when used properly. Certainly a solid background in structural mechanics is necessary to build an adequate finite element model and interpret the results. This primer should provide a quick start in answering some of the more common questions that come up in using Salinas.

  1. The case of Artemia spp. in nanoecotoxicology.

    PubMed

    Libralato, Giovanni

    2014-10-01

    Artemia spp. is one of the most widespread saltwater organism suitable for ecotoxicity testing, but no internationally standardised methods exist. Several endpoints can be considered with Artemia spp. including short-term (24-48 h) and long-term (14 days) mortality, cysts and nauplii hatchability, biomass productivity, biomarkers' expression/inhibition and bioaccumulation on larvae as well as organisms' reproductive ability. Recently, Artemia spp. started to be used as a reference biological model in nanoecotoxicology with both inorganic and organic engineered nanomaterials (ENMs) also in combination with traditional environmental stressors looking for potential interactive effects. Criticisms were detected about the use of Artemia spp. in relation to the hatching phase, the toxicity test design, the occasional use only of reference toxicants and the way testing solution/suspensions were prepared thus potentially compromising the reliability of nanoecotoxicological results. A full list of compulsory information that must accompany Artemia nanoecotoxicity data is provided with positive feedbacks also for other toxicity bioassays.

  2. Salinas : theory manual.

    SciTech Connect

    Walsh, Timothy Francis; Reese, Garth M.; Bhardwaj, Manoj Kumar

    2011-11-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of structural systems. This manual describes the theory behind many of the constructs in Salinas. For a more detailed description of how to use Salinas, we refer the reader to Salinas, User's Notes. Many of the constructs in Salinas are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Salinas are specific to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programmer notes manual, the user's notes and of course the material in the open literature.

  3. Biomass production and nutritional value of Artemia sp. (Anostraca: Artemiidae) in Campeche, México.

    PubMed

    Maldonado-Montiel, Teresita D N J; Rodríguez-Canché, Leticia G

    2005-01-01

    Biomass of the crustacean Artemia sp. has multiple uses. The biochemical composition and biomass production of Artemia grown from cysts produced by a native population from Real de Salinas were evaluated under laboratory conditions. Nauplii (instar I) were stocked at density of 10 nauplii/ml in 1.5 l tanks, fed with rice bran from day 2 to day 6, and with the microalgae Tetraselmis suecica from day 7 to day 15. At the end of the trial (day 15) the average length was 5.34 mm, biomass production was 15.72 g/l (wet weight), and survival was 79%. The proximal analysis and biochemical composition of Artemia biomass indicated that its nutrient percentages are closely similar to Artemia from other regions, making this species a suitable food for cultured fish and crustacean.

  4. Salinas - User's Notes

    SciTech Connect

    ALVIN,KENNETH F.; BHARDWAJ,MANOJ K.; DRIESSEN,BRIAN; REESE,GARTH M.; SEGALMAN,DANIEL J.

    1999-11-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. This document provides a users guide to the input for Salinas. Details of input specifications for the different solution types, output options, element types and parameters are included. The appendices contain detailed examples, and instructions for running the software on parallel platforms.

  5. Development of transgenic zooplankton Artemia as a bioreactor to produce exogenous protein.

    PubMed

    Chang, Shih-Hung; Lee, Ben-Chang; Chen, Yan-Da; Lee, Yin-Chou; Tsai, Huai-Jen

    2011-10-01

    Although the crustacean Artemia has been commonly used as an experimental organism and served as a live bait feed for aquaculture, gene transfer system on Artemia sp. to generate stable lines is not well developed. In this study, we optimized a condition for cyst-eletroporation and generated stable lines of transgenic A. sinica. Two expression plasmids directed by the hybrid promoters of cytomegalovirus (CMV) and medaka β-actin (Mβ) were co-electroporated on decapsulated cysts: pCMV-Mβ-GFP contained GFP reporter gene and pCMV-Mβ-ypGH contained yellowfin porgy GH (ypGH) cDNA. We examined the GFP shown in the Artemia larvae and found that the expression rate was 13.3% (3,219 out of 24,054 examined). We then chose 200 G0 founders which strongly expressed GFP to generate transgenic lines. Homozygotic strains derived from F4 generation of each transgenic line, A3 and A8, were obtained. We proved that transgenic lines A3 and A8 also harbored pCMV-Mβ-ypGH and produced recombinant ypGH with a concentration of 0.089 and 0.032 μg per 50 homozygotic nauplii, respectively. Ten live Artemia nauplii were fed daily to zebrafish larvae during 25 to 35 days of post-fertilization. The average body length gain rates of zebrafish larvae fed transgenic Artemia were 16-20% greater than those of control group, indicating the exogenous ypGH produced by transgenic Artemia is functional. Therefore, we concluded that the transgenesis on Artemia is developed, and transgenic Artemia might be highly potentially useful as a new bioreactor material for application in aquaculture and biological researches.

  6. High prevalence of cestodes in Artemia spp. throughout the annual cycle: relationship with abundance of avian final hosts.

    PubMed

    Sánchez, Marta I; Nikolov, Pavel N; Georgieva, Darina D; Georgiev, Boyko B; Vasileva, Gergana P; Pankov, Plamen; Paracuellos, Mariano; Lafferty, Kevin D; Green, Andy J

    2013-05-01

    Brine shrimp, Artemia spp., act as intermediate hosts for a range of cestode species that use waterbirds as their final hosts. These parasites can have marked influences on shrimp behavior and fecundity, generating the potential for cascading effects in hypersaline food webs. We present the first comprehensive study of the temporal dynamics of cestode parasites in natural populations of brine shrimp throughout the annual cycle. Over a 12-month period, clonal Artemia parthenogenetica were sampled in the Odiel marshes in Huelva, and the sexual Artemia salina was sampled in the Salinas de Cerrillos in Almería. Throughout the year, 4-45 % of A. parthenogenetica were infected with cestodes (mean species richness = 0.26), compared to 27-72 % of A. salina (mean species richness = 0.64). Ten cestode species were recorded. Male and female A. salina showed similar levels of parasitism. The most prevalent and abundant cestodes were those infecting the most abundant final hosts, especially the Greater Flamingo Phoenicopterus ruber. In particular, the flamingo parasite Flamingolepis liguloides had a prevalence of up to 43 % in A. parthenogenetica and 63.5 % in A. salina in a given month. Although there was strong seasonal variation in prevalence, abundance, and intensity of cestode infections, seasonal changes in bird counts were weak predictors of the dynamics of cestode infections. However, infection levels of Confluaria podicipina in A. parthenogenetica were positively correlated with the number of their black-necked grebe Podiceps nigricollis hosts. Similarly, infection levels of Anomotaenia tringae and Anomotaenia microphallos in A. salina were correlated with the number of shorebird hosts present the month before. Correlated seasonal transmission structured the cestode community, leading to more multiple infections than expected by chance.

  7. High prevalence of cestodes in Artemia spp. throughout the annual cycle: relationship with abundance of avian final hosts

    USGS Publications Warehouse

    Sánchez, Marta I.; Nikolov, Pavel N.; GEorgieva, Darina D.; Georgiev, Boyko B.; Vasileva, Gergana P.; Pankov, Plamen; Paracuellos, Mariano; Lafferty, Kevin D.; Green, Andy J.

    2013-01-01

    Brine shrimp, Artemia spp., act as intermediate hosts for a range of cestode species that use waterbirds as their final hosts. These parasites can have marked influences on shrimp behavior and fecundity, generating the potential for cascading effects in hypersaline food webs. We present the first comprehensive study of the temporal dynamics of cestode parasites in natural populations of brine shrimp throughout the annual cycle. Over a 12-month period, clonal Artemia parthenogenetica were sampled in the Odiel marshes in Huelva, and the sexual Artemia salina was sampled in the Salinas de Cerrillos in Almería. Throughout the year, 4–45 % of A. parthenogenetica were infected with cestodes (mean species richness = 0.26), compared to 27–72 % of A. salina (mean species richness = 0.64). Ten cestode species were recorded. Male and female A. salina showed similar levels of parasitism. The most prevalent and abundant cestodes were those infecting the most abundant final hosts, especially the Greater Flamingo Phoenicopterus ruber. In particular, the flamingo parasite Flamingolepis liguloides had a prevalence of up to 43 % in A. parthenogenetica and 63.5 % in A. salina in a given month. Although there was strong seasonal variation in prevalence, abundance, and intensity of cestode infections, seasonal changes in bird counts were weak predictors of the dynamics of cestode infections. However, infection levels of Confluaria podicipina in A. parthenogenetica were positively correlated with the number of their black-necked grebe Podiceps nigricollis hosts. Similarly, infection levels of Anomotaenia tringae and Anomotaenia microphallos in A. salina were correlated with the number of shorebird hosts present the month before. Correlated seasonal transmission structured the cestode community, leading to more multiple infections than expected by chance.

  8. Molecular cloning and expression analysis of the retinoid X receptor (RXR) gene in golden pompano Trachinotus ovatus fed Artemia nauplii with different enrichments.

    PubMed

    Yang, Qibin; Zheng, Panlong; Ma, Zhenhua; Li, Tao; Jiang, Shigui; Qin, Jian G

    2015-12-01

    The retinoid X receptors (RXRs) are involved in the skeletal development and other biological process such as blood vessel formation and metabolism. Partial sequences of RXRα and β genes were obtained, and their expressions were quantified on golden pompano Trachinotus ovatus at 28 days post hatching (DPH) to explore the molecular response to nutritional manipulation in fish larvae. As live food, Artemia nauplii were separately enriched with Nannochloropsis and Algamac 3080 and non-enriched Artemia nauplii (control) for fish feeding. The expressions of RXRs were detected in the embryos and fish larvae at early stages, suggesting that the skeletal development in golden pompano initiated before yolk re-sorption completion. Fish fed non-enriched Artemia nauplii ended up with higher jaw malformation. The highest specific growth rate was obtained when fish were fed with the Artemia nauplii enriched with Algamac 3080, and the lowest growth rate was observed when fish were fed with unenriched Artemia nauplii. The highest survival was obtained when fish were fed with non-enriched or Nannochloropsis-enriched Artemia nauplii. This study indicates that the use of enriched formula for Artemia nauplii can significantly affect the expression levels of RXRs and jaw malformation of golden pompano larvae, but there is no clear correlation between RXRs expressions and malformation rates when fish are subjected to nutrient challenge.

  9. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight.

    PubMed

    Spooner, B S; DeBell, L; Armbrust, L; Guikema, J A; Metcalf, J; Paulsen, A

    1994-01-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by introduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spaceflight, and show that extensive degrees of development can take place in this microgravity environment.

  10. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight

    NASA Astrophysics Data System (ADS)

    Spooner, B. S.; Debell, L.; Armbrust, L.; Guikema, J. A.; Metcalf, J.; Paulsen, A.

    1994-08-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by intrduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spaceflight, and show that extensive degress of development can take place in this microgravity environment.

  11. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Debell, L.; Armbrust, L.; Guikema, J. A.; Metcalf, J.; Paulsen, A.

    1994-01-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by introduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spa ceflight, and show that extensive degrees of development can take place in this microgravity environment.

  12. Salinas. Theory Manual Version 2.8

    SciTech Connect

    Reese, Garth M.; Walsh, Timothy; Bhardwaj, Manoj K.

    2009-02-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of structural systems. This manual describes the theory behind many of the constructs in Salinas. For a more detailed description of how to use Salinas , we refer the reader to Salinas, Users Notes. Many of the constructs in Salinas are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Salinas are specific to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programmer notes manual, the user's notes and of course the material in the open literature.

  13. Survival and retention of the probiotic properties of Bacillus sp. strains under marine stress starvation conditions and their potential use as a probiotic in Artemia culture.

    PubMed

    Mahdhi, Abdelkarim; Esteban, Maria Ángeles; Hmila, Zeineb; Bekir, Karima; Kamoun, Fathi; Bakhrouf, Amina; Krifi, Boubaker

    2012-12-01

    The probiotic properties of Bacillus strains isolated from Artemia culture and the effect of marine stress on viability and survival were investigated, as well as the changes occurring in their properties. Analyses showed that these bacteria corresponded to the genus Bacillus sp. Antagonism and adherence assays revealed that Bacillus strains have an inhibitory effect against tested pathogenic bacteria and are fairly adherent. Normal and starved cells showed different enzymatic profiles. Challenge tests performed with Artemia larvae provided evidence that the tested Bacillus strains were neither pathogenic nor toxic to the host and conferred protection for Artemia culture against pathogens. The tested strains maintained their viability and their probiotic properties during the period of study. The results suggest that the tested strains have suffered changes allowing them to survive in seawater in the absence of nutrients and outside their natural host, identifying them as potential probiotic candidates for Artemia culture.

  14. Diet affects the redox system in developing Atlantic cod (Gadus morhua) larvae

    PubMed Central

    Penglase, Samuel; Edvardsen, Rolf B.; Furmanek, Tomasz; Rønnestad, Ivar; Karlsen, Ørjan; van der Meeren, Terje; Hamre, Kristin

    2015-01-01

    The growth and development of marine fish larvae fed copepods is superior to those fed rotifers, but the underlying molecular reasons for this are unclear. In the following study we compared the effects of such diets on redox regulation pathways during development of Atlantic cod (Gadus morhua) larvae. Cod larvae were fed a control diet of copepods or the typical rotifer/Artemia diet commonly used in commercial marine fish hatcheries, from first feeding until after metamorphosis. The oxidised and reduced glutathione levels, the redox potential, and the mRNA expression of 100 genes in redox system pathways were then compared between treatments during larval development. We found that rotifer/Artemia-fed cod larvae had lower levels of oxidised glutathione, a more reduced redox potential, and altered expression of approximately half of the redox system genes when compared to copepod-fed larvae. This rotifer/Artemia diet-induced differential regulation of the redox system was greatest during periods of suboptimal growth. Upregulation of the oxidative stress response transcription factor, nrf2, and NRF2 target genes in rotifer/Artemia fed larvae suggest this diet induced an NRF2-mediated oxidative stress response. Overall, the data demonstrate that nutritional intake plays a role in regulating the redox system in developing fish larvae. This may be a factor in dietary-induced differences observed in larval growth. PMID:26099546

  15. Artemia cyst production in Russia

    NASA Astrophysics Data System (ADS)

    Litvinenko, Liudmila I.; Litvinenko, Aleksandr I.; Boiko, Elena G.; Kutsanov, Kirill

    2015-11-01

    In Western Siberia (Russia) there are about 100 Artemia lakes with total area over 1 600 km2. Geographically these lakes are located between 51°-56°N and 61°-82°E. In general these lakes are shallow (depth less than 1.5 m), small or medium size (0.1 to 10 km2); they are chloride; their total salinity is from 40 to 250 g/L. The harvesting of cysts per year is only in 20-40 lakes. In Russia 550 tons of dry Artemia cysts (14%-18% of the world production) were harvested annually. This includes about 350 tons in the Altai region and 200 tons in other regions. During our regular 20-year study period the cyst harvest was: 95 tons in Kurgan; 65 tons in Omsk, 20 tons in Novosibirsk, 20 tons in Tyumen. Ways of increasing cyst harvest in Russia are considered in this article. During the last 30 years the harvest of cysts in Russia has increased from 7-20 to 500-600 tons. A significant influence of dryness of the year was found on productivity in selected lakes, but taken for all the lakes together, the relationship was not significant. The optimal salinity for productivity of cysts in the lakes was determined. Analysis of productivity of the lakes and the harvesting results showed that the stocks of cysts are underutilized by approximately 1.7 times.

  16. Genomic organization and developmental pattern of expression of the engrailed gene from the brine shrimp Artemia.

    PubMed

    Manzanares, M; Marco, R; Garesse, R

    1993-08-01

    We report the isolation and characterization of an engrailed gene in the crustacean Artemia franciscana. The Artemia gene spans a genomic region of 15 kilobases and the coding sequence is interrupted by two introns. It appears to be the only gene of the engrailed family present in the Artemia genome. The predicted engrailed-like protein is 349 amino acids long and contains several domains including the homeodomain, well conserved when compared to other proteins of the engrailed family. Based on sequence comparisons we have detected, in the Artemia engrailed protein, several features which are in common with the Drosophila and Bombyx engrailed proteins. It also has some features specific for invected proteins. Therefore, this gene appears to have diverged from an ancestral gene common to both the engrailed and invected insect genes. Whole-mount in situ hybridization experiments show that the expression of this gene in postembryonic development of Artemia is restricted to the posterior part of at least the thoracic and maxillary segments. The pattern is generated sequentially from a growth zone organized in columns of cells close to the caudal region of the larvae. Cell proliferation in the growth zone follows an interspersed pattern without evidence of early lineage restrictions. The engrailed expression is detected in the growth zone before any segmentation is visible and continues to be expressed in a posterior location in the segments that are morphologically defined. Initially expressed in isolated cells, it spreads into rows broadening to two-three cells as segments mature. The evidence presented here is compatible with the hypothesis that intercellular signaling mechanisms are in part responsible of the early activation of selector genes.

  17. Marine Lactobacillus pentosus H16 protects Artemia franciscana from Vibrio alginolyticus pathogenic effects.

    PubMed

    Garcés, M E; Sequeiros, C; Olivera, N L

    2015-02-10

    Vibrio alginolyticus is an opportunistic pathogen which may affect different aquatic organisms. The aim of this study was to assess the probiotic properties and the protective mode of action of Lactobacillus pentosus H16 against V. alginolyticus 03/8525, through in vitro and in vivo studies using Artemia franciscana (hereafter Artemia). This strain showed antimicrobial activity against V. alginolyticus 03/8525 and Aeromonas salmonicida subsp. salmonicida ATCC33658 possibly related to lactobacilli organic acid production. It was able to survive at high rainbow trout bile concentrations and showed high selective adhesion to rainbow trout mucus (1.2×10(5)±8.0×10(3) cells cm(-2)). H16 outcompeted V. alginolyticus 03/8525 and A. salmonicida subsp. salmonicida ATCC33658, greatly reducing their adherence to rainbow trout mucus (64.8 and 74.1%, respectively). Moreover, H16 produced a cell-bound biosurfactant which caused an important decrease in the surface tension. H16 also protected Artemia nauplii against mortality when it was administered previous to V. alginolyticus 03/8525 inoculation. Furthermore, H16 bioencapsulated in Artemia, suggesting that it is possible to use live carriers in its administration. We conclude that the ability of L. pentosus H16 to selectively adhere to mucosal surfaces and produce cell-bound biosurfactants, displacing pathogenic strains, in addition to its antimicrobial activity, confer H16 competitive advantages against pathogens as demonstrated in in vivo challenge experiments. Thus, L. pentosus H16, a marine bacterium from the intestinal tract of hake, is an interesting probiotic for Artemia culture and also has the potential to prevent vibriosis in other aquaculture activities such as larvae culture and fish farming.

  18. Biological screening of araripe basin medicinal plants using Artemia salina Leach and pathogenic bacteria

    PubMed Central

    da Costa, José Galberto M.; Campos, Adriana R.; Brito, Samara A.; Pereira, Carla Karine B.; Souza, Erlânio O.; Rodrigues, Fabíola Fernandes G.

    2010-01-01

    Background: Many medicinal plant species from the Araripe Basin are widely known and used in folk medicine and for commercial manufacturing of phytotherapeutic products. Few ethnobotanical and pharmacological studies have been undertaken in this region, however, in spite of the great cultural and biological diversity found there. Materials and Methods: Extracts of 11 plant species collected from Ceará state, Brazil, were subjected to the brine shrimp lethality test in order to detect potential sources of novel cytotoxic, antitumor compounds. The larvicidal activity, based on the percentage of larval mortality, was evaluated after 24 h exposure to the treatments. Results: All species tested showed good larvicidal activity as compared to a reference compound and literature data. The extract from Vanillosmopsis arborea was the most active with an LC50 of 3.9 μg/ml. Best results were shown by Lantana montevidensis against Pseudomonas aeruginosa [minimum inhibitory concentration (MIC) 8μg/ml] and Escherichia coli (MIC 32 μg/ml), Zanthoxylum rhoifolium against E. coli (MIC, 256 μg/ml) and Staphylococcus aureus (MIC 64 μg/ml) and Croton zenhtneri against S. aureus (MIC 64 μg/ml). Conclusion: Chemical tests indicated that a wide variety of natural product classes was present in those extracts that showed significant activities in the bioassays. PMID:21120038

  19. Toxicity of some bis Mannich bases and corresponding piperidinols in the brine shrimp (Artemia salina) bioassay.

    PubMed

    Gul, H Inci; Gul, Mustafa; Erciyas, Ercin

    2003-01-01

    Some acetophenone-derived bis Mannich bases were synthesized: bis[beta-benzoylethyl]ethylamine hydrochloride (IIa), bis[beta-(p-methylbenzoyl)ethyl]ethylamine hydrochloride (IIb), bis[beta-(p-chlorobenzoyl)ethyl]ethy- lamine hydrochloride (IId), bis[(2-thienylcarbonyl)ethyl]ethylamine hydrochloride (IIe); some corresponding piperidinol derivatives: 3-benzoyl-1-ethyl-4-phenyl-4-piperidinol hydrochloride (IIIa), 1-ethyl-3-(p-methyl- benzoyl)-4-(p-methylphenyl)-4-piperidinol hydrochloride (IIIb), 1-ethyl-3-(p-methoxybenzoyl)-4-(p-methoxy- phenyl)-4-piperidinol hydrochloride (IIIc), 1-ethyl-3-(p-chlorobenzoyl)-4-(p-chlorophenyl)-4-piperidinol hydrochloride (IIId), 1-ethyl-4-(2-thienyl)-3-(2-thienylcarbonyl)-4-piperidinol hydrochloride (IIIe); and some representative quaternary piperidinols: 3-benzoyl-1-ethyl-4-hydroxy-1-methyl-4-phenylpiperidinium iodide (IIIf), 1-ethyl-4-hydroxy-1-methyl-3-(p-methylbenzoyl)-4-(p-methylphenyl)piperidinium iodide (IIIg). Toxicity was tested by the brine shrimp bioassay as an intermediate test before further in vivo animal experiments. Piperidine derivatives were found to be more potent than bis Mannich bases. Quaternary piperidine derivatives IIIf and IIIg and also non-quaternary piperidine derivatives IIIb, IIIe, IIIc and IIId were more toxic than 5-fluorouracil in brine shrimp bioassay. Except for IIe, bis Mannich bases were not effective. Quaternization and conversion of bis Mannich bases to corresponding piperidines improved the toxicity. The lipid solubility of the compounds may not affect the toxicity. From these findings the quaternary piperidine derivatives IIIf and IIIg could be used in further drug development and also for in vivo experiments.

  20. Organisms for Teaching: "Artemia salina": An Easily Cultured Invertebrate Ideally Suited for Ecological Studies.

    ERIC Educational Resources Information Center

    Ward-Booth, Kirsty; Reiss, Michael

    1988-01-01

    This paper includes a general account of the biology of the brine shrimp, instructions on how the organism may be cultured, the results of some experiments on the ecology and population biology of the species, and some suggestions for further studies. (Author/CW)

  1. Evaluation of toxicity of polluted marine sediments from Bahia Salina Cruz, Mexico.

    PubMed

    Gonzalez-Lozano, Maria Cristina; Mendez-Rodriguez, Lia C; Maeda-Martinez, Alejandro M; Murugan, Gopal; Vazquez-Botello, Alfonso

    2010-01-01

    Bahia Salina Cruz, Oaxaca, Mexico is a major center of oil and refined product distribution on the Mexican Pacific coast. From the start of oil industry operations in 1979, negative effects from discharges of treated effluents in the bay have been a constant concern for local communities. We analyzed 28 surface sediment samples obtained in June, 2002 to evaluate the level of toxicity in the littoral zone, port-harbor, and La Ventosa estuary in Bahia Salina Cruz. The extractable organic matter concentration was high (1,213 to 7,505 micro g g(-1)) in 5 of 7 stations from the port and harbor, whereas it was low in 12 of 16 stations in the littoral zone (36 to 98 micro g g(-1)). The total aromatic hydrocarbon concentration was highest (57 to 142 micro g g(-1)) in the port and harbor compared to the La Ventosa estuary and the littoral zone. Among the heavy metals analyzed, cadmium exceeded the effects range-low values associated with adverse biological effects. The geo-accumulation index of sediments was moderate to strong contamination at 5 stations in the nonlittoral and 6 stations in the littoral zone. The enrichment of lead, zinc, and cadmium at 5 stations from the littoral, port, and harbor suggest that these metals are of anthropogenic origin. Bioassay tests of elutriates of sediments on nauplii of Artemia franciscana and Artemia sp. showed that the port and harbor were more toxic than the La Ventosa estuary and the coastal zone. The Microtox test (Vibrio fischeri) did not show a similar response with the solid phase of the sediments. The results of this study indicate that the high levels of organic content and metals in the sediments of port-harbor and the La Ventosa estuary are mainly caused by anthropogenic activities.

  2. The occurrence of an exotic bisexual Artemia species, Artemia franciscana, in two coastal salterns of Shandong Province, China

    NASA Astrophysics Data System (ADS)

    Zheng, Bo; Sun, Shichun; Ma, Lin

    2004-10-01

    The alien halophilous Artemia species, Artemia franciscana, was found in Chengkou Saltern and Yangkou Saltern of Shandong Province, P.R. China. Although the indigenous parthenogenetic Artemia is detectable, the exotic species is dominant in both salterns. The cross-breeding tests between the exotic A. franciscana and 5 bisexual Artemia species were conducted. The results of hybridization and morphological observations on the exotic A. franciscana are briefly presented in this short communication.

  3. Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle.

    PubMed

    Georgiev, Boyko B; Angelov, Aleksandar; Vasileva, Gergana P; Sánchez, Marta I; Hortas, Francisco; Mutafchiev, Yasen; Pankov, Plamen; Green, Andy J

    2014-09-01

    One of the best examples of rapid displacement of native species by an invader is the eradication of native Artemia salina and A. parthenogenetica in the Mediterranean by the introduced American A. franciscana. Previous studies based on sampling from limited time periods suggest that the success of the American species as a competitor may be due partly to different parasite burden, since native Artemia spp. have high cestode infection rates regulating their density. The aim of this study is to test the hypothesis that the helminth infection in A. franciscana in its invasive range is low throughout its annual life cycle. Samples of A. franciscana were collected every second month from La Tapa saltern (Andalusia) during one year. Five helminth species were recorded: cestodes Flamingolepis liguloides, F. flamingo, Gynandrotaenia stammeri (all flamingo parasites), Eurycestus avoceti (a shorebird parasite) and larval spirurids of the Acuariinae (the first record of nematodes in Artemia). The overall infection rate was low, with total prevalence 5.9% and prevalence of individual parasite species between 0.2 and 3.2%. The mean abundance of helminths was 0.005-0.155 (av. 0.068), 5-13 times lower than in native congeners. Waterbird counts indicate that the low infection rates cannot be explained by lack of definitive hosts. The results are consistent with the hypothesis that helminths have no regulating effect on the invasive brine shrimp in the Mediterranean. The replacement of the native populations by the invader can be partially explained by a competition mediated by parasites/predators through a differential impact on host fitness.

  4. Functional rare males in diploid parthenogenetic Artemia.

    PubMed

    Maccari, M; Gómez, A; Hontoria, F; Amat, F

    2013-09-01

    Functional males that are produced occasionally in some asexual taxa - called 'rare males' - raise considerable evolutionary interest, as they might be involved in the origin of new parthenogenetic lineages. Diploid parthenogenetic Artemia produce rare males, which may retain the ability to mate with females of related sexual lineages. Here, we (i) describe the frequency of male progeny in populations of diploid parthenogenetic Artemia, (ii) characterize rare males morphologically, (iii) assess their reproductive role, using cross-mating experiments with sexual females of related species from Central Asia and characterize the F1 hybrid offspring viability and (iv) confirm genetically both the identity and functionality of rare males using DNA barcoding and microsatellite loci. Our result suggests that these males may have an evolutionary role through genetic exchange with related sexual species and that diploid parthenogenetic Artemia is a good model system to investigate the evolutionary transitions between sexual species and parthenogenetic strains.

  5. Mitochondrial genome sequences of Artemia tibetiana and Artemia urmiana: assessing molecular changes for high plateau adaptation.

    PubMed

    Zhang, Hangxiao; Luo, Qibin; Sun, Jing; Liu, Fei; Wu, Gang; Yu, Jun; Wang, Weiwei

    2013-05-01

    Brine shrimps, Artemia (Crustacea, Anostraca), inhabit hypersaline environments and have a broad geographical distribution from sea level to high plateaus. Artemia therefore possess significant genetic diversity, which gives them their outstanding adaptability. To understand this remarkable plasticity, we sequenced the mitochondrial genomes of two Artemia tibetiana isolates from the Tibetan Plateau in China and one Artemia urmiana isolate from Lake Urmia in Iran and compared them with the genome of a low-altitude Artemia, A. franciscana. We compared the ratio of the rate of nonsynonymous (Ka) and synonymous (Ks) substitutions (Ka/Ks ratio) in the mitochondrial protein-coding gene sequences and found that atp8 had the highest Ka/Ks ratios in comparisons of A. franciscana with either A. tibetiana or A. urmiana and that atp6 had the highest Ka/Ks ratio between A. tibetiana and A. urmiana. Atp6 may have experienced strong selective pressure for high-altitude adaptation because although A. tibetiana and A. urmiana are closely related they live at different altitudes. We identified two extended termination-associated sequences and three conserved sequence blocks in the D-loop region of the mitochondrial genomes. We propose that sequence variations in the D-loop region and in the subunits of the respiratory chain complexes independently or collectively contribute to the adaptation of Artemia to different altitudes.

  6. Nonhatching Decapsulated Artemia Cysts As a Replacement to Artemia Nauplii in Juvenile and Adult Zebrafish Culture.

    PubMed

    Tye, Marc; Rider, Dana; Duffy, Elizabeth A; Seubert, Adam; Lothert, Brogen; Schimmenti, Lisa A

    2015-12-01

    Feeding Artemia nauplii as the main nutrition source for zebrafish is a common practice for many research facilities. Culturing live feed can be time-consuming and requires additional equipment to be purchased, maintained, and cleaned. Nonhatching decapsulated Artemia cysts (decaps) are a commercially available product that can be fed directly to fish. Several other ornamental fish species have been successfully cultured using decaps. Replacing Artemia nauplii with decaps could reduce the overall time and costs associated with the operation of a zebrafish facility. The objective of this study was to determine if decaps could be a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. Wild-type zebrafish were fed one of three dietary treatments: decaps only, nauplii only, or a standard consisting of nauplii plus a commercially prepared pellet food. Survival, growth (length and weight), and embryo production were analyzed between the treatments. Fish receiving the decap diet demonstrated a significantly higher growth and embryo production when compared to the fish receiving the nauplii-only diet. When comparing the decap fish to the standard fish, no significant difference was found in mean survival, mean weight at 90 days postfertilization, or mean embryo production. It was determined that nonhatching decapsulated Artemia cysts can be used as a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture.

  7. Porfirio Salinas and His Bluebonnet Legacy.

    ERIC Educational Resources Information Center

    Coker, Dolores M.

    Porfirio Salinas has been hailed the best painter of the Texas hill country and its bluebonnets. Born on November 6, 1910, Porfirio's teachers recognized and encouraged his drawing ability. When Porfirio found employment after school in a graphics company that also sold art supplies, he met Robert Wood, recognized for his Texas landscapes, and…

  8. Effect of n-3 HUFA levels in rotifers and Artemia on growth and survival of larval black sea bream ( Sparus macrocephalus)

    NASA Astrophysics Data System (ADS)

    Liu, Jingke; Li, Kuiran; Huang, Bingxin; Chen, Xiaolin

    2004-12-01

    Requirement for dietary n-3 HUFA (n-3 highly unsaturated fatty acid) for growth and survival of black sea bream ( Sparus macrocephalus) larvae was studied using rotifers and Artemia at various levels of n-3 HUFA. Five treatments with rotifers and Artemia differing in n-3 HUFA were prepared by enriching them with various oil emulsions. Results indicated that dietary n-3 HUFA significantly influence fish n-3 HUFA levels and are essential for growth and survival of black sea bream larvae. The results also indicated that the incorporation of n-3HUFA TG (triacylglycerols) into tissues of larval black sea bream was more effective from natural fish oil in comparison with n-3 HUFA fatty acid ethyl esters from ethyl-esterified oil.

  9. [Larva migrans].

    PubMed

    Chabasse, D; Le Clec'h, C; de Gentile, L; Verret, J L

    1995-01-01

    Larbish, cutaneous larva migrans or creeping eruption, is a serpiginous cutaneous eruption caused by skin penetration of infective larva from various animal nematodes. Hookworms (Ancylostoma brasiliense, A. caninum) are the most common causative parasites. They live in the intestines of dogs and cats where their ova are deposited in the animal feces. In sandy and shady soil, when temperature and moisture are elevated, the ova hatch and mature into infective larva. Infection occurs when humans have contact with the infected soil. Infective larva penetrate the exposed skin of the body, commonly around the feet, hands and buttocks. In humans, the larva are not able to complete their natural cycle and remain trapped in the upper dermis of the skin. The disease is widespread in tropical or subtropical regions, especially along the coast on sandy beaches. The diagnosis is easy for the patient who is returning from a tropical or subtropical climate and gives a history of beach exposure. The characteristic skin lesion is a fissure or erythematous cord which is displaced a few millimeters each day in a serpiginous track. Scabies, the larva currens syndrome due to Strongyloides stercoralis, must be distinguished from other creeping eruptions and subcutaneous swelling lesions caused by other nematodes or myiasis. Medical treatments are justified because it shortens the duration of the natural evolution of the disease. Topical tiabendazole is safe for localized invasions, but prolonged treatment may be necessary. Oral thiabendazole treatment for three days is effective, but sometimes is associated with adverse effects. Trials using albendazole for one or four consecutive days appear more efficacious. More recent trials using ivermectine showed that a single oral dose can cure 100% of the patients; thus, this drug looks very promising as a new form of therapy. Individual prophylaxis consists of avoiding skin contact with soil which has been contaminated with dog or cat feces

  10. Uptake of metronidazole in Artemia at different developmental life stages.

    PubMed

    Rodriguez, Loretta; Livengood, Elisa J; Miles, Richard D; Chapman, Frank A

    2011-06-01

    The purpose of this study was to examine the capacity of live brine shrimp Artemia spp. to accumulate metronidazole at different developmental life stages. Metronidazole is used in fish as an antiparasitic medication. An effective drug delivery method is to enrich the Artemia with metronidazole and offer them as live feed to the infected fish, usually ornamental species and other small fishes. Artemia cysts were hatched and then soaked in a metronidazole solution (0.05%) at instars 1-3 of larval development. Our findings indicated that Artemia were able to accumulate metronidazole at levels considered therapeutic to other animals and humans (25-100 mg/kg). However, the levels varied depending on the stage of larval development. Artemia accumulated the highest levels of metronidazole (137-143 mg/kg) when they started filter feeding (instar 2), whereas newly hatched Artemia (instar 1) contained the lowest level (85 mg/kg). Based on this study and a review of the literature, a new protocol recommended for enriching Artemia with metronidazole consists of soaking the Artemia in a 0.05% metronidazole solution for 3 h at room temperature. Because metronidazole is relatively insoluble in water, it must first be dissolved in warm water with continuous stirring.

  11. Cryptic microsporidian parasites differentially affect invasive and native Artemia spp.

    PubMed

    Rode, Nicolas O; Lievens, Eva J P; Segard, Adeline; Flaven, Elodie; Jabbour-Zahab, Roula; Lenormand, Thomas

    2013-09-01

    We investigated the host specificity of two cryptic microsporidian species (Anostracospora rigaudi and Enterocytospora artemiae) infecting invasive (Artemia franciscana) and native (Artemia parthenogenetica) hosts in sympatry. Anostracospora rigaudi was on average four times more prevalent in the native host, whereas E. artemiae was three times more prevalent in the invasive host. Infection with An. rigaudi strongly reduced female reproduction in both host species, whereas infection with E. artemiae had weaker effects on female reproduction. We contrasted microsporidian prevalence in native A. franciscana populations (New World) and in both invaded and non-invaded Artemia populations (Old World). At a community level, microsporidian prevalence was twice as high in native compared with invasive hosts, due to the contrasting host-specificity of An. rigaudi and E. artemiae. At a higher biogeographical level, microsporidian prevalence in A. franciscana did not differ between the invaded populations and the native populations used for the introduction. Although E. artemiae was the only species found both in New and Old World populations, no evidence of its co-introduction with the invasive host was found in our experimental and phylogeographic tests. These results suggest that the success of A. franciscana invasion is probably due to a lower susceptibility to virulent microsporidian parasites rather than to decreased microsporidian prevalence compared with A. parthenogenetica or to lower microsporidian virulence in introduced areas.

  12. Comparative study on fatty acid metabolism of early stages of two crustacean species: Artemia sp. metanauplii and Grapsus adscensionis zoeae, as live prey for marine animals.

    PubMed

    Reis, Diana B; Acosta, Nieves G; Almansa, Eduardo; Navarro, Juan C; Tocher, Douglas R; Andrade, José P; Sykes, António V; Rodríguez, Covadonga

    2017-02-01

    The present study compared the lipid composition and in vivo capability of Artemia sp. metanauplii (the main live prey used in aquaculture) and Grapsus adscensionis zoeae (as a wild zooplankton model) to metabolise unsaturated fatty acids. The two species were incubated in vivo with 0.3μM of individual [1-(14)C]fatty acids (FA) including 18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6 (ARA), 20:5n-3 (EPA) and 22:6n-3 (DHA) bound to bovine serum albumin (BSA). Compared to metanauplii, zoeae contained twice the content of polar lipids (PL) and eight-fold the content of long-chain polyunsaturated fatty acids (LC-PUFA). Artemia sp. metanauplii showed increased short chain fatty acid de novo synthesis from beta-oxidation of [1-(14)C]LC-PUFA, preferentially DHA. Of the LC-PUFA, DHA showed the highest esterification rate into Artemia sp. triacylglycerols. In contrast, in Grapsus zoeae [1-(14)C]DHA displayed the highest transformation rate into longer chain-length FAs and was preferentially esterified into PL. EPA and ARA, tended to be more easily incorporated and/or retained than DHA in Artemia sp. Moreover, both EPA and ARA were preferentially esterified into Artemia PL, which theoretically would favour their bioavailability to the larvae. In addition to the inherent better nutritional value of Grapsus zoeae due to their intrinsic lipid composition, the changes taking place after the lipid incorporation, point at two distinct models of lipid metabolism that indicate zoeae as a more suitable prey than Artemia sp. for the feeding of marine animals.

  13. The effects of different routes of inulin administration on gut microbiota and survival rate of Indian white shrimp post-larvae (Fenneropenaeus indicus)

    PubMed Central

    Hoseinifar, Seyed Hossein; Zare, Parviz; Kolangi Miandare, Hamed

    2015-01-01

    The present study investigates the effects of different routes of inulin administration as prebiotic on gut microbiota and survival rate of Indian white shrimp post-larvae. Four hundred and fifty Indian white shrimp post-larvae (PL1) were stocked in nine tanks. The tanks were assigned into three treatments: feeding with inulin-treated (110 mg L-1) Artemia nauplii (I-T), feeding with inulin-enriched (110 mg L-1) Artemia nauplii (I-E) and control which repeated triplicates. Feeding trial was performed until PL11 stage and then gut microbiota was studied using culture based method. Also, survival rate was calculated at the end of feeding trial. Our results showed that feeding on inulin enriched or treated Artemia nauplii had no significant effect on total viable culturable autochthonous bacteria and Vibrio spp. levels of the gut microbiota (p > 0.05). However, a remarkable increase of lactic acid bacteria levels (LAB) was observed in I-E treatment (p < 0.05). Administration of inulin enriched Artemia nauplii significantly elevated survival rates of Indian white shrimp post-larvae (p < 0.05). These results encourage administration of prebiotic-enriched Artemia nauplii in post larval stage of Indian white shrimp but determination the mode of action of prebiotic on various aspects of shrimp larviculture merit further research. PMID:26973770

  14. The effects of different routes of inulin administration on gut microbiota and survival rate of Indian white shrimp post-larvae (Fenneropenaeus indicus).

    PubMed

    Hoseinifar, Seyed Hossein; Zare, Parviz; Kolangi Miandare, Hamed

    2015-01-01

    The present study investigates the effects of different routes of inulin administration as prebiotic on gut microbiota and survival rate of Indian white shrimp post-larvae. Four hundred and fifty Indian white shrimp post-larvae (PL1) were stocked in nine tanks. The tanks were assigned into three treatments: feeding with inulin-treated (110 mg L(-1)) Artemia nauplii (I-T), feeding with inulin-enriched (110 mg L(-1)) Artemia nauplii (I-E) and control which repeated triplicates. Feeding trial was performed until PL11 stage and then gut microbiota was studied using culture based method. Also, survival rate was calculated at the end of feeding trial. Our results showed that feeding on inulin enriched or treated Artemia nauplii had no significant effect on total viable culturable autochthonous bacteria and Vibrio spp. levels of the gut microbiota (p > 0.05). However, a remarkable increase of lactic acid bacteria levels (LAB) was observed in I-E treatment (p < 0.05). Administration of inulin enriched Artemia nauplii significantly elevated survival rates of Indian white shrimp post-larvae (p < 0.05). These results encourage administration of prebiotic-enriched Artemia nauplii in post larval stage of Indian white shrimp but determination the mode of action of prebiotic on various aspects of shrimp larviculture merit further research.

  15. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae - can we identify the underlying factors?

    PubMed

    Karlsen, Ørjan; van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks.

  16. Groundwater recharge on east side soils of the Salinas Valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    After four years of drought, groundwater levels in the Salinas Valley are at historically low levels which threaten to adversely affect farming in the Salinas Valley. Given the prospect of a strong El Niño this coming winter, it seems prudent to plan to capture as much of the rainfall as possible to...

  17. 21. CHAINAGE FROM SALINAS DAM TO NORTH PORTAL, STATIONS. Leeds, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. CHAINAGE FROM SALINAS DAM TO NORTH PORTAL, STATIONS. Leeds, Hill, Barnard & Jewett drawing, no date, no number, title block partially obscured. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  18. 19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, IN CENTRAL PORTION OF SAN LUIS OBISPO, CALIFORNIA. Leeds Hill Barnard & Jewett - Consulting Engineers, February 1942. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  19. Effects of calanoid copepod Schmackeria poplesia as a live food on the growth, survival and fatty acid composition of larvae and juveniles of Japanese flounder, Paralichthys olivaceus

    NASA Astrophysics Data System (ADS)

    Liu, Guangxing; Xu, Donghui

    2009-12-01

    Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods ( P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated. The results showed that the larvae and juveniles fed with copepods ( S. poplesia) had significantly higher growth rate than those fed with the other two organisms ( P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others ( P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia ( P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its effects on the survival, growth and nutrition composition of the fish.

  20. Experimental vertical transmission of Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) from brooders to progeny in Macrobrachium rosenbergii and Artemia.

    PubMed

    Sudhakaran, R; Ishaq Ahmed, V P; Haribabu, P; Mukherjee, S C; Sri Widada, J; Bonami, J R; Sahul Hameed, A S

    2007-01-01

    White tail disease (WTD) is a serious problem in hatcheries and nursery ponds of Macrobrachium rosenbergii in India. Experiments were carried out to determine the possibility of vertical transmission of M. rosenbergii nodavirus (MrNV) and extra small virus (XSV) in M. rosenbergii and Artemia. Prawn broodstock inoculated with MrNV and XSV by oral or immersion challenge survived without any clinical signs of WTD. The brooders spawned 5-7 days after inoculation and the eggs hatched. The survival rate of larvae gradually decreased, and 100% mortality was observed at the post-larvae (PL) stage. Whitish muscle, the typical sign of WTD, was seen in advanced larval developmental stages. The ovarian tissue and fertilized eggs were found to be positive for MrNV/XSV by reverse transcriptase-polymerase chain reaction (RT-PCR) whereas the larval stages showed positive by RT nested PCR (nRT-PCR). In Artemia, reproductive cysts and nauplii derived from challenged brooders were normal and survival rates were within the expected range for normal rearing conditions. The reproductive cysts were found to be positive for MrNV/XSV by RT-PCR whereas the nauplii showed MrNV/XSV-positive by nRT-PCR. The PL of M. rosenbergii fed nauplii derived from challenged Artemia brooders died at 9 days post-inoculum with clinical signs of WTD.

  1. Embryonic diapause in two species of brine shrimp: Artemia monica and Artemia franciscana

    SciTech Connect

    Drinkwater, L.E.

    1986-01-01

    The brine shrimp, Artemia, has the capacity to produce encysted embryos which are resistant to severe environmental conditions. Upon release from the ovisac, these embryos, or cysts, do not hatch, but remain in a state of developmental arrest imposed by some unknown endogenous mechanism. However, once the proper abiotic signal is received, the embryo is free to resume development. Regulation of this embryonic diapause in two related species of brine shrimp, Artemia franciscana and Artemia monica, is studied. The abiotic cues which terminate diapause and the possibility of a regulatory mechanism involving depressed intracellular pH (pH/sub i/) are investigated. /sup 31/P-NMR studies show that pH/sub i/ of diapause cysts of both species is alkaline, greater than or equal to 7.9, essentially the same as that of activated cysts. A franciscana, which inhabits an unpredictable environment, is activated by several cues: low temperature, dehydration, and elevated levels of CO/sub 2/. A. monica, found in a fairly stable body of water with regular seasonal changes in temperature, breaks diapause only upon exposure to low temperature. Induction of anoxybiosis in diapause and activated cysts is studied using /sup 31/P-NMR to reveal that diapause cysts acidify rapidly in response to anoxia; pH/sub i/ falls to about 7.2 in 30 minutes, much like activated cysts, indicating the presence of a fairly active metabolism. The effects of salinity on cyst activation, hatching, water content, and carbohydrate metabolism are examined.

  2. Strong environmental tolerance of Artemia under very high pressure

    NASA Astrophysics Data System (ADS)

    Minami, K.; Ono, F.; Mori, Y.; Takarabe, K.; Saigusa, M.; Matsushima, Y.; Saini, N. L.; Yamashita, M.

    2010-03-01

    It was shown by the present authors group that a tardigrade in its tun-state can survive after exposed to 7.5 GPa for 13 hours. We have extended this experiment to other tiny animals searching for lives under extreme conditions of high hydrostatic pressure. Artemia, a kind of planktons, in its dried egg-state have strong environmental tolerance. Dozens of Artemia eggs were sealed in a small Teflon capsule together with a liquid pressure medium, and exposed to the high hydrostatic pressure of 7.5 GPa. After the pressure was released, they were soaked in seawater to observe hatching rate. It was proved that 80-90% of the Artemia eggs were alive and hatched into Nauplii after exposed to the maximum pressure of 7.5 GPa for up to 48 hours. Comparing with Tardigrades, Artemia are four-times stronger against high pressure.

  3. Toxicity effect of silver nanoparticles in brine shrimp Artemia.

    PubMed

    Arulvasu, Chinnasamy; Jennifer, Samou Michael; Prabhu, Durai; Chandhirasekar, Devakumar

    2014-01-01

    The present study revealed the toxic effect of silver nanoparticles (AgNPs) in Artemia nauplii and evaluated the mortality rate, hatching percentage, and genotoxic effect in Artemia nauplii/cysts. The AgNPs were commercially purchased and characterized using field emission scanning electron microscope with energy dispersive X-ray spectroscopy. Nanoparticles were spherical in nature and with size range of 30-40 nm. Artemia cysts were collected from salt pan, processed, and hatched in sea water. Artemia nauplii (II instar) were treated using silver nanoparticles of various nanomolar concentrations and LC50 value (10 nM) and mortality rate (24 and 48 hours) was evaluated. Hatching percentage of decapsulated cysts treated with AgNPs was examined. Aggregation of AgNPs in the gut region of nauplii was studied using phase contrast microscope and apoptotic cells in nauplii stained with acridine orange were observed using fluorescence microscope. DNA damage of single cell of nauplii was determined by comet assay. This study showed that as the concentration of AgNPs increased, the mortality rate, aggregation in gut region, apoptotic cells, and DNA damage increased in nauplii, whereas the percentage of hatching in Artemia cysts decreased. Thus this study revealed that the nanomolar concentrations of AgNPs have toxic effect on both Artemia nauplii and cysts.

  4. Dietary neutral lipid level and source in Senegalese sole (Solea senegalensis) larvae: effect on growth, lipid metabolism and digestive capacity.

    PubMed

    Morais, S; Caballero, M J; Conceição, L E C; Izquierdo, M S; Dinis, M T

    2006-05-01

    Contrary to larval essential fatty acid (EFA) requirements, the effect of dietary neutral lipid supply has been little investigated in marine fish larvae. The present work investigates the effect of feeding Senegalese sole larvae on Artemia enriched with higher or lower doses of lipid emulsion. Two lipid sources - soybean oil and fish oil - were compared. From 16 days after hatching (DAH) onwards, larvae were fed one of four experimental treatments: Artemia enriched on a high or low dose of soybean oil emulsion (HS and LS) or Artemia enriched on a high or low dose of fish oil emulsion (HF and LF). In terms of growth, the dietary lipid level did not have a significant effect while the soybean oil treatments induced a lower growth than the fish oil-enriched Artemia. The fatty acid (FA) composition of the larvae closely reflected the dietary quantitative and qualitative FA profile. Only slight dietary effects were noted in the activity of trypsin, lipase and alkaline phosphatase. A higher amount of lipid droplets was noticeable in the posterior intestine epithelia and in the hepatocytes of larvae fed Artemia enriched with higher lipid doses, while LS-Artemia induced the lower lipid accumulation on the basal zone of the enterocytes, in accordance with the lowest total lipid level measured in this treatment. These results suggest an important effect of dietary total lipid level on lipid accumulation in the enterocytes and on FA absorption. At 33 DAH a tube feeding trial was conducted with 14C-labelled oleic acid (OA) or triolein (TRI), showing that the lower accumulation of lipid droplets in the larvae fed LS was associated with a significantly higher absorption and retention in the gut and body tissues of the TRI label. For OA no significant differences between treatments were found. TRI label was considerably more evacuated than OA, indicating that sole larvae may have a lower capacity to incorporate a triacylglycerol, which needs to be digested. Finally, OA appears

  5. New approaches for Artemia pond culture.

    PubMed

    Van Hoa, Nguyen; Le Tran, Huu; Hong Van, Nguyen Thi; Sorgeloos, P; Van Stappen, G

    2013-01-01

    A project for intensive culture of Artemia in Vinhchau solar saltwork was funded by Soctrang Authority. The aim of this project is to increase the average cyst yield of 50kg.ha-1.crop, and to build up a stable culture technique with a better yield for local farmers. Multiple laboratory experiments were set up with inert food including fermented rice bran, tiger shrimp feed (PL15), as well as their combination with live algae (Chaetoceros). Results showed that, under laboratory conditions, fermented rice bran and tiger shrimp feed can be used as supplemental food sources. The shrimp feed alone or in combination with algae always gave better cyst production compared to the others, but should not account for more than 50% of the diet. In the field trials, aeration of Artemia ponds also increased cyst yields (from 195.8+/-44.2 to 207+/-46.1kg.ha-1.crop with 6 and 12 aeration a day, respectively) compared to ponds with no aeration (88.2+/-27.5kg.ha-1.crop), however the returns on investment (ROI=2.73-2.71 with aera tion vs. 2.24 without) are not significantly different. Utilization of fermented rice bran (20kg.ha-1.day) and shrimp feed (6kg.ha-1.day) as a supplementary feed during pond production in combination with greenwater supplies (10% of pond volume daily) resulted in higher yields (96.0+/-15.9 and 157.2+/-15.0kg.ha-1.crop, respectively) than traditional culture; Shrimp feed as a supplemental feed supported the cyst yield but their negative effect was at a high cost vs. traditional culture and use of fermented rice bran. Based on the cyst yield and ROI, fermented rice bran should be a promising item for poor farmers.

  6. Water-quality investigation, Salinas River, California

    USGS Publications Warehouse

    Irwin, G.A.

    1976-01-01

    Concentrations of dissolved solids in the Salinas River, California, are variable and range from 164 to 494 milligrams per liter near Bradley and from 170 to 1,090 milligrams per liter near Spreckels. Higher concentrations near Spreckels are caused mainly by sewage inflow about 150 feet (50 meters) upstream. Concentrations of nitrogen, phosphorus, total organic carbon, selected trace elements, and pesticides also generally increase downstream from Pozo to Spreckels and are related to sewage effluent; however, high concentrations occur elsewhere in the river. Specific conductance and water discharge regression results indicate that relations were all significant at the 1-percent probability level at Paso Robles, Bradley, and Spreckels with the explained variance ranging from 66 to 74 percent. Concentations of nitrogen, phosphorus, total organic carbon, and trace elements are only infrequently related to water discharge. (Woodard-USGS)

  7. Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule.

    PubMed

    Borhani, Heshmat Akbari; Berghmans, Herald; Trashin, Stanislav; De Wael, Karolien; Fago, Angela; Moens, Luc; Habibi-Rezaei, Mehran; Dewilde, Sylvia

    2015-10-01

    In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichia coli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of -0.13V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding.

  8. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae — can we identify the underlying factors?

    PubMed Central

    van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F.; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks. PMID:26038712

  9. Artemia biodiversity in Asia with the focus on the phylogeography of the introduced American species Artemia franciscana Kellogg, 1906.

    PubMed

    Eimanifar, Amin; Van Stappen, Gilbert; Marden, Brad; Wink, Michael

    2014-10-01

    Asia harbors a diverse group of sexual and asexual Artemia species, including the invasive Artemia franciscana, which is native to the Americas. The phylogeny of Asian Artemia species and the phylogeography of the introduced A. franciscana from 81 sampling localities in Eurasia, Africa and America were elucidated using mitochondrial (COI) and nuclear DNA (ITS1) sequences. According to a COI phylogeny, 6 distinctive genetic groups were recognized, with a complex phylogeographic structure among Asian Artemia. A haplotype complex which includes parthenogenetic lineages is distributed in 39 inland geographical localities in Asia, illustrating a wide distribution with a narrow genetic structure on this continent. The invasive A. franciscana was discovered in 31 geographical localities along the southern and eastern coastal regions of Asia. Three sexual species (A. sinica, A. tibetiana and A. urmiana) have a restricted distribution in certain geographical localities in Asia. In contrast to COI phylogeny reconstruction, ITS1 sequences showed inconsistency with the COI tree, indicating incomplete lineage sorting which provided the low genetic divergence in the Asian clade. Asian A. franciscana showed higher haplotype diversity as compared to the source population from the Great Salt Lake (USA), which could be attributed to multiple introductions by mass dispersal in Asia via human activities. The invasive success of A. franciscana in Asia could lead to a long-term biodiversity disturbance of the autochthonous Artemia species on the continent.

  10. Probiont niche specialization contributes to additive protection against Vibrio owensii in spiny lobster larvae.

    PubMed

    Goulden, Evan F; Hall, Michael R; Pereg, Lily L; Baillie, Brett K; Høj, Lone

    2013-02-01

    The development of efficient probiotic application protocols for use in marine larviculture relies on comprehensive understanding of pathogen-probiont-host interactions. The probiont combination of Pseudoalteromonas sp. PP107 and Vibrio sp. PP05 provides additive protection against vectored Vibrio owensii DY05 infection in larvae (phyllosomas) of ornate spiny lobster, Panulirus ornatus. Here, fluorescently tagged strains were used to demonstrate niche specialization of these probionts in both the live feed vector organism Artemia and in phyllosomas. The pathogen was vulnerable to direct interaction with PP05 in the bacterioplankton as well as in the Artemia gut and the phyllosoma foregut and midgut gland. In contrast, PP107 was localized on external surfaces of Artemia and phyllosomas, and direct interaction with the pathogen was limited to the bacterioplankton. While PP107 was the overall dominant ectobiont on the phyllosoma cephalothorax and inner leg segments, PP05 was the primary colonizer of outer leg segments, nutrient-rich locales that may promote ingestion during feeding. This study shows that niche specialization can contribute to the additive probiotic effect of a probiotic mixture and highlights that probiotic enrichment of Artemia cultures can intercept the infection cycle of V. owensii DY05 in early-stage P. ornatus phyllosomas.

  11. A 49 kDa microtubule cross-linking protein from Artemia franciscana is a coenzyme A-transferase.

    PubMed

    Oulton, Mindy M; Amons, Reinout; Liang, Ping; MacRae, Thomas H

    2003-12-01

    Embryos and larvae of the brine shrimp, Artemia franciscana, were shown previously to possess a protein, now termed p49, which cross-links microtubules in vitro. Molecular characteristics of p49 were described, but the protein's identity and its role in the cell were not determined. Degenerate oligonucleotide primers designed on the basis of peptide sequence obtained by Edman degradation during this study were used to generate p49 cDNAs by RT-PCR and these were cloned and sequenced. Comparison with archived sequences revealed that the deduced amino acid sequence of p49 resembled the Drosophila gene product CG7920, as well as related proteins encoded in the genomes of Anopheles and Caenorhabditis. Similar proteins exist in several bacteria but no evident homologues were found in vertebrates and plants, and only very distant homologues resided in yeast. When evolutionary relationships were compared, p49 and the homologues from Drosophila, Anopheles and Caenorhabditis formed a distinct subcluster within phylogenetic trees. Additionally, the predicted secondary structures of p49, 4-hydroxybutyrate CoA-transferase from Clostridium aminobutyricum and glutaconate CoA-transferase from Acidaminococcus fermentans were similar and the enzymes may possess related catalytic mechanisms. The purified Artemia protein exhibited 4-hydroxybutyrate CoA-transferase activity, thereby establishing p49 as the first crustacean CoA-transferase to be characterized. Probing of Western blots with an antibody against p49 revealed a cross-reactive protein in Drosophila that associated with microtubules, but to a lesser extent than did p49 from Artemia.

  12. Impact of brine acidification on hatchability, survival and reproduction of Artemia parthenogenetica and Artemia franciscana in salt ponds, Bohai Bay, China

    NASA Astrophysics Data System (ADS)

    Sui, Liying; Deng, Yuangao; Wang, Jing; Sorgeloos, Patrick; Van Stappen, Gilbert

    2014-01-01

    We studied the effect of pH (pH 5, 6, 7 and 8) on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay (BHB), Artemia franciscana from San Francisco Bay, and A. franciscana artificially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were significantly reduced when exposed to a culture medium at pH 5 for 18 d ( P<0.05). The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order: juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6-8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidification has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franciscana should be feasible at pH 7-8.

  13. Efficiency of Artemia cysts removal as a model invasive spore using a continuous microwave system with heat recovery.

    PubMed

    Balasubramanian, Sundar; Ortego, Jeffrey; Rusch, Kelly A; Boldor, Dorin

    2008-12-15

    A continuous microwave system to treat ballast water inoculated with Artemia salina cysts as a model invasive spore was tested for its efficacy in inactivating the cysts present. The system was tested at two different flow rates (1 and 2 L x min(-1)) and two different power levels (2.5 and 4.5 kW). Temperature profiles indicate that the system could deliver heating loads in excess of 100 degrees C in a uniform and near-instantaneous manner when using a heat recovery system. Except for a power and flow rate combination of 2.5 kW and 2 L x min(-1), complete inactivation of the cysts was observed at all combinations at holding times below 100 s. The microwave treatment was better or equal to the control treatment in inactivating the cysts. Use of heat exchangers increased the power conversion efficiency and the overall efficiency of the treatment system. Cost economics analysis indicates that in the present form of development microwave treatment costs are higher than the existing ballast water treatment methods. Overall, tests results indicated that microwave treatment of ballast water is a promising method that can be used in conjunction with other methods to form an efficient treatment system that can prevent introduction of potentially invasive spore forming species in non-native waters.

  14. Development of a bacterial challenge test for gnotobiotic Nile tilapia Oreochromis niloticus larvae.

    PubMed

    Situmorang, Magdalena Lenny; Dierckens, Kristof; Mlingi, Frank Thomas; Van Delsen, Bart; Bossier, Peter

    2014-04-23

    Gastrointestinal microbiota have an important impact on fish health and disease, stimulating interest in a better understanding of how these gastrointestinal microbial communities are composed and consequently affect host fitness. In this respect, probiotic microorganisms have been extensively used in recent aquaculture production. To study the use of probiotics in the treatment of infectious diseases, the establishment of a method of experimental infection to obtain consistent results for mortality and infection in challenge tests is important. In pathogen-screening tests, 4 candidate pathogenic bacteria strains (Edwardsiella ictaluri gly09, E. ictaluri gly10, E. tarda LMG2793 and Streptococcus agalactiae LMG15977) were individually tested on xenic Nile tilapia larvae. Only Edwardsiella strains delivered via Artemia nauplii, with or without additional pathogen delivery via the culture water, led to increased mortality in fish larvae. A gnotobiotic Nile tilapia larvae model system was developed to provide a research tool to investigate the effects and modes-of-action of probiotics under controlled conditions. A double disinfection procedure using hydrogen peroxide and sodium hypochlorite solution was applied to the fish eggs, which were subsequently incubated in a cocktail of antibiotic and antifungal agents. In the gnotobiotic challenge test, E. ictaluri gly09R was added to the model system via Artemia nauplii and culture water, resulting in a significant mortality of the gnotobiotic fish larvae. The developed gnotobiotic Nile tilapia model can be used as a tool to extend understanding of the mechanisms involved in host-microbe interactions and to evaluate new methods of disease control.

  15. Origin and Genetic Diversity of Diploid Parthenogenetic Artemia in Eurasia

    PubMed Central

    Maccari, Marta; Amat, Francisco; Gómez, Africa

    2013-01-01

    There is wide interest in understanding how genetic diversity is generated and maintained in parthenogenetic lineages, as it will help clarify the debate of the evolution and maintenance of sexual reproduction. There are three mechanisms that can be responsible for the generation of genetic diversity of parthenogenetic lineages: contagious parthenogenesis, repeated hybridization and microorganism infections (e.g. Wolbachia). Brine shrimps of the genus Artemia (Crustacea, Branchiopoda, Anostraca) are a good model system to investigate evolutionary transitions between reproductive systems as they include sexual species and lineages of obligate parthenogenetic populations of different ploidy level, which often co-occur. Diploid parthenogenetic lineages produce occasional fully functional rare males, interspecific hybridization is known to occur, but the mechanisms of origin of asexual lineages are not completely understood. Here we sequenced and analysed fragments of one mitochondrial and two nuclear genes from an extensive set of populations of diploid parthenogenetic Artemia and sexual species from Central and East Asia to investigate the evolutionary origin of diploid parthenogenetic Artemia, and geographic origin of the parental taxa. Our results indicate that there are at least two, possibly three independent and recent maternal origins of parthenogenetic lineages, related to A. urmiana and Artemia sp. from Kazakhstan, but that the nuclear genes are very closely related in all the sexual species and parthenogegetic lineages except for A. sinica, who presumable took no part on the origin of diploid parthenogenetic strains. Our data cannot rule out either hybridization between any of the very closely related Asiatic sexual species or rare events of contagious parthenogenesis via rare males as the contributing mechanisms to the generation of genetic diversity in diploid parthenogenetic Artemia lineages. PMID:24376692

  16. Origin and genetic diversity of diploid parthenogenetic Artemia in Eurasia.

    PubMed

    Maccari, Marta; Amat, Francisco; Gómez, Africa

    2013-01-01

    There is wide interest in understanding how genetic diversity is generated and maintained in parthenogenetic lineages, as it will help clarify the debate of the evolution and maintenance of sexual reproduction. There are three mechanisms that can be responsible for the generation of genetic diversity of parthenogenetic lineages: contagious parthenogenesis, repeated hybridization and microorganism infections (e.g. Wolbachia). Brine shrimps of the genus Artemia (Crustacea, Branchiopoda, Anostraca) are a good model system to investigate evolutionary transitions between reproductive systems as they include sexual species and lineages of obligate parthenogenetic populations of different ploidy level, which often co-occur. Diploid parthenogenetic lineages produce occasional fully functional rare males, interspecific hybridization is known to occur, but the mechanisms of origin of asexual lineages are not completely understood. Here we sequenced and analysed fragments of one mitochondrial and two nuclear genes from an extensive set of populations of diploid parthenogenetic Artemia and sexual species from Central and East Asia to investigate the evolutionary origin of diploid parthenogenetic Artemia, and geographic origin of the parental taxa. Our results indicate that there are at least two, possibly three independent and recent maternal origins of parthenogenetic lineages, related to A. urmiana and Artemia sp. from Kazakhstan, but that the nuclear genes are very closely related in all the sexual species and parthenogegetic lineages except for A. sinica, who presumable took no part on the origin of diploid parthenogenetic strains. Our data cannot rule out either hybridization between any of the very closely related Asiatic sexual species or rare events of contagious parthenogenesis via rare males as the contributing mechanisms to the generation of genetic diversity in diploid parthenogenetic Artemia lineages.

  17. A novel model of early development in the brine shrimp, Artemia franciscana, and its use in assessing the effects of environmental variables on development, emergence, and hatching.

    PubMed

    Neumeyer, Courtney H; Gerlach, Jamie L; Ruggiero, Kristin M; Covi, Joseph A

    2015-03-01

    The brine shrimp, Artemia (Crustacea, Anostraca), is a zooplankton that is commonly used in both basic and applied research. Unfortunately, Artemia embryos are often cultured under conditions that alter early development, and reports based on these cultures oversimplify or fail to describe morphological phenotypes. This is due in part to the lack of a comprehensive developmental model that is applicable to observations of live specimens. The objective of this study was to build and test a descriptive model of post-diapause development in Artemia franciscana using observations made with a standard dissecting microscope. The working model presented is the first to comprehensively place all known "abnormal" embryonic and naupliar phenotypes within the context of a classic hatching profile. Contrary to previous reports, embryos and nauplii with aberrant phenotypes often recover and develop normally. Oval prenauplii may emerge as normal prenauplii (E2 stage). A delay of this transition leads to incomplete hatching or direct hatching of first instar larvae with a curved thoracoabdomen. When hatching is incomplete, retained cuticular remnants are shed during the next molt, and a "normal" second instar larva is produced. By differentiating between molting events and gross embryonic patterning in live embryos, this new model facilitates fine time-scale analyses of chemical and environmental impacts on early development. A small increase in salinity within what is commonly believed to be a permissive range (20‰-35‰) produced aberrant morphology by delaying emergence without slowing development. A similar effect was observed by decreasing culture density within a range commonly applied in toxicological studies. These findings clearly demonstrate that morphological data from end-point studies are highly dependent on the time points chosen. An alternate assessment method is proposed, and the potential impact of heavy metals, hexachlorobenzene, Mirex, and cis

  18. Binding of white spot syndrome virus to Artemia sp. cell membranes.

    PubMed

    Feng, Shuying; Li, Guangda; Feng, Wenpo; Huang, Jie

    2013-10-01

    Using differential velocity centrifugation, cell membranes of Artemia sp. were prepared, and their binding to white spot syndrome virus (WSSV) was analyzed in vitro. The results indicated that WSSV can specifically bind to Artemia cell membranes, and that WSSV receptor very likely existed in this membrane, which suggested that Artemia sp. may be a reservoir of WSSV. This study investigated the specific WSSV binding site by performing competitive inhibition experiments using shrimp gill cell membranes to bind WSSV to Artemia cell membranes. The results showed that shrimp gill cell membranes had a distinct inhibition effect on the specific binding of Artemia cell membranes to WSSV. Thus, potentially similar WSSV receptors or binding sites existed on Artemia sp. cell membranes and shrimp gill cell membranes. Taken together, these findings may provide experimental basis for the development of an effective approach to controlling WSSV, and theoretical basis for the study of WSSV receptors.

  19. The swimming behavior of Artemia (Anostraca): new experimental and observational data.

    PubMed

    Anufriieva, Elena V; Shadrin, Nickolai V

    2014-12-01

    Artemia (Anostraca) is among the most primitive and ancient groups of crustaceans. Artemia spp. play a dominant role in the ecosystems of hypersaline waters, and often they are the only animals in these extreme biotopes. Most ethological studies on Artemia have been conducted on nauplii and metanauplii. We made ethological observations on Artemia under laboratory conditions and in the natural waters of Crimea, where we studied growth and ontogenetic changes of swimming behavior. Growth occurred during the first 50 days up to a size of 9.5-10.5mm, after which time the size did not increase (some females lived up to 6.5 months). A strong positive relation was found between maximal speed and individual length, which varied between 0.4 and 10.5mm; it may be approximated by the power equation: Vmax=1.205·K(0.820), where Vmax is the maximal speed of Artemia (in mms(-1)) of the length K (in mm). There is no similar relation between average speed and length of Artemia. The average speed of adults was 40-60% lower in environments with microalgae compared to media without food. The duration of the "riding position" for mating pairs of Artemia urmiana in our experiments varied from 10 to 27 days. In lakes we observed different Artemia aggregations varying in size and form. We conclude that the swimming behavior of Artemia is quite complex and diverse, and develops during ontogeny.

  20. Understanding Environmental Factors that Affect Violence in Salinas, California

    DTIC Science & Technology

    2009-12-01

    of Sworn Police Officers per Capita vs. Violence Rate.....................47 Figure 22. Salinas Parks & Recreation Budget vs. Violence Rate...75 Figure 41. Violence vs. Parks & Recreation Budget Scatterplot ......................................76 Figure 42. Violence vs. Library... National Gang Violence conference, Anaheim, California, July 22, 2009). 11 Stahl, “The Loading Zone,” 17. 12 California Department of Justice Bureau of

  1. Why join groups? Lessons from parasite-manipulated Artemia.

    PubMed

    Rode, Nicolas O; Lievens, Eva J P; Flaven, Elodie; Segard, Adeline; Jabbour-Zahab, Roula; Sanchez, Marta I; Lenormand, Thomas

    2013-04-01

    Grouping behaviours (e.g. schooling, shoaling and swarming) are commonly explicated through adaptive hypotheses such as protection against predation, access to mates or improved foraging. However, the hypothesis that aggregation can result from manipulation by parasites to increase their transmission has never been demonstrated. We investigated this hypothesis using natural populations of two crustacean hosts (Artemia franciscana and Artemia parthenogenetica) infected with one cestode and two microsporidian parasites. We found that swarming propensity increased in cestode-infected hosts and that red colour intensity was higher in swarming compared with non-swarming infected hosts. These effects likely result in increased cestode transmission to its final avian host. Furthermore, we found that microsporidian-infected hosts had both increased swarming propensity and surfacing behaviour. Finally, we demonstrated using experimental infections that these concurrent manipulations result in increased spore transmission to new hosts. Hence, this study suggests that parasites can play a prominent role in host grouping behaviours.

  2. Possibilities of alternative generation II biotests at Artemia.

    PubMed

    Dvořák, Petr; Zďárský, Michal; Beňová, Katarína

    2009-06-01

    The meaning of alternative biotests is described and discussed. The paper also deals with the possible application of the developmental studies of the sea Artemia franciscana nauplinus. Five-day biotests including the validation criteria are described. The possibilities of the biotests are very wide. Additionally to the standard applications in ecotoxicology, there is a possibility of modelling pharmacological experiments or monitoring the effects of ionizing radiation and the interaction with other chemicals.

  3. Development of digestive enzyme activity in larvae of spotted sand bass Paralabrax maculatofasciatus. 1. Biochemical analysis.

    PubMed

    Alvarez-González, C A; Moyano-López, F J; Civera-Cerecedo, R; Carrasco-Chávez, V; Ortiz-Galindo, J L; Dumas, S

    2008-12-01

    Spotted sand bass Paralabrax maculatofasciatus is a potential aquaculture species in Northwest Mexico. In the last few years it has been possible to close its life cycle and to develop larviculture technology at on pilot scale using live food, however survival values are low (11%) and improvements in growth and survival requires the study of the morpho-physiological development during the initial ontogeny. In this research digestive activity of several enzymes were evaluated in larvae, from hatching to 30 days after hatching (dah), and in live prey (rotifers and Artemia), by use of biochemical and electrophoretic techniques. This paper, is the first of two parts, and covers only the biochemical analysis. All digestive enzyme activities were detected from mouth opening; however the, maximum activities varied among different digestive enzymes. For alkaline protease and trypsin the maximum activities were detected from 12 to 18 dah. Acid protease activity was observed from day 12 onwards. The other digestive enzymes appear between days 4 and 18 after hatching, with marked fluctuations. These activities indicate the beginning of the juvenile stage and the maturation of the digestive system, in agreement with changes that occur during morpho-physiological development and food changes from rotifers to Artemia. All enzymatic activities were detected in rotifers and Artemia, and their contribution to enhancement the digestion capacity of the larvae appears to be low, but cannot be minimised. We concluded that the enzymatic equipment of P. maculatofasciatus larvae is similar to that of other marine fish species, that it becomes complete between days 12 and 18 after hatching, and that it is totally efficient up to 25 dah.

  4. Characterization of the bis(5'-nucleosidyl) tetraphosphate pyrophosphohydrolase from encysted embryos of the brine shrimp Artemia.

    PubMed Central

    Prescott, M; Milne, A D; McLennan, A G

    1989-01-01

    The P1P4-bis(5'-nucleosidyl) tetraphosphate asymmetrical-pyrophosphohydrolase from encysted embryos of the brine shrimp Artemia has been purified over 11,000-fold to homogeneity. Anion-exchange chromatography resolves two major species with very similar properties. The enzyme is a single polypeptide of Mr 17,600 and is maximally active at pH 8.4 and 2 mM-Mg2+. It is inhibited by Ca2+ (IC50 = 0.9 mM with 2 mM-Mg2+) but not by Zn2+ ions. It preferentially hydrolyses P1P4-bis(5'-nucleosidyl) tetraphosphates, e.g. P1P4-bis(5'-adenosyl) tetraphosphate (Ap4A) (kcat. = 12.7 s-1; Km = 33 microM) and P1P4-bis(5'-guanosyl) tetraphosphate (Gp4G) (kcat. = 6.2 s-1; Km = 5 microM). With adenosine 5'-P1-tetraphospho-P4-5"'-guanosine (Ap4G) as substrate, there is a 4.5-fold preference for AMP and GTP as products and biphasic reaction kinetics are observed giving Km values of 4.7 microM and 34 microM, and corresponding rate constants of 6.5 s-1 and 11.9 s-1. The net rate constant for Ap4G hydrolysis is 7.6 s-1. The enzyme will also hydrolyse nucleotides with more than four phosphate groups, e.g. Ap5G, Ap6A and Gp5G are hydrolysed at 25%, 18% and 10% of the rate of Ap4A respectively. An NTP is always one of the products. Ap2A and Gp2G are not hydrolysed, while Ap3A and Gp3G are very poor substrates. When the enzyme is partially purified from embryos and larvae at different stages of development by sedimentation through a sucrose density gradient, its activity increases 3-fold during the first 12 h of pre-emergence development. This is followed by a slow decline during subsequent larval development. The similarity of this enzyme to other asymmetrical-pyrophosphohydrolases suggests that it did not evolve specifically to degrade the large yolk platelet store of Gp4G which is found in Artemia embryos, but that it probably serves the same general function in bis(5'-nucleosidyl) oligophosphate metabolism as in other cells. Images Fig. 3. PMID:2543371

  5. Working with dauer larvae.

    PubMed

    Karp, Xantha

    2016-07-14

    Dauer diapause is a stress-resistant, developmentally quiescent, and long-lived larval stage adopted by Caenorhabditis elegans when conditions are unfavorable for growth and reproduction. This chapter contains methods to induce dauer larva formation, to isolate dauer larvae, and to study pre- and post-dauer stages.

  6. Priming the prophenoloxidase system of Artemia franciscana by heat shock proteins protects against Vibrio campbellii challenge.

    PubMed

    Baruah, Kartik; Ranjan, Jayant; Sorgeloos, Patrick; Macrae, Thomas H; Bossier, Peter

    2011-07-01

    Like other invertebrates, the brine shrimp Artemia franciscana relies solely on innate immunity, which by definition lacks adaptive characteristics, to combat against invading pathogens. One of the innate mechanisms is melanisation of bacteria mediated by the activation of the prophenoloxidase (proPO) system. The 70 kDa heat shock proteins (Hsp70) derived from either prokaryote (Escherichia coli) or eukaryote (Artemia), well conserved and immune-dominant molecules, protect Artemia against Vibrio campbellii. However, the molecular mechanisms by which these proteins protect Artemia against Vibrio campbellii infection are unknown. Here we demonstrated that feeding gnotobiotically grown Artemia with either Artemia Hsp70 or the E. coli Hsp70 equivalent DnaK, each overproduced in E. coli, followed by V. campbellii challenge enhanced the proPO system, at both mRNA and protein activity levels. Additionally, the Artemia fed with these proteins survived well in a Vibrio challenge assay. These results indicated that Hsp70s derived from either prokaryotic or eukaryotic sources generate protective immunity in the crustacean Artemia against V. campbellii infection by priming the proPO system. This is apparently the first in vivo report on priming activity of Hsp70 in an invertebrate.

  7. Isolation of TDA-producing Phaeobacter strains from sea bass larval rearing units and their probiotic effect against pathogenic Vibrio spp. in Artemia cultures.

    PubMed

    Grotkjær, Torben; Bentzon-Tilia, Mikkel; D'Alvise, Paul; Dourala, Nancy; Nielsen, Kristian Fog; Gram, Lone

    2016-05-01

    Fish-pathogenic Vibrio can cause large-scale crashes in marine larval rearing units and, since the use of antibiotics can result in bacterial antibiotic resistance, new strategies for disease prevention are needed. Roseobacter-clade bacteria from turbot larval rearing facilities can antagonize Vibrio anguillarum and reduce mortality in V. anguillarum-infected cod and turbot larvae. In this study, it was demonstrated that antagonistic Roseobacter-clade bacteria could be isolated from sea bass larval rearing units. In addition, it was shown that they not only antagonized V. anguillarum but also V. harveyi, which is the major bacterial pathogen in crustaceans and Mediterranean sea bass larvae cultures. Concomitantly, they significantly improved survival of V. harveyi-infected brine shrimp. 16S rRNA gene sequence homology identified the antagonists as Phaeobacter sp., and in silico DNA-DNA hybridization indicated that they could belong to a new species. The genomes contained genes involved in synthesis of the antibacterial compound tropodithietic acid (TDA), and its production was confirmed by UHPLC-TOFMS. The new Phaeobacter colonized live feed (Artemia) cultures and reduced Vibrio counts significantly, since they reached only 10(4)CFUmL(-1), as opposed to 10(8)CFUmL(-1) in non-Phaeobacter treated controls. Survival of V. anguillarum-challenged Artemia nauplii was enhanced by the presence of wild type Phaeobacter compared to challenged control cultures (89±1.0% vs 8±3.2%). In conclusion, TDA-producing Phaeobacter isolated from Mediterranean marine larviculture are promising probiotic bacteria against pathogenic Vibrio in crustacean live-feed cultures for marine fish larvae.

  8. Daily feeding and protein metabolism rhythms in Senegalese sole post-larvae

    PubMed Central

    Yúfera, Manuel; Engrola, Sofia

    2017-01-01

    ABSTRACT Fish hatcheries must adapt larval feeding protocols to feeding behavior and metabolism patterns to obtain more efficient feed utilization. Fish larvae exhibit daily ingesting rhythms rather than ingesting food continuously throughout the day. The aim of this study was to determine the daily patterns of feed intake, protein digestibility, protein retention and catabolism in Senegalese sole post-larvae (Solea senegalensis; 33 days post-hatching) using 14C-labeled Artemia protein and incubation in metabolic chambers. Sole post-larvae were fed at 09:00, 15:00, 21:00, 03:00 and 09:00+1 day; and those fed at 09:00, 21:00, 03:00 and 09:00+1 day showed significantly higher feed intake than post-larvae fed at 15:00 h (P=0.000). Digestibility and evacuation rate of ingested protein did not change during the whole cycle (P=0.114); however, post-larvae fed at 21:00 and 03:00 h showed the significantly highest protein retention efficiency and lowest catabolism (P=0.002). Therefore, results confirm the existence of daily rhythmicity in feeding activity and in the utilization of the ingested nutrients in Senegalese sole post-larvae. PMID:27895049

  9. Assessment of fluorescent-labeled bacteria for evaluation of in vivo uptake of bacteria (Vibrio spp.) by crustacean larvae.

    PubMed

    Soto-Rodriguez, S A; Simões, N; Jones, D A; Roque, A; Gomez-Gil, B

    2003-01-01

    Available methods to study crustacean digestive tract colonization by bacteria are laborious, time-consuming, and do not permit in vivo assays and observation. This paper reports on a rapid and consistent technique to apply a fluorescent label to bacteria, which can then be presented to filter-feeding crustacea such as Artemia and penaeid larvae for later in situ bacterial distribution observation. Three luminescent Vibrio spp. were stained and observed inside Artemia nauplii, shrimp zoea and mysis stages, Vibrio harveyi type strain ATCC 14126, M(1) (pathogenic) and Ea (non-pathogenic). Factors such as dye (DTAF) concentration, exposure time/temperature and sonication time were evaluated. Viability of the dye and stained bacteria were tested at 4, -20 and -70 degrees C storage temperatures for up to 81 days. Results show that 4 and -20 degrees C storage temperatures are not recommended. At -70 degrees C, both bacteria and dye are optimally preserved. Monodispersed fluorescent-labeled bacterial cells can be observed inside the digestive tract of crustacean larvae at a density of inoculation as high as 5.2 x 10(6) CFU ml(-1). After 2 to 4 h, some leaching occurs, increasing difficulty in observation, although after 24 h, it is still possible to observe monodispersed FLB inside the digestive tract of crustacean larvae. Autofluorescence may complicate observation when filter-feeding crustacean larvae are co-fed with microalgae.

  10. Effect of Artemia franciscana on the removal of nickel by bioaccumulation.

    PubMed

    Devi, S Sujatha; Sethu, M; Priya, P Gomathi

    2014-01-01

    The present study evaluates the feasibility of using Artemia franciscana in reducing the Ni concentration of synthetic wastewater by the process of bioaccumulation. Metallothionein protein plays a key role in the uptake of nickel by Artemia. Artemia (Brine shrimp) was exposed to an initial nickel concentration of 40 mg/L. Gradual decrease of nickel was observed from 40 mg/L to 5 mg/L with a removal efficiency of 87.5%. The number of organisms were varied to determine the number for the maximum removal efficiency. Metallothionein protein in Artemia was estimated by the silver saturation method. The physical parameters such as pH were maintained in an alkaline condition of 9-10, temperature was maintained at room temperature and salinity at 30-35‰. These were found to be the optimal conditions for the survival and reduction of nickel by Artemia.

  11. A new method for the study of essential fatty acid requirements in fish larvae.

    PubMed

    Morais, Sofia; Conceição, Luís E C

    2009-05-01

    This study describes a methodology with potential application in the estimation of essential fatty acid (EFA) requirements of fish larvae. Senegalese sole (Solea senegalensis) larvae were fed, from 16 days after hatching (DAH), on Artemia enriched with different oils, inducing graded dietary concentrations of DHA: (1) soyabean oil, containing no measurable amounts of DHA (NDHA); (2) fish oil, inducing a medium DHA level (MDHA, 3 g DHA/100 g fatty acids); and (3) a mixture of Easy DHA Selco and Microfeed, resulting in high DHA content (HDHA, 8 g/100 g). At 28 DAH a metabolic trial was conducted where larvae were tube fed [1-(14) C]DHA, in order to determine its absorption, retention in the gut and body tissues, as well as its oxidation. At 23 DAH the HDHA treatment induced a significantly higher larval growth, while at 32 DAH significant differences were only found between the NDHA and HDHA treatments. The absorption of tube-fed [1-(14) C]DHA was extremely high (94-95 %) and independent of feeding regime. However, in larvae fed NDHA Artemia, a significantly higher amount of label was retained in the gut compartment and a concurrently lower retention was measured in the body. A significantly higher proportion of the absorbed DHA label was oxidized in larvae fed HDHA, compared to NDHA. Based on these results, we suggest that increasing dietary supply of DHA above the larval requirement level results in its increased oxidation for energy purposes and we propose potential applications of the tube feeding methodology using radiolabelled EFA in conjunction with dose-response studies.

  12. Longitudinal Analysis of Microbiota in Microalga Nannochloropsis salina Cultures.

    PubMed

    Geng, Haifeng; Sale, Kenneth L; Tran-Gyamfi, Mary Bao; Lane, Todd W; Yu, Eizadora T

    2016-07-01

    Large-scale open microalgae cultivation has tremendous potential to make a significant contribution to replacing petroleum-based fuels with biofuels. Open algal cultures are unavoidably inhabited with a diversity of microbes that live on, influence, and shape the fate of these ecosystems. However, there is little understanding of the resilience and stability of the microbial communities in engineered semicontinuous algal systems. To evaluate the dynamics and resilience of the microbial communities in microalgae biofuel cultures, we conducted a longitudinal study on open systems to compare the temporal profiles of the microbiota from two multigenerational algal cohorts, which include one seeded with the microbiota from an in-house culture and the other exogenously seeded with a natural-occurring consortia of bacterial species harvested from the Pacific Ocean. From these month-long, semicontinuous open microalga Nannochloropsis salina cultures, we sequenced a time-series of 46 samples, yielding 8804 operational taxonomic units derived from 9,160,076 high-quality partial 16S rRNA sequences. We provide quantitative evidence that clearly illustrates the development of microbial community is associated with microbiota ancestry. In addition, N. salina growth phases were linked with distinct changes in microbial phylotypes. Alteromonadeles dominated the community in the N. salina exponential phase whereas Alphaproteobacteria and Flavobacteriia were more prevalent in the stationary phase. We also demonstrate that the N. salina-associated microbial community in open cultures is diverse, resilient, and dynamic in response to environmental perturbations. This knowledge has general implications for developing and testing design principles of cultivated algal systems.

  13. Longitudinal analysis of microbiota in microalga Nannochloropsis salina cultures

    DOE PAGES

    Geng, Haifeng; Sale, Kenneth L.; Tran-Gyamfi, Mary Bao; ...

    2016-03-08

    Here, large-scale open microalgae cultivation has tremendous potential to make a significant contribution to replacing petroleum-based fuels with biofuels. Open algal cultures are unavoidably inhabited with a diversity of microbes that live on, influence, and shape the fate of these ecosystems. However, there is little understanding of the resilience and stability of the microbial communities in engineered semicontinuous algal systems. To evaluate the dynamics and resilience of the microbial communities in microalgae biofuel cultures, we conducted a longitudinal study on open systems to compare the temporal profiles of the microbiota from two multigenerational algal cohorts, which include one seeded withmore » the microbiota from an in-house culture and the other exogenously seeded with a natural-occurring consortia of bacterial species harvested from the Pacific Ocean. From these month-long, semicontinuous open microalga Nannochloropsis salina cultures, we sequenced a time-series of 46 samples, yielding 8804 operational taxonomic units derived from 9,160,076 high-quality partial 16S rRNA sequences. We provide quantitative evidence that clearly illustrates the development of microbial community is associated with microbiota ancestry. In addition, N. salina growth phases were linked with distinct changes in microbial phylotypes. Alteromonadeles dominated the community in the N. salina exponential phase whereas Alphaproteobacteria and Flavobacteriia were more prevalent in the stationary phase. We also demonstrate that the N. salina-associated microbial community in open cultures is diverse, resilient, and dynamic in response to environmental perturbations. This knowledge has general implications for developing and testing design principles of cultivated algal systems.« less

  14. Enhanced resistance against Vibrio harveyi infection by carvacrol and its association with the induction of heat shock protein 72 in gnotobiotic Artemia franciscana.

    PubMed

    Baruah, Kartik; Norouzitallab, Parisa; Phong, Ho Phuong Pham Duy; Smagghe, Guy; Bossier, Peter

    2017-03-16

    Induction of HSP72 is a natural response of stressed organisms that protects against many insults including bacterial diseases in farm (aquatic) animals. It would therefore be of great health benefit to search for natural compounds that are clinically safe yet able to induce HSP72 in animals. The phenolic compound carvacrol, an approved food component, had been shown in in vitro study to act as a co-inducer of HSP72, enhancing HSP72 production only in combination with a bona fide stress compared to the compound alone. However, in vitro model systems do not completely represent an in vivo physiology. Here, using the well-established gnotobiotic Artemia model system, we determined whether carvacrol could induce HSP72 in vivo, whether this putative effect could generate resistance in Artemia against biotic/abiotic stress and also unraveled the mechanism behind the possible HSP72-inducing effect of carvacrol. The gnotobiotic system is crucial for such studies because it avoids the interference of any extraneous factors on host-compound interaction. Here, carvacrol was shown to be a potent HSP72 inducer. Induction of HSP72 was associated with the generation of resistance in Artemia larvae against subsequent lethal heat stress or pathogenic Vibrio harveyi. Our results also provided new insight on the mode of HSP72 inducing action of carvacrol, in which the initial generation of reactive molecule H2O2 by the compound plays a key role. Overall results add new information about the bioactivity of carvacrol and advance our knowledge of this compound as potential prophylactic agent for controlling Vibrio infection in aquaculture animals.

  15. Historical Ground-Water Development in the Salinas Alluvial Fan Area, Salinas, Puerto Rico, 1900-2005

    USGS Publications Warehouse

    Rodriguez, Jose M.; Gómez-Gómez, Fernando

    2008-01-01

    The Salinas alluvial fan area has historically been one of the most intensively used agricultural areas in the South Coastal Plain of Puerto Rico. Changes in agricultural practices and land use in the Salinas alluvial fan have also caused changes in the geographic distribution of ground-water withdrawals from the alluvial aquifer. As a result, the ground-water balance and ground-water flow pattern have changed throughout the years and may explain the presence of saline ground water along parts of the coast at present. By providing a reconstruction of historical ground-water development in the Salinas alluvial fan area, from the initial years of aquifer development at about 1900 to the most recent conditions existing in 2005, water resources managers and planners can use the results of the analysis for a more complete understanding of aquifer conditions especially pertaining to water quality. This study effort was conducted by the U.S. Geological Survey in cooperation with the Puerto Rico Department of Natural and Environmental Resources as a contribution in the management of the Jobos Bay National Estuarine Research Reserve. The study area encompasses about 20 mi2 (square miles) of the extensive South Coastal Plain alluvial aquifer system (fig. 1). The study area is bounded to the north by foothills of the Cordillera Central mountain chain, to the south by the Caribbean Sea, and to the east and west by the Rio Nigua de Salinas and the Quebrada Aguas Verdes, respectively. Fan-delta and alluvial deposits contain the principal aquifers in the study area.

  16. Visceral larva migrans

    MedlinePlus

    ... with certain parasites found in the intestines of dogs and cats. Causes Visceral larva migrans (VLM) is ... parasites) that are found in the intestines of dogs and cats. Eggs produced by these worms are ...

  17. Determination in oocytes of the reproductive modes for the brine shrimp Artemia parthenogenetica.

    PubMed

    Dai, Zhong-Min; Li, Ran; Dai, Li; Yang, Jin-Shu; Chen, Su; Zeng, Qing-Guo; Yang, Fan; Yang, Wei-Jun

    2011-02-01

    The brine shrimp, Artemia, reproduces either oviparously, producing encysted embryos (diapause cysts), or ovoviviparously, producing free-swimming nauplii. Environmental factors, such as photoperiod, have been applied to control the reproduction mode of Artemia, but when the determination of a reproductive mode occurs remains unknown. We analysed the differential gene expression between oocytes from oviparous and ovoviviparous Artemia reared under different photoperiods. A total of 692 qualified cDNA clones were obtained by subtractive hybridization, 327 of which matched GenBank® Nucleotide Sequence Database entries. Gene expressions of 44 cDNAs (representing 56 clones) were analysed in oocytes using real-time PCR. Among these genes, 11 (21 clones) were significantly (P<0.05) up-regulated and 7 (9 clones) down-regulated in Artemia oocytes that subsequently enter diapause. Remarkably, known diapause-related proteins such as ArHsp22 (Artemia heat-shock protein 22) and chitin-binding proteins are found to be already differentially expressed. Furthermore, RNAi (RNA interference) knockdown of a differentially expressed gene, polo-like kinase 1, in oocyte of ovoviviparous Artemia led to the production of white embryos rather than free-swimming nauplii. In summary, our results provide evidence at the molecular level that the reproductive mode of Artemia is already determined at the oocyte stage of their life cycle.

  18. Nucleotide enrichment of live feed: a promising protocol for rearing of Atlantic cod Gadus morhua larvae.

    PubMed

    Lanes, Carlos Frederico Ceccon; Bolla, Sylvie; Fernandes, Jorge M O; Nicolaisen, Ove; Kiron, Viswanath; Babiak, Igor

    2012-10-01

    We investigated the effect of two commercial nucleotide products (NT1 and NT2), administered through live feed, on growth and stress tolerance of Atlantic cod larvae. Expression of genes related to muscle growth (igf-1, igf1r, igf-2, fst, fgf6, myod, and myhc) and nucleotide metabolism (uox, hprt, ndk, and uck) was evaluated during larval development. In addition, the expression of genes related to stress (hif-1α, hif-2α, hif-3α, and mb) was studied after an air exposure stress test. The enrichment of rotifers with nucleotides did not reveal any difference in nucleotide profiles, the exception being the RNA level of the NT1-enriched group that was significantly higher than the unenriched rotifer. Unenriched Artemia showed poor nucleotide profiles compared to enriched Artemia since 5' UMP, 5' GMP, and 5' AMP were observed only in the nucleotide groups. At 38 days post-hatch (dph), NT1 group had significantly higher dry weight (3.1 ± 0.1 mg) than the control (CON; 2.3 ± 0.1 mg). The treatments did not produce any significant differences in the expression of the key myogenic genes. Among the genes associated with nucleotide metabolism, ndk was down-regulated in NT1 at 38 dph. In the air exposure test, survival was significantly higher in the CON (77 ± 6 %) than in NT1 (48 ± 3 %) and NT2 (50 ± 3 %). After air exposure, mb was expressed at lower levels in NT2 group, hif-2α was induced in NT1 group, and hif-3α was upregulated in all groups. Our findings indicate that the improvement in the nucleotide profile of Artemia upon nucleotide enrichment could eventuate in the rapid growth of larvae.

  19. Automixis in Artemia: solving a century-old controversy.

    PubMed

    Nougué, O; Rode, N O; Jabbour-Zahab, R; Ségard, A; Chevin, L-M; Haag, C R; Lenormand, T

    2015-12-01

    Parthenogenesis (reproduction through unfertilized eggs) encompasses a variety of reproduction modes with (automixis) or without (apomixis) meiosis. Different modes of automixis have very different genetic and evolutionary consequences but can be particularly difficult to tease apart. In this study, we propose a new method to discriminate different types of automixis from population-level genetic data. We apply this method to diploid Artemia parthenogenetica, a crustacean whose reproductive mode remains controversial despite a century of intensive cytogenetic observations. We focus on A. parthenogenetica from two western Mediterranean populations. We show that they are diploid and that markers remain heterozygous in cultures maintained up to ~36 generations in the laboratory. Moreover, parallel patterns of population-wide heterozygosity levels between the two natural populations strongly support the conclusion that diploid A. parthenogenetica reproduce by automictic parthenogenesis with central fusion and low, but nonzero recombination. This settles a century-old controversy on Artemia, and, more generally, suggests that many automictic organisms harbour steep within-chromosome gradients of heterozygosity due to a transition from clonal transmission in centromere-proximal regions to a form of inbreeding similar to self-fertilization in centromere-distal regions. Such systems therefore offer a new avenue for contrasting the genomic consequences of asexuality and inbreeding.

  20. Methodical aspects of rearing decapod larvae, Pagurus bernhardus (Paguridae) and Carcinus maenas (Portunidae)

    NASA Astrophysics Data System (ADS)

    Dawirs, R. R.

    1982-12-01

    Improved methods for experimental rearing of Pagurus bernhardus and Carcinus maenas larvae are presented. Isolated maintenance was found essential for reliable statistical evaluation of results obtained from stages older than zoea-1. Only by isolated rearing is it possible to calculate mean values ±95% confidence intervals of stage duration. Mean values (without confidence intervals) can only be given for group-reared larvae if mortality is zero. Compared to group rearing, isolated rearing led to better survival, shorter periods of development and stimulated growth. Due to different swimming behavior P. bernhardus zoeae needed larger water volumes than Carcinus maenas larvae. P. bernhardus zoeae were reared with best results when isolated in Petri dishes (ca. 50 ml). They fed on newly hatched brine shrimp nauplii ( Artemia spp.). P. bernhardus megalopa did not require any gastropod shell or substratum; it developed best in glass vials without any food. C. maenas larvae could be reared most sucessfully in glass vials (ca 20 ml) under a simulated day-night regime (LD 16:8); constant darkness had a detrimental effect on development, leading to prolonged stage-duration times. C. maenas larvae were fed a mixture of newly hatched brine shrimp naupli and rotifers ( Brachionus plicatilis).

  1. Baylisascaris Larva Migrans

    USGS Publications Warehouse

    Kazacos, Kevin R.; Abbott, Rachel C.; Van Riper, Charles

    2016-05-26

    SummaryBaylisascaris procyonis, the common raccoon roundworm, is the most commonly recognized cause of clinical larva migrans (LM) in animals, a condition in which an immature parasitic worm or larva migrates in a host animal’s tissues, causing obvious disease. Infection with B. procyonis is best known as a cause of fatal or severe neurologic disease that results when the larvae invade the brain, the spinal cord, or both; this condition is known as neural larva migrans (NLM). Baylisascariasis is a zoonotic disease, that is, one that is transmissible from animals to humans. In humans, B. procyonis can cause damaging visceral (VLM), ocular (OLM), and neural larva migrans. Due to the ubiquity of infected raccoons around humans, there is considerable human exposure and risk of infection with this parasite. The remarkable disease-producing capability of B. procyonis in animals and humans is one of the most significant aspects of the biology of ascarids (large roundworms) to come to light in recent years. Infection with B. procyonis has important health implications for a wide variety of free-ranging and captive wildlife, zoo animals, domestic animals, as well as human beings, on both an individual and population level. This report, eighth in the series of U.S. Geological Survey Circulars on zoonotic diseases, will help us to better understand the routes of Baylisascaris procyonis infections and how best to adequately monitor this zoonotic disease.

  2. Map showing springs in the Salina quadrangle, Utah

    USGS Publications Warehouse

    Covington, Harry R.

    1972-01-01

    A spring is “a place where, without the agency of man, water flows from a rock or soil upon the land or into a body of surface water” (Meinzer, 1923, p. 48).About 450 springs are located on this map. Locations and names are from the U.S. Forest Service maps (1963, 1964) and from topographic maps of the U.S. Geological Survey, both published and in preparation. There is considerable variation in geological occurrence of the springs and in quantity and chemical quality of the water that issues from them. Springs in the Salina quadrangle are more abundant where annual precipitation is 16 inches or more, although there are many springs in arid parts of the quadrangle as well.In the Salina quadrangle, springs are used most commonly for watering livestock. They are used also for irrigation and for domestic and municipal water supply. Several communities in Rabbit Valley, Grass Valley, and Sevier Valley depend on springs for all or part of their water supply.Quantity and quality of water are shown for those few springs for which data are available (Mundorff, 1971). Caution must be used in drinking from springs, especially in arid areas; the water commonly tastes bad and may cause illness.

  3. The reaction of European lobster larvae (Homarus gammarus) to different quality food: effects of ontogenetic shifts and pre-feeding history.

    PubMed

    Schoo, Katherina L; Aberle, Nicole; Malzahn, Arne M; Schmalenbach, Isabel; Boersma, Maarten

    2014-02-01

    Young larval stages of many organisms represent bottlenecks in the life-history of many species. The high mortality commonly observed in, for example, decapod larvae has often been linked to poor nutrition, with most studies focussing on food quantity. Here, we focus instead on the effects of quality and have investigated its effects on the nutritional condition of lobster larvae. We established a tri-trophic food chain consisting of the cryptophyte Rhodomonas salina, the calanoid copepod Acartia tonsa and larvae of the European lobster Homarus gammarus. In a set of experiments, we manipulated the C:N:P stoichiometry of the primary producers, and accordingly those of the primary consumer. In a first experiment, R. salina was grown under N- and P-limitation and the nutrient content of the algae was manipulated by addition of the limiting nutrient to create a food quality gradient. In a second experiment, the effect on lobster larvae of long- and short-term exposure to food of varying quality during ontogenetic development was investigated. The condition of the lobster larvae was negatively affected even by subtle N- and P-nutrient limitations of the algae. Furthermore, younger lobster larvae were more vulnerable to nutrient limitation than older ones, suggesting an ontogenetic shift in the capacity of lobster larvae to cope with low quality food. The results presented here might have substantial consequences for the survival of lobster larvae in the field, as, in the light of future climate change and re-oligotrophication of the North Sea, lobster larvae might face marked changes in temperature and nutrient conditions, thus significantly altering their condition and growth.

  4. Bacteria associated with Artemia spp. along the salinity gradient of the solar salterns at Eilat (Israel).

    PubMed

    Tkavc, Rok; Ausec, Luka; Oren, Aharon; Gunde-Cimerman, Nina

    2011-08-01

    The crustacean genus Artemia naturally inhabits various saline and hypersaline environments and is the most frequently laboratory-hatched animal for live feed in mari- and aquaculture. Because of its high economic importance, Artemia-bacteria interactions were so far studied mostly in laboratory strains. In this study, we focused our attention on the Artemia-associated microbiota in its natural environment in the solar salterns of Eilat, Israel. We applied a culture-independent method (clone libraries) to investigate the bacterial community structure associated with Artemia in five evaporation ponds with salinities from slightly above seawater (5%) to the point of saturation (32%), in two different developmental stages: in nauplii and in the intestine of adult animals. Bacteria found in naupliar and adult stages were classified within the Proteobacteria, Bacteroidetes, Firmicutes, Actinobacteria and Cyanobacteria. The halophilic proteobacterial genera Halomonas spp. and Salinivibrio spp. dominated the Artemia microbiota in both stages in all ponds. We also analysed a clone library of entire adult animals, revealing a novel bacterial phylogenetic lineage. This is the first molecular study of bacteria associated with two developmental stages of Artemia along a salinity gradient.

  5. Mercury accumulation and its effects an Artemia franciscana

    SciTech Connect

    Boia, C.M.; Duarte, A.C.

    1995-12-31

    The effects of mercury accumulation on the brine shrimp Artemia franciscona were studied by long term (1--2 months) laboratory bioassays, using mercury chloride as the contaminant and the algae, Tetraselmis suecica as the food. These experiments were part of a larger research project aiming to contribute to the knowledge on mercury accumulation and its effects on Artemia. This crustacean is used worldwide for marine species feeding in aquafarms. This also happens on the lagoon of Aveiro, Portugal, which is partially contaminated with mercury. The first assays were conducted with concentrations of HgCl{sub 2} of the order of magnitude of those found in the waters of the lagoon of Aveiro (1.4 and 2.8 {micro}g/l). In further bioassays ranges of concentrations with observable effects have been used, from 0.02 to 1 mo. In the different assays the HgCl{sub 2} was: (a) simultaneously added to all the tanks or along the time, to evaluate the effects over different life stages (b) added directly to the tanks and then to the algae, at the same or in different quantities, to find out which was the more important pathway of contamination (c) removed from the feed stream after a certain time, to find out if detoxification would occur. The bioassays were carried out in five 100 l tanks under controlled temperature, pH, dissolved oxygen, salinity and feeding rate. Besides the content in mercury, size and number of the organisms have also been measured, as well as their content in total proteins, carbohydrates and fats.

  6. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages

    PubMed Central

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin

    2015-01-01

    ABSTRACT Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development. PMID:26545964

  7. Acute toxicity impacts of Euphorbia hirta L extract on behavior, organs body weight index and histopathology of organs of the mice and Artemia salina

    PubMed Central

    Rajeh, Mohammad Abu Basma; Kwan, Yuet Ping; Zakaria, Zuraini; Latha, Lachimanan Yoga; Jothy, Subramanion L.; Sasidharan, Sreenivasan

    2012-01-01

    Background: The methanol extract of Euphorbia hirta L (Euphorbiaceae), which is used in traditional medicines, was tested for in vivo toxicity. Materials and Methods: In vivo brine shrimp lethality assay and oral acute toxicity study at single high dose of 5000 mg/kg and observation for 14 days in mice were used to study the toxic effect of E. hirta. Results: Brine shrimp lethality assay was used to calculate the median lethal concentration (LC50) of E. hirta (for leaves, stems, flowers and roots) methanolic extracts at concentrations from 100 to 0.07 mg/ml. The LC50 values of 1.589, 1.420, 0.206 and 0.0827 mg/ml were obtained for stems, leaves, flowers and roots, respectively. Potassium dichromate (the positive control) had LC50 value of 0.00758 mg/ml. The acute oral toxicity study of the leaf extract resulted in one third mortality and mild behavioral changes among the treated mice. No significant statistical differences found between body weight, relative (%) and absolute (g) organ weights of treated and untreated groups (P> 0.05). Gross and microscopic examination of the vital organ tissues revealed no differences between control and treated mice. All the tissues appeared normal. Conclusions: E. hirta leaves methanol extract has exhibited mild toxic effects in mice. PMID:22923956

  8. Salinas - An implicit finite element structural dynamics code developed for massively parallel platforms

    SciTech Connect

    BHARDWAJ, MANLJ K.; REESE,GARTH M.; DRIESSEN,BRIAN; ALVIN,KENNETH F.; DAY,DAVID M.

    2000-04-06

    As computational needs for structural finite element analysis increase, a robust implicit structural dynamics code is needed which can handle millions of degrees of freedom in the model and produce results with quick turn around time. A parallel code is needed to avoid limitations of serial platforms. Salinas is an implicit structural dynamics code specifically designed for massively parallel platforms. It computes the structural response of very large complex structures and provides solutions faster than any existing serial machine. This paper gives a current status of Salinas and uses demonstration problems to show Salinas' performance.

  9. The Dunaliella salina organelle genomes: large sequences, inflated with intronic and intergenic DNA

    SciTech Connect

    Smith, David R.; Lee, Robert W.; Cushman, John C.; Magnuson, Jon K.; Tran, Duc; Polle, Juergen E.

    2010-05-07

    Abstract Background: Dunaliella salina Teodoresco, a unicellular, halophilic green alga belonging to the Chlorophyceae, is among the most industrially important microalgae. This is because D. salina can produce massive amounts of β-carotene, which can be collected for commercial purposes, and because of its potential as a feedstock for biofuels production. Although the biochemistry and physiology of D. salina have been studied in great detail, virtually nothing is known about the genomes it carries, especially those within its mitochondrion and plastid. This study presents the complete mitochondrial and plastid genome sequences of D. salina and compares them with those of the model green algae Chlamydomonas reinhardtii and Volvox carteri. Results: The D. salina organelle genomes are large, circular-mapping molecules with ~60% noncoding DNA, placing them among the most inflated organelle DNAs sampled from the Chlorophyta. In fact, the D. salina plastid genome, at 269 kb, is the largest complete plastid DNA (ptDNA) sequence currently deposited in GenBank, and both the mitochondrial and plastid genomes have unprecedentedly high intron densities for organelle DNA: ~1.5 and ~0.4 introns per gene, respectively. Moreover, what appear to be the relics of genes, introns, and intronic open reading frames are found scattered throughout the intergenic ptDNA regions -- a trait without parallel in other characterized organelle genomes and one that gives insight into the mechanisms and modes of expansion of the D. salina ptDNA. Conclusions: These findings confirm the notion that chlamydomonadalean algae have some of the most extreme organelle genomes of all eukaryotes. They also suggest that the events giving rise to the expanded ptDNA architecture of D. salina and other Chlamydomonadales may have occurred early in the evolution of this lineage. Although interesting from a genome evolution standpoint, the D. salina organelle DNA sequences will aid in the development of a viable

  10. Artemia parthenogenetica (Branchiopoda: Anostraca) from the Large Aral Sea: Abundance, distribution, population structure and cyst production

    NASA Astrophysics Data System (ADS)

    Arashkevich, Elena G.; Sapozhnikov, P. V.; Soloviov, K. A.; Kudyshkin, T. V.; Zavialov, P. O.

    2009-03-01

    The brine shrimp Artemia parthenogenetica appeared in the Large Aral Sea (Central Asia) in 1998 when mineralization reached 63 ppt. Data on Artemia abundance and biomass, along with temperature and salinity measurements were collected in the western basin during 2002-2006, primarily in the autumn. During the study period, population density grew progressively, both in terms of number, from 250 to 1260 individuals per m 3, and in terms of biomass, from 0.3 to 1.3 g per m 3. In 2005, the population density and spatial distribution in the different parts of the sea (western and eastern basins and strait) was assessed. The horizontal distribution of the Artemia population was uniform in the deep central part of the western basin, although the distribution was quite patchy in the shallow coastal zone. Depth habitat of Artemia was restricted to the upper 20-25 m of depth, as the oxygen depletion and formation of anoxic layer prevented distribution of Artemia to the deeper waters. In autumn, all females reproduced oviparously, with an average clutch size of 30-35 eggs per female. The number of eggs in a clutch was positively correlated with female body length ( r2 = 0.36-0.44).

  11. Assessment of the production potential of an emerging Artemia population in the Aral Sea, Uzbekistan

    NASA Astrophysics Data System (ADS)

    Marden, Brad; Van Stappen, Gilbert; Musaev, Ablatdyin; Mirabdullayev, Iskandar; Joldasova, Iliya; Sorgeloos, Patrick

    2012-04-01

    The objective of this study was to provide information on the developing parthenogenetic Artemia population in the Uzbek part of the Aral Sea, and to assess its potential for commercial exploitation. A sampling campaign was designed for abiotic factors (temperature, salinity, transparency) and Artemia population parameters at least once monthly in the period March-October of the years 2005-2007. By 2007 salinity in both basins had increased to values above 100 g l - 1 . Moreover, by 2007, desiccation had rendered the eastern Aral basin practically inaccessible for sampling or cyst harvesting. The volume of the western basin remained considerable, given its depth, with a relatively accessible shoreline. Average Artemia population parameters (e.g. adult abundance < 0.5 adults l - 1 ; 10-25 cysts brood - 1 ; cyst abundance < 5 and 10 cysts l - 1 for the western, resp. eastern basin) were low compared to Artemia sites of commercial importance. A gradual gain in population size in the western basin was observed over the period 2005-2007. The data further suggest that the low Artemia productivity is not genetically determined, but is largely the result of food limitation. The western basin may approach the threshold where a small-scale commercial operation is justified.

  12. Stress tolerance during diapause and quiescence of the brine shrimp, Artemia.

    PubMed

    MacRae, Thomas H

    2016-01-01

    Oviparously developing embryos of the brine shrimp, Artemia, arrest at gastrulation and are released from females as cysts before entering diapause, a state of dormancy and stress tolerance. Diapause is terminated by an external signal, and growth resumes if conditions are permissible. However, if circumstances are unfavorable, cysts enter quiescence, a dormant stage that continues as long as adverse conditions persist. Artemia embryos in diapause and quiescence are remarkably resistant to environmental and physiological stressors, withstanding desiccation, cold, heat, oxidation, ultraviolet radiation, and years of anoxia at ambient temperature when fully hydrated. Cysts have adapted to stress in several ways; they are surrounded by a rigid cell wall impermeable to most chemical compounds and which functions as a shield against ultraviolet radiation. Artemia cysts contain large amounts of trehalose, a non-reducing sugar thought to preserve membranes and proteins during desiccation by replacing water molecules and/or contributing to vitrification. Late embryogenesis abundant proteins similar to those in seeds and other anhydrobiotic organisms are found in cysts, and they safeguard cell organelles and proteins during desiccation. Artemia cysts contain abundant amounts of p26, a small heat shock protein, and artemin, a ferritin homologue, both ATP-independent molecular chaperones important in stress tolerance. The evidence provided in this review supports the conclusion that it is the interplay of these protective elements that make Artemia one of the most stress tolerant of all metazoan organisms.

  13. Functional differentiation of small heat shock proteins in diapause-destined Artemia embryos.

    PubMed

    King, Allison M; Toxopeus, Jantina; MacRae, Thomas H

    2013-10-01

    Encysted embryos of Artemia franciscana cease development and enter diapause, a state of metabolic suppression and enhanced stress tolerance. The development of diapause-destined Artemia embryos is characterized by the coordinated synthesis of the small heat shock proteins (sHsps) p26, ArHsp21 and ArHsp22, with the latter being stress inducible in adults. The amounts of sHsp mRNA and protein varied in Artemia cysts, suggesting transcriptional and translational regulation. By contrast to p26, knockdown of ArHsp21 by RNA interference had no effect on embryo development. ArHsp21 provided limited protection against stressors such as desiccation and freezing but not heat. ArHsp21 may have a non-essential or unidentified role in cysts. Injection of Artemia adults with amounts of ArHsp22 double-stranded RNA less than those used for other sHsps killed females and males, curtailing the analysis of ArHsp22 function in developing embryos and cysts. The results indicate that diapause-destined Artemia embryos synthesize varying amounts of sHsps as a result of differential gene expression and mRNA translation and also suggest that these sHsps have distinctive functions.

  14. Cross-linking of microtubules by microtubule-associated proteins (MAPs) from the brine shrimp, Artemia.

    PubMed

    Campbell, E J; MacKinlay, S A; MacRae, T H

    1989-05-01

    Microtubules induced with taxol to assemble in cell-free extracts of the brine shrimp, Artemia, are cross-linked by microtubule-associated proteins (MAPs). When the MAPs, extracted from taxol-stabilized microtubules with 1 M-NaCl are co-assembled with purified Artemia or mammalian neural tubulin, reconstitution of cross-linking between microtubules occurs. The most prominent non-tubulin protein associated with reconstituted cross-linked microtubules has a molecular weight of 49,000 but we cannot yet exclude the possibility that other proteins may be responsible for the cross-linking. Cross-linkers are separated by varying distances while cross-linked microtubules, prepared under different conditions, are 6.9-7.7 nm apart. Cross-linking of microtubules by MAPs occurs whether MAPs are added to assembling tubulin or to microtubules, and it is not disrupted by ATP. The MAPs are heat-sensitive and do not stabilize microtubules to cold. Immunological characterization of Artemia MAPs on Western blots indicates that Artemia lack MAP 1, MAP 2 and tau. Our results clearly demonstrate that Artemia contain novel MAPs with the ability to cross-link microtubules from phylogenetically disparate organisms in an ATP-independent manner.

  15. Interspecific competition and allelopathic interaction between Karenia mikimotoi and Dunaliella salina in laboratory culture

    NASA Astrophysics Data System (ADS)

    He, Dong; Liu, Jiao; Hao, Qiang; Ran, Lihua; Zhou, Bin; Tang, Xuexi

    2016-03-01

    Algal allelopathy is a manifold ecological/physiological phenomenon that is focused on chemical interactions and autotoxicity. We investigated the allelopathic interactions between Karenia mikimotoi and Dunaliella salina in laboratory cultures based on diff erent temperature (15°C, 20°C, and 25°C) and lighting (40, 80, and 160 μmol/(m2·s)) conditions. The growth of D. salina in bi-algae culture (1:1 size/density) was significantly restrained. The results of cell-free filtrate culture indicate that direct cell-tocell contact was not necessary in interspecific competition. Further experimental results demonstrated that allelochemicals released from K. mikimotoi were markedly influenced by both temperature ( P =0.013) and irradiance ( P =0.003), resulting in diff erent growth characteristics of D. salina in filtrate mediums. Compared with the plateau period, K. mikimotoi exudates in the exponential phase had a stronger short-term inhibition effect on D. salina in normal conditions. A clear concentration-dependent relationship was observed in the effect of allelochemicals released from K. mikimotoi with low-promoting and high-repressing effects on D. Salina in a short time-scale. In addition, allelopathic substances remain stable and effective under high temperature and pressure stress. Many flocculent sediments adhering with D. salina cells were observed in all filtrate mediums, while the quantity and color depended on the original culture conditions.

  16. Determination of extremely high pressure tolerance of brine shrimp larvae by using a new pressure chamber system.

    PubMed

    Seo, Mihye; Koyama, Sumihiro; Toyofuku, Takashi; Kojima, Shigeaki; Watanabe, Hiromi

    2013-11-01

    Hydrostatic pressure is the only one of a range of environmental parameters (water temperature, salinity, light availability, and so on) that increases in proportion with depth. Pressure tolerance is therefore essential to understand the foundation of populations and current diversity of faunal compositions at various depths. In the present study, we used a newly developed pressure chamber system to examine changes in larval activity of the salt-lake crustacean, Artemia franciscana, in response to a range of hydrostatic pressures. We showed that A. franciscana larvae were able to survive for a short period at pressures of ≤ 60 MPa (approximately equal to the pressure of 6000 m deep). At a pressure of > 20 MPa, larval motor ability was suppressed, but not lost. Meanwhile, at a pressure of > 40 MPa, some of the larval motor ability was lost without recovery after decompression. For all experiments, discordance of movement and timing between right and left appendages, was observed at pressures of > 20 MPa. Our results indicate that the limit of pressure for sustaining active behavior of A. franciscana larvae is ∼20 MPa, whereas the limit of pressure for survival is within the range 30-60 MPa. Thus, members of the genus Artemia possess the ability to resist a higher range of pressures than their natural habitat depth. Our findings demonstrated an example of an organism capable of invading deeper environment in terms of physical pressure tolerance, and indicate the need and importance of pressure study as an experimental method.

  17. Protein stability in Artemia embryos during prolonged anoxia.

    PubMed

    Clegg, James S

    2007-02-01

    Encysted embryos (cysts) of the brine shrimp, Artemia franciscana, are arguably the most stress-resistant of all animal life-history stages. One of their many adaptations is the ability to tolerate anoxia for periods of years, while fully hydrated and at physiological temperatures. Previous work indicated that the overall metabolism of anoxic embryos is brought to a reversible standstill, including the transduction of free energy and the turnover of macromolecules. But the issue of protein stability at the level of tertiary and quaternary structure was not examined. Here I provide evidence that the great majority of proteins do not irreversibly lose their native conformation during years of anoxia, despite the absence of detectable protein turnover. Although a modest degree of protein denaturation and aggregation occurs, that is quickly reversed by a brief post-anoxic aerobic incubation. I consider how such extraordinary stability is achieved and suggest that at least part of the answer involves massive amounts of a small heat shock protein (p26) that acts as a molecular chaperone, the function of which does not appear to require ribonucleoside di- or tri-phosphates.

  18. Gamma Radiation Reduced Toxicity of Azoxystrobin Tested on Artemia franciscana.

    PubMed

    Dvorak, P; Zdarsky, M; Benova, K; Falis, M; Tomko, M

    2016-06-01

    Fungicide azoxystrobin toxicity was monitored by means of a 96-h biotest with Artemia franciscana nauplius stages after exposure to solutions with concentrations of 0.2, 0.4, 0.6 and 0.8 mg L(-1) irradiated with (60)Co gamma radiation with doses of 1, 2.5, 5 and 10 kGy. The effects of ionization radiation on azoxystrobin toxicity were mainly manifested by a statistically significant reduction of lethality after 72- and 96-h exposure. A maximum reduction of lethality of 72 % was achieved using doses of 1-5 kGy for an azoxystrobin initial concentration of 0.4 mg L(-1) and after 72 h of exposure. At a 96-h exposure, a difference of lethal effects reached up to 70 % for a dose of 10 kGy. The observed effect of gamma ionizing radiation on azoxystrobin toxicity suggest that this approach can be applied as an alternative for a reduction of azoxystrobin residua in food.

  19. Nitrate Contamination of Deep Aquifers in the Salinas Valley, California

    NASA Astrophysics Data System (ADS)

    Moran, J. E.; Esser, B. K.; Hillegonds, D. J.; Holtz, M.; Roberts, S. K.; Singleton, M. J.; Visser, A.; Kulongoski, J. T.; Belitz, K.

    2011-12-01

    The Salinas Valley, known as 'the salad bowl of the world', has been an agricultural center for more than 100 years. Irrigated row crops such as lettuce and strawberries dominate both land use and water use. Groundwater is the exclusive supply for both irrigation and drinking water. Some irrigation wells and most public water supply wells in the Salinas Valley are constructed to draw water from deep portions of the aquifer system, where contamination by nitrate is less likely than in the shallow portions of the aquifer system. However, a number of wells with top perforations greater than 75 m deep, screened below confining or semi-confining units, have nitrate concentrations greater than the Maximum Contaminant Limit (MCL) of 45 mg/L as NO3-. This study uses nitrate concentrations from several hundred irrigation, drinking water, and monitoring wells (Monterey County Water Resources Agency, 1997), along with tritium-helium groundwater ages acquired at Lawrence Livermore National Laboratory through the State of California Groundwater Monitoring and Assessment (GAMA) program (reported in Kulongoski et al., 2007 and in Moran et al., in press), to identify nitrate 'hot spots' in the deep aquifer and to examine possible modes of nitrate transport to the deep aquifer. In addition, observed apparent groundwater ages are compared with the results of transport simulations that use particle tracking and a stochastic-geostatistical framework to incorporate aquifer heterogeneity to determine the distribution of travel times from the water table to each well (Fogg et al., 1999). The combined evidence from nitrate, tritium, tritiogenic 3He, and radiogenic 4He concentrations, reveals complex recharge and flow to the capture zone of the deep drinking water wells. Widespread groundwater pumping for irrigation accelerates vertical groundwater flow such that high nitrate groundwater reaches some deep drinking water wells. Deeper portions of the wells often draw in water that recharged

  20. Cestodes change the isotopic signature of brine shrimp, Artemia, hosts: implications for aquatic food webs.

    PubMed

    Sánchez, Marta I; Varo, Nico; Matesanz, Cristina; Ramo, Cristina; Amat, Juan A; Green, Andy J

    2013-01-01

    To reach the final host (greater flamingos), the cestode Flamingolepis liguloides alters the behaviour of its intermediate host, the brine shrimp, Artemia parthenogenetica, causing it to spend more time close to the water surface. During summer 2010, we showed that the prevalence of this cestode was consistently higher at the top of the water column in the Odiel salt pans in south-western Spain. We used stable nitrogen (N) and carbon (C) isotopic analysis to test the hypothesis that cestodes also alter resource use by Artemia. In early summer, we compared stable isotopes in infected hosts at the surface with those from uninfected hosts at the bottom of the water column. In late summer, we compared infected and uninfected Artemia from the bottom. δ(15)N was consistently enriched in infected individuals compared with uninfected hosts, especially in Artemia with multiple infections of F. liguloides (family Hymenolepididae) and those with mixed infections of F. liguloides and cestodes of the family Dilepididae. Infected individuals from the surface were enriched in δ(13)C compared with uninfected ones from the bottom, but the opposite was found when comparing uninfected and infected Artemia from the same depth. This may be caused by the increase in lipid concentration in infected Artemia. Isolated cysticercoids of F. liguloides were significantly enriched in δ(13)C compared with cysticercoids in infected hosts, but surprisingly were not enriched in N. Our findings illustrate the way cestodes can alter food webs and highlight the importance of considering the parasitic status of prey in studies of trophic ecology in saline wetlands.

  1. Characterization of vitamin B12 in Dunaliella salina.

    PubMed

    Kumudha, Anantharajappa; Sarada, Ravi

    2016-01-01

    Vitamin B12 is one of nature's complex metabolite which is industrially produced using certain bacteria. Algae could be an alternative source of vitamin B12 and in this study, vitamin B12 from a halotolerant green alga, Dunaliella salina V-101 was purified and characterized. The extract of Dunaliella was purified by passing through Amberlite XAD-2 and EASI-extract vitamin B12 immunoaffinity column. The total vitamin B12 content in purified sample fractions was 42 ± 2 μg/100 g dry weight as determined by the chemiluminescence method which was almost close to 49 ± 2 μg/100 g dry weight as estimated by microbiological method. Further quantification of total vitamin B12 using gold nanoparticle (AUNPs) based aptamer showed 40 ± 0.8/100 g dry weight. There was a good correlation among all the methods of quantification. Adenosylcobalamin, a form of vitamin B12 which is a cofactor for methylmalonyl CoA mutase was identified by HPLC. Upon quantification, Dunaliella was found to contain 34 ± 4 μg of adenosylcobalamin for 100 g dry biomass. Authenticity of adenosylcobalmin was confirmed by tandem mass spectrometry (MS/MS), selected ion recording (SIR) and multiple reaction monitoring (MRM) studies.

  2. Development of the brine shrimp Artemia is accelerated during spaceflight

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Metcalf, J.; DeBell, L.; Paulsen, A.; Noren, W.; Guikema, J. A.

    1994-01-01

    Developmentally arrested brine shrimp cysts have been reactivated during orbital spaceflight on two different Space Shuttle missions (STS-50 and STS-54), and their subsequent development has been compared with that of simultaneously reactivated ground controls. Flight and control brine shrimp do not significantly differ with respect to hatching rates or larval morphology at the scanning and transmission EM levels. A small percentage of the flight larvae had defective nauplier eye development, but the observation was not statistically significant. However, in three different experiments on two different flights, involving a total of 232 larvae that developed in space, a highly significant difference in degree of flight to control development was found. By as early as 2.25 days after reactivation of development, spaceflight brine shrimp were accelerated, by a full instar, over ground control brine shrimp. Although developing more rapidly, flight shrimp grew as long as control shrimp at each developmental instar or stage.

  3. Development of the brine shrimp Artemia is accelerated during spaceflight.

    PubMed

    Spooner, B S; Metcalf, J; DeBell, L; Paulsen, A; Noren, W; Guikema, J A

    1994-07-01

    Developmentally arrested brine shrimp cysts have been reactivated during orbital spaceflight on two different Space Shuttle missions (STS-50 and STS-54), and their subsequent development has been compared with that of simultaneously reactivated ground controls. Flight and control brine shrimp do not significantly differ with respect to hatching rates or larval morphology at the scanning and transmission EM levels. A small percentage of the flight larvae had defective nauplier eye development, but the observation was not statistically significant. However, in three different experiments on two different flights, involving a total of 232 larvae that developed in space, a highly significant difference in degree of flight to control development was found. By as early as 2.25 days after reactivation of development, spaceflight brine shrimp were accelerated, by a full instar, over ground control brine shrimp. Although developing more rapidly, flight shrimp grew as long as control shrimp at each developmental instar or stage.

  4. Therapeutic effect of Artemia enriched with Escherichia coli expressing double-stranded RNA in the black tiger shrimp Penaeus monodon.

    PubMed

    Thammasorn, Thitiporn; Somchai, Parinyachat; Laosutthipong, Chaowanee; Jitrakorn, Sarocha; Wongtripop, Somjai; Thitamadee, Siripong; Withyachumnarnkul, Boonsirm; Saksmerprome, Vanvimon

    2013-10-01

    We exploited Artemia as a double-stranded (ds)RNA-delivery system to combat viral diseases in shrimp. First, the transformed Escherichia coli (E. coli) expressing red fluorescent protein (RFP) was tested in the Artemia enrichment process. RFP signals detectable in the gut of Artemia under confocal microscope were evident for the successful encapsulation. Second, the Artemia enrichment process was performed using E. coli producing Laem-Singh virus (LSNV)-specific dsRNA, which has been previously shown to inhibit the viral infection in the black tiger shrimp Penaeus monodon by intramuscular injection and oral administration. The enriched Artemia nauplii were confirmed to contain dsRNA-LSNV by RT-PCR, and were subjected to the feeding test with P. monodon postlarvae. Quantitative RT-PCR indicated that a number of LSNV copies in most of the treated shrimp were, at least, 1000-fold lower than the untreated controls. During 11-17weeks after feeding, average body weight of the treated group was markedly increased relative to the control group. A smaller differential growth rate of the treated group as compared to the control was also noticed. These results suggested that feeding shrimp with the dsRNA-enriched Artemia can eliminate LSNV infection, which is the cause of retarded growth in P. monodon. The present study reveals for the first time the therapeutic effect of dsRNA-enriched Artemia for shrimp disease control.

  5. Isolation and characterization of the gene coding for Artemia franciscana TATA-binding protein: expression in cryptobiotic and developing embryos.

    PubMed

    Sastre, L

    1999-06-09

    Genomic and cDNA clones coding for the Artemia franciscana homolog of the TATA box-binding protein (TBP) were isolated. The C-terminal region of the predicted protein displays up to 92% sequence identity with the conserved C-terminal regions of TBPs from other species. The gene is divided in seven exons that expand over a region of 33 kb. The position of the four introns located in the conserved C-terminal region has been compared with those of other species. Two of these introns have been generally conserved during evolution, another is an arthropod specific intron, present in Drosophila melanogaster and A. franciscana, and the other is only conserved between vertebrates and A. franciscana. Primer extension experiments detected several transcription initiation sites. Northern blot analyses showed the presence of four mRNAs of estimated sizes of 6.8, 2.6, 1.6 and 1.1 kb. Except for the low expression of the 6.8 and 2. 6 kb RNAs in encysted embryos, steady-state levels showed little variation during the activation of the encysted embryo and the first steps of embryonic and larval development. The amount of TBP protein expressed in encysted embryos and developing larvae has been analyzed by Western blot. Cryptobiotic embryos contain significant amounts of TBP although the level of expression increased almost twice during the first 20 h of development. The presence of TBP protein in cryptobiotic embryos suggests that TBP does not play, by itself, a critical role in the arrest of transcription characteristic of these resistance forms.

  6. Characterization of novel nitrate reductase-deficient mutants for transgenic Dunaliella salina systems.

    PubMed

    Gao, L J; Jia, Y L; Li, S K; Qiu, L L

    2015-10-27

    The aim of the present study was to isolate and characterize novel nitrate reductase (NR)-deficient mutants, which may be useful for the transgenic manipulation of Dunaliella salina. Three NR-deficient mutants of D. salina, J-1, J-2, and J-3, were successfully isolated by screening for chlorate resistance after chemical mutagenesis with ethylnitrosourea. NR activity was not detected in the mutants and the expression of NR mRNA was significantly decreased. Growth analysis of D. salina strains grown in media containing different nitrogen sources revealed that these mutants were capable of utilizing nitrite and urea, but not nitrate as a nitrogen source, indicating that these mutants are indeed NR-deficient. Mutation analysis of NR cDNA sequences revealed that there were 11 point mutations shared by the J-1, J-2, and J-3 mutants. Furthermore, the results of the functional complementation experiment showed that NR activity of transformant T-1 derived from J-1 was recovered to 48.1 % of that of the wild-type D. salina. The findings of the present study indicate that nitrate may be used as a selective agent rather than antibiotics or herbicides for the isolated NR-deficient mutants in future transgenic D. salina systems.

  7. Bioconversion of omega-six to omega-three polyunsaturated fatty acids in Artemia

    SciTech Connect

    Omara-Alwala, T.R.

    1986-01-01

    A study was conducted to provide conclusive evidence for the bioconversion of 18:2W6 to 20:5W3 in Artemia and to establish a possible biosynthetic pathway responsible for the bioconversion. Except for fatty acid profile, the diet was considered complete in its nutritional quality. It was deficient in 20:5W3, an essential fatty acid for marine fish, but adequate in 18:3W3, an essential fatty acid for freshwater fish. The Artemia raised on the diet showed a high level of 20:5W3 with little accumulation of 18:3W3, making them the marine type. There were no mortalities throughout the 7-day feeding period. Two-day-old Artemia were fed for 7 days on either control diet or treatment diet with (1-/sup 14/C) 18:2W6, along with various unlabeled fatty acids. Data confirmed that Artemia were able to bioconvert 18:2W6 to 20:5W3. The following biosynthetic sequence was proposed for the bioconversion: 18:2W6 - 18:3W3 - 20:3W3 - 20:4W3 - 20:5W3. All possible multistep pathways for the synthesis of 20:5W3 from 18:2W6 were worked out for any feeding experiments using dietary 18:2W6.

  8. Effect of mercuric ion on attraction to light of artemia sp nauplii.

    PubMed

    Saunders, J P; Trieff, N M; Kalmaz, E E; Uchida, T

    1985-02-01

    Living organisms exhibit a phototactic response which can be altered by certain environmental toxic chemical species. The analysis of photobehavior can help in elucidating environmental factors that influence photomotility reactions of the organisms. A method has been developed that measures the phototactic response of Artemia nauplii under the influence of mercuric ion (Hg2+) in synthetic seawater. The phototactic response of Artemia nauplii was manifested by movement of the organisms from a darkened half to lighted half of an experimental vessel containing synthetic seawater. The density as a function of time of Artemia nauplii is determined by removing aliquots from both light and dark sides and then plating on agar for counting under the dissecting microscope. Measurements consistently show a significant movement of nauplii to the lighted side within 45 min of the start of the experiments. The present investigation demonstrated that at concentrations as low as 0.010 mg HgCl2/liter there is an enhancement of phototactic effect on Artemia nauplii by mercuric ion as compared with control. The phototactic response of Artema nauplii is altered by mercuric ion in a dose-related manner, but the mechanism of this effect is presently unknown.

  9. Immunodetection of thiol proteinase levels in various populations of Artemia cysts and during development.

    PubMed

    Lu, J; Warner, A H

    1991-01-01

    An immunodetection assay on Western blots has been used to determine the thiol proteinase content and composition in cysts from 12 populations of the brine shrimp Artemia. Our results showed no differences in the subunit composition of the thiol proteinase among cysts from eight bisexual strains and four parthenogenic strains, and confirmed an earlier finding that the proteinase is composed of two subunits of 25.9 and 31.5 kilodaltons. In contrast, we found that Artemia cysts from parthenogenic strains contain 17.1 ng/cyst of the thiol proteinase, while cysts from bisexual strains contain 8.2 ng/cyst of the thiol proteinase. Also, there was a good linear correlation (r = 0.863; p less than 0.001) between the thiol proteinase content and cyst mass. Embryo fractionation experiments showed that 82% of the thiol proteinase was in the cytosol, while 14 and 4%, respectively, were in the nuclei/yolk platelets and mitochondria/lysosome fractions. Measurements of the thiol proteinase content of developing Artemia embryos showed that the proteinase content was relatively constant during early development, suggesting that the activity of the thiol proteinase gene(s) may be constitutive and not developmentally regulated in Artemia embryos.

  10. Potential utilization of Artemia franciscana eggs as food for Coleomegilla maculata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the hypothesis that Artemia franciscana Kellogg (brine shrimp, Anostraca: Artemiidae) eggs are suitable factitious, i.e., alternative, food to support the life history of a predatory ladybird beetle, Coleomegilla maculata DeGeer (Coleoptera: Coccinellidae). Using progeny from a stock colo...

  11. A modern subtropical playa complex: Salina de Ambargasta, central Argentina

    NASA Astrophysics Data System (ADS)

    Zanor, Gabriela A.; Piovano, Eduardo L.; Ariztegui, Daniel; Vallet-Coulomb, Christine

    2012-04-01

    Salina de Ambargasta is a playa located at mid latitudes in central Argentina (29 °S-64 °W). Because of its hydrological behaviour, this playa complex can be subdivided into a closed system "sensu-stricto" and an "open-like system" due to the presence of a seasonal outflow. Geomorphological and sedimentological features enable the separation of the Ambargasta playa into well-defined western, eastern and northern zones, where aeolian processes, groundwater supply and surface inflow, respectively, define distinctive sedimentary environments and typical processes of deposition. The following depositional settings were recognized: (1) alluvial fan; (2) sandflat; (3) springs; (4) dunes and palaeo-dune field; (5) dry mudflat; (6) capillary mudflat; (7) ephemeral saline lake (includes saline mudflat and salt pan). The dry mudflat is present at the highest topographical zone, where the groundwater influence is less important and only intermittent ponds are present. In the capillary mudflat, evaporite sedimentation is limited to the development of efflorescence by evaporative pumping. The ephemeral saline lake, placed in the lowermost topographical region, alternates cycles of lake expansion and contraction responding to inter-annual hydrological variability as well as to seasonal variability. Lake expansion takes place during early austral summer (December-March), while continuous evaporation of brine leads to the growth of halite crystals during late summer. Sodium chloride-type brines result from both chemical fractionation as evaporation increases and salt dissolution. The isotopic compositions of surficial and underground waters (δ18O and δ2H) indicate that lake waters become isotopically enriched during summer when evaporation plays a significant role in the playa complex.

  12. Microgavage of Zebrafish Larvae

    PubMed Central

    Cocchiaro, Jordan L.; Rawls, John F.

    2013-01-01

    The zebrafish has emerged as a powerful model organism for studying intestinal development1-5, physiology6-11, disease12-16, and host-microbe interactions17-25. Experimental approaches for studying intestinal biology often require the in vivo introduction of selected materials into the lumen of the intestine. In the larval zebrafish model, this is typically accomplished by immersing fish in a solution of the selected material, or by injection through the abdominal wall. Using the immersion method, it is difficult to accurately monitor or control the route or timing of material delivery to the intestine. For this reason, immersion exposure can cause unintended toxicity and other effects on extraintestinal tissues, limiting the potential range of material amounts that can be delivered into the intestine. Also, the amount of material ingested during immersion exposure can vary significantly between individual larvae26. Although these problems are not encountered during direct injection through the abdominal wall, proper injection is difficult and causes tissue damage which could influence experimental results.We introduce a method for microgavage of zebrafish larvae. The goal of this method is to provide a safe, effective, and consistent way to deliver material directly to the lumen of the anterior intestine in larval zebrafish with controlled timing. Microgavage utilizes standard embryo microinjection and stereomicroscopy equipment common to most laboratories that perform zebrafish research. Once fish are properly positioned in methylcellulose, gavage can be performed quickly at a rate of approximately 7-10 fish/ min, and post-gavage survival approaches 100% depending on the gavaged material. We also show that microgavage can permit loading of the intestinal lumen with high concentrations of materials that are lethal to fish when exposed by immersion. To demonstrate the utility of this method, we present a fluorescent dextran microgavage assay that can be used to

  13. Isolation and proteomic analysis of the halotolerant alga Dunaliella salina flagella using shotgun strategy.

    PubMed

    Jia, Yanlong; Xue, Lexun; Li, Jie; Liu, Hongtao

    2010-02-01

    Previous studies have demonstrated that flagella/cilia are critical organelles and play diverse roles of motility, sensory perception and development in many eukaryotic cells. However, there is very little information available about flagella composition in Dunaliella salina, a halotolerant, unicellular biflagellate green alga. In the present study, we used strategy of shotgun proteomics to identify flagella proteins after flagella were released and collected from D. salina. A total of 520 groups of proteins were identified under a stringent filter condition (Xcorr > or =1.9, > or =2.2 and > or =3.75; DeltaCn >/= 0.1). In addition to six kinds of known flagella proteins, the putative flagella proteins of D. salina identified by one or more peptides are abundant in signaling, cell division, metabolism, etc. The findings provide guidance for further studies to elucidate the roles of these proteins in the function and assembly of this organelle in microalgae.

  14. Analysis of an essential carotenogenic enzyme: ζ-carotene desaturase from unicellular Alga Dunaliella salina.

    PubMed

    Ye, Zhi-Wei; Jiang, Jian-Guo

    2010-11-10

    The green alga Dunaliella has become a valuable model organism for understanding the interesting mechanism of massive carotenoid accumulation. Previously, DNA sequences of several carotenogenic enzymes were obtained from Dunaliella. In this study, the cDNA of zds was isolated from Dunaliella salina using a polymerase chain reaction approach. The full-length cDNA sequence was 2178 base pairs (bp) containing a 1731 bp putative open reading frame which coded a 576 amino acid deduced polypeptide whose molecular weight was 63.9 kDa computationally. A complete homologous search displayed that the nucleotide and putative protein sequence have sequence identities of 69% and 66% with those of green alga Chlamydomonas reinhardtii, respectively. It was predicted that this ζ-carotene desaturase (Zds) may be located in the chloroplast of D. salina. Phylogenetic analysis demonstrated that the D. salina Zds had a closer relationship with the Zds of algae and higher plants than with those of other species.

  15. A dynamic growth model of Dunaliella salina: parameter identification and profile likelihood analysis.

    PubMed

    Fachet, Melanie; Flassig, Robert J; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2014-12-01

    In this work, a photoautotrophic growth model incorporating light and nutrient effects on growth and pigmentation of Dunaliella salina was formulated. The model equations were taken from literature and modified according to the experimental setup with special emphasis on model reduction. The proposed model has been evaluated with experimental data of D. salina cultivated in a flat-plate photobioreactor under stressed and non-stressed conditions. Simulation results show that the model can represent the experimental data accurately. The identifiability of the model parameters was studied using the profile likelihood method. This analysis revealed that three model parameters are practically non-identifiable. However, some of these non-identifiabilities can be resolved by model reduction and additional measurements. As a conclusion, our results suggest that the proposed model equations result in a predictive growth model for D. salina.

  16. Feeding truncated heat shock protein 70s protect Artemia franciscana against virulent Vibrio campbellii challenge.

    PubMed

    Baruah, Kartik; Norouzitallab, Parisa; Shihao, Li; Sorgeloos, Patrick; Bossier, Peter

    2013-01-01

    The 70 kDa heat shock proteins (Hsp70s) are highly conserved in evolution, leading to striking similarities in structure and composition between eukaryotic Hsp70s and their homologs in prokaryotes. The eukaryotic Hsp70 like the DnaK (Escherichia coli equivalent Hsp70) protein, consist of three functionally distinct domains: an N-terminal 44-kDa ATPase portion, an 18-kDa peptide-binding domain and a C-terminal 10-kDa fragment. Previously, the amino acid sequence of eukaryotic (the brine shrimp Artemia franciscana) Hsp70 and DnaK proteins were shown to share a high degree of homology, particularly in the peptide-binding domain (59.6%, the putative innate immunity-activating portion) compared to the N-terminal ATPase (48.8%) and the C-terminal lid domains (19.4%). Next to this remarkable conservation, these proteins have been shown to generate protective immunity in Artemia against pathogenic Vibrio campbellii. This study, aimed to unravel the Vibrio-protective domain of Hsp70s in vivo, demonstrated that gnotobiotically cultured Artemia fed with recombinant C-terminal fragment (containing the conserved peptide binding domain) of Artemia Hsp70 or DnaK protein were well protected against subsequent Vibrio challenge. In addition, the prophenoloxidase (proPO) system, at both mRNA and protein activity levels, was also markedly induced by these truncated proteins, suggesting epitope(s) responsible for priming the proPO system and presumably other immune-related genes, consequently boosting Artemia survival upon challenge with V. campbellii, might be located within this conserved region of the peptide binding domain.

  17. Purification and partial characterization of thiol protease inhibitors from embryos of the brine shrimp Artemia.

    PubMed

    Warner, A H; Sonnenfeld-Karcz, M J

    1992-01-01

    Thiol protease inhibitor (TPI) proteins in embryos of the brine shrimp Artemia were purified to apparent homogeneity and several of their properties were studied. Four protein fractions containing thiol protease inhibitor activity were obtained by high performance liquid chromatography of Artemia embryo proteins on a C-18 reverse-phase column and these were designated as TPI-1a, -1b, -2, and -3. Acrylamide gel electrophoresis showed that TPI-1a and TPI-1b each consisted of two bands of 11.8 and 13.6 kilodaltons (kDa), while TPI-2 and TPI-3 consisted of only one band of 12.5 kDa. Isoelectric focusing experiments demonstrated that TPI-3 contained one band at pH 5.3, while both TPI-1b and TPI-2 yielded bands at pH 5.2 and 5.3. TPI-1a did not yield any major bands. Amino acid composition analyses of the Artemia TPI proteins showed them to be remarkably similar to one another. All were rich in valine and aspartic and glutamic acids, and devoid of cysteine. Partial trypsin digestion of TPI-1b, TPI-2, and TPI-3 yielded several peptides with identical mobilities on a reverse-phase column and several other peptides with different mobilities, suggesting that the multiple forms of Artemia TPIs may have originated from the same parental protein. N-terminal amino acid sequence analyses of TPI-3 suggest that Artemia TPI proteins are members of the type I cystatin family of protease inhibitors.

  18. Heterologous gene expression driven by carbonic anhydrase gene promoter in Dunaliella salina

    NASA Astrophysics Data System (ADS)

    Yurong, Chai; Yumin, Lu; Tianyun, Wang; Weihong, Hou; Lexun, Xue

    2006-12-01

    Dunaliella salina, a halotolerant unicellular green alga without a rigid cell wall, can live in salinities ranging from 0.05 to 5 mol/L NaCl. These features of D. salina make it an ideal host for the production of antibodies, oral vaccine, and commercially valuable polypeptides. To produce high level of heterologous proteins from D. salina, highly efficient promoters are required to drive expression of target genes under controlled condition. In the present study, we cloned a 5' franking region of 1.4 kb from the carbonic anhydrase ( CAH) gene of D. salina by genomic walking and PCR. The fragment was ligated to the pMD18-T vector and characterized. Sequence analysis indicated that this region contained conserved motifs, including a TATA- like box and CAAT-box. Tandem (GT)n repeats that had a potential role of transcriptional control, were also found in this region. The transcription start site (TSS) of the CAH gene was determined by 5' RACE and nested PCR method. Transformation assays showed that the 1.4 kb fragment was able to drive expression of the selectable bar (bialaphos resistance) gene when the fusion was transformed into D. salina by biolistics. Northern blotting hybridizations showed that the bar transcript was most abundant in cells grown in 2 mol/L NaCl, and less abundant in 0.5 mol/L NaCl, indicating that expression of the bar gene was induced at high salinity. These results suggest the potential use of the CAH gene promoter to induce the expression of heterologous genes in D. salina under varied salt condition.

  19. Phytochelatin synthesis in Dunaliella salina induced by arsenite and arsenate under various phosphate regimes.

    PubMed

    Wang, Ya; Zhang, Chunhua; Zheng, Yanheng; Ge, Ying

    2017-02-01

    This study investigated the dynamic variations in thiol compounds, including cysteine (Cys), glutathione (GSH), and phytochelatins (PCs), in Dunaliella salina samples exposed to arsenite [As(III)] and arsenate [As(V)] under various phosphate (PO4(3-)) regimes. Our results showed that GSH was the major non-protein sulfhydryl compound in D. salina cells. As(III) and As(V) induced PC syntheses in D. salina. PC2, PC3, and PC4 were all found in algal cells; the PC concentrations decreased gradually while exposed to As for 3 d. The synthesis of PC2-3 was significantly affected by As(III) and As(V) concentrations in the cultures. More PCs were detected in the As(V)-treated algal cells compared with the As(III) treatment. PC levels increased with As(III)/As(V) amount in the medium, but remained stable after 112μgL(-1) As(V) exposure. In contrast, significant (p<0.001) positive correlations were observed between PC synthesis and intracellular As(III) content or As accumulation in As(III)-treated algal cells during the 72-h exposure. PO4(3-) had a significant influence on the PC synthesis in algal cells, irrespective of the As-treated species. Reductions in As uptake and subsequent PC synthesis by D. salina were observed as the PO4(3-) concentration in the growth medium increased. L-Buthionine sulfoximine (BSO) differentially influenced PC synthesis in As-treated D. salina under different extracellular PO4(3-) regimes. Overall, our data demonstrated that the production of GSH and PCs was affected by PO4(3-) and that these thiols played an important role in As detoxification by D. salina.

  20. Pseudomonas salina sp. nov., isolated from a salt lake.

    PubMed

    Zhong, Zhi-Ping; Liu, Ying; Hou, Ting-Ting; Liu, Hong-Can; Zhou, Yu-Guang; Wang, Fang; Liu, Zhi-Pei

    2015-09-01

    A Gram-staining-negative, facultatively aerobic bacterium, strain XCD-X85(T), was isolated from Xiaochaidan Lake, a salt lake (salinity 9.9%, w/v) in Qaidam basin, Qinghai province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain XCD-X85(T) were non-endospore-forming rods, 0.4-0.6 μm wide and 1.0-1.6 μm long, and motile by means of a single polar flagellum. Strain XCD-X85(T) was catalase- and oxidase-positive. Growth was observed in the presence of 0-12.0% (w/v) NaCl (optimum, 1.0-2.0%) and at 4-35 °C (optimum, 25-30 °C) and pH 6.5-10.5 (optimum, pH 8.0-8.5). Strain XCD-X85(T) contained (>10%) summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the predominant fatty acids. The major respiratory quinone was ubiquinone 9 (Q-9). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 57.4 mol%. Phylogenetic trees based on 16S rRNA gene sequences showed that strain XCD-X85(T) was associated with the genus Pseudomonas, and showed highest 16S rRNA gene sequence similarities to Pseudomonas pelagia CL-AP6(T) (99.0%) and Pseudomonas bauzanensis BZ93(T) (96.8%). DNA-DNA relatedness of strain XCD-X85T to P. pelagia JCM 15562(T) was 19 ± 1%. On the basis of the data presented above, it is concluded that strain XCD-X85(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salina sp. nov. is proposed. The type strain is XCD-X85(T) ( = CGMCC 1.12482(T) = JCM 19469(T)).

  1. A biometric and ecologic comparison between Artemia from Mexico and Chile

    PubMed Central

    Castro, Thalía B; Gajardo, Gonzalo; Castro, Jorge M; Castro, Germán M

    2006-01-01

    Background A preliminary biometric and ecologic database for the brine shrimp Artemia from Mexico and Chile is presented. The area abounds in small and seasonal ponds and large inland lakes, the latter mainly located in Mexico, although relatively large and isolated lakes are found in complex hydrological settings in pre-high plateau areas of Chile. This paper summarizes research efforts aimed at the localization, characterization, and evaluation of the aquaculture potential of Artemia populations in Mexico and Chile, which exhibit great habitat diversity (ponds, salterns, coastal lagoons, sea arms, coastal and inland lakes), contrasting weather conditions and different levels of isolation and human intervention. Results This study covered locations between 29° north latitude (Baja California, Mexico) to 50° south latitude (Puerto Natales, Chile). Biological characteristics considered are species name, reproductive mode, cyst diameter, chorion thickness, and nauplius length, whereas ecological data include pond size, pH, salinity, temperature, and water ionic composition. Artemia franciscana is the only species found in Mexico, it exists together with A. persimilis in Chile, though separated geographically. Ecological differences in habitat exist between both regions but also within countries, a pattern particularly clear with regard to water composition. Surprisingly, a Mexican (Cuatro Ciénegas, A. franciscana) and a Chilean location (Torres del Paine, A. persimilis) share habitat characteristics, at least for the period when data were collected. The discriminat analysis for cyst diameter and nauplius length shows that Artemia from only one location match in cyst diameter with those from San Francisco Bay (SFB) (Point Lobos), and one (Marquez) is far apart from SFB and all the others. The Chilean locations (Pampilla, Cejar, Cahuil, Llamara, Yape) share cyst diameter, but tend to differ from SFB. The remaining Mexican locations (Juchitan, Ohuira, Yavaros) are

  2. Pesticide Risk Communication, Risk Perception, and Self-Protective Behaviors among Farmworkers in California's Salinas Valley

    ERIC Educational Resources Information Center

    Cabrera, Nolan L.; Leckie, James O.

    2009-01-01

    Agricultural pesticide use is the highest of any industry, yet there is little research evaluating farmworkers' understandings of the health risks chemical exposure poses. This study examines pesticide education, risk perception, and self-protective behaviors among farmworkers in California's Salinas Valley. Fifty current and former farmworkers…

  3. 76 FR 18547 - Grand River Dam Authority, Salina Pumped Storage Project; Notice of Proposed Restricted Service...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Grand River Dam Authority, Salina Pumped Storage Project; Notice of Proposed... Inclusion in the National Register of Historic Places Rule 2010 of the Federal Energy Regulatory...

  4. Antioxidant activity of three microalgae Dunaliella salina, Tetraselmis chuii and Isochrysis galbana clone Tahiti

    NASA Astrophysics Data System (ADS)

    Widowati, Ita; Zainuri, Muhammad; Pancasakti Kusumaningrum, Hermien; Susilowati, Ragil; Hardivillier, Yann; Leignel, Vincent; Bourgougnon, Nathalie; Mouget, Jean-Luc

    2017-02-01

    Natural alternatives antioxidant source has become a trending topic in the past decades to replace synthetic antioxidant. Microalgae have been mentioned to show interesting bioactive properties and one of them is its antioxidant activity. This study aims to evaluate the potential of three microalgae Dunaliella salina, Tetraselmis chuii and Isochrysis galbanaas new source of natural antioxidant. Proximate analysis and total phenolic content of D. salina, T. chuii and I. galbanas were determined. Antioxidant activity of methanolic extracts of these three species prepared in different concentration (50, 100, 250, 500, and 1000 ppm) was performed through DPPH assay. I. galbana clone Tahiti demonstrated a highest antioxidant potential with 61.64 of inhibition at 50 ppm followed by D. salina with 58.45 % of inhibition and T. chuii with 52.58 % of inhibition. I. galbana clone Tahiti was the best antioxidant with total phenol content of 17.798 mg GAE g-1 extract at 50 ppm; followed by T. chuii 16.868 mg GAE g-1 extract and the lowest was D. salina with 4.672 mg GAE g-1 extract. Results suggest that these microalgae posses antioxidant potential which could be considered for future applications in medicine, dietary supplements, cosmetics or food industries.

  5. Podosphaera xanthii but not Golovinomyces cichoracearum infects Cucurbits in a Greenhouse at Salinas, California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two fungal species are the primary causes of cucurbit powdery mildew (CPM): Podosphaera xanthii and Golovinomyces cichoracearum. CPM on melon (Cucumis melo L.), cucumber (C. sativus L.) and summer squash (Cucurbita pepo L.) in a greenhouse at Salinas, California in winter 2011 was confirmed to be in...

  6. Biochemical composition and bioactivity screening of various extracts from Dunaliella salina, a green microalga.

    PubMed

    Cakmak, Yavuz Selim; Kaya, Murat; Asan-Ozusaglam, Meltem

    2014-01-01

    The current study examines the antimicrobial and antioxidant properties of different extracts of the microalga Dunaliella salina Teodoresco (Dunaliellaceae), their fatty acid composition and the antimicrobial activity of the oil. Antimicrobial and antioxidant activities were evaluated by obtaining extracts of D. salina in n-hexane, dichloromethane, ethanol, and methanol. To evaluate the antimicrobial activity, the extracts, and fatty acids from D. salina were assessed by the disc diffusion and microdilution techniques against pathogenic microorganisms including fish and clinical/food-borne. The MBC or MFC values of the extracts and fatty acids ranged from 0.63 to 10.00 mg/ml. The antioxidant activity was studied by phosphomolybdenum and DPPH assays and ß-carotene/linoleic acid tests. In addition, the total phenolic and flavonoid contents were evaluated and the fatty acid composition was determined using gas chromatography. Palmitic, alpha-linolenic, and oleic acids were discovered to be the major components of the fatty acids. These findings have demonstrated that the extracts and oil from D. salina could be used as natural antimicrobials and antioxidants in the food/feed and pharmaceutical industry and as a biodiesel because of its high unsaturated fatty acid content.

  7. Inhibition of pds gene expression via the RNA interference approach in Dunaliella salina (Chlorophyta).

    PubMed

    Sun, Guohua; Zhang, Xuecheng; Sui, Zhenghong; Mao, Yunxiang

    2008-01-01

    To investigate the potential of double-stranded RNA interferencing with gene expression in Dunaliella salina, a plasmid pBIRNAI-Dsa was constructed to express hairpin RNA (hpRNA) containing sequences homologous to phytoene desaturase gene (pds), a key gene in carotenoid biosynthesis, and transformed into D. salina by electroporation. The relative transcription level of pds in pBIRNAI-Dsa-treated cells to nontreated cells was quantitated and the gene silencing efficiency by RNAi was evaluated via real-time polymerase chain reaction (PCR). The transcriptions of pds of the pBIRNAI-Dsa-treated group changed compared to those of the control group, and the 2(-delta deltaC)(T) was lowest on the 7th day, corresponding to 0.281265-fold of the relative pds control transcript; a relatively strong gene inhibition effect was therefore deduced. The transcript of pds may be modulated in a wide range, and a reduced transcription even to 28% of the normal level may be tolerated for its survival. This study shows that dsRNA-mediated genetic interference can induce sequence-specific inhibition of gene expression and pBIRNAI-Dsa can be used for transient suppression of gene expression in D. salina. The aim of this study was to exploit dsRNA-mediated gene silencing and to provide a foundation for gene function research in D. salina.

  8. U. S. EPA settlement requires Salinas, Calif. Realty company to remove lead-based paint

    EPA Pesticide Factsheets

    SAN FRANCISCO - The U.S. Environmental Protection Agency announced a settlement with Piini Realty, Inc. for failing to notify its tenants about the potential presence of lead-based paint at 12 rental units located in Salinas, Calif. As part of the s

  9. Hepatoprotective and Antioxidant Activity of Dunaliella salina in Paracetamol-induced Acute Toxicity in Rats.

    PubMed

    Madkour, Fedekar F; Abdel-Daim, M M

    2013-11-01

    Paracetamol has a reasonable safety profile when taken in therapeutic doses. However, it could induce hepatotoxicity and even more severe fatal acute hepatic damage when taken in an overdose. The green alga, Dunaliella salina was investigated for hepatoprotective and antioxidant activity against paracetamol-induced liver damage in rats. Male albino Wistar rats overdosed with paracetamol showed liver damage and oxidative stress as indicated by significantly (P<0.05) increased serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide. At the same time, there were decreased activities of serum superoxide dismutase and total antioxidant capacity compared with the control group. Treatment with D. salina methanol extract at doses of 500 and 1000 mg/kg body weight or silymarin could significantly (P<0.05) decrease the liver damage marker enzymes, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide levels and increase the activities of superoxide dismutase and total antioxidant capacity in serum when compared with paracetamol intoxicated group. Liver histopathology also showed that D. salina reduced the centrilobular necrosis, congestion and inflammatory cell infiltration evoked by paracetamol overdose. These results suggest that D. salina exhibits a potent hepatoprotective effect on paracetamol-induced liver damage in rats, which may be due to both the increase of antioxidant enzymes activity and inhibition of lipid peroxidation.

  10. Biochemical composition and bioactivity screening of various extracts from Dunaliella salina, a green microalga

    PubMed Central

    Cakmak, Yavuz Selim; Kaya, Murat; Asan-Ozusaglam, Meltem

    2014-01-01

    The current study examines the antimicrobial and antioxidant properties of different extracts of the microalga Dunaliella salina Teodoresco (Dunaliellaceae), their fatty acid composition and the antimicrobial activity of the oil. Antimicrobial and antioxidant activities were evaluated by obtaining extracts of D. salina in n-hexane, dichloromethane, ethanol, and methanol. To evaluate the antimicrobial activity, the extracts, and fatty acids from D. salina were assessed by the disc diffusion and microdilution techniques against pathogenic microorganisms including fish and clinical/food-borne. The MBC or MFC values of the extracts and fatty acids ranged from 0.63 to 10.00 mg/ml. The antioxidant activity was studied by phosphomolybdenum and DPPH assays and ß-carotene/linoleic acid tests. In addition, the total phenolic and flavonoid contents were evaluated and the fatty acid composition was determined using gas chromatography. Palmitic, alpha-linolenic, and oleic acids were discovered to be the major components of the fatty acids. These findings have demonstrated that the extracts and oil from D. salina could be used as natural antimicrobials and antioxidants in the food/feed and pharmaceutical industry and as a biodiesel because of its high unsaturated fatty acid content. PMID:26417292

  11. Hepatoprotective and Antioxidant Activity of Dunaliella salina in Paracetamol-induced Acute Toxicity in Rats

    PubMed Central

    Madkour, Fedekar F.; Abdel-Daim, M. M.

    2013-01-01

    Paracetamol has a reasonable safety profile when taken in therapeutic doses. However, it could induce hepatotoxicity and even more severe fatal acute hepatic damage when taken in an overdose. The green alga, Dunaliella salina was investigated for hepatoprotective and antioxidant activity against paracetamol-induced liver damage in rats. Male albino Wistar rats overdosed with paracetamol showed liver damage and oxidative stress as indicated by significantly (P<0.05) increased serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide. At the same time, there were decreased activities of serum superoxide dismutase and total antioxidant capacity compared with the control group. Treatment with D. salina methanol extract at doses of 500 and 1000 mg/kg body weight or silymarin could significantly (P<0.05) decrease the liver damage marker enzymes, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide levels and increase the activities of superoxide dismutase and total antioxidant capacity in serum when compared with paracetamol intoxicated group. Liver histopathology also showed that D. salina reduced the centrilobular necrosis, congestion and inflammatory cell infiltration evoked by paracetamol overdose. These results suggest that D. salina exhibits a potent hepatoprotective effect on paracetamol-induced liver damage in rats, which may be due to both the increase of antioxidant enzymes activity and inhibition of lipid peroxidation. PMID:24591738

  12. Two-dimensional and three-dimensional digital flow models of the Salinas Valley ground-water basin, California

    USGS Publications Warehouse

    Durbin, T.J.; Kapple, G.W.; Freckleton, J.R.

    1978-01-01

    The Salinas Valley ground-water basin is in central coastal California. The ground-water basin extends from Monterey Bay southeastward along the Salinas River to San Ardo, a distance of about 70 miles, and has a maximum thickness of about 2,000 feet. Annual recharge to the ground-water basin, which is derived mostly from the Salinas River, is about 290,000 acre-feet. Annual discharge, which is mostly from pumpage but also includes the consumptive use of ground water by riparian vegetation along the Salinas River, is about 507,000 acre-feet. About 45 percent of the pumpage, or about 217,000 acre-feet of water annually, returns to the ground-water system. A system of interacting hydrologic models was developed for the Salinas Valley. These models include the small-stream model, river model, two-dimensional ground-water model, and three-dimensional ground-water model. The small-stream model simulates ground-water recharge from small streams that are tributary to the Salinas River. The river model simulates ground-water recharge from the surface-water discharge in the Salinas River. The two-dimensional and three-dimensional ground-water models simulate hydraulic head in the ground-water basin. (Woodard-USGS)

  13. Groundwater quality in the Monterey Bay and Salinas Valley groundwater basins, California

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2011-01-01

    The Monterey-Salinas study unit is nearly 1,000 square miles and consists of the Santa Cruz Purisima Formation Highlands, Felton Area, Scotts Valley, Soquel Valley, West Santa Cruz Terrace, Salinas Valley, Pajaro Valley, and Carmel Valley groundwater basins (California Department of Water Resources, 2003; Kulongski and Belitz, 2011). These basins were grouped into four study areas based primarily on geography. Groundwater basins in the north were grouped into the Santa Cruz study area, and those to the south were grouped into the Monterey Bay, the Salinas Valley, and the Paso Robles study areas (Kulongoski and others, 2007). The study unit has warm, dry summers and cool, moist winters. Average annual rainfall ranges from 31 inches in Santa Cruz in the north to 13 inches in Paso Robles in the south. The study areas are drained by several rivers and their principal tributaries: the Salinas, Pajaro, and Carmel Rivers, and San Lorenzo Creek. The Salinas Valley is a large intermontane valley that extends southeastward from Monterey Bay to Paso Robles. It has been filled, up to a thickness of 2,000 feet, with Tertiary and Quaternary marine and terrestrial sediments that overlie granitic basement. The Miocene-age Monterey Formation and Pliocene- to Pleistocene-age Paso Robles Formation, and Pleistocene to Holocene-age alluvium contain freshwater used for supply. The primary aquifers in the study unit are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 650 feet, consist of solid casing from the land surface to depths of about 175 to 500 feet, and are perforated below the solid casing. Water quality in the primary aquifers may differ from that in the shallower and deeper parts of the aquifer system. Groundwater movement is generally from the southern part of the Salinas Valley north towards the Monterey Bay

  14. Ghrelin in Senegalese sole (Solea senegalensis) post-larvae: Paracrine effects on food intake.

    PubMed

    Navarro-Guillén, Carmen; Yúfera, Manuel; Engrola, Sofia

    2017-02-01

    Successful food consumption and digestion depend on specifics anatomical and behavioral characteristics and corresponding physiological functions that should be ready to work at the appropriate time. The physiological regulation of appetite and ingestion involves a complex integration of peripheral and central signals by the brain. Ghrelin is a peptide hormone involved in the control of energy homeostasis and increases food intake in mammals, however ghrelin has species-specific actions on food intake in fish. The aim of this study was to investigate whether this peptide has an orexigenic or anorexigenic role in Senegalese sole (Solea senegalensis) in order to improve the knowledge of the physiological basis underlying feeding activity. Feed intake was measured at several sampling points to determine the overall action time of the peptide and its effect in Senegalese sole food intake. Artemia protein digestibility and retention were determined in order to analyze the ghrelin effect in fed and fasted Senegalese sole post-larvae. Results suggested that ghrelin acts as orexigenic hormone in Senegalese sole, with a response time around 25min. Results indicated that Senegalese sole post-larvae are able to maintain absorption and retention capacities independently of feeding rate and nutritional status. Furthermore, the present study gives insight for the first time of the fate of the retained amino acids, being mainly used for protein accretion (86.79% of retained amino acids recovered in protein and FAA fractions).

  15. The transcription factor p8 regulates autophagy during diapause embryo formation in Artemia parthenogenetica.

    PubMed

    Lin, Cheng; Jia, Sheng-Nan; Yang, Fan; Jia, Wen-Huan; Yu, Xiao-Jian; Yang, Jin-Shu; Yang, Wei-Jun

    2016-07-01

    Autophagy is an essential homeostatic process by which cytoplasmic components, including macromolecules and organelles, are degraded by lysosome. Increasing evidence suggests that phosphorylated AMP-activated protein kinase (p-AMPK) and target of rapamycin (TOR) play key roles in the regulation of autophagy. However, the regulation of autophagy in quiescent cells remains unclear, despite the fact that autophagy is known to be critical for normal development, regeneration, and degenerative diseases. Here, crustacean Artemia parthenogenetica was used as a model system because they produced and released encysted embryos that enter a state of obligate dormancy in cell quiescence to withstand various environmental threats. We observed that autophagy was increased before diapause stage but dropped to extremely low level in diapause cysts in Artemia. Western blot analyses indicated that the regulation of autophagy was AMPK/TOR independent during diapause embryo formation. Importantly, the level of p8 (Ar-p8), a stress-inducible transcription cofactor, was elevated at the stage just before diapause and was absent in encysted embryos, indicating that Ar-p8 may regulate autophagy. The results of Ar-p8 knockdown revealed that Ar-p8 regulated autophagy during diapause formation in Artemia. Moreover, we observed that activating transcription factors 4 and 6 (ATF4 and ATF6) responded to Ar-p8-regulated autophagy, indicating that autophagy targeted endoplasmic reticulum (ER) during diapause formation in Artemia. Additionally, AMPK/TOR-independent autophagy was validated in human gastric cancer MKN45 cells overexpressing Ar-p8. The findings presented here may provide insights into the role of p8 in regulating autophagy in quiescent cells.

  16. Participation of metanauplii and juvenile individuals of Artemia parthenogenetica (Branchiopoda) in the circulation of avian cestodes.

    PubMed

    Redón, Stella; Amat, Francisco; Hontoria, Francisco; Vasileva, Gergana P; Nikolov, Pavel N; Georgiev, Boyko B

    2011-04-01

    Adult crustaceans of the genus Artemia (brine shrimps) are intermediate hosts in the life cycle of cestode species parasitic in aquatic birds as their definitive hosts. However, there are no data on the role of larval and juvenile brine shrimps in the transmission of avian helminth parasites. In order to examine the possible role of early developmental stages (nauplii, metanauplii and juveniles) of Artemia for the circulation of avian cestodes, the natural cestode infection in the population of Artemia parthenogenetica from La Mata Lagoon, Mediterranean coast of Spain, was studied. Metacestodes (cysticercoids) of four cestode species were recorded in adult brine shrimps: Flamingolepis liguloides and Flamingolepis flamingo (hymenolepidids parasitic in flamingos), Confluaria podicipina (a hymenolepidid species parasitic in grebes) and Eurycestus avoceti (a dilepidid species parasitic in avocets, stilts, plovers and, to a lesser extent, in flamingos). No cysticercoids were found in nauplii. Two species, F. liguloides and F. flamingo, were found in metanauplii and juvenile brine shrimps. Only 36.3% of the cysticercoids of F. liguloides occurred in adult brine shrimps; the remaining 63.7% were parasitic in metanauplii (39.6%) and juveniles (24.1%). Similarly, the metacestodes of F. flamingo were also distributed among various age groups: in adults (44.4% of cysticercoids), juveniles (27.8%) and metanauplii (27.8%). These results indicate that the early developmental stages of Artemia have an important role for the circulation of certain parasite species. No cysticercoids of C. podicipina and E. avoceti were recorded in larval and juvenile brine shrimps. The selective infestation of larval brine shrimps with flamingo parasites is probably associated with the feeding behaviour of definitive hosts, which are filtering predators; in contrast, grebes and waders pick brine shrimps individually one by one. The possible underlying mechanism for selective infestation of

  17. Behavioural fever in zebrafish larvae.

    PubMed

    Rey, Sonia; Moiche, Visila; Boltaña, Sebastian; Teles, Mariana; MacKenzie, Simon

    2017-02-01

    Behavioural fever has been reported in different species of mobile ectotherms including the zebrafish, Danio rerio, in response to exogenous pyrogens. In this study we report, to our knowledge for the first time, upon the ontogenic onset of behavioural fever in zebrafish (Danio rerio) larvae. For this, zebrafish larvae (from first feeding to juveniles) were placed in a continuous thermal gradient providing the opportunity to select their preferred temperature. The novel thermal preference aquarium was based upon a continuous vertical column system and allows for non-invasive observation of larvae vertical distribution under isothermal (TR at 28 °C) and thermal gradient conditions (TCH: 28-32 °C). Larval thermal preference was assessed under both conditions with or without an immersion challenge, in order to detect the onset of the behavioural fever response. Our results defined the onset of the dsRNA induced behavioural fever at 18-20 days post fertilization (dpf). Significant differences were observed in dsRNA challenged larvae, which prefer higher temperatures (1-4 °C increase) throughout the experimental period as compared to non-challenged larvae. In parallel we measured the abundance of antiviral transcripts; viperin, gig2, irf7, trim25 and Mxb mRNAs in dsRNA challenged larvae under both thermal regimes: TR and TCh. Significant increases in the abundance of all measured transcripts were recorded under thermal choice conditions signifying that thermo-coupling and the resultant enhancement of the immune response to dsRNA challenge occurs from 18 dpf onwards in the zebrafish. The results are of importance as they identify a key developmental stage where the neuro-immune interface matures in the zebrafish likely providing increased resistance to viral infection.

  18. Laboratory generation of new parthenogenetic lineages supports contagious parthenogenesis in Artemia.

    PubMed

    Maccari, Marta; Amat, Francisco; Hontoria, Francisco; Gómez, Africa

    2014-01-01

    Contagious parthenogenesis-a process involving rare functional males produced by a parthenogenetic lineage which mate with coexisting sexual females resulting in fertile parthenogenetic offspring-is one of the most striking mechanisms responsible for the generation of new parthenogenetic lineages. Populations of the parthenogenetic diploid brine shrimp Artemia produce fully functional males in low proportions. The evolutionary role of these so-called Artemia rare males is, however, unknown. Here we investigate whether new parthenogenetic clones could be obtained in the laboratory by mating these rare males with sexual females. We assessed the survival and sex ratio of the hybrid ovoviviparous offspring from previous crosses between rare males and females from all Asiatic sexual species, carried out cross-mating experiments between F1 hybrid individuals to assess their fertility, and estimated the viability and the reproductive mode of the resulting F2 offspring. Molecular analysis confirmed the parentage of hybrid parthenogenetic F2. Our study documents the first laboratory synthesis of new parthenogenetic lineages in Artemia and supports a model for the contagious spread of parthenogenesis. Our results suggest recessive inheritance but further experiments are required to confirm the likelihood of the contagious parthenogenesis model.

  19. Laboratory generation of new parthenogenetic lineages supports contagious parthenogenesis in Artemia

    PubMed Central

    Amat, Francisco; Hontoria, Francisco; Gómez, Africa

    2014-01-01

    Contagious parthenogenesis—a process involving rare functional males produced by a parthenogenetic lineage which mate with coexisting sexual females resulting in fertile parthenogenetic offspring—is one of the most striking mechanisms responsible for the generation of new parthenogenetic lineages. Populations of the parthenogenetic diploid brine shrimp Artemia produce fully functional males in low proportions. The evolutionary role of these so-called Artemia rare males is, however, unknown. Here we investigate whether new parthenogenetic clones could be obtained in the laboratory by mating these rare males with sexual females. We assessed the survival and sex ratio of the hybrid ovoviviparous offspring from previous crosses between rare males and females from all Asiatic sexual species, carried out cross-mating experiments between F1 hybrid individuals to assess their fertility, and estimated the viability and the reproductive mode of the resulting F2 offspring. Molecular analysis confirmed the parentage of hybrid parthenogenetic F2. Our study documents the first laboratory synthesis of new parthenogenetic lineages in Artemia and supports a model for the contagious spread of parthenogenesis. Our results suggest recessive inheritance but further experiments are required to confirm the likelihood of the contagious parthenogenesis model. PMID:25024909

  20. The study of fkbp and ubiquitin reveals interesting aspects of Artemia stress history.

    PubMed

    Maniatsi, Stefania; Farmaki, Theodora; Abatzopoulos, Theodore J

    2015-08-01

    Research on stress responses in animals has increased greatly during the last decades. Though most studies focus on the cellular and molecular bases of the stress response mechanisms, the ecological and evolutionary aspects of stress responses gain more and more interest. Here, we use species and parthenogenetic strains of the genus Artemia, an extremophile model organism, to study, for the first time, a protein well known for its chaperone activity and its involvement in stress responses. More specifically, transcription and protein accumulation of an FK506-Binding Protein (FKBP) homologue were investigated under heat and salt stresses. Additionally, the mRNA levels of ubiquitin, a heat-inducible protein related to the proteasomal pathway, were quantitated under these conditions. Biochemical and phylogenetic analyses showed that the studied FKBP orthologue is a typical representative of the family that clusters with other crustacean sequences. The expression was increased in both fkbp and ubiquitin genes after salt and heat stresses. However, our results in combination with the fact that Artemia species and parthenogenetic strains, selected for this study, exhibit different heat or salt tolerance provide useful hints about the evolutionary significance of FKBP and ubiquitin. Regarding FKBP, mRNA expression and protein accumulation seem to depend on the environmental conditions and the evolutionary history of each Artemia population while ubiquitin has a clear and more conserved role under heat shock.

  1. Mechanisms associated with cellular desiccation tolerance of Artemia encysted embryos from locations around the world.

    PubMed

    Hengherr, Steffen; Schill, Ralph O; Clegg, J S

    2011-10-01

    Using differential scanning calorimetry we demonstrated the presence of biological glasses and measured the glass transition temperatures (Tg) in dry encysted gastrula embryos (cysts) of the brine shrimp, Artemia, from eleven different locations, two of which provided cysts from parthenogenetic animals. Values for Tg were highest, by far, in Artemia franciscana cysts from the Mekong Delta, Vietnam (VN), these cysts having been produced from previous sequential inoculations into growth ponds of cysts from the San Francisco Bay, California, USA. Tg values for three groups of A. franciscana cysts were significantly higher than those of other cysts (except those of Artemia persimilis) studied here, as well as all other desiccation-tolerant animal systems studied to date. We also measured three stress proteins (hsc70, artemin and p26) in all these cysts as well as the total alcohol soluble carbohydrates (ASC), about 90% of which is the disaccharide trehalose, a known component of biological glasses. We interpret the results in terms of mechanisms involved with desiccation tolerance and, to some extent, with thermal conditions at the sites of cyst collection.

  2. Regulation of trehalase expression inhibits apoptosis in diapause cysts of Artemia.

    PubMed

    Yang, Fan; Chen, Su; Dai, Zhong-Min; Chen, Dian-Fu; Duan, Ru-Bing; Wang, Hong-Liang; Jia, Sheng-Nan; Yang, Wei-Jun

    2013-12-01

    Trehalase, which specifically hydrolyses trehalose into glucose, plays an important role in the metabolism of trehalose. Large amounts of trehalose are stored in the diapause encysted embryos (cysts) of Artemia, which are not only vital to their extraordinary stress resistance, but also provide a source of energy for development after diapause is terminated. In the present study, a mechanism for the transcriptional regulation of trehalase was described in Artemia parthenogenetica. A trehalase-associated protein (ArTAP) was identified in Artemia-producing diapause cysts. ArTAP was found to be expressed only in diapause-destined embryos. Further analyses revealed that ArTAP can bind to a specific intronic segment of a trehalase gene. Knockdown of ArTAP by RNAi resulted in the release of cysts with coarse shells in which two chitin-binding proteins were missing. Western blotting showed that the level of trehalase was increased and apoptosis was induced in these ArTAP-knockdown cysts compared with controls. Taken together, these results show that ArTAP is a key regulator of trehalase expression which, in turn, plays an important role in trehalose metabolism during the formation of diapause cysts.

  3. Essential oils of Nigella sativa protects Artemia from the pathogenic effect of Vibrio parahaemolyticus Dahv2.

    PubMed

    Manju, Sivalingam; Malaikozhundan, Balasubramanian; Withyachumnarnkul, Boonsirm; Vaseeharan, Baskaralingam

    2016-05-01

    The anti-Vibrio activity of essential oils (EOs) of nine medicinal plants was tested against 28 Vibrio spp. isolated from diseased Fenneropenaeus indicus. EO of Nigella sativa exhibited anti-Vibrio activity against all Vibrio spp. and greater inhibition was noted for the isolate V2 which was identified as Vibrio parahaemolyticus Dahv2. Further, EO of N. sativa effectively inhibited V. parahaemolyticus Dahv2 with an inhibition zone of 23.9mm at 101.2μgml(-1). Moreover, EO of N. sativa revealed anti-biofilm activity at 101.2μgml(-1) against V. parahaemolyticus Dahv2 and inhibited the growth of V. parahaemolyticus Dahv2 at 100μgml(-1).In vivo experimental infection studies showed that the survival of Artemia spp. infected with V. parahaemolyticus Dahv2 at 1×10(3)cfuml(-1) was only 40%. However, the survival of Artemia spp. was significantly increased after challenge with 100μgml(-1) of EO of N. sativa. EO of N. sativa showed higher anti-oxidant potential and total phenol content than other EOs tested. The anti-oxidant activity of EO of N. sativa was highly correlated to their total phenolic contents (r=0.836, P<0.05). This observation suggests that EO of N. sativa protected the Artemia spp. after experimental infection of V. parahaemolyticus Dahv2.

  4. Surfactant toxicity to Artemia Franciscana and the influence of humic acid and chemical composition

    PubMed Central

    Deese, Rachel D.; LeBlanc, Madeline R.

    2016-01-01

    Surfactants can be extremely toxic to aquatic species and are introduced to the environment in a variety of ways. It is thus important to understand how other environmental constituents, in this case humic acids (HAs), may alter the toxicity of anthropogenic surfactants. Hatching and mortality assays of Artemia Franciscana were performed for three different toxic surfactants: Triton X-100 (Tx-100, non-ionic), cetylpyridinium chloride (CPC, cationic), and sodium dodecyl sulfate (SDS, anionic). Humic acids of varying composition and concentrations were added to the assays to determine the toxicity mitigating ability of the HAs. Tx-100 had a significant toxic effect on Artemia mortality rates and HAs from terrestrial sources were able to mitigate the toxicity, but an aquatic HA did not. CPC and SDS limited hatching success of the Artemia and, as HAs were added, the hatching percentages increased for all HA sources, indicating toxicity mitigation. In order to determine which functional groups within HAs were responsible for the interaction with the surfactants, the HAs were chemically modified by: (i) bleaching to reduce aromatics, (ii) Soxhlet extraction to reduce lipids, and (iii) acid hydrolysis to reduce O- and N-alkyl groups. Although most of the modified HAs had some toxicity mitigating ability for each of the surfactants, there were two notable differences: 1) the lipid-extracted HA did not reduce the toxicity of Tx-100 and 2) the bleached HA had a lower toxicity mitigating ability for CPC than the other modified HAs. PMID:27453688

  5. La columna, el circulo y sus variantes en la poesia primera de Pedro Salinas (The Vertical Line, the Circle, and other Geometric Varieties in the Early Poetry of Pedro Salinas)

    ERIC Educational Resources Information Center

    De Armas, Jose R.

    1970-01-01

    Interprets Salinas' use of geometric figures for depicting concepts of time and infinity, and for portraying idealism and realism (the vertical line is idealism, perfection; the circle stands for reality and imperfection). (DS)

  6. Skeletal muscle growth dynamics and the influence of first-feeding diet in Atlantic cod larvae (Gadus morhua L.).

    PubMed

    Vo, Tu A; Galloway, Trina F; Bardal, Tora; Halseth, Christine K; Øie, Gunvor; Kjørsvik, Elin

    2016-11-15

    Dynamics between hypertrophy (increase in cell size) and hyperplasia (increase in cell numbers) of white and red muscle in relation to body size [standard length (SL)], and the influence of the first-feeding diets on muscle growth were investigated in Atlantic cod larvae (Gadus morhua). Cod larvae were fed copepod nauplii or rotifers of different nutritional qualities from 4 to 29 days post hatching (dph), Artemia nauplii from 20 to 40 dph and a formulated diet from 36 to 60 dph. The short period of feeding with cultivated copepod nauplii had a positive effect on both muscle hyperplasia and hypertrophy after the copepod/rotifer phase (19 dph), and a positive long term effect on muscle hypertrophy (60 dph). The different nutritional qualities of rotifers did not significantly affect muscle growth. We suggest here a model of the dynamics between hyperplasia and hypertrophy of red and white muscle fibre cells in relation to cod SL (4 to 30 mm), where the different red and white muscle growth phases clearly coincided with different metamorphosis stages in cod larvae. These shifts could be included as biomarkers for the different stages of development during metamorphosis. The main dietary muscle effect was that hypertrophic growth of red muscle fibres was stronger in cod larvae that were fed copepods than in larvae that were fed rotifers, both in relation to larval age and size. Red muscle fibres are directly involved in larval locomotory performance, but may also play an important role in the larval myogenesis. This can have a long term effect on growth potential and fish performance.

  7. Skeletal muscle growth dynamics and the influence of first-feeding diet in Atlantic cod larvae (Gadus morhua L.)

    PubMed Central

    Vo, Tu A.; Galloway, Trina F.; Bardal, Tora; Halseth, Christine K.; Øie, Gunvor

    2016-01-01

    ABSTRACT Dynamics between hypertrophy (increase in cell size) and hyperplasia (increase in cell numbers) of white and red muscle in relation to body size [standard length (SL)], and the influence of the first-feeding diets on muscle growth were investigated in Atlantic cod larvae (Gadus morhua). Cod larvae were fed copepod nauplii or rotifers of different nutritional qualities from 4 to 29 days post hatching (dph), Artemia nauplii from 20 to 40 dph and a formulated diet from 36 to 60 dph. The short period of feeding with cultivated copepod nauplii had a positive effect on both muscle hyperplasia and hypertrophy after the copepod/rotifer phase (19 dph), and a positive long term effect on muscle hypertrophy (60 dph). The different nutritional qualities of rotifers did not significantly affect muscle growth. We suggest here a model of the dynamics between hyperplasia and hypertrophy of red and white muscle fibre cells in relation to cod SL (4 to 30 mm), where the different red and white muscle growth phases clearly coincided with different metamorphosis stages in cod larvae. These shifts could be included as biomarkers for the different stages of development during metamorphosis. The main dietary muscle effect was that hypertrophic growth of red muscle fibres was stronger in cod larvae that were fed copepods than in larvae that were fed rotifers, both in relation to larval age and size. Red muscle fibres are directly involved in larval locomotory performance, but may also play an important role in the larval myogenesis. This can have a long term effect on growth potential and fish performance. PMID:27612513

  8. Sediment bioassays with oyster larvae

    SciTech Connect

    Chapman, P.M.; Morgan, J.D.

    1983-10-01

    Tests with naturally-occurring sediments are rare and sediment testing methodology is not standardized. The authors present a simple methodology for undertaking sediment bioassays with oyster larvae, and present data from a recent study to prove the utility of this method.

  9. Arsenate toxicity and metabolism in the halotolerant microalga Dunaliella salina under various phosphate regimes.

    PubMed

    Wang, Ya; Zheng, Yanheng; Liu, Cong; Xu, Pingping; Li, Hao; Lin, Qiaoyun; Zhang, Chunhua; Ge, Ying

    2016-06-15

    Microalgae play an important role in arsenic (As) biogeochemical cycles as they are capable of accumulating and metabolizing this metalloid efficiently. This study aimed to investigate the toxicity, accumulation and transformation of arsenate (As(v)) in Dunaliella salina, an exceptionally halotolerant microalga, under various phosphate (PO4(3-)) regimes. The results of the 72-h toxicity test showed that D. salina was tolerant to As(v). In addition, the toxicity of As(v) was mitigated by an increased PO4(3-) supply. D. salina resisted the adverse effects of As(v) through the suppression of As uptake, enhancement of As reduction, methylation in the cell and excretion from the cell. Our study revealed that D. salina reduced As(v) toxicity using different strategies, i.e., reduction of As uptake upon acute As stress (24 h) and increase of As efflux following chronic As exposure (9 day). Moreover, PO4(3-) strongly affected the adsorption, uptake and transformation of As(v) in D. salina. As(v) reduction, DMA production and As excretion were enhanced under P-limited conditions (0.112 mg L(-1)) or upon higher As(v) exposure (1120 μg L(-1)). Furthermore, PO4(3-) had a significant influence on the As removal ability of D. salina. A high As removal efficiency (>95.6%) was observed in the 5-day cultures at an initial As concentration of 11.2 μg L(-1) and PO4(3-) of 0.112 and 1.12 mg L(-1). However, only 10.9% of total As was removed under 11.2 mg L(-1) PO4(3-) after 9 days of incubation. The findings of this study illustrate the pivotal roles of extracellular PO4(3-) in As(v) toxicity and metabolism, and the results may be relevant for future research on the minimization of As contamination in algal products as well as on the enhancement of As removal from the environment.

  10. How the pilidium larva feeds

    PubMed Central

    2013-01-01

    Introduction The nemertean pilidium is a long-lived feeding larva unique to the life cycle of a single monophyletic group, the Pilidiophora, which is characterized by this innovation. That the pilidium feeds on small planktonic unicells seems clear; how it does so is unknown and not readily inferred, because it shares little morphological similarity with other planktotrophic larvae. Results Using high-speed video of trapped lab-reared pilidia of Micrura alaskensis, we documented a multi-stage feeding mechanism. First, the external ciliation of the pilidium creates a swimming and feeding current which carries suspended prey past the primary ciliated band spanning the posterior margins of the larval body. Next, the larva detects prey that pass within reach, then conducts rapid and coordinated deformations of the larval body to re-direct passing cells and surrounding water into a vestibular space between the lappets, isolated from external currents but not quite inside the larva. Once a prey cell is thus captured, internal ciliary bands arranged within this vestibule prevent prey escape. Finally, captured cells are transported by currents within a buccal funnel toward the stomach entrance. Remarkably, we observed that the prey of choice – various cultured cryptomonads – attempt to escape their fate. Conclusions The feeding mechanism deployed by the pilidium larva coordinates local control of cilia-driven water transport with sensorimotor behavior, in a manner clearly distinct from any other well-studied larval feeding mechanisms. We hypothesize that the pilidium’s feeding strategy may be adapted to counter escape responses such as those deployed by cryptomonads, and speculate that similar needs may underlie convergences among disparate planktotrophic larval forms. PMID:23927417

  11. Can the halophilic ciliate Fabrea salina be used as a bio-control of microalgae blooms in solar salterns?

    NASA Astrophysics Data System (ADS)

    Hong, Hyun Pyo; Choi, Joong Ki

    2015-09-01

    The microlage Dunaliella salina, a major producer in salterns, is a serious problem for salt production. In this study we tried to assess if Fabrea salina can control D. salina. By parameterising numerical and functional response (growth and grazing vs prey abundance, respectively) at 90 psu and 30°C, where the ciliate is abundant and grows well, we developed a predator-prey model. The model is used to explore how change in microalga growth rate affect the dynamics, and the functional response is used in combination with field data to assess the potential impact of F. salina on D. salina. Over the 20 d simulation the ciliate controlled the prey population under all prey growth rates; although once D. salina were exhausted below the threshold level, F. salina died due to starvation, allowing the alga to increase in abundance, resulting in one or two predatorprey cycle, depending on prey growth rate. In general, the model predicted trends observed by others in the field, suggesting that it provided a good prediction of what may occur under the conditions we examined. Likewise we show that the ciliate can have a high impact on microalgal populations in the field. Finally, a literature review indicated that F. salina could be a good competitor with other protozoa and metazoan in salterns, depending on salinity and temperature, which requires further study and attention. In summary, we encourage continued studies on this unique ciliate on solar salterns and suggest that it may be useful in the bio-control of micoalgae.

  12. Efficacy of heterologous and homologous heat shock protein 70s as protective agents to Artemia franciscana challenged with Vibrio campbellii.

    PubMed

    Baruah, Kartik; Ranjan, Jayant; Sorgeloos, Patrick; Bossier, Peter

    2010-11-01

    The Hsp70 class of heat shock proteins (Hsps) has been implicated at multiple points in the immune response of both vertebrates and invertebrates. This class of chaperones is highly conserved in both sequence and structure, from prokaryotes to higher eukaryotes. In view of their high degree of homology, it was assumed that these Hsp70 proteins derived either from the prokaryotes or eukaryotes would have similar functions, especially in relation to their protective ability in a challenge assay. To verify this, we compared two evolutionary diverse Hsp70s, Artemia Hsp70 and Escherichia coli Hsp70 equivalent DnaK (each overproduced in E.coli), for their ability to protect Artemia against Vibrio challenge. Results showed that Artemia fed with E. coli producing Artemia Hsp70 or DnaK proteins, as assessed by immune-probing in western blots, survived better in a Vibrio challenge assay. The observed effects could be due to enhancement of the Artemia immune system as phenoloxidase activity was found to be increased by these proteins. These two Hsp70 proteins exhibit a high degree of homology, particularly in the peptide-binding domain (the putative innate immunity-activating portion) with 59.6% identity, indicating that the observed protective capacity of homologous or heterologous Hsp70 proteins might reside within this peptide-binding domain.

  13. Workbook on the Identification of Mosquito Larvae.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; And Others

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

  14. Identification and characterization of a new strain of the unicellular green alga Dunaliella salina (Teod.) from Korea.

    PubMed

    Polle, Jurgen E W; Struwe, Lena; Jin, Eonseon

    2008-05-01

    The unicellular green alga Dunaliella salina is a halotolerant eukaryotic organism. Its halophytic properties provide an important advantage for open pond mass cultivation, since D. salina can be grown selectively. D. salina was originally described by E. C. Teodoresco in 1905. Since that time, numerous isolates of D. salina have been identified from hypersaline environments on different continents. The new Dunaliella strain used for this study was isolated from the salt farm area of the west coastal side of South Korea. Cells of the new strain were approximately oval- or pear-shaped (approximately 16-24 microm long and 10-15 microm wide), and contained one pyrenoid, cytoplasmatic granules, and no visible eyespot. Although levels of beta-carotene per cell were relatively low in cells grown at salinities between 0.5 to 2.5 M NaCl, cells grown at 4.5 M NaCl contained about a ten-fold increase in cellular levels of beta-carotene, which demonstrated that cells of the new Korean strain of Dunaliella can overaccumulate beta- carotene in response to salt stress. Analysis of the ITS1 and ITS2 regions of the new Korean isolate showed that it is in the same clade as D. salina. Consequently, based on comparative cell morphology, biochemistry, and molecular phylogeny, the new Dunaliella isolate from South Korea was classified as D. salina KCTC10654BP.

  15. Monitoring of Vibrio harveyi quorum sensing activity in real time during infection of brine shrimp larvae.

    PubMed

    Defoirdt, Tom; Sorgeloos, Patrick

    2012-12-01

    Quorum sensing, bacterial cell-to-cell communication, has been linked to the virulence of pathogenic bacteria. Indeed, in vitro experiments have shown that many bacterial pathogens regulate the expression of virulence genes by this cell-to-cell communication process. Moreover, signal molecules have been detected in samples retrieved from infected hosts and quorum sensing disruption has been reported to result in reduced virulence in different host-pathogen systems. However, data on in vivo quorum sensing activity of pathogens during infection of a host are currently lacking. We previously reported that quorum sensing regulates the virulence of Vibrio harveyi in a standardised model system with gnotobiotic brine shrimp (Artemia franciscana) larvae. Here, we monitored quorum sensing activity in Vibrio harveyi during infection of the shrimp, using bioluminescence as a read-out. We found that wild-type Vibrio harveyi shows a strong increase in quorum sensing activity early during infection. In this respect, the bacteria behave remarkably similar in different larvae, despite the fact that only half of them survive the infection. Interestingly, when expressed per bacterial cell, Vibrio harveyi showed around 200-fold higher maximal quorum sensing-regulated bioluminescence when associated with larvae than in the culture water. Finally, the in vivo quorum sensing activity of mutants defective in the production of one of the three signal molecules is consistent with their virulence, with no detectable in vivo quorum sensing activity in AI-2- and CAI-1-deficient mutants. These results indicate that AI-2 and CAI-1 are the dominant signals during infection of brine shrimp.

  16. Simultaneous Larva Migrans and Larva Currens Caused by Strongyloides stercoralis: A Case Report

    PubMed Central

    Corte, Liliam Dalla; da Silva, Mariana Vale Scribel; Souza, Paulo Ricardo Martins

    2013-01-01

    Strongyloidiasis is an infectious disease caused by the Strongyloides stercoralis larvae, which penetrate the skin, go through the lymphatic circulation, and migrate to the lungs before reaching the intestines. They mature and may cause cutaneous strongyloidiasis, known as larva currens because of the quick migratory rate of the larva. The authors describe a case in which the larvae did not follow their natural lymph route, and after penetrating into the intertriginous area, they migrated to the dermis, developing larva migrans in the early phase, and later associated with the typical lesions of larva currens. The diagnosis was confirmed by the presence of larva in the skin biopsy. PMID:23476820

  17. High-pH-induced flocculation-flotation of the hypersaline microalga Dunaliella salina.

    PubMed

    Besson, Alexandre; Guiraud, Pascal

    2013-11-01

    Natural autoflocculation was not observed in a Dunaliella salina hypersaline culture and the microalgae did not float without destabilization of the algal suspension. High-pH-induced flocculation by sodium hydroxide addition was chosen to induce flotation. Recovery efficiencies greater than 90% and concentration factors of around 20 were reached. An autoflocculation mechanism, with precipitation of magnesium hydroxide, is proposed to explain a sweeping flotation of D. salina cells. The influence of the flow rate of sodium hydroxide addition was also studied to anticipate the constraints related to the industrialization of this process. The flow rate of sodium hydroxide addition had no effect on the recovery efficiency and reduced the concentration factor only for abrupt injections. Natural increase of culture pH by photosynthetic activity could reduce the amount of base consumed. Non-harvested cells remained viable during pH increase and could be used as inoculum for a new culture.

  18. Longitudinal analysis of microbiota in microalga Nannochloropsis salina cultures

    SciTech Connect

    Geng, Haifeng; Sale, Kenneth L.; Tran-Gyamfi, Mary Bao; Lane, Todd W.; Yu, Eizadora T.

    2016-03-08

    Here, large-scale open microalgae cultivation has tremendous potential to make a significant contribution to replacing petroleum-based fuels with biofuels. Open algal cultures are unavoidably inhabited with a diversity of microbes that live on, influence, and shape the fate of these ecosystems. However, there is little understanding of the resilience and stability of the microbial communities in engineered semicontinuous algal systems. To evaluate the dynamics and resilience of the microbial communities in microalgae biofuel cultures, we conducted a longitudinal study on open systems to compare the temporal profiles of the microbiota from two multigenerational algal cohorts, which include one seeded with the microbiota from an in-house culture and the other exogenously seeded with a natural-occurring consortia of bacterial species harvested from the Pacific Ocean. From these month-long, semicontinuous open microalga Nannochloropsis salina cultures, we sequenced a time-series of 46 samples, yielding 8804 operational taxonomic units derived from 9,160,076 high-quality partial 16S rRNA sequences. We provide quantitative evidence that clearly illustrates the development of microbial community is associated with microbiota ancestry. In addition, N. salina growth phases were linked with distinct changes in microbial phylotypes. Alteromonadeles dominated the community in the N. salina exponential phase whereas Alphaproteobacteria and Flavobacteriia were more prevalent in the stationary phase. We also demonstrate that the N. salina-associated microbial community in open cultures is diverse, resilient, and dynamic in response to environmental perturbations. This knowledge has general implications for developing and testing design principles of cultivated algal systems.

  19. An Economic Analysis of Two Groundwater Allocation Programs for the Salinas Valley

    DTIC Science & Technology

    1994-06-01

    to the Monterey County Agricultural Commissioner, the Salinas Valley produces 95 percent of the artichokes , 55 percent of the broccoli, 35 percent of...Product Gallons per Ton Apple Sauce 275 Apricots .2,992 Artichokes 766 Asparagus 808 Brussels Sprout 813 Frozen Fruits 1,780 Garlic 2,800 Onions 1,000...service area contains residential and light industrial users, including the City of Marina, RMC Lonestar, California Artichoke , the Dole Food Company

  20. Nucleotide sequence and expression of the 14-3-3 from the halotolerant alga Dunaliella salina.

    PubMed

    Wang, Tian-yun; Jing, Chang-Qin; Dong, Wei-Hua; Zhang, Jun-He; Zhang, Yu

    2010-02-01

    Previously we reported the nucleotide sequence of a 14-3-3 cDNA cloned from the unicellular green alga Dunaliella salina, however, the nucleotide sequence of this gene have not been reported so far. In the present study, the cloning and characterization of the nucleotide sequence, the gene copy and expression were undertaken. The coding sequence of the gene was found to be interrupted by five introns of 132, 266, 153, 152 and 625 bp, respectively. Introns 3-5 were found in conserved positions as compared to the Chlamydomonas reinhardtii 14-3-3 gene. D. salina 14-3-3 cDNA was inserted into the prokaryotic expression plasmid pET-28 and transformed into E. coli BL21, and the recombinant expressed 14-3-3 protein was purified from E. coli and immunized the rabbit. Indirect ELISA coated with 14-3-3 illustrated that the rabbit antisera titration was 1:1.00E + 06. Western blotting assays confirmed that prepared rabbit antibodies could recognize the recombinant 14-3-3 protein. Southern blotting results showed that there was only one copy of the 14-3-3 present in the genome of D. salina and 14-3-3 expression did not change throughout the Dnualiella cell cycle.

  1. View of the Salinas River Valley area south of Monterey Bay, California

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A vertical view of the Salinas River Valley area south of Monterey Bay, California area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The valley is an irrigated agricultural area, as indicated by the dark-green and light-gray rectangular patterns in the center of the picture. The city of Salinas is barely visible under the cloud cover at the top (north) end of the valley. The dark mass on the left (west) side of the valley is the Santa Lucia mountain range. The Big Sur area is on the left and partly covered by clouds. The Diablo Range forms the dark mass in the lower right (southeast) corner of the photograph. The town of Hillister is the grey area in the dark-green rectangular farm tracts which occupy the floor of the San Benito Valley in the upper right (northeast) corner of the photograph. The Salinas River flows northwestward toward Monterey Bay. The towns of Soleda

  2. Hydrothermal liquefaction of Spirulina and Nannochloropsis salina under subcritical and supercritical water conditions.

    PubMed

    Toor, Saqib S; Reddy, Harvind; Deng, Shuguang; Hoffmann, Jessica; Spangsmark, Dorte; Madsen, Linda B; Holm-Nielsen, Jens Bo; Rosendahl, Lasse A

    2013-03-01

    Six hydrothermal liquefaction experiments on Nannochloropsis salina and Spirulina platensis at subcritical and supercritical water conditions (220–375 °C, 20–255 bar) were carried out to explore the feasibility of extracting lipids from wet algae, preserving nutrients in lipid-extracted algae solid residue, and recycling process water for algae cultivation. GC–MS, elemental analyzer, FT-IR, calorimeter and nutrient analysis were used to analyze bio-crude, lipid-extracted algae and water samples produced in the hydrothermal liquefaction process. The highest bio-crude yield of 46% was obtained on N. salina at 350 °C and 175 bar. For S. platensis algae sample, the optimal hydrothermal liquefaction condition appears to be at 310 °C and 115 bar, while the optimal condition for N. salina is at 350 °C and 175 bar. Preliminary data also indicate that a lipid-extracted algae solid residue sample obtained in the hydrothermal liquefaction process contains a high level of proteins.

  3. Influence of a long duration exposure, 69 months, to the space flight factors in Artemia cysts, tobacco and rice seeds

    NASA Astrophysics Data System (ADS)

    Planel, H.; Gaubin, Y.; Pianezzi, B.; Delpoux, M.; Bayonove, J.; Bès, J. C.; Heilmann, C.; Gasset, G.

    1994-10-01

    Three french laboratories have participated in the Free Flyer Biostack experiment. Artemia cysts, tobacco seeds and rice caryopsis and embryos were used. Biological objects in monolayers were dead. In opposite, a large fraction of samples used in bulk survived. A stimulatory effect occurred in the first steps of development in Artemia cysts. In fact, the larval survival was unchanged or slightly reduced. In tobacco a drastic decrease in germination and survival rate was observed. Space flight did not induce genetic changes. In rice, results depend on the variety which was investigated; the growth rate stimulation in flight samples is discussed with respect to controls.

  4. Physical, biochemical and functional characterization of haemoglobin from three strains of Artemia.

    PubMed

    Sugumar, Vasudevan; Munuswamy, Natesan

    2007-02-01

    The brine shrimp, Artemia, an inhabitant of coastal and inland salterns, encounter fluctuations in the salinity which in turn influences the oxygen availability of their habitat. Hence, experiments were performed to analyze variations in haemoglobin structure and patterns of three strains of Artemia from South India and also to reflect the effect of varying oxygen levels in their habitat. Haemoglobins were purified on a DEAE-Sephadex column and haemoglobin types were analyzed by comparing their relative mobility on a non-denaturing medium. Furthermore, their molecular masses were determined by gel filtration in Sepharose column and by dodecylsulfate polyacrylamide gel electrophoresis. Results clearly reveal the presence of three distinct extracellular haemoglobins Hb I, Hb II and Hb III in Tuticorin strain while the other strains displayed only trails or the complete absence of Hb III and Hb II. Estimated molecular masses of these haemoglobins are 235,000-250,000 Da. Denaturation of the reduced and alkylated haemoglobins revealed apparently one polypeptide chain with a molecular mass of 124,000 Da. Upon denaturing gel electrophoresis of native haemoglobin Hb II, it was found that the 124,000 Da, polypeptide was cleaved specifically into two unequally-sized fragments of 50,400 and 79,800 Da. With regard to oxygen affinity, Hb III has a very high affinity for oxygen, an almost negligible Bohr effect and a good physiological adaptation to temperature changes. By combining the three haemoglobins in different proportions Artemia strains must be able to withstand diverging environmental conditions. In particular, the absence of Hb III in Puthalam and its occurrence as a faint band in Thamaraikulam could be correlated to the oxygen levels of their habitats.

  5. Evolutionary Origin and Phylogeography of the Diploid Obligate Parthenogen Artemia parthenogenetica (Branchiopoda: Anostraca)

    PubMed Central

    Green, Andy J.; Figuerola, Jordi; Amat, Francisco; Rico, Ciro

    2010-01-01

    Background Understanding the evolutionary origin and the phylogeographic patterns of asexual taxa can shed light on the origin and maintenance of sexual reproduction. We assessed the geographic origin, genetic diversity, and phylogeographic history of obligate parthenogen diploid Artemia parthenogenetica populations, a widespread halophilic crustacean. Methodology/Principal Findings We analysed a partial sequence of the Cytochrome c Oxidase Subunit I mitochondrial gene from an extensive set of localities (including Eurasia, Africa, and Australia), and examined their phylogeographic patterns and the phylogenetic relationships of diploid A. parthenogenetica and its closest sexual relatives. Populations displayed an extremely low level of mitochondrial genetic diversity, with one widespread haplotype shared by over 79% of individuals analysed. Phylogenetic and phylogeographic analyses indicated a multiple and recent evolutionary origin of diploid A. parthenogenetica, and strongly suggested that the geographic origin of parthenogenesis in Artemia was in Central Asia. Our results indicate that the maternal sexual ancestors of diploid A. parthenogenetica were an undescribed species from Kazakhstan and A. urmiana. Conclusions/Significance We found evidence for multiple origin of parthenogenesis in Central Asia. Our results indicated that, shortly after its origin, diploid A. parthenogenetica populations underwent a rapid range expansion from Central Asia towards the Mediterranean region, and probably to the rest of its current geographic distribution. This contrasts with the restricted geographic distribution, strong genetic structure, and regional endemism of sexual Artemia lineages and other passively dispersed sexual continental aquatic invertebrates. We hypothesize that diploid parthenogens might have reached their current distribution in historical times, with a range expansion possibly facilitated by an increased availability of suitable habitat provided by

  6. May arsenic pollution contribute to limiting Artemia franciscana invasion in southern Spain?

    PubMed Central

    Taggart, Mark A.; Green, Andy J.

    2016-01-01

    Limited information exists regarding the complex interactions between biological invasions, pollution, and climate change. Most studies indicate that pollution tends to favor invasive species. Here, we provide evidence that arsenic (As) pollution may have a role in limiting the invasion of the exotic brine shrimp Artemia franciscana. We tested As toxicity in natural populations of Artemia parthenogenetica (a native taxon) and A. franciscana from localities in southern Spain with differing degrees of As contamination. Tests were conducted both under current mean temperature conditions (25 °C), and as per a future climate scenario (i.e., an increase in mean temperature of 4 °C). Acute toxicity was estimated on the basis of the median lethal concentration (at 24 h), and chronic toxicity was evaluated by measuring Artemia survival and growth under sublethal exposures (after 26 days). At 25 °C, native A. parthenogenetica from the highly polluted Odiel and Tinto estuary was much more resistant to acute As stress (LC50-24 h, 24.67 mg L−1) than A. franciscana (15.78 mg L−1) and A. parthenogenetica from unpolluted sites (12.04 mg L−1)–suggesting that local adaptation to polluted conditions may occur. At 29 °C, resistance of A. parthenogenetica from Odiel decreased significantly, and there were no statistical differences in sensitivity between the three species/populations, suggesting that climate change may enhance the probability of invasion. Resistance increased with developmental stage from nauplii to adults, and was extremely high in cysts which still hatched at As concentrations of up to 6400 mg L−1. Under sublethal chronic exposure A. franciscana performed better (survival and growth) than A. parthenogenetica, and both species experienced a faster growth when exposed to As, compared with unexposed (control) individuals, probably due to the hormesis. We discuss the ecological implications of our results. PMID:26925327

  7. Identification and characterization of a Masculinizer (Masc) gene involved in sex differentiation in Artemia.

    PubMed

    Li, Dong-Rui; Ye, Hui-Li; Yang, Jin-Shu; Yang, Fan; Wang, Mo-Ran; De Vos, Stephanie; Vuylsteke, Marnik; Sorgeloos, Patrick; Van Stappen, Gilbert; Bossier, Peter; Yang, Wei-Jun

    2017-03-11

    The sex of relatively primitive animals such as invertebrates is mostly determined by environmental factors and chromosome ploidy. Heteromorphic chromosomes may also play an important role, as in the ZW system in lepidopterans. However, the mechanisms of these various sex determination systems are still largely undefined. In the present study, a Masculinizer gene (Ar-Masc) was identified in the crustacean Artemia franciscana Kellogg 1906. Sequence analysis revealed that the 1140-bp full-length open reading frame of Ar-Masc encodes a 380-aa protein containing two CCCH-type zinc finger domains having a high degree of shared identities with the MASC protein characterized in the silkworm Bombyx mori, which has been determined to participate in the production of male-specific splice variants. Furthermore, although Ar-Masc could be detected in almost all stages in both sexual and parthenogenetic Artemia, there were significant variations in expression between these two reproductive modes. Firstly, qRT-PCR and Western blot analysis showed that levels of both Ar-Masc mRNA and protein in sexual nauplii were much higher than in parthenogenetic nauplii throughout the hatching process. Secondly, both sexual and parthenogenetic Artemia had decreased levels of Ar-Masc along with the embryonic developmental stages, while the sexual ones had a relatively higher and more stable expression than those of parthenogenetic ones. Thirdly, immunofluorescence analysis determined that sexual individuals had higher levels of Ar-MASC protein than parthenogenetic individuals during embryonic development. Lastly, RNA interference with dsRNA showed that gene silencing of Ar-Masc in sexual A. franciscana caused the female-male ratio of progeny to be 2.19:1. These data suggest that Ar-Masc participates in the process of sex determination in A. franciscana, and provide insight into the evolution of sex determination in sexual organisms.

  8. Intentional introduction of Artemia sinica (Anostraca) in the high-altitude Tibetan lake Dangxiong Co: the new population and consequences for the environment and for humans

    NASA Astrophysics Data System (ADS)

    Jia, Qinxian; Anufriieva, Elena; Liu, Xifang; Kong, Fanjing; Shadrin, Nickolai

    2015-11-01

    The imbalance between supply and demand of Artemia cysts in China and around the world is increasing now. Salt lakes in Tibet may contribute to the solution of the problem. In Northern Tibet there are 26 saline lakes whose salinity and temperature may support Artemia survival at an altitude of 4 000-5 100 m. We found Artemia in 15 of these lakes. The saline lakes with Artemia populations mainly belong to the shallow basin lakes, and the majority of these lakes are small in area. The total area of lakes without Artemia is more than 1 000 km2. Lake Dangxiong Co (Co means lake in Tibet) was chosen for the intentional introduction of Artemia sinica. In 2004, 850 g of A. sinica cysts, originating from Qinghai, were introduced in the lake. Surveys in 2006-2014 showed that the average abundance of Artemia adults in the lake gradually increased from 20 ind./m3 in 2006 to 1950 ind./m3 in 2013. We assume that two subpopulations of A. sinica, separated by depth, may exist in the lake. The new Artemia population caused an increase in the number of species of phytoplankton and heterotrophic protozoa with a decrease of their total abundance. Water transparency also increased. Dominance in phytoplankton passed from cyanobacteria to diatoms. Changes occurred not only in the lake ecosystem; the number of water birds using the lakes also dramatically increased. Preliminary calculations showed that is it possible to harvest at least about 150 t cysts per year from the lake as well as 3.2 thousand tons of frozen or 350 t of dried biomass of adult Artemia.

  9. Comparative analysis on the key enzymes of the glycerol cycle metabolic pathway in Dunaliella salina under osmotic stresses.

    PubMed

    Chen, Hui; Lu, Yan; Jiang, Jian-Guo

    2012-01-01

    The glycerol metabolic pathway is a special cycle way; glycerol-3-phosphate dehydrogenase (G3pdh), glycerol-3-phosphate phosphatase (G3pp), dihydroxyacetone reductase (Dhar), and dihydroxyacetone kinase (Dhak) are the key enzymes around the pathway. Glycerol is an important osmolyte for Dunaliella salina to resist osmotic stress. In this study, comparative activities of the four enzymes in D. salina and their activity changes under various salt stresses were investigated, from which glycerol metabolic flow direction in the glycerol metabolic pathway was estimated. Results showed that the salinity changes had different effects on the enzymes activities. NaCl could stimulate the activities of all the four enzymes in various degrees when D. salina was grown under continuous salt stress. When treated by hyperosmotic or hypoosmotic shock, only the activity of G3pdh in D. salina was significantly stimulated. It was speculated that, under osmotic stresses, the emergency response of the cycle pathway in D. salina was driven by G3pdh via its response to the osmotic stress. Subsequently, with the changes of salinity, other three enzymes started to respond to osmotic stress. Dhar played a role of balancing the cycle metabolic pathway by its forward and backward reactions. Through synergy, the four enzymes worked together for the effective flow of the cycle metabolic pathways to maintain the glycerol requirements of cells in order to adapt to osmotic stress environments.

  10. Developmental and reproductive effects of low cadmium concentration on Artemia parthenogenetica.

    PubMed

    Sarabia, Raquel; Del Ramo, Jose; Díaz-Mayans, Javier; Torreblanca, Amparo

    2003-06-01

    Hatching, reproductive, and lifespan characteristics of an Artemia parthenogenetica population from La Mata (Alicante, Spain) exposed to cadmium were studied. No effects on percentage of cyst hatched nor time of hatching were observed on cysts exposed from 0.01 to 5 mg Cd/L. Cohorts of Artemia were chronically exposed to cadmium in life-table experiments to test whether ecologically relevant impacts may occur after several generations of exposure to a very low concentration of cadmium. Chronic toxicity tests were performed using neonates of a third generation of shrimps exposed to 0.08 mg Cd/L (1/1000 of the LOEC for 24 h acute toxicity test). No significant reduction in the intrinsic rate of natural increase (rm) was found as a result of cadmium exposure, although the age-specific fecundities of the cadmium exposed shrimps were lower than those of the controls. A significant decrease in the prereproductive period and a reduction in the percentage of fertile females was also found as a consequence of the metal exposure.

  11. A proteomic study on postdiapaused embryonic development of brine shrimp (Artemia franciscana).

    PubMed

    Wang, Weiwei; Meng, Bo; Chen, Weihua; Ge, Xiaomeng; Liu, Siqi; Yu, Jun

    2007-10-01

    Encysted gastrula of brine shrimp (Artemia, Crustacea, and Anostraca) provides an excellent model for studying molecular processes of diapause. We report a proteomic study on early molecular responses of Artemia's postdiapaused cysts and found that dehydrated cysts actually store more proteins, in both kind and amount, than developing cysts. We identified 75 differentially expressed proteins over a course of cyst development, and also exploited PTMs of dehydrate cysts. We further surveyed gene expression of postdiapaused cysts in early developmental phases in a 0.5 h interval up to the seventh hour, and discovered that the activation of cellular activities is ignited as early as 0.5 h after rehydration. We traced nine differentially expressed proteins (COXI, COXIII, heat shock proteins (HSP26, HSP60, and HSP70), CDC48, late embryogenesis abundant (LEA), GS1-like protein, and cathepsin L-associated protein (CLAP)) for quantitative transcriptional changes, monitored by real-time PCR, and found these proteins exhibiting distinct expression patterns that suggest complex gene regulations for cyst reactivation after diapause breakage. Future experiments should be designed to focus on early activation concerning signal transduction, energy generation, and PTMs.

  12. Immunostimulatory nature of beta-glucans and baker's yeast in gnotobiotic Artemia challenge tests.

    PubMed

    Marques, Antonio; Dhont, Jean; Sorgeloos, Patrick; Bossier, Peter

    2006-05-01

    The use of new preventive approaches such as immunostimulants to reduce stress and mortalities, to maintain good health of cultured organisms and to stimulate the non-specific defence mechanism, is becoming increasingly important in aquaculture. Yet detailed analysis reveals that in most experiments the validity of some conclusions with respect to the benefit of immunostimulation is still doubtful, especially in invertebrates. The use of standardized trials under controlled rearing conditions, complemented with fundamental research on defence mechanisms can provide unequivocal evidence for the beneficial effects of immunostimulants in reducing invertebrate susceptibility to diseases or infections. This study investigated the use of small amounts of baker's yeast Saccharomyces cerevisiae and glucan particles (obtained from baker's yeast) in gnotobiotic Artemia to overcome the pathogenicity of two organisms: Vibrio campbellii and V proteolyticus. Artemia supplemented with small quantities of a yeast strain presenting higher concentrations of beta-glucans or with glucan particles seemed to completely resist the detrimental effects of both pathogens. The higher amount and/or availability of beta-glucans in that yeast might play an essential role in such protection, as most probably glucans stimulate the immune response of the nauplii.

  13. Diffusive properties of water in Artemia cysts as determined from quasi-elastic neutron scattering spectra.

    PubMed Central

    Trantham, E C; Rorschach, H E; Clegg, J S; Hazlewood, C F; Nicklow, R M; Wakabayashi, N

    1984-01-01

    Results have been obtained on the quasi-elastic spectra of neutrons scattered from pure water, a 20% agarose gel (hydration four grams H2O per gram of dry solid) and cysts of the brine shrimp Artemia for hydrations between 0.10 and 1.2 grams H2O per gram of dry solids. The spectra were interpreted using a two-component model that included contributions from the covalently bonded protons and the hydration water, and a mobile water fraction. The mobile fraction was described by a jump-diffusion correlation function for the translation motion and a simple diffusive orientational correlation function. The results for the line widths gamma (Q2) for pure water were in good agreement with previous measurements. The agarose results were consistent with NMR measurements that show a slightly reduced translational diffusion for the mobile water fraction. The Artemia results show that the translational diffusion coefficient of the mobile water fraction was greatly reduced from that of pure water. The line width was determined mainly by the rotational motion, which was also substantially reduced from the pure water value as determined from dielectric relaxation studies. The translational and rotational diffusion parameters were consistent with the NMR measurements of diffusion and relaxation. Values for the hydration fraction and the mean square thermal displacement [u2] as determined from the Q-dependence of the line areas were also obtained. PMID:6733243

  14. Selected bacterial strains protect Artemia spp. from the pathogenic effects of Vibrio proteolyticus CW8T2.

    PubMed

    Verschuere, L; Heang, H; Criel, G; Sorgeloos, P; Verstraete, W

    2000-03-01

    In this study Vibrio proteolyticus CW8T2 has been identified as a virulent pathogen for Artemia spp. Its infection route has been visualized with transmission electron microscopy. The pathogen affected microvilli and gut epithelial cells, disrupted epithelial cell junctions, and reached the body cavity, where it devastated cells and tissues. In vivo antagonism tests showed that preemptive colonization of the culture water with nine selected bacterial strains protected Artemia juveniles against the pathogenic effects. Two categories of the selected strains could be distinguished: (i) strains providing total protection, as no mortality occurred 2 days after the experimental infection with V. proteolyticus CW8T2, with strain LVS8 as a representative, and (ii) strains providing partial protection, as significant but not total mortality was observed, with strain LVS2 as a representative. The growth of V. proteolyticus CW8T2 in the culture medium was slowed down in the presence of strains LVS2 and LVS8, but growth suppression was distinctly higher with LVS8 than with LVS2. It was striking that the strains that gave only partial protection against the pathogen in the in vivo antagonism test showed also a restricted capability to colonize the Artemia compared to the strains providing total protection. The in vivo antagonism tests and the filtrate experiments showed that probably no extracellular bacterial compounds were involved in the protective action but that the living cells were required to protect Artemia against V. proteolyticus CW8T2.

  15. Morphological differentiation of seven parthenogenetic Artemia (Crustacea: Branchiopoda) populations from China, with special emphasis on ploidy degrees.

    PubMed

    Asem, Alireza; Sun, Shi-Chun

    2016-04-01

    Parthenogenetic Artemia from seven Chinese locations with different elevations and various ploidies are characterized by phenotypic and morphometric analyses. Our findings show that the studied populations exhibit dissimilar patterns of ovisac. Four phenotypic patterns of furca are qualified and one of them is shared among di-, tetra- and pentaploid Artemia. Results of discriminant analysis based on morphometric data reveal that tetra- and pentaploid populations are grouped together, but the Aqqikkol Lake population is clearly differentiated. Previous hypothesis/conclusion that polyploid Artemia are larger than diploids is only partly supported by the present results, which show that pentaploid and tetraploid populations are larger than the mostly diploid populations in terms of the total length, but the body size of the Aibi Lake triploids has not significant difference with the sympatric diploids and the mostly diploid Aqqikkol population that inhabit in very high altitude has the largest body size among all parthenogenetic populations. The founding confirms that body size of Artemia is following with Bergmann's rule.

  16. Evaluation of commercial Artemia enrichment products on growth, survival, stress tolerance, and fatty acid composition of larval Florida pompano

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rearing live feed organisms represents the majority of time and labor associated with larviculture operations vital to the seed stock supply of marine finfish aquaculture production facilities. No information exists with respect to optimal Artemia enrichment protocols for Florida pompano Trachinotu...

  17. Does a change from whole to powdered food (Artemia franciscana eggs) increase oviposition in the ladybird Coleomegilla maculata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered versus whole Artemia franciscana (brine shrimp) eggs with or without a dietary supplement on devel...

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

    PubMed

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

    2016-09-01

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

  19. Single stimulus learning in zebrafish larvae

    PubMed Central

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

    2014-01-01

    Learning about a moving visual stimulus was examined in zebrafish larvae using an automated imaging system and a t1-t2 design. In three experiments, zebrafish larvae were exposed to one of two inputs at t1 (either a gray bouncing disk or an identical but stationary disk) followed by a common test at t2 (the gray bouncing disk). Using 7 days post-fertilization (dpf) larvae and 12 stimulus exposures, Experiment 1 established that these different treatments produced differential responding to the moving disk during testing. Larvae familiar with the moving test stimulus were significantly less likely to be still in its presence than larvae that had been exposed to the identical but stationary stimulus. Experiment 2 confirmed this result in 7 dpf larvae and extended the finding to 5 and 6 dpf larvae. Experiment 3 found differential responding to the moving test stimulus with 4 or 8 stimulus exposures but not with just one exposure in 7 dpf larvae. These results provide evidence for learning in very young zebrafish larvae. The merits and challenges of the t1-t2 framework to study learning are discussed. PMID:24012906

  20. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    SciTech Connect

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  1. Cloning and genomic nucleotide sequence of the matrix attachment region binding protein from the halotolerant alga Dunaliella salina.

    PubMed

    Wang, Peng-Ju; Wang, Tian-Yun; Wang, Ya-Feng; Yang, Rui; Li, Zhao-Xi

    2013-07-01

    In our previous study, the sequence of a matrix attachment region binding protein (MBP) cDNA was cloned from the unicellular green alga Dunaliella salina. However, the nucleotide sequence of this gene has not been reported so far. In this paper, the nucleotide sequence of MBP was cloned and characterized, and its gene copy number was determined. The MBP nucleotide sequence is 5641 bp long, and interrupted by 12 introns ranging from 132 to 562 bp. All the introns in the D. salina MBP gene have orthodox splice sites, exhibiting GT at the 5' end and AG at the 3' end. Southern blot analysis showed that MBP only has one copy in the D. salina genome.

  2. Two p90 ribosomal S6 kinase isoforms are involved in the regulation of mitotic and meiotic arrest in Artemia.

    PubMed

    Duan, Ru-Bing; Zhang, Li; Chen, Dian-Fu; Yang, Fan; Yang, Jin-Shu; Yang, Wei-Jun

    2014-06-06

    There are multiple isoforms of p90 ribosomal S6 kinase (RSK), which regulate diverse cellular functions such as cell growth, proliferation, maturation, and motility. However, the relationship between the structures and functions of RSK isoforms remains undetermined. Artemia is a useful model in which to study cell cycle arrest because these animals undergo prolonged diapauses, a state of obligate dormancy. A novel RSK isoform was identified in Artemia, which was termed Ar-Rsk2. This isoform was compared with an RSK isoform that we previously identified in Artemia, termed Ar-Rsk1. Ar-Rsk2 has an ERK-docking motif, whereas Ar-Rsk1 does not. Western blot analysis revealed that Ar-Rsk1 was activated by phosphorylation, which blocked meiosis in oocytes. Knockdown of Ar-Rsk1 reduced the level of phosphorylated cdc2 and thereby suppressed cytostatic factor activity. This indicates that Ar-Rsk1 regulates the cytostatic factor in meiosis. Expression of Ar-Rsk2 was down-regulated in Artemia cysts in which mitosis was arrested. Knockdown of Ar-Rsk2 resulted in decreased levels of cyclin D3 and phosphorylated histone H3, and the production of pseudo-diapause cysts. This indicates that Ar-Rsk2 regulates mitotic arrest. PLK and ERK RNAi showed that Ar-Rsk2, but not Ar-Rsk1, could be activated by PLK-ERK in Artemia. This is the first study to report that RSK isoforms with and without an ERK-docking motif regulate mitosis and meiosis, respectively. This study provides insight into the relationship between the structures and functions of RSK isoforms.

  3. Valorization of the aqueous phase obtained from hydrothermally treated Dunaliella salina remnant biomass.

    PubMed

    Pirwitz, Kristin; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2016-11-01

    Up to 90% of Dunaliella salina biomass remains unused after extraction of the main product β-carotene. The potential of mild hydrothermal liquefaction (HTL) to exploit this biomass as a source of valuable by-products was assessed. The results indicate that 80% of the remnant was converted into glucose by mild HTL (100°C, 0min). The recovered glucose was successfully used as a carbon source to cultivate biotechnologically relevant microorganisms, namely Chlorella vulgaris, Escherichia coli and Saccharomyces cerevisiae. Furthermore, the analysis of energy demand and operating costs confirms the beneficial effect of mild liquefaction on the overall process economics of algal β-carotene production.

  4. Map of the Rinconada and Reliz Fault Zones, Salinas River Valley, California

    USGS Publications Warehouse

    Rosenberg, Lewis I.; Clark, Joseph C.

    2009-01-01

    The Rinconada Fault and its related faults constitute a major structural element of the Salinas River valley, which is known regionally, and referred to herein, as the 'Salinas Valley'. The Rinconada Fault extends 230 km from King City in the north to the Big Pine Fault in the south. At the south end of the map area near Santa Margarita, the Rinconada Fault separates granitic and metamorphic crystalline rocks of the Salinian Block to the northeast from the subduction-zone assemblage of the Franciscan Complex to the southwest. Northwestward, the Rinconada Fault lies entirely within the Salinian Block and generally divides this region into two physiographically and structurally distinct areas, the Santa Lucia Range to the west and the Salinas Valley to the east. The Reliz Fault, which continues as a right stepover from the Rinconada Fault, trends northwestward along the northeastern base of the Sierra de Salinas of the Santa Lucia Range and beyond for 60 km to the vicinity of Spreckels, where it is largely concealed. Aeromagnetic data suggest that the Reliz Fault continues northwestward another 25 km into Monterey Bay, where it aligns with a high-definition magnetic boundary. Geomorphic evidence of late Quaternary movement along the Rinconada and Reliz Fault Zones has been documented by Tinsley (1975), Dibblee (1976, 1979), Hart (1976, 1985), and Klaus (1999). Although definitive geologic evidence of Holocene surface rupture has not been found on these faults, they were regarded as an earthquake source for the California Geological Survey [formerly, California Division of Mines and Geology]/U.S. Geological Survey (CGS/USGS) Probabilistic Seismic Hazards Assessment because of their postulated slip rate of 1+-1 mm/yr and their calculated maximum magnitude of 7.3. Except for published reports by Durham (1965, 1974), Dibblee (1976), and Hart (1976), most information on these faults is unpublished or is contained in theses, field trip guides, and other types of reports

  5. Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

    PubMed

    Tian, Jiyuan; Yu, Juan

    2009-12-02

    Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina.

  6. SNP detection in Na/K ATP-ase gene α1 subunit of bisexual and parthenogenetic Artemia strains by RFLP screening.

    PubMed

    Manaffar, R; Zare, S; Agh, N; Abdolahzadeh, N; Soltanian, S; Sorgeloos, P; Bossier, P; Van Stappen, G

    2011-01-01

    In order to find a marker for differentiating between a bisexual and a parthenogenetic Artemia strain, Exon-7 of the Na/K ATPase α(1) subunit gene was screened by RFLP technique. The results revealed a constant synonymous SNP (single nucleotide polymorphism) in digestion by the Tru1I enzyme that was consistent with these two types of Artemia. This SNP was identified as an accurate molecular marker for discrimination between bisexual and parthenogenetic Artemia. According to the Nei's genetic distance (1973), the lowest genetic distance was found between individuals from Artemia urmiana Günther 1890 and parthenogenetic populations, making the described marker the first marker to easily distinguish between these two cooccurring species.

  7. Workbook on Identification of Aedes Aegypti Larvae.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; And Others

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

  8. Multigenerational demographic responses of sexual and asexual Artemia to chronic genotoxicity by a reference mutagen.

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-11-15

    Genotoxins are capable of multigenerational impacts on natural populations via DNA damage and mutations. Sexual reproduction is assumed to reduce the long term consequences of genotoxicity for individual fitness and should therefore reduce population level effects. However, rather few empirical studies have quantified the magnitude of this effect. We tried to analyse the multigenerational demographic responses of sexual Artemia franciscana and asexual Artemia parthenogenetica due to chronic genotoxicity by a reference mutagen, ethyl methane sulfonate (EMS). A prospective (elasticity analysis) and retrospective (differences and contributions) perturbation analysis was carried out to understand the interactions of life history traits with population growth rate λ by comparing elasticities, differences and contributions of vital rates to λ. None of the previous studies have compared the effects of chronic genotoxicity using prospective and retrospective perturbation analyses in a sexual and asexual species over generations. The behaviour of a population with lower growth rate in the presence of genotoxicants in the field was studied by simulating reduced fertilities in the LTRE design. The results of prospective and retrospective perturbation analyses of effects on λ showed that population growth rate was proportionally more sensitive to juvenile survival whereas the effect of EMS on juvenile fertility contributed more to the variations in population growth rate in both the species and this effect was due to the high growth rate of Artemia. Simulations of lower population growth rate in the model showed that adult fertility and survival are also of importance. Sexual reproduction substantially mitigated the long term consequences of genetic damage, although these would be greater if population growth rate were lower. So multigenerational population level consequences of genotoxicity were much greater in an asexual species. So asexual species, and those with a

  9. The effect of live feeds bathed with the red seaweed Asparagopsis armata on the survival, growth and physiology status of Sparus aurata larvae.

    PubMed

    Castanho, S; Califano, G; Soares, F; Costa, R; Mata, L; Pousão-Ferreira, P; Ribeiro, L

    2017-03-17

    Larval rearing is affected by a wide range of microorganisms that thrive in larviculture systems. Some seaweed species have metabolites capable of reducing the bacterial load. However, no studies have yet tested whether including seaweed metabolites on larval rearing systems has any effects on the larvae development. This work assessed the development of Sparus aurata larvae fed preys treated with an Asparagopsis armata product. Live prey, Brachionus spp. and Artemia sp., were immersed in a solution containing 0.5% of a commercial extract of A. armata (Ysaline 100, YSA) for 30 min, before being fed to seabream larvae (n = 4 each). In the control, the live feed was immersed in clear water. Larval parameters such as growth, survival, digestive capacity (structural-histology and functional-enzymatic activity), stress level (cortisol content), non-specific immune response (lysozyme activity), anti-bacterial activity (disc-diffusion assay) and microbiota quantification (fish larvae gut and rearing water) were monitored. Fish larvae digestive capacity, stress level and non-specific immune response were not affected by the use of YSA. The number of Vibrionaceae was significantly reduced both in water and larval gut when using YSA. Growth was enhanced for YSA treatment, but higher mortality was also observed, especially until 10 days after hatching (DAH). The mortality peak observed at 8 DAH for both treatments, but higher for YSA, indicates larval higher susceptibility at this development stage, suggesting that lower concentrations of YSA should be used until 10 DAH. The application of YSA after 10 DAH onwards promotes a safer rearing environment.

  10. Influence of different yeast cell-wall mutants on performance and protection against pathogenic bacteria (Vibrio campbellii) in gnotobiotically-grown Artemia.

    PubMed

    Soltanian, Siyavash; Dhont, Jean; Sorgeloos, Patrick; Bossier, Peter

    2007-07-01

    A selection of isogenic yeast strains (with deletion for genes involved in cell-wall synthesis) was used to evaluate their nutritional and immunostimulatory characteristics for gnotobiotically-grown Artemia. In the first set of experiments the nutritional value of isogenic yeast strains (effected in mannoproteins, glucan, chitin and cell-wall bound protein synthesis) for gnotobiotically-grown Artemia was studied. Yeast cell-wall mutants were always better feed for Artemia than the isogenic wild type mainly because they supported a higher survival but not a stronger individual growth. The difference in Artemia performance between WT and mutants feeding was reduced when stationary-phase grown cells were used. These results suggest that any mutation affecting the yeast cell-wall make-up is sufficient to improve the digestibility in Artemia. The second set of experiments, investigates the use of a small amount of yeast cells in gnotobiotic Artemia to overcome pathogenicity of Vibrio campbellii (VC). Among all yeast cell strains used in this study, only mnn9 yeast (less cell-wall bound mannoproteins and more glucan and chitin) seems to completely protect Artemia against the pathogen. Incomplete protection against the pathogen was obtained by the gas1 and chs3 mutants, which are lacking the gene for a particular cell-wall protein and chitin synthesis, respectively, resulting in more glucan. The result with the chs3 mutant is of particular interest, as its nutritional value for Artemia is comparable to the wild type. Hence, only with the chs3 strain, in contrast to the gas1 or mnn9 strains, the temporary protection to VC is not concomitant with a better growth performance under non-challenged conditions, suggesting non-interference of general nutritional effects.

  11. Map showing landslides and areas of potential landsliding in the Salina quadrangle, Utah

    USGS Publications Warehouse

    Williams, Paul L.

    1972-01-01

    The term “landslide” is broadly defined as any “downward and outward movement of slope-forming materials composed of natural rock, soils, artificial fills, or combinations of these materials. The moving mass may proceed by any one of three principal types of movement: falling, sliding, or flossing, or by their combinations” (Varnes, 1958). Landslides and areas of potential landslides are fairly common in the rugged terrain of the Salina quadrangle. In much of the western half of the map area, relatively high rainfall, steep slopes, and flat layers of hard rock on top of very soft incompetent rock all favor landsliding, chiefly as slides and earth flows. In arid parts of the quadrangle, principally in the east half, alternating flat layers of hard and soft rocks are eroded to bare cliffs separated by benches, and rockfalls are the dominant type of landsliding. Landslides were more active in the wetter climate of the Pleistocene Epoch, which ended several thousand years ago (Smith and others, 1963, p. 52). Although landslide deposits are abundant in the Salina quadrangle, few landslide movements have been documented during historic time, partly because landslides are generally less active now than during Pleistocene times, partly because movement is commonly very slow and thus escapes notice, and partly because of the remoteness and sparse population of the area.

  12. Comparison of sequences formed in Marine sabkha (subaerial) and salina (Subaqueous) settings-modern and ancient

    SciTech Connect

    Warren, J.K.; St. Kendall, C.G.

    1985-06-01

    Marine evaporites occurring in modern subaqueous (salina) settings and subaerial (sabkha) settings are different. Subaqueous Holocene evaporites occur as shoalingupward lacustrine sequences up to 10 m thick. They are evaporite dominated and are composed primarily of bottom-nucleated crystals that may be deposited as massive, laminated, or rippled units. Each coastal lake is dominated by laminated evaporites with subordinate carbonate sediments. In plan view, they show a well-developed bull's-eye pattern with a sulfate center and a carbonate rim. In contrast, subaerial (sabkha) evaporites occur as part of a laterally prograding, shoaling-upward, peritidal sequence in which the supratidal unit is usually no more than 1 m thick. Sabkha sequences are matrix dominated, not evaporite dominated, with the bulk of the sulfate phase occurring as diagenetic nodules, enteroliths, or diapirlike structures. These sulfates were formed during syndepositional diagenesis by replacement and displacement processes. The various facies of the sequence tend to accumulate in belts parallel with the shoreline. Relative to the sea level or the brine level, sabkhas tend to form over paleotopographic highs whereas salinas tend to occur in paleotopographic lows. Some of the characteristics that distinguish Holocene subaerial and subaqueous evaporite sequences can be used to do the same for similar ancient facies, even when gypsum has been converted to nodular anhydrite. The distinction is important for it can be used by explorationists in the oil industry to define the paleotopography of the associated underlying porous and nonporous carbonates.

  13. Evaluation of hydrologic conditions and nitrate concentrations in the Rio Nigua de Salinas alluvial fan aquifer, Salinas, Puerto Rico, 2002-03

    USGS Publications Warehouse

    Rodriguez, Jose M.

    2006-01-01

    A ground-water quality study to define the potential sources and concentration of nitrate in the Rio Nigua de Salinas alluvial fan aquifer was conducted between January 2002 and March 2003. The study area covers about 3,600 hectares of the coastal plain within the municipality of Salinas in southern Puerto Rico, extending from the foothills to the Caribbean Sea. Agriculture is the principal land use and includes cultivation of diverse crops, turf grass, bioengineered crops for seed production, and commercial poultry farms. Ground-water withdrawal in the alluvial fan was estimated to be about 43,500 cubic meters per day, of which 49 percent was withdrawn for agriculture, 42 percent for public supply, and 9 percent for industrial use. Ground-water flow in the study area was primarily to the south and toward a cone of depression within the south-central part of the alluvial fan. The presence of that cone of depression and a smaller one located in the northeastern quadrant of the study area may contribute to the increase in nitrate concentration within a total area of about 545 hectares by 'recycling' ground water used for irrigation of cultivated lands. In an area that covers about 405 hectares near the center of the Salinas alluvial fan, nitrate concentrations increased from 0.9 to 6.7 milligrams per liter as nitrogen in 1986 to 8 to 12 milligrams per liter as nitrogen in 2002. Principal sources of nitrate in the study area are fertilizers (used in the cultivated farmlands) and poultry farm wastes. The highest nitrogen concentrations were found at poultry farms in the foothills area. In the area of disposed poultry farm wastes, nitrate concentrations in ground water ranged from 25 to 77 milligrams per liter as nitrogen. Analyses for the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate were used to distinguish the source of nitrate in the coastal plain alluvial fan aquifer. Potential nitrate loads from areas under cultivation were estimated for the

  14. Effects of salinity and ultraviolet radiation on the bioaccumulation of mycosporine-like amino acids in Artemia from Lake Urmia (Iran).

    PubMed

    Khosravi, Sanaz; Khodabandeh, Saber; Agh, Naser; Bakhtiarian, Mahdieh

    2013-01-01

    We investigated the effects of salinity and artificial UV radiation on the accumulation of mycosporine-like amino acids (MAAs) in sexual and parthenogenetic Artemia from Lake Urmia. The nauplii hatched from the cysts were cultured until adulthood under two salinities (150 and 250 g L(-1) ) and two light treatments (PAR and PAR+UVR) in the laboratory. Finally, the Artemia were analyzed for their concentration of MAAs. In most of the cases, the higher salinity level applied was found to increase the MAA concentrations in both Artemia populations significantly. The acquisition efficiency of MAAs in both Artemia populations increased under exposure to UVR-supplemented photosynthetically active radiation (PAR) compared to those raised under PAR, except for Porphyra-334. It was observed that combination of UV radiation and elevated salinity significantly increased the bioaccumulation of MAAs. Thus, the presence of these compounds in these populations of Artemia may increase their adaptability for living in high-UV and high-salinity conditions prevailing in Lake Urmia. Higher concentrations of MAAs in the parthenogenetic population of Artemia could be probably attributed to its mono sex nature and higher adaptation capacities to extreme environmental conditions.

  15. Radiation-induced changes in late effects and in developmental capacities of exposed artemia cysts.

    PubMed

    Gaubin, Y; Pianezzi, B; Planel, H

    1985-10-14

    Artemia dry cysts from a Californian bisexual strain used in several space experiments were irradiated with 60Co gamma rays. The three cyst populations experimented could be differentiated according to their development and survival rates. The variations observed for both of these criteria were related to the age of the cysts and the selection technique. The study of radiosensitivity based on LD50 value showed that the highest radiosensitivity differences were related to the cyst selection technique and not to the age. Furthermore, the three cyst populations showed that radio-induced lethal effects were enhanced, or appeared with time, namely following the delay between irradiation and the cyst development study. The observation of late effects after irradiations or after space flights show the difficulties encountered in assessing radiative risks during long duration space flights.

  16. Can Artemia Hatching Assay Be a (Sensitive) Alternative Tool to Acute Toxicity Test?

    PubMed

    Rotini, A; Manfra, L; Canepa, S; Tornambè, A; Migliore, L

    2015-12-01

    Artemia sp. is extensively used in ecotoxicity testing, despite criticisms inherent to both acute and long-term tests. Alternative endpoints and procedures should be considered to support the use of this biological model. The hatching process comprises several developmental steps and the cyst hatchability seems acceptable as endpoint criterion. In this study, we assessed the reliability of the hatching assay on A. franciscana by comparing with acute and long-term mortality tests, using two chemicals: Diethylene Glycol (DEG), Sodium Dodecyl Sulphate (SDS). Both DEG and SDS tests demonstrated a dose dependent hatching inhibition. The hatching test resulted more sensitive than acute mortality test and less sensitive than the long-term one. Results demonstrate the reliability and high sensitivity of this hatching assay on a short time lag and support its useful application in first-tier risk assessment procedures.

  17. Interactive effect of selenium and mercury on development and mortality of brine shrimp, Artemia sp.

    SciTech Connect

    Forsythe, B.L. II; Bailey, F.C.; Klaine, S.J.

    1994-12-31

    The interactions between organic mercury and selenium derivatives are well documented. Inorganic mercury has been shown to have a deleterious effect on the development of brine shrimp, Artemia franciscana while selenate has no effect. In this study, concentrations as low as 0.1 mg/l Hg (as Hg(NO{sub 3})2) slowed the rate of development. Selenate concentrations ranging from 0.1 to 5.0 mg/l as Se decreased the effect of Hg on brine shrimp developmental rate. Both selenate and inorganic mercury alone produced a dose-response with respect to nauplii mortality. Preliminary data suggest that combinations of selenate and inorganic mercury act antagonistically to lower this mortality.

  18. Behavior of Settling Marine Larvae in Flow

    NASA Astrophysics Data System (ADS)

    Hernandez, J.; Koehl, M. A.

    2012-12-01

    Many bottom-dwelling marine animals produce microscopic larvae that are dispersed by ambient water currents. These larvae can only recruit to habitats on which they have landed if they can resist being washed away by ambient water flow. We found that larvae on marine surfaces do not experience steady water flow, but rather are exposed to brief pulses of water movement as turbulent eddies sweep across them. We made video recordings of larvae of the tube worm, Hydroides elegans, (important members of the community of organisms growing on docks and ships) on surfaces subjected to measured realistic flow pulses to study factors that might affect their dislodgement from surfaces in nature. We found that the response of a larva of H. elegans to a realistic pulse of water flow depended on its behavior at the time of the pulse and on its recent history of exposure to flow pulses, and that stationary larvae were less likely than locomoting larvae to be blown away when hit by the first pulse of water flow.; ;

  19. Hyperparasitism of mosquitoes by water mite larvae.

    PubMed

    Werblow, Antje; Martin, Peter; Dörge, Dorian D; Koch, Lisa K; Mehlhorn, Heinz; Melaun, Christian; Klimpel, Sven

    2015-07-01

    Hyperparasitism of ectoparasitic water mite larvae on mosquitoes is still a neglected relationship and was investigated only in a few studies. We analysed 2313 female mosquitoes from six different sampling localities with regard to their degree of parasitism with water mite larvae. In total, we found 38 mosquito individuals parasitized by 93 water mite larvae, ranging from 1 to 12 larvae per mosquito. Water mite larvae detected are members of the two species Parathyas cf. barbigera (n = 92) and Arrenurus cf. globator (n = 1). Out of the analysed mosquitoes, individuals out of the species Aedes vexans, Anopheles claviger, Ochlerotatus communis, the Ochlerotatus cantans/annulipes group, Ochlerotatus cataphylla and Ochlerotatus sticticus were tested to be parasitized by water mite larvae. The highest prevalence was found within the species Oc. cataphylla (28.6 %) and Oc. cantans/annulipes (21.7 %). No water mite larvae were found, e.g. on individuals of Aedes cinereus, Coquillettidia richiardii, the Culex pipiens/torrentium group, Ochlerotatus caspius, Ochlerotatus dorsalis or Ochlerotatus punctor. All of the attachment sites were located between the neck and abdomen with the ventral thorax site being the most frequent one.

  20. PESTICIDES AND THEIR METABOLITES IN THE HOMES AND URINE OF FARMWORKER CHILDREN LIVING IN THE SALINAS VALLEY, CA

    EPA Science Inventory

    This paper describes a study to test field methods for characterizing pesticide exposures to 20 farmworker children aged 5-27 months old living in the Salinas Valley of Monterey County, California. Methods for collecting house dust, indoor and outdoor air, dislodgeable residues ...

  1. Up-regulation of photoprotection and PSII-repair gene expression by irradiance in the unicellular green alga Dunaliella salina.

    PubMed

    Park, Seunghye; Polle, Juergen E W; Melis, Anastasios; Lee, Taek Kyun; Jin, Eonseon

    2006-01-01

    The unicellular green alga Dunaliella salina is an attractive model organism for studying photoacclimation responses and the photosystem II (PSII) damage and repair process in the photosynthetic apparatus. Irradiance during cell growth defines both the photoacclimation and the PSII repair status of the cells. To identify genes specific to these processes, a cDNA library was created from irradiance-stressed D. salina. From the cDNA library, 1112 randomly selected expressed sequence tags (ESTs) were analyzed. Because ESTs constitute the expressed part of the genome, the strategy of randomly sequencing cDNA clones at their 5'-ends allowed us to obtain information about the transcript level of numerous genes in light-stressed D. salina. The results of a BLASTX search performed on the obtained total set of ESTs showed that approximately 1% of the ESTs could be assigned to genes coding for proteins that are known to be up-regulated in response to high-light stress. Specifically, after 48 h of high-light exposure of the cells, an increase in the expression level of antioxidant genes, such as Fe-SOD and APX, was observed, as well as elevated levels of the Cbr transcript, a light-harvesting Chl-protein homolog. Further, the ATP-dependent Clp protease gene was also up-regulated in D. salina cells after 48 h of exposure to high light. The results provide initial insight into the global gene regulation process in response to irradiance.

  2. Effect of outdoor conditions on Nannochloropsis salina cultivation in artificial seawater using nutrients from anaerobic digestion effluent.

    PubMed

    Sheets, Johnathon P; Ge, Xumeng; Park, Stephen Y; Li, Yebo

    2014-01-01

    The effects of simulated outdoor seasonal climatic conditions on Nannochloropsis salina (N. salina) grown using nutrients from anaerobic digestion (AD) effluent were evaluated in this study. Under various light exposure (LE) and temperature (10-30 °C) conditions, N. salina specific growth rate (μ) was strongly affected by LE. Light availability (LA) was observed to be crucial for biomass production, with μ values of 0.038±0.013 d(-1), 0.093±0.013 d(-1), and 0.151±0.021 d(-1) for 6-h, 12-h, and 24-h LA conditions, respectively. Temperature (10-25 °C) was not significant in affecting the light dependent growth coefficient (μ/LE), indicating the suitability of culturing this strain in the Ohio climate. Cultures exposed to low illumination had significantly higher unsaturated fatty acid content than those under high illumination, with nearly 29% higher eicosapentaenoic acid (C20:5) content. Using LE and light attenuation resulted in adequate prediction of N. salina growth in a 1000 L open raceway pond.

  3. Cutaneous Larva Migrans in Early Infancy

    PubMed Central

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

    2015-01-01

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

  4. Characterization of PHB1 and Its Role in Mitochondrial Maturation and Yolk Platelet Degradation during Development of Artemia Embryos

    PubMed Central

    Ye, Xiang; Zhao, Yang; Zhao, Ling-Ling; Sun, Yu-Xia; Yang, Jin-Shu; Yang, Wei-Jun

    2014-01-01

    Background To cope with harsh environments, crustaceans such as Artemia produce diapause gastrula embryos (cysts) with suppressed metabolism. Metabolism and development resume during post-diapause development, but the mechanism behind these cellular events remains largely unknown. Principal Finding Our study investigated the role of prohibitin 1 (PHB1) in metabolic reinitiation during post-diapause development. We found that PHB1 was developmentally regulated via changes in phosphorylation status and localization. Results from RNA interference experiments demonstrated PHB1 to be critical for mitochondrial maturation and yolk degradation during development. In addition, PHB1 was present in yolk platelets, and it underwent ubiquitin-mediated degradation during the proteolysis of yolk protein. Conclusions/Significance PHB1 has an indispensable role in coordinating mitochondrial maturation and yolk platelet degradation during development in Artemia. This novel function of PHB1 provides new clues to comprehend the roles of PHB1 in metabolism and development. PMID:25310573

  5. Results on artemia cysts, lettuce and tobacco seeds in the Biobloc 4 experiment flown aboard the Soviet biosatellite Cosmos 1129

    SciTech Connect

    Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.

    1983-01-01

    The effects of space flight factors, in particular the heavy ion component of cosmic rays, on dormant stages of life forms were investigated as part of the Biobloc 4 experiment flown aboard the Cosmos 1129 biosatellite. Artemia cysts and seeds of tobacco and lettuce plants were placed in tubes and in monolayers sandwiched between layers of visual particle track detectors. Although Artemia cysts exposed in the dry state did not differ from ground controls, hydrated cysts exhibited a slight decrease in hatchability and reduced (C-14)O2 incorporation and protein and nucleic acid synthesis. For cysts held in the monolayers, hits by HZE particles were observed to stimulate emergence, hatching and survival. Higher proportions of chromosomal aberrations were found in lettuce seeds hit by HZE particles, while space flight produced a stimulatory effect on both germination rate and abnormality frequency in both hit and nonhit tobacco seeds. 9 references.

  6. Results on Artemia cysts, lettuce and tobacco seeds in the biobloc 4 experiment flown aboard the Soviet biosatellite Cosmos 1129

    NASA Astrophysics Data System (ADS)

    Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.; Delpoux, M.; Clegg, J.; Kovalev, E. E.; Nevzgodina, L. V.; Maximova, E. N.; Miller, A. T.

    Artemia cysts, lettuce and tobacco seeds were flown aboard the Cosmos 1129 for 19 days. A correlative method was used in order to determine the passage of cosmic heavy ions (HZE particles) through the biological test objects. This space flight resulted in a decrease on hatchability, nucleic acid and protein synthesis in hydrated Artemia cysts. HZE particle effects on plant cellular chromosomes are confirmed. In tobacco seeds, a stimulating effect on germination rate and a higher frequency of abnormalities were observed. Dormant biological objects are a very suitable material to study cosmic ray effects: these objects can be arranged in monolayers and sandwiched between visual track detectors in order to determine the passage of the cosmic heavy ions (HZE particles). On the other hand this method allows us to study effects of microgravity and those of the protonic component of cosmic rays in the objects not hit by the HZE particles.

  7. TIME management by medicinal larvae.

    PubMed

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

    2016-08-01

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

  8. Lethal infection thresholds of Paenibacillus larvae for honeybee drone and worker larvae (Apis mellifera).

    PubMed

    Behrens, Dieter; Forsgren, Eva; Fries, Ingemar; Moritz, Robin F A

    2010-10-01

    We compared the mortality of honeybee (Apis mellifera) drone and worker larvae from a single queen under controlled in vitro conditions following infection with Paenibacillus larvae, a bacterium causing the brood disease American Foulbrood (AFB). We also determined absolute P. larvae cell numbers and lethal titres in deceased individuals of both sexes up to 8 days post infection using quantitative real-time PCR (qPCR). Our results show that in drones the onset of infection induced mortality is delayed by 1 day, the cumulative mortality is reduced by 10% and P. larvae cell numbers are higher than in worker larvae. Since differences in bacterial cell titres between sexes can be explained by differences in body size, larval size appears to be a key parameter for a lethal threshold in AFB tolerance. Both means and variances for lethal thresholds are similar for drone and worker larvae suggesting that drone resistance phenotypes resemble those of related workers.

  9. Study of model systems to test the potential function of Artemia group 1 late embryogenesis abundant (LEA) proteins.

    PubMed

    Warner, Alden H; Guo, Zhi-hao; Moshi, Sandra; Hudson, John W; Kozarova, Anna

    2016-01-01

    Embryos of the brine shrimp, Artemia franciscana, are genetically programmed to develop either ovoviparously or oviparously depending on environmental conditions. Shortly upon their release from the female, oviparous embryos enter diapause during which time they undergo major metabolic rate depression while simultaneously synthesize proteins that permit them to tolerate a wide range of stressful environmental events including prolonged periods of desiccation, freezing, and anoxia. Among the known stress-related proteins that accumulate in embryos entering diapause are the late embryogenesis abundant (LEA) proteins. This large group of intrinsically disordered proteins has been proposed to act as molecular shields or chaperones of macromolecules which are otherwise intolerant to harsh conditions associated with diapause. In this research, we used two model systems to study the potential function of the group 1 LEA proteins from Artemia. Expression of the Artemia group 1 gene (AfrLEA-1) in Escherichia coli inhibited growth in proportion to the number of 20-mer amino acid motifs expressed. As well, clones of E. coli, transformed with the AfrLEA-1 gene, expressed multiple bands of LEA proteins, either intrinsically or upon induction with isopropyl-β-thiogalactoside (IPTG), in a vector-specific manner. Expression of AfrLEA-1 in E. coli did not overcome the inhibitory effects of high concentrations of NaCl and KCl but modulated growth inhibition resulting from high concentrations of sorbitol in the growth medium. In contrast, expression of the AfrLEA-1 gene in Saccharomyces cerevisiae did not alter the growth kinetics or permit yeast to tolerate high concentrations of NaCl, KCl, or sorbitol. However, expression of AfrLEA-1 in yeast improved its tolerance to drying (desiccation) and freezing. Under our experimental conditions, both E. coli and S. cerevisiae appear to be potentially suitable hosts to study the function of Artemia group 1 LEA proteins under environmentally

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

    PubMed

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

    2006-08-01

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

  11. Rearing Chrysoperla externa Larvae on Artificial Diets.

    PubMed

    Bezerra, C E S; Amaral, B B; Souza, B

    2017-02-01

    We tested three artificial diets for rearing larvae of Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae), aiming at reducing the production costs of this predator. Two of the diets come from studies with other species of lacewings, and the third is a modification described in this paper. All diets were based on animal protein and were supplied to 2nd and 3rd instar larvae, whereas 1st instar larvae received eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae). We evaluated the preimaginal duration and survival, adult size, longevity and fecundity, egg hatchability, and predatory capacity of larvae produced. The performance of the diets was followed for seven generations. The diet we describe showed to be the best among the artificial diets tested. Our results show that C. externa can be successfully reared on artificial diets during second and third instars, reducing in 90% the dependency on eggs of A. kuehniella.

  12. Multiple {gamma}-glutamylation: A novel type of post-translational modification in a diapausing Artemia cyst protein

    SciTech Connect

    Hasegawa, Mai; Ikeda, Yuka; Kanzawa, Hideaki; Sakamoto, Mika; Goto, Mina; Tsunasawa, Susumu; Uchiumi, Toshio; Odani, Shoji

    2010-03-26

    A highly hydrophilic, glutamate-rich protein was identified in the aqueous phenol extract from the cytosolic fraction of brine shrimp (Artemia franciscana) diapausing cysts and termed Artemia phenol soluble protein (PSP). Mass spectrometric analysis revealed the presence of many protein peaks around m/z 11,000, separated by 129 atomic mass units; this value corresponds to that of glutamate, which is strongly suggestive of heterogeneous polyglutamylation. Polyglutamylation has long been known as the functionally important post-translational modification of tubulins, which carry poly(L-glutamic acid) chains of heterogeneous length branching off from the main chain at the {gamma}-carboxy groups of a few specific glutamate residues. In Artemia PSP, however, Edman degradation of enzymatic peptides revealed that at least 13, and presumably 16, glutamate residues were modified by the attachment of a single L-glutamate, representing a hitherto undescribed type of post-translational modification: namely, multiple {gamma}-glutamylation or the addition of a large number of glutamate residues along the polypeptide chain. Although biological significance of PSP and its modification is yet to be established, suppression of in vitro thermal aggregation of lactate dehydrogenase by glutamylated PSP was observed.

  13. Shell-bound iron dependant nitric oxide synthesis in encysted Artemia parthenogenetica embryos during hydrogen peroxide exposure.

    PubMed

    Veeramani, Sivaram; Baskaralingam, Vaseeharan

    2011-12-01

    Artemia is a tiny marine crustacean, serves as an excellent tool in both basic and applied aspects of stress biology research. In the current manuscript, we report that Artemia parthenogenetica embryos (cysts), in diapause stage, undergo iron transition changes when exposed to chemical diapause deactivation stimulus (hydrogen peroxide). X-ray surface analysis of A. parthenogenetica embryos exposed to H(2)O(2) showed significant transitional changes in iron, as seen in cyst cross-sections. Electron paramagnetic resonance study revealed that upon H(2)O(2) exposure, increased nitric oxide (NO) production was observed in non-decapsulated cysts (ND), but not in decapsulated cysts (DC) (shell-removed cysts). Spin trapping studies also showed an increase in hydroxyl radical formation in NDs exposed to H(2)O(2) through Fenton-like reaction. On the contrary, exposure of DCs to H(2)O(2) did not induce hydroxyl radical formation. Taken together, results from the present study indicate a key role of cyst shell-bound iron and reactive oxygen species on successful diapause termination in eukaryotic extremophile animal model, such as Artemia.

  14. Salt sensitivity of the morphometry of Artemia franciscana during development: a demonstration of 3D critical windows.

    PubMed

    Mueller, Casey A; Willis, Eric; Burggren, Warren W

    2016-02-01

    A 3D conceptual framework of 'critical windows' was used to examine whether the morphometry of Artemia franciscana is altered by salinity exposure during certain key periods of development. Artemia franciscana were hatched at 20 ppt (designated control salinity) and were then exposed to 10, 30, 40 or 50 ppt either chronically (days 1-15) or only on days 1-6, 7-9, 10-12 or 13-15. On day 15, maturity was assessed and morphometric characteristics, including mass, total body length, tail length and width, length of the third swimming appendage and eye diameter, were measured. Maturation and morphometry on day 15 were influenced by the exposure window and salinity dose. Artemia franciscana were generally larger following exposure to 10 and 40 ppt during days 1-6 and 7-9 when compared with days 10-12 and 13-15, in part due to a higher percentage of mature individuals. Exposure to different salinities on days 1-6 produced the greatest differences in morphometry, and thus this appears to be a period in development when A. franciscana is particularly sensitive to salinity. Viewing the developmental window as three-dimensional allowed more effective visualization of the complex interactions between exposure window, stressor dose and the magnitude of morphometric changes in A. franciscana.

  15. Activity of R(+) Limonene Against Anisakis Larvae

    PubMed Central

    Muscolino, Daniele; Panebianco, Felice; Patania, Andrea; Benianti, Chiara; Ziino, Graziella; Giuffrida, Alessandro

    2015-01-01

    The aim of this work is to evaluate the activity of R(+) limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showed a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+) limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status. PMID:27800423

  16. A new simple method with high precision for determining the toxicity of antifouling paints on brine shrimp larvae (Artemia): first results.

    PubMed

    Castritsi-Catharios, J; Bourdaniotis, N; Persoone, G

    2007-04-01

    The use of antifouling paints is the only truly effective method for the protection of underwater structures from the development of fouling organisms. In the present study, the surface to volume concept constitutes the basis for the development of a new and improved method for determining the toxicity of antifouling paints on marine organisms. Particular emphasis is placed on the attainment of a standardized uniformity of coated surfaces. Failure to control the thickness of the coat of paint in previous studies of this type, has led to inaccurate evaluation of the relative toxicity of samples. Herein, an attempt is made to solve this problem using a simple technique which gives completely uniform and smooth surfaces. The effectiveness of this technique is assessed through two series of experiments using two different types of test containers: 50 ml modified syringes and 7 ml multiwells. The results of the toxicity experiments follow a normal distribution around the average value which allows to consider these values as reliable for comparison of the level of toxic effect detected with the two types of test containers. The mean lethal concentration L(S/V)(50) in the test series conducted in the multiwells (20.38 mm(2)ml(-1)) does not differ significantly from that obtained in the test series using modified syringes (20.065 mm(2)ml(-1)). It can thus be concluded from this preliminary study that the new method and the two different ways of exposing the test organisms to the antifouling paints and their leachates gave reliable and replicable results.

  17. Assessment of benthic changes during 20 years of monitoring the Mexican Salina Cruz Bay.

    PubMed

    González-Macías, C; Schifter, I; Lluch-Cota, D B; Méndez-Rodríguez, L; Hernández-Vázquez, S

    2009-02-01

    In this work a non-parametric multivariate analysis was used to assess the impact of metals and organic compounds in the macro infaunal component of the mollusks benthic community using surface sediment data from several monitoring programs collected over 20 years in Salina Cruz Bay, Mexico. The data for benthic mollusks community characteristics (richness, abundance and diversity) were linked to multivariate environmental patterns, using the Alternating Conditional Expectations method to correlate the biological measurements of the mollusk community with the physicochemical properties of water and sediments. Mollusks community variation is related to environmental characteristics as well as lead content. Surface deposit feeders are increasing their relative density, while subsurface deposit feeders are decreasing with respect to time, these last are expected to be more related with sediment and more affected then by its quality. However gastropods with predatory carnivore as well as chemosymbiotic deposit feeder bivalves have maintained their relative densities along time.

  18. Environmental assessment of aromatic hydrocarbons-contaminated sediments of the Mexican Salina Cuz Bay.

    PubMed

    González-Macías, C; Schifter, I; Lluch-Cota, D B; Méndez-Rodríguez, L; Hernández-Vázquez, S

    2007-10-01

    Concentrations of total aromatic hydrocarbons and extractable organic matter in the water column and sediment were determined in samples collected in the course of the last 20 years from the Salina Cruz Harbor, México, to assess the degree of organic contamination. In sediments, organic compounds accumulate in shallow areas mostly associated with extractable organic matter and fine fractions. Calculated geocumulation index and enrichment factors suggest that contamination could be derived from anthropogenic activities attributed to harbor and ship scrapping activities, as well as transboundary source. Concentration of total aromatic hydrocarbons (as chrysene equivalents) ranged from 0.01 to 534 microg l(-1) in water, and from 0.10 to 2,160 microg g(-1) in sediments. Total aromatic concentration of 5 microg g(-1) is proposed as background concentration.

  19. Altered lipid accumulation in Nannochloropsis salina CCAP849/3 following EMS and UV induced mutagenesis

    PubMed Central

    Beacham, T.A.; Macia, V. Mora; Rooks, P.; White, D.A.; Ali, S.T.

    2015-01-01

    Microalgae have potential as a chemical feed stock in a range of industrial applications. Nannochloropsis salina was subject to EMS mutagenesis and the highest lipid containing cells selected using fluorescence-activated cell sorting. Assessment of growth, lipid content and fatty acid composition identified mutant strains displaying a range of altered traits including changes in the PUFA content and a total FAME increase of up to 156% that of the wild type strain. Combined with a reduction in growth this demonstrated a productivity increase of up to 76%. Following UV mutagenesis, lipid accumulation of the mutant cultures was elevated to more than 3 fold that of the wild type strain, however reduced growth rates resulted in a reduction in overall productivity. Changes observed are indicative of alterations to the regulation of the omega 6 Kennedy pathway. The importance of these variations in physiology for industrial applications such as biofuel production is discussed. PMID:26753128

  20. Salimyxins and enhygrolides: antibiotic, sponge-related metabolites from the obligate marine myxobacterium Enhygromyxa salina.

    PubMed

    Felder, Stephan; Kehraus, Stefan; Neu, Edith; Bierbaum, Gabriele; Schäberle, Till F; König, Gabriele M

    2013-07-22

    Unlike their terrestrial counterparts, marine myxobacteria are hardly investigated for their secondary metabolites. This study describes three new compounds (1-3), named salimyxins and enhygrolides, obtained from the obligate marine myxobacterium Enhygromyxa salina. These are the first natural products obtained from Enhygromyxa species. Their structures were elucidated by spectroscopic analysis, including NMR and CD spectroscopy. Enhygrolides are closely related to the nostoclides, which were initially isolated from a cyanobacterium of the genus Nostoc. The salimyxins, representing structurally most unusual degraded sterols, are close to identical to demethylincisterol from the sponge Homaxinella sp. Salimyxin B and enhygrolide A inhibit the growth of the Gram-positive bacterium Arthrobacter cristallopoietes (MIC salimyxin B, 8 μg mL⁻¹; enhygrolide A, 4 μg mL⁻¹).

  1. Analysis of the Physiological and Molecular Responses of Dunaliella salina to Macronutrient Deprivation

    PubMed Central

    Lv, Hexin; Cui, Xianggan; Wahid, Fazli; Xia, Feng; Zhong, Cheng; Jia, Shiru

    2016-01-01

    The halotolerant chlorophyte Dunaliella salina can accumulate up to 10% of its dry weight as β-carotene in chloroplasts when subjected to adverse conditions, including nutrient deprivation. However, the mechanisms of carotenoid biosynthesis are poorly understood. Here, the physiological and molecular responses to the deprivation of nitrogen (-N), sulfur (-S), phosphorus (-P) and different combinations of those nutrients (-N-P, -N-S, -P-S and -N-P-S) were compared to gain insights into the underlying regulatory mechanisms of carotenoid biosynthesis. The results showed that both the growth and photosynthetic rates of cells were decreased during nutrient deprivation, accompanied by lipid globule accumulation and reduced chlorophyll levels. The SOD and CAT activities of the cells were altered during nutrient deprivation, but their responses were different. The total carotenoid contents of cells subjected to multiple nutrient deprivation were higher than those of cells subjected to single nutrient deprivation and non-stressed cells. The β-carotene contents of cells subjected to -N-P, -N-S and -N-P-S were higher than those of cells subjected to single nutrient deprivation. Cells subjected to sulfur deprivation accumulated more lutein than cells subjected to nitrogen and phosphorous deprivation. In contrast, no cumulative effects of nutrient deprivation on the transcription of genes in the carotenogenic pathway were observed because MEP and carotenogenic pathway genes were up-regulated during single nutrient deprivation but were downregulated during multiple nutrient deprivation. Therefore, we proposed that the carotenoid biosynthesis pathway of D. salina is regulated at both the transcriptional and posttranscriptional levels and that a complex crosstalk occurs at the physiological and molecular levels in response to the deprivation of different nutrients. PMID:27023397

  2. Bioflocculation of the oceanic microalga Dunaliella salina by the bloom-forming dinoflagellate Heterocapsa circularisquama, and its effect on biodiesel properties of the biomass.

    PubMed

    Cho, Kichul; Hur, Sung-Pyo; Lee, Chi-Heon; Ko, Kyungjun; Lee, Yeon-Ji; Kim, Kil-Nam; Kim, Moo-Sang; Chung, Young-Ho; Kim, Daekyung; Oda, Tatsuya

    2016-02-01

    The aim of this work was to evaluate the flocculation by the dinoflagellate Heterocapsa circularisquama as a means for harvesting three Chlorophyta species, Chlorella vulgaris, Nannochloropsis granulata, and Dunaliella salina. Relative fluorescence of D. salina culture significantly decreased along with 9.3-fold increased flocculation activity within 24 h when mixed with H. circularisquama. Lipid content of bioflocculated D. salina increased about 40%, while fatty acid methyl ester (FAME) profiles exhibited higher levels of C16:0, C18:0, and C18:1, compared to harvest by centrifugation, suggesting higher energy content. Furthermore, bioflocculated D. salina biomass had more suitable biodiesel properties relative to both EN14214 and ASTMD6751, with a cetane number of 49.0 and an iodine value of 95.9. These results suggest that H. circularisquama-induced bioflocculation is applicable for the sustainable and qualitative production of algal biodiesel.

  3. The carotenogenesis pathway via the isoprenoid-beta-carotene interference approach in a new strain of Dunaliella salina isolated from Baja California Mexico.

    PubMed

    Paniagua-Michel, J; Capa-Robles, Willian; Olmos-Soto, Jorge; Gutierrez-Millan, Luis Enrique

    2009-01-01

    D. salina is one of the recognized natural sources to produce beta-carotene, and an useful model for studying the role of inhibitors and enhancers of carotenogenesis. However there is little information in D. salina regarding whether the isoprenoid substrate can be influenced by stress factors (carotenogenic) or selective inhibitors which in turn may further contribute to elucidate the early steps of carotenogenesis and biosynthesis of beta-carotene. In this study, Dunaliella salina (BC02) isolated from La Salina BC Mexico, was subjected to the method of isoprenoids-beta-carotene interference in order to promote the interruption or accumulation of the programmed biosynthesis of carotenoids. When Carotenogenic and non-carotenogenic cells of D. salina BC02 were grown under photoautotrophic growth conditions in the presence of 200 microM fosmidomycin, carotenogenesis and the synthesis of beta-carotene were interrupted after two days in cultured D. salina cells. This result is an indirect consequence of the inhibition of the synthesis of isoprenoids and activity of the recombinant DXR enzyme thereby preventing the conversion of 1-deoxy-D-xylulose 5-phosphate (DXP) to 2-C-methyl-D-erythritol (MEP) and consequently interrupts the early steps of carotenogenesis in D. salina. The effect at the level of proteins and RNA was not evident. Mevinolin treated D. salina cells exhibited carotenogenesis and beta-carotene levels very similar to those of control cell cultures indicating that mevinolin not pursued any indirect action in the biosynthesis of isoprenoids and had no effect at the level of the HMG-CoA reductase, the key enzyme of the Ac/MVA pathway.

  4. The Carotenogenesis Pathway via the Isoprenoid-β-carotene Interference Approach in a New Strain of Dunaliella salina Isolated from Baja California Mexico

    PubMed Central

    Paniagua-Michel, J.; Capa-Robles, Willian; Olmos-Soto, Jorge; Gutierrez-Millan, Luis Enrique

    2009-01-01

    D. salina is one of the recognized natural sources to produce β-carotene, and an useful model for studying the role of inhibitors and enhancers of carotenogenesis. However there is little information in D. salina regarding whether the isoprenoid substrate can be influenced by stress factors (carotenogenic) or selective inhibitors which in turn may further contribute to elucidate the early steps of carotenogenesis and biosynthesis of β-carotene. In this study, Dunaliella salina (BC02) isolated from La Salina BC Mexico, was subjected to the method of isoprenoids-β-carotene interference in order to promote the interruption or accumulation of the programmed biosynthesis of carotenoids. When Carotenogenic and non-carotenogenic cells of D. salina BC02 were grown under photoautotrophic growth conditions in the presence of 200 µM fosmidomycin, carotenogenesis and the synthesis of β-carotene were interrupted after two days in cultured D. salina cells. This result is an indirect consequence of the inhibition of the synthesis of isoprenoids and activity of the recombinant DXR enzyme thereby preventing the conversion of 1-deoxy-D-xylulose 5-phosphate (DXP) to 2-C-methyl-D-erythritol (MEP) and consequently interrupts the early steps of carotenogenesis in D. salina. The effect at the level of proteins and RNA was not evident. Mevinolin treated D. salina cells exhibited carotenogenesis and β-carotene levels very similar to those of control cell cultures indicating that mevinolin not pursued any indirect action in the biosynthesis of isoprenoids and had no effect at the level of the HMG-CoA reductase, the key enzyme of the Ac/MVA pathway. PMID:19370170

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and...

  6. Chironomidae bloodworms larvae as aquatic amphibian food.

    PubMed

    Fard, Mojdeh Sharifian; Pasmans, Frank; Adriaensen, Connie; Laing, Gijs Du; Janssens, Geert Paul Jules; Martel, An

    2014-01-01

    Different species of chironomids larvae (Diptera: Chironomidae) so-called bloodworms are widely distributed in the sediments of all types of freshwater habitats and considered as an important food source for amphibians. In our study, three species of Chironomidae (Baeotendipes noctivagus, Benthalia dissidens, and Chironomus riparius) were identified in 23 samples of larvae from Belgium, Poland, Russia, and Ukraine provided by a distributor in Belgium. We evaluated the suitability of these samples as amphibian food based on four different aspects: the likelihood of amphibian pathogens spreading, risk of heavy metal accumulation in amphibians, nutritive value, and risk of spreading of zoonotic bacteria (Salmonella, Campylobacter, and ESBL producing Enterobacteriaceae). We found neither zoonotic bacteria nor the amphibian pathogens Ranavirus and Batrachochytrium dendrobatidis in these samples. Our data showed that among the five heavy metals tested (Hg, Cu, Cd, Pb, and Zn), the excess level of Pb in two samples and low content of Zn in four samples implicated potential risk of Pb accumulation and Zn inadequacy. Proximate nutritional analysis revealed that, chironomidae larvae are consistently high in protein but more variable in lipid content. Accordingly, variations in the lipid: protein ratio can affect the amount and pathway of energy supply to the amphibians. Our study indicated although environmentally-collected chironomids larvae may not be vectors of specific pathogens, they can be associated with nutritional imbalances and may also result in Pb bioaccumulation and Zn inadequacy in amphibians. Chironomidae larvae may thus not be recommended as single diet item for amphibians.

  7. Ventral nerve cord in Phoronopsis harmeri larvae.

    PubMed

    Temereva, Elena N

    2012-01-15

    The nervous system organization is considered a phylogenetically important character among metazoans. The phylum Phoronida is included in a supraphyletic taxon known as Lophotrochozoa. Many lophotrochozoans possess a metameric ventral nerve cord as adults or larvae. Phoronids do not exhibit external metamery either as larvae or as adults. The current study describes the ventral nerve cord in the young larva of Phoronopsis harmeri. This structure is apparent both in the serotonergic and FMRF-amidergic nervous system in young larvae. The ventral nerve cord extends from the mouth to the tentacular ridge. Both serotonergic and FMRF-amidergic components consist of two ventrolateral nerves, each with several unipolar neurons. The ventrolateral nerves connect to each other by means of thin repetitive transversal nerves ("commissures"). The abundance of neurons and nerves in the epidermis of the oral field of actinotrocha larva likely reflects the importance of this area in collection of food particles. The ventral nerve cords of the actinotrocha and the metatrochophore differ in their positions with respect to ciliated bands: the cord is located between the preoral and postoral ciliated bands in the actinotrocha but between the postoral ciliated band and telotroch in the metatrochophore. The presence of the ventral nerve cord, which contains repetitive elements (neurons and "commissures"), in the early development of P. harmeri may recapitulate some stages of nervous system development during phoronid phylogeny. The larval nervous system does not contain nervous centers under the tentacular ridge that can correlate with the catastrophic metamorphosis and unique body plan of phoronids.

  8. Effect of specific light supply rate on photosynthetic efficiency of Nannochloropsis salina in a continuous flat plate photobioreactor.

    PubMed

    Sforza, Eleonora; Calvaruso, Claudio; Meneghesso, Andrea; Morosinotto, Tomas; Bertucco, Alberto

    2015-10-01

    In this work, Nannochloropsis salina was cultivated in a continuous-flow flat-plate photobioreactor, working at different residence times and irradiations to study the effect of the specific light supply rate on biomass productivity and photosynthetic efficiency. Changes in residence times lead to different steady-state cell concentrations and specific growth rates. We observed that cultures at steady concentration were exposed to different values of light intensity per cell. This specific light supply rate was shown to affect the photosynthetic status of the cells, monitored by fluorescence measurements. High specific light supply rate can lead to saturation and photoinhibition phenomena if the biomass concentration is not optimized for the selected operating conditions. Energy balances were applied to quantify the biomass growth yield and maintenance requirements in N. salina cells.

  9. Molecular approaches for improving desiccation tolerance: Insights from the brine shrimp Artemia franciscana

    PubMed Central

    Hand, Steven C.; Menze, Michael A.

    2015-01-01

    Organisms inhabiting both aquatic and terrestrial ecosystems frequently are confronted with the problem of water loss for multiple reasons – exposure to hypersalinity, evaporative water loss, and restriction of intracellular water due to freezing of extracellular fluids. Seasonal desiccation can become severe and lead to the production of tolerant propagules and entry into the state of anhydrobiosis at various stages of the life cycle. Such is the case for gastrula-stage embryos of the brine shrimp, Artemia franciscana. Physiological and biochemical responses to desiccation are central for survival and are multifaceted. This review will evaluate the impact of multiple Late Embryogenesis Abundant (LEA) proteins originating from A. franciscana, together with the non-reducing sugar trehalose, on prevention of desiccation damage at multiple levels of biological organization. Survivorship of desiccation-sensitive cells during water stress can be improved by use of the above protective agents, coupled to metabolic preconditioning and rapid cell drying. However, obtaining long-term stability of cells in the dried state at room temperature has not been accomplished and will require continued efforts on both the physicochemical and biological fronts. PMID:25809151

  10. Thermal stability of Artemia HGPRT: effect of substrates on inactivation kinetics.

    PubMed

    Montero, C; Llorente, P; Argomaniz, L; Menendez, M

    1996-06-01

    Hypoxanthine-guanine phosphoribosyltransferase (HGPRT, E.C.2.4.2.8) from Artemia cysts exhibits maximum activity at 70 degrees C. Its thermal stability has been examined following enzymatic activity as a function of temperature. Cold-induced renaturation experiments of samples heated at increasing temperatures showed that reversibility of thermal inactivation depends on the incubation time and final temperature. Prolonged incubation of the thermoinactivated enzyme at 0 degree C did not afford any further increase of the catalytic activity at 37 degrees C. The complex substrate PRPP:Mg protects HGPRT from thermal inactivation. However, incubations with hypoxanthine rendered a less thermostable enzyme at any temperature tested. The irreversible inactivation of HGPRT proceeds in two exponential steps. The analysis of the apparent rate constants for the fast and the slow phases, lambda 1 and lambda 2 as per the Lumry and Eyring model suggests the existence of more than three states in the thermal denaturation pathway of the free enzyme. In the presence of PRPP:Mg the irreversible process follows a single exponential and proceeds very slowly below 70 degrees C. PRPP:Mg also protects the enzyme from inactivation by NEM and pCMB, suggesting that -SH groups may be in the vicinity of the active site.

  11. Structure of Artemia franciscana sarco/endoplasmic reticulum Ca-ATPase gene.

    PubMed

    Escalante, R; Sastre, L

    1994-04-29

    Genomic clones coding for the Artemia franciscana sarco(endo)plasmic reticulum Ca-ATPase have been isolated. The restriction map of the overlapping clones covers a region of 65 kilobases of DNA. Nucleotide sequence of mRNA coding regions shows that the gene is divided into 18 exons separated by 17 introns. Compared with the structure of the rabbit sarco(endo)plasmic reticulum Ca-ATPase 1 gene, 12 of the introns are in the same position, 8 introns present in the rabbit gene are absent from A. franciscana, 4 introns present in A. franciscana are not found in rabbit, and the position of 1 intron is shifted one base between both genes. Southern blot analysis strongly suggests that this is the only sarco(endo)plasmic reticulum Ca-ATPase gene present in A. franciscana. Primer extension and nuclease S1 protection experiments have shown the existence of two main regions of transcription initiation separated by 30 nucleotides. Transcription is initiated in both regions at two or three consecutive bases. A hexanucleotide that includes the initiation sites is repeated in both transcription initiation regions. The nucleotide sequence of the promoter region shows the existence of several putative regulatory sites, including some that are muscle-specific such as one CArG box, 3 MEF-2, and 8 putative binding sites for muscle transcription factors of the MyoD family.

  12. Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization

    PubMed Central

    Butler, Aodhán D.; Cunningham, John A.; Budd, Graham E.; Donoghue, Philip C. J.

    2015-01-01

    Exceptionally preserved fossils provide major insights into the evolutionary history of life. Microbial activity is thought to play a pivotal role in both the decay of organisms and the preservation of soft tissue in the fossil record, though this has been the subject of very little experimental investigation. To remedy this, we undertook an experimental study of the decay of the brine shrimp Artemia, examining the roles of autolysis, microbial activity, oxygen diffusion and reducing conditions. Our findings indicate that endogenous gut bacteria are the main factor controlling decay. Following gut wall rupture, but prior to cuticle failure, gut-derived microbes spread into the body cavity, consuming tissues and forming biofilms capable of mediating authigenic mineralization, that pseudomorph tissues and structures such as limbs and the haemocoel. These observations explain patterns observed in exceptionally preserved fossil arthropods. For example, guts are preserved relatively frequently, while preservation of other internal anatomy is rare. They also suggest that gut-derived microbes play a key role in the preservation of internal anatomy and that differential preservation between exceptional deposits might be because of factors that control autolysis and microbial activity. The findings also suggest that the evolution of a through gut and its bacterial microflora increased the potential for exceptional fossil preservation in bilaterians, providing one explanation for the extreme rarity of internal preservation in those animals that lack a through gut. PMID:25972468

  13. Environmental heat stress induces epigenetic transgenerational inheritance of robustness in parthenogenetic Artemia model.

    PubMed

    Norouzitallab, Parisa; Baruah, Kartik; Vandegehuchte, Michiel; Van Stappen, Gilbert; Catania, Francesco; Vanden Bussche, Julie; Vanhaecke, Lynn; Sorgeloos, Patrick; Bossier, Peter

    2014-08-01

    The notion that phenotypic traits emerging from environmental experiences are heritable remains under debate. However, the recent report of nonmendelian transgenerational epigenetic inheritance, i.e., the inheritance of traits not determined by the DNA sequence, might make such a phenomenon plausible. In our study, by carrying out common garden experiments, we could provide clear evidences that, on exposure to nonlethal heat shocks, a parental population of parthenogenetic (all female) Artemia (originating from one single female) experiences an increase in levels of Hsp70 production, tolerance toward lethal heat stress, and resistance against pathogenic Vibrio campbellii. Interestingly, these acquired phenotypic traits were transmitted to three successive generations, none of which were exposed to the parental stressor. This transgenerational inheritance of the acquired traits was associated with altered levels of global DNA methylation and acetylated histones H3 and H4 in the heat-shocked group compared to the control group, where both the parental and successive generations were reared at standard temperature. These results indicated that epigenetic mechanisms, such as global DNA methylation and histones H3 and H4 acetylation, have particular dynamics that are crucial in the heritability of the acquired adaptive phenotypic traits across generations.

  14. Segmental mismatch in crustacean appendages: the naupliar antennal exopod of Artemia (Crustacea, Branchiopoda, Anostraca).

    PubMed

    Maruzzo, Diego; Minelli, Alessandro; Fusco, Giuseppe

    2009-03-01

    Based on traditional techniques and confocal laser scanning microscopy for external morphology, and immunohistochemistry for the muscular system, we describe here the segmental features of the antennal exopod of Artemia nauplii. Two kinds of serial elements are present, i.e. setae (with cuticular folds at their base) and ringlets (serially arranged sclerites separated by joint-like cuticular folds not extending to form complete rings around the appendage). The two series are usually not in register. The cuticular folds of the setae and of the ringlets are also sites of intermediate insertions of the three exopod muscles: as the two tegumentary structures are discordant in periodicity, this is also mirrored in the pattern of muscle insertions on the two sides of the appendage. Similar cases of segmental mismatch are known for the trunk of several arthropods, but segmental mismatch along the appendages has received very little attention. The occurrence of segmental mismatch in the naupliar appendages of both extant and fossil crustaceans is reviewed and it is suggested here to be a primitive feature of the exopods of both second antennae and mandibles. Problems in the interpretation of morphological evidence are discussed, also in relation to development and evolution of segmentation of naupliar appendages.

  15. Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization.

    PubMed

    Butler, Aodhán D; Cunningham, John A; Budd, Graham E; Donoghue, Philip C J

    2015-06-07

    Exceptionally preserved fossils provide major insights into the evolutionary history of life. Microbial activity is thought to play a pivotal role in both the decay of organisms and the preservation of soft tissue in the fossil record, though this has been the subject of very little experimental investigation. To remedy this, we undertook an experimental study of the decay of the brine shrimp Artemia, examining the roles of autolysis, microbial activity, oxygen diffusion and reducing conditions. Our findings indicate that endogenous gut bacteria are the main factor controlling decay. Following gut wall rupture, but prior to cuticle failure, gut-derived microbes spread into the body cavity, consuming tissues and forming biofilms capable of mediating authigenic mineralization, that pseudomorph tissues and structures such as limbs and the haemocoel. These observations explain patterns observed in exceptionally preserved fossil arthropods. For example, guts are preserved relatively frequently, while preservation of other internal anatomy is rare. They also suggest that gut-derived microbes play a key role in the preservation of internal anatomy and that differential preservation between exceptional deposits might be because of factors that control autolysis and microbial activity. The findings also suggest that the evolution of a through gut and its bacterial microflora increased the potential for exceptional fossil preservation in bilaterians, providing one explanation for the extreme rarity of internal preservation in those animals that lack a through gut.

  16. Quantifying and predicting Drosophila larvae crawling phenotypes

    PubMed Central

    Günther, Maximilian N.; Nettesheim, Guilherme; Shubeita, George T.

    2016-01-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly’s power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer’s disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design. PMID:27323901

  17. Sensorimotor structure of Drosophila larva phototaxis.

    PubMed

    Kane, Elizabeth A; Gershow, Marc; Afonso, Bruno; Larderet, Ivan; Klein, Mason; Carter, Ashley R; de Bivort, Benjamin L; Sprecher, Simon G; Samuel, Aravinthan D T

    2013-10-01

    The avoidance of light by fly larvae is a classic paradigm for sensorimotor behavior. Here, we use behavioral assays and video microscopy to quantify the sensorimotor structure of phototaxis using the Drosophila larva. Larval locomotion is composed of sequences of runs (periods of forward movement) that are interrupted by abrupt turns, during which the larva pauses and sweeps its head back and forth, probing local light information to determine the direction of the successive run. All phototactic responses are mediated by the same set of sensorimotor transformations that require temporal processing of sensory inputs. Through functional imaging and genetic inactivation of specific neurons downstream of the sensory periphery, we have begun to map these sensorimotor circuits into the larval central brain. We find that specific sensorimotor pathways that govern distinct light-evoked responses begin to segregate at the first relay after the photosensory neurons.

  18. Sensorimotor structure of Drosophila larva phototaxis

    PubMed Central

    Kane, Elizabeth A.; Gershow, Marc; Afonso, Bruno; Larderet, Ivan; Klein, Mason; Carter, Ashley R.; de Bivort, Benjamin L.; Sprecher, Simon G.; Samuel, Aravinthan D. T.

    2013-01-01

    The avoidance of light by fly larvae is a classic paradigm for sensorimotor behavior. Here, we use behavioral assays and video microscopy to quantify the sensorimotor structure of phototaxis using the Drosophila larva. Larval locomotion is composed of sequences of runs (periods of forward movement) that are interrupted by abrupt turns, during which the larva pauses and sweeps its head back and forth, probing local light information to determine the direction of the successive run. All phototactic responses are mediated by the same set of sensorimotor transformations that require temporal processing of sensory inputs. Through functional imaging and genetic inactivation of specific neurons downstream of the sensory periphery, we have begun to map these sensorimotor circuits into the larval central brain. We find that specific sensorimotor pathways that govern distinct light-evoked responses begin to segregate at the first relay after the photosensory neurons. PMID:24043822

  19. Quantifying and predicting Drosophila larvae crawling phenotypes.

    PubMed

    Günther, Maximilian N; Nettesheim, Guilherme; Shubeita, George T

    2016-06-21

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly's power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer's disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design.

  20. Quantifying and predicting Drosophila larvae crawling phenotypes

    NASA Astrophysics Data System (ADS)

    Günther, Maximilian N.; Nettesheim, Guilherme; Shubeita, George T.

    2016-06-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly’s power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer’s disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design.

  1. Investigations of the effects of cosmic rays on Artemia cysts and tobacco seeds; results of Exobloc II experiment, flown aboard Biocosmos 1887.

    PubMed

    Gaubin, Y; Delpoux, M; Pianezzi, B; Gasset, G; Heilmann, C; Planel, H

    1990-01-01

    Artemia (Brine shrimp) cysts and tobacco seeds, dormant biological material devoid of metabolic activity, were flown aboard the Soviet Biocosmos 1887 in order to investigate the effects of cosmic rays. Artemia cysts and tobacco seeds were used in bulk or in monolayers sandwiched with track detectors. Biological and physical units were located outside and inside the spacecraft. Stacks included lead shielding in order to expose the objects to different doses of radiation. Total dosimetry was performed using thermoluminescent detectors. In spite of low levels of doses, the space flight resulted in a decrease in developmental capacity of Artemia cysts, and in a higher mutation rate in tobacco seeds. The more obvious responses occurred, in both cases, in biological objects exposed to the highest doses. These results are compared to those of previous space experiments.

  2. Colorimetric Evaluation of the Viability of the Microalga Dunaliella Salina as a Test Tool for Nanomaterial Toxicity.

    PubMed

    Golubev, Alexander A; Prilepskii, Artur Y; Dykman, Lev A; Khlebtsov, Nikolai G; Bogatyrev, Vladimir A

    2016-05-01

    A diagnostic test system was developed to determine the toxicity of nanomaterials to the saltwater microalga Dunaliella salina through evaluation of cell death and changes in the culture growth rate at various toxicant concentrations, providing LC50 and other toxicological metrics. The viability of cells was shown to decrease with decreasing chlorophyll absorption of red light by damaged cells. This correlation was confirmed by independent fluorescence microscopic measurements of live and dead cells in the population. Two standard colorless pollutants, hydrogen peroxide and formaldehyde, were used to validate the colorimetric method. The method's performance is exemplified with three Ag-containing preparations (Ag nitrate, Ag proteinate, and 20-nm Ag nanoparticles) and with cetyltrimethylammonium bromide (CTAB) mixed with colloidal 15-nm Au and 20-nm Ag nanoparticles. The toxicity of the Ag-containing preparations to D. salina decreased in the order Ag nitrate ≥ Ag proteinate ≫ colloidal Ag. The toxicity of colloidal Au-CTAB mixtures was found to depend mostly on the content of free CTAB. The toxicity of colloidal Ag increased substantially in the presence of CTAB. The results suggest that our D. salina-based colorimetric test system can be used for simple and rapid preliminary screening of the toxicity of different nanomaterials.

  3. Thermal maturation and petroleum source rocks in Forest City and Salina basins, mid-continent, U. S. A

    SciTech Connect

    Newell, K.D.; Watney, W.L.; Hatch, J.R.; Xiaozhong, G.

    1986-05-01

    Shales in the Middle Ordovician Simpson Group are probably the source rocks for a geochemically distinct group of lower pristane and low phytane oils produced along the axis of the Forest City basin, a shallow cratonic Paleozoic basin. These oils, termed Ordovician-type oils, occur in some fields in the southern portion of the adjacent Salina basin. Maturation modeling by time-temperature index (TTI) calculations indicate that maturation of both basins was minimal during the early Paleozoic. The rate of maturation significantly increased during the Pennsylvanian because of rapid regional subsidence in response to the downwarping of the nearby Anadarko basin. When estimated thicknesses of eroded Pennsylvanian, Permian, and Cretaceous strata are considered, both basins remain relatively shallow, with maximum basement burial probably not exceeding 2 km. According to maturation modeling and regional structure mapping, the axes of both basins should contain Simpson rocks in the early stages of oil generation. The probability of finding commercial accumulations of Ordovician-type oil along the northwest-southeast trending axis of the Salina basin will decrease in a northwestward direction because of (1) westward thinning of the Simpson Group, and (2) lesser maturation due to lower geothermal gradients and shallower paleoburial depths. The optimum localities for finding fields of Ordovician-type oil in the southern Salina basin will be in down-plunge closures on anticlines that have drainage areas near the basin axis.

  4. Incidence of ascaridoid larvae in Kuwaiti food fishes.

    PubMed

    Sey, O; Petter, A J

    1997-01-01

    Three hundred and six fish of 83 species were carefully examined in Kuwait during the period from October 1992 to September 1995 for ascaridoid larvae. Thirty-nine fishes (12.7%) belonging to 23 species were infected with 9 types of ascaridoid third-stage larvae: Anisakis simplex, Terranva spp, Contracaecum spp and 6 different types of Hysterothylacium spp (KA-KF). Hysterothylacium larvae (including all types) were found in all the infected fish except one (94.6%); Terranova larvae were found in 12 fishes (10 species, 56.1%); Anisakis simplex larvae occurred in 2 fishes (2 species, 8.6%) and Contracaecum spp larvae in one fish only.

  5. Predators induce cloning in echinoderm larvae.

    PubMed

    Vaughn, Dawn; Strathmann, Richard R

    2008-03-14

    Asexual propagation (cloning) is a widespread reproductive strategy of plants and animals. Although larval cloning is well documented in echinoderms, identified stimuli for cloning are limited to those associated with conditions favorable for growth and reproduction. Our research shows that larvae of the sand dollar Dendraster excentricus also clone in response to cues from predators. Predator-induced clones were smaller than uncloned larvae, suggesting an advantage against visual predators. Our results offer another ecological context for asexual reproduction: rapid size reduction as a defense.

  6. Simulated effects of ground-water management alternatives for the Salinas Valley, California

    USGS Publications Warehouse

    Yates, E.B.

    1988-01-01

    A two-dimensional digital groundwater flow model was developed to analyze the geohydrology of the groundwater basin in the Salinas Valley. The model was calibrated for steady-state and transient simulations by comparing simulated with measured or estimated inflows, outflows, and water levels for 1970-81. Preliminary estimates of hydraulic properties and some inflows and outflows were adjusted during model calibration. The simulated mean annual water budget for the basin was 559,500 acre-ft/yr each of outflow and inflow. Inflow components consisted of Salinas River recharge (38.3%), percolation of irrigation water (34.0%), small stream and Arroyo Seco recharge (20.9%), seawater intrusion (3.4%), and other sources (3.4%). Outflow components consisted of agricultural pumpage (91.5%), municipal pumpage (4.0%), and riparian phreatophyte evapotranspiration (4.5%). For the steady-state calibration, 70% of the simulated water levels were within 9 ft of measured water levels for 1970-81. A sensitivity analysis determined the overall stability of the model results. The model input variable that probably contributes most to the uncertainty of the results is the quantity of groundwater recharge contributed by irrigation-return flow to the unconfined aquifer. A 15% change in the estimate of this variable causes an 11% change in the simulated river-seepage rate and a 6% change in the simulated seawater intrusion rate. The calibrated model was used to investigate several water resources management alternatives. Projected pumpage increase at a rate of 1%/yr for 20 yr caused declines in mean annual water levels of 10 to 20 ft in some areas and an increase in seawater intrusion from 18,900 to 23 ,600 acre-ft/yr. Pumpage decreases in the coastal area decreased seawater intrusion more effectively than pumpage decreases farther inland. When pumpage was decreased uniformly throughout the valley, the decrease in seawater intrusion was only one-fourteenth the decrease in pumpage

  7. The effects of feeding with synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia on skin mucus immune responses, stress resistance, intestinal microbiota and performance of angelfish (Pterophyllum scalare).

    PubMed

    Azimirad, Mahmood; Meshkini, Saeed; Ahmadifard, Nasrollah; Hoseinifar, Seyed Hossein

    2016-07-01

    The aim of this study was to evaluate the effects of feeding on synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia franciscana on skin mucus immune responses, stress resistance, intestinal microbiota and growth performance of angelfish (Pterophyllum scalare). Three hundred and sixty fish with initial weight 3.2 ± 0.13 g were randomly divided into twelve aquaria (50 L) assigned to four groups in triplicates. Fish were fed for 7 weeks with dietary treatments, including treatment 1: feeding adult Artemia without enrichment (control group), treatment 2: feeding adult Artemia enriched with lyophilised probiotic P. acidilactici (700 mg L(-1)), 3: feeding adult Artemia enriched with prebiotic fructooligosaccharide (FOS) (100 mg L(-1)), group 4: feeding adult Artemia enriched with synbiotic (P. acidilactici (700 mg L(-1)) + FOS (100 mg L(-1))). Skin mucus immune responses (lysozyme activity, total Immunoglobulin and protease), stress resistance against environmental stress (acute decrease of temperature and increase salinity), intestinal microbiota as well as growth indices were measured at the end of feeding trial. Artemia enriched with synbiotic significantly improved growth performance compared to other treatments (P < 0.05). The highest weight gain and specific growth rate (SGR) was observed in synbiotic fed fish (P < 0.05). Compared to the other treatments, the population of lactic acid bacteria was significantly higher in the intestinal microbiota of fish fed synbiotic supplemented diet (P < 0.05). In the environmental stress challenge test, the maximum resistance to abrupt decrease of temperature (17 °C) or elevation of salinity (12 g per liter) was observed in the synbiotic treatment. Also, the total immunoglobulin and lysozyme activity level of skin mucus was significantly elevated in fish fed Artemia enriched with synbiotic (P < 0.05). These results revealed that feeding angelfish with synbiotic

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

    PubMed

    Durisko, Zachary; Dukas, Reuven

    2013-09-22

    We examined the use of social information in fruitfly larvae, which represent an ideal model system owing to their robust learning abilities, small number of neurons and well-studied neurogenetics. Focal larvae showed attraction to the distinct odour emanating from food occupied by other larvae. In controlled learning experiments, focal larvae preferred novel odours previously paired with food occupied by other larvae over novel odours previously paired with unoccupied food. When we gave groups of larvae a choice between food patches differing in quality, more larvae aggregated on the higher-quality food, suggesting that attraction to and learning about cues associated with other larvae can be beneficial. Furthermore, larvae were more likely to find the best available food patch in trials when that food patch was occupied by other larvae than in trials when that food patch was unoccupied. Our data suggest, however, that the benefits from joining others may be at least partially offset by the fitness costs of increased competition, because larvae reared in isolation did as well as or better than larvae reared in groups on three key fitness parameters: developmental rate, survival rate and adult dry body mass. Our work establishes fruitfly larvae as a highly tractable model species for further research on the mechanisms that modulate behaviour and learning in a social context.

  9. beta-Hydroxybutyrate in developing nauplii of brine shrimp (Artemia franciscana K.) under feeding and non-feeding conditions.

    PubMed

    Weltzien, F A; Hemre, G I; Evjemo, J O; Olsen, Y; Fyhn, H J

    2000-01-01

    Body content of beta-hydroxybutyrate, and individual dry mass, carbon content, and survival rate, were studied in developing nauplii of the brine shrimp Artemia franciscana K. from hatching to 96-97 h post hatching at 27 +/- 1 degrees C. The effect of two diets was studied in the experiment: Super Selco (SS) with a high lipid content; and Protein Selco (PS) with a high protein content. A starving group (S) was used as reference. The level of beta-hydroxybutyrate at hatching was 0.6 nmol.ind-1; it increased to 1.0-1.5 nmol.ind-1 in the SS- and S-groups, while in the PS-group it remained stable between 0.6-0.8 nmol.ind-1. At 60-80 h post hatch in the SS- and S-groups, the levels of beta-hydroxybutyrate were similar to the initial levels. The survival rate remained higher than 95% until 24 h post hatching in all groups. At the end of the experiment, the survival rate was 63% in the PS-group, 13% in the S-group and 3% in the SS-group. The Artemia nauplii individual dry mass and carbon content remained relatively stable in the SS-group; both parameters showed a significant increase in the PS-group and a significant decrease in the S-group. The results suggest that Artemia nauplii utilise ketone bodies as a fuel during development and growth, but that ketone catabolism may be overloaded by excessive lipid feeding resulting in increased mortality and possibly a ketotic acidosis.

  10. Effects of salinity on growth and survival in five Artemia franciscana (Anostraca: Artemiidae) populations from Mexico Pacific Coast.

    PubMed

    Castro-Mejía, Jorge; Castro-Barrera, Talía; Hernández-Hernández, Luis Héctor; Arredondo-Figueroa, José Luis; Castro-Mejía, Germán; de Lara-Andrade, Ramón

    2011-03-01

    Salinity is an important factor influencing growth and survival of aquatic organisms such as Artemia, a valuable aquaculture species. This study evaluated the effects of salinity on A. franciscana populations from different water bodies in Mexico's Pacific Coast. With this purpose, five autochthonous bisexual Artemia populations were tested to assess their survival and growth values against salinities of 40, 60, 80, 100 and 120 g/l, under laboratory conditions (25 +/- 2 degrees C; pH 8-10; constant light and aeration). The organisms were fed with 100 mL of rice bran and 2L of Tetraselmis suecica (500 000 cel/ml). The culture experiments were made in 200L plastic tanks, and survival and growth final values were obtained after 21 culture days. Survival and growth curves were determined by a regression analysis (R2). The significant differences between salinities were determined by ANOVA test (p < 0.05). The best survival and growth rates were found at salinities of 100-120 g/l. When the Mexican Artemia populations were cultivated at 40 g/l of salinity, 100% mortality was observed in the juvenile stage. This study determined that survival and growth values of A. franciscana populations increased with salinity. The five A. franciscana populations presented significant differences in their survival rate under various salinity regimes. The studied populations experienced high mortality at salinities under 60 g/l and over 200 g/l, and especially during the metanauplius stage. The present study confirms that growth rates in Mexican A. franciscana populations from Pacific Coast habitats are not inversely proportional to salinity. These A. franciscana populations should be cultured at 100-120 g/l of salinity to obtain better survival and growth rates. This data is useful to improve culture systems in aquaculture biomass production systems.

  11. Identification of the glycerol kinase gene and its role in diapause embryo restart and early embryo development of Artemia sinica.

    PubMed

    Cheng, Cheng; Yao, Feng; Chu, Bing; Li, Xuejie; Liu, Yan; Wu, Yang; Mei, Yanli; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

    2014-03-01

    Glycerol kinase (GK) catalyzes the rate-limiting step in glycerol utilization by transferring a phosphate from ATP to glycerol, yielding glycerol 3-phosphate, which is an important intermediate for both energy metabolism and glycerolipid production. Artemia sinica has an unusual diapause process under stress conditions of high salinity, low temperature and lack of food. In the process, diapause embryos of A. sinica (brine shrimp) accumulate high concentrations of glycerol as a cryoprotectant to prevent low temperature damage to embryos. Upon embryo restart, glycerol is converted into glucose and other carbohydrates. Therefore, GK plays an important role in the diapause embryo restart process. However, the role of GK in diapause termination of embryo development in A. sinica remains unknown. In the present study, a 2096 bp full-length cDNA of gk from A. sinica (As-gk) was obtained, encoding putative 551 amino acids, 60.6 kDa protein. As a crucial enzyme in glycerol uptake and metabolism, GK has been conserved structurally and functionally during evolution. The expression pattern of As-gk was investigated by quantitative real-time PCR and Western blotting. Expression locations of As-gk were analyzed using in situ hybridization. As-gk was widely distributed in the early embryo and several main parts of Artemia after differentiation. The expression of As-GK was also induced by stresses such as cold exposure and high salinity. This initial research into the expression pattern and stress response of GK in Artemia provides a sound basis for further understanding of the function and regulation of genes in early embryonic development in A. sinica and the stress response.

  12. Chitin-binding proteins of Artemia diapause cysts participate in formation of the embryonic cuticle layer of cyst shells.

    PubMed

    Ma, Wen-Ming; Li, Hua-Wei; Dai, Zhong-Min; Yang, Jin-Shu; Yang, Fan; Yang, Wei-Jun

    2013-01-01

    The brine shrimp Artemia reproduces either ovoviviparously, producing free-swimming nauplii, or oviparously, producing encysted embryos (diapause cysts) able to cope with harsh and complex habitats. When the cysts enter diapause they are encased in a complex external shell that protects them from certain extreme environments. The genomic comparison of oviparous and ovoviviparous ovisacs has been described previously. We isolated three significantly up-regulated genes in oviparous oocytes and identified them as Arp-CBP (Artemia parthenogenetica chitin-binding protein) genes. Quantitative real-time PCR indicated that the expression of Arp-CBP genes gradually increases during diapause cyst formation and significant mRNA accumulation occurs during the ovisac stage of oviparous development. Moreover, in situ hybridization results demonstrated that Arp-CBP mRNAs are expressed in the embryo. Interestingly, the results of immune electron microscopy showed that all three Arp-CBPs are distributed throughout the cellular ECL (embryonic cuticle layer) of the cyst shell. Furthermore, knockdown of Arp-CBP by RNA interference resulted in marked changes in the composition of the embryonic cuticular layer. The fibrous layer of the cyst shell adopted a loose conformation and the inner and outer cuticular membranes exhibited marked irregularities when Arp-CBP expression was suppressed. Finally, an in vitro recombinant protein-binding assay showed that all three Arp-CBPs have carbohydrate-binding activities. These findings provide significant insight into the mechanisms by which the ECL of Artemia cyst shell is formed, and demonstrate that Arp-CBPs are involved in construction of the fibrous lattice and are required for formation of the ECL of the cyst shell.

  13. Changes in developmental capacity of artemia cyst and chromosomal aberrations in lettuce seeds flown aboard Salyut-7 (Biobloc III experiment)

    NASA Astrophysics Data System (ADS)

    Nevzgodina, V.; Kovalev, E. E.; Maximova, E. N.; Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.; Clegg, J.

    This paper gives the results of investigations performed on the first container (A) of the Biobloc III experiment, flown aboard the orbital station Salyut 7 for 40 days. The space flight resulted in a decreased developmental capacity of Artemia cysts, hit or not hit by the HZE particles. No effect was observed in cysts in bulk. A synergetic effect of microgravity and gamma pre irradiation is described. The germination of in-flight lettuce seeds was decreased. The space flight resulted also in a higher percentage of cells with chromosomal aberrations. Relations between biological response, TEL and location of HZE particles are discussed.

  14. SEM study of diversity in the cyst surface topography of nine parthenogenetic Artemia (Crustacea: Anostraca) populations from China.

    PubMed

    Asem, Alireza; Sun, Shi-Chun

    2014-12-01

    The cysts of nine Chinese populations of parthenogenetic Artemia were studied by scanning electron microscope. In the 270 cysts examined, 15 different morphological patterns were recognized with most of them not recorded in previous studies and the "tubercled shell surface" being the most common pattern. Results also displayed high intrapopulation variability, with the maximum of 11 patterns (in 30 cysts) recorded from the Barkol population. No positive correlation between the diversity of cyst shell patterns and ploidy compositions was found. Principal components analysis suggests higher similarity among coastal populations than among inland populations, which may be attributed to the identity of physicochemical conditions among coastal salterns and dissimilarity among inland saline lakes.

  15. Naked eye instant reversible sensing of Cu(2+) and its in situ imaging in live brine shrimp Artemia.

    PubMed

    Nair, Ratish R; Raju, M; Patel, Neha P; Raval, Ishan H; Suresh, E; Haldar, Soumya; Chatterjee, Pabitra B

    2015-08-21

    A Cu(2+)-specific colorimetric reversible fluorescent receptor was designed and synthesized which showed a naked eye observable colour change from colourless to pink on addition of an aqueous buffer (pH 7.4) solution of 30 ppb Cu(2+). Short response time (≤5 s) and low detection limit (nearly 3 ppb) make suitable as a reliable "dip-in" open eye sensor for Cu(2+). Bio-imaging application in live brine shrimp Artemia enabled to detect Cu(2+) at as low as 10 ppb exposure.

  16. Map showing relative ease of excavation in the Salina quadrangle, Utah

    USGS Publications Warehouse

    Williams, Paul L.

    1972-01-01

    This map shows the relative ease (or difficulty) with which rocks and surficial deposits can be excavated. Because of rapidly changing technology of excavation and considerable local variability of many rock units, it is not practical to specifically categorize rock units according to type of equipment needed for their excavations. However, it may be stated in general that rock units classed as very easy and easy can in most places be excavated by hand tools and by light machinery such as backhoes and small bulldozers; units included in easy to difficult require blasting and (or) heavy machinery such as rippers and large bulldozers for resistant rocks, and hand tools or light power equipment for soft rocks; and units classes as difficult and very difficult probably require blasting and heavy machinery.The excavation units shown here are based on map units of the geologic map of the Salina quadrangle. Where bedrock is mantled with thin unmapped surficial deposits, ease of excavation shown is that of the bedrock, not that of the thin surficial mantle; where surficial deposits are mapped, ease of excavation shown is that of surficial deposits.

  17. Map showing length of freeze-free season in the Salina quadrangle, Utah

    USGS Publications Warehouse

    Covington, Harry R.

    1972-01-01

    In general, long freeze-free periods occur at low elevations, and short freeze-free periods occur at high elevations. But some valley floors have shorter freeze-free seasons than the glancing foothills because air cooled at high elevations flows downward and is trapped in the valleys. This temperature pattern occurs in the western part of the quadrangle in Rabbit Valley, Grass Valley, and the Sevier River Valley near Salina.Because year-round weather stations are sparse in Utah, a special technique for estimating length of freeze-free season was developed by Dr. Gaylen L. Ashcroft, Assistant Professor of Climatology, Utah State University, and E. Arlo Richardson, State Climatologist, U.S. Weather Bureau, based on average annual temperature, average annual temperature range, average daily temperature range, and average july maximum temperature. This technique was used in preparation of the map showing “Length of 32°F freeze-free season for Utah,” figure 23 in Hydrologic Atlas of Utah (Utah State University and Utah Division of Water Resources, 1968), from which the data for this map were taken.

  18. Concurrent changes in Dunaliella salina ultrastructure and membrane phospholipid metabolism after hyperosmotic shock

    PubMed Central

    1988-01-01

    Hyperosmotic shock, induced by raising the NaCl concentration of Dunaliella salina medium from 1.71 to 3.42 M, elicited a rapid decrease of nearly one-third in whole cell volume and in the volume of intracellular organelles. The decrease in cell volume was accompanied by plasmalemma infolding without overall loss of surface area. This contrasts with the dramatic increase in plasmalemma surface area after hypoosmotic shock (Maeda, M., and G. A. Thompson. 1986. J. Cell Biol. 102:289-297). Although plasmalemma surface area remained constant after hyperosmotic shock, the nucleus, chloroplast, and mitochondria lost membrane surface area, apparently through membrane fusion with the endoplasmic reticulum. Thus the endoplasmic reticulum serves as a reservoir for excess membrane during hyperosmotic stress, reversing its role as membrane donor to the same organelles during hypoosmotically induced cell expansion. Hyperosmotic shock also induced rapid changes in phospholipid metabolism. The mass of phosphatidic acid dropped to 56% of control and that of phosphatidylinositol 4,5-bisphosphate rose to 130% of control within 4 min. Further analysis demonstrated that within 10 min after hyperosmotic shock, there was 2.5-fold increase in phosphatidylcholine turnover, a twofold increase in lysophosphatidylcholine mass, a four-fold increase in lysophosphatidate mass, and an elevation in free fatty acids to 124% of control, all observations suggesting activation of phospholipase A. The observed biophysical and biochemical phenomena are likely to be causally interrelated in providing mechanisms for successful accommodation to such severe osmotic extremes. PMID:3417760

  19. Effects of Light and Temperature on Fatty Acid Production in Nannochloropsis Salina

    SciTech Connect

    Van Wagenen, Jonathan M.; Miller, Tyler W.; Hobbs, Samuel J.; Hook, Paul W.; Crowe, Braden J.; Huesemann, Michael H.

    2012-03-12

    Accurate prediction of algal biofuel yield will require empirical determination of physiological responses to the climate, particularly light and temperature. One strain of interest, Nannochloropsis salina, was subjected to ranges of light intensity (5-850 {mu}mol m{sup -2} s{sup -1}) and temperature (13-40 C); exponential growth rate, total fatty acids (TFA) and fatty acid composition were measured. The maximum acclimated growth rate was 1.3 day{sup -1} at 23 C and 250 {mu}mol m{sup -2} s{sup -1}. Fatty acids were detected by gas chromatography with flame ionization detection (GC-FID) after transesterification to corresponding fatty acid methyl esters (FAME). A sharp increase in TFA containing elevated palmitic acid (C16:0) and palmitoleic acid (C16:1) during exponential growth at high light was observed, indicating likely triacylglycerol accumulation due to photo-oxidative stress. Lower light resulted in increases in the relative abundance of unsaturated fatty acids; in thin cultures, increases were observed in palmitoleic and eicosapentaenoeic acids (C20:5{omega}3). As cultures aged and the effective light intensity per cell converged to very low levels, fatty acid profiles became more similar and there was a notable increase of oleic acid (C18:1{omega}9). The amount of unsaturated fatty acids was inversely proportional to temperature, demonstrating physiological adaptations to increase membrane fluidity. This data will improve prediction of fatty acid characteristics and yields relevant to biofuel production.

  20. A complex family of class-II restriction endonucleases, DsaI-VI, in Dactylococcopsis salina.

    PubMed

    Laue, F; Evans, L R; Jarsch, M; Brown, N L; Kessler, C

    1991-01-02

    A series of class-II restriction endonucleases (ENases) was discovered in the halophilic, phototrophic, gas-vacuolated cyanobacterium Dactylococcopsis salina sp. nov. The six novel enzymes are characterized by the following recognition sequences and cut positions: 5'-C decreases CRYGG-3' (DsaI); 5'-GG decreases CC-3' (DsaII); 5'-R decreases GATCY-3' (DsaIII); 5'-G decreases GWCC-3' (DsaIV); 5'-decreases CCNGG-3' (DsaV); and 5'-GTMKAC-3' (DsaVI), where W = A or T, M = A or C, K = G or T, and N = A, G, C or T. In addition, traces of further possible activity were detected. DsaI has a novel sequence specificity and DsaV is an isoschizomer of ScrFI, but with a novel cut specificity. A purification procedure was established to separate all six ENases, resulting in their isolation free of contaminating nuclease activities. DsaI cleavage is influenced by N6-methyladenine residues [derived from the Escherichia coli-encoded DNA methyltransferase (MTase) M.Eco damI] within the overlapping sequence, 5'-CCRYMGGATC-3'; DsaV hydrolysis is inhibited by a C-5-methylcytosine residue in its recognition sequence (5'-CMCNGG-3'), generated in some DsaV sites by the E. coli-encoded MTase, M.Eco dcmI.

  1. Studies on the biochemistry and physiology of inositol phospholipids in Dunaliella salina

    SciTech Connect

    Einspahr, K.J.

    1988-01-01

    In the unicellular alga, Dunaliella salina, phosphatidylinositol, phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol 4,5-bisphosphate (PIP{sub 2}) comprise 14.8, 1.2, and 0.3 mol %, respectively, of cellular phospholipids. In isolated plasma membrane fractions, PIP and PIP{sub 2} are highly concentrated, together comprising 9.5 mol % of plasmalemma phospholipids. The metabolism of these inositol phospholipids and phosphatidic acid (PA) is very rapid under normal growth conditions, as illustrated by the fact that within 5 minutes after introduction of {sup 32}P{sub i} into the growth medium over 75% of lipid-bound label was found in these quantitatively minor phospholipids. Within 2 minutes after a sudden hypoosmotic shock, the levels of PIP{sub 2} and PIP dropped to 65 and 79%, respectively, of controls. Within the same time frame PA rose to 141% of control values. These data suggest that a rapid breakdown of the polyphosphoinositides may mediate the profound morphological and physiological changes which allow this organism to survive drastic hypoosmotic stress.

  2. PCR-identification of Dunaliella salina (Volvocales, Chlorophyta) and its growth characteristics.

    PubMed

    Raja, Rathinam; Hema Iswarya, Shanmugam; Balasubramanyam, Dakshanamoorthy; Rengasamy, Ramasamy

    2007-01-01

    The saline pond microalga, Dunaliella salina (Dunal) Teod. maintained in De Walne's (basal) medium under laboratory conditions was confirmed by amplifying the chromosomal DNA of the microalga by PCR with specific primers MA1 and MA2. Seaweed extracts obtained from Sargassum wightii and Ulva lactuca were amended separately at 1.0%, 1.5%, 2.0% and 2.5% levels to the basal medium in order to assess their potential on the growth and concentration of pigments, viz. Chl a, Chl b and beta-carotene of the alga. beta-Carotene was isolated and visible absorption spectrum was taken at 443 and 475 nm confirmed the presence of 9-cis-beta-carotene and all-trans-beta-carotene isomers. Maximum yield, highest division rate (mu) and highest pigment concentrations were observed in the cells grown in 1.5% S. wightii and 2.0% U. lactuca amended medium and these cells were subjected to DAPI staining. The results of epifluorescence microscopy and image analysis revealed a significant enhancement of the cell and nuclear area of the microalgae.

  3. Optimization of the extraction of antioxidants from Dunaliella salina microalga by pressurized liquids.

    PubMed

    Herrero, Miguel; Jaime, Laura; Martín-Alvarez, Pedro J; Cifuentes, Alejandro; Ibáñez, Elena

    2006-07-26

    In this work, extraction of antioxidant compounds from Dunaliella salina microalga is optimized by combining pressurized liquid extraction (PLE) and experimental design (three-level factorial design) with three different solvents (hexane, ethanol, and water). Two main factors were considered, the extraction temperature (40, 100, and 160 degrees C) and the extraction time (5, 17.5, and 30 min). As response variables, the extraction yield (percent dry weight/initial weight) and the antioxidant activity of the extracts (determined using the TEAC method) were used. The parameters of the model were estimated by multiple linear regression. Results showed that the extraction temperature was the factor having the strongest influence (positive) on the two response variables. The best yields were obtained with ethanol at the higher extraction temperature and time tested. Besides, although hexane extracts provided the best antioxidant activity, ethanol extracts were also very active. The chemical characterization of ethanol extracts was carried out using HPLC-DAD, and attempts have been made to correlate their chemical composition with the antioxidant activity measured. Results pointed out that the extracts contained, besides all-trans-beta-carotene and isomers, several different minor carotenoids that seemed to make a contribution to the antioxidant activity of the extracts.

  4. Death of a carbonate basin: The Niagara-Salina transition in the Michigan basin

    SciTech Connect

    Leibold, A.W.; Howell, P.D. )

    1991-03-01

    The A-O Carbonate in the Michigan basin comprises a sequence of laminated calcite/anhydrite layers intercalated with bedded halite at the transition between normal marine Niagaran carbonates and lower Salina Group evaporites. The carbonate/anhydrite interbeds represent freshing events during initial evaporative concentration of the Michigan basin. Recent drilling in the Michigan basin delineates two distinct regions of A-O Carbonate development: a 5 to 10 m thick sequence of six 'laminites' found throughout most of the western and northern basin and a 10 to 25 m thick sequence in the southeastern basin containing both thicker 'laminates' and thicker salt interbeds. Additionally, potash deposits of the overlying A-1 evaporite unit are restricted to the northern and western basin regions. The distribution of evaporite facies in these two regions is adequately explained by a source of basin recharge in the southeast-perhaps the 'Clinton Inlet' of earlier workers. This situation suggest either that: (1) the source of basin recharge is alternately supplying preconcentrated brine and more normal marine water, or (2) that the basin received at least two distinct sources of water during A-O deposition.

  5. Determination of Ion Content and Ion Fluxes in the Halotolerant Alga Dunaliella salina

    PubMed Central

    Pick, Uri; Karni, Leah; Avron, Mordhay

    1986-01-01

    A method to determine intracellular cation contents in Dunaliella by separation on cation-exchange minicolumns is described. The separation efficiency of cells from extracellular cations is over 99.9%; the procedure causes no apparent perturbation to the cells and can be applied to measure both fluxes and internal content of any desired cation. Using this technique it is demonstrated that the intracellular averaged Na+, K+, and Ca2+ concentrations in Dunaliella salina cultured at 1 to 4 molar NaCl, 5 millimolar K+, and 0.3 millimolar Ca2+ are 20 to 100 millimolar, 150 to 250 millimolar, and 1 to 3 millimolar, respectively. The intracellular K+ concentration is maintained constant over a wide range of media K+ concentrations (0.5-10 millimolar), leading to a ratio of K+ in the cells to K+ in the medium of 10 to 1,000. Severe limitation of external K+, induces loss of K+ and increase in Na+ inside the cells. The results suggest that Dunaliella cells possess efficient mechanisms to eliminate Na+ and accumulate K+ and that intracellular Na+ and K+ concentrations are carefully regulated. The contribution of the intracellular Na+ and K+ salts to the total osmotic pressure of cells grown at 1 to 4 molar NaCl, is 5 to 20%. PMID:16664814

  6. Suppressing bullfrog larvae with carbon dioxide

    USGS Publications Warehouse

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  7. Evolution of foraging behavior in Drosophilid larvae

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  8. Appetitive associative olfactory learning in Drosophila larvae.

    PubMed

    Apostolopoulou, Anthi A; Widmann, Annekathrin; Rohwedder, Astrid; Pfitzenmaier, Johanna E; Thum, Andreas S

    2013-02-18

    In the following we describe the methodological details of appetitive associative olfactory learning in Drosophila larvae. The setup, in combination with genetic interference, provides a handle to analyze the neuronal and molecular fundamentals of specifically associative learning in a simple larval brain. Organisms can use past experience to adjust present behavior. Such acquisition of behavioral potential can be defined as learning, and the physical bases of these potentials as memory traces. Neuroscientists try to understand how these processes are organized in terms of molecular and neuronal changes in the brain by using a variety of methods in model organisms ranging from insects to vertebrates. For such endeavors it is helpful to use model systems that are simple and experimentally accessible. The Drosophila larva has turned out to satisfy these demands based on the availability of robust behavioral assays, the existence of a variety of transgenic techniques and the elementary organization of the nervous system comprising only about 10,000 neurons (albeit with some concessions: cognitive limitations, few behavioral options, and richness of experience questionable). Drosophila larvae can form associations between odors and appetitive gustatory reinforcement like sugar. In a standard assay, established in the lab of B. Gerber, animals receive a two-odor reciprocal training: A first group of larvae is exposed to an odor A together with a gustatory reinforcer (sugar reward) and is subsequently exposed to an odor B without reinforcement. Meanwhile a second group of larvae receives reciprocal training while experiencing odor A without reinforcement and subsequently being exposed to odor B with reinforcement (sugar reward). In the following both groups are tested for their preference between the two odors. Relatively higher preferences for the rewarded odor reflect associative learning--presented as a performance index (PI). The conclusion regarding the associative

  9. Caspase activity during cell stasis: avoidance of apoptosis in an invertebrate extremophile, Artemia franciscana.

    PubMed

    Menze, Michael A; Hand, Steven C

    2007-05-01

    Evaluation of apoptotic processes downstream of the mitochondrion reveals caspase-9- and low levels of caspase-3-like activities in partly purified extracts of Artemia franciscana embryos. However, in contrast to experiments with extracts of human hepatoma cells, cytochrome c fails to activate caspase-3 or -9 in extracts from A. franciscana. Furthermore, caspase-9 activity is sensitive to exogenous calcium. The addition of 5 mM calcium leads to a 4.86 +/- 0.19 fold (SD) (n = 3) increase in activity, which is fully prevented with 150 mM KCl. As with mammalian systems, high ATP (>1.25 mM) suppresses caspase activity in A. franciscana extracts. A strong inhibition of caspase-9 activity was also found by GTP. Comparison of GTP-induced inhibition of caspase-9 at 0 and 2.5 mM MgCl(2) indicates that free (nonchelated) GTP is likely to be the inhibitory form. The strongest inhibition among all nucleotides tested was with ADP. Inhibition by ADP in the presence of Mg(2+) is 60-fold greater in diapause embryos than in postdiapause embryos. Because ADP does not change appreciably in concentration between the two physiological states, it is likely that this differential sensitivity to Mg(2+)-ADP is important in avoiding caspase activation during diapause. Finally, mixtures of nucleotides that mimic physiological concentrations in postdiapause and diapause states underscore the depressive action of these regulators on caspase-9 during diapause. Our biochemical characterization of caspase-like activity in A. franciscana extracts reveals that multiple mechanisms are in place to reduce the probability of apoptosis under conditions of energy limitation in this embryo.

  10. A novel 49-kilodalton protein from Artemia cross-links microtubules in vitro.

    PubMed

    Zhang, J; MacRae, T H

    1992-01-01

    A 49 kilodalton (kDa) protein, previously proposed to cross-link microtubules, was purified to apparent homogeneity from cell-free extracts of the brine shrimp Artemia. When incubated with tubulin under assembly conditions, the purified 49-kDa protein cross-linked the resulting microtubules. Preformed microtubules were also cross-linked when incubated with the 49-kDa protein. Upon centrifugation through sucrose cushions the 49-kDa protein cosedimented with microtubules, suggesting a stable association between the cross-linking protein and tubulin. Such microtubules were interconnected by particles which were circular, bilobed, or elongated in shape. Disruption of microtubule cross-linking and dissociation of the 49-kDa protein from microtubules occurred in the presence of ATP and 5'-adenylyl-imidodiphosphate (AMP-PNP), a nonhydrolyzable analogue of ATP. The 49-kDa protein was moderately resistant to heat, it did not stimulate tubulin assembly, and it did not react with antibodies to neural microtubule-associated proteins (MAPs) and kinesin. These observations indicate that the 49-kDa protein is different from many known MAPs, a conclusion strengthened by the inability of antibodies raised to the 49-kDa protein to recognize these proteins. The amino terminal 15 amino acid residues of the 49-kDa protein were determined by Edman digestion and an antibody raised to this peptide reacted with the 49-kDa protein on Western blots. Microtubule cross-linking was unaffected by the synthetic amino-terminal peptide, even when it was present at a fivefold molar excess over the 49-kDa protein. A search of three protein databanks revealed that the amino terminus of the 49-kDa protein is unique among published sequences.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Liposomes with diverse compositions are protected during desiccation by LEA proteins from Artemia franciscana and trehalose.

    PubMed

    Moore, Daniel S; Hansen, Richard; Hand, Steven C

    2016-01-01

    Intracellular accumulation of Late Embryogenesis Abundant (LEA) proteins and the disaccharide trehalose is associated with cellular desiccation tolerance in a number of animal species. Two LEA proteins from anhydrobiotic embryos of the brine shrimp Artemia franciscana were tested for the ability to protect liposomes of various compositions against desiccation-induced damage in the presence and absence of trehalose. Damage was assessed by carboxyfluorescein leakage after drying and rehydration. Further, using a cytoplasmic-localized (AfrLEA2) and a mitochondrial-targeted (AfrLEA3m) LEA protein allowed us to evaluate whether each may preferentially stabilize membranes of a particular lipid composition based on the protein's subcellular location. Both LEA proteins were able to offset damage during drying of liposomes that mimicked the lipid compositions of the inner mitochondrial membrane (with cardiolipin), outer mitochondrial membrane, and the inner leaflet of the plasma membrane. Thus liposome stabilization by AfrLEA3m or AfrLEA2 was not dependent on lipid composition, provided physiological amounts of bilayer and non-bilayer-forming lipids were present (liposomes with a non-biological composition of 100% phosphatidylcholine were not protected by either protein). Additive protection by LEA proteins plus trehalose was dependent on the lipid composition of the target membrane. Minimal additional damage occurred to liposomes stored at room temperature in the dried state for one week compared to liposomes rehydrated after 24h. Consistent with the ability to stabilize lipid bilayers, molecular modeling of the secondary structures for AfrLEA2 and AfrLEA3m revealed bands of charged amino acids similar to other amphipathic proteins that interact directly with membranes.

  12. Identification, expression pattern, cellular location and potential role of the caveolin-1 gene from Artemia sinica.

    PubMed

    Li, Xuejie; Yao, Feng; Zhang, Wei; Cheng, Cheng; Chu, Bing; Liu, Yan; Mei, Yanli; Wu, Yang; Zou, Xiangyang; Hou, Lin

    2014-05-01

    Caveolins are integral membrane proteins that serve as scaffolds to recruit numerous signaling molecules. Caveolins play an important role in membrane trafficking, signal transduction, substrate transport and endocytosis in differentiated cells. In this study, a caveolin-1 gene from Artemia sinica (As-cav-1) was successfully cloned for the first time. The full-length cDNA of As-cav-1 comprises 974 bp, with a 675 bp open reading frame (ORF) that encodes a polypeptide of 224 amino acids with a caveolin scaffolding domain (CSD) and two transmembrane domains. Multiple sequence alignment revealed that the putative As-CAV-1 protein sequence was relatively conserved across species, especially in the CSD domain. Real-time PCR revealed high levels of the As-cav-1 transcript at 0h of embryo development. Furthermore, As-cav-1 transcripts were highly upregulated under high salinity (200‰) and low temperature stresses (15°C). To further characterize As-cav-1, recombinant pET30a-cav-1 protein was expressed using a prokaryotic expression system. The recombinant protein comprised 290 amino acids with a theoretical molecular weight of 32kDa, and a predicted isoelectric point of 5.6. Western blotting of the expression levels of As-CAV-1 during different embryo development stages revealed that As-CAV-1 levels decreased gradually during development stages from 0 h to 40 h, and increased at 3d. Furthermore, western blotting showed that As-CAV-1 was upregulated to its highest expression level by low temperature stress (15°C) and high salinity. Confocal laser microscopy analysis, using antibodies generated against the recombinant As-CAV-1 protein, showed that As-CAV-1 was mostly located in the cell membrane. Our results suggested that As-cav-1 plays a vital role in protecting embryos from high salt damage and low temperature stress, especially during post-diapause embryonic development.

  13. Artemia franciscana as a vector for infectious myonecrosis virus (IMNV) to Litopenaeus vannamei juvenile.

    PubMed

    da Silva, Suzianny Maria Bezerra Cabral; Lavander, Henrique David; de Santana Luna, Manuella Maria; de Melo Eloi da Silva, Ana Odete; Gálvez, Alfredo Olivera; Coimbra, Maria Raquel Moura

    2015-03-01

    In 2004, the infectious myonecrosis virus (IMNV) was recognized as the main cause of Litopenaeusvannamei shrimp culture's drop in Brazil. In health animal control programs, in order to reduce virus prevalence in production units it is necessary to screen live feed used. Among live diets used in aquaculture, the brine shrimp Artemia sp. is essential in crustacean larviculture and maturation. The aim of the present study was to investigate the susceptibility of Artemiafranciscana to IMNV through an immersion challenge and virus-phytoplankton adhesion route and to elucidate its role as a vector for IMNV transmission to L.vannamei. A. franciscana adults were infected with IMNV through both routes, as demonstrated by PCR-positive reactions. However, infected A. franciscana showed no signs of infection. More than 40% of L. vannamei juveniles fed with IMNV-infected A. franciscana by virus-phytoplankton adhesion route were positive by real-time PCR, whereas only a 10% infection rate was found among shrimp fed with IMNV-infected brine shrimp using the immersion challenge. Significant differences were found in mean viral load between immersion and virus-phytoplankton adhesion shrimp treatments (p ⩽ 0.05). Moreover, the mean viral loads were 1.34 × 10(2) and 1.48 × 10(4) copies/μg(-1) of total RNA for virus-phytoplankton adhesion and IMNV-infected tissue treatments, respectively, and the difference was not significant (p ⩾ 0.05). The results indicated that A. franciscana act as a vector for IMNV transmission under the experimental conditions examined. Although no mass mortalities were detected in L. vannamei fed with IMNV-infected brine shrimp, these infected shrimp should not be disregarded as a source of IMNV in grow-out units.

  14. Carabid larvae as predators of weed seeds: granivory in larvae of Amara eurynota (Coleoptera: Carabidae).

    PubMed

    Saska, Pavel

    2004-01-01

    Up to date we do not have much information about predation on seeds by larvae of ground beetles. One of the reasons why such knowledge is important is that granivorous larvae contribute to predation of weed seeds. In this study, the food requirements of larvae of autumn breeding carabid species Amara eurynota (Panzer) were investigated in the laboratory and a hypothesis, that they are granivorous was tested. Insect diet (Tenebrio molitor larvae), three seed diets (seeds of Artemisia vulgaris, Tripleurospermum inodorum or Urtica dioica or a mixed diet (T. molitor + A. uulgaris) were used as food. For larvae of A. eurynota, seeds are essential for successful completion of development, because all those fed pure insect diet died before pupation. However, differences in suitability were observed between pure seed diets. Larvae fed seeds of A. vulgaris had the lowest mortality and fastest development of the seed diets. Those fed seeds of T. inodorum had also low mortality, but the development was prolonged in the third instar. In contrast, development of larvae reared on seeds of U. dioica was slowest of the tested diets and could not be completed, as all individuals died before pupation. When insects were included to seed diet of A. vulgaris (mixed diet), the duration of development shortened, but mortality remained the same when compared to seed diet of A. vulgaris. According to the results it was concluded that larvae of A. eurynota are granivorous. A mixed diet and seed diets of A. uulgaris and T. inodorum were suitable and insect diet and seeds of U. dioica were unsuitable diets in this experiment.

  15. [Larvae of barnacles (Cirripedia: Thoracica) in the White sea plankton].

    PubMed

    Poltarukha, O P

    2003-01-01

    The barnacle fauna in the White Sea is briefly described. The morphology of barnacle larvae in this water body is comparatively analyzed. The characters important for the larvae identification are given particular attention. A classification key was developed for the nauplius and cyprid larvae of barnacles in the White Sea.

  16. Workbook on the Identification of Anopheles Larvae. Preliminary Issue.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; Stojanovich, Chester J.

    This self-instructional booklet is designed to enable malarial control workers to identify the larvae of "Anopheles" species that are important malaria vectors. The morphological features of the larvae are illustrated in a programed booklet, which also contains an illustrated taxonomic key to 25 species of anopheline larvae. A glossary and a short…

  17. An Introduction to the Identification of Chironomid Larvae.

    ERIC Educational Resources Information Center

    Mason, William T., Jr.

    This publication is an introductory guide to the identification of Chironomid (Midge) larvae. The larvae of these small flies are an important link in the food chain between algae and microinvertebrates. As a family, the larvae exhibit a wide range of tolerance to environmental factors such as amounts and types of pollutants. Much of this…

  18. Quantitative proteomic analysis of thylakoid from two microalgae (Haematococcus pluvialis and Dunaliella salina) reveals two different high light-responsive strategies.

    PubMed

    Gu, Wenhui; Li, Huan; Zhao, Peipei; Yu, Ruixue; Pan, Guanghua; Gao, Shan; Xie, Xiujun; Huang, Aiyou; He, Linwen; Wang, Guangce

    2014-10-22

    Under high light (HL) stress, astaxanthin-accumulating Haematococcus pluvialis and β-carotene-accumulating Dunaliella salina showed different responsive patterns. To elucidate cellular-regulating strategies photosynthetically and metabolically, thylakoid membrane proteins in H. pluvialis and D. salina were extracted and relatively quantified after 0 h, 24 h and 48 h of HL stress. Proteomic analysis showed that three subunits of the cytochrome b6/f complex were greatly reduced under HL stress in H. pluvialis, while they were increased in D. salina. Additionally, the major subunits of both photosystem (PS) II and PSI reaction center proteins were first reduced and subsequently recovered in H. pluvialis, while they were gradually reduced in D. salina. D. salina also showed a greater ability to function using the xanthophyll-cycle and the cyclic photosynthetic electron transfer pathway compared to H. pluvialis. We propose a reoriented and effective HL-responsive strategy in H. pluvialis, enabling it to acclimate under HL. The promising metabolic pathway described here contains a reorganized pentose phosphate pathway, Calvin cycle and glycolysis pathway participating in carbon sink formation under HL in H. pluvialis. Additionally, the efficient carbon reorientation strategy in H. pluvialis was verified by elevated extracellular carbon assimilation and rapid conversion into astaxanthin.

  19. Effects of surface-engineered nanoparticle-based dispersants for marine oil spills on the model organism Artemia franciscana.

    PubMed

    Rodd, April L; Creighton, Megan A; Vaslet, Charles A; Rangel-Mendez, J Rene; Hurt, Robert H; Kane, Agnes B

    2014-06-03

    Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50-1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25-50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25-75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms.

  20. Multi-response optimization of Artemia hatching process using split-split-plot design based response surface methodology.

    PubMed

    Arun, V V; Saharan, Neelam; Ramasubramanian, V; Babitha Rani, A M; Salin, K R; Sontakke, Ravindra; Haridas, Harsha; Pazhayamadom, Deepak George

    2017-01-16

    A novel method, BBD-SSPD is proposed by the combination of Box-Behnken Design (BBD) and Split-Split Plot Design (SSPD) which would ensure minimum number of experimental runs, leading to economical utilization in multi- factorial experiments. The brine shrimp Artemia was tested to study the combined effects of photoperiod, temperature and salinity, each with three levels, on the hatching percentage and hatching time of their cysts. The BBD was employed to select 13 treatment combinations out of the 27 possible combinations that were grouped in an SSPD arrangement. Multiple responses were optimized simultaneously using Derringer's desirability function. Photoperiod and temperature as well as temperature-salinity interaction were found to significantly affect the hatching percentage of Artemia, while the hatching time was significantly influenced by photoperiod and temperature, and their interaction. The optimum conditions were 23 h photoperiod, 29 °C temperature and 28 ppt salinity resulting in 96.8% hatching in 18.94 h. In order to verify the results obtained from BBD-SSPD experiment, the experiment was repeated preserving the same set up. Results of verification experiment were found to be similar to experiment originally conducted. It is expected that this method would be suitable to optimize the hatching process of animal eggs.

  1. Intestinal uptake of lipovitellin from brine shrimp (Artemia franciscana) by larval inland silversides (Menidia beryllina) and striped bass (Morone saxatilis).

    PubMed

    Kishida, M; Johanning, K M; Bengtson, D A; Specker, J L

    1998-01-01

    Intestinal uptake of lipovitellin (LV) from brine shrimp (Artemia franciscana) in larval inland silversides (Menidia beryllina) and striped bass (Morone saxatilis) was described using immunocytochemistry. Polyclonal antisera were raised against two subunits of LV (LV68 and LV190). When tested by immunocytochemistry, anti-LV68 showed cross-reactivity with some of the pancreatic cells especially in inland silversides. Therefore anti-LV190 was used to localize immunoreactive LV. Inland silversides at 14 days after hatching were fed Artemia nauplii and then sampled 4, 8, 12 hr after feeding. Similar experiments were carried out by using striped bass at 5 days and 15 days of age. They were sampled at 2, 4, 8, and 12 hr after feeding. Anterior enterocytes showed no evidence of uptake; however, the brush border of the cells of inland silversides reacted with the antiserum. Posterior enterocytes took up the LV and/or, possibly, their immunoreactive breakdown products. The pattern of uptake included accumulation in supranuclear vacuoles and digestion in supranuclear vacuoles, as suggested by the decay of the immunoreactivity over time. Thus, the posterior intestine of these larval fishes is the site of uptake and digestion of LV, an important nutritive component in the food of many larval fishes; this supports earlier findings using non-nutritive marker proteins.

  2. Multi-response optimization of Artemia hatching process using split-split-plot design based response surface methodology

    PubMed Central

    Arun, V. V.; Saharan, Neelam; Ramasubramanian, V.; Babitha Rani, A. M.; Salin, K. R.; Sontakke, Ravindra; Haridas, Harsha; Pazhayamadom, Deepak George

    2017-01-01

    A novel method, BBD-SSPD is proposed by the combination of Box-Behnken Design (BBD) and Split-Split Plot Design (SSPD) which would ensure minimum number of experimental runs, leading to economical utilization in multi- factorial experiments. The brine shrimp Artemia was tested to study the combined effects of photoperiod, temperature and salinity, each with three levels, on the hatching percentage and hatching time of their cysts. The BBD was employed to select 13 treatment combinations out of the 27 possible combinations that were grouped in an SSPD arrangement. Multiple responses were optimized simultaneously using Derringer’s desirability function. Photoperiod and temperature as well as temperature-salinity interaction were found to significantly affect the hatching percentage of Artemia, while the hatching time was significantly influenced by photoperiod and temperature, and their interaction. The optimum conditions were 23 h photoperiod, 29 °C temperature and 28 ppt salinity resulting in 96.8% hatching in 18.94 h. In order to verify the results obtained from BBD-SSPD experiment, the experiment was repeated preserving the same set up. Results of verification experiment were found to be similar to experiment originally conducted. It is expected that this method would be suitable to optimize the hatching process of animal eggs. PMID:28091611

  3. Multi-response optimization of Artemia hatching process using split-split-plot design based response surface methodology

    NASA Astrophysics Data System (ADS)

    Arun, V. V.; Saharan, Neelam; Ramasubramanian, V.; Babitha Rani, A. M.; Salin, K. R.; Sontakke, Ravindra; Haridas, Harsha; Pazhayamadom, Deepak George

    2017-01-01

    A novel method, BBD-SSPD is proposed by the combination of Box-Behnken Design (BBD) and Split-Split Plot Design (SSPD) which would ensure minimum number of experimental runs, leading to economical utilization in multi- factorial experiments. The brine shrimp Artemia was tested to study the combined effects of photoperiod, temperature and salinity, each with three levels, on the hatching percentage and hatching time of their cysts. The BBD was employed to select 13 treatment combinations out of the 27 possible combinations that were grouped in an SSPD arrangement. Multiple responses were optimized simultaneously using Derringer’s desirability function. Photoperiod and temperature as well as temperature-salinity interaction were found to significantly affect the hatching percentage of Artemia, while the hatching time was significantly influenced by photoperiod and temperature, and their interaction. The optimum conditions were 23 h photoperiod, 29 °C temperature and 28 ppt salinity resulting in 96.8% hatching in 18.94 h. In order to verify the results obtained from BBD-SSPD experiment, the experiment was repeated preserving the same set up. Results of verification experiment were found to be similar to experiment originally conducted. It is expected that this method would be suitable to optimize the hatching process of animal eggs.

  4. Effects of Surface-Engineered Nanoparticle-Based Dispersants for Marine Oil Spills on the Model Organism Artemia franciscana

    PubMed Central

    2015-01-01

    Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50–1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25–50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25–75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms. PMID:24823274

  5. Group 1 LEA proteins contribute to the desiccation and freeze tolerance of Artemia franciscana embryos during diapause.

    PubMed

    Toxopeus, Jantina; Warner, Alden H; MacRae, Thomas H

    2014-11-01

    Water loss either by desiccation or freezing causes multiple forms of cellular damage. The encysted embryos (cysts) of the crustacean Artemia franciscana have several molecular mechanisms to enable anhydrobiosis-life without water-during diapause. To better understand how cysts survive reduced hydration, group 1 late embryogenesis abundant (LEA) proteins, hydrophilic unstructured proteins that accumulate in the stress-tolerant cysts of A. franciscana, were knocked down using RNA interference (RNAi). Embryos lacking group 1 LEA proteins showed significantly lower survival than control embryos after desiccation and freezing, or freezing alone, demonstrating a role for group 1 LEA proteins in A. franciscana tolerance of low water conditions. In contrast, regardless of group 1 LEA protein presence, cysts responded similarly to hydrogen peroxide (H2O2) exposure, indicating little to no function for these proteins in diapause termination. This is the first in vivo study of group 1 LEA proteins in an animal and it contributes to the fundamental understanding of these proteins. Knowing how LEA proteins protect A. franciscana cysts from desiccation and freezing may have applied significance in aquaculture, where Artemia is an important feed source, and in the cryopreservation of cells for therapeutic applications.

  6. Probing the phenomenon of trained immunity in invertebrates during a transgenerational study, using brine shrimp Artemia as a model system.

    PubMed

    Norouzitallab, Parisa; Baruah, Kartik; Biswas, Priyanka; Vanrompay, Daisy; Bossier, Peter

    2016-02-15

    The invertebrate's innate immune system was reported to show some form of adaptive features, termed trained immunity. However, the memory characteristics of innate immune system and the mechanisms behind such phenomena remain unclear. Using the invertebrate model Artemia, we verified the possibility or impossibility of trained immunity, examining the presence or absence of enduring memory against homologous and heterologous antigens (Vibrio spp.) during a transgenerational study. We also determined the mechanisms behind such phenomenon. Our results showed the occurrence of memory and partial discrimination in Artemia's immune system, as manifested by increased resistance, for three successive generations, of the progenies of Vibrio-exposed ancestors towards a homologous bacterial strain, rather than to a heterologous strain. This increased resistance phenotype was associated with elevated levels of hsp70 and hmgb1 signaling molecules and alteration in the expression of key innate immunity-related genes. Our results also showed stochastic pattern in the acetylation and methylation levels of H4 and H3K4me3 histones, respectively, in the progenies whose ancestors were challenged. Overall results suggest that innate immune responses in invertebrates have the capacity to be trained, and epigenetic reprogramming of (selected) innate immune effectors is likely to have central place in the mechanisms leading to trained immunity.

  7. Identification, expression pattern and functional characterization of As-kip2 in diapause embryo restarting process of Artemia sinica.

    PubMed

    Zhang, Mengchen; Yao, Feng; Qin, Tong; Hou, Lin; Zou, Xiangyang

    2017-04-15

    Proper control of the cellular processes requires a variety of regulatory proteins that are involved in the cell cycle, proliferation and apoptosis. Cyclin-dependent kinase inhibitor (CKI) negatively regulates transcription and arrests the cell cycle in G1 phase. KIP2 is a member of CKI family, which could inhibit proliferation by tight-binding with several cyclin-CDK complexes. During the embryonic development of the brine shrimp, Artemia sinica, KIP2 plays a key role in the cell cycle regulation, but the specific mechanisms remain unknown. Herein, the 1023bp full-length cDNA of kip2 from A. sinica was cloned. The mRNA expression patterns of As-kip2, As-carp-1 in different development stages and pattern of As-kip2 under environmental stresses were investigated. In situ hybridization of As-kip2 mRNA and immunofluorescence of As-CARP-1 protein showed no tissue or organ specificity. Furthermore, western blotting showed the expressions levels of As-KIP2, As-E2F1, As-p53, As-cyclin E, As-SODD protein, and pattern of As-KIP2 under environmental stresses. Our research revealed that As-KIP2 plays crucial role in the restarting process of diapause embryo in Artemia sinica.

  8. A note on the biogeographical origin of the brine shrimp Artemia urmiana Günther, 1899 from Urmia Lake, Iran.

    PubMed

    Eimanifar, Amin; Asem, Alireza; Djamali, Morteza; Wink, Michael

    2016-03-30

    The brine shrimp Artemia urmiana, an abundant inhabitant of the hypersaline Urmia Lake in northwestern Iran, has recently been described from Lake Koyashskoe, also a shallow hypersaline lake that is located on the Black Sea coast of the Crimean Peninsula (Ukraine). This discovery has questioned the endemicity of A. urmiana in Urmia Lake and has also brought into question the biogeographical origin of this species. In the present study, we combined recent genetic divergence data (mtDNA-COI) with palaeoecological evidence to address the biogeographical origin of A. urmiana. Calibration of the molecular clock of the COI region was set by assigning the age of the micro-crustacean Daphnia pulex minimally at 145 Mya. The divergence age of A. urmiana in Urmia Lake dates back to 383,000 years, whereas Ukrainian Artemia reflects a very young populations that diverged about 196,000 years ago. Palaeoecological evidence suggests that the age of the major habitat of A. urmiana i.e. Urmia Lake goes back to the Tertiary Period while the Ukranian habitats of the species are very young, by virtue of geological features of the Holocene age. We conclude that the biogeographical origin of A. urmiana is outside of Europe and the current state of knowledge strongly suggests that Urmia Lake has been the major source of its expansion into its modern habitats in Europe.

  9. Protective efficacy of the antioxidants vitamin E and Trolox against Microcystis aeruginosa and microcystin-LR in Artemia franciscana nauplii.

    PubMed

    Ruebhart, David R; Wickramasinghe, Wasantha; Cock, Ian E

    2009-01-01

    This study was undertaken to evaluate the protective efficacy of the antioxidants vitamin E and Trolox (a water-soluble vitamin E derivative) against the toxicity of microcystin-LR (MC-LR), Microcystis aeruginosa aqueous extract (CE), and a reference toxin, menadione sodium bisulfite (MSB), in Artemia franciscana nauplii. This was achieved by using the well-established brine shrimp bioassay. The experiment was conducted in 2 stages, with (1) 12-h mortality time course and (2) LC50 determination for 12- and 24-h exposures. Treatments consisted of MC-LR, CE, and MSB alone and with 4-h pretreatments of either vitamin E or Trolox. Sensitivity of A. franciscana nauplii with 24-h LC50 values of 11 (10.1-12.1) microg/ml for MSB and 9.5 (8.8-10.4) microg/ml for MC-LR were in general agreement with values reported for Artemia sp. Both antioxidant pretreatments resulted in significant reductions in mortality of approximately 50% at 9 h postexposure when challenged by either 40 microg/ml MC-LR or 20 microg/ml MSB. In contrast, the antioxidant pretreatments offered little to no protection from CE, suggesting that other uncharacterized bioactive compounds contributed to overall toxicity. The described bioassay is easily accessible, inexpensive, rapid, and complies with animal ethics guidelines of many countries, and thus provides a potential alternative to the mouse bioassay for the initial screening for chemoprotectants against MC-LR toxicity.

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2015-08-27

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

  12. A first AFLP-based genetic linkage map for brine shrimp Artemia franciscana and its application in mapping the sex locus.

    PubMed

    De Vos, Stephanie; Bossier, Peter; Van Stappen, Gilbert; Vercauteren, Ilse; Sorgeloos, Patrick; Vuylsteke, Marnik

    2013-01-01

    We report on the construction of sex-specific linkage maps, the identification of sex-linked markers and the genome size estimation for the brine shrimp Artemia franciscana. Overall, from the analysis of 433 AFLP markers segregating in a 112 full-sib family we identified 21 male and 22 female linkage groups (2n = 42), covering 1,041 and 1,313 cM respectively. Fifteen putatively homologous linkage groups, including the sex linkage groups, were identified between the female and male linkage map. Eight sex-linked AFLP marker alleles were inherited from the female parent, supporting the hypothesis of a WZ-ZZ sex-determining system. The haploid Artemia genome size was estimated to 0.93 Gb by flow cytometry. The produced Artemia linkage maps provide the basis for further fine mapping and exploring of the sex-determining region and are a possible marker resource for mapping genomic loci underlying phenotypic differences among Artemia species.

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

    PubMed

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-02-09

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

  14. Oxidative stress is a mediator for increased lipid accumulation in a newly isolated Dunaliella salina strain.

    PubMed

    Yilancioglu, Kaan; Cokol, Murat; Pastirmaci, Inanc; Erman, Batu; Cetiner, Selim

    2014-01-01

    Green algae offer sustainable, clean and eco-friendly energy resource. However, production efficiency needs to be improved. Increasing cellular lipid levels by nitrogen depletion is one of the most studied strategies. Despite this, the underlying physiological and biochemical mechanisms of this response have not been well defined. Algae species adapted to hypersaline conditions can be cultivated in salty waters which are not useful for agriculture or consumption. Due to their inherent extreme cultivation conditions, use of hypersaline algae species is better suited for avoiding culture contamination issues. In this study, we identified a new halophilic Dunaliella salina strain by using 18S ribosomal RNA gene sequencing. We found that growth and biomass productivities of this strain were directly related to nitrogen levels, as the highest biomass concentration under 0.05 mM or 5 mM nitrogen regimes were 495 mg/l and 1409 mg/l, respectively. We also confirmed that nitrogen limitation increased cellular lipid content up to 35% under 0.05 mM nitrogen concentration. In order to gain insight into the mechanisms of this phenomenon, we applied fluorometric, flow cytometric and spectrophotometric methods to measure oxidative stress and enzymatic defence mechanisms. Under nitrogen depleted cultivation conditions, we observed increased lipid peroxidation by measuring an important oxidative stress marker, malondialdehyde and enhanced activation of catalase, ascorbate peroxidase and superoxide dismutase antioxidant enzymes. These observations indicated that oxidative stress is accompanied by increased lipid content in the green alga. In addition, we also showed that at optimum cultivation conditions, inducing oxidative stress by application of exogenous H2O2 leads to increased cellular lipid content up to 44% when compared with non-treated control groups. Our results support that oxidative stress and lipid overproduction are linked. Importantly, these results also suggest that

  15. Map showing drainage basins and historic cloudburst floods in the Salina quadrangle, Utah

    USGS Publications Warehouse

    Hackman, Robert J.; Williams, Paul L.

    1972-01-01

    In the Salina quadrangle, as in most of the arid West, summer precipitation commonly occurs as thunderstorms. Suring these storms, rain falls as a torrential downpour, or cloudburst, in a local area. An inch of rain or more may fall in half an hour; U.S. Weather Bureau records show that o.4 inch of rain has fallen in a period of 5 minutes (Woolley, 1946). Such a fall of water far exceeds the absorptive capacity of the ground surface, and in areas of steep sparsely vegetated terrain the runoff forms a cloudburst flood in which loose rock, soil, and alluvium combine with water to form a debris-laden mudflow. The mudflow then moves rapidly down gullies and canyons with power great enough to erode and to transport debris, and to destroy the works of man lying in its path. When the mudflow pours from the canyon mount into an open valley, solid debris separates from the water and is added to the alluvial fan built by numerous previous floods. Because many towns in Utah are built on fans at the mouths of canyons, there has been loss of life and considerable damage to buildings, streets, and crops since 1847, when white men first settled in Utah.This map shows historical cloudburst floods for which records exist; data were taken from the sources listed below. Most of the flooded areas shown are in or near populated places, and so the floods were observed and recorded. Actually, no part of the quadrangle is exempt from cloudburst floods; every canyon, dry wash, and swale is visited sooner or later by a cloudburst and becomes, briefly, the site of a destructive mudflow. The traveler is advised to exercise caution in all drainageways, especially during July and August, when 80 percent of the cloudbursts occur.

  16. Sedimentation in Michigan basin during earliest Salina: evidence for an excursion from eustacy

    SciTech Connect

    Cercone, K.R.

    1986-08-01

    A basal A-1 evaporite member of the Upper Silurian Salina Group, a marine evaporite sequence, appears to record a time of lowered sea level in the Michigan basin. Indicators of shallow sabkha deposition, such as nodular anhydrite and nonplanar stromatolites, occur in parts of the A-1 evaporite. This unit also contains scattered nodules of borate, a nonmarine evaporite, and the bittern salt sylvite. The petrologic evidence for lowered sea level is supported by studies showing that Middle Silurian reefal buildups within the Michigan basin were subaerially exposed during or immediately prior to A-1 evaporite deposition. However, other studies concluded that carbonate platforms in Indiana and Illinois continued to host flourishing Silurian reef communities throughout A-1 evaporite deposition, under conditions of high global sea levels. The conflicting evidence can be resolved only by postulating that the Michigan basin became isolated from surrounding epeiric seas during A-1 evaporite deposition. Tidal and peritidal carbonates - the Greenfield, Limberlost, Sugar Run, and Engadine dolomites - were deposited at the edge of the Michigan basin during this time. These units could have served both as sills and as shorelines that separated open epeiric seas from a partly desiccated basin. Evaporating brines, pooled below sea level in the basin, could have been replenished by seawater and meteoric water flowing through shallow inlets or seeping into the basin through the subsurface. Basin isolation may have been enhanced by minor eustatic fluctuations in sea level and by the constraints on shallow-water circulation in epeiric seas. Therefore, in analogy to the Miocene desiccation of the Mediterranean, the large apparent drop in sea level recorded by the A-1 evaporite would have been a local rather than a eustatic change.

  17. Habitat of oil in the Lindsborg field, Salina basin, north-central Kansas

    SciTech Connect

    Newell, K.D. )

    1991-03-01

    The Lindsborg field was discovered in 1938, and is now 14 mi in length and 1-2 mi in width. It has a projected ultimate recovery of 16 MMBO. Three pay zones (5-20 ft thick) produce in the field. The Simpson pay zone (Middle Ordovician) is a well-rounded, quartzitic sandstone that is interpreted to be a paralic, high-energy shelf deposit. The Viola pay (Middle Ordovician) appears to be a dolomitic, lime grainstone but no cores are available to confirm this. The uppermost pay zone, the Upper Ordovician Maquoketa, is a finely laminated, vuggy, cherry dolomite interpreted to have been deposited as a subtidal lime mudstone in a restricted lagoon. The Simpson and Viola pays are structurally trapped in culminations along the crest of the Lindsborg anticline. Although the Maquoketa pay is structurally trapped with the other pay zones in the southern half of the field, its locus of production in the north half of the fields extends 100 ft vertically down the western flank of the anticline. The trapping mechanism is unclear due to lack of core control and modern logging suites, but it may be subtle updip diagenetic change from vuggy to nonvuggy dolomite. The Simpson and Maquoketa oils are geochemically distinct. Both may reflect efficient local source-to-reservoir migration from originally rich but marginally mature Ordovician and Devonian shales that contact each pay zone. If oil in the Lindsborg field is locally generated, the prospectivity of the relatively unproductive and underexplored Salina basin may be enhanced.

  18. Predatory cannibalism in Drosophila melanogaster larvae.

    PubMed

    Vijendravarma, Roshan K; Narasimha, Sunitha; Kawecki, Tadeusz J

    2013-01-01

    Hunting live prey is risky and thought to require specialized adaptations. Therefore, observations of predatory cannibalism in otherwise non-carnivorous animals raise questions about its function, adaptive significance and evolutionary potential. Here we document predatory cannibalism on larger conspecifics in Drosophila melanogaster larvae and address its evolutionary significance. We found that under crowded laboratory conditions younger larvae regularly attack and consume 'wandering-stage' conspecifics, forming aggregations mediated by chemical cues from the attacked victim. Nutrition gained this way can be significant: an exclusively cannibalistic diet was sufficient for normal development from eggs to fertile adults. Cannibalistic diet also induced plasticity of larval mouth parts. Finally, during 118 generations of experimental evolution, replicated populations maintained under larval malnutrition evolved enhanced propensity towards cannibalism. These results suggest that, at least under laboratory conditions, predation on conspecifics in Drosophila is a functional, adaptive behaviour, which can rapidly evolve in response to nutritional conditions.

  19. Undescribed Setae in Larvae of Culicidae (Diptera)

    DTIC Science & Technology

    1974-03-01

    ABSTRACT. An unnamed pair of setae (two pairs in some species groups) on the larval cervical membrane in all genera of Culicidae examined is des- cribed...ventrolat- era1 seta was noted on the cervical membrane by the senior author. Further research confirmed its presence in all culicid genera for...referred to them as cervical hairs and recorded their length and branching in third and fourth stage larvae of the four Aedes species he studied

  20. Zebrafish fed on recombinant Artemia expressing epinecidin-1 exhibit increased survival and altered expression of immunomodulatory genes upon Vibrio vulnificus infection.

    PubMed

    Jheng, Yu-Hsuan; Lee, Lin-Han; Ting, Chen-Hung; Pan, Chieh-Yu; Hui, Cho-Fat; Chen, Jyh-Yih

    2015-01-01

    Artemia has been used extensively in aquaculture as fodder for larval fish, shrimp, and shellfish. Epinecidin-1, an antimicrobial peptide, was isolated from grouper (Epinephelus coioides) in 2005. Epinecidin-1 has been previously reported to possess antimicrobial activity against several Gram-positive and Gram-negative bacterial species, including Staphylococcus coagulase, Pseudomonas aeruginosa, Streptococcus pyogenes, and Vibrio vulnificus. In this study, we used electroporation to introduce plasmid DNA encoding a green fluorescent protein (EGFP)-epinecidin-1 fusion protein under the control of the cytomegalovirus (CMV) promoter into decapsulated Artemia cysts. Optimization of various properties (including cyst weight (0.2 g), plasmid concentration (50 μg/100 μl), and pulse voltage (150 V), length (10 ms), and number (2)) resulted in a hatching rate of 41.15%, a transfection efficiency of 49.81%, and a fluorescence intensity (A.U.) of 47.46. The expression of EGFP-epinecidin-1 was first detected by quantitative RT-PCR at 120 h post-electroporation, and protein was identified by Western blot at the same time. Furthermore, the EGFP-epinecidin-1 protein inhibited V. vulnificus (204) growth, as demonstrated by zone of inhibition studies. Zebrafish fed on transgenic Artemia expressing CMV-gfp-epi combined with commercial fodder were more resistant to infection by V. vulnificus (204): survival rate was enhanced by over 70% at 7, 14, and 21 days post-infection, and bacterial numbers in the liver and intestine were reduced. In addition, feeding of transgenic Artemia to zebrafish affected the immunomodulatory response to V. vulnificus (204) infection; expression of immune-responsive genes, including hepcidin and defbl2, was altered, as shown by qPCR. These findings suggest that feeding transgenic Artemia expressing CMV-gfp-epi to larval fish has antimicrobial effects, without the drawbacks of introducing drug residues or inducing bacterial drug resistance.

  1. Visual learning in individually assayed Drosophila larvae.

    PubMed

    Gerber, B; Scherer, S; Neuser, K; Michels, B; Hendel, T; Stocker, R F; Heisenberg, M

    2004-01-01

    An understanding of associative learning is facilitated if it can be analyzed in a simple animal like the fruit fly Drosophila. Here, we introduce the first visual associative learning paradigm for larval Drosophila; this is remarkable as larvae have an order of magnitude fewer neurons than adult flies. Larvae were subjected to either of two reciprocal training regimes: Light+/Dark- or Light-/Dark+. Subsequently, all larvae were individually tested for their preference between Light versus Dark. The difference between training regimes was therefore exclusively which visual situation was associated with which reinforcer; differences observed during the test thus reflected exclusively associative learning. For positive reinforcement (+) we used fructose (FRU), and for negative reinforcement (-) either quinine or sodium chloride (QUI, NaCl). Under these conditions, associative learning could be reproducibly observed in both wild-type strains tested. We then compared the effectiveness of training using differential conditioning, with both positive and negative reinforcement, to that using only positive or only negative reinforcement. We found that FRU only, but neither QUI nor NaCl, was in itself effective as a reinforcer. This is the first demonstration of appetitive learning in larval Drosophila. It is now possible to investigate the behavioral and neuronal organization of appetitive visual learning in this simple and genetically easy-to-manipulate experimental system.

  2. Caffeine Taste Signaling in Drosophila Larvae

    PubMed Central

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

    2016-01-01

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

  3. High-EPA Biomass from Nannochloropsis salina Cultivated in a Flat-Panel Photo-Bioreactor on a Process Water-Enriched Growth Medium

    PubMed Central

    Safafar, Hamed; Hass, Michael Z.; Møller, Per; Holdt, Susan L.; Jacobsen, Charlotte

    2016-01-01

    Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry. PMID:27483291

  4. High-EPA Biomass from Nannochloropsis salina Cultivated in a Flat-Panel Photo-Bioreactor on a Process Water-Enriched Growth Medium.

    PubMed

    Safafar, Hamed; Hass, Michael Z; Møller, Per; Holdt, Susan L; Jacobsen, Charlotte

    2016-07-29

    Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry.

  5. Quiescence in Artemia franciscana embryos: reversible arrest of metabolism and gene expression at low oxygen levels.

    PubMed

    Hand, S C

    1998-04-01

    Depression of the production and consumption of cellular energy appears to be a prerequisite for the survival of prolonged bouts of anoxia. A correlation exists between the degree of metabolic depression under anoxia and the duration of anoxia tolerance. In the case of brine shrimp (Artemia franciscana) embryos, oxygen deprivation induces a reversible quiescent state that can be tolerated for several years with substantial survivorship. A global arrest of cytoplasmic translation accompanies the transition into anoxia, and rates of protein synthesis in mitochondria from these embryos appears to be markedly reduced in response to anoxia. Previous evidence suggests that the acute acidification of intracellular pH (pHi) by over 1.0 unit during the transition into anoxia contributes to the depression of biosynthesis, but message limitation does not appear to play a role in the down-regulation in either cellular compartment. The ontogenetic increase in mRNA levels for a mitochondrial-encoded subunit of cytochrome c oxidase (COX I) and for nuclear-encoded actin is blocked by anoxia and aerobic acidosis (artificial quiescence imposed by intracellular acidification under aerobic conditions). Further, the levels of COX I and actin mRNA do not decline appreciably during 6 h bouts of quiescence, even though protein synthesis is acutely arrested across this same period. Thus, the constancy of mRNA levels during quiescence indicates that reduced protein synthesis is not caused by message limitation but, instead, is probably controlled at the translational level. This apparent stabilization of mRNA under anoxia is mirrored in an extension of protein half-life. The ubiquitin-dependent pathway for protein degradation is depressed under anoxia and aerobic acidosis, as judged by the acute drop in levels of ubiquitin-conjugated proteins. Mitochondrial protein synthesis is responsive to both acidification of pHi and removal of oxygen per se. Matrix pH declines in parallel with pHi, and

  6. Effects of copper, cadmium, and zinc on the hatching success of brine shrimp (Artemia franciscana).

    PubMed

    Brix, K V; Gerdes, R M; Adams, W J; Grosell, M

    2006-11-01

    Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28 microg l-1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14 microg l-1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were either biased low as a result of an artifact of the test method used or that site-specific water-quality conditions in the lake had decreased metal bioavailability such that brine shrimp could successfully reproduce. To test these hypotheses, we initiated a step-wise series of experiments. First we investigated the effects of pretreatment of brine shrimp cysts with antibiotics on brine shrimp sensitivity to metals because previous investigators as part of their test methods have used antibiotics. Next we considered the effect of ionic composition of the artificial test media on sensitivity. Finally, we evaluated the effects of the site-specific water quality of the GSL on metal bioavailability and toxicity. Results indicate that pretreatment of cysts with antibiotics had no effect on sensitivity. However, we were unable to repeat the previous values for Cd and Zn, obtaining EC50s of 11,859 and 289 microg l-1 for Cd and Zn, respectively. For Cu, however, we estimated an EC50 of 12 microg l-1, so we conducted further testing on the artificial media, adjusting the media composition to better reflect the Ca2+ and HCO3- concentration of normal seawater. This increased the EC50

  7. Detrimental effect of CO2-driven seawater acidification on a crustacean brine shrimp, Artemia sinica.

    PubMed

    Zheng, Chao-qun; Jeswin, Joseph; Shen, Kai-li; Lablche, Meghan; Wang, Ke-jian; Liu, Hai-peng

    2015-03-01

    The effects of the decline in ocean pH, termed as ocean acidification due to the elevated carbon dioxide in the atmosphere, on calcifying organisms such as marine crustacean are unclear. To understand the possible effects of ocean acidification on the physiological responses of a marine model crustacean brine shrimp, Artemia sinica, three groups of the cysts or animals were raised at different pH levels (8.2 as control; 7.8 and 7.6 as acidification stress according to the predictions for the end of this century and next century accordingly) for 24 h or two weeks, respectively, followed by examination of their hatching success, morphological appearance such as deformity and microstructure of animal body, growth (i.e. body length), survival rate, expression of selected genes (involved in development, immunity and cellular activity etc), and biological activity of several key enzymes (participated in antioxidant responses and physiological reactions etc). Our results clearly demonstrated that the cysts hatching rate, growth at late stage of acidification stress, and animal survival rate of brine shrimp were all reduced due to lower pH level (7.6 & 7.8) on comparison to the control group (pH 8.2), but no obvious change in deformity or microstructure of brine shrimp was present under these acidification stress by microscopy observation and section analysis. In addition, the animals subjected to a lower pH level of seawater underwent changes on their gene expressions, including Spätzle, MyD88, Notch, Gram-negative bacteria binding protein, prophenoloxidase, Apoptosis inhibitor 5, Trachealess, Caveolin-1 and Cyclin K. Meanwhile, several key enzyme activities, including superoxide dismutase, catalase, peroxidase, alkaline phosphatase and acid phosphatase, were also affected by acidified seawater stress. Taken together, our findings supports the idea that CO2-driven seawater acidification indeed has a detrimental effect, in case of hatching success, growth and survival, on

  8. Oxygen and pH regulation of protein synthesis in mitochondria from Artemia franciscana embryos.

    PubMed Central

    Kwast, K E; Hand, S C

    1996-01-01

    To identify factors responsible for the down-regulation of mitochondrial biosynthetic processes during anoxia in encysted Artemia franciscana embryos, the effects of oxygen limitation and pH on protein synthesis were investigated in isolated mitochondria. At the optimal pH of 7.5, exposure of mitochondria to anoxia decreases the protein synthesis rate by 79%. Rates were suppressed by a further 10% at pH 6.8, the intracellular pH (pHi) measured under anoxia in vivo. Matrix pH, measured under identical conditions, was 8.43 +/- 0.01 at an extra-mitochondrial pH of 7.9 (mean +/- S.E.M., n = 3), 8.05 +/- 0.01 at pH 7.5, and 7.10 +/- 0.01 at pH 6.8. The matrix pH did not vary (P > or = 0.20) as a function of oxygen availability during the 1 h assays. Intramitochondrial purine nucleotides varied little as a function of pH. In contrast, after 1 h of protein synthesis under anoxia, ATP levels decreased by up to 40%, whereas AMP, ADP and GDP concentrations increased, and GTP and GMP concentrations remained relatively constant. The addition of 1 mM ATP at the onset of anoxia maintained the ATP/ADP ratio at the aerobic value, but did not stabilized the GTP/GDP ratio or rescue rates of protein synthesis. Thus, at present, we cannot eliminate the possibility that the decrease in the GTP/GDP ratio during anoxia may contribute to the suppression of protein synthesis. The effect of anoxia was reversible; the rate of protein synthesis upon reoxygenation after a 30 min bout of anoxia was comparable (P = 0.14) with the pre-anoxic rate (193 +/- 17 and 174 +/- 6 pmol of leucine per mg of protein respectively, mean +/- S.E.M., n = 3). The array of mitochondrial translation products did not differ qualitatively as a function of either oxygen availability or pH. Finally, similar pH profiles for protein synthesis were obtained with either [3H]leucine or [3H]histidine (known to use different transporters). Consequently, it is improbable that the pH-sensitivity of protein synthesis can be

  9. Drosophila larvae: Thermal ecology in changing environments

    NASA Astrophysics Data System (ADS)

    Wang, George

    Temperature affects almost all aspects of life. Although much work has been done to assess the impact of temperature on organismal performance, relatively little is known about how organisms behaviorally regulate temperature, how these behaviors effect population fitness, or how changing climate may interact with these behaviors. I explore these questions with the model system Drosophila larvae. Larvae are small, with a low thermal mass and limited capacity for physiological thermoregulation. Mortality is generally high in larvae, with large potential impacts on population growth rate. Thus behavioral thermoregulation in larvae should be of critical selective importance. I present a review of the current knowledge of Drosophila thermal preference. I describe quantifiable thermoregulatory behaviors ( TMV and TW) unique to larvae. I show interspecific variation of these behaviors in Drosophila melanogaster and several close relatives, and intraspecific variation between populations collected from different environments. I also investigate these behaviors in two mutant lines, ssa and biz, to investigate the genetic basis of these behaviors. I show that larval thermoregulatory systems are independent of those of adults. Further these thermoregulatory behaviors differ between two sister species, D. yakuba and D. santomea. Although these two species readily hybridize in laboratory conditions, very few hybrids are observed in the field. The surprising result that hybrids of D. yakuba and D. santomea seem to inherit TMV from D. yakuba suggests a novel extrinsic isolation mechanism between the two species. I explore how fitness is the result of the interaction between genetics and the environment. I utilize Monte Carlo simulation to show how non-linear norms of reaction generate variation in populations even in the absence of behavior or epigenetic evolutionary mechanisms. Finally I investigate the global distribution of temperatures in which these organisms exist using

  10. Interactions among Drosophila larvae before and during collision

    PubMed Central

    Otto, Nils; Risse, Benjamin; Berh, Dimitri; Bittern, Jonas; Jiang, Xiaoyi; Klämbt, Christian

    2016-01-01

    In populations of Drosophila larvae, both, an aggregation and a dispersal behavior can be observed. However, the mechanisms coordinating larval locomotion in respect to other animals, especially in close proximity and during/after physical contacts are currently only little understood. Here we test whether relevant information is perceived before or during larva-larva contacts, analyze its influence on behavior and ask whether larvae avoid or pursue collisions. Employing frustrated total internal reflection-based imaging (FIM) we first found that larvae visually detect other moving larvae in a narrow perceptive field and respond with characteristic escape reactions. To decipher larval locomotion not only before but also during the collision we utilized a two color FIM approach (FIM2c), which allowed to faithfully extract the posture and motion of colliding animals. We show that during collision, larval locomotion freezes and sensory information is sampled during a KISS phase (german: Kollisions Induziertes Stopp Syndrom or english: collision induced stop syndrome). Interestingly, larvae react differently to living, dead or artificial larvae, discriminate other Drosophila species and have an increased bending probability for a short period after the collision terminates. Thus, Drosophila larvae evolved means to specify behaviors in response to other larvae. PMID:27511760

  11. The potential role of As-sumo-1 in the embryonic diapause process and early embryo development of Artemia sinica.

    PubMed

    Chu, Bing; Yao, Feng; Cheng, Cheng; Wu, Yang; Mei, Yanli; Li, Xuejie; Liu, Yan; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

    2014-01-01

    During embryonic development of Artemia sinica, environmental stresses induce the embryo diapause phenomenon, required to resist apoptosis and regulate cell cycle activity. The small ubiquitin-related modifier-1 (SUMO), a reversible post-translational protein modifier, plays an important role in embryo development. SUMO regulates multiple cellular processes, including development and other biological processes. The molecular mechanism of diapause, diapause termination and the role of As-sumo-1 in this processes and in early embryo development of Artemia sinica still remains unknown. In this study, the complete cDNA sequences of the sumo-1 homolog, sumo ligase homolog, caspase-1 homolog and cyclin B homolog from Artemia sinica were cloned. The mRNA expression patterns of As-sumo-1, sumo ligase, caspase-1, cyclin B and the location of As-sumo-1 were investigated. SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E proteins were analyzed during different developmental stages of the embryo of A. sinica. Small interfering RNA (siRNA) was used to verify the function of sumo-1 in A. sinica. The full-length cDNA of As-sumo-1 was 476 bp, encoding a 92 amino acid protein. The As-caspases-1 cDNA was 966 bp, encoding a 245 amino-acid protein. The As-sumo ligase cDNA was 1556 bp encoding, a 343 amino acid protein, and the cyclin B cDNA was 739 bp, encoding a 133 amino acid protein. The expressions of As-sumo-1, As-caspase-1 and As-cyclin B were highest at the 10 h stage of embryonic development, and As-sumo ligase showed its highest expression at 0 h. The expression of As-SUMO-1 showed no tissue or organ specificity. Western blotting showed high expression of As-SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E at the 10 h stage. The siRNA caused abnormal development of the embryo, with increased malformation and mortality. As-SUMO-1 is a crucial regulation and modification protein resumption of embryonic diapause and early embryo development of A. sinica.

  12. Transcriptional Response of Honey Bee Larvae Infected with the Bacterial Pathogen Paenibacillus larvae

    PubMed Central

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

    2013-01-01

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

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

    PubMed

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

    2015-01-01

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

  14. The Identification of Congeners and Aliens by Drosophila Larvae

    PubMed Central

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

    2015-01-01

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

  15. Evaluation of Culture Conditions to Obtain Fatty Acids from Saline Microalgae Species: Dunaliella salina, Sinecosyfis sp., and Chroomonas sp.

    PubMed Central

    Castilla Casadiego, D. A.; Albis Arrieta, A. R.; Angulo Mercado, E. R.; Cervera Cahuana, S. J.; Baquero Noriega, K. S.; Suárez Escobar, A. F.; Morales Avendaño, E. D.

    2016-01-01

    The use of the saline microalgae, Dunaliella salina, Sinecosyfis sp., and Chroomonas sp., was explored as an alternative source for the production of fatty acids using fertilizer and glycerol as culture media. The nutrient medium used contained “Nutrifoliar,” a commercial fertilizer, and/or glycerol, in natural sea water. The microalgae were placed in cultures with different conditions. The parameters that favored the largest production of fatty acids were 24 hours of agitation and illumination, 1620 L/day of air supply, 2.25 L of air/min, and a temperature of 32°C using “Nutrifoliar” as the culture media. Results indicated that, from 3 g of microalgae in wet base of Chroomonas sp., 54.43 mg of oil was produced. The chromatographic characterization of oil obtained revealed the presence of essential fatty acids such as 9,12,15-octadecatrienoic acid (omega-3) and 4,7,10-hexadecatrienoic acid (omega-6) from the species Dunaliella salina. On the other hand, 9,12-octadecadienoic acid (omega-6) and cis-11-eicosenoic acid (omega-9) were identified from the species Chroomonas sp. The temperature variations played an important role in the velocity of growth or the production of the algae biomass, the amount of oil, and the ability to produce fatty acids. PMID:27376085

  16. TFA and EPA Productivities of Nannochloropsis salina Influenced by Temperature and Nitrate Stimuli in Turbidostatic Controlled Experiments

    PubMed Central

    Hoffmann, Maren; Marxen, Kai; Schulz, Rüdiger; Vanselow, Klaus Heinrich

    2010-01-01

    The influence of different nitrate concentrations in combination with three cultivation temperatures on the total fatty acids (TFA) and eicosapentaenoic acid (EPA) content of Nannochloropsis salina was investigated. This was done by virtue of turbidostatic controlled cultures. This control mode enables the cultivation of microalgae under defined conditions and, therefore, the influence of single parameters on the fatty acid synthesis of Nannochloropsis salina can be investigated. Generally, growth rates decreased under low nitrate concentrations. This effect was reinforced when cells were exposed to lower temperatures (from 26 °C down to 17 °C). Considering the cellular TFA concentration, nitrate provoked an increase of TFA under nitrate limitation up to 70% of the biological dry mass (BDM). In contrast to this finding, the EPA content decreased under low nitrate concentrations. Nevertheless, both TFA and EPA contents increased under a low culture temperature (17 °C) compared to moderate temperatures of 21 °C and 26 °C. In terms of biotechnological production, the growth rate has to be taken into account. Therefore, for both TFA and EPA production, a temperature of 17 °C and a nitrate concentration of 1800 μmol L−1 afforded the highest productivities. Temperatures of 21 °C and 26 °C in combination with 1800 μmol L−1 nitrate showed slightly lower TFA and EPA productivities. PMID:20948904

  17. Evaluation of Culture Conditions to Obtain Fatty Acids from Saline Microalgae Species: Dunaliella salina, Sinecosyfis sp., and Chroomonas sp.

    PubMed

    Castilla Casadiego, D A; Albis Arrieta, A R; Angulo Mercado, E R; Cervera Cahuana, S J; Baquero Noriega, K S; Suárez Escobar, A F; Morales Avendaño, E D

    2016-01-01

    The use of the saline microalgae, Dunaliella salina, Sinecosyfis sp., and Chroomonas sp., was explored as an alternative source for the production of fatty acids using fertilizer and glycerol as culture media. The nutrient medium used contained "Nutrifoliar," a commercial fertilizer, and/or glycerol, in natural sea water. The microalgae were placed in cultures with different conditions. The parameters that favored the largest production of fatty acids were 24 hours of agitation and illumination, 1620 L/day of air supply, 2.25 L of air/min, and a temperature of 32°C using "Nutrifoliar" as the culture media. Results indicated that, from 3 g of microalgae in wet base of Chroomonas sp., 54.43 mg of oil was produced. The chromatographic characterization of oil obtained revealed the presence of essential fatty acids such as 9,12,15-octadecatrienoic acid (omega-3) and 4,7,10-hexadecatrienoic acid (omega-6) from the species Dunaliella salina. On the other hand, 9,12-octadecadienoic acid (omega-6) and cis-11-eicosenoic acid (omega-9) were identified from the species Chroomonas sp. The temperature variations played an important role in the velocity of growth or the production of the algae biomass, the amount of oil, and the ability to produce fatty acids.

  18. Sannastatin, a novel toxic macrolactam polyketide glycoside produced by actinomycete Streptomyces sannanensis.

    PubMed

    Yang, Sheng-Xiang; Gao, Jin-Ming; Zhang, An-Ling; Laatsch, Hartmut

    2011-07-01

    A new rare 20-membered macrocyclic lactam incorporating a diene conjugated olefin, designated sannastatin (1), together with the known structurally related vicenistatin (2), has been isolated from the cultures of Streptomyces sannanensis, a bacteria found in the feces of Ailuropoda melanoleuca. The structure of the new compound was established on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR ((1)H-(1)H COSY, TOCSY, HSQC, HMBC, and NOESY) experiments. Compounds 1 and 2 displayed significant growth inhibitory activity against the brine shrimp (Artemia salina) larvae.

  19. Phenolic dimers and an indole alkaloid from Campylospermum flavum (Ochnaceae).

    PubMed

    Ndongo, Joseph Thierry; Shaaban, Mohamed; Mbing, Joséphine Ngo; Bikobo, Dominique Ngono; Atchadé, Alex de Théodore; Pegnyemb, Dieudonné Emmanuel; Laatsch, Hartmut

    2010-11-01

    From the leaves and stem bark of Campylospermum flavum (Ochnaceae), three compounds, namely 4‴-O-methylagathisflavone, flavumchalcone, and flavumindole have been isolated together with 10 known compounds, including three flavonoids, two biflavonoids, two alkaloids, two nitrile glucosides, and glucopyranosyl-β-sistosterol. The structures of these compounds and their relative configurations were established by 1D and 2D NMR experiments. The methanolic crude extracts of leaves and stem bark of C. flavum and compounds displayed a significant cytotoxicity towards Artemia salina larvae.

  20. Spawning and rearing Atlantic menhaden

    SciTech Connect

    Hettler, W.F.

    1981-04-01

    Two-year-old Atlantic menhaden (Brevoortia tyrannus) held in the laboratory at ambient temperatures and salinities for more than 1 year, were induced to spawn by injecting first human chorionic gonadotropin and then carp pituitary powder. Spawning took place at temperatures of 16 to 20/sup 0/C in a 2100-L indoor tank modified to recover the buoyant fertilized eggs. Larvae were reared to the juvenile stage on a diet of cultured rotifers (Brachionus plicatilus), sieved wild zooplankton (64 to 500 ..mu..m), brine shrimp (Artemia salina) nauplii, and powdered trout food.

  1. Self-mixing of fly larvae during feeding

    NASA Astrophysics Data System (ADS)

    Shishkov, Olga; Johnson, Christopher; Zhang, Bryan; Hu, David

    2016-11-01

    How do we sustainably feed a growing world population? One solution of increasing interest is the use of black solider fly larvae, pea-sized grubs envisioned to transform hundreds of tons of food waste into a sustainable protein source. Although startups across the world are raising these larvae, a physical understanding of how they should be raised and fed remains missing. In this study, we present experiments measuring their feeding rate as a function of number of larvae. We show that larger groups of larvae have greater mixing which entrains hungry larvae around the food, increasing feeding rate. Feeding of larvae thus differs from feeding of cattle or other livestock which exhibit less self-mixing.

  2. Equipment for transporting live black fly larvae (Diptera: Simuliiae)

    USGS Publications Warehouse

    Tarshis, I.B.; Adkins, T.R.

    1971-01-01

    In studies relating to the biology and ecology of black flies, live larvae of at least 70 species of Simuliidae have been collected from their natural breeding sites and transported in containers with nonagitated water for short distances to the laboratory. One of us (Tarshis 1966) found, however, that even small numbers of simuliid larvae cannot survive in containers with nonagitated water for more than 6 hr. Additionally, when massive numbers of larvae are introduced into transport containers in which the water is not agitated, the larvae perish because they become entangled within the masses of silken threads they emit whenever disturbed (Tarshis and Neil 1970). Therefore, when transporting larvae long distances or when transporting large numbers of larvae any distance, it is essential to agitate the water in the transport containers.

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

    PubMed

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

    2016-09-15

    A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (<10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment.

  4. A serum response factor homologue is expressed in ectodermal tissues during development of the crustacean Artemia franciscana.

    PubMed

    Casero, M C; Sastre, L

    2000-09-01

    Complementary DNA clones have been isolated from the crustacean Artemia franciscana coding for a serum response factor (SRF)-homologue that is more than 96% identical to human and Drosophila melanogaster SRFs in their MADS boxes. The SRF homologue is expressed in ectodermal tissues, as determined by in situ hybridization experiments. A SRF-binding site has been identified in the promoter region of the Actin403 gene that is also expressed in ectodermal tissues, in accordance with its transcriptional regulation by the SRF homologue. The mRNA coding for A. franciscana SRF is present at similar levels in cryptobiotic encysted embryos and in developing nauplii. However, there is a significant increase in CArG-binding activity at the later developmental stage, indicating a postranscriptional regulation of SRF during A. franciscana embryonic development.

  5. Lethal and sublethal endpoints observed for Artemia exposed to two reference toxicants and an ecotoxicological concern organic compound.

    PubMed

    Manfra, Loredana; Canepa, Sara; Piazza, Veronica; Faimali, Marco

    2016-01-01

    Swimming speed alteration and mortality assays with the marine crustacean Artemia franciscana were carried out. EC50 and LC50 values after 24-48h exposures were calculated for two reference toxicants, copper sulphate pentahydrate (CuSO4·5H2O) and Sodium Dodecyl Sulphate (SDS), and an ecotoxicological concern organic compound, Diethylene Glycol (DEG). Different end-points have been evaluated, in order to point out their sensitivity levels. The swimming speed alteration (SSA) was compared to mortality values and also to the hatching rate inhibition (literature data). SSA resulted to be more sensitive than the mortality and with a sensitivity comparable to (or even higher than) the hatching rate endpoint.

  6. Molecular analysis and its expression of a pou homeobox protein gene during development and in response to salinity stress from brine shrimp, Artemia sinica.

    PubMed

    Wang, Jia-Qing; Hou, Lin; Yi, Nan; Zhang, Riu-Feng; Zou, Xiang-Yang

    2012-01-01

    Brine shrimps of the genus Artemia are aquatic species of economic importance because of their important significance to aquaculture and are used as a model species in physiology and developmental biology. Research on Artemia POU homeobox gene function will enhance our understanding of the physiological and developmental processes of POU homeobox gene in animals. Herein, a full-length cDNA encoding an Artemia POU homeobox protein gene 1 (APH-1) from Artemia sinica (designated as As-APH-1) was cloned and characterized by a reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE) method. The As-APH-1 gene encoded a protein of 388 amino acid polypeptide with a calculated molecular mass of 42.85kDa and an isoelectric point of 6.90 and the protein belongs to the POU III family. Multiple sequence alignments revealed that A. sinica As-APH-1 protein sequence shared a conserved POU homeobox domain with other species. The early and persistent expression of As-APH-1 in the naupliar stages by semi-quantitative RT-PCR and whole-mount embryonic immunohistochemistry suggest that As-APH-1 functions very early in the salt gland and may be required continuously in this organ. Later in development, expression of As-APH-1 begins to dramatically decrease and disappear in salt gland of the sub-adult Artemia. In addition, we also discovered that As-APH-1 increased obviously as the salinity increased, indicating that As-APH-1 might be used as a good indicator of salinity stress. In summary, we are the first to identify the As-APH-1 gene and to determine its gene expression patterns in early embryogenesis stages and in different salinity stress in brine shrimp, A. sinica. The result of expression of As-APH-1 affected by salinity changes will provide us further understanding of the underlying mechanisms of osmoregulation in Artemia early embryonic development.

  7. Learning and memory in zebrafish larvae.

    PubMed

    Roberts, Adam C; Bill, Brent R; Glanzman, David L

    2013-01-01

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

  8. Learning and memory in zebrafish larvae

    PubMed Central

    Roberts, Adam C.; Bill, Brent R.; Glanzman, David L.

    2013-01-01

    Larval zebrafish possess several experimental advantages for investigating the molecular and neural bases of learning and memory. Despite this, neuroscientists have only recently begun to use these animals to study memory. However, in a relatively short period of time a number of forms of learning have been described in zebrafish larvae, and significant progress has been made toward their understanding. Here we provide a comprehensive review of this progress; we also describe several promising new experimental technologies currently being used in larval zebrafish that are likely to contribute major insights into the processes that underlie learning and memory. PMID:23935566

  9. Toxicity of phenol on Macrobrachium rosenbergii (de Man) eggs, larvae, and post-larvae

    SciTech Connect

    Law, A.T.; Yeo, M.E.

    1997-03-01

    Literature on the toxicities of phenol on aquatic organisms is very limited. USEPA reported that the acute and chronic toxicities of phenol to freshwater aquatic life occur at concentrations as low as 10.2 mg/L and 2.56 mg/L, respectively. While for the saltwater aquatic life the acute toxicity occurs at concentrations as low as 5.8 mg/L. No data are available for the chronic toxicity of phenol to saltwater aquatic life. Sublethal concentrations of phenol have significant effects on the physiological and histological processes of the aquatic organisms: such as gill necrosis; destruction of erythrocyte cells; inhibition of sexual activities; suppression on growth and reduction of resistance to diseases. Macrobrachium rosenbergii(de Man) is the sole freshwater prawn cultured in Malaysia. Occasionally, the hatcheries are unable to produce the post-larvae because of undefined pollutants present in the water supplies. It has been observed that the use of cracked fiberglass tanks for larvae rearing is correlated with high mortality. This high mortality is probably due to the toxicity of the phenolic compounds which are leached out from the fiber glass tank into the water. This study was undertaken to evaluate the toxicity of phenol on eggs, larvae and post-larvae of M. rosenbergii and to set the water quality criteria of phenol for the said species. 16 refs., 3 tabs.

  10. A Madurella mycetomatis Grain Model in Galleria mellonella Larvae.

    PubMed

    Kloezen, Wendy; van Helvert-van Poppel, Marilyn; Fahal, Ahmed H; van de Sande, Wendy W J

    2015-01-01

    Eumycetoma is a chronic granulomatous subcutaneous infectious disease, endemic in tropical and subtropical regions and most commonly caused by the fungus Madurella mycetomatis. Interestingly, although grain formation is key in mycetoma, its formation process and its susceptibility towards antifungal agents are not well understood. This is because grain formation cannot be induced in vitro; a mammalian host is necessary to induce its formation. Until now, invertebrate hosts were never used to study grain formation in M. mycetomatis. In this study we determined if larvae of the greater wax moth Galleria mellonella could be used to induce grain formation when infected with M. mycetomatis. Three different M. mycetomatis strains were selected and three different inocula for each strain were used to infect G. mellonella larvae, ranging from 0.04 mg/larvae to 4 mg/larvae. Larvae were monitored for 10 days. It appeared that most larvae survived the lowest inoculum, but at the highest inoculum all larvae died within the 10 day observation period. At all inocula tested, grains were formed within 4 hours after infection. The grains produced in the larvae resembled those formed in human and in mammalian hosts. In conclusion, the M. mycetomatis grain model in G. mellonella larvae described here could serve as a useful model to study the grain formation and therapeutic responses towards antifungal agents in the future.

  11. Structure and occurrence of cyphonautes larvae (bryozoa, ectoprocta).

    PubMed

    Nielsen, Claus; Worsaae, Katrine

    2010-09-01

    We have studied larvae of the freshwater ctenostome Hislopia malayensis with scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and LM of serial sections. Some additional observations on larvae of M. membranacea using SEM and CLSM are also reported. The overall configuration of muscles, nerves, and cilia of the two larvae are identical. However, the larva of H. malayensis is much smaller than that of M. membranacea, which may explain most of the differences observed. Although all major nerves and muscle strands are present in H. malayensis, they are generally composed of fewer fibers. The H. malayensis larva lacks the anterior and posterior intervalve cilia. Its pyriform organ is unciliated with only a small central depression. The adhesive epithelium is not invaginated as an adhesive sac and lacks the large muscles interpreted as adhesive sac muscles in the M. membranacea larva. The velum carries two rows of ciliated cells, though the lower "row" consists of only one or two cells. Both rows of ciliated cells are innervated by nerves, which have not been detected in the M. membranacea larva. The ciliated ridge of H. malayensis lacks the frontal cilia. The planktotrophic cyphonautes larvae in a number of ctenostome clades and in the "basal" cheilostome clade Malacostega (and probably in the earliest cheilostomes) support the idea that the cyphonautes larva is the ancestral larval type of the Eurystomata. It may even represent the ancestral larval type of the bryozoans (= ectoprocts).

  12. Chromium (VI) induced oxidative stress in halotolerant alga Dunaliella salina and D. tertiolecta isolated from sambhar salt lake of Rajasthan (India).

    PubMed

    Arun, N; Vidyalaxmi; Singh, D P

    2014-12-24

    Chromium (Cr) is one of the most serious pollutants in aquatic systems. This study was performed to understand the effect of Cr (VI) on halophilic algal strains of D. salina and D. tertiolecta. The results revealed good tolerance of D. salina towards chromium (VI) up to 8 ppm concentration, whereas tolerance level in D. tertiolecta was up to 2 ppm concentration. Cr (VI) not only inhibited the growth of D. tertiolecta, but also showed increased inhibition in the level of photosynthetic pigments, protein and carbohydrate. Results have revealed that chromium (VI) induced higher increase in lipid peroxidation and H2O2 production in D. tertiolecta than the D. salina, particularly at higher concentration of chromium (VI). Chromium (VI) induced increase in the rate of RNO bleaching, loss of pigments and thiol (-SH) group was relatively higher in D. tertiolecta than the D. salina, which is indicating that D. tertiolecta was prone to Cr (VI) induced oxidative stress. Results on RNO bleaching in the presence of radical quenchers suggested that OH° radical played an important role in the chromium (VI)-induced general oxidative stress in D. tertiolecta.

  13. Investigation of environmental factors on the prevalence of free bacteriophages against Shiga toxin-producing Escherichia coli strains in produce pre-harvest environment in Salinas, California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Investigation of environmental factors on the prevalence of free bacteriophages against Shiga toxin-producing Escherichia coli strains in produce pre-harvest environment in Salinas, California Yen-Te Liaoa, Irwin Quintelab, Kimberly Nguyena, Alexandra Salvadora, Michael Cooleya, and Vivian C.H. Wu*a...

  14. A Model of Drosophila Larva Chemotaxis.

    PubMed

    Davies, Alex; Louis, Matthieu; Webb, Barbara

    2015-11-01

    Detailed observations of larval Drosophila chemotaxis have characterised the relationship between the odour gradient and the runs, head casts and turns made by the animal. We use a computational model to test whether hypothesised sensorimotor control mechanisms are sufficient to account for larval behaviour. The model combines three mechanisms based on simple transformations of the recent history of odour intensity at the head location. The first is an increased probability of terminating runs in response to gradually decreasing concentration, the second an increased probability of terminating head casts in response to rapidly increasing concentration, and the third a biasing of run directions up concentration gradients through modulation of small head casts. We show that this model can be tuned to produce behavioural statistics comparable to those reported for the larva, and that this tuning results in similar chemotaxis performance to the larva. We demonstrate that each mechanism can enable odour approach but the combination of mechanisms is most effective, and investigate how these low-level control mechanisms relate to behavioural measures such as the preference indices used to investigate larval learning behaviour in group assays.

  15. Metamorphosis of cinctoblastula larvae (Homoscleromorpha, porifera).

    PubMed

    Ereskovsky, Alexander V; Tokina, Daria B; Bézac, Chantal; Boury-Esnault, Nicole

    2007-06-01

    The metamorphosis of the cinctoblastula of Homoscleromorpha is studied in five species belonging to three genera. The different steps of metamorphosis are similar in all species. The metamorphosis occurs by the invagination and involution of either the anterior epithelium or the posterior epithelium of the larva. During metamorphosis, morphogenetic polymorphism was observed, which has an individual character and does not depend on either external or species specific factors. In the rhagon, the development of the aquiferous system occurs only by epithelial morphogenesis and subsequent differentiation of cells. Mesohylar cells derive from flagellated cells after ingression. The formation of pinacoderm and choanoderm occurs by the differentiation of the larval flagellated epithelium. This is possibly due to the conservation of cell junctions in the external surface of the larval flagellated cells and of the basement membrane in their internal surface. The main difference in homoscleromorph metamorphosis compared with Demospongiae is the persistence of the flagellated epithelium throughout this process and even in the adult since exo- and endopinacoderm remain flagellated. The antero-posterior axis of the larva corresponds to the baso-apical axis of the adult in Homoscleromorpha.

  16. Olfactory Learning in Individually Assayed Drosophila Larvae

    PubMed Central

    Scherer, Sabine; Stocker, Reinhard F.; Gerber, Bertram

    2003-01-01

    Insect and mammalian olfactory systems are strikingly similar. Therefore, Drosophila can be used as a simple model for olfaction and olfactory learning. The brain of adult Drosophila, however, is still complex. We therefore chose to work on the larva with its yet simpler but adult-like olfactory system and provide evidence for olfactory learning in individually assayed Drosophila larvae. We developed a differential conditioning paradigm in which odorants are paired with positive (“+” fructose) or negative (“-” quinine or sodium chloride) gustatory reinforcers. Test performance of individuals from two treatment conditions is compared—one received odorant A with the positive reinforcer and odorant B with a negative reinforcer (A+/B-); animals from the other treatment condition were trained reciprocally (A-/B+). During test, differences in choice between A and B of individuals having undergone either A+/B- or A-/B+ training therefore indicate associative learning. We provide such evidence for both combinations of reinforcers; this was replicable across repetitions, laboratories, and experimenters. We further show that breaks improve performance, in accord with basic principles of associative learning. The present individual assay will facilitate electrophysiological studies, which necessarily use individuals. As such approaches are established for the larval neuromuscular synapse, but not in adults, an individual larval learning paradigm will serve to link behavioral levels of analysis to synaptic physiology. PMID:12773586

  17. Physiological characteristics and stress resistance of great sturgeon (Huso huso) juveniles fed with vitamins C, E, and HUFA-enriched Artemia urmiana nauplii.

    PubMed

    Jalali, Mohammad Ali; Hosseini, Seyed Abbas; Imanpour, Mohammad Reza

    2010-09-01

    This study was carried out to examine the effect of Artemia urmiana nauplii enriched with HUFA, and vitamins C and E on stress tolerance, hematocrit, and biochemical parameters of great sturgeon, Huso huso juveniles. Cod liver oil (EPA 18% and DHA 12%), ascorbyl-6-palmitate and alpha-tocopherol acetate were used as lipid, and vitamin C and E sources, respectively. Beluga juveniles at the stage of first feeding (69.7 +/- 5.9 mg body weight) were randomly divided into five treatments and three tanks were assigned to each diet. All fish groups were fed non-enriched Artemia for the initial 5 days and then fed enriched Artemia for 7 days. Juveniles were fed with Artemia enriched with HUFA + 20% vitamin C (C group); HUFA + 20% vitamin E-enriched Artemia nauplii (E group); HUFA + 20% vitamin C + 20% vitamin E (C and E group); HUFA without vitamins (HUFA) and non-enriched Artemia (control). After the period of enrichment, Juveniles were fed with Daphnia sp. from the 13th to the 40th day. At day 40, the fish were transferred directly from fresh water (0.5 ppt) to brackish water (6 ppt for 4 days and 12 ppt for 2 days) and warm water (from 27 to 33 degrees C) to evaluate juvenile resistance to salinity and thermal shocks. Moreover, all treatments were separately exposed to freshwater in tanks with the same capacity as used for osmotic and thermal tests (as fresh water control). The addition of vitamins C, E, and C + E to HUFA significantly increased fish resistance to 12 ppt salinity and temperature stress tests, whereas survival was not significantly different among challenges at 6 ppt. There was no significant difference in the hematocrit index under stress conditions. Enrichment had significant influence on plasma Na(+) level in the C group on the 4th day at 6 ppt. Na(+) and Ca(2+) concentrations in C, E, and C and E groups on the 1st day at 12 ppt, and Ca(2+) level in E group on the 2nd day at 12 ppt were lower than the other groups. The glucose level in the C and C and

  18. Coupling Between the Changes in CO2 Concentration and Sediment Biogeochemistry in the Salinas De San Pedro Mudflat, California, USA

    NASA Astrophysics Data System (ADS)

    Rezaie Boroon, M.; Diaz, S.; Torres, V.; Lazzaretto, T.; Dehyn, D.

    2013-12-01

    We investigated the effects of elevated carbon dioxide [CO2] on biogeochemistry of marsh sediment including speciation of selected heavy metals in Salinas de San Pedro mudflat in California. The Salinas de San Pedro mudflat has higher carbon (C) content than the vast majority of fully-vegetated salt marshes even with the higher tidal action in the mudflat. Sources for CO2 were identified as atmospheric CO2 as well as due to local fault degassing process. We measured carbon dioxide [CO2], methane [CH4], total organic carbon, dissolved oxygen, salinity, and heavy metal concentration in various salt marsh locations. Overall, our results showed that CO2 concentration ranging from 418.7 to 436.9 [ppm], which are slightly different in various chambers but are in good agreement with some heavy metal concentrations values in mudflat at or around the same location. The selected metal concentration values (ppm) ranging from 0.003 - 0.011(As); 0.001-0.005 (Cd); 0.04-0.02 (Cr); 0.13-0.38 (Cu); 0.11-0.38 (Pb); 0.0009-0.020 (Se); and 0.188-0.321 (Zn). The low dissolved O2 [ppm] in the pore water sediment indicates suboxic environment. Additionally, CO2 [ppm] and loss on ignition (LOI) [%] correlated inversely; the higher CO2 content, the lower was the LOI; that is to say the excess CO2 may caused higher rates of decomposition and therefore it leads to lower soil organic matter (LOI) [%] on the mudflat surface. It appears that the elevated CO2 makes changes in salt marsh pore water chemistry for instance the free ionic metal (Cu2+, Pb2+, etc.) speciation is one of the most reactive form because simply assimilated by the non-decayed or alive organisms in sediment of salt marsh and/or in water. This means that CO2 not only is a sign of improvement in plant productivity, but also activates microbial decomposition through increases in dissolved organic carbon availability. CO2 also increases acidification processes such as anaerobic degradation of microorganism and oxidation of

  19. A case study to optimise and validate the brine shrimp Artemia franciscana immobilisation assay with silver nanoparticles: The role of harmonisation.

    PubMed

    Kos, Monika; Kahru, Anne; Drobne, Damjana; Singh, Shashi; Kalčíková, Gabriela; Kühnel, Dana; Rohit, Rekulapelly; Gotvajn, Andreja Žgajnar; Jemec, Anita

    2016-06-01

    Brine shrimp Artemia sp. has been recognised as an important ecotoxicity and nanotoxicity test model organism for salt-rich aquatic environments, but currently there is still no harmonised testing protocol which would ensure the comparable results for hazard identification. In this paper we aimed to design the harmonised protocol for nanomaterial toxicity testing using Artemia franciscana and present a case study to validate the protocol with silver nanoparticles (AgNPs). We (i) revised the existing nanotoxicity test protocols with Artemia sp. (ii) optimised certain methodological steps based on the experiments with AgNPs and potassium dichromate (K2Cr2O7) as a soluble reference chemical and (iii) tested the optimised protocol in an international inter-laboratory exercise conducted within the EU FP7 NanoValid project. The intra- and inter-laboratory reproducibility of the proposed protocol with a soluble reference chemical K2Cr2O7 was good, which confirms the suitability of this assay for conventional chemicals. However, the variability of AgNPs toxicity results was very high showing again that nanomaterials are inherently challenging for toxicity studies, especially those which toxic effect is linked to shed metal ions. Among the identified sources for this variability were: the hatching conditions, the type of test plate incubation and the illumination regime. The latter induced variations assumingly due to the changes in bioavailable silver species concentrations. Up to our knowledge this is the first inter-laboratory comparison of the Artemia sp. toxicity study involving nanomaterials. Although the inter-laboratory exercise revealed poor repeatability of AgNPs toxicity results, this study provides valuable information regarding the importance of harmonisation of all steps in the test procedure. Also, the presented AgNPs toxicity case study may serve as a platform for further validation steps with other types of NMs.

  20. The small heat shock protein p26 aids development of encysting Artemia embryos, prevents spontaneous diapause termination and protects against stress.

    PubMed

    King, Allison M; MacRae, Thomas H

    2012-01-01

    Artemia franciscana embryos enter diapause as encysted gastrulae, a physiological state of metabolic dormancy and enhanced stress resistance. The objective of this study was to use RNAi to investigate the function of p26, an abundant, diapause-specific small heat shock protein, in the development and behavior of encysted Artemia embryos (cysts). RNAi methodology was developed where injection of Artemia females with dsRNA specifically eliminated p26 from cysts. p26 mRNA and protein knock down were, respectively, confirmed by RT-PCR and immuno-probing of western blots. ArHsp21 and ArHsp22, diapause-related small heat shock proteins in Artemia cysts sharing a conserved α-crystallin domain with p26, were unaffected by injection of females with dsRNA for p26, demonstrating the specificity of protein knock down. Elimination of p26 delayed cyst release from females demonstrating that this molecular chaperone influences the development of diapause-destined embryos. Although development was slowed the metabolic activities of cysts either containing or lacking p26 were similar. p26 inhibited diapause termination after prolonged incubation of cysts in sea water perhaps by a direct effect on termination or indirectly because p26 is necessary for the preservation of diapause maintenance. Cyst diapause was however, terminated by desiccation and freezing, a procedure leading to high mortality within cyst populations lacking p26 and indicating the protein is required for stress tolerance. Cysts lacking p26 were also less resistant to heat shock. This is the first in vivo study to show that knock down of a small heat shock protein slows the development of diapause-destined embryos, suggesting a role for p26 in the developmental process. The same small heat shock protein prevents spontaneous termination of diapause and provides stress protection to encysted embryos.

  1. Expression profiles of miRNAs and involvement of miR-100 and miR-34 in regulation of cell cycle arrest in Artemia.

    PubMed

    Zhao, Ling-Ling; Jin, Feng; Ye, Xiang; Zhu, Lin; Yang, Jin-Shu; Yang, Wei-Jun

    2015-09-01

    Regulation of the cell cycle is complex but critical for proper development, reproduction and stress resistance. To survive unfavourable environmental conditions, the crustacean Artemia produces diapause embryos whose metabolism is maintained at extremely low levels. In the present study, the expression profiles of miRNAs during Artemia diapause entry and termination were characterized using high-throughput sequencing. A total of 13 unclassified miRNAs and 370 miRNAs belonging to 87 families were identified; among them, 107 were differentially expressed during diapause entry and termination. We focused on the roles of two of these miRNAs, miR-100 and miR-34, in regulating cell cycle progression; during the various stages of diapause entry, these miRNAs displayed opposing patterns of expression. A functional analysis revealed that miR-100 and miR-34 regulate the cell cycle during diapause entry by targeting polo-like kinase 1 (PLK1), leading to activation of the mitogen-activated protein kinase kinase-extracellular signal-regulated kinase-ribosomal S6 kinase 2 (MEK-ERK-RSK2) pathway and cyclin K, leading to suppression of RNA polymerase II (RNAP II) activity respectively. The findings presented in the present study provide insights into the functions of miR-100 and miR-34 and suggest that the expression profiles of miRNAs in Artemia can be used to characterize their functions in cell cycle regulation.

  2. Effects of genotoxicity and its consequences at the population level in sexual and asexual Artemia assessed by analysis of inter-simple sequence repeats (ISSR).

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-09-18

    There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects of the mutagen ethylmethane sulfonate (EMS) on a sexual (Artemia franciscana) and an asexual (Artemia parthenogenetica) species of brine shrimp. The method provides information similar to that obtained with assessment of RAPD (random amplification of polymorphic DNA) but is more robust. Genetic damage was transmitted to the F1 generation in both Artemia species, but the sexual species showed a greater degree of recovery, as shown by higher values of genomic template stability. There was a strong correlation between DNA damage and effects on individual fitness parameters: size, survival, reproduction and population growth. These effects persisted into the F2 generation in A. parthenogenetica, but in the sexual A. franciscana only effects on fecundity continued beyond the exposed generation, even though there were substantial alterations in ISSR patterns in the F1 generation. Genetic biomarkers can thus be indicative of effects at the population level, but sexually reproducing species have a considerable assimilative capacity for the effects of genotoxins.

  3. Probing the protective mechanism of poly-ß-hydroxybutyrate against vibriosis by using gnotobiotic Artemia franciscana and Vibrio campbellii as host-pathogen model.

    PubMed

    Baruah, Kartik; Huy, Tran T; Norouzitallab, Parisa; Niu, Yufeng; Gupta, Sanjay K; De Schryver, Peter; Bossier, Peter

    2015-03-30

    The compound poly-ß-hydroxybutyrate (PHB), a polymer of the short chain fatty acid ß-hydroxybutyrate, was shown to protect experimental animals against a variety of bacterial diseases, (including vibriosis in farmed aquatic animals), albeit through undefined mechanisms. Here we aimed at unraveling the underlying mechanism behind the protective effect of PHB against bacterial disease using gnotobiotically-cultured brine shrimp Artemia franciscana and pathogenic Vibrio campbellii as host-pathogen model. The gnotobiotic model system is crucial for such studies because it eliminates any possible microbial interference (naturally present in any type of aquatic environment) in these mechanistic studies and furthermore facilitates the interpretation of the results in terms of a cause effect relationship. We showed clear evidences indicating that PHB conferred protection to Artemia host against V. campbellii by a mechanism of inducing heat shock protein (Hsp) 70. Additionally, our results also showed that this salutary effect of PHB was associated with the generation of protective innate immune responses, especially the prophenoloxidase and transglutaminase immune systems - phenomena possibly mediated by PHB-induced Hsp70. From overall results, we conclude that PHB induces Hsp70 and this induced Hsp70 might contribute in part to the protection of Artemia against pathogenic V. campbellii.

  4. The suppressor of AAC2 Lethality SAL1 modulates sensitivity of heterologously expressed artemia ADP/ATP carrier to bongkrekate in yeast.

    PubMed

    Wysocka-Kapcinska, Monika; Torocsik, Beata; Turiak, Lilla; Tsaprailis, George; David, Cynthia L; Hunt, Andrea M; Vekey, Karoly; Adam-Vizi, Vera; Kucharczyk, Roza; Chinopoulos, Christos

    2013-01-01

    The ADP/ATP carrier protein (AAC) expressed in Artemia franciscana is refractory to bongkrekate. We generated two strains of Saccharomyces cerevisiae where AAC1 and AAC3 were inactivated and the AAC2 isoform was replaced with Artemia AAC containing a hemagglutinin tag (ArAAC-HA). In one of the strains the suppressor of ΔAAC2 lethality, SAL1, was also inactivated but a plasmid coding for yeast AAC2 was included, because the ArAACΔsal1Δ strain was lethal. In both strains ArAAC-HA was expressed and correctly localized to the mitochondria. Peptide sequencing of ArAAC expressed in Artemia and that expressed in the modified yeasts revealed identical amino acid sequences. The isolated mitochondria from both modified strains developed 85% of the membrane potential attained by mitochondria of control strains, and addition of ADP yielded bongkrekate-sensitive depolarizations implying acquired sensitivity of ArAAC-mediated adenine nucleotide exchange to this poison, independent from SAL1. However, growth of ArAAC-expressing yeasts in glycerol-containing media was arrested by bongkrekate only in the presence of SAL1. We conclude that the mitochondrial environment of yeasts relying on respiratory growth conferred sensitivity of ArAAC to bongkrekate in a SAL1-dependent manner.

  5. Probing the protective mechanism of poly-ß-hydroxybutyrate against vibriosis by using gnotobiotic Artemia franciscana and Vibrio campbellii as host-pathogen model

    PubMed Central

    Baruah, Kartik; Huy, Tran T.; Norouzitallab, Parisa; Niu, Yufeng; Gupta, Sanjay K.; De Schryver, Peter; Bossier, Peter

    2015-01-01

    The compound poly-ß-hydroxybutyrate (PHB), a polymer of the short chain fatty acid ß-hydroxybutyrate, was shown to protect experimental animals against a variety of bacterial diseases, (including vibriosis in farmed aquatic animals), albeit through undefined mechanisms. Here we aimed at unraveling the underlying mechanism behind the protective effect of PHB against bacterial disease using gnotobiotically-cultured brine shrimp Artemia franciscana and pathogenic Vibrio campbellii as host-pathogen model. The gnotobiotic model system is crucial for such studies because it eliminates any possible microbial interference (naturally present in any type of aquatic environment) in these mechanistic studies and furthermore facilitates the interpretation of the results in terms of a cause effect relationship. We showed clear evidences indicating that PHB conferred protection to Artemia host against V. campbellii by a mechanism of inducing heat shock protein (Hsp) 70. Additionally, our results also showed that this salutary effect of PHB was associated with the generation of protective innate immune responses, especially the prophenoloxidase and transglutaminase immune systems – phenomena possibly mediated by PHB-induced Hsp70. From overall results, we conclude that PHB induces Hsp70 and this induced Hsp70 might contribute in part to the protection of Artemia against pathogenic V. campbellii. PMID:25822312

  6. Comparison of Artemia-bacteria associations in brines, laboratory cultures and the gut environment: a study based on Chilean hypersaline environments.

    PubMed

    Quiroz, Mauricio; Triadó-Margarit, Xavier; Casamayor, Emilio O; Gajardo, Gonzalo

    2015-01-01

    The brine shrimp Artemia (Crustacea) and a diversity of halophilic microorganisms coexist in natural brines, salterns and laboratory cultures; part of such environmental microbial diversity is represented in the gut of Artemia individuals. Bacterial diversity in these environments was assessed by 16S rRNA gene denaturing gradient gel electrophoresis (DGGE) fingerprinting. Eight natural locations in Chile, where A. franciscana or A. persimilis occur, were sampled for analysis of free-living and gut-associated bacteria in water from nature and laboratory cultures. The highest ecological diversity (Shannon's index, H') was found in brines, it decreased in the gut of wild and laboratory animals, and in laboratory water. Significant differences in H' existed between brines and laboratory water, and between brines and gut of wild animals. The greatest similarity of bacterial community composition was between brines and the gut of field animals, suggesting a transient state of the gut microbiota. Sequences retrieved from DGGE patterns (n = 83) exhibited an average of 97.8% identity with 41 bacterial genera from the phyla Proteobacteria (55.4% of sequences match), Bacteroidetes (22.9%), Actinobacteria (16.9%) and Firmicutes (4.8%). Environment-exclusive genera distribution was seen in Sphingomonas and Paenibacillus (gut of field animals), Amaricoccus and Ornithinimicrobium (gut of laboratory animals), and Hydrogenophaga (water of laboratory cultures). The reported ecological and physiological capabilities of such bacteria can help to understand Artemia adaptation to natural and laboratory conditions.

  7. Active downward propulsion by oyster larvae in turbulence.

    PubMed

    Fuchs, Heidi L; Hunter, Elias J; Schmitt, Erika L; Guazzo, Regina A

    2013-04-15

    Oyster larvae (Crassostrea virginica) could enhance their settlement success by moving toward the seafloor in the strong turbulence associated with coastal habitats. We characterized the behavior of individual oyster larvae in grid-generated turbulence by measuring larval velocities and flow velocities simultaneously using infrared particle image velocimetry. We estimated larval behavioral velocities and propulsive forces as functions of the kinetic energy dissipation rate ε, strain rate γ, vorticity ξ and acceleration α. In calm water most larvae had near-zero vertical velocities despite propelling themselves upward (swimming). In stronger turbulence all larvae used more propulsive force, but relative to the larval axis, larvae propelled themselves downward (diving) instead of upward more frequently and more forcefully. Vertical velocity magnitudes of both swimmers and divers increased with turbulence, but the swimming velocity leveled off as larvae were rotated away from their stable, velum-up orientation in strong turbulence. Diving speeds rose steadily with turbulence intensity to several times the terminal fall velocity in still water. Rapid dives may require a switch from ciliary swimming to another propulsive mode such as flapping the velum, which would become energetically efficient at the intermediate Reynolds numbers attained by larvae in strong turbulence. We expected larvae to respond to spatial or temporal velocity gradients, but although the diving frequency changed abruptly at a threshold acceleration, the variation in propulsive force and behavioral velocity was best explained by the dissipation rate. Downward propulsion could enhance oyster larval settlement by raising the probability of larval contact with oyster reef patches.

  8. Complete Genome Sequences of Five Paenibacillus larvae Bacteriophages.

    PubMed

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

    2013-11-14

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

  9. Selenium impacts on razorback sucker, Colorado: Colorado River: III. Larvae

    USGS Publications Warehouse

    Hamilton, S.J.; Holley, K.M.; Buhl, K.J.; Bullard, F.A.

    2005-01-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged <1.6 ??g/L from 24-Road, 0.9 ??g/L from Horsethief, 5.5 ??g/L from Adobe Creek, and 10.7 ??g/L from the North Pond. Selenium in dietary items averaged 2.7 ??g/g in brine shrimp, 5.6 ??g/g in zooplankton from Horsethief east wetland, 20 ??g/g in zooplankton from Adobe Creek, and 39 ??g/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of ???4.6 ??g/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish.

  10. Prey capture of pike Esox lucius larvae in turbid water.

    PubMed

    Salonen, M; Engström-Ost, J

    2010-06-01

    Pike Esox lucius larvae captured fewer calanoid and cyclopoid copepods in turbid than in clear water, whereas no differences were detected in feeding rates on Daphnia longispina. Decreased capture of copepods may lead to lower growth and survival of E. lucius larvae in turbid areas, in particular, if cladocerans are scarce.

  11. The effects of dissolved gas supersaturation on white sturgeon larvae

    USGS Publications Warehouse

    Counihan, T.D.; Miller, A.I.; Mesa, M.G.; Parsley, M.J.

    2000-01-01

    Spill at dams has caused supersaturation of atmospheric gas in waters of the Columbia and Snake rivers and raised concerns about the effects of dissolved gas supersaturation (DGS) on white sturgeons Acipenser transmontanus. The timing and location of white sturgeon spawning and the dispersal of white sturgeon larvae from incubation areas makes the larval stage potentially vulnerable to the effects of DGS. To assess the effects of DGS on white sturgeon larvae, we exposed larvae to mean total dissolved gas (TDG) levels of 118% and 131% saturation in laboratory bioassay tests. Gas bubble trauma (GBT) was manifested as a gas bubble in the buccal cavity, nares, or both and it first occurred at developmental stages characterized by the formation of the mouth and gills. Exposure times of 15 min were sufficient to elicit these signs in larvae in various stages of development. No mortality was observed in larvae exposed to 118% TDG for 10 d, but 50% mortality occurred after a 13-d exposure to 131% TDG. The signs of GBT we observed resulted in positive buoyancy and alterations in behavior that may affect the dispersal and predation vulnerability of white sturgeon larvae. The exact depth distribution of dispersing white sturgeon larvae in the Columbia River currently is unknown. Thus, our results may represent a worst-case scenario if white sturgeon larvae are dispersed at depths with insufficient hydrostatic pressure to compensate for high TDG levels.

  12. Rapid bioassay to screen potential biopesticides in Tenebrio molitor larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simplified assay was devised to evaluate the response of Tenebrio molitor larvae to potential insect control products. The assay incorporates punched disks of flattened whole-grain bread placed in 96-well plates, with treatments applied topically, and neonate larvae added to each well. To evalua...

  13. Selenium impacts on razorback sucker, Colorado: Colorado River III. Larvae.

    PubMed

    Hamilton, Steven J; Holley, Kathy M; Buhl, Kevin J; Bullard, Fern A

    2005-06-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged <1.6 microg/L from 24-Road, 0.9 microg/L from Horsethief, 5.5 microg/L from Adobe Creek, and 10.7 microg/L from the North Pond. Selenium in dietary items averaged 2.7 microg/g in brine shrimp, 5.6 microg/g in zooplankton from Horsethief east wetland, 20 microg/g in zooplankton from Adobe Creek, and 39 microg/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of 4.6 microg/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish.

  14. Trail marking by larvae of the eastern tent caterpillar.

    PubMed

    Fitzgerald, T D

    1976-11-26

    Eastern tent caterpillars that are successful foragers deposit trails as they return to the tent that are more attractive than the exploratory trails of the unfed larvae. The trails of these fed returning larvae attract unfed tentmates to food finds anre chemical factors account for the attractiveness of these trails.

  15. Early detection of non-native fishes using fish larvae

    EPA Science Inventory

    Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection. First,...

  16. Loeffler's Syndrome Following Cutaneous Larva Migrans: An Uncommon Sequel

    PubMed Central

    Podder, Indrashis; Chandra, Somodyuti; Gharami, Ramesh Chandra

    2016-01-01

    Cutaneous larva migrans (CLM) is characterized by the formation of distinctive, tortuous, and serpentine skin lesions occurring as a result of epidermal burrowing by certain helminthic larvae. Although this condition is usually uneventful, rarely it may result in patchy pulmonary infiltration with peripheral eosinophilia, also called Loeffler's syndrome. This association is fairly uncommon and is thus being reported. PMID:27057020

  17. Discovery of mammalian hosts to Gnathostoma nipponicum larvae and prevalence of the larvae in rodents and insectivores.

    PubMed

    Oyamada, T; Kobayashi, H; Kindou, T; Kudo, N; Yoshikawa, H; Yoshikawa, T

    1996-09-01

    From September 1993 to November 1995, to clarify the natural infection of Gnathostoma nipponicum (G.n.) larvae in small wild mammals, a total of 313 animals consisted of three species of rodents and two species of insectivores, collected from an endemic area of this nematode in Aomori Prefecture, were investigated. Two species, Rattus norvegicus (R.n.) and Chimarrogale himalayica (C.h.) were infected with G.n. larvae, and the infection rate was extremely high with 27.2% and 72.7% in the former and latter. The infected animals harbored the larvae of 2-10 (mean: 6.0) in R.N. and 2-40 (10.6) in C.h., and a total of 273 larvae was recovered. The all larvae (18) from R.n. and the vast majority of the larvae (216/255: 82.4%) from C.h. were recovered from the musculature, and many encapsulated larvae were found in these portions of C.h. Taxonomically, all the larvae were identified as the advance third-stage larvae (AdL3) of G.n. The body length was 1,056-2,110 microns, and was larger than those of the naturally-infected AdL3 reported from cold-blooded animals. No morphological alterations or death of the larva was observed. From these results, it would seem that R.n. and C.h. are highly susceptible to G.n. larvae, and has very suitable characteristics as the hosts. Furthermore, a hypothesis is advanced that these mammals serves as the plausible paratenic hosts in the life cycle of G.n. This report is the first record of R.n. (Rodentia) and C.h. (Insectivora) naturally-infected with AdL3 of G.n.

  18. Geology of the Delta, Escalante, Price, Richfield and Salina 1 deg x 2 deg NTMS quadrangles, Utah

    NASA Astrophysics Data System (ADS)

    Thayer, P. A.

    1981-11-01

    The National Uranium Resource Evaluation (NURE) program was established to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The Grand Junction Office of the Department of Energy is responsible for administering the program. The Savannah River Laboratory (SRL) is responsible for hydrogeochemical and stream-sediment reconnaissance (HSSR) of 3.9 million sq km (1,500,000 mi(2)) in 37 eastern and western states. This document provides geologic and mineral resources reports for the Delta, Escalante, Price, Richfield, and Salina 1 deg x 2 deg National Topographic Map Series quadrangles, Utah. The purpose of these reports is to provide background geologic and mineral resources information to aid in the interpretation of NURE geochemical reconnaissance data. Except for the Escalante Quadrangle, each report is accompanied by a geologic map and a mineral locality map (Plates 1-8, in pocket).

  19. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds

    PubMed Central

    Geng, Haifeng; Tran-Gyamfi, Mary B.; Lane, Todd W.; Sale, Kenneth L.; Yu, Eizadora T.

    2016-01-01

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. We subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-term treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are “keystone” OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Taken together, these results provide valuable insights into the structure of the microbiota

  20. On-line stable isotope gas exchange reveals an inducible but leaky carbon concentrating mechanism in Nannochloropsis salina.

    PubMed

    Hanson, David T; Collins, Aaron M; Jones, Howland D T; Roesgen, John; Lopez-Nieves, Samuel; Timlin, Jerilyn A

    2014-09-01

    Carbon concentrating mechanisms (CCMs) are common among microalgae, but their regulation and even existence in some of the most promising biofuel production strains is poorly understood. This is partly because screening for new strains does not commonly include assessment of CCM function or regulation despite its fundamental role in primary carbon metabolism. In addition, the inducible nature of many microalgal CCMs means that environmental conditions should be considered when assessing CCM function and its potential impact on biofuels. In this study, we address the effect of environmental conditions by combining novel, high frequency, on-line (13)CO2 gas exchange screen with microscope-based lipid characterization to assess CCM function in Nannochloropsis salina and its interaction with lipid production. Regulation of CCM function was explored by changing the concentration of CO2 provided to continuous cultures in airlift bioreactors where cell density was kept constant across conditions by controlling the rate of media supply. Our isotopic gas exchange results were consistent with N. salina having an inducible "pump-leak" style CCM similar to that of Nannochloropsis gaditana. Though cells grew faster at high CO2 and had higher rates of net CO2 uptake, we did not observe significant differences in lipid content between conditions. Since the rate of CO2 supply was much higher for the high CO2 conditions, we calculated that growing cells bubbled with low CO2 is about 40 % more efficient for carbon capture than bubbling with high CO2. We attribute this higher efficiency to the activity of a CCM under low CO2 conditions.

  1. The influence of photoperiod and light intensity on the growth and photosynthesis of Dunaliella salina (chlorophyta) CCAP 19/30.

    PubMed

    Xu, Yanan; Ibrahim, Iskander M; Harvey, Patricia J

    2016-09-01

    The green microalga Dunaliella salina survives in a wide range of salinities via mechanisms involving glycerol synthesis and degradation and is exploited for large amounts of nutraceutical carotenoids produced under stressed conditions. In this study, D. salina CCAP 19/30 was cultured in varying photoperiods and light intensities to study the relationship of light with different growth measurement parameters, with cellular contents of glycerol, starch and carotenoids, and with photosynthesis and respiration. Results show CCAP 19/30 regulated cell volume when growing under light/dark cycles: cell volume increased in the light and decreased in the dark, and these changes corresponded to changes in cellular glycerol content. The decrease in cell volume in the dark was independent of cell division and biological clock and was regulated by the photoperiod of the light/dark cycle. When the light intensity was increased to above 1000 μmol photons m(-2) s(-1), cells displayed evidence of photodamage. However, these cells also maintained the maximum level of photosynthesis efficiency and respiration possible, and the growth rate increased as light intensity increased. Significantly, the intracellular glycerol content also increased, >2-fold compared to the content in light intensity of 500 μmol photons m(-2) s(-1), but there was no commensurate increase in the pool size of carotenoids. These data suggest that in CCAP 19/30 glycerol stabilized the photosynthetic apparatus for maximum performance in high light intensities, a role normally attributed to carotenoids.

  2. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds

    SciTech Connect

    Geng, Haifeng; Tran-Gyamfi, Mary B.; Lane, Todd W.; Sale, Kenneth L.; Yu, Eizadora T.

    2016-07-26

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. Here we subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-term treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are “keystone” OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Lastly, taken together, these results provide valuable insights into the structure of the

  3. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds

    DOE PAGES

    Geng, Haifeng; Tran-Gyamfi, Mary B.; Lane, Todd W.; ...

    2016-07-26

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. Here we subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-termmore » treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are “keystone” OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Lastly, taken together, these results provide valuable insights into the structure

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

    PubMed

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

    2015-09-01

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

  5. Mechanical recovery of inhibited cyathostomin larvae from equine intestinal tissue.

    PubMed

    Glover, I D; Henry, G M; Townsend, N B; Coles, G C

    2009-08-01

    The Stomacher is very widely used in food and medical research for extracting tissues. To determine whether nematode larvae were disrupted by the Stomacher, L3 larvae of Haemonchus contortus were homogenised for up to 40 min at full power but no larval disruption occurred. Therefore, tissue from the mucosa and submucosa of the caecum of horses collected from a licenced abattoir was treated to determine whether inhibited cyathostomin larvae could be extracted. The optimum time on full power for a 10-g sample was 20 min, and in three out of five caecal samples from different horses, significantly more larvae were recovered than with 6 h pepsin HCl digestion. It is concluded that the Stomacher provides a simple fast method of extracting inhibited nematode larvae from gastrointestinal tissues in the horse that could replace digestion with pepsin HCl.

  6. Habitat selection by marine larvae in changing chemical environments.

    PubMed

    Lecchini, D; Dixson, D L; Lecellier, G; Roux, N; Frédérich, B; Besson, M; Tanaka, Y; Banaigs, B; Nakamura, Y

    2017-01-15

    The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.

  7. Chemical spying in coral reef fish larvae at recruitment.

    PubMed

    Roux, Natacha; Brooker, Rohan M; Lecellier, Gaël; Berthe, Cécile; Frédérich, Bruno; Banaigs, Bernard; Lecchini, David

    2015-10-01

    When fish larvae recruit back to a reef, chemical cues are often used to find suitable habitat or to find juvenile or adult conspecifics. We tested if the chemical information used by larvae was intentionally produced by juvenile and adult conspecifics already on the reef (communication process) or whether the cues used result from normal biochemical processes with no active involvement by conspecifics ("spying" behavior by larvae). Conspecific chemical cues attracted the majority of larvae (four out of the seven species tested); although while some species were equally attracted to cues from adults and juveniles (Chromis viridis, Apogon novemfasciatus), two exhibited greater sensitivity to adult cues (Pomacentrus pavo, Dascyllus aruanus). Our results indicate also that spying cues are those most commonly used by settling fishes (C. viridis, P. pavo, A. novemfasciatus). Only one species (D. aruanus) preferred the odour of conspecifics that had had visual contact with larvae (communication).

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

    PubMed Central

    Graffi, Shmuel; Peretz, Avi; Wilamowski, Amos; Schnur, Heather; Akad, Fouad; Naftali, Modi

    2013-01-01

    Purpose. External ophthalmomyiasis (EO) is caused by infesting larvae belonging to various species of flies. Most documented cases result from sheep (Oestrus ovis) and Russian (Rhinoestrus purpureus) botfly larvae, but we recently discovered a rare case of EO caused by flesh fly (Sarcophaga argyrostoma) larvae. Here, we report the case of a patient with EO who had been hospitalized and sedated for 1 week because of unrelated pneumonia. Methods. Case report. Results. A total of 32 larvae were removed from the adnexae of both eyes. Larvae identification was confirmed through DNA analysis. Treatment with topical tobramycin resulted in complete resolution of EO. Conclusion. EO can be caused by S. argyrostoma, and the elderly and debilitated may require extra ocular protection against flies during sedation. PMID:24455366

  9. Neuromechanics of crawling in D. melanogaster larvae

    NASA Astrophysics Data System (ADS)

    Pehlevan, Cengiz; Paoletti, Paolo; Mahadevan, L.

    2015-03-01

    Nervous system, body and environment interact in non-trivial ways to generate locomotion and thence behavior in an organism. Here we present a minimal integrative mathematical model to describe the simple behavior of forward crawling in Drosophila larvae. Our model couples the excitation-inhibition circuits in the nervous system to force production in the muscles and body movement in a frictional environment, which in turn leads to a proprioceptive signal that feeds back to the nervous system. Our results explain the basic observed phenomenology of crawling with or without proprioception, and elucidate the stabilizing role of proprioception in crawling with respect to external and internal perturbations. Our integrated approach allows us to make testable predictions on the effect of changing body-environment interactions on crawling, and serves as a substrate for the development of hierarchical models linking cellular processes to behavior.

  10. Antibacterial properties of grapefruit seed extract against Paenibacillus larvae subsp. larvae.

    PubMed

    Semprini, P; Langella, V; Pasini, B; Falda, M T; Calvarese, S

    2004-01-01

    Twenty-one samples of grapefruit seed extract (GSE) either from marketed products or provided by an apiculturist were analysed to verify their inhibition activity, in particular against Paenibacillus larvae subsp. larvae, responsible for American foulbrood. The bactericide capacity of GSE has been measured in Bacillus subtilis BGA, Bacillus cereus 11778, Bacillus cereus K250 and Micrococcus luteus 9341a; these bacteria are normally used in the laboratory to study inhibitors. The results showed that not all GSE have the same inhibitory activity and two of those analysed do not inhibit the five bacteria used. Considering that 19 samples inhibited American foulbrood bacillus, the authors conclude that the use of a natural product (such as GSE) to control this important disease of bees, can be used as a substitute for chemotherapeutic products, after appropriate expedients.

  11. Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae.

    PubMed

    Penglase, S; Harboe, T; Sæle, O; Helland, S; Nordgreen, A; Hamre, K

    2013-01-01

    Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg(-1) dry weight; MI group) or copepod (129 mg I kg(-1) DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg(-1) DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg(-1) DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg(-1) DW.

  12. Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae

    PubMed Central

    Penglase, S; Harboe, T; Sæle, Ø; Helland, S; Nordgreen, A

    2013-01-01

    Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg-1 dry weight; MI group) or copepod (129 mg I kg-1 DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg-1 DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg-1 DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg-1 DW. PMID:23638355

  13. How to Kill the Honey Bee Larva: Genomic Potential and Virulence Mechanisms of Paenibacillus larvae

    PubMed Central

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

    2014-01-01

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

  14. In vivo and in vitro antiplasmodial activities of some plants traditionally used in Guatemala against malaria.

    PubMed Central

    Franssen, F F; Smeijsters, L J; Berger, I; Medinilla Aldana, B E

    1997-01-01

    We present an evaluation of the antiplasmodial and cytotoxic effects of four plants commonly used in Guatemalan folk medicine against malaria. Methanol extracts of Simarouba glauca D. C., Sansevieria guineensis Willd, Croton guatemalensis Lotsy, and Neurolaena lobata (L.)R.Br. significantly reduced parasitemias in Plasmodium berghei-infected mice. Dichloromethane fractions were screened for their cytotoxicities on Artemia salina (brine shrimp) larvae, and 50% inhibitory concentrations were determined for Plasmodium falciparum in in vitro cultures. Both chloroquine-susceptible and -resistant strains of P. falciparum were significantly inhibited by these extracts. Of all dichloromethane extracts, only the S. glauca cortex extract was considered to be toxic to nauplii of A. salina in the brine shrimp test. PMID:9210673

  15. Effects of various diets on the calcium and phosphorus composition of mealworms (Tenebrio molitor larvae) and superworms (Zophobas morio larvae).

    PubMed

    Latney, La'Toya V; Toddes, Barbara D; Wyre, Nicole R; Brown, Dorothy C; Michel, Kathryn E; Briscoe, Johanna A

    2017-02-01

    OBJECTIVE To evaluate whether the nutritive quality of Tenebrio molitor larvae and Zophobas morio larvae, which are commonly cultured as live food sources, is influenced by 4 commercially available diets used as nutritional substrates; identify which diet best improved calcium content of larvae; and identify the feeding time interval that assured the highest calcium intake by larvae. ANIMALS 2,000 Zophobas morio larvae (ie, superworms) and 7,500 Tenebrio molitor larvae (ie, mealworms). PROCEDURES Larvae were placed in control and diet treatment groups for 2-, 7-, and 10-day intervals. Treatment diets were as follows: wheat millings, avian hand feeding formula, organic avian mash diet, and a high-calcium cricket feed. Control groups received water only. After treatment, larvae were flash-frozen live with liquid nitrogen in preparation for complete proximate and mineral analyses. Analyses for the 2-day treatment group were performed in triplicate. RESULTS The nutrient composition of the high-calcium cricket feed groups had significant changes in calcium content, phosphorus content, and metabolizable energy at the 2-day interval, compared with other treatment groups, for both mealworms and superworms. Calcium content and calcium-to-phosphorus ratios for larvae in the high-calcium cricket feed group were the highest among the diet treatments for all treatment intervals and for both larval species. CONCLUSIONS AND CLINICAL RELEVANCE A 2-day interval with the high-calcium cricket feed achieved a larval nutrient composition sufficient to meet National Research Council dietary calcium recommendations for nonlactating rats. Mealworm calcium composition reached 2,420 g/1,000 kcal at 48 hours, and superworm calcium composition reached 2,070g/1,000 kcal at 48 hours. These findings may enable pet owners, veterinarians, insect breeders, and zoo curators to optimize nutritive content of larvae fed to insectivorous animals.

  16. A distinct sequence in the adenine nucleotide translocase from Artemia franciscana embryos is associated with insensitivity to bongkrekate and atypical effects of adenine nucleotides on Ca2+ uptake and sequestration.

    PubMed

    Konràd, Csaba; Kiss, Gergely; Töröcsik, Beata; Lábár, János L; Gerencser, Akos A; Mándi, Miklós; Adam-Vizi, Vera; Chinopoulos, Christos

    2011-03-01

    Mitochondria isolated from embryos of the crustacean Artemia franciscana lack the Ca(2+)-induced permeability transition pore. Although the composition of the pore described in mammalian mitochondria is unknown, the impacts of several effectors of the adenine nucleotide translocase (ANT) on pore opening are firmly established. Notably, ADP, ATP and bongkrekate delay, whereas carboxyatractyloside hastens, Ca(2+)-induced pore opening. Here, we report that adenine nucleotides decreased, whereas carboxyatractyloside increased, Ca(2+) uptake capacity in mitochondria isolated from Artemia embryos. Bongkrekate had no effect on either Ca(2+) uptake or ADP-ATP exchange rate. Transmission electron microscopy imaging of Ca(2+)-loaded Artemia mitochondria showed needle-like formations of electron-dense material in the absence of adenine nucleotides, and dot-like formations in the presence of adenine nucleotides or Mg(2+). Energy-filtered transmission electron microscopy showed the material to be rich in calcium and phosphorus. Sequencing of the Artemia mRNA coding for ANT revealed that it transcribes a protein with a stretch of amino acids in the 198-225 region with 48-56% similarity to those from other species, including the deletion of three amino acids in positions 211, 212 and 219. Mitochondria isolated from the liver of Xenopus laevis, in which the ANT shows similarity to that in Artemia except for the 198-225 amino acid region, demonstrated a Ca(2+)-induced bongkrekate-sensitive permeability transition pore, allowing the suggestion that this region of ANT may contain the binding site for bongkrekate.

  17. Distribution of metals during digestion by cutthroat trout fed benthic invertebrates contaminated in the Clark Fork River, Montana and the Coeur d'Alene River, Idaho, U.S.A., and fed artificially contaminated Artemia

    USGS Publications Warehouse

    Farag, A.M.; Suedkamp, M.J.; Meyer, J.S.; Barrows, R.; Woodward, D.F.

    2000-01-01

    The concentrations of essential amino acids in three, undigested invertebrate diets collected from the Clark Fork River (CFR) for cutthroat trout were similar to each other, but were c. 25–75% less than Artemia that were exposed to a mixture of arsenic, copper, cadmium, lead and zinc in the laboratory. The Artemia diet appeared less palatable and the texture, quantity and appearance of the intestinal contents differed between fish fed the Artemia and CFR diets. The Pb% in the fluid fraction of the intestinal contents was greater for the Artemia (29%) than for the CFR diets (10–17%), and the Cu% in the amino acid plus metal fraction of the intestinal contents was greater for the Artemia (78%) than for two of the three CFR diets (67% and 70%). Intestinal contents of fish fed invertebrate diets collected from various sites on the Coeur d'Alene River (CDA), Idaho, were similar in texture, quantity, and appearance. For fish fed the CDA diets, differences in the distribution of metals among fractions of the digestive fluids appeared to be related to concentrations of metals in the invertebrate diets. Pb% was lowest of all metals in the fluid portion of the intestinal contents. However, >80% of all metals in the hind gut were associated with the particulate fraction where they may still be available for uptake through pinocytosis.

  18. [Effect of temperature on the viability of Trichinella spiralis larvae].

    PubMed

    Randazzo, Viviana R; La Sala, Luciano F; Costamagna, Sixto R

    2011-01-01

    The aim of this work was to study the effect of temperature on the viability of free and encysted larvae of Trichinella spiralis from southwest Buenos Aires province, Argentina. Larvae were treated at variable temperatures (-30 °C, -20 °C, 4 °C, 20 °C, gradual heating between 0-100 °C). The time necessary to kill 100 % of larvae was calculated. During the first days of freezing, larval mortality significantly increased as a function of time. Regardless of temperature, encysted larvae survived longer than the free ones. At -30 °C, -20 °C, and 20 °C there were no significant differences between the survival curves for each larval stage. At 4 °C, mortality was less severe for encysted larvae. All free and encysted larvae died at 61 days and 95 days (-30 °C), 160 days and 180 days (-20 °C), 280 days and 330 days (4 °C) and 460 days and 590 days (20 °C), respectively. Cooking at 90 °C and 100 °C during 15 minutes killed 100 % of free and encysted larvae, respectively. Our results suggest that temperatures and exposure times traditionally used to treat meat products with a potential to transmit T. spiralis are not entirely efficient.

  19. Effects of low temperatures on larvae of the genus Trichinella.

    PubMed

    Hulínská, D; Figallová, V; Shaikenov, B

    1985-01-01

    We examined the effect of an exposure to -25 degrees C (for 8 days) on the histochemistry and the fine structure of 30-day-old Trichinella larvae from muscle fibres of the diaphragm. The larvae of T. pseudospiralis and T. nelsoni were either destroyed in the muscle fibres, dead, eosinophile, or were not found. The structureless mass of a degenerating, changed sarcoplasm was highly AIP-active, and gave a weak positive reaction for SS-groups of proteins. The wall of the deformed capsule around T. nelsoni, and the cuticle of the larva, stained diffusely; it did not contain AM. In a few muscle fibres exposed to -25 degrees C, histochemical reactions of the capsule surrounding larvae of T. nativa and sometimes of larvae of T. spiralis, and reaction of the changed sarcoplasm, were similar to those of the controls. A few mobile larvae were isolated by digestion only from a diaphragm infected with T. nativa. Deterrent to a prolonged survival of larvae were the formation of ice crystals and a denaturation of proteins by which the sarcoplasm of the infected muscle fibre was changed gradually into both a plasmolytically and karyolytically altered mass. Degenerative changes in the fine structure of infected muscle fibres were demonstrated by the presence of "spheromembranous bodies" in the sarcoplasm resembling myeline formations observed after exposure to poisonous substances, e.g., colchicine.

  20. The phylogenetic significance of colour patterns in marine teleost larvae

    PubMed Central

    Baldwin, Carole C

    2013-01-01

    Ichthyologists, natural-history artists, and tropical-fish aquarists have described, illustrated, or photographed colour patterns in adult marine fishes for centuries, but colour patterns in marine fish larvae have largely been neglected. Yet the pelagic larval stages of many marine fishes exhibit subtle to striking, ephemeral patterns of chromatophores that warrant investigation into their potential taxonomic and phylogenetic significance. Colour patterns in larvae of over 200 species of marine teleosts, primarily from the western Caribbean, were examined from digital colour photographs, and their potential utility in elucidating evolutionary relationships at various taxonomic levels was assessed. Larvae of relatively few basal marine teleosts exhibit erythrophores, xanthophores, or iridophores (i.e. nonmelanistic chromatophores), but one or more of those types of chromatophores are visible in larvae of many basal marine neoteleosts and nearly all marine percomorphs. Whether or not the presence of nonmelanistic chromatophores in pelagic marine larvae diagnoses any major teleost taxonomic group cannot be determined based on the preliminary survey conducted, but there is a trend toward increased colour from elopomorphs to percomorphs. Within percomorphs, patterns of nonmelanistic chromatophores may help resolve or contribute evidence to existing hypotheses of relationships at multiple levels of classification. Mugilid and some beloniform larvae share a unique ontogenetic transformation of colour pattern that lends support to the hypothesis of a close relationship between them. Larvae of some tetraodontiforms and lophiiforms are strikingly similar in having the trunk enclosed in an inflated sac covered with xanthophores, a character that may help resolve the relationships of these enigmatic taxa. Colour patterns in percomorph larvae also appear to diagnose certain groups at the interfamilial, familial, intergeneric, and generic levels. Slight differences in generic

  1. Comparative genomics of 9 novel Paenibacillus larvae bacteriophages

    PubMed Central

    Stamereilers, Casey; LeBlanc, Lucy; Yost, Diane; Amy, Penny S.; Tsourkas, Philippos K.

    2016-01-01

    ABSTRACT American Foulbrood Disease, caused by the bacterium Paenibacillus larvae, is one of the most destructive diseases of the honeybee, Apis mellifera. Our group recently published the sequences of 9 new phages with the ability to infect and lyse P. larvae. Here, we characterize the genomes of these P. larvae phages, compare them to each other and to other sequenced P. larvae phages, and putatively identify protein function. The phage genomes are 38–45 kb in size and contain 68–86 genes, most of which appear to be unique to P. larvae phages. We classify P. larvae phages into 2 main clusters and one singleton based on nucleotide sequence identity. Three of the new phages show sequence similarity to other sequenced P. larvae phages, while the remaining 6 do not. We identified functions for roughly half of the P. larvae phage proteins, including structural, assembly, host lysis, DNA replication/metabolism, regulatory, and host-related functions. Structural and assembly proteins are highly conserved among our phages and are located at the start of the genome. DNA replication/metabolism, regulatory, and host-related proteins are located in the middle and end of the genome, and are not conserved, with many of these genes found in some of our phages but not others. All nine phages code for a conserved N-acetylmuramoyl-L-alanine amidase. Comparative analysis showed the phages use the “cohesive ends with 3′ overhang” DNA packaging strategy. This work is the first in-depth study of P. larvae phage genomics, and serves as a marker for future work in this area. PMID:27738559

  2. Anguilliform larvae collected off North Carolina

    USGS Publications Warehouse

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

    2007-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2006-01-01

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

  4. Effects of UV/Ag-TiO2/O3 advanced oxidation on unicellular green alga Dunaliella salina: implications for removal of invasive species from ballast water.

    PubMed

    Wu, Donghai; You, Hong; Du, Jiaxuan; Chen, Chuan; Jin, Darui

    2011-01-01

    The UV/Ag-TiO2/O3 process was investigated for ballast water treatment using Dunaliella salina as an indicator. Inactivation curves were obtained, and the toxicity of effluent was determined. Compared with individual unit processes using ozone or UV/Ag-TiO2, the inactivation efficiency of D. salina by the combined UV/Ag-TiO2/O3 process was enhanced. The presence of ozone caused an immediate decrease in chlorophyll a (chl-a) concentration. Inactivation efficiency and ch1-a removal efficiency were positively correlated with ozone dose and ultraviolet intensity. The initial total residual oxidant (TRO) concentration of effluent increased with increasing ozone dose, and persistence of TRO resulted in an extended period of toxicity. The results suggest that UV/Ag-TiO2/O3 has potential for ballast water treatment.

  5. Reducing Vibrio load in Artemia nauplii using antimicrobial photodynamic therapy: a promising strategy to reduce antibiotic application in shrimp larviculture.

    PubMed

    Asok, Aparna; Arshad, Esha; Jasmin, C; Pai, S Somnath; Singh, I S Bright; Mohandas, A; Anas, Abdulaziz

    2012-01-01

    We propose antimicrobial photodynamic therapy (aPDT) as an alternative strategy to reduce the use of antibiotics in shrimp larviculture systems. The growth of a multiple antibiotic resistant Vibrio harveyi strain was effectively controlled by treating the cells with Rose Bengal and photosensitizing for 30 min using a halogen lamp. This resulted in the death of >50% of the cells within the first 10 min of exposure and the 50% reduction in the cell wall integrity after 30 min could be attributed to the destruction of outer membrane protein of V. harveyi by reactive oxygen intermediates produced during the photosensitization. Further, mesocosm experiments with V. harveyi and Artemia nauplii demonstrated that in 30 min, the aPDT could kill 78.9% and 91.2% of heterotrophic bacterial and Vibrio population respectively. In conclusion, the study demonstrated that aPDT with its rapid action and as yet unreported resistance development possibilities could be a propitious strategy to reduce the use of antibiotics in shrimp larviculture systems and thereby, avoid their hazardous effects on human health and the ecosystem at large.

  6. Probing the phenomenon of trained immunity in invertebrates during a transgenerational study, using brine shrimp Artemia as a model system

    PubMed Central

    Norouzitallab, Parisa; Baruah, Kartik; Biswas, Priyanka; Vanrompay, Daisy; Bossier, Peter

    2016-01-01

    The invertebrate’s innate immune system was reported to show some form of adaptive features, termed trained immunity. However, the memory characteristics of innate immune system and the mechanisms behind such phenomena remain unclear. Using the invertebrate model Artemia, we verified the possibility or impossibility of trained immunity, examining the presence or absence of enduring memory against homologous and heterologous antigens (Vibrio spp.) during a transgenerational study. We also determined the mechanisms behind such phenomenon. Our results showed the occurrence of memory and partial discrimination in Artemia’s immune system, as manifested by increased resistance, for three successive generations, of the progenies of Vibrio-exposed ancestors towards a homologous bacterial strain, rather than to a heterologous strain. This increased resistance phenotype was associated with elevated levels of hsp70 and hmgb1 signaling molecules and alteration in the expression of key innate immunity-related genes. Our results also showed stochastic pattern in the acetylation and methylation levels of H4 and H3K4me3 histones, respectively, in the progenies whose ancestors were challenged. Overall results suggest that innate immune responses in invertebrates have the capacity to be trained, and epigenetic reprogramming of (selected) innate immune effectors is likely to have central place in the mechanisms leading to trained immunity. PMID:26876951

  7. Estimate of the effects of ultraviolet radiation on the mortality of Artemia franciscana in naupliar and adult stages

    NASA Astrophysics Data System (ADS)

    Dattilo, Arduino M.; Bracchini, Luca; Carlini, Laura; Loiselle, Steven; Rossi, Claudio

    2005-07-01

    The impact of different doses of artificial ultraviolet (UV) radiation on the growth stages of a marine zooplankton was investigated using laboratory microcosms. Mortality percentages of naupliar and adult samples of Artemia franciscana were recorded in relation to different UV doses (single exposure: 75, 150, 300, 600, 1,200, 2,400, 3,900, 7,800 J m-2) at specific observation times after exposure (24, 48, 72, 96 and 120 h). The relationship between mortality percentage and UV dose showed significant differences in relation to the zooplankton growth stage. The elevated susceptibility of the naupliar samples to UV radiation is described through a mortality model based on a logistic equation. The data analysis shows that the slope of mortality versus dose remains the same for the two growth stages while the lethal dose in the naupliar stage was 3.3 smaller than that determined for the adult stage. The slope of the UV mortality rate versus post-incubation time was found to be significantly different (P<0.05) at low UV doses for the two life stages examined, i.e. naupliar and adult. The lower value of LD50 in naupliar stages compared to that for adults confirms that in the early growth stage this marine zooplankton is more susceptible to UV radiation.

  8. Does a Change from Whole to Powdered Food (Artemia franciscana eggs) Increase Oviposition in the Ladybird Coleomegilla maculata?

    PubMed Central

    Riddick, Eric W.; Wu, Zhixin

    2015-01-01

    The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered vs. whole Artemia franciscana (A. franciscana) (brine shrimp) eggs with or without a dietary supplement on development and reproduction of Coleomegilla maculata (C. maculata) (Coleoptera: Coccinellidae). We tested the hypotheses that (1) powdered A. franciscana eggs are more suitable than whole eggs; and (2) palmitic acid, a common fatty acid in natural prey, i.e., aphids, is an effective dietary supplement. Development time, pre-imaginal survival, sex ratio, and body weight of adults did not differ significantly amongst individuals fed powdered vs. whole eggs, with or without 5% palmitic acid. Significantly more oviposition occurred when females were fed powdered eggs than whole eggs and powdered eggs with 5% palmitic acid than whole eggs with or without 5% palmitic acid. A weak functional relationship was found between pre-oviposition time and total oviposition by females fed powdered eggs with 5% palmitic acid; pre-oviposition time decreased as oviposition increased. Food treatments had no significant differential effect on progeny (egg) hatch rate. In conclusion, a simple change in A. franciscana egg texture and particle size (i.e., blending whole eggs into a dust-like powder) increases oviposition in C. maculata. Supplementing powdered eggs with 5% palmitic acid might accelerate oogenesis (egg maturation) in some females. PMID:26466902

  9. APC/CCDC20 and APC/C play pivotal roles in the process of embryonic development in Artemia sinica

    PubMed Central

    Zhang, Mengchen; Yao, Feng; Luan, Hong; Zhao, Wei; Jing, Ting; Zhang, Shuang; Hou, Lin; Zou, Xiangyang

    2016-01-01

    Anaphase Promoting Complex or Cyclosome (APC/C) is a representative E3 ubiquitin ligase, triggering the transition of metaphase to anaphase by regulating degradation and ensures the exit from mitosis. Cell division cycle 20 (CDC20) and Cell division cycle 20 related protein 1 (CDH1), as co-activators of APC/C, play significant roles in the spindle assembly checkpoint, guiding ubiquitin-mediated degradation, together with CDC23. During the embryonic development of the brine shrimp, Artemia sinica, CDC20, CDH1 and CDC23 participate in cell cycle regulation, but the specific mechanisms of their activities remain unknown. Herein, the full-length cDNAs of cdc20 and cdc23 from A. sinica were cloned. Real-time PCR analyzed the expression levels of As-cdc20 and As-cdc23. The locations of CDH1, CDC20 and CDC23 showed no tissue or organ specificity. Furthermore, western blotting showed that the levels of As-CDC20, securin, cyclin B, CDK1, CDH1, CDC14B, CDC23 and geminin proteins conformed to their complicated degradation relationships during different embryo stages. Our research revealed that As-CDC20, As-CDH1 and APC mediate the mitotic progression, downstream proteins degradation and cellular differentiation in the process of embryonic development in A. sinica. PMID:27991546

  10. Identification of a gene encoding the light-harvesting chlorophyll a/b proteins of photosystem I in green alga Dunaliella salina.

    PubMed

    Liang, Xue; Qiao, Dairong; Huang, Min; Yi, Xiuli; Bai, Linhan; Xu, Hui; Wei, Liang; Zeng, Jing; Cao, Yi

    2008-04-01

    There are four LhcII genes of Dunaliella salina have been submitted to the database of GenBank. However, little is known about Lhca genes of this green alga, although this knowledge might be available to study the composition and phylogenesis of Lhc gene family. Recently, one Lhca gene was been cloned from the green alga D. salina by PCR amplification using degenerate primers. This cDNA, designated as DsLhca1, contains an open reading frame encoded a protein of 222 amino acids with a calculated molecular mass of 27.8 kDa. DsLhca1 is predicted to contain three transmembrane domains and a N-terminal chloroplast transit peptide (cTP) with length of 33 amino acids. The genomic sequence of DsLhca1 is composed of five introns. The deduced polypeptide sequence of this gene showed a lower degree of identity (less than 30%) with LHCII proteins from D. salina. But its homology to Lhca proteins of other algae (Volvox carteri Lhca_AF110786) was higher with pairwise identities of up to 67.1%. Phylogenetic analysis indicated that DsLhcal protein cannot be assigned to any types of Lhca proteins in higher plants or in Chlamydomonas reinhardtii.

  11. U-Pb zircon geochronology of rocks in the Salinas Valley region of California: A reevaluation of the crustal structure and origin of the Salinian block

    USGS Publications Warehouse

    Barth, A.P.; Wooden, J.L.; Grove, M.; Jacobson, C.E.; Pedrick, J.N.

    2003-01-01

    The Salinian block in the Salinas Valley region of central California consists of arc granitic and metasedimentary rocks (schist of Sierra de Salinas) sandwiched between coeval high-pressure, low-temperature me??lange belts. U-Pb zircon ages of three granitic plutons from this region range from 88 to 82 Ma, and coexisting biotite yielded 40Ar/39Ar cooling ages of 76-75 Ma. The U-Pb ages from detrital zircons indicate derivation of the protolith of the schist from a 117-81 Ma igneous provenance. Muscovite and biotite 40Ar/ 39Ar cooling ages of 72-68 Ma from the nearby schist are distinctly younger than those from the granitic plutons. These data indicate that deposition and metamorphism of the schist occurred after emplacement of adjacent granitic rocks, contradicting the prevailing view that the schist comprises the local framework for the Salinian arc. We propose that the schist of Sierra de Salinas was thrust beneath the Salinian magmatic arc along a Campanian thrust fault that has not been recognized. This hypothesis implies that the Salinian arc originated as a klippe of basement rocks derived from the vicinity of the western Mojave Desert. Thrusting initiated southeastward-migrating Laramide tectonism of a style similar to that which formed the Vincent thrust and the latest Cretaceous and Paleocene Pelona and Orocopia Schists of southern California and southwestern Arizona.

  12. Molecular taxonomy of Dunaliella (Chlorophyceae), with a special focus on D. salina: ITS2 sequences revisited with an extensive geographical sampling

    PubMed Central

    2012-01-01

    We used an ITS2 primary and secondary structure and Compensatory Base Changes (CBCs) analyses on new French and Spanish Dunallela salina strains to investigate their phylogenetic position and taxonomic status within the genus Dunaliella. Our analyses show a great diversity within D. salina (with only some clades not statistically supported) and reveal considerable genetic diversity and structure within Dunaliella, although the CBC analysis did not bolster the existence of different biological groups within this taxon. The ITS2 sequences of the new Spanish and French D. salina strains were very similar except for two of them: ITC5105 "Janubio" from Spain and ITC5119 from France. Although the Spanish one had a unique ITS2 sequence profile and the phylogenetic tree indicates that this strain can represent a new species, this hypothesis was not confirmed by CBCs, and clarification of its taxonomic status requires further investigation with new data. Overall, the use of CBCs to define species boundaries within Dunaliella was not conclusive in some cases, and the ITS2 region does not contain a geographical signal overall. PMID:22520929

  13. Simple clearing technique as species determination tool in blowfly larvae.

    PubMed

    Niederegger, Senta; Wartenberg, Nelly; Spiess, Roland; Mall, Gita

    2011-03-20

    A simple clearing technique is presented by which species specific structures and organs of blowfly larvae can easily be visualized and displayed without any danger of mechanical damages or dislocations of delicate formations and without fixation of the object.

  14. [Community features of Sacrabaeoida larvae in Stipa grandis steppe].

    PubMed

    Xinmin, Liu; Ning, Wu

    2004-09-01

    The study showed that in the Stipa grandis steppe of Inner Mongolia, there were 4 families and 9 species of Scarabaeoidea larvae, among which, the numbers of species and individuals of Melolonthidae were more than those of other families. The important value of the dominant species in Scarabaeoidea larvae community were Trematodes tenebrioides > Serica orientalis > Amphimallon solstitialis > Cyriopertha arcuata. Based on the features of their seasonal dynamics, they could be classified into three kinds. The first kind was that their density peak occurred in spring and autumn, such as Serica orientalis. Cyriopertha arcuata belonged to the second kind, and its density had no obvious fluctuation through all the year. Trematodes tenebrioides and Amphimallon solstitialis could be classified into the third kind, and their density peak all occurred in autumn. The biodiversity index of Scarabaeoidea larvae community was relatively higher in autumn than in spring and summer. Although the richness of Scarabaeoidea larvae populations was not lower in spring, their composition was very simple.

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

    PubMed Central

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

    2011-01-01

    Objective To determine lead level primarily in Culex quinquefasciatus (Cx. quinquefasciatus), and Culex gelidus (Cx. gelidus) larvae inhabiting lead consuming factories, and to putatively estimate eco-toxicological impact of effluents from the firms. Methods Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry (AAS). Results Cx. quinquefasciatus was the most abundant species followed by Cx. gelidus. The levels of lead were higher in the Cx. quinquefasciatus (1.08-47.47 µg/g), than in the wastewaters surface (0.01-0.78 µg/mL) from the factories or closer areas around factories. Other species were not reaching the criteria for lead determination. Conclusions The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination, to complemente conventional techniques. PMID:23569727

  16. Using Fish Larvae to Connect Landscapes to Coastal Fisheries

    EPA Science Inventory

    We show preliminary results from research using chemical biomarkers in fish larvae to refine our conceptual and quantative models that describe the flow of energy and nutrients from the land to coastal aquatic food webs.

  17. Culturing Embryos and Larvae of Marine Molluscs and Protochordates.

    ERIC Educational Resources Information Center

    Healey, R.; Turner, S. C.

    1979-01-01

    Presents a description for maintaining adult forms of molluscs and protochordates in order to obtain gametes for laboratory studies of animal development. The methods also include those for culturing embryonic larvae forms in vitro. (Author/SA)

  18. Improved Software for Quantifying the Behavior of Drosophila Larvae

    NASA Astrophysics Data System (ADS)

    Bernat, Natalie; Gershow, Marc

    A key advantage of small crawling organisms like C elegans and the Drosophila larva is that their behaviors may be assayed automatically using computer vision software. Current state of the art software is capable of detecting the positions and postures of crawling larvae and automatically categorize their behaviors in parallel. However, these algorithms, which are based on frame-by-frame analysis of thresholded black and white images, fail to correctly describe the postures of larvae executing sharp bends and have difficulty separating multiple larvae that are physically touching. We present new tracking software that uses intensity information in grayscale images and applies temporal smoothness constraints to positions and postures. We implemented this software as an ImageJ plugin, extending its portability and applicability.

  19. Prolactin-like hormone in the nematode Trichinella spiralis larvae.

    PubMed

    Quintanar, J Luis; Salinas, Eva; Guerrero, Raquel; Gómez, Rigoberto; Vidal, Sergio; Aranda, Jorge; Clapp, Carmen

    2007-06-01

    Expression of prolactin (PRL) or prolactin-like hormone has been reported in invertebrates. We investigated the larval phase of Trichinella spiralis: (a) to express 23 kDa PRL, (b) to define its localization and (c) to test its possible biological activity. Immunostaining in isolated larvae demonstrated positive material to 23 kDa PRL by all along the stichosome, specifically in the stichocytes. Homogenized immunoblot larvae showed a 23 kDa protein band. To assess PRL release and its biological activity, larvae were incubated in culture medium and the excretory/secretory products were analyzed by the Nb2 cells bioassay. A cellular growth equivalent until 10 nM PRL and using antibody against 23 kDa PRL, the growth was blocked. In conclusion our result provides evidence that PRL-like hormone is expressed and secreted by the larvae of T. spiralis.

  20. Geodynamic evolution of the Salinas de Añana diapir in the Basque-Cantabrian Basin, Western Pyrenees

    NASA Astrophysics Data System (ADS)

    Frankovic, Allen; Eguiluz, Luis; Martínez-Torres, Luis M.

    2016-02-01

    The Salinas de Añana diapir is located in the Basque-Cantabrian basin part of the great evaporite basin, along with the Gulf of Mexico and the Central European basin, when the fragmentation of Pangea started. The evolution of these basins can only be achieved by understanding the control of salt in the sedimentary and tectonic evolution of these basins. Sedimentation began with clastic Buntsandstein sediments and minor Muschelkalk limestones. Subsequent Keuper evaporites are the bottom of sedimentary cover constituted by Jurassic limestones and marls, a clastic Lower Cretaceous and an alternant limestone and marl Upper Cretaceous, whose deposition has been conditioned by salt tectonics. The emplacement of salt extends from the Aptian until now, favored by the duplication of the salt thickness associated with the thrust of Sierra Cantabria, so it is an excellent example to study changes in the regime of intrusion along the time. The geodynamic evolution of the Salinas de Añana diapir was determined through the interpretation of 45 reprocessed seismic lines, along with information from three wells. Migration of the salt in this diapir, conditioned by N120E and N30E pre-Alpine basement lineations, was determined using time isopach maps of the various rock layers. Vertical evolution of the diapir was determined through the reconstruction of a north-south section at various geologic times by flattening the respective seismic horizons. A minimum of salt flow into the diapir coincides with a minimum rate of sedimentation during the Turonian. Similarly, maximum flows of salt into the diapir occurred during the Coniacian and Lower Santonian and again from the end of the Lower Miocene to the present, coinciding with maximum rates of sedimentation during these times. In the Tertiary, probably during the Oligocene, the diapir was displaced to the south by the Sierra Cantabria thrust, maintaining the contact between the evaporites of diapir and the same evaporites of the

  1. [The toxicity of different crude oils on mussel larva].

    PubMed

    Lucas, A; Le Roux, S; Pérès, J M

    1975-05-26

    Five natural oils of varied origins, mixed with sea water by stirring, have been shown to be toxic for mussel larvae, which have been contaminated during one hour. This toxicity, expressed by the mortality percentage and the growth rate after contamination, was dependent on the type and the concentration of oil. The tests were carried out on 20 h old and 5 days old larvae, and were similar and complementary.

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

    PubMed

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

    2015-01-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Larva migrans in squirrel monkeys experimentally infected with Baylisascaris potosis.

    PubMed

    Tokiwa, Toshihiro; Tsugo, Kosuke; Nakamura, Shohei; Taira, Kensuke; Une, Yumi

    2015-10-01

    Roundworms of the genus Baylisascaris are natural parasites primarily of wild carnivores, and they can occasionally cause infection in humans and animals. Infection results in visceral larva migrans and/or neural larva migrans, which can be severe or fatal in some animals. Recently, Baylisascaris nematodes isolated from kinkajous (Potos flavus) and previously referred to as Baylisascaris procyonis were renamed as Baylisascaris potosis; however, data regarding the pathogenicity of B. potosis towards animals and humans are lacking. In the present study, we experimentally infected squirrel monkeys (Saimiri sciureus) with B. potosis to determine the suitability of the monkey as a primate model. We used embryonated eggs of B. potosis at two different doses (10,000 eggs and 100,000 eggs) and examined the animals at 30 days post-infection. Histopathological examination showed the presence of B. potosis larvae and infiltration of inflammatory cells around a central B. potosis larvae in the brain, intestines, and liver. Nevertheless, the monkeys showed no clinical signs associated with infection. Parasitological examination revealed the presence of B. potosis larvae in the intestines, liver, lung, muscles, brain, kidney, and diaphragm. Our findings extend the range of species that are susceptible to B. potosis and provide evidence for the zoonotic potential of larva migrans in high dose infections.

  5. Biorheological action of Ascaris lumbricoides larvae on human erythrocytes.

    PubMed

    de León, Patricia Ponce; Del Balzo, Gonzalo; Riquelme, Bibiana

    2013-03-01

    Previous studies have shown that A. lumbricoides extracts capture sialic acid (SA) from human red blood cells (RBC). The aim of this work was to study hemorheological alterations in vitro caused by parasite larvae. The biorheological action of three larva concentrates of first and second larval stage on group O erythrocytes was analyzed by incubating the erythrocyte packed together with an equal volume of larvae (treated RBC) and PBS (control RBC). Distribution and parameters of aggregation (digital image analysis), aggregation kinetics (erythroaggregameter), and viscoelasticity (erythrodeformeter) were measured. The digital image analysis showed that all the larvae diminished the isolated cells percentage and increased the size of the formed aggregates. The aggregate formation velocity was lower in the treated than in the control. The deformability index (ID) values of treated RBC did not present variations with respect to those of the control, but a decrease in the erythrocyte elastic modulus (μ(m)) and membrane surface viscosity (η(m)) values was observed, indicating that the larvae not only induced a diminution in the membrane surface viscosity of RBC but also altered the dynamic viscoelasticity of the membrane. Experiments carried out in vitro support the conclusion that the contact between larvae and RBC produces hemorheological alterations.

  6. Incorporation of bacterial extracellular polysaccharide by black fly larvae (Simuliidae)

    USGS Publications Warehouse

    Couch, C.A.; Meyer, J.L.; Hall, R.O.

    1996-01-01

    Black fly larvae (Simulium) assimilated, with high efficiency (80-90%), bacterial extracellular polysaccharide (EPS) extracted from laboratory cultures of a pseudomonad isolated from the Ogeechee River. Incorporation was traced using 13C-labelled EPS offered to larvae as a coating on a mixture of 1-??m latex beads and kaolin particles. These EPS-coated particles were used to simulate natural particles, both living and dead. Solubility, protein, and nitrogen content of the EPS suggested it was a slime rather than a capsular polysaccharide. Glycosyl composition of the EPS was glucose and galactose in ?? and ?? linkages, with pyruvate, succinate, and possibly malonate constituent groups. To evaluate the incorporation of C derived from protein associated with the EPS matrix, feeding experiments were conducted using EPS with and without proteins extracted. Black fly larvae incorporated 7.2 ??g EPS C larva-1 d-1 from EPS that did not have proteins extracted, and 19.5 ??g EPS C larva-1 d-1 from EPS with proteins extracted. Carbon in protein that is typically associated with EPS was not solely or selectively incorporated. EPS incorporation rates are similar to rates of cellular bacterial carbon incorporation previously estimated for Ogeechee River black fly larvae. If EPS is generally available as a food resource, the importance of bacteria in detrital food webs may be underestimated by studies that examine only the consumption of bacterial cells.

  7. Sun-Compass Orientation in Mediterranean Fish Larvae

    PubMed Central

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

    2015-01-01

    Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history, larvae of coastal species have to head back to the shore at the end of their pelagic episode, to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence of coast-related cues on orientation. In this study we quantified the in situ orientation behavior of settlement-stage larvae in a temperate region, with a continuous coast and a dominant along-shore current, and inspected both coast-dependent and independent cues. We tested six species: one Pomacentridae, Chromis chromis, and five Sparidae, Boops boops, Diplodus annularis, Oblada melanura, Spicara smaris and Spondyliosoma cantharus. Over 85% of larvae were highly capable of keeping a bearing, which is comparable to the orientation abilities of tropical species. Sun-related cues influenced the precision of bearing-keeping at individual level. Three species, out of the four tested in sufficient numbers, oriented significantly relative to the sun position. These are the first in situ observations demonstrating the use of a sun compass for orientation by wild-caught settlement-stage larvae. This mechanism has potential for large-scale orientation of fish larvae globally. PMID:26308915

  8. Description of larva and puparium of Oplodontha rubrithorax (Diptera: Stratiomyidae) from the Oriental Region.

    PubMed

    Nerudová, Jana; Kovac, Damir; Tóthová, Andrea

    2015-05-01

    This is the first description of larva and puparium of Oplodontha rubrithorax (Macquart, 1838) from the Oriental Region. Larvae were found at a hot spring in North Thailand. The morphological features and cuticular structures of the larva are documented by drawings and SEM micrographs and the main characters are compared with the European O. viridula (Fabricius, 1775), the only described larva of this genus. Differences between larvae of both species were only found in pubescence. The characteristic, somewhat dilated and slightly clavate hairs on the dorsal surface of the body segments of O. viridula larva are apparently lacking in the larva of O. rubrithorax.

  9. Geology of the Delta, Escalante, Price, Richfield, and Salina 1/sup 0/ x 2/sup 0/ quadrangles, Utah

    SciTech Connect

    Thayer, P.A.

    1981-11-01

    The National Uranium Resource Evaluation (NURE) program was established to evaluate domestic uranium resources in the continental United States and to identify areas favorable for uranium exploration. The Grand Junction Office of the Department of Energy is responsible for administering the program. The Savannah River Laboratory (SRL) is responsible for hydrogeochemical and stream-sediment reconnaissance (HSSR) of 3.9 million km/sup 2/ (1,500,000 mi/sup 2/) in 37 eastern and western states. This document provides geologic and mineral resources reports for the Delta, Escalante, Price, Richfield, and Salina 1/sup 0/ x 2/sup 0/ National Topographic Map Series quadrangles, Utah. The purpose of these reports is to provide background geologic and mineral resources information to aid in the interpretation of NURE geochemical reconnaissance data. Except for the Escalante Quadrangle, each report is accompanied by a geologic map and a mineral locality map (Plates 1-8, in pocket). The US Geological Survey previously published a 1/sup 0/ x 2/sup 0/ geologic map of the Escalante Quadrangle and described the uranium deposits in the area (Hackman and Wyant, 1973). NURE hydrogeochemical and stream-sediment reconnaissance data for these quadrangles have been issued previously in some of the reports included in the references.

  10. Enhygromyxa salina gen. nov., sp. nov., a slightly halophilic myxobacterium isolated from the coastal areas of Japan.

    PubMed

    Iizuka, Takashi; Jojima, Yasuko; Fudou, Ryosuke; Tokura, Mitsunori; Hiraishi, Akira; Yamanaka, Shigeru

    2003-06-01

    Six isolates of novel marine myxobacteria, designated strains SHK-1T, SMK-1-1, SMK-1-3, SMK-10, SKK-2, and SMP-6, were obtained from various coastal samples (mud, sands and algae) collected around Japan. All of the isolates had Gram-negative rod-shaped cells, motile by gliding and grew aerobically. They showed bacteriolytic action, fruiting body formation, and NaCl requirement for growth with an optimum concentration of 1.0-2.0% (w/v). In addition, divalent cationic components of seawater, such as Mg2+ or Ca2+, were also needed for growth. The major respiratory quinone was MK-7. The G+C content of genomic DNA ranged from 65.6 to 67.4 mol% (by HPLC). The isolates shared almost identical 16S rDNA sequences, and clustered with a recently described marine myxobacterium, Plesiocystis pacifica, as their closest relative on a phylogenetic tree (95.9-96.0% similarity). Physiological and chemotaxonomic differences between the new strains and strains of the genus Plesiocystis justify the proposal of a new genus. Therefore, we propose to classify the six isolates into a new taxon of marine myxobacteria with the name, Enhygromyxa salina gen. nov., sp. nov. The type strain is SHK-1(T) (JCM 11769(T) = DSM 15217(T) = AJ 110011(T)).

  11. Directed Evolution of Dunaliella salina Ds-26-16 and Salt-Tolerant Response in Escherichia coli

    PubMed Central

    Guo, Yuan; Dong, Yanping; Hong, Xiao; Pang, Xiaonan; Chen, Defu; Chen, Xiwen

    2016-01-01

    Identification and evolution of salt tolerant genes are crucial steps in developing salt tolerant crops or microorganisms using biotechnology. Ds-26-16, a salt tolerant gene that was isolated from Dunaliella salina, encodes a transcription factor that can confer salt tolerance to a number of organisms including Escherichia coli (E. coli), Haematococcus pluvialis and tobacco. To further improve its salt tolerance, a random mutagenesis library was constructed using deoxyinosine triphosphate-mediated error-prone PCR technology, and then screened using an E. coli expression system that is based on its broad-spectrum salt tolerance. Seven variants with enhanced salt tolerance were obtained. Variant EP-5 that contained mutation S32P showed the most improvement with the E. coli transformant enduring salt concentrations up to 1.54 M, in comparison with 1.03 M for the wild type gene. Besides, Ds-26-16 and EP-5 also conferred E. coli transformant tolerance to freezing, cold, heat, Cu2+ and alkaline. Homology modeling revealed that mutation S32P in EP-5 caused the conformational change of N- and C-terminal α-helixes. Expression of Ds-26-16 and EP-5 maintained normal cellular morphology, increased the intracellular antioxidant enzymatic activity, reduced malondialdehyde content, and stimulated Nitric Oxide synthesis, thus enhancing salt tolerance to E. coli transformants. PMID:27801872

  12. Production of ectoine through a combined process that uses both growing and resting cells of Halomonas salina DSM 5928T.

    PubMed

    Lang, Ya-jun; Bai, Lin; Ren, Ya-nan; Zhang, Ling-hua; Nagata, Shinichi

    2011-03-01

    Using ectoine-excreting strain Halomonas salina DSM 5928(T), we developed a new process for high-efficiency production of ectoine, which involved a combined process of batch fermentation by growing cells and production by resting cells. In the first stage, batch fermentation was carried out using growing cells under optimal fermentation conditions. The second stage was the production phase, in which ectoine was synthesized and excreted by phosphate-limited resting cells. Optimal conditions for synthesis and excretion of ectoine during batch fermentation in a 10 l fermentor were 0.5 mol l(-1) NaCl and an initial monosodium glutamate concentration of 80 g l(-1) respectively. The pH was adjusted to 7.0 and the temperature was maintained at 33°C. In phosphate-limited resting cells medium, monosodium glutamate and NaCl concentration was 200 g l(-1) and 0.5 mol l(-1), respectively, as well as pH was 7.0. The total concentration of ectoine produced was 14.86 g l(-1), the productivity and yield of ectoine was 7.75 g l(-1) day(-1) and 0.14 g g(-1), respectively, and the percentage of ectoine excreted was 79%. These levels of ectoine production and excretion are the highest reported to date.

  13. On the mechanism of rapid plasma membrane and chloroplast envelope expansion in Dunaliella salina exposed to hypoosmotic shock

    PubMed Central

    1986-01-01

    Dunaliella salina cells rapidly diluted from their normal 1.71 M NaCl- containing growth medium into medium containing 0.86 M NaCl swelled within 2--4 min to an average volume 1.76 X larger and a surface area 1.53 X larger than found in control cells. Morphometric analysis of thin section electron micrographs revealed that certain organelles, including the chloroplast, nucleus, and some types of vacuoles, also expanded in surface area as much or more than did the entire cell. It is likely that glycerol, the most important osmotically active intracellular solute, was present in high concentration within these organelles as well as in the cytoplasm itself. Thin section and freeze- fracture electron microscopy were utilized to trace the origin of membrane material whose addition permitted the large increase in plasma membrane surface area and the equally large growth of the chloroplast outer envelope. The findings indicated that the plasma membrane's expansion resulted from its selective fusion with numerous small (less than or equal to 0.25 micron diam) vesicles prevalent throughout the cytoplasm. In contrast, new membrane added to the chloroplast outer envelope was drawn from an entirely different source, namely, elements of the endoplasmic reticulum. PMID:3941156

  14. A water-resources data-network evaluation for Monterey County, California; Phase 3, Northern Salinas River drainage basin

    USGS Publications Warehouse

    Templin, W.E.; Schluter, R.C.

    1990-01-01

    This report evaluates existing data collection networks and possible additional data collection to monitor quantity and quality of precipitation, surface water, and groundwater in the northern Salinas River drainage basin, California. Of the 34 precipitation stations identified, 20 were active and are concentrated in the northwestern part of the study area. No precipitation quality networks were identified, but possible data collection efforts include monitoring for acid rain and pesticides. Six of ten stream-gaging stations are active. Two surface water quality sites are sampled for suspended sediment, specific conductance, and chloride; one U.S. Geological Survey NASOAN site and one site operated by California Department of Water Resources make up the four active sampling locations; reactivation of 45 inactive surface water quality sites might help to achieve objectives described in the report. Three local networks measure water levels in 318 wells monthly, during peak irrigation, and at the end of the irrigation season. Water quality conditions are monitored in 379 wells; samples are collected in summer to monitor saltwater intrusion near Castroville and are also collected annually throughout the study area for analysis of chloride, specific conductance, and nitrate. An ideal baseline network would be an evenly spaced grid of index wells with a density of one per section. When baseline conditions are established, representative wells within the network could be monitored periodically according to specific data needs. (USGS)

  15. Industry-wide studies report of walk-through survey of Schilling, McCormick and Company, Incorporated, Salinas, California

    SciTech Connect

    Morawetz, J.; Steenland, K.

    1986-11-01

    A walk-through survey was conducted to determine the suitability of including Schilling, McCormick and Company, Salinas, California, in an industry-wide mortality and industrial hygiene study concerning workers with potential exposure to ethylene oxide. At this facility, spices are ground, milled, blended, mixed and filled for various customers. Et0 is used to treat unprocessed poppy seeds and Brazilian pepper as they arrive at the facility. Other spices are treated when necessary. A review of personal data on exposure levels showed that jobs where workers are exposed to 1 part per million or greater on the average include bottle dumper, receiving clerk, safety supervisor, forklift driver at warehouse, forklift driver at receiving, and Et0 chamber operator. Medical, industrial hygiene, and safety programs in effect at the facility were examined. The authors concluded that this facility meets the requirements for entry into the larger study; however, due to the limited number of person years (3000) at this facility compared to others in the study, and the cost of data collection and coding, the decision was made not to include this facility.

  16. Enhancement of Landsat images for lineament analysis in the area of the Salina Basin, New York and Pennsylvania

    USGS Publications Warehouse

    Krohn, M. Dennis

    1979-01-01

    Digital image processing of Landsat images of New York and Pennsylvania was undertaken to provide optimum images for lineament analysis in the area of the Salina Basin. Preliminary examination of Landsat images from photographic prints indicated sufficient differences between the spectral bands of the Landsat Multispectral Scanner (MSS) to warrant digital processing of both MSS band 7 and MSS band 5. Selective contrast stretching based on analysis of the Landsat MSS histograms proved to be the most important factor affecting the appearance of the images. A three-point linear stretch using the two end points and a middle point to the Landsat frequency distribution was most successful. The flexibility of the REMAPP image processing system was helpful in creating such custom-tailored stretches. An edge enhancement was tested on the MSS band 5 image, but was not used. Stereoscopic Landsat images acquired from adjacent orbits aided recognition of topographic features; the area of stereoscopic coverage could be increased by utilizing the precession of Landsat-1?s orbit . Improvements in the digitally processed scenes did affect the analysis of lineaments for the New York area; on the enhanced MSS band 5 image, an ENE trending set of lineaments is visible, which was not recognized from other images.

  17. Growth of mono- and mixed cultures of Nannochloropsis salina and Phaeodactylum tricornutum on struvite as a nutrient source.

    PubMed

    Davis, Ryan W; Siccardi, Anthony J; Huysman, Nathan D; Wyatt, Nicholas B; Hewson, John C; Lane, Todd W

    2015-12-01

    The suitability of crude and purified struvite (MgNH4PO4), a major precipitate in wastewater streams, was investigated for renewable replacement of conventional nitrogen and phosphate resources for cultivation of microalgae. Bovine effluent wastewater stone, the source of crude struvite, was characterized for soluble N/P, trace metals, and biochemical components and compared to the purified mineral. Cultivation trials using struvite as a major nutrient source were conducted using two microalgae production strains, Nannochloropsis salina and Phaeodactylum tricornutum, in both lab and outdoor pilot-scale raceways in a variety of seasonal conditions. Both crude and purified struvite-based media were found to result in biomass productivities at least as high as established media formulations (maximum outdoor co-culture yield ∼20±4gAFDW/m(2)/day). Analysis of nutrient uptake by the alga suggest that struvite provides increased nutrient utilization efficiency, and that crude struvite satisfies the trace metals requirement and results in increased pigment productivity for both microalgae strains.

  18. Low density supercritical fluids precipitation of 9-cis and all trans-β-carotenes enriched particulates from Dunaliella salina.

    PubMed

    Chen, Jian-Ren; Wu, Jia-Jiuan; Lin, Justin Chun-Te; Wang, Yuan-Chuen; Young, Chiu-Chung; Shieh, Chwen-Jen; Hsu, Shih-Lan; Chang, Cheih-Ming J

    2013-07-19

    In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-β-carotenes from Dunaliella salina. Total concentration of 9-cis (134.7mg/g) and trans-β-carotene (204.2mg/g) was increased from 338.9mg/g of the ultrasonic extract to 859.7mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1mg/g (355.6 for 9-cis and 576.5 for trans) of total β-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total β-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-β-carotenes by low-density SAS was proved to be feasible and environmental benign.

  19. Growth of mono- and mixed cultures of Nannochloropsis salina and Phaeodactylum tricornutum on struvite as a nutrient source

    SciTech Connect

    Davis, Ryan W.; Siccardi, Anthony J.; Huysman, Nathan D.; Wyatt, Nicholas B.; Hewson, John C.; Lane, Todd W.

    2015-09-26

    In this paper, the suitability of crude and purified struvite (MgNH4PO4), a major precipitate in wastewater streams, was investigated for renewable replacement of conventional nitrogen and phosphate resources for cultivation of microalgae. Bovine effluent wastewater stone, the source of crude struvite, was characterized for soluble N/P, trace metals, and biochemical components and compared to the purified mineral. Cultivation trials using struvite as a major nutrient source were conducted using two microalgae production strains, Nannochloropsis salina and Phaeodactylum tricornutum, in both lab and outdoor pilot-scale raceways in a variety of seasonal conditions. Both crude and purified struvite-based media were found to result in biomass productivities at least as high as established media formulations (maximum outdoor co-culture yield ~20 ± 4 g AFDW/m2/day). Finally, analysis of nutrient uptake by the alga suggest that struvite provides increased nutrient utilization efficiency, and that crude struvite satisfies the trace metals requirement and results in increased pigment productivity for both microalgae strains.

  20. Transcript levels of phytoene desaturase gene in Dunaliella salina Teod. as affected by PbS nanoparticles and light intensity

    PubMed Central

    Zamani, Hajar; Moradshahi, Ali

    2016-01-01

    Phytoene synthase (Psy) and Phytoene desaturase (Pds) are the first two regulatory enzymes in the carotenoids biosynthetic pathway. The genes Psy and Pds are under transcriptional control in many photosynthetic organisms. In the present study, using quantitative real time- PCR (qRT-PCR), the effects of uncoated and gum-Arabic coated PbS nanoparticles (GA-coated PbS NPs) and light intensity on the mRNA levels of Pds were investigated. Relative to mRNA level of Pds at 100 µmol photon m-2 s-1 light intensity (control culture), 2.2-fold increase in transcript levels occurred after 12 h of exposure to higher light intensity, which is significantly (P<0.05) different compared to control. After 48 h of exposure, the mRNA level of Pds was reduced to that in control. This indicates that light intensity regulates Pds at the mRNA level. In the presence of uncoated and GA-coated PbS NPs, the transcript levels of Pds were decreased over time, with uncoated PbS NPs having more inhibitory effects on mRNA levels compared to GA- coated PbS NPs. This shows that PbS NPs have adverse effects on transcription or post transcriptional processing and coating nanoparticles with biopolymers reduces their toxicity to organisms. Being under control, it seems that genetic manipulation of Pds may result in increased biotechnological production of carotenoids by D. salina. PMID:28097172