A genus of GRAM-POSITIVE ENDOSPORE-FORMING BACTERIA in the family Pasteuriaceae. It is transmitted via soil or waterborne SPORES.
Toxicity Tests, Acute
Water containing no significant amounts of salts, such as water from RIVERS and LAKES.
Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.
The sequence of transfers of matter and energy from organism to organism in the form of FOOD. Food chains intertwine locally into a food web because most organisms consume more than one type of animal or plant. PLANTS, which convert SOLAR ENERGY to food by PHOTOSYNTHESIS, are the primary food source. In a predator chain, a plant-eating animal is eaten by a larger animal. In a parasite chain, a smaller organism consumes part of a larger host and may itself be parasitized by smaller organisms. In a saprophytic chain, microorganisms live on dead organic matter.
The enrichment of a terrestrial or aquatic ECOSYSTEM by the addition of nutrients, especially nitrogen and phosphorus, that results in a superabundant growth of plants, ALGAE, or other primary producers. It can be a natural process or result from human activity such as agriculture runoff or sewage pollution. In aquatic ecosystems, an increase in the algae population is termed an algal bloom.
A form-genus of CYANOBACTERIA in the order Chroococcales. Many species are planktonic and possess gas vacuoles.
The study of ENVIRONMENTAL POLLUTION and the toxic effects of ENVIRONMENTAL POLLUTANTS on the ECOSYSTEM. The term was coined by Truhaut in 1969.
Water Pollutants, Chemical
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
Free-floating minute organisms that are photosynthetic. The term is non-taxonomic and refers to a lifestyle (energy utilization and motility), rather than a particular type of organism. Most, but not all, are unicellular algae. Important groups include DIATOMS; DINOFLAGELLATES; CYANOBACTERIA; CHLOROPHYTA; HAPTOPHYTA; CRYPTOMONADS; and silicoflagellates.
A class of EUKARYOTA (traditionally algae), characterized by biflagellated cells and found in both freshwater and marine environments. Pigmentation varies but only one CHLOROPLAST is present. Unique structures include a nucleomorph and ejectosomes.
Life Cycle Stages
The continuous sequence of changes undergone by living organisms during the post-embryonic developmental process, such as metamorphosis in insects and amphibians. This includes the developmental stages of apicomplexans such as the malarial parasite, PLASMODIUM FALCIPARUM.
An order of mostly marine CRUSTACEA containing more than 5500 species in over 100 families. Like ISOPODA, the other large order in the superorder Peracarida, members are shrimp-like in appearance, have sessile compound eyes, and no carapace. But unlike Isopoda, they possess thoracic gills and their bodies are laterally compressed.
The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.
Group of fish under the superorder Acanthopterygii, separate from the PERCIFORMES, which includes swamp eels, mullets, sticklebacks, seahorses, spiny eels, rainbowfishes, and KILLIFISHES. The name is derived from the six taxa which comprise the group. (From http://www.nanfa.org/articles/Elassoma/elassoma.htm, 8/4/2000)
The largest order of CRUSTACEA, comprising over 10,000 species. They are characterized by three pairs of thoracic appendages modified as maxillipeds, and five pairs of thoracic legs. The order includes the familiar shrimps, crayfish (ASTACOIDEA), true crabs (BRACHYURA), and lobsters (NEPHROPIDAE and PALINURIDAE), among others.
Influenza A Virus, H3N8 Subtype
The branch of science concerned with the interrelationship of organisms and their ENVIRONMENT, especially as manifested by natural cycles and rhythms, community development and structure, interactions between different kinds of organisms, geographic distributions, and population alterations. (Webster's, 3d ed)
Hormones produced by invertebrates, usually insects, mollusks, annelids, and helminths.
A phylum of photosynthetic EUKARYOTA bearing double membrane-bound plastids containing chlorophyll a and b. They comprise the classical green algae, and represent over 7000 species that live in a variety of primarily aquatic habitats. Only about ten percent are marine species, most live in freshwater.
Periodic casting off FEATHERS; HAIR; or cuticle. Molting is a process of sloughing or desquamation, especially the shedding of an outer covering and the development of a new one. This phenomenon permits growth in ARTHROPODS, skin renewal in AMPHIBIANS and REPTILES, and the shedding of winter coats in BIRDS and MAMMALS.
The systematic study of the complete DNA sequences (GENOME) of organisms.
The discipline studying genetic composition of populations and effects of factors such as GENETIC SELECTION, population size, MUTATION, migration, and GENETIC DRIFT on the frequencies of various GENOTYPES and PHENOTYPES using a variety of GENETIC TECHNIQUES.
DNA, Ribosomal Spacer
Lethal Dose 50
Chemical substances that are foreign to the biological system. They include naturally occurring compounds, drugs, environmental agents, carcinogens, insecticides, etc.
The number of mutations that occur in a specific sequence, GENE, or GENOME over a specified period of time such as years, CELL DIVISIONS, or generations.
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Chemical substances, excreted by an organism into the environment, that elicit behavioral or physiological responses from other organisms of the same species. Perception of these chemical signals may be olfactory or by contact.
Phosphorus used in foods or obtained from food. This element is a major intracellular component which plays an important role in many biochemical pathways relating to normal physiological functions. High concentrations of dietary phosphorus can cause nephrocalcinosis which is associated with impaired kidney function. Low concentrations of dietary phosphorus cause an increase in calcitriol in the blood and osteoporosis.
The class Insecta, in the phylum ARTHROPODA, whose members are characterized by division into three parts: head, thorax, and abdomen. They are the dominant group of animals on earth; several hundred thousand different kinds having been described. Three orders, HEMIPTERA; DIPTERA; and SIPHONAPTERA; are of medical interest in that they cause disease in humans and animals. (From Borror et al., An Introduction to the Study of Insects, 4th ed, p1)
A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc.
Common name for a number of different species of fish in the family Cyprinidae. This includes, among others, the common carp, crucian carp, grass carp, and silver carp.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
One of the three domains of life (the others being BACTERIA and ARCHAEA), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including ANIMALS; PLANTS; FUNGI; and various algae and other taxa that were previously part of the old kingdom Protista.
A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.
Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Sequence Analysis, DNA
The protein complement of an organism coded for by its genome.
The functional hereditary units of INSECTS.
A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)
Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987)
The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.
Sequence Homology, Nucleic Acid
Amino Acid Sequence
Gene Expression Regulation
Molecular Sequence Annotation
The addition of descriptive information about the function or structure of a molecular sequence to its MOLECULAR SEQUENCE DATA record.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.
Gene Expression Profiling
The systematic study of the complete complement of proteins (PROTEOME) of organisms.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
Tandem Mass Spectrometry
A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
Electrophoresis, Polyacrylamide Gel
A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.
Dose-Response Relationship, Drug
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Databases containing information about PROTEINS such as AMINO ACID SEQUENCE; PROTEIN CONFORMATION; and other properties.
Polymerase Chain Reaction
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Morphological and compositional changes in a planktonic bacterial community in response to enhanced protozoan grazing. (1/365)We analyzed changes in bacterioplankton morphology and composition during enhanced protozoan grazing by image analysis and fluorescent in situ hybridization with group-specific rRNA-targeted oligonucleotide probes. Enclosure experiments were conducted in a small, fishless freshwater pond which was dominated by the cladoceran Daphnia magna. The removal of metazooplankton enhanced protozoan grazing pressure and triggered a microbial succession from fast-growing small bacteria to larger grazing-resistant morphotypes. These were mainly different types of filamentous bacteria which correlated in biomass with the population development of heterotrophic nanoflagellates (HNF). Small bacterial rods and cocci, which showed increased proportion after removal of Daphnia and doubling times of 6 to 11 h, belonged nearly exclusively to the beta subdivision of the class Proteobacteria and the Cytophaga-Flavobacterium cluster. The majority of this newly produced bacterial biomass was rapidly consumed by HNF. In contrast, the proportion of bacteria belonging to the gamma and alpha subdivisions of the Proteobacteria increased throughout the experiment. The alpha subdivision consisted mainly of rods that were 3 to 6 microm in length, which probably exceeded the size range of bacteria edible by protozoa. Initially, these organisms accounted for less than 1% of total bacteria, but after 72 h they became the predominant group of the bacterial assemblage. Other types of grazing-resistant, filamentous bacteria were also found within the beta subdivision of Proteobacteria and the Cytophaga-Flavobacterium cluster. We conclude that the predation regimen is a major structuring force for the bacterial community composition in this system. Protozoan grazing resulted in shifts of the morphological as well as the taxonomic composition of the bacterial assemblage. Grazing-resistant filamentous bacteria can develop within different phylogenetic groups of bacteria, and formerly underepresented taxa might become a dominant group when protozoan predation is the major selective pressure. (+info)
Heterogeneity and differential expression under hypoxia of two-domain hemoglobin chains in the water flea, Daphnia magna. (2/365)Hemoglobin (Hb) purified from the water flea, Daphnia magna, reared under hypoxia was analyzed by two-dimensional gel electrophoresis. The Hb was shown to be composed of six major subunit chain species (designated as DHbA to DHbF). The NH2-terminal amino acid sequences of DHbA, DHbB, DHbC, and DHbF are different from one another, indicating that at least four Hb genes are present in D. magna. The NH2-terminal amino acid sequences of DHbD and DHbE are the same as those of DHbA and DHbB, respectively. The six Hb chains were also found in the animal reared under normoxia in small amounts and with altered composition; the extent of decrease under normoxia was higher in the amounts of DHbC, DHbD, and DHbF than those of others. These results indicate that the Hb genes are differentially regulated by the ambient oxygen concentration. Four Hb genes constituting a cluster in the order, dhb4, dhb3, dhb1, and dhb2, were found on the chromosome of D. magna. The complete nucleotide sequences of the dhb1, dhb2, and dhb3 genes and their cDNAs showed that the genes have a seven-exon, six-intron structure. The structure consists of an intron separating an exon encoding a secretory signal sequence, two large repeated regions of a three-exon, two-intron structure that encode each a domain containing a heme-binding site, and an intron bridging the two repeated regions. The deduced amino acid sequences of the gene products showed higher than 79% identity to one another and showed unique features conserved in D. magna Hb chains. The analysis also suggested that DHbB (or DHbE), DHbF, and DHbC are encoded by the dhb1, dhb2, and dhb3 genes, respectively. (+info)
Model ecosystem evaluation of the environmental impacts of the veterinary drugs phenothiazine, sulfamethazine, clopidol, and diethylstilbestrol. (3/365)Four veterinary drugs of dissimilar chemical structures were evaluated for environmental stability and penchant for bioaccumulation. The techniques used were (1) a model aquatic ecosystem (3 days) and (2) a model feedlot ecosystem (33 days) in which the drugs were introduced via the excreta of chicks or mice. The model feedlot ecosystem was supported by metabolism cage studies to determine the amount and the form of the drug excreted by the chicks or mice. Considerable quantities of all the drugs were excreted intact or as environmentally short-lived conjugates. Diethylstilbestrol (DES) and Clopidol were the most persistent molecules, but only DES bioaccumulated to any appreciable degree. Phenothiazine was very biodegradable; sulfamethazine was relatively biodegradable and only accumulated in the organisms to very low levels. Data from the aquatic model ecosystem demonstrated a good correlation between the partition coefficients of the drugs and their accumulation in the fish. (+info)
Daphnia pulex didomain hemoglobin: structure and evolution of polymeric hemoglobins and their coding genes. (4/365)The high-molecular-weight extracellular hemoglobin of Daphnia pulex is composed of at least three different didomain globin chains. The primary structure of one of these chains was determined at the protein and cDNA levels. Each globin domain of the polypeptide chain displays the standard structural characteristics. The first domain is preceded by a 30-residue extension containing an 18-residue unprecedented threonine-rich segment and a 12-residue preA segment which is homologous to the preA segments of other nonvertebrate globin chains. Both domains are linked together by a preA' segment, which is homologous to other preA segments and lacks the threonine-rich segment. Dimerization of the globin chains by the formation of a disulphide bridge linking the unique cysteines near the amino-termini results in a covalent, vertebrate-like tetradomain structure. The flexible amino-terminal extension most likely facilitates dimerization. The gene coding for this globin chain is interrupted by six small introns. Each domain displays two intradomain introns at the conserved positions B12.2 and G7.0. A precoding intron occurs at position preA(-27.0) and a bridge intron at occurs preA'(-13.2). We propose a crossover event as the most likely mechanism for duplication. Arthropod globin trees reflect the added effects of gene diversification, gene duplication, and species evolution. The position of monodomain intracellular globins in the tree suggests that they resemble the ancestral globin more than the derived didomain extracellular globins do. (+info)
Genetic differentiation among Oregon lake populations of the Daphnia pulex species complex. (5/365)Gene flow among invertebrate populations inhabiting bodies of nonflowing freshwater such as ponds or lakes must at some stage involve transport across habitat unsuitable for adult stages. Consequently the potential for interpopulational differentiation is high in these species, yet empirical studies of lake populations of Cladocerans such as Daphnia have failed to reveal high levels of genetic distinctiveness among populations and have led to much speculation about how these populations exchange genes and remain cohesive evolutionary units. In this study we surveyed 42 Oregon lake populations of Daphnia from the D. pulex species complex for genetic variation within the mitochondrial DNA control region. We have used this data to test the relative abilities of various ecological factors to explain the observed patterns in genetic differentiation among lakes. Despite limited genetic variation detected among our samples--11 very similar RFLP-defined mtDNA genotypes from 388 individuals--analyses of nucleotide variance using analogs to Wright's F statistics indicate that when multilake populations are defined in terms of the river drainage basin to which they belong, strong and significant amounts of among-population genetic variation can be detected at this locus (F(ST) estimates between 0.5 and 0.6). In contrast, we fail to detect consistent significant among-population variation when populations are defined on the basis of regional physical geography, bird migratory flyways, or lake trophic status. The manner in which the data are compiled, that is, whether RFLPs or nucleotide sequences are used, has little effect on the overall conclusions, yet it is clear that nucleotide sequence data would lower the standard errors of F(ST) estimates. We propose that periodic widescale flooding during the late Pleistocene may be an important mechanism to homogenize genetic differences among lake Daphnia continent-wide south of the southern-most extent of Pleistocene glaciation. (+info)
Avoiding the cost of males in obligately asexual Daphnia pulex (Leydig). (6/365)Asexual organisms are thought to gain an advantage by avoiding the cost of producing males. In the cladoceran Daphnia pulex (Leydig), male production is determined by the environment and is independent of the origin of the asexual obligate parthenogens from the sexual cyclical parthenogens. If there is a cost to producing males, successful obligate parthenogens should have reduced or eliminated male production. Field and laboratory observations showed that obligate parthenogens have much-reduced male production compared to cyclical parthenogens. Although the reduction or elimination of males in the obligate parthenogens suggests that the cost of males is avoided, the coexistence of sexual and asexual forms of D. pulex may be partially explained by cyclical parthenogens compensating for the cost of males by having greater fecundity. In addition, the absence of a mating constraint for the obligate parthenogens may favour an increased allocation to asexual diapausing eggs earlier in the season compared to the cyclical parthenogens which require mating with males to produce sexual diapausing eggs. No difference in the production of diapausing eggs was observed, probably because males were abundant in populations of cyclical parthenogens and do not appear to limit the production of sexual diapausing eggs. D. pulex is a useful system for determining the ecological consequences of abandoning sexual reproduction and explaining the coexistence of sexual and asexual forms of a species. (+info)
Molecular systematics of European Hyalodaphnia: the role of contemporary hybridization in ancient species. (7/365)We examined phylogenetic relationships among Daphnia using mitochondrial DNA (mtDNA) sequences from the small subunit ribosomal RNA (12S), cytochrome c oxidase subunit I and nuclear DNA sequences from the first and second internal transcribed spacer representing 1612 base positions. Phylogenetic analyses using several species of the three main Daphnia subgenera, Ctenodaphnia, Hyalodaphnia and Daphnia, revealed that the Hyalodaphnia are a monophyletic sister group of the Daphnia. Most Hyalodaphnia species occur on one continent, whereas only three are found in North America and Europe. Endemicity of species is associated with variation in thermal tolerance and habitat differentiation. Although many species of the Hyalodaphnia are known to hybridize in nature, mtDNA divergence is relatively high ca. 9%) compared to other hybridizing arthropods (ca. 3%). Reproductive isolation in Daphnia seems to evolve significantly slower than genetic isolation. We related these findings to what is known about the ecology and genetics of Daphnia in order to better understand the evolutionary diversification of lineages. The relationship of these data to phylogenetic patterns is discussed in the context of speciation processes in Daphnia. (+info)
Flavobacterium psychrophilum, invasion into and shedding by rainbow trout Oncorhynchus mykiss. (8/365)The infection route of Flavobacterium psychrophilum into rainbow trout Oncorhynchus mykiss was studied using bath and cohabitation challenges as well as oral challenge with live feed as a vector. Additionally, the number of bacterial cells shed by infected fish into the surrounding water was determined in the cohabitation experiment and in challenge experiments at 3 different water temperatures. The experiments showed that skin and skin mucus abrasion dramatically enhanced the invasion of F. psychrophilum into the affected fish in bath and cohabitation challenges. Disruption of the skin is discussed as an important invasion route for F. psychrophilum into the fish. The shedding rate of F. psychrophilum by infected fish was associated with water temperature and the mortality of the infected fish. High numbers of F. psychrophilum cells were released into the water by dead rainbow trout during a long time period compared to the numbers of cells shed by live fish. The results emphasise the importance of removing dead and moribund fish from rearing tanks in order to diminish the infection pressure against uninfected fish in commercial fish farms. In immunohistochemical examinations of organs and tissues of orally infected fish, F. psychrophilum cells were detected in only 1 fish out of 31 studied. Mortality of the orally challenged fish was not observed in the experiment. (+info)
474. Bianchini, A. and Wood, C.M. (2008) Sodium uptake in different life stages of crustaceans: The water flea Daphnia magna...
474. Bianchini, A. and Wood, C.M. (2008) Sodium uptake in different life stages of crustaceans: The water flea Daphnia magna Strauss. J. Exp. Biol. 211 pp: 539-547. (PDF). ...
Recommendation for Spiny Water Flea Spread Prevention in Lake Champlain - Lake Champlain Basin Program
Grand Isle, VT - The Lake Champlain Basin Aquatic Invasive Species Rapid Response Task Force has determined that eradication of spiny water flea in Lake Champlain is not technically feasible. Spread prevention measures should be implemented as soon as possible.. The Rapid Response Task Force reviewed the technical feasibility of preventing the spiny water flea from spreading from Lake Champlain to other inland water bodies. There are no known methods to eradicate spiny water flea once they have been detected in a water body. Initial sampling has confirmed its presence at multiple lake stations in the Main Lake segment of Lake Champlain. In 2012, spiny water flea was discovered in both the Champlain Canal and Lake George. Spiny water fleas have been detected in the southern Adirondacks in Great Sacandaga Lake (2008), Peck Lake (2009), and Stewarts Bridge Reservoir and Sacandaga Lake (2010). This summer they were detected in Lakes Piseco and Pleasant (2014). It is unknown how the spiny water flea ...
Composition and stability of the microbial community inside the digestive tract of the aquatic crustacean daphnia magna
rdf:RDF xmlns:dcterms=http://purl.org/dc/terms/ xmlns:dc=http://purl.org/dc/elements/1.1/ xmlns:rdf=http://www.w3.org/1999/02/22-rdf-syntax-ns# xmlns:bibo=http://purl.org/ontology/bibo/ xmlns:dspace=http://digital-repositories.org/ontologies/dspace/0.1.0# xmlns:foaf=http://xmlns.com/foaf/0.1/ xmlns:void=http://rdfs.org/ns/void# xmlns:xsd=http://www.w3.org/2001/XMLSchema# , ,rdf:Description rdf:about=https://kops.uni-konstanz.de/rdf/resource/123456789/17951, ,dcterms:abstract xml:lang=eng,Small filter-feeding zooplankton organisms like the cladoceran Daphnia spp. are key members of freshwater food webs. Although several interactions between Daphnia and bacteria have been investigated, the importance of the microbial communities inside Daphnia guts has been studied only poorly so far. In the present study, we characterised the bacterial community composition inside the digestive tract of a laboratory-reared clonal culture of Daphnia magna using 16S rRNA gene libraries and ...
Development of a microinjection system for RNA interference in the water flea Daphnia pulex | BMC Biotechnology | Full Text
The ubiquitous, freshwater microcrustacean Daphnia pulex provides a model system for both human health research and monitoring ecosystem integrity. It is the first crustacean to have a well annotated, reference genome assembly that revealed an unusually high gene count highlighted by a large gene orphanage,-i.e., previously uncharacterized genes. Daphnia are capable of either clonal or sexual reproduction, making them ideally suited for genetic manipulation, but the establishment of gene manipulation techniques is needed to accurately define gene functions. Although previous investigations developed an RNA interference (RNAi) system for one congener D. magna, these methods are not appropriate for D. pulex because of the smaller size of their early embryos. In these studies, we develop RNAi techniques for D. pulex by first determining the optimum culture conditions of their isolated embryos and then applying these conditions to the development of microinjection techniques and proof-of-principle RNAi
The Population Dynamics of Daphnia At Constant Food Supply: a Review, Re-Evaluation and Analysis of Experimental Series From...
Data on the population dynamics of five Daphnia species, viz. D. galeata mendotae, D. obtusa, D. pulicaria, D. pulex and D. magna, were collected from the literature. The experiments with constant food input were re-analysed for the oscillatory behaviour of the populations. Some populations appear to stabilize, whereas others continue to fluctuate. Some fluctuations are apparently caused by external factors. A decline to far below the average population size is always followed by a large population overshoot. Even populations that tend to stabilize do so by way of a series of damped oscillations. The oscillation period depends on, among other things, the Daphnia species, and increases with its size. Sometimes the same feeding regime leads to an equal or greater population size for a larger Daphnia species. This suggests that the chosen food species was not equally suitable for the two Daphnia species. No effect of crowding on the population size of Daphnia is found.
Water flea eye, light micrograph - Stock Image C028/9152 - Science Photo Library
Water flea eye. Polarised light micrograph of the eye of a Sida crystallina water flea. Water fleas (order Cladocera) are small crustaceans, commonly found in fresh water. They are filter feeders that ingest algae, protozoa or organic matter, and are a constituent of plankton. Magnification: x400 when printed 10 centimetres wide. - Stock Image C028/9152
Differing Daphnia magna assimilation efficiencies for terrestrial, bacterial, and algal carbon and fatty acids
There is considerable interest in the pathways by which carbon and growth-limiting elemental and biochemical nutrients are supplied to upper trophic levels. Fatty acids and sterols are among the most important molecules transferred across the plant-animal interface of food webs. In lake ecosystems, in addition to phytoplankton, bacteria and terrestrial organic matter are potential trophic resources for zooplankton, especially in those receiving high terrestrial organic matter inputs. We therefore tested carbon, nitrogen, and fatty acid assimilation by the crustacean Daphnia magna when consuming these resources. We fed Daphnia with monospecific diets of high-quality (Cryptomonas marssonii) and intermediate-quality (Chlamydomonas sp. and Scenedesmus gracilis) phytoplankton species, two heterotrophic bacterial strains, and particles from the globally dispersed riparian grass, Phragmites australis, representing terrestrial particulate organic carbon (t-POC). We also fed Daphnia with various mixed ...
Determining lower threshold concentrations for synergistic effects
Though only occurring rarely, synergistic interactions between chemicals in mixtures have long been a point of focus. Most studies analyzing synergistic interactions used unrealistically high chemical concentrations. The aim of the present study is to determine the threshold concentration below which proven synergists cease to act as synergists towards the aquatic crustacean Daphnia magna. To do this, we compared several approaches and test-setups to evaluate which approach gives the most conservative estimate for the lower threshold for synergy for three known azole synergists. We focus on synergistic interactions between the pyrethroid insecticide, alpha-cypermethrin, and one of the three azole fungicides prochloraz, propiconazole or epoxiconazole measured on Daphnia magna immobilization. Three different experimental setups were applied: A standard 48h acute toxicity test, an adapted 48h test using passive dosing for constant chemical exposure concentrations, and a 14-day test. Synergy was ...
Inundation frequency and viability of microcrustacean propagules in soils of temporary aquatic habitats of lower Okavango Delta...
Microcrustacean emergence from the dry sediments is an important colonization pathway that allows these microfauna to recover and repopulate temporary aquatic habitats after months or years of dryness. Viable microcrustacean propagules in sediments of three different temporary aquatic habitats - rainpools located within the rarely flooded portions, frequently flooded floodplains and rarely flooded floodplains - were assessed experimentally by flooding the soils. Three major groups of microcrustaceans - cladocerans, copepods and ostracods - emerged from the sediments. Species richness and mean total numbers of emerged microcrustaceans per sample varied across the studied temporary aquatic habitats (Kruskal-Wallis, p , 0.05). Both species richness and mean total number of emerged microcrustacean per sample were lowest in sediments of rarely flooded floodplains. The highest species richness of microcrustaceans emerged from the treatments with soils of the frequently flooded floodplains. The mean ...
Aging of TiO2 Nanoparticles Transiently Increases Their Toxicity to the Pelagic Microcrustacean Daphnia magna
During their aquatic life cycle, nanoparticles are subject to environmentally driven surface modifications (e.g. agglomeration or coating) associated with aging. Although the ecotoxicological potential of nanoparticles might be affected by these processes, only limited information about the potential impact of aging is available. In this context, the present study investigated acute (96 h) and chronic (21 d) implications of systematically aged titanium dioxide nanoparticles (nTiO2; ~90 nm) on the standard test species Daphnia magna by following the respective test guidelines. The nTiO2 were aged for 0, 1, 3 and 6 d in media with varying ionic strengths (Milli-Q water: approx. 0.00 mmol/L and ASTM: 9.25 mmol/L) in the presence or absence of natural organic matter (NOM). Irrespective of the other parameters, aging in Milli-Q did not change the acute toxicity relative to an unaged control. In contrast, 6 d aged nTiO2 in ASTM without NOM caused a fourfold decreased acute toxicity. Relative to the 0 d aged
Dopamine as a key to plasticity | Proceedings of the Royal Society of London B: Biological Sciences
Predation is a primary force driving adaptation in prey. When predatory threats are fluctuating in natural environments, inducible defences may evolve in prey organisms. For example, behavioural adaptations reduce the chance of predator encounter and life-history changes increase survival chances under size selective predation . Prominent examples of inducible defences are the various defensive morphological traits observed in the model freshwater crustacean Daphnia. Several Daphnia species display spectacular morphological defences [2,3] including crowns of thorns , spines , crests  and helmets [7-9]. All these defensive strategies are induced via predator-specific chemical cues known as kairomones. The chemical perception of kairomones initiates a series of internal physiological reactions including neuronal signal integration  and subsequent conversion into endocrine agents [11-13]. These substances in turn modulate developmental changes, which result in the growth of a ...
Water Flea Waltz
(YouTube link) Aint science wonderful? Here is a video of the microscopic water flea performing a little musical ditty. -via Improbable Research, where youll find an additional video of a water flea playing with a toy....
Functional inference by ProtoNet family tree: the uncharacterized proteome of Daphnia pulex | BMC Bioinformatics | Full Text
Daphnia pulex (Water flea) is the first fully sequenced crustacean genome. The crustaceans and insects have diverged from a common ancestor. It is a model organism for studying the molecular makeup for coping with the environmental challenges. In the complete proteome, there are 30,550 putative proteins. However, about 10,000 of them have no known homologues. Currently, the UniProtoKB reports on 95% of the Daphnias proteins as putative and uncharacterized proteins. We have applied ProtoNet, an unsupervised hierarchical protein clustering method that covers about 10 million sequences, for automatic annotation of the Daphnias proteome. 98.7% (26,625) of the Daphnia full-length proteins were successfully mapped to 13,880 ProtoNet stable clusters, and only 1.3% remained unmapped. We compared the properties of the Daphnias protein families with those of the mouse and the fruitfly proteomes. Functional annotations were successfully assigned for 86% of the proteins. Most proteins (61%) were mapped to only
Daphnia (Daphnia pulex) | Tropical Fish Keeping
Daphnia (Daphnia pulex) is the most common freshwater species known to tropical fish keeping enthusiasts as Water Fleas, Moina, or Water Bugs.
Propofol - Janusinfo.se
Persistence OECD guideline 301F: The results showed that propofol is not biodegradable, with ,5% biodegradation after 28 days. However, ,91% removal of propofol from the aqueous phase was observed, which was noted at the time as being possibly due to adsorption to the solid phase.. ISO Guideline 11734: The results showed that propofol was not biodegradable under the anaerobic conditions of the test, although a degree of elimination was observed.. The medicine is potentially persistent.. Bioaccumulation: Log P = 3.9 (at pH 8). BCF 28 D = 27 (at 2 μg/L) and 28 D = 26 (at 0.2 μg/L).. Toxicity: There are data for 3 trophic levels, most sensitive crustacean (Daphnia magna) NOEC chronic toxicity 230 microg/L. ...
Microbial levan and pullulan as potential protective agents for reducing adverse effects of copper on Daphnia magna and Vibrio...
Microbial polysaccharides, due to their unique physiochemical properties, have found application in the food industry, cosmetics, pharmacy and medicine. In the environment, microbes can use polysaccharides to alleviate the adverse effects of heavy metals in their close proximity. This adaptive property shows interesting potential for bioremediation. Herein, the effects of the exopolysaccharides (EPS) levan, produced by the bacterium Bacillus licheniformis NS032 and pullulan, produced by the fungus Aureobasidium pullulans CH-1 in the presence of copper (Cu2+) have been investigated for the first time on antioxidant enzyme activity, respiration and Cu2+ bioaccumulation of Daphnia magna as well as the bioluminescence of Vibrio fischeri. Both EPS decreased toxicity of Cu2+ in the acute test with D. magna. The activity of catalase (CAT) was significantly diminished after acute exposure to Cu2+ in comparison to treatments with Cu2+ and EPS, while in the prolonged acute exposure the CAT activ...ity did ...
Investigating the Effects of Water Pollution on Daphnia magna
This Iowan eighth-grader turned her love of nature into a long-term study of water pollution. Shes continuing to investigate the mysterious growths that have formed on her Daphnia magna.
The effect of caffeine on the heart rate - A-Level Science - Marked by Teachers.com
Introduction. The effect of caffeine on heart rate Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Introduction: Plants produce caffeine as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia have all been used for hundreds of years to produce pick me up drinks containing caffeine. These days, caffeine is also used as a flavour enhancer in a wide range of cola and other soft drinks. ...read more. Middle. This can lead to heart and circulation problems. Daphnia are small, planktonic crustaceans commonly called water fleas because of their saltatory swimming style (although fleas are insects and thus only very distantly related). They live in various aquatic environments ranging from acidic swamps to freshwater lakes, ponds, streams and rivers. Hypothesis: Caffeine will increase the heart rate of the Daphnia (water fleas). Equipment needed: * Culture of Daphnia (water fleas) * Cavity slides * Dropping pipettes * Distilled water and pond ...
Local and regional founder effects in lake zooplankton persist after thousands of years despite high dispersal potential -...
We reconstructed the genetic structure of a planktonic crustacean Daphnia longispina living in high mountain lakes and ponds in the Pyrenees to investigate whether it was shaped by persistent founder effects originating shortly after the last glacial maximum or by ongoing dispersal and effective migration (gene flow). We found that the genetic structure can largely be explained by a single colonization event following gradual deglaciation of the Pyrenees c. 10-15 000 years ago. Nuclear genetic diversity declined steeply from southeast to northwest, suggestive of serial colonization of available habitats with advancing deglaciation. The spatial genetic structure suggests that founder effects were major determinants of the present-day diversity, both at the catchment level and at the level of individual water bodies, further supporting extremely low effective migration rates. This study reveals a prime example of a founder effect that is both long-lasting and maintained at small spatial scales. ...
Previous Years - Munich Graduate Program for Evolution, Ecology and Systematics - LMU Munich
To study on a spatial scale the composition of Daphnia populations we surveyed Daphnia populations north and south of the Swiss Alps. We found that Lakes North of the Alps were invaded with one species (D. galeata) and hypothesize that lakes south of the Alps were invaded with D. longispina. A first life history experiment shows some evidence for this hypothesis. Further, testing of this hypothesis needs to come from sediment cores from lakes from the south side of the alps. I will present recent data about these studies.. 10.06.2013. Urban Friberg - Genetics of sexual dimorphism. Evolutionary Biology Centre, Uppsala University, Sweden. Abstract: Evolution of sexual dimorphism (SD) is a paradox. On the one hand it shouldbe constrained, because it is restricted to occur only through geneexpression and because it relies on gene expression having a sex-specificgenetic architecture. On the other hand SD is common and SD traits are amongthose that evolve the fastest. How is this possible? Is ...
Development of molecular tools to study Daphnia - parasite dynamics
Evolutionary dynamics of hosts and their parasites are complex processes. In order to study these processes on genotype level, reliable molecular tools have to be developed. The goal of this thesis was to develop such tools for freshwater crustaceans - Daphnia longispina species complex and its parasites. On one hand, from the host side - an interspecific hybridization plays an important role. For tracing community dynamics and reticulate evolution in such a hybrid species complex, long-term comparative studies of natural populations are necessary. In order to conduct such a study, it is essential to access historical samples. These samples are usually suffering from low DNA quality due to the preservation chemical such as formaldehyde or denaturated ethanol, therefore traditional genotyping through length-based markers (such as microsatellites or allozymes) proved to be insufficient. For circumventing these issues, SNP- based markers were developed. Based on transcriptome data of one species ...
Acute Toxicity Evaluation to Daphnia magna of Disease Resistant(OsCK1) Rice | Korea Science
Acute Toxicity Evaluation to Daphnia magna of Disease Resistant(OsCK1) Rice - Daphnia magna;Disease resistant transgenic rice;Risk assessment;
DiVA - Search result
The common evergreen dwarf shrub Empetrum hormaphroditum has influence on the functioning of boreal terrestrial ecosystems in northern Sweden. The negative effects of E. hermaphroditum are partly attributed to the production of the dihydrostilbene, batatasin-III, which is released from leaves and litter by rain and snowmelt. In this study, we investigated whether batatasin-III is carried by runoff into streams and lakes during the snowmelt period and whether it is also potentially hazardous to aquatic fauna. Sampling of water from streams and a lake for which the surrounding terrestrial vegetation is dominated by E. hermaphroditum was done during the snowmelt period in May 1993 and in 1998, and analyzed for batatasin-III. Using 24- and 48-hr standard toxicity tests, we analyzed toxicity to brown trout (Salmo trutta) alevins and juvenile water fleas (Daphnia magna). Toxicity (proportion of dead individuals) to trout was tested at pH 6.5 and compared with that of a phenol within a range of ...
Rice University team develops nano drills to kill worms and water fleas by infiltrating cells - small tech news
James Tour, lead researcher on the study, said: This work shows that whole organisms, such as small worms and water fleas, can be killed by nanomachines that get into them. This is not only single-cell death, but also the entire organism, which causes thousands of cells to die. . In a subsequent test, the researchers shifted the target to a larger animal, the mouse. They smeared a local mixture containing micromachines on the skin of mice, and once activated, the drill bits caused skin damage and ulcers. While this doesnt sound good for poor animals, the researchers say the test shows how nanodrills will eventually be used in beneficial ways. They can be used on human skin to penetrate melanoma, kill parasites such as worms or fight eczema and other skin diseases.. The idea is that nanodrills can be trained to target only certain cells so that they dont harm healthy human cells.. The study was published in the journal ACS Applied Materials and Interfaces.. ...
Worms, water fleas and bacteria could bring clean water to remote areas | Science Features | Naked Scientists
Earthworms and tiny water fleas could help deliver clean water to billions of people in remote areas of the world by eating up sewage and other pollution.
Fresh water flea panic - so it must be happening in the oceans too | Watts Up With That?
From York University - quite possibly the most poorly written science by press release Ive seen this year. The leaps of may are profound, and the footbal team analogy is designed to elicit sympathy. I suppose if Daphnia populations were collapsing in lakes due to lack of helmets and shoulder pads, wed see a collapse…
We show that the stable (C, N, O) isotopic composition of the water flea Daphnia pulicaria is strongly related to that of its diet (C, N) and the water they live in (O). We also show that the stable isotopic composition of the sheaths of Daphnia resting eggs (ephippia) is indicative of the isotopic composition of Daphnia that produced them. This implies that stable isotope ratios of fossil Daphnia ephippia can provide information on past ecological and climatic developments in and around lakes ...
Resources, key traits and the size of fungal epidemics in Daphnia populations. | Sigma-Aldrich
Sigma-Aldrich offers abstracts and full-text articles by [David J Civitello, Rachel M Penczykowski, Aimee N Smith, Marta S Shocket, Meghan A Duffy, Spencer R Hall].
DNA transposon dynamics in populations of Daphnia pulex with and without sex | Proceedings of the Royal Society of London B:...
The dual role of recombination in TE proliferation has generated great interest in the effects of sexual versus asexual reproduction on TE loads in the genome over time (Arkhipova & Meselson 2000; Wright & Finnegan 2001; Dolgin & Charlesworth 2006). Sex can facilitate the spread of a new TE throughout a population, but it also provides a mechanism through which new copies can be lost. Thus, sex can lead to an accelerated rate of increase and decrease in TEs over time relative to asexuals, and also impact the distribution of TEs among individuals within a population where sex has been lost (Schaack et al. in press). We surveyed six families of transposable elements in populations of D. pulex, which reproduce either with or without sex and find that both the number and distribution of TEs differ between cyclical parthenogens and obligate asexuals, despite the fact that obligately asexual populations in this species are thought to be relatively young (Lynch et al. 2008). Even though purging ...
NMDA receptor activation upstream of methyl farnesoate signaling for short day-induced male offspring production in the water...
Background The cladoceran crustacean Daphnia pulexproduces female offspring by parthenogenesis under favorable conditions, but in response to various unfavorable external stimuli, it produces male...
Nucleotide Polymorphism and Within-Gene Recombination in Daphnia magna and D. pulex, Two Cyclical Parthenogens | Genetics
THE efficacy of natural selection may be severely reduced in asexual compared to sexual organisms due to the absence of recombination and segregation (Fisher 1930; Barton and Charlesworth 1998; Otto and Lenormand 2002; Agrawal 2006). Consequently, asexual populations may adapt more slowly to changing environments (Peck 1994; Orr 2000; Roze and Barton 2006) and suffer from an increased genetic load (Muller 1964; Crow and Kimura 1970; Pamilo et al. 1987; Kondrashov 1988; Charlesworth 1994). Both of these factors may contribute to the rarity of obligate asexuality in eukaryotes (Bell 1982), despite its immediate advantages over sexual reproduction (Maynard Smith 1978). The main reason for the decreased efficiency of selection in asexual organisms is that due to the complete linkage of their genomes, selection cannot operate on different mutations independently (the Hill-Robertson effect, Hill and Robertson 1966). Thus, deleterious mutations anywhere in the genome reduce the effective population ...
Essential oil of Cedarwood Texas obtained from... - Registration Dossier - ECHA
This study was performed to assess the acute toxicity of Cedrol, Cedarwood Texas oil distilled on Daphnia magna, and was conducted in accordance with OECD Guideline for Testing of Chemicals No. 202. A full test was performed based on the results of a preceding range-finding test. Water Accommodated Fractions (WAFs) of Cedrol, Cedarwood Texas oil distilled were prepared and used as test concentrations. Twenty daphnids per group (5 per replicate, quadruplicate) were exposed to an untreated control and to WAFs prepared at loading rates of 10, 18, 32, 56 and 100 mg/L under static conditions. The total exposure period was 48 hours and samples for Total Organic Carbon (TOC) analyses were taken at the start and at the end of the test. Due to the potential volatile nature of the test item, the exposure was performed in airtight closed vessels with headspace reduced to minimum. The measured TOC concentrations increased with the loading rate at the three lowest loading rates the start. At the higher ...
[email protected] - Symposium Of University Research and Creative Expression (SOURCE): UV-induced DNA damage in Daphnia magna...
Every day we are exposed to carcinogens, including ultraviolet radiation (UVR). High levels of ultraviolet radiation are known to cause DNA damage. One of the most common forms of UVR-induced damage, the pyrimidine dimer, is repaired by an enzymatic reaction powered by visible light. We wanted to find out if there is variation in the level of UVR-induced DNA damage induced in two different clones of Daphnia magna, a model organism for ecotoxicology. One clone was derived from a mid-latitude deep reservoir, where escape from UVR is possible via vertical migration. The second clone was from a high-latitude shallow rock pool, where D. magna are exposed to high levels of UVR. Pregnant mothers from each clone line were subjected to ecologically relevant levels of UVR in the lab. Immediately afterwards, we extracted the embryos, suspended the cells in agarose, and performed a comet assay, which allows for quantification of DNA damage within individual cells. The slides were viewed under a fluorescent
Daphnia magna Reproduction (OECD 211) | Chemex
The primary objective of the test is to assess the effect of chemicals on the rate of reproduction of Daphnia magna. The concentrations used in the study are based on the results of an acute immobilisation test. The duration of the study is 21 days and the number of offspring produced, together with adult and juvenile survival, is reported. A semi-static system is recommended and the frequency of test media renewal depends on the stability of the substance. The study is started with juveniles which are female and start to produce live young by parthenogenesis after about 7 days.. Juvenile production is compared to that of the controls to determine the lowest observed effect concentration (LOEC) and the no effect concentration (NOEC) in addition of the EC50. Other adverse effects are recorded such as abnormal development of juveniles in the brood pouch (white eggs). Shedding of un-hatched eggs, presence of male Daphnia, ephippial eggs and differences in the size of adults at the end of the test ...
Strong intraspecific variation in genetic diversity and genetic differentiation in Daphnia magna: the effects of population...
WALSER, B. and HAAG, C. R. (2012), Strong intraspecific variation in genetic diversity and genetic differentiation in Daphnia magna: the effects of population turnover and population size. Molecular Ecology, 21: 851-861. doi: 10.1111/j.1365-294X.2011.05416.x ...
Daphnia magna negatively affected by chronic exposure to purified Cry-toxins
Cry-toxin genes originating from Bacillus thuringiensis are inserted into genetically modified (GM) plants, often called Bt-plants, to provide insect resistance to pests. Significant amounts of Bt-plant residues, and thus Cry-toxins, will be shed to soil and aquatic environments. We exposed Daphnia magna to purified Cry1Ab and Cry2Aa toxins for the full life-span of the animals. We used single toxins in different doses and combinations of toxins and Roundup, another potential stressor on the rise in agricultural ecosystems. Animals exposed to 4.5 mg/L (ppm) of Cry1Ab, Cry2Aa and the combination of both showed markedly higher mortality, smaller body size and very low juvenile production compared to controls. Animals exposed to 0.75 mg/L also showed a tendency towards increased mortality but with increased early fecundity compared to the controls. Roundup stimulated animals to strong early reproductive output at the cost of later rapid mortality. We conclude that i) purified Cry-toxins in high ...
Comparative studies on effects of predation by fish on Daphnia in Lake Donghu (China) and Loch Leven (Scotland) - NERC Open...
Yang, Y.; May, L.; Gunn, I.D.M.; Huang, X.; Liu, J.. 1999 Comparative studies on effects of predation by fish on Daphnia in Lake Donghu (China) and Loch Leven (Scotland). In: Ecosystem Approaches for Fisheries Management. American Fisheries Society, 265-281. (Alaska Sea Grant Report, 1). Full text not available from this repository. (Request a copy ...
Stress signaling: coregulation of hemoglobin and male sex determination through a terpenoid signaling pathway in a crustacean |...
Zeis et al. (2004) recently reported that hemoglobin concentration in daphnids increased with increasing temperature. Mitchell (2001) noted a low incidence of sexually ambiguous offspring when daphnids were reared at 30°C. Elevated temperature may prove to be an environmental signal that stimulates both hemoglobin induction and male sex determination through the common signaling pathway. Preliminary experiments in our laboratory support this premise. However, elevated temperature may stimulate different signaling pathways, resulting in multiple outcomes. For example, oxygen saturation decreases with increasing water temperature, which may stimulate hemoglobin production via the hypoxia signaling pathway. Increased temperature may also adversely impact the uptake or assimilation of nutrients resulting in male production via the terpenoid signaling pathway.. The minimum components to the putative terpenoid signaling pathway described in this study would consist of the hormone (i.e. methyl ...
Annotation, phylogenetics, and expression of the nuclear receptors in Daphnia pulex
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
DiVA - Sökresultat
The last ten years have witnessed increasing interest in host-pathogen interactions involving invertebrate hosts. The invertebrate innate immune system is now relatively well characterised, but in a limited range of genetic model organisms and under a limited number of conditions. Immune systems have been little studied under real-world scenarios of environmental variation and parasitism. Thus, we have investigated expression of candidate innate immune system genes in the water flea Daphnia, a model organism for ecological genetics, and whose capacity for clonal reproduction facilitates an exceptionally rigorous control of exposure dose or the study of responses at many time points. A unique characteristic of the particular Daphnia clones and pathogen strain combinations used presently is that they have been shown to be involved in specific host-pathogen coevolutionary interactions in the wild. We choose five genes, which are strong candidates to be involved in Daphnia-pathogen interactions, ...
Daphnia - Wikipedia
Daphnia species are normally r-selected, meaning that they invest in early reproduction and so have short lifespans. An individual Daphnia life-span depends on factors such as temperature and the abundance of predators, but can be 13-14 months in some cold, oligotrophic fish-free lakes. In typical conditions, however, the life cycle is much shorter, not usually exceeding 5-6 months.. Daphnia are typically filter feeders, ingesting mainly unicellular algae and various sorts of organic detritus including protists and bacteria Beating of the legs produces a constant current through the carapace which brings such material into the digestive tract. The trapped food particles are formed into a food bolus which then moves down the digestive tract until voided through the anus located on the ventral surface of the terminal appendage. The second and third pair of legs are used in the organisms filter feeding, ensuring large unabsorbable particles are kept out, while the other sets of ...
Frontiers | Dynamic Responses of Phosphorus Metabolism to Acute and Chronic Dietary Phosphorus-Limitation in Daphnia |...
Food quality is highly dynamic within lake ecosystems and varies spatially and temporally over the growing season. Consumers may need to continuously adjust their metabolism in response to this variation in dietary nutrient content. However, the rate of metabolic responses to changes in food nutrient content has received little direct study. Here, we examine responses in two metabolic phosphorus (P) pools, ribonucleic acids (RNA), and adenosine triphosphate (ATP) along with body mass and body P content in Daphnia magna exposed to chronic and acute dietary P-limitation. First, we examined food quality effects on animals consuming different food carbon (C):P quality over a 14 day period. Then, we raised daphnids on one food quality for 4 days, switched them to contrasting dietary treatments, and measured changes in their metabolic responses at shorter time-scales (over 48 h). Animal P, RNA, and ATP content all changed through ontogeny with adults containing relatively less of these pools with increasing
Amy Brown Science: February 2015
Daphnia are tiny crustaceans, closely related to a shrimp. They are often called water fleas. They are small, but not microscopic. They can be seen with the naked eye, but you will need a dissecting microscope to view the beating heart. Daphnia can be purchased from any of the companies that sell lab supplies and equipment. Since Daphnia are arthropods, they demonstrate the three major arthropod characteristics: exoskeleton, jointed appendages, and segmented body. The exoskeleton is clear, allowing the student to easily view the heart. Daphnia are ectotherms and their body temperature changes with the surrounding environment. This further means that there is a direct relationship between the internal body activities and the external temperature of the water in which it lives ...
Exotic Aquatic Invertebrates in Illinois - Education
The spiny water flea lives in Lake Michigan and possibly some inland lakes. It uses swimming antennae to move in the water. As it grows, it sheds the outer shell over its body, but not over its spine. The barbed tail spine makes it difficult for predators to swallow this organism, and, after attempting to eat it, they often spit it back out. The life span of the spiny water flea lasts several days to about two weeks. Adults are present in water bodies from late spring until fall. This crustacean may produce up to 10 offspring every two weeks. Most of the spring, summer and fall populations are comprised of females. These adult females produce unfertilized eggs that develop into female offspring that are identical to the mother. This cycle continues as long as the water temperature is not too hot or too cold and food is plentiful. When the water temperature begins to cool in the fall, both males and females are produced, allowing sexual reproduction to occur. Eggs are then deposited over the ...
Reaction mass of Amines, C10-14-branched and... - Registration Dossier - ECHA
Experimental data on the acute toxicity of the Orasol Black X51 (ES 939-191-9) to aquatic invertebrates are available from a static limit test on Daphnia magna conducted according to OECD 202. No mortality was observed at a test concentration of 100 mg/L after 48 h (BASF SE, Rep. no.: 17F0074/16E023, 2017). Therefore, the 48h- EC50 is higher than 100 mg/L. It can be concluded, that Orasol Black X51 is with high probability acutely not harmful to aquatic invertebrates. ...
Water flea has most complex genome - Independent.ie
IT is a question worthy of the scientists of CSI Miami -- which has the more complex gene structure a human being or the humble flea?
Water flea | place
Confocal microscopic image captured through the Keith Porter Image Facility, UMBC, a collaborative project between Stephen Bradley & Dr. Tagide deCarvalho, UMBC. The process is called autofluorescence a natural emission of light by biological structures such as mitochondria and lysosomes when they have absorbed light, and is used to distinguish the light originating from artificially added fluorescent markers (fluorophores). The bug was sampled from Masonville Cove Environmental Education Center, next to Brooklyn & Curtis Bay, Maryland, August 2017. The overall project is called Waters Edge, Biome Tells, funded by a UMBC summer research fund.. ...
Target gene approaches: Gene expression in Daphnia magna exposed to predator-borne kairomones or to microcystin-producing and...
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
Study of environmental risks incurred by leakage of lithium cells to the food chain in a freshwater ecosystem on Environmental...
Monitor The Environment Through Gene Expression : TreeHugger
The water flea, Daphnia magna, is the canary of environmental toxicology. Scientists have found the flea to be sensitive to a wide array of toxic conditions. Unlike a mine, a river can contain multiple toxins, and a wide range of reasons why a
Daphnia magna (large species) Daphnia pulex (small, most common) Daphnia longispina Moina (smallest) Crustaceans portal N.N. ... Daphnia Daphnia lumholtzi (invasive species) Cercopagis pengoi (invasive species) Bythotrephes longimanus (invasive species) ... Dieter Ebert (2005). "Introduction to Daphnia biology". Ecology, Epidemiology, and Evolution of Parasitism in Daphnia. Bethesda ... Lampert, W. (2011). Daphnia: development of a model organism in ecology and evolution. Oldendorf/Luhe: Internat. Ecology Inst. ...
... like Daphnia); and flake foods. At best they are kept as a group of three or four. These fish are peaceful community fish. The ...
Ecological light pollution
Zooplankton (e.g. Daphnia) exhibit diel vertical migration. That is, they actively change their vertical position inside of ... "Urban light pollution alters the diel vertical migration of Daphnia" (PDF). Verh. Internat. Verein. Limnol. 27: 1-4. Falchi, F ...
List of sequenced animal genomes
"Daphnia pulex v1.0". DOE Joint Genome Institute. Retrieved 2009-11-29.. *^ Colbourne JK, Pfrender ME, Gilbert D, Thomas WK, ... "The Daphnia Genomics Consortium". Archived from the original on 9 January 2010.. ... "The ecoresponsive genome of Daphnia pulex". Science. 331 (6017): 555-61. Bibcode:2011Sci...331..555C. doi:10.1126/science. ...
It is an obligatory gut parasite with the crustacean Daphnia magna as its only host. So far it has been reported from Europe ... The O. colligata genome has acquired these genes from its Daphnia host by horizontal gene transfer. It is suggested, that the ... In comparison with other endoparasites of Daphnia, O. colligata is rather avirulent and does not drive infected host ... Ebert, Dieter (2005-01-01). "Chapter 3, Some parasites of Daphnia". Ecology, Epidemiology, and Evolution of Parasitism in ...
In Daphnia, P. ramosa induces gigantism. P. penetrans parasitized females of the nematode Meloidogyne javanica, on the other ... The described species and their hosts include: P. ramosa: parasite of Cladocerans, including Daphnia. P. nishizawae: parasite ... Ebert, D. (2005). Ecology, epidemiology and evolution of parasitism in Daphnia. National Library of Medicine (US), National ...
Generic Model Organism Database
2005). "wFleaBase: the Daphnia genome database". BMC Bioinformatics. 6: 45. doi:10.1186/1471-2105-6-45. PMC 555599 . PMID ...
Daphnia pulex) Chelicerata • Black-legged tick (Ixodes scapularis) Nematoda • Roundworm (Caenorhabditis elegans) • Large ...
... larval survival and growth Daphnia, Daphnia magna, 21-d survival and reproduction Green algae, Raphidocelis subcapitata, 72-h ... Daphnia magna''), and freshwater algae (e.g. ''Raphidocelis subcapitata'') The probable effects concentration (PEC), the ...
In response, some species, especially Daphnia sp., make daily vertical migrations in the water column by passively sinking to ...
nov., isolated from Daphnia cucullata (Crustacea: Cladocera)". International Journal of Systematic and Evolutionary ... daphniae is a gram-positive bacterium from the genus Nocardioides that has been isolated from the water flea Daphnia cucullata ...
Michael Lynch (geneticist)
This species of Daphnia's asexual lineage is rather young in an evolutionary time perspective and rapidly go extinct. It is ... Study of Daphnia pulex, a microcrustacean that has the ability to reproduce sexually and asexually based upon which is ... deleterious newly arisen introns in species of Daphnia, genomic response to alterations in population size and mutation rates ... "Insertion Polymorphisms of Mobile Genetic Elements in Sexual and Asexual Populations of Daphnia pulex". Genome Biology and ...
The crustacean Daphnia and its numerous parasites have become one of the main model systems for studying coevolution. The host ... Decades of coevolution between Daphnia magna and the bacterium Pasteuria ramosa have been reconstructed, reanimating resting ... Ebert, D. (2008). "Host-parasite coevolution: Insights from the Daphnia-parasite model system". Current Opinion in Microbiology ... Model systems include the nematode Caenorhabditis elegans with the bacterium Bacillus thuringiensis; the crustacean Daphnia and ...
It is a common predator of Daphnia pulex. "Lepidurus arcticus". Integrated Taxonomic Information System. Retrieved May 28, 2013 ... 2004 ISBN 0-7876-5362-4. "Species Descriptions by Chip Hannum". Kirsten Christoffersen (2001). "Predation on Daphnia pulex by ...
水蚤 - 維基百科，自由的百科全書
亞屬 Daphnia. Daphnia ambigua. Daphnia arenata. Daphnia catawba. Daphnia cheraphila. Daphnia latispina. Daphnia melanica. Daphnia ... Daphnia minnehaha. Daphnia neo-obtusa. Daphnia obtusa. Daphnia oregonensis. Daphnia parvula. Daphnia pileata. Daphnia prolata. ... Daphnia lacustris. Daphnia laevis. Daphnia longiremis. Daphnia longispina. Daphnia mendotae. Daphnia thorata. Daphnia umbra. *亞 ... Daphnia barbata. Daphnia brooksi. Daphnia ephemeralis. Daphnia exilis. Daphnia lumholtzi. Daphnia magna. Daphnia salina. ...
Infection of Daphnia populations by Hamiltosporidium have been recorded in the United Kingdom, Russia, Belgium and Israel (H. ... Both species infect only the crustacean Daphnia magna (Waterflea). D. magna and H. tvaerminnensis are a frequently used model ... The unicellular parasites infect the crustacean Daphnia magna. Both species H. magnivora and H. tvaerminnensis infect the fat ... Mangin, K. L.; M. Lipsitch & D. Ebert (1995). "Virulence and transmission modes of two microsporidia in Daphnia magna". ...
ISBN 978-0-471-35837-4. Ellen Decaestecker, Luc De Meester & Joachim Mergaey (2009). "Cyclical parthenogeness in Daphnia: ...
Threshold host density
8: Epidemiology". Ecology, Epidemiology, and Evolution of Parasitism in Daphnia. Bethesda MD: National Center for Biotechnology ...
permanent dead link] "Daphnids: Ceriodaphnia dubia, Daphnia magna". Marinco Bioassay Laboratory, Inc. 2005. Donald E. Francisco ... as they seems to be more sensitive than other cladocerans as Daphnia pulex - pulicaria. S. J. Brands. "Ceriodaphnia dubia - ...
The genus Daphnia alone contains around 150 species. These families are recognised: Order Cladocera Latreille, 1829 Suborder ... ISBN 978-0-520-23939-5. Ellen Decaestecker; Luc De Meester; Joachim Mergaey (2009). "Cyclical parthenogeness in Daphnia: sexual ... Daphnia lumholtzi (invasive species) Moina (smallest) Zooplankton L. Forró; N. M. Korovchinsky; A. A. Kotov; A. Petrusek (2008 ...
Paradox of enrichment
An example is of Daphnia and fish predators. Autotoxins and other predator density-dependent effects: if predator density ...
Daphnia is eaten when other foods are unavailable. Seahorses spend most of their time anchoring to coral reefs and branches ...
Larger zooplankton include water fleas (Bosmina) and copepods (Daphnia); and smaller species, rotifers, seem to have increased ...
Drosophila C virus
doi:10.6084/m9.figshare.1297064 Chadwick, W; Little, T. J. (2005). "A parasite-mediated life-history shift in Daphnia magna". ...
Daphnia, a crustacean, swims by beating its antennae instead. There are also a number of forms of swimming molluscs. Many free- ...
This form of automixis has been observed in the water flea Daphnia magna and the Colombian rainbow boa constrictor Epicrates ... "Uncovering cryptic asexuality in Daphnia magna by RAD sequencing". Genetics. 201 (3): 1143-55. doi:10.1534/genetics.115.179879 ...
For example, water fleas (Daphnia magna), exposed to microsporidian parasites produce more offspring in the early stages of ... Chadwick W, Little TJ (March 2005). "A parasite-mediated life-history shift in Daphnia magna". Proceedings: Biological Sciences ...
Reduced fitness of Daphnia magna fed a Bt-transgenic maize variety. - Archives of Environmental Contamination and Toxicology 55 ... Demographic responses of Daphnia magna fed transgenic Bt-maize. - Ecotoxicology DOI 10.1007/s10646-009-0427-x. (Open Access).: ... paper: i) important claims about the Daphnia magna study are incorrect (that the amount of toxin in the experiment was not ...
A recent example showed 6 micromolar killing 93% of all Daphnia in water. The free zinc ion is a powerful Lewis acid up to the ... "Mechanisms of chronic waterborne Zn toxicity in Daphnia magna". Aquatic Toxicology. 77 (4): 393-401. doi:10.1016/j.aquatox. ...
Daphnia - Wikipedia
The following are listed as vulnerable by IUCN: Daphnia nivalis, Daphnia coronata, Daphnia occidentalis, and Daphnia jollyi. ... Daphnia and Moina Data related to Daphnia at Wikispecies Daphnia Genomics Consortium Daphnia Images and Information at MBL ... Daphnia, a genus of small planktonic crustaceans, are 0.2-5 millimetres (0.01-0.20 in) in length. Daphnia are members of the ... Anatomy of Daphnia Daphnia species are normally r-selected, meaning that they invest in early reproduction and so have short ...
Daphnia sinevi - Wikipedia
Daphnia sinevi is a species of water fleas from the Russian Far East. Daphnia sinevi grows to a length of 1.73 millimetres ( ... The closest relatives of D. sinevi are other species in the species group around D. curvirostris, especially Daphnia morsei. ... Alexey A. Kotov, Seiji Ishida & Derek J. Taylor (2006). "A new species in the Daphnia curvirostris (Crustacea: Cladocera) ... 0.068 in). Daphnia sinevi is only known from a single pool, 10 metres (33 ft) in diameter at Avangard, near Nakhodka, Primorsky ...
Ameiotic recombination in asexual lineages of Daphnia | PNAS
Daphnia Mutation-Accumulation Line Maintenance.. Single female individuals of Daphnia pulex (designated LIN and OL3) and D. ... Daphnia pulex and Daphnia obtusa. The MA individuals derived from D. pulex were determined to be obligately asexual, whereas D ... Ameiotic recombination in asexual lineages of Daphnia. Angela R. Omilian, Melania E. A. Cristescu, Jeffry L. Dudycha, Michael ... Ameiotic recombination in asexual lineages of Daphnia. Angela R. Omilian, Melania E. A. Cristescu, Jeffry L. Dudycha, Michael ...
The Daphnia bioassay: a critique | SpringerLink
Daphnia magnais used widely as a standard ecotoxicological indicator organism, and protocols exist for its use in assessing the ... Daphnia magna as a test animal in acute and chronic toxicity tests. Hydrobiol. 59: 125-134.Google Scholar ... Daphnia bioassay effects of food concentration genetic variation maternal effects laboratory culture genotype-environment ... Daphnia magna is used widely as a standard ecotoxicological indicator organism, and protocols exist for its use in assessing ...
Population Genomics of Daphnia pulex | Genetics
Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ... Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ... Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ... Using data from 83 isolates from a single population, the population genomics of the microcrustacean Daphnia pulex are ...
Population Genomics of Daphnia pulex | Genetics
Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ... Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ... Population Genomics of Daphnia pulex. Michael Lynch, Ryan Gutenkunst, Matthew Ackerman, Ken Spitze, Zhiqiang Ye, Takahiro ...
Daphnia - Wikipedia
The following are listed as vulnerable by IUCN: Daphnia nivalis, Daphnia coronata, Daphnia occidentalis, and Daphnia jollyi. ... USGS: Nonindigenous Aquatic Species: Daphnia lumholtzi *^ Center for Freshwater Biology - University of New Hampshire: Daphnia ... Daphnia, a genus of small planktonic crustaceans, are 0.2-5 millimetres (0.01-0.20 in) in length. Daphnia are members of the ... Dieter Ebert (2005). "Introduction to Daphnia biology". Ecology, Epidemiology, and Evolution of Parasitism in Daphnia. Bethesda ...
Environmental Effects of Industrial Run-off on Daphnia magna
The Daphnia magna were allowed to reproduce, and their offspring were then used in the experiments. The Daphnia magna were fed ... Every other day I documented the Daphnia magnas heart rate and eye reflex, and also fed the Daphnia magna with the liquid ... Every week I fed the Daphnia magna the liquid invertebrate food. I continued this experiment until all of the Daphnia magna had ... Before conducting any experiments using Daphnia magna, age controls were set. This was to ensure that the Daphnia magna were ...
Investigating the Effects of Water Pollution on Daphnia magna
Shes continuing to investigate the mysterious growths that have formed on her Daphnia magna. ... I was taking the heart rate of all of the Daphnia. I had just put one urea-exposed Daphnia on a slide. I slipped it under the ... This was to see how the two different pond waters affected the Daphnia. I found through this study that the Daphnia population ... Before I knew it, I was ordering my new best friends, Daphnia magna. Daphnia magna are small invertebrate crustaceans, the size ...
Re: How does a Daphnia absorb Ethanol
is the daphnia heart neurogenic or myogenic?
Subject: is the daphnia heart neurogenic or myogenic?. Date: Fri Feb 20 00:30:24 2009. Posted by Luck. Grade level: undergrad ... Re: is the daphnia heart neurogenic or myogenic? Current Queue , Current Queue for General Biology , General Biology archives ... i have come across articles saying that daphnia posess no cardiac gangalion and therefore resemble myogenic hearts of the ...
Daphnia Culture Kits | Carolina.com
Each kit contains a 1-1/2-gal plastic aquarium with lid, food source, living starter culture of Daphnia, and instructions. ... Establish and maintain a culture of Daphnia magna or Daphnia pulex with your choice of Daphnia culture kit. ... Establish and maintain a culture of Daphnia magna or Daphnia pulex with your choice of Daphnia culture kit. Each kit contains a ... Establish and maintain a culture of Daphnia magna or Daphnia pulex with your choice of Daphnia culture kit. ...
O-mannosyl-transferase - Daphnia magna
Daphnia pulex - Wikipedia
"Daphnia pulex". Animal Diversity Web. University of Michigan.. *^ "Daphnia pulex". An Image-Based Key To The Zooplankton Of The ... "Daphnia pulex". An Image-Based Key To The Zooplankton Of The Northeast (USA). Version 4.0. University of New Hampshire. ... regulates Daphnia relationships to predators. Daphnia pulex in particular has been an important model species for investigating ... "Daphnia pulex v1.0". DOE Joint Genome Institute. Retrieved 2009-11-29.. *^ Florian Odronitz; Sebastian Becker; Martin Kollmar ( ...
Summarry of responses on Daphnia. by () *Summarry of responses on Daphnia. by () *Daphnia food. by DougGuynn/aol.com (Sun, 31 ... Daphnia again. by spush/saudan.HAC.COM (Fri, 28 Feb 1997) *how to catch daphnia. by Foo ,foo/usa.net, (Sun, 30 Mar 1997) *RE: ... Daphnia culture. by jvonich-at-aol.com (JVonich) (20 Mar 1995) *Daphnia FAQ. by qx01820-at-inet.d48.lilly.com (14 Apr 95) * ... Growing Daphnia & more on worms. by Biplane10/aol.com Date: Sat, 17 Jun 2000. An update on the daphnia tank. It was reported ...
... are small, planktonic crustaceans. Provides a classic study in arthropod behavior and anatomy. Examines the eye, brain ... Identifies two kinds of eggs: those that hatch directly into female daphnia and resistant eggs that carry the species through ... Daphnia are small, planktonic crustaceans. Provides a classic study in arthropod behavior and anatomy. Examines the eye, brain ... Identifies two kinds of eggs: those that hatch directly into female daphnia and resistant eggs that carry the species through ...
Sucralose induces biochemical responses in Daphnia magna
Spectral SAR Ecotoxicology of Ionic Liquids: The Daphnia magna Case
Spectral SAR Ecotoxicology of Ionic Liquids: The Daphnia magna Case. Mihai V. Putz,1 Ana-Maria Lacrama,1,2 and Vasile Ostafe1 ... International Organisation for Standardisation, 1982, Water Quality Determination of the Inhibition of the Mobility of Daphnia ... C2: Acute Toxicity for Daphnia. J.O. No. 154, 5/6/1992. ... chronic toxicity of imidazolium-based ionic liquids on Daphnia ...
Daphnia Heart Rate Experiment - 1589 Words | Education Index
... the affect of Caffeine on Daphnias heartbeat Introduction: Aim: The aim of this experiment is to understand the affect of the ... daphnia (and daphnia tank). • Tank of fresh pond water. • Microscope. • Cavity slides. • 1ml pipette. • 1ml syringe. • 10ml ... Place one daphnia onto a cavity slide and place under microscope. Allow the daphnia to adjust for a minute or two.. • Using the ... Daphnia -. Daphnia (water fleas) are grouped as crustaceans under the arthropod group of Kingdom Anamalia. They have an open ...
Bioaccumulation and oxidative stress in Daphnia magna exposed to ...
Article Bioaccumulation and oxidative stress in Daphnia magna exposed to arsenite and arsenate. Arsenic pollution and its ... No comments were found for Bioaccumulation and oxidative stress in Daphnia magna exposed to arsenite and arsenate. Be the first ... Bioaccumulation and oxidative stress in Daphnia magna exposed to arsenite and arsenate 0 ... Daphnia magna, induced by 2 inorganic arsenic species (As(III) and As(V)). The bioaccumulation of arsenic, Na+/K+-adenosine ...
Characterization of key bacterial species in the Daphnia magna microbiota using shotgun metagenomics | Scientific Reports
We assembled five potentially novel metagenome-assembled genomes (MAGs) of core bacteria in Daphnia magna. Genes involved in ... we combined 16S rRNA sequencing and shotgun metagenomics to characterize the whole-organism microbiota of Daphnia magna. ... The keystone zooplankton Daphnia magna has recently been used as a model system for understanding host-microbiota interactions ... Daphnia are colonized with bacteria throughout their entire body cavity and gut7,8. Composition of the Daphnia microbiota ...
Some Parasites of Daphnia - Ecology, Epidemiology, and Evolution of Parasitism in Daphnia - NCBI Bookshelf
I give a brief introduction to some endoparasite species of Daphnia. Three bacteria, one fungus, four microsporidia, and one ... Chapter 3Some Parasites of Daphnia. In this chapter, I give a brief introduction to some endoparasite species of Daphnia. Three ... Some Parasites of Daphnia - Ecology, Epidemiology, and Evolution of Parasitism i.... Some Parasites of Daphnia - Ecology, ... a microsporidian parasite of Daphnia magna and Daphnia pulex, with establishment of the genus Glugoides (Microspora, Glugeidae ...
Heart Rate of Daphnia Essay
Information Background Daphnia are small water fleas a type of ... Heart rate of Daphnia Aim Investigating the effect of caffeine ... Heart rate of Daphnia. Aim. Investigating the effect of caffeine on the heart rate of Daphnia.. Information/Background. Daphnia ... I predict the more caffeine which the daphnia is exposed to increases the heart rate; the more caffeine that the daphnia ... Daphnia. Light microscope. Pipette. Glass slide. Beaker (100ml). Stop clock. Lab book. Safety;. -Ensure the wire of the ...
Daphnia sp., Culture, Class Size 30
Daphnia is also a popular food organism for Hydra and other invertebrates. ... Daphnia, the water-flea, has long been popular for simple physiology studies because its heartbeat is easily viewed under the ... Daphnia Culture Kit. Daphnia magna. Daphnia magna. Daphnia sp.. Daphnia sp.. Package Size. Class Size 30. Class Size 30. Class ... Daphnia also eat yeast from suspension-prepare by adding a pinch of active dry yeast to 100 mL of warm water and let stand 2-3 ...
Glyphosate-Residues in Roundup-Ready Soybean Impair Daphnia magna Life-Cycle
Bøhn, T., Primicerio, R., Hessen, D.O. and Traavik, T. (2008) Reduced Fitness of Daphnia magna Fed a Bt-Trans- genic ... Bøhn, T., Traavik, T. and Primicerio, R. (2010) Demographic Responses of Daphnia magna Fed Transgenic Bt-Maize. ... OECD (2008) OECD-211 Guidelines for Testing of Chemicals: Daphnia magna Reproduction Test. OECD, Geneva. ... Glyphosate-Residues in Roundup-Ready Soybean Impair Daphnia magna Life-Cycle. Journal of Agricultural Chemistry and Environment ...
Toxicity of new generation flame retardants to Daphnia magna
... Journal. Science of the Total Environment. Volume. 463-464. Pages ... Therefore, in the present study the toxicity of a wide range of HFFRs to the water flea Daphnia magna was investigated. Our ...
Bio-Pure Frozen Daphnia - Aquarium Equipment Reviews
NANFA Mailing List Archive: NANFA-- Re Daphnia
Previous message: Mark: "Re: NANFA-- daphnia" Aloha everyone,. I work with Moina and Daphnia magna. The Moina tend to ... They hadnt but the tank is chock full of daphnia. Two weeks ago, this. , tank was totally empty and very clean.. ,. , I would ... Subject: NANFA-- daphnia. ,. , Im starting to believe in spontaneous generation.. ,. , A couple of weeks ago, I brought a 55 ... NANFA-- Re Daphnia. Mach Fukada (fukada-in-aloha.net). Sat, 5 Jun 2004 09:04:33 -1000 * Messages sorted by: [ date ][ thread ] ...
Development of an RNA interference method in the cladoceran crustacean Daphnia magna
Daphnia Reproduction test | Water | Chemistry
Daphnia Reproduction test - Free download as PDF File (.pdf), Text File (.txt) or read online for free. sử dụng daphnia magna ... Put 1 daphnia per 50 ml of solution into test vessels. Follow the instructions of the assistant and put either 1 daphnia into ... Daphnia (Daphnia magna) Offspring number per one adult Stable temperature and light cycle 16 h/8 h (light/dark), feeding 4 ... Young female Daphnia, aged up to 24 hours are exposed to the test sample at a range of concentrations during 21 days. At the ...
PulexSpeciesCrustaceansZooplanktonToxicityCladoceraFleasPopulationsMagna exposedInvertebratesAlgaeOrganismOrganismsExposureLive DaphniaCrustaceaGenusSkipCrustacean Daphnia magnaMicroscopeGenesWaterAsexualEcologicalGrowth and fecundityTaxaGenomicCaulleryaResponsesEggsParthenogeneticBacteriaLongispinaTemperatureMosquito larvaeGenotypesPondMoinaMaintain DaphniaConcentrationsMesniliGene expressionCarbon nanotubesEnvironmentsDraft genomePhenotypic plasticityLarvaeSpecificity
- The two most readily available species of Daphnia are D. pulex (small and most common) and D. magna (large). (wikipedia.org)
- Daphnia pulex and Daphnia obtusa . (pnas.org)
- Using data from 83 isolates from a single population, the population genomics of the microcrustacean Daphnia pulex are described and compared to current knowledge for the only other well-studied invertebrate, Drosophila melanogaster . (genetics.org)
- Daphnia pulex is the most common species of water flea . (wikipedia.org)
- Daphnia pulex is an arthropod whose body segments are difficult to distinguish. (wikipedia.org)
-  Like most other Daphnia species, D. pulex reproduces by cyclical parthenogenesis , alternating between sexual and asexual reproduction. (wikipedia.org)
- Daphnia pulex occurs in a wide range of aquatic habitats, although it is most closely associated with small, shaded pools. (wikipedia.org)
- Similar to some other Daphnia species, the morphology of D. pulex exhibits a plastic response to the presence of predators. (wikipedia.org)
- Daphnia pulex ecology is shaped by nutrient availability and balance , which affects traits that mediate intra- and interspecific interactions. (wikipedia.org)
- Daphnia pulex in particular has been an important model species for investigating ecological stoichiometry , demonstrating that pond shading by trees increases nutrient concentrations relative to carbon in algae , which increases D. pulex body size, and therefore competitive ability and susceptibility to predation by vertebrates. (wikipedia.org)
- Daphnia pulex was the first crustacean to have its genome sequenced. (wikipedia.org)
- Here, we present a genomewide analysis of LTR retroelements in Daphnia pulex, a cyclical parthenogen and the first crustacean for which the whole genomic sequence is available. (iu.edu)
- Shotgun ecotoxicoproteomics of Daphnia pulex: biochemical effects of the anticancer drug tamoxifen. (sigmaaldrich.com)
- The aim of this study was to analyze differences of protein expression resulting from acute (2 days) and middle-term (7 days) exposure of aquatic microcrustacean Daphnia pulex to the anticancer drug tamoxifen. (sigmaaldrich.com)
- Cyclic parthenogenesis is the ancestral mode of reproduction in the cladoceran crustacean, Daphnia pulex , but some populations have made the transition to obligate parthenogenesis and this is the only mode of reproduction known to occur in arctic populations. (wiley.com)
- The two daphnid species evaluated, Daphnia pulex and Daphnia magna , exhibited different temperature dependencies. (biologists.org)
- Daphnia pulex produced fewer males with increasing temperatures between 16 and 22°C, and D. magna exhibited the opposite trend. (biologists.org)
- The aim of this study was to identify putative nuclear receptors from the first assembled genome of a crustacean Daphnia pulex http://wFleaBase.org . (pubmedcentralcanada.ca)
- Dissolved infochemicals from the aquatic larvae of the phantom midge Chaoborus induce so-called 'neck-teeth' in the first three post-embryonic stages of Daphnia pulex . (biologists.org)
- In a target gene approach, by using three Daphnia genotypes which show a gradient of neck-teeth induction in response to equal amounts of kairomone, we report a high correlation of neck-teeth induction in Daphnia pulex and relative gene expression of two chitin deacetylases. (biologists.org)
- For Daphnia pulex , it has been shown that juveniles have a larger size at hatching when exposed to Chaoborus kairomone during embryonic development, which should be advantageous, as Chaoborus is a gape-limited predator, with a strike efficiency that is lower at larger prey sizes ( Riessen and Trevett-Smith, 2009 ). (biologists.org)
- Though thoroughly studied in D. pulex , knowledge about neckteeth in other Daphnia species is limited. (springer.com)
- The similarity of neckteeth in D. longispina and D. pulex imposes yet unresolved questions on the evolutionary origin in these distantly related Daphnia groups. (springer.com)
- Here, we focus on the comparative genomics of two cyclically parthenogenetic Daphnia pulex clones (PA42 and TCO), which come from populations differing substantially in historical N e . (g3journal.org)
- We investigate the role of recombination in transposable element (TE) proliferation in the cyclical parthenogen, Daphnia pulex . (royalsocietypublishing.org)
- We investigated the impact of recombination on TE dynamics in natural populations by surveying six families of DNA transposons among populations of Daphnia pulex , an aquatic microcrustacean. (royalsocietypublishing.org)
- The draft genome sequence for Daphnia pulex facilitates the use of candidate genes by precisely identifying orthologs to functionally characterized genes in other model species. (pubmedcentralcanada.ca)
- A three and one-half year study of spatial and temporal genetic heterogeneity in a population of the cyclically, parthenogenetic cladoceran, Daphnia pulex, inhabiting a permanent farm pond in east-central Illinois, indicated that electrophoretically distinct genotypes (clones) are frequently distributed non-randomly in the pond, both vertically and horizontally. (illinois.edu)
- Daphnia pulex populations are fixed for the S allele and inhabit temporary ponds, while D. pulicaria populations are fixed for the F allele and inhabit large stratified lakes. (biomedcentral.com)
- A strong association between Ldh genotype and habitat has been also observed in members of the Daphnia pulex species complex. (biomedcentral.com)
- Here we analyzed genome-wide temporal transcriptional patterns from Daphnia pulex collected over a 44 h time period under a 12:12 LD cycle (diel) conditions using a cosine-fitting algorithm. (biomedcentral.com)
- We studied the short- (12 h) and long-term (144 h) response of Daphnia pulex lipases to quality shifts in diets consisting of different mixtures of the green alga Scenedesmus with the cyanobacterium Synechococcus , two species with contrasting lipid compositions. (biologists.org)
- Our goal was to integrate multiple omics datasets, including gene expression, splicing, histone modification and DNA methylation data generated from genetically identical female and male Daphnia pulex under controlled laboratory settings with the aim of achieving a better understanding of the underlying epigenetic factors that may contribute to the phenotypic differences observed between the two genders. (biomedcentral.com)
- The epigenetic differences between male and female in Daphnia pulex are vast and dominated by changes that promote elevated gene expression in male Daphnia . (biomedcentral.com)
- The cosmopolitan microcrustacean Daphnia pulex provides a model system for both human health research and monitoring ecosystem integrity. (biomedcentral.com)
- Daphnia pulex are used by tropical fish keeping enthusiasts as a food source for their fish and to clear green water and debris from their tanks. (tropical-fish-keeping.com)
- Daphnia pulex are easy to culture, fast growing, super nutritious, and very popular as a live fish or Axolotl food. (tropical-fish-keeping.com)
- Daphnia pulex are smaller (.008 to .12 inch in length) versions of Daphnia magna , a larger cousin to Moina macrocopa , and the small cousin to Simocephalus vetulus . (tropical-fish-keeping.com)
- In the wild, Daphnia pulex will only live about ten to thirty days, but in a controlled, predator free environment, they can attain 10 to 20 growth periods and live up to 100 days. (tropical-fish-keeping.com)
- Daphnia pulex have a transparent, folded, shell like carapace, four to six pairs of flattened thoracic legs that are used to filter algae, bacteria, and detritus, a hook shaped intestine with two digestive cavities, and a posterior ventral opening. (tropical-fish-keeping.com)
- Male Daphnia pulex are generally smaller than females, have longer antennae, and have a modified post abdomen. (tropical-fish-keeping.com)
- Female Daphnia pulex have a brood chamber located between the body wall and top of the carapace that is used to carry their eggs and are larger than males. (tropical-fish-keeping.com)
- Daphnia pulex are prolific breeders and reproduce sexually as well as asexually in a process called parthenogenesis. (tropical-fish-keeping.com)
- Parthenogenesis occurs during more favorable conditions in the summertime when entire populations of Daphnia pulex consist almost entirely of females. (tropical-fish-keeping.com)
- Daphnia pulex can be cultured in anything that holds water and is suitable for housing fish. (tropical-fish-keeping.com)
- If you are culturing Daphnia pulex indoors, you need to keep the culture from sudden changes in temperature, provide them enough light, and enough air in the form of large bubbles to break up any surface film. (tropical-fish-keeping.com)
- Daphnia is a large genus - comprising over 200 species - belonging to the cladoceran family Daphniidae. (wikipedia.org)
- Anatomy of Daphnia Daphnia species are normally r-selected, meaning that they invest in early reproduction and so have short lifespans. (wikipedia.org)
- Most Daphnia species have a life cycle based on "cyclical parthenogenesis", alternating between parthenogenetic (asexual) reproduction and sexual reproduction. (wikipedia.org)
- Daphnia sinevi is a species of water fleas from the Russian Far East. (wikipedia.org)
- The closest relatives of D. sinevi are other species in the species group around D. curvirostris, especially Daphnia morsei. (wikipedia.org)
- A new species in the Daphnia curvirostris (Crustacea: Cladocera) complex from the eastern Palearctic with molecular phylogenetic evidence for the independent origin of neckteeth" (PDF). (wikipedia.org)
- Identifies two kinds of eggs: those that hatch directly into female daphnia and resistant eggs that carry the species through periods of freezing and drying. (dcmp.org)
- In order to understand potential functions of these species, we combined 16S rRNA sequencing and shotgun metagenomics to characterize the whole-organism microbiota of Daphnia magna . (nature.com)
- Daphnia species are used as a model system in ecology, ecotoxicology, and host-parasite dynamics due to their well-documented life cycle and rapid asexual reproduction 6 . (nature.com)
- The genomic content of Daphnia -associated bacteria is largely unknown due to the amplicon sequencing methods used in prior research, and we cannot make statements about the metabolic potential of these bacteria due to the relative scarcity of full genomes for close relative species. (nature.com)
- However, the functions underlying the beneficial Limnohabitans - Daphnia association are unknown, and how other species in the Daphnia microbiota contribute to host life history and what functions these species may be providing is entirely unclear. (nature.com)
- Here, we use shotgun metagenomics to characterize the bacterial species present in the Daphnia magna microbiota. (nature.com)
- In this chapter, I give a brief introduction to some endoparasite species of Daphnia . (nih.gov)
- Parasites of D. magna are predominant because parasites of this well-investigated and largest European Daphnia species are best known. (nih.gov)
- Despite this bias in representation, however, the species introduced in this chapter give a good impression of the diversity of parasites known to infect the genus Daphnia . (nih.gov)
- Six species of bacteria have been described parasitizing Daphnia . (nih.gov)
- These infections can be seen throughout the body and have been found in many Daphnia species. (nih.gov)
- The test species is Daphnia magna Straus. (scribd.com)
- We describe structural, expression, and evolutionary aspects of a Dscam homolog in 2 species of the crustacean Daphnia. (nih.gov)
- Our analysis shows that the variable exons diverged before the split of the 2 Daphnia species and is in agreement with the nearest-neighbor model for the evolution of the alternative exons. (nih.gov)
- The goal of this thesis was to develop such tools for freshwater crustaceans - Daphnia longispina species complex and its parasites. (uni-muenchen.de)
- Pipelines were then used for accessing genetic diversity of the two parasite microsporidian species (Berwaldia and MIC1) commonly infecting Daphnia longispina complex in Central Europe. (uni-muenchen.de)
- In a long-term data set (1981-1999) we examined the pelagic phenology of Daphnia galeata, a keystone species, the invertebrate predator Leptodora kindtii, phytoplankton and Secchi depth in relation to water temperature and the North Atlantic Oscillation index. (biomedsearch.com)
- Our data suggest that even low warming by 1.7 degrees C during a short, but critical seasonal period, resulting in the coincidence of two or more factors adversely affecting a keystone species, such as Daphnia, may induce changes in whole lake food webs and thus alter entire ecosystems. (biomedsearch.com)
- This research involves development of a cDNA microarray-based method for evaluating the effects of contamination on aquatic environments using the indicator species Daphnia magna . (epa.gov)
- From this research, it can be concluded that the structural features of the daphnia in many respects are quite similar to that of striated and cardiac muscle of other animal species, therefore daphnia could be used for educational purposes in undergraduate study. (ukessays.com)
- For example, some Daphnia species form neckteeth against predatory larvae of the dipteran genus Chaoborus . (springer.com)
- Various species of Daphnia possess diverse anti-predator responses. (springer.com)
- in several Daphnia species (Juračka et al. (springer.com)
- Although commercial kits exist to extract genomic DNA from several species, preparation of high quality DNA from Daphnia spp. (peerj.com)
- Two closely related Daphnia species can be distinguished by their electrophoretic Ldh genotype and habitat. (biomedcentral.com)
- We highlight in Fig. 1 many of the daily environmental rhythms experienced by Daphnia species, including temperature, ambient light, and risk of exposure to pathogens and parasites. (biomedcentral.com)
- Data on the population dynamics of five Daphnia species, viz. (brillonline.com)
- The oscillation period depends on, among other things, the Daphnia species, and increases with its size. (brillonline.com)
- Sometimes the same feeding regime leads to an equal or greater population size for a larger Daphnia species. (brillonline.com)
- This suggests that the chosen food species was not equally suitable for the two Daphnia species. (brillonline.com)
- Impact of carbon nanotubes on the toxicity of inorganic arsenic [AS(III) and AS(V)] to Daphnia magna: The role of certain arsenic species. (semanticscholar.org)
- Daphnia species are filter feeders with a relatively restricted capacity for selecting the food particles they ingest except based on their size ( DeMott, 1988 ). (biologists.org)
- Daphnia species reproduce by cyclic parthenogenesis involving both sexual and asexual reproduction. (biomedcentral.com)
- Species of Daphnia typically reproduce by cyclical parthenogenesis. (biomedcentral.com)
- The two species used in this experiment are Daphnia magna and Paramecium caudatum. (studymode.com)
- Daphnia, a genus of small planktonic crustaceans, are 0.2-5 millimetres (0.01-0.20 in) in length. (wikipedia.org)
- Daphnia are members of the order Cladocera, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory (Wiktionary) swimming style resembles the movements of fleas. (wikipedia.org)
- Daphnia magna are small invertebrate crustaceans, the size of the tip of a needle. (amnh.org)
- Daphnia are small, planktonic crustaceans. (dcmp.org)
- Daphnia (water fleas) are grouped as crustaceans under the arthropod group of Kingdom Anamalia. (educationindex.com)
- In Daphnia, we detected exon usage variability in both the brain and hemocytes (the effector cells of immunity), suggesting that Dscam plays a role in the nervous and immune systems of crustaceans, as it does in insects. (nih.gov)
- Daphnia magna (common name "water fleas") are tiny freshwater crustaceans. (sciencebuddies.org)
- As the production of nanoparticles of ZnO, TiO2 and CuO is increasing, their (eco)toxicity to bacteria Vibrio fischeri and crustaceans Daphnia magna and Thamnocephalus platyurus was studied with a special emphasis on product formulations (nano or bulk oxides) and solubilization of particles. (unboundmedicine.com)
- 474. Bianchini, A. and Wood, C.M. (2008) Sodium uptake in different life stages of crustaceans: The water flea Daphnia magna Strauss. (ubc.ca)
- Daphnia are members of the order Cladocera, and are one of the several small aquatic crustaceans commonly called water fleas because of their jumping style (although fleas are insects and thus only very distantly related). (theaquariumwiki.com)
- Also, like most crustaceans Daphnia live in an aquatic environment and so it could be possible that the heart of Daphnia may be adapted differently to respond to ethanol. (markedbyteachers.com)
- Daphnia are planktonic crustaceans that belong to the Phyllopoda (sometimes called Branchiopoda), which are characterized by flattened leaf-like legs. (studymode.com)
- The keystone zooplankton Daphnia magna has recently been used as a model system for understanding host-microbiota interactions. (nature.com)
- The zooplankton Daphnia magna provides a useful model for studying functional relationships between microbes and their hosts. (nature.com)
- The water flea Daphnia magna straus is the most commonly used zooplankton in toxicological tests. (environmental-expert.com)
- Here, we map resource-trait-epidemic connections to explain variation in fungal outbreaks (Metschnikowia bicuspidata) in a zooplankton host (Daphnia dentifera) among lakes. (sigmaaldrich.com)
- Zooplankton such as Daphnia spp. (biologists.org)
- Two major biological stressors of freshwater zooplankton of the genus Daphnia are predation and fluctuations in food quality. (pubmedcentralcanada.ca)
- One of the best-studied zooplankton taxa, the freshwater crustacean Daphnia, has a 24 h diel vertical migration (DVM) behavior whereby the organism travels up and down through the water column daily. (biomedcentral.com)
- Daphnia magna is used widely as a standard ecotoxicological indicator organism, and protocols exist for its use in assessing the toxicity of substances under acute and chronic experimental conditions. (springer.com)
- Daphnia magna as a test animal in acute and chronic toxicity tests. (springer.com)
- R. J. Bernot, M. A. Brueseke, M. A. Evans-White, and G. A. Lamberti, "Acute and chronic toxicity of imidazolium-based ionic liquids on Daphnia magna ," Environmental Toxicology and Chemistry , vol. 24, no. 1, pp. 87-92, 2005. (hindawi.com)
- C2: Acute Toxicity for Daphnia. (hindawi.com)
- Cuhra, M., Traavik, T. and Bøhn, T. (2013) Clone- and Age-Dependent Toxicity of a Glyphosate Commercial Formulation and Its Active Ingredient in Daphnia magna. (scirp.org)
- Therefore, in the present study the toxicity of a wide range of HFFRs to the water flea Daphnia magna was investigated. (uva.nl)
- Results of acute toxicity test performed with Daphnia magna should be available to select an appropriate concentration rate for the reproduction test. (scribd.com)
- The acute toxicity tests were determined using Daphnia magna. (environmental-expert.com)
- Letícia Flohr, Armando Borges de Castilhos Júnior, and William Gerson Matias, "Acute and Chronic Toxicity of Soluble Fractions of Industrial Solid Wastes on Daphnia magna and Vibrio fischeri ," The Scientific World Journal , vol. 2012, Article ID 643904, 10 pages, 2012. (hindawi.com)
- a commonly used macrolide antibiotic) are pharmaceutical compounds whose chronic toxicity to Daphnia magna had not been characterized. (usgs.gov)
- The objectives of this study were to evaluate the sensitivity of two bacterial tests commonly used in metal toxicity screening - the Vibrio fischeri bioluminescence inhibition test and the Pseudomonas putida growth inhibition test - in comparison to the standard acute Daphnia magna test, and to estimate applicability of the selected methods to the toxicity testing of environmental samples. (semanticscholar.org)
- Daphnia manga (D. magna) is an ideal candidate in fresh water toxicity testing. (bham.ac.uk)
- This study investigates acute toxicity, oxidative damage, and antioxidant enzyme parameters in neonate and adult Daphnia magna exposed to DBP. (peerj.com)
- In the present study, we conducted the evaluation of acute toxicity on Daphnia magna that commonly used as a model organism in ecotoxicological studies for non-target organism evaluation. (koreascience.or.kr)
- values showed no difference between OsCK1 rice (3,147.18 mg/L) and non-GM rice (3,596.27 mg/L). CONCLUSION: This result suggested that there was no significant difference in toxicity to Daphnia magna between OsCK1 rice and non-GM counterpart. (koreascience.or.kr)
- International Organisation for Standardisation, 1982, Water Quality Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea), ISO 6341/1982, Geneva, Swittzerland. (hindawi.com)
- A search on the Internet using the term ' Daphnia ' or 'Cladocera' will also bring up a large body of information. (studymode.com)
- Daphnia are small water fleas (a type of crustacean) which are less than 3mm (on average). (cyberessays.com)
- Daphnia, otherwise known as water fleas, have a circulatory system similar to mammals. (education.com)
- In this project, water fleas ( Daphnia magna ), a semi-transparent freshwater crustacean, are used to study the effects of caffeine on heart rate. (sciencebuddies.org)
- In the present study, the population dynamics and host-genotype specificity of the ichthyosporean Caullerya mesnili, a common endoparasite of Daphnia water fleas, were analysed based on the observed sequence variation in the first internal transcribed spacer (ITS1) of the ribosomal DNA. (salford.ac.uk)
- Resources, key traits and the size of fungal epidemics in Daphnia populations. (sigmaaldrich.com)
- Epidemics grew larger in more dense Daphnia populations, but host density was unrelated to host fecundity (thus breaking its link to resources). (sigmaaldrich.com)
- Significant differences in the clonal composition between random and infected subsamples of Daphnia populations were detected on six of seven tested occasions, confirming genetic specificity of the host-parasite interaction in this system. (deepdyve.com)
- Here, we traced genetic variation (based on sequence variants in the internal transcribed spacer region, ITS) among seven geographically isolated populations of the ichthyosporean Caullerya mesnili , a common microparasite of the cladoceran Daphnia (here, the D. longispina hybrid complex). (biomedcentral.com)
- Selfing and life-table experiments were performed for two such Daphnia populations. (biomedcentral.com)
- Daphnia is also a popular food organism for Hydra and other invertebrates. (flinnsci.com)
- Daphnia is also popular as a food organism for Hydra and other invertebrates. (flinnsci.com)
- Daphnia feeds unselectively on phytoplankton and thus links higher trophic levels to primary production, being preyed upon by both vertebrates like fish and a variety of invertebrates (e.g. (biologists.org)
- Daphnia are invertebrates and also have an exoskeleton, jointed appendages, a dorsal heart and open blood system. (markedbyteachers.com)
- This is because Daphnia differ to humans in many ways firstly Daphnia are invertebrates whereas humans are vertebrates. (markedbyteachers.com)
- The article, Biotreatment of wastewater using aquatic invertebrates, Daphnia magna and Paramecium caudatum, mainly pertains to the idea of cleaning dirty, polluted water. (studymode.com)
- Daphnia are typically filter feeders, ingesting mainly unicellular algae and various sorts of organic detritus including protists and bacteria Beating of the legs produces a constant current through the carapace which brings such material into the digestive tract. (wikipedia.org)
- The daphnias eat all kinds of algae and vegetation. (cyberessays.com)
- Daphnia, like many algae eating microinverts, will swim towards a light source. (plantedtank.net)
- When lupins and ragworts are present in large densities in fields, there is a concern that alkaloids may leach into freshwater environments in amounts that may affect non-target organisms, such as Daphnia magna . (springer.com)
- Daphnia are key model organisms for mechanistic studies of phenotypic plasticity, adaptation and microevolution, which have led to an increasing demand for genomics resources. (peerj.com)
- Daphnia are the organisms that are involved in this experiment to find out what effect alcohol has on their heartbeat. (markedbyteachers.com)
- Before the lab a handout with information on daphnia should be read to familiarize oneself with the little organisms. (cram.com)
- Daphnia magna are most commonly used in aquariums because they are heavy filter feeders and usually eat many organisms that are of appropriate size while Paramecium caudatum are usually found in water containing bacteria or decaying organic, however both thrive in it. (studymode.com)
- In this study, long-term multigenerational effects on Daphnia magna were assessed using various exposure times (3, 7, 14, and 21 days) in three generations (F0, F1 and F2). (americanelements.com)
- Using a natural host-parasite system with a well-established pattern of genetic specificity, the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa, we found that only hosts from susceptible host-parasite genetic combinations mounted a cellular response following exposure to the parasite. (stir.ac.uk)
- We evaluated seven candidate reference genes for QPCR in Daphnia magna after exposure to kairomones. (pubmedcentralcanada.ca)
- We evaluated the same set of candidate reference genes for QPCR in Daphnia magna after exposure to a microcystin-producing and a microcystin-free strain of the cyanobacterium Microcystis aeruginosa . (pubmedcentralcanada.ca)
- These results provide a functional link for lipid peroxidation, antioxidant capacity, and antioxidant enzyme levels in the Daphnia magna response to DBP exposure. (peerj.com)
- The reader familiar with Daphnia may skip this chapter and move on to Chapter 3. (studymode.com)
Crustacean Daphnia magna2
- A European crustacean (Daphnia magna) - bacterium (Pasteuria ramosa) system typifies such specificity and high virulence. (stir.ac.uk)
- The goal of this project is to test whether caffeine has an effect on heart rate, using the freshwater crustacean, Daphnia magna , as an experimental model system. (sciencebuddies.org)
- Place one daphnia onto a cavity slide and place under microscope. (educationindex.com)
- Take the daphnia from under the microscope and add some 0.1% caffeine solution to it. (educationindex.com)
- Place back under the microscope and allow the daphnia to adjust again. (educationindex.com)
- Daphnia , the "water-flea," has long been popular for simple physiology studies because its heartbeat is easily viewed under the microscope. (flinnsci.com)
- Daphnia has long been popular for simple physiology studies because its heartbeat is easily viewed under the microscope. (flinnsci.com)
- Materials included: 72 microscope slides, 20 petri dishes, 1 tube petroleum jelly, 30 disposable pipets, 1 Daphnia magna culture. (boreal.com)
- You will need a microscope for observing Daphnia closely enough to monitor heart rate. (sciencebuddies.org)
- This allows you to monitor the heart rate of individual Daphnia that you observe with a microscope. (sciencebuddies.org)
- You can use a dissecting microscope, placing the individual Daphnia in a small drop of water so that it cannot swim out of your field of view. (sciencebuddies.org)
- This impression (All Parts Of A Microscope Luxury Daphnia Page 2) earlier mentioned is actually branded along with:posted through Albert Banks with 2018-09-29 18:46:18. (chaussurenikesolde.com)
- The assessment of a clonal gradient of Daphnia in the presence and absence of infochemicals provides a promising approach to identify further genes involved in the induction of morphological defences by correlating gene expression and morphology. (biologists.org)
- This information is obtained by constructing phylogenetic trees of candidate genes with the knowledge that the Daphnia genome is composed of many expanded gene families. (pubmedcentralcanada.ca)
- However, there is little information at the transcriptional level linking the expression patterns of genes to the rhythmic physiology/behavior of Daphnia . (biomedcentral.com)
- In my previous research, the effects of different water conditions (i.e. seasons and runoff) on Daphnia magna were examined. (amnh.org)
- The Daphnia arrived soon after I collected the water. (amnh.org)
- Hi Ray, This is practically all I did as a graduate student (I guess I must have done something else to get my degreebut it didn't feel like it).You can raise daphnia in the water where you find them but this probably would not be ideal for aquarium use. (thekrib.com)
- If you live anywhere where there is fish-free, standing water there is a good chance you can find Daphnia or at least ephipia. (thekrib.com)
- the beaker of water and daphnias need to be kept on the bench away from the edge to make sure it does not get knocked off. (cyberessays.com)
- If knocked off the daphnias will die and the water is a hazard for others. (cyberessays.com)
- The beaker of water and daphnia could spill onto the wire and electrocute someone or blow the electrics. (cyberessays.com)
- Daphnia also eat yeast from suspension-prepare by adding a pinch of active dry yeast to 100 mL of warm water and let stand 2-3 hours. (flinnsci.com)
- After you receive your Daphnia, either in the mail or from the store, put them in a clean glass jar and add distilled room temperature water until full. (education.com)
- Add JUST A TINY PINCH of yeast- too much will foul the water and kill the Daphnia. (education.com)
- This study examined the interactions between Daphnia magna and a water-soluble, lysophophatidylcholine coated single-walled carbon nanotube. (biomedsearch.com)
- has captured water flea (Daphnia sp. (sciencephoto.com)
- Photomicrograph of Daphnia , the common water flea. (sciencebuddies.org)
- In both cases, you want to make your measurements quickly, so that the Daphnia does not become stressed in the small volume of water. (sciencebuddies.org)
- The water flea Daphnia satisfies these criteria, and genomic approaches capitalizing on the pivotal role Daphnia plays in the functioning of pelagic freshwater food webs will enable investigations of eco-evolutionary dynamics in unprecedented detail. (royalsocietypublishing.org)
- Just supply a few litres of old tank water ( Daphnia Magna 18-20°C (64.4-68°F) , Daphnia moina 20-28°C (68-82.4°F) with a pH of 7.5-9 (add 1 tsp of Bicarbonate of soda per 2 litres) and place in it an air line to ensure it is aerated. (theaquariumwiki.com)
- The airstone is required to move the water and food particles around in the mid-column, so the daphnia can find them. (theaquariumwiki.com)
- If you are growing green water to feed daphnia, temperature is critical. (theaquariumwiki.com)
- Use a turkey baster to feed the daphnia tank green water several times per day. (theaquariumwiki.com)
- Chronobiology research in Daphnia has focused primarily on behavioral processes like locomotor activity, daily vertical migration (DVM) through a water column, and mandibular activity ('feeding') [ 20 - 22 ]. (biomedcentral.com)
- In the lab the stream is getting pumped with salty potassium filled water that can kill daphnia, habitants of the stream, if the concentration gets too high. (cram.com)
- The Daphnia were reared by mixing a solution containing dried sheep manure, garden soil, and 1 liter of pond water. (studymode.com)
- A large culture of daphnia can clear a pond of green water almost overnight, so feeding them green water over an extended period of time is not practical. (tropical-fish-keeping.com)
- Here, we show in mutation-accumulation lines of asexual Daphnia that the rate of loss of nucleotide heterozygosity by ameiotic recombination is substantially greater than the rate of introduction of new variation by mutation. (pnas.org)
- During the asexual phase female Daphnia produce genetically identical offspring [ 6 ]. (biomedcentral.com)
- Here, we highlight the combination of traits and ecological interactions that make Daphnia a definitive model system, focusing on the additional power and capabilities enabled by recent molecular and genomic advances. (royalsocietypublishing.org)
- Antibiotic-induced disturbance of the microbiota had a strong effect on the subsequent colonization of Daphnia by affecting ecological interactions between members of the microbiota. (biomedcentral.com)
- Daphnia has long been a model for ecological investigation largely because of its cosmopolitan distribution and central role in the trophic cascades of freshwater ecosystems [ 17 ]. (biomedcentral.com)
Growth and fecundity3
- 2. As cyanobacteria feature a deficiency in some essential lipids that leads to a decline in the growth and fecundity of Daphnia, an important freshwater herbivore, we investigated Daphnia magna s Strauss allocation of lipids such as polyunsaturated fatty acids (PUFAs) and cholesterol during an experimental non-toxic cyanobacterial bloom. (uni-konstanz.de)
- Nutrition bioassays in which polyunsaturated fatty acids (PUFA)-deficient diets were supplemented with free long-chain PUFA (≥C20) consistently revealed positive effects on somatic growth and fecundity of Daphnia. (uni-konstanz.de)
- Here, we evaluate the potential of free and phospholipid-bound dietary eicosapentaenoic acid (EPA) to support somatic growth and fecundity of Daphnia magna. (uni-konstanz.de)
- Phylogenetic analysis shows a high degree of amino acid conservation between Daphnia and insects except in the alternative exons, which diverge greatly between these taxa. (nih.gov)
- This variation in food quality should lead to fluctuating imbalances and elemental constraints on organismal performance and life-histories particularly for high-phosphorus (P) taxa such as Daphnia . (frontiersin.org)
- Verification of the method was done by comparing the dataset with the previous study of population structure of Daphnia parasite Caullerya mesnili based on cloning and Sanger sequencing. (uni-muenchen.de)
- We tested this hypothesis exploring field data of the Daphnia-Caullerya host-parasite system. (deepdyve.com)
- Since only a few drugs have been tested on the daphnia heart, it seemed useful to test other drugs to see whether the responses of the daphnia heart correlated with the responses of the drugs to the human heart. (ukessays.com)
- Evaluation and assessment of biosafety for Bt-transgenic rice : Responses of Daphnia magna fed on Bt-transgenic rice variety, J. Appl. (koreascience.or.kr)
- Daphnia eggs for sale are generally enclosed in ephippia (a thick shell, consisting of two chitinous plates, that encloses and protects the winter eggs of a cladoceran). (wikipedia.org)
- Hence, we established a technique to inject exogenous materials into ovulated eggs and developed a dsRNA-based RNAi method for Daphnia magna. (nih.gov)
- Lipids are key components of cell membranes, the main energy storage form in Daphnia , and are heavily invested in eggs ( Arts, 1999 ). (biologists.org)
- The female Daphnia produce haploid eggs which are fertilized by the male during mating to form diapausing resting eggs contained in an ephippium. (biomedcentral.com)
- Shedding of un-hatched eggs, presence of male Daphnia, ephippial eggs and differences in the size of adults at the end of the test are also recorded. (chemex.co.uk)
- Das Ziel der vorliegenden Arbeit war die Entwicklung solcher Werkzeuge für den Daphnia longispina-Artenkomplex (Süßwasser-Crustaceen) und seine Parasiten. (uni-muenchen.de)
- An individual Daphnia life-span depends on factors such as temperature and the abundance of predators, but can be 13-14 months in some cold, oligotrophic fish-free lakes. (wikipedia.org)
- Consumptive mortality increased at higher rates with a rise in temperature than net recruitment, resulting in lower Daphnia densities at the end of the CWS. (biomedsearch.com)
- Complementary roles of photoperiod and temperature in environmental sex determination in Daphnia spp. (biologists.org)
- WARD'S How Does Temperature Affect Daphnia Heart Rate? (boreal.com)
- I feed them 1-2 times a week with large amounts of mosquito larvae and daphnia (swish the net through the mosquito/daphnia culture, dump everything into the Lucania container). (thekrib.com)
- mosquito larvae, bloodworms plus daphnia. (novawavesoftware.com)
- daphnia, tubifex worms else mosquito larvae on a pet store. (novawavesoftware.com)
- snails daphnia, mosquito larvae, midge fly larvae plus blackworms. (novawavesoftware.com)
- However, only a weak signal of host-genotype specificity between C. mesnili and Daphnia genotypes was detected. (salford.ac.uk)
- I started research in my seventh-grade year on how different fertilizers would affect the Daphnia magna and how different pond waters affect them. (amnh.org)
- This was to see how the two different pond waters affected the Daphnia . (amnh.org)
- It is said that keeping pond snails in with your daphnia can help produce food for daphnia from the snail's own waste. (theaquariumwiki.com)
- daphnia) as of your pet shop before catching them as of a pond. (novawavesoftware.com)
- Maintain Daphnia in indirect light at 18 to 24 ºC. (flinnsci.com)
- Young female Daphnia, aged up to 24 hours are exposed to the test sample at a range of concentrations during 21 days. (scribd.com)
- Ideally, your experiment will span the entire range of concentrations that produce a response (i.e., change in Daphnia heart rate). (sciencebuddies.org)
- To investigate this hypothesis, the host-associated microbiota of the invertebrate eco(toxico)logical model Daphnia was experimentally disturbed using different concentrations of the antibiotic oxytetracycline. (biomedcentral.com)
- The Daphnia population of lake Greifensee (Switzerland) was sampled and subjected to parasite screening and host genotyping during C. mesnili epidemics of four consecutive years. (salford.ac.uk)
- The ITS1 of wild-caught C. mesnili-infected Daphnia was sequenced using the 454 pyrosequencing platform. (salford.ac.uk)
- Interestingly, male Daphnia are dominated with epigenetic modifications that globally promote elevated gene expression, while female Daphnia are dominated with epigenetic modifications that reduce gene expression globally. (biomedcentral.com)
- For examples, CpG methylation (positively correlated with gene expression level) is significantly higher in almost all differentially methylated sites in male compared to female Daphnia . (biomedcentral.com)
- Daphnia live in various aquatic environments ranging from acidic swamps to freshwater lakes, ponds, streams and rivers. (wikipedia.org)
- Daphnia live in various aquatic environments ranging from acidic swamps to freshwater lakes and ponds. (wikipedia.org)
- Due to its intermediate size, Daphnia utilizes both diffusion and circulatory methods, producing hemoglobin in low-oxygen environments. (wikipedia.org)
- Because its ecology is profoundly influenced by both genetic polymorphism and phenotypic plasticity, Daphnia represents a model system with tremendous potential for developing a mechanistic understanding of the relationship between traits at the genetic, organismal and population levels, and consequences for community and ecosystem dynamics. (royalsocietypublishing.org)
- Very important invertebrate predators of Daphnia are aquatic larvae of the phantom midge Chaoborus spp. (biologists.org)